WorldWideScience

Sample records for forage based animal

  1. Forage based animal production systems and sustainability, an invited keynote

    Directory of Open Access Journals (Sweden)

    Abdul Shakoor Chaudhry

    2008-07-01

    Full Text Available Forages are essential for the successful operation of animal production systems. This is more relevant to ruminants which are heavily dependant upon forages for their health and production in a cost-effective and sustainable manner. While forages are an economical source of nutrients for animal production, they also help conserve the soil integrity, water supply and air quality. Although the role of these forages for animal production could vary depending upon the regional preferences for the animal and forage species, climate and resources, their importance in the success of ruminant production is acknowledged. However with the increasing global human population and urbanisation, the sustainability of forage based animal production systems is sometimes questioned due to the interrelationship between animal production and the environment. It is therefore vital to examine the suitability of these systems for their place in the future to supply quality food which is safe for human consumption and available at a competitive price to the growing human population. Grassland and forage crops are recognised for their contribution to the environment, recreation and efficiency of meat and milk production,. To maintain sustainability, it is crucial that such farming systems remain profitable and environmentally friendly while producing nutritious foods of high economical value. Thus, it is pertinent to improve the nutritive value of grasses and other forage plants in order to enhance animal production to obtain quality food. It is also vital to develop new forages which are efficiently utilised and wasted less by involving efficient animals. A combination of forage legumes, fresh or conserved grasses, crop residues and other feeds could help develop an animal production system which is economically efficient, beneficial and viable. Also, it is crucial to use efficient animals, improved forage conservation methods, better manure handling, and minimum

  2. Linking animal population dynamics to alterations in foraging behaviour

    DEFF Research Database (Denmark)

    Nabe-Nielsen, Jacob; Sibly, Richard; Tougaard, Jakob

    the animals’ ability to forage efficiently and to sustain their energy intake, is influenced by noise emitted from wind turbines and ships. The energy levels in turn affect their survival. The fine-scale movements of the simulated animals was governed by a spatial memory, which allowed the model to produce......Background/Question/Methods The survival of animal populations is strongly influenced by the individuals’ ability to forage efficiently, yet there are few studies of how populations respond when disturbances cause animals to deviate from their natural foraging behavior. Animals that respond...... that are increasingly exposed to noise from ships, wind turbines, etc. In the present study we investigate how the dynamics of the harbor porpoise population (Phocoena phocoena) in the inner Danish waters is influenced by disturbances using an agent- based simulation model. In the model animal movement, and hence...

  3. A theoretical analysis of foraging efficiency of grazing animals | RI ...

    African Journals Online (AJOL)

    A mathematical model of the change in quantity of forage during grazing is constructed, assuming (1) that forage requirement by grazing animals is constant, and (2) that intake is equal to requirement when forage is in free supply but (3) that below a certain supply level intake becomes restricted and is proportional to supply ...

  4. Flexible search tactics and efficient foraging in saltatory searching animals.

    Science.gov (United States)

    John O'Brien, W; Evans, B I; Browman, H I

    1989-03-01

    Foraging is one of the most important endeavors undertaken by animals, and it has been studied intensively from both mechanistic-empirical and optimal foraging perspectives. Planktivorous fish make excellent study organisms for foraging studies because they feed frequently and in a relatively simple environment. Most optimal foraging studies of planktivorous fish have focused, either on diet choice or habitat selection and have assumed that these animals used a cruise search foraging strategy. We have recently recognized that white crappie do not use a cruise search strategy (swimming continuously and searching constantly) while foraging on zooplankton but move in a stop and go pattern, searching only while paused. We have termed thissaltatory search. Many other animals move in a stop and go pattern while foraging, but none have been shown to search only while paused. Not only do white crappie search in a saltatory manner but the components of the search cycle change when feeding on prey of different size. When feeding on large prey these fish move further and faster after an unsuccessful search than when feeding on small prey. The fish also pause for a shorter period to search when feeding on large prey. To evaluate the efficiency of these alterations in the search cycle, a net energy gain simulation model was developed. The model computes the likelihood of locating 1 or 2 different size classes of zooplankton prey as a function of the volume of water scanned. The volume of new water searched is dependent upon the dimensions of the search volume and the length of the run. Energy costs for each component of the search cycle, and energy gained from the different sized prey, were assessed. The model predicts that short runs produce maximum net energy gains when crappie feed on small prey but predicts net energy gains will be maximized with longer runs when crappie feed on large prey or a mixed assemblage of large and small prey. There is an optimal run length due to

  5. Utilization of 15N in the sequence of mineral fertilizer - forage - animal - slurry - forage

    International Nuclear Information System (INIS)

    Peschke, H.

    1981-01-01

    After systematic application of 15 N-ammonium nitrate, the change of the dinuclidic composition and 15 N quantity was studied by isotope analysis of several open systems in the sequence mineral fertilizer - (soil) - forage - (animal) - slurry - (soil) - forage. The relative 15 N isotope frequency of 50 atom% in the mineral fertilizer declined to 12.2 to 21.4 atom% in the forage (beet, oats, hay) and went down to 3.15 atom% in the slurry of a dairy cow fed on this forage. Silage maize manured with the slurry of the dairy cow only showed 1.98 atom %, green oats grown after the silage maize on the same area was found to have 0.45 atom%. The 15 N quantity of 104.5 g N in the fertilizer gradually decreased to 41.6 g N in the forage, 30.5 g N in the slurry and 22.6 g N in the silage maize. The causes discussed are 15 N isotope dilution as qualitative factor and productive and unproductive N losses as quantitative factors. (author)

  6. Evaluation of wild animals browsing preferences in forage resources

    Directory of Open Access Journals (Sweden)

    Giovanni Argenti

    2017-09-01

    Full Text Available Excessive presence of wild ungulates can produce negative effects on herbaceous crops or woody species, and to face this problem, habitat improvements are often performed to recreate suitable environments for a given animal species and to attract animals far from cultivated crops. A common example of these interventions is represented by grassland restoration and to evaluate the real animal preferences on restored forage resources a proper trial was established in a hilly area of Tuscany (central Italy, inside the historical Park of Pratolino, near Florence. The trial compared six different forage species or mixtures sown in plots: vegetal material was represented by two pure stands (Onobrychis viciifolia and Medicago sativa and four mixtures differing in number and kind of used species. Plots were utilised only by wild animals occurring in the area. Data collection consisted of botanical samples in each plot in different periods to obtain the percent presence of each species. At the same time, a visual estimation of animal intake on all occurring species was performed to obtain the browsing ratio of single species and overall defoliation rate for each species/mixture. Moreover, six camera traps were placed on the boundary of the experimental site to record videos of wild animals browsing in the area for identification of animals actually occurring on different plots and for comparison of these results with botanical data. Vegetation surveys permitted a proper evaluation of animals intake and of their feeding preferences. In general, sown species performed a major role in animal browsing, even if in some periods also a few native species (such as Plantago lanceolata or Cichorium intybus were utilised in a strong way, depending on vegetation context and existing biomass. Camera traps results permitted the identification of browsing animal species (mainly represented by roe deer and plots frequentation resulted to be highly related to animal

  7. Determination of water in forages and animal feeds by Karl Fischer titration.

    Science.gov (United States)

    Van Erem, T; Thiex, N; Pohmer, J; Poffenbarger, W M; Smith, V; Patel, E

    1998-01-01

    Oven methods for determining moisture (volatiles) in forages and other animal feeds are empirical. The moisture concentration obtained depends upon the time and temperature the sample was dried and is influenced by the presence of other volatiles than water. A validated reference method to measure water in forages and animal feeds could be used to evaluate the appropriateness of oven methods for various types of animal feeds and forages. Karl Fischer titration is a well-established method for determining water. However, thorough extraction of water from forages and feeds is a challenge because they often contain cellular structures that release water slowly. Water was successfully extracted into methanol-formamide (50 + 50) by high-speed homogenization and then titrated directly at 50 degrees C with a one-component Karl Fischer reagent based on imidazole. The method is described in detail, results of day-to-day repeatability and laboratory-to-laboratory reproducibility are reported, and preliminary comparison data between oven methods are provided.

  8. Recycling biosolids and lake-dredged materials to pasture-based animal agriculture: Alternative nutrient sources for forage productivity and sustainability

    Science.gov (United States)

    Domestic sewage sludge or biosolids and lake-dredged materials are examples of materials that can be used to cut fertilizer costs in pasture-based animal agriculture. Sustainable biosolids and lake-dredged materials management is based upon controlling and influencing the quantity, quality and chara...

  9. Kudu foraging behaviour: influenced by animal density? | van der ...

    African Journals Online (AJOL)

    The dry season utilisation patterns of two woody species, Acacia tortilis and Boscia albitrunca, in two comparable sites but subjected to different kudu densities, were studied to determine if kudu adapt their feeding behaviour in response to animal density. Shoots of plants in the high-density area were vertically more ...

  10. Variations among animals when estimating the undegradable fraction of fiber in forage samples

    Directory of Open Access Journals (Sweden)

    Cláudia Batista Sampaio

    2014-10-01

    Full Text Available The objective of this study was to assess the variability among animals regarding the critical time to estimate the undegradable fraction of fiber (ct using an in situ incubation procedure. Five rumenfistulated Nellore steers were used to estimate the degradation profile of fiber. Animals were fed a standard diet with an 80:20 forage:concentrate ratio. Sugarcane, signal grass hay, corn silage and fresh elephant grass samples were assessed. Samples were put in F57 Ankom® bags and were incubated in the rumens of the animals for 0, 6, 12, 18, 24, 48, 72, 96, 120, 144, 168, 192, 216, 240 and 312 hours. The degradation profiles were interpreted using a mixed non-linear model in which a random effect was associated with the degradation rate. For sugarcane, signal grass hay and corn silage, there were no significant variations among animals regarding the fractional degradation rate of neutral and acid detergent fiber; consequently, the ct required to estimate the undegradable fiber fraction did not vary among animals for those forages. However, a significant variability among animals was found for the fresh elephant grass. The results seem to suggest that the variability among animals regarding the degradation rate of fibrous components can be significant.

  11. self-limiting complete feed changes forage intake and animal ...

    African Journals Online (AJOL)

    Rangeland or hay-based finishing systems often do not allow kids to reach slaughter weights of 30 - 50 kg by 12 months. This study determined the effects of a complete feed (CF) and a self-limiting complete feed (LCF) alone or in combination with ad libitum access to sorghum-sudan hay (SS) on average daily gain (ADG) ...

  12. Dive characteristics can predict foraging success in Australian fur seals (Arctocephalus pusillus doriferus as validated by animal-borne video

    Directory of Open Access Journals (Sweden)

    Beth L. Volpov

    2016-03-01

    Full Text Available Dive characteristics and dive shape are often used to infer foraging success in pinnipeds. However, these inferences have not been directly validated in the field with video, and it remains unclear if this method can be applied to benthic foraging animals. This study assessed the ability of dive characteristics from time-depth recorders (TDR to predict attempted prey capture events (APC that were directly observed on animal-borne video in Australian fur seals (Arctocephalus pusillus doriferus, n=11. The most parsimonious model predicting the probability of a dive with ≥1 APC on video included only descent rate as a predictor variable. The majority (94% of the 389 total APC were successful, and the majority of the dives (68% contained at least one successful APC. The best model predicting these successful dives included descent rate as a predictor. Comparisons of the TDR model predictions to video yielded a maximum accuracy of 77.5% in classifying dives as either APC or non-APC or 77.1% in classifying dives as successful verses unsuccessful. Foraging intensity, measured as either total APC per dive or total successful APC per dive, was best predicted by bottom duration and ascent rate. The accuracy in predicting total APC per dive varied based on the number of APC per dive with maximum accuracy occurring at 1 APC for both total (54% and only successful APC (52%. Results from this study linking verified foraging dives to dive characteristics potentially opens the door to decades of historical TDR datasets across several otariid species.

  13. Animation-based Sketching

    DEFF Research Database (Denmark)

    Vistisen, Peter

    of contributions. In the produced work, I expand upon animation as a sketching approach to communicate, and explore interaction and user experience design concepts that are hard to grasp via traditional means of sketching. I propose that the sequential, temporal, material and narrative qualities of animation may...... experiments has been carried out, applying animation-based sketching in various contexts and at varying points in the design process. In the studies, I evaluate the viability of the approach, the practical integration into the design process, and map how consensus between stakeholders in design can...... be established through animation -based sketches. Thus, the scope of this project is practice-inclined, towards qualifying animation as an approach for design sketching in practice....

  14. Quantifying animal movement for caching foragers: the path identification index (PII) and cougars, Puma concolor

    Science.gov (United States)

    Ironside, Kirsten E.; Mattson, David J.; Theimer, Tad; Jansen, Brian; Holton, Brandon; Arundel, Terry; Peters, Michael; Sexton, Joseph O.; Edwards, Thomas C.

    2017-01-01

    Relocation studies of animal movement have focused on directed versus area restricted movement, which rely on correlations between step-length and turn angles, along with a degree of stationarity through time to define behavioral states. Although these approaches may work well for grazing foraging strategies in a patchy landscape, species that do not spend a significant amount of time searching out and gathering small dispersed food items, but instead feed for short periods on large, concentrated sources or cache food result in movements that maybe difficult to analyze using turning and velocity alone. We use GPS telemetry collected from a prey-caching predator, the cougar (Puma concolor), to test whether adding additional movement metrics capturing site recursion, to the more traditional velocity and turning, improve the ability to identify behaviors. We evaluated our movement index’s ability to identify behaviors using field investigations. We further tested for statistical stationarity across behaviors for use of topographic view-sheds. We found little correlation between turn angle, velocity, tortuosity, and site fidelity and combined them into a movement index used to identify movement paths (temporally autocorrelated movements) related to fast directed movements (taxis), area restricted movements (search), and prey caching (foraging). Changes in the frequency and duration of these movements were helpful for identifying seasonal activities such as migration and denning in females. Comparison of field investigations of cougar activities to behavioral classes defined using the movement index and found an overall classification accuracy of 81%. Changes in behaviors resulted in changes in how cougars used topographic view-sheds, showing statistical non-stationarity over time. The movement index shows promise for identifying behaviors in species that frequently return to specific locations such as food caches, watering holes, or dens, and highlights the role

  15. Breeding for genetic improvement of forage plants in relation to increasing animal production with reduced environmental footprint.

    Science.gov (United States)

    Kingston-Smith, A H; Marshall, A H; Moorby, J M

    2013-03-01

    Animal production is a fundamental component of the food supply chain, and with an increasing global population production levels are set to increase. Ruminant animals in particular are valuable in their ability to convert a fibre-rich forage diet into a high-quality protein product for human consumption, although this benefit is offset by inefficiencies in rumen fermentation that contribute to emission of significant quantities of methane and nitrogenous waste. Through co-operation between plant and animal sciences, we can identify how the nutritional requirements of ruminants can be satisfied by high-quality forages for the future. Selective forage plant breeding has supported crop improvement for nearly a century. Early plant breeding programmes were successful in terms of yield gains (4% to 5% per decade), with quality traits becoming increasingly important breeding targets (e.g. enhanced disease resistance and digestibility). Recently, demands for more sustainable production systems have required high yielding, high-quality forages that enable efficient animal production with minimal environmental impact. Achieving this involves considering the entire farm system and identifying opportunities for maximising nutrient use efficiency in both forage and animal components. Forage crops of the future must be able to utilise limited resources (water and nutrients) to maximise production on a limited land area and this may require us to consider alternative plant species to those currently in use. Furthermore, new breeding targets will be identified as the interactions between plants and the animals that consume them become better understood. This will ensure that available resources are targeted at delivering maximum benefits to the animal through enhanced transformation efficiency.

  16. Seasonal variation of the Cs137 contamination of the tree forage of wild hoofed animals of the Pripyat National Park

    International Nuclear Information System (INIS)

    Uglyanets, A.V.

    2011-01-01

    In the conditions of the Republic of Belarus there were presented the results of studies of the 137Cs contamination of the tree forage of wild hoofed animals in the Pripyat national park. The parameters of this radioisotope accumulation in the shoots of different trees, shrubs, dwarf shrubs and bushes were studied in the seasonal and edaphic aspects, and their influencing factors were specified. The 137Cs contamination of the tree forage of wild hoofed animals was determined to be dependent on the soil pollution degree, growth conditions and species composition of plants and their proportion in the phytocenosis, as well as on the edaphic conditions and a season of the year

  17. Soil-foraging animals alter the composition and co-occurrence of microbial communities in a desert shrubland.

    Science.gov (United States)

    Eldridge, David J; Woodhouse, Jason N; Curlevski, Nathalie J A; Hayward, Matthew; Brown, Mark V; Neilan, Brett A

    2015-12-01

    Animals that modify their physical environment by foraging in the soil can have dramatic effects on ecosystem functions and processes. We compared bacterial and fungal communities in the foraging pits created by bilbies and burrowing bettongs with undisturbed surface soils dominated by biocrusts. Bacterial communities were characterized by Actinobacteria and Alphaproteobacteria, and fungal communities by Lecanoromycetes and Archaeosporomycetes. The composition of bacterial or fungal communities was not observed to vary between loamy or sandy soils. There were no differences in richness of either bacterial or fungal operational taxonomic units (OTUs) in the soil of young or old foraging pits, or undisturbed soils. Although the bacterial assemblage did not vary among the three microsites, the composition of fungi in undisturbed soils was significantly different from that in old or young foraging pits. Network analysis indicated that a greater number of correlations between bacterial OTUs occurred in undisturbed soils and old pits, whereas a greater number of correlations between fungal OTUs occurred in undisturbed soils. Our study suggests that digging by soil-disturbing animals is likely to create successional shifts in soil microbial and fungal communities, leading to functional shifts associated with the decomposition of organic matter and the fixation of nitrogen. Given the primacy of organic matter decomposition in arid and semi-arid environments, the loss of native soil-foraging animals is likely to impair the ability of these systems to maintain key ecosystem processes such as the mineralization of nitrogen and the breakdown of organic matter, and to recover from disturbance.

  18. Data-Foraging-Oriented Reconnaissance Based on Bio-Inspired Indirect Communication for Aerial Vehicles

    Directory of Open Access Journals (Sweden)

    Josué Castañeda Cisneros

    2017-07-01

    Full Text Available In recent years, aerial vehicles have allowed exploring scenarios with harsh conditions. These can conduct reconnaissance tasks in areas that change periodically and have a high spatial and temporal resolution. The objective of a reconnaissance task is to survey an area and retrieve strategic information. The aerial vehicles, however, have inherent constraints in terms of energy and transmission range due to their mobility. Despite these constraints, the Data Foraging problem requires the aerial vehicles to exchange information about profitable data sources. In Data Foraging, establishing a single path is not viable because of dynamic conditions of the environment. Thus, reconnaissance must be focused on periodically searching profitable environmental data sources, as some animals perform foraging. In this work, a data-foraging-oriented reconnaissance algorithm based on bio-inspired indirect communication for aerial vehicles is presented. The approach establishes several paths that overlap to identify valuable data sources. Inspired by the stigmergy principle, the aerial vehicles indirectly communicate through artificial pheromones. The aerial vehicles traverse the environment using a heuristic algorithm that uses the artificial pheromones as feedback. The solution is formally defined and mathematically evaluated. In addition, we show the viability of the algorithm by simulations which have been tested through various statistical hypothesis.

  19. Costs of Foraging Predispose Animals to Obesity-Related Mortality when Food Is Constantly Abundant.

    Science.gov (United States)

    McNamara, John M; Houston, Alasdair I; Higginson, Andrew D

    2015-01-01

    Obesity is an important medical problem affecting humans and animals in the developed world, but the evolutionary origins of the behaviours that cause obesity are poorly understood. The potential role of occasional gluts of food in determining fat-storage strategies for avoiding mortality have been overlooked, even though animals experienced such conditions in the recent evolutionary past and may follow the same strategies in the modern environment. Humans, domestic, and captive animals in the developed world are exposed to a surplus of calorie-rich food, conditions characterised as 'constant-glut'. Here, we use a mathematical model to demonstrate that obesity-related mortality from poor health in a constant-glut environment should equal the average mortality rate in the 'pre-modern' environment when predation risk was more closely linked with foraging. It should therefore not be surprising that animals exposed to abundant food often over-eat to the point of ill-health. Our work suggests that individuals tend to defend a given excessive level of reserves because this level was adaptive when gluts were short-lived. The model predicts that mortality rate in constant-glut conditions can increase as the assumed health cost of being overweight decreases, meaning that any adaptation that reduced such health costs would have counter-intuitively led to an increase in mortality in the modern environment. Taken together, these results imply that efforts to reduce the incidence of obesity that are focussed on altering individual behaviour are likely to be ineffective because modern, constant-glut conditions trigger previously adaptive behavioural responses.

  20. Effects of forage type, animal characteristics and feed intake on faecal particle size in goat, sheep, llama and cattle

    DEFF Research Database (Denmark)

    Jalali, A.R.; Weisbjerg, Martin Riis; Nadeau, E.

    2015-01-01

    The effect of forage maturity stage at harvest, animal characteristics and neutral detergent fibre (NDF) intake on mean particle size and particle size distribution in faeces from sheep and cattle fed grass silages was studied (Study I). Models for prediction of faeces characteristics from sheep...... or restrictively with or without concentrate supplementation. The NDF content and acid detergent lignin (ADL) to NDF ratio of the forages ranged from 410 to 660 g/kg of dry matter (DM) and from 0.03 to 0.10, respectively, in Study I, and from 320 to 810 g/kg of DM and from 0.05 to 0.18, respectively, in Study II...... and this effect was amplified in larger animals. The prediction model established from Study I, on the effect of BW, ADL/NDF in forage, C:F and forage NDF intake on particle size in faeces of grass silage-fed animals in Study I appeared to be valid to predict the geometric mean particle size in faeces from goat...

  1. Fear of feces? Trade-offs between disease risk and foraging drive animal activity around raccoon latrines

    Science.gov (United States)

    Weinstein, Sara B.; Moura, Chad W.; Mendez, Jon Francis; Lafferty, Kevin D.

    2017-01-01

    Fear of predation alters prey behavior, which can indirectly alter entire landscapes. A parasite-induced ecology of fear might also exist if animals avoid parasite-contaminated resources when infection costs outweigh foraging benefits. To investigate whether animals avoid parasite contaminated sites, and if such avoidance balances disease costs and foraging gains, we monitored animal behavior at raccoon latrines – sites that concentrate both seeds and pathogenic parasite eggs. Using wildlife cameras, we documented over 40 potentially susceptible vertebrate species in latrines and adjacent habitat. Latrine contact rates reflected background activity, diet preferences and disease risk. Disease-tolerant raccoons and rats displayed significant site attraction, while susceptible birds and small mammals avoided these high-risk sites. This suggests that parasites, like predators, might create a landscape of fear for vulnerable hosts. Such non-consumptive parasite effects could alter disease transmission, population dynamics, and even ecosystem structure.

  2. Overturning conclusions of Lévy flight movement patterns by fishing boats and foraging animals.

    Science.gov (United States)

    Edwards, Andrew M

    2011-06-01

    A surprisingly diverse variety of foragers have previously been concluded to exhibit movement patterns known as Lévy flights, a special type of random walk. These foragers range in size from microzooplankton in experiments to fishermen in the Pacific Ocean and the North Sea. The Lévy flight conclusion implies that all the foragers have similar scale-free movement patterns that can be described by a single dimensionless parameter, the exponent micro of a power-law (Pareto) distribution. However, the previous conclusions have been made using methods that have since been shown to be problematic: inaccurate techniques were used to estimate micro, and the power-law distribution was usually assumed to hold without testing any alternative hypotheses. Therefore, I address the open question of whether the previous data still support the Lévy flight hypothesis, and thus determine whether Lévy flights really are so ubiquitous in ecology. I present a comprehensive reanalysis of 17 data sets from seven previous studies for which Lévy flight behavior had been concluded, covering marine, terrestrial, and experimental systems from four continents. I use the modern likelihood and Akaike weights approach to test whether simple alternative models are more supported by the data than Lévy flights. The previously estimated values of the power-law exponent micro do not match those calculated here using the accurate likelihood approach, and almost all of them lie outside of the likelihood-based 95% confidence intervals. Furthermore, the original power-law Lévy flight model is overwhelmingly rejected for 16 out of the 17 data sets when tested against three other simple models. For one data set, the data are consistent with coming from a bounded power-law distribution (a truncated Lévy flight). For three other data sets, an exponential distribution corresponding to a simple Poisson process is suitable. Thus, Lévy flight movement patterns are not the common phenomena that was once

  3. Herbage intake and animal performance of cattle grazing dwarf elaphant grass with two access times to a forage peanut area

    Directory of Open Access Journals (Sweden)

    Diego Melo de Liz

    2014-12-01

    Full Text Available Relatively short grazing periods in a pure legume pasture can be an alternative for increasing animal performance in medium-quality tropical pastures. Thus, the aim was to evaluate the herbage intake and animal performance of steers grazing dwarf elephant grass (Pennisetum purpureum Schum. cv. BRS Kurumi with two access times [2 h (07:00 - 9:00 and 6 h (07:00 - 13:00] to an area of forage peanut (Arachis pintoi cv. Amarillo. Twelve steers (219 ± 28.8 kg LW were divided into four groups and assessed during three consecutive grazing cycles, from January to March 2013. The crude protein and neutral detergent fiber contents were 158 and 577 g/kg dry matter (DM for dwarf elephant grass and 209 and 435 g/kg DM for forage peanut, respectively. The pre-grazing height and leaf mass of dwarf elephant grass and forage peanut were 94 cm and 2782 kg DM/ha and 15 cm and 1751 kg DM/ha, respectively. The herbage intake (mean = 2.7 ± 0.06% LW and average daily weight gain (mean = 1.16 ± 0.31 kg/day were similar for both treatments. However, animals with 2-h access to the legume paddock grazed for 71% of the time, whereas those with 6-h access grazed for 48% of the time. The performance of the steers that were allowed to graze forage peanut pasture for 2 h is similar to that of those that were allowed to graze the legume pasture for 6 h.

  4. Forage production and growing goats’ response under silvopastoral systems based on Guazuma ulmifolia, Leucaena leucocephala and Crescentia cujete

    Directory of Open Access Journals (Sweden)

    Gustavo Rodríguez Fernández

    2013-01-01

    Full Text Available Grass monoculture, besides being unnatural to goat’s natural eating habits, exhibits low forage production during the dry season, with negative impacts on animal productivity. This research aimed to determine the productive advantages of silvopastoral system arrangements in goat production. A completely randomized design with repeated measurements through time was used. Six treatments were evaluated: kikuyina grass monoculture (Bothriochloa pertusa and guinea grass monoculture (Panicum maximum cv. Tanzania as control groups; guacimo (Guazuma ulmifolia based silvopastoral arrangement; calabash (Crescentia cujete based silvopastoral arrangement; lead tree (Leucaena leucocephala based silvopastoral arrangement; and a mixed based silvopastoralarrangement (guacimo, calabash and leucaena. The information was processed with analysis of variance. The results showed increased forage production in silvopastoral arrangements vs. Bothriochloa pertusa monoculture. The greater increase in height (p <0.05 at 9-14 months of age, was obtained with the leucaena silvopastoral arrangement. All silvopastoral arrangements showed forage yield advantages compared to B. pertusa. The higher dry matter production of guinea grass is highlighted. Overall weight gain of the growing goats was low; nevertheless, a differential response between treatments was observed. Silvopastoral arrangements had the highest (p <0.05 weight gain (22.5 to 33.6 g/animal per day relative to the guinea grass monoculture (13.2 g/animal per day. The growing goats had higher percentages of estrus and pregnancy in the mixed system (66.7% and those based on guacimo (66.7% and on lead tree (55.6%.

  5. Forages and pastures symposium: managing the tall fescue-fungal endophyte symbiosis for optimum forage-animal production.

    Science.gov (United States)

    Aiken, G E; Strickland, J R

    2013-05-01

    Alkaloids produced by the fungal endophyte (Neotyphodium coenophialum) that infects tall fescue [Lolium arundinaceum (Schreb.) Darbysh.] are a paradox to cattle production. Although certain alkaloids impart tall fescue with tolerances to environmental stresses, such as moisture, heat, and herbivory, ergot alkaloids produced by the endophyte can induce fescue toxicosis, a malady that adversely affects animal production and physiology. Hardiness and persistence of tall fescue under limited management can be attributed to the endophyte, but the trade-off is reduced cattle production from consumption of ergot alkaloids produced by the endophyte. Improved understanding and knowledge of this endophyte-grass complex has facilitated development of technologies and management systems that can either mitigate or completely alleviate fescue toxicosis. This review discusses the research results that have led to development of 5 management approaches to either reduce the severity of fescue toxicosis or alleviate it altogether. Three approaches manipulate the endophyte-tall fescue complex to reduce or alleviate ergot alkaloids: 1) use of heavy grazing intensities, 2) replacing the toxic endophyte with nonergot alkaloid-producing endophytes, and 3) chemical suppression of seed head emergence. The remaining 2 management options do not affect ergot alkaloid concentrations in fescue tissues but are used 1) to avoid grazing of tall fescue with increased ergot alkaloid concentrations in the late spring and summer by moving cattle to warm-season grass pasture and 2) to dilute dietary alkaloids by interseeding clovers or feeding supplements.

  6. Endogenous nitrogen excretion by red kangaroos (Macropus rufus): effects of animal age and forage quality.

    Science.gov (United States)

    Munn, Adam J; Dawson, Terence J; Hume, Ian D

    2006-01-01

    Red kangaroos (Macropus rufus) are large (>20 kg) herbivorous marsupials common to arid and semiarid Australia. The population dynamics of red kangaroos are linked with environmental factors, operating largely through juvenile survival. A crucial period is the young-at-foot (YAF) stage, when juveniles have permanently left the mother's pouch but still take milk from a teat in the pouch. Forage quantity and quality have been implicated in drought-related mortalities of juvenile kangaroos. Here we compared how forage quality affected nitrogen (N) intake and excretion by YAF, weaned, and mature, nonlactating female red kangaroos. On high-quality forage (chopped lucerne hay, Medicago sativa) low in neutral-detergent fiber (43%+/-1%) and high in N (2.9%+/-0.1%), YAF and weaned kangaroos had ideal growth rates and retained 460-570 mg dietary N kg(-0.75) d(-1). But on poor-quality forage (chopped oaten hay, Avena sativa) high in neutral-detergent fiber (64%+/-1%) and low in N (0.9%+/-0.1%), YAF and weaned kangaroos could not sustain growth and were in negative N balance at -103+/-26 mg and -57+/-31 mg N kg(-0.75) d(-1), respectively. Notably, the YAF kangaroos excreted 64% of their truly digestible N intake from forage as nondietary fecal N (NDFN). By weaning age, the situation had improved, but the juveniles still lost 40% of their truly digestible N intake as NDFN compared with only 30% by the mature females. Our findings support field observations that forage quality, and not just quantity, is a major factor affecting the mortality of juvenile red kangaroos during drought.

  7. Improving the lipid nutritive value of poultry meat through the incorporation of a dehydrated leguminous-based forage in the diet for broiler chicks.

    Science.gov (United States)

    Ponte, P I P; Prates, J A M; Crespo, J P; Crespo, D G; Mourão, J L; Alves, S P; Bessa, R J B; Chaveiro-Soares, M A; Ferreira, L M A; Fontes, C M G A

    2008-08-01

    Dehydrated forages are assumed to be good sources of alpha-linolenic acid (ALA) and lipid-soluble antioxidant compounds (vitamin E homologs and beta-carotene). The effects of including a dehydrated leguminous-based forage in a typical diet for broiler chicken, on performance, meat quality, and fatty acid composition were evaluated. One hundred sixty 1-d-old male commercial broiler chicks (Ross 308) were housed in 20 battery brooders. During the 28-d growth period, the animals were fed ad libitum with a typical maize-soybean high-energy feed having access or not to a dehydrated leguminous-based forage provided in a separate feeder. The results revealed that dehydrated forage intake (which was 11.1% of the total intake) had no impact in broiler performance (P > 0.05). The capacity of ingested forage to modulate broiler meat fatty acid profile and the meat content in total cholesterol, tocopherols, tocotrienols, and beta-carotene was investigated in broiler chicks slaughtered at d 28. Dehydrated forage consumption had no effect on the lipid-soluble antioxidant compounds and cholesterol contents of broiler meat but had a significant effect on meat fatty acid profile. Although forage intake did not affect the linoleic acid and ALA contents in poultry meat, the levels of n-3 long-chain polyunsaturated fatty acids [eicosapentaenoic (P = 0.004), docosapentaenoic (P = 0.010), and docosahexaenoic (P = 0.007)] in breast meat were significantly higher in animals consuming leguminous biomass, which suggest a higher conversion of ALA into its derivatives in these birds. Overall, the data confirms that incorporation of a dehydrated leguminous-based forage in the diet for broiler chicks results in more favorable polyunsaturated fatty acids/saturated fatty acids and n-6/n-3 nutritional ratios for animals slaughtered at earlier stages of grow.

  8. Annual Forages: Influence on Animal Performance and Water/Nutrient Management

    Science.gov (United States)

    Annuals can provide short-term grazing between crop rotations or can be interseeded into perennial pastures to increase forage quality and productivity. They provide an opportunity to increase the economic and environmental sustainability of traditional grazing systems. However, to be profitable, an...

  9. Youden analysis of Karl Fischer titration data from an interlaboratory study determining water in animal feed, grain, and forage.

    Science.gov (United States)

    Jones, Frank E

    2005-01-01

    Data from a recent interlaboratory study of the determination of water (moisture) in animal feed, grain, and forage (plant tissue) by Karl Fischer titration were re-analyzed using Youden plots. The purpose was to show the unique ability these plots possess of separating random and systematic errors visually while providing numerical estimates of the precision and the systematic error of the method. Furthermore, the usefulness of the technique is underscored because AOAC INTERNATIONAL allows the use of matched pairs in collaborative studies to obtain estimates of repeatability and reproducibility.

  10. Modelling Pasture-based Automatic Milking System Herds: Grazeable Forage Options

    Directory of Open Access Journals (Sweden)

    M. R. Islam

    2015-05-01

    Full Text Available One of the challenges to increase milk production in a large pasture-based herd with an automatic milking system (AMS is to grow forages within a 1-km radius, as increases in walking distance increases milking interval and reduces yield. The main objective of this study was to explore sustainable forage option technologies that can supply high amount of grazeable forages for AMS herds using the Agricultural Production Systems Simulator (APSIM model. Three different basic simulation scenarios (with irrigation were carried out using forage crops (namely maize, soybean and sorghum for the spring-summer period. Subsequent crops in the three scenarios were forage rape over-sown with ryegrass. Each individual simulation was run using actual climatic records for the period from 1900 to 2010. Simulated highest forage yields in maize, soybean and sorghum- (each followed by forage rape-ryegrass based rotations were 28.2, 22.9, and 19.3 t dry matter/ha, respectively. The simulations suggested that the irrigation requirement could increase by up to 18%, 16%, and 17% respectively in those rotations in El-Niño years compared to neutral years. On the other hand, irrigation requirement could increase by up to 25%, 23%, and 32% in maize, soybean and sorghum based rotations in El-Nino years compared to La-Nina years. However, irrigation requirement could decrease by up to 8%, 7%, and 13% in maize, soybean and sorghum based rotations in La-Nina years compared to neutral years. The major implication of this study is that APSIM models have potentials in devising preferred forage options to maximise grazeable forage yield which may create the opportunity to grow more forage in small areas around the AMS which in turn will minimise walking distance and milking interval and thus increase milk production. Our analyses also suggest that simulation analysis may provide decision support during climatic uncertainty.

  11. Modelling Pasture-based Automatic Milking System Herds: Grazeable Forage Options

    Science.gov (United States)

    Islam, M. R.; Garcia, S. C.; Clark, C. E. F.; Kerrisk, K. L.

    2015-01-01

    One of the challenges to increase milk production in a large pasture-based herd with an automatic milking system (AMS) is to grow forages within a 1-km radius, as increases in walking distance increases milking interval and reduces yield. The main objective of this study was to explore sustainable forage option technologies that can supply high amount of grazeable forages for AMS herds using the Agricultural Production Systems Simulator (APSIM) model. Three different basic simulation scenarios (with irrigation) were carried out using forage crops (namely maize, soybean and sorghum) for the spring-summer period. Subsequent crops in the three scenarios were forage rape over-sown with ryegrass. Each individual simulation was run using actual climatic records for the period from 1900 to 2010. Simulated highest forage yields in maize, soybean and sorghum- (each followed by forage rape-ryegrass) based rotations were 28.2, 22.9, and 19.3 t dry matter/ha, respectively. The simulations suggested that the irrigation requirement could increase by up to 18%, 16%, and 17% respectively in those rotations in El-Niño years compared to neutral years. On the other hand, irrigation requirement could increase by up to 25%, 23%, and 32% in maize, soybean and sorghum based rotations in El-Nino years compared to La-Nina years. However, irrigation requirement could decrease by up to 8%, 7%, and 13% in maize, soybean and sorghum based rotations in La-Nina years compared to neutral years. The major implication of this study is that APSIM models have potentials in devising preferred forage options to maximise grazeable forage yield which may create the opportunity to grow more forage in small areas around the AMS which in turn will minimise walking distance and milking interval and thus increase milk production. Our analyses also suggest that simulation analysis may provide decision support during climatic uncertainty. PMID:25924963

  12. Determination of water (moisture) and dry matter in animal feed, grain, and forage (plant tissue) by Karl Fischer titration: collaborative study.

    Science.gov (United States)

    Thiex, Nancy J; Van Erem, Terri

    2002-01-01

    A Karl Fischer method for determining water (dry matter) in animal feed and forages was collaboratively studied. Water was extracted from animal feed or forage material into methanol-formamide (1 + 1) directly in the Karl Fischer titration vessel by high-speed homogenization. The water was titrated at 50 degrees C with one-component Karl Fischer reagent based on imidazole. Ten blind samples were sent to 9 collaborators in the United States, Canada, and Germany. The within-laboratory relative standard deviation (repeatability) ranged from 1.14 to 6.99% for water or from 0.09 to 0.56% for dry matter. Among-laboratory (including within-) relative standard deviation (reproducibility) ranged from 5.35 to 10.73%, or from 0.44 to 0.77% for dry matter. The authors recommend that the method be adopted as Official First Action by AOAC INTERNATIONAL. A comparable alternative extraction procedure using boiling methanol is also recommended for Official First Action.

  13. Food and animal characteristics relevant to the prediction of forage consumption and nutrient use in productive ruminants

    International Nuclear Information System (INIS)

    Oldham, J.D.; Eayres, H.; Emmans, G.C.; Hou, X.Z.; Illius, A.W.; Jessop, N.S.; Matthewman, R.W.

    1989-01-01

    A general model is presented of the relationships between animal and food characteristics which help lead to predictions of food consumption and animal performance. It is an important part of this scheme that equal weight is given to the description of food and animal characteristics. The results of some experiments are given suggesting that ruminants can select between feeds to meet their nutrient needs and that, in growing animals, the physical capacity to bite is an important determinant of grazing efficiency and ecology. Studies with growing lambs of the energetic efficiency of growth suggest that variation in the energy cost of protein accretion may be a more important determinant of overall energetic efficiency of growth than is conventionally supposed. In lactating animals that also exercise, milk protein and lactose yields fall during exercise and this effect is difficult to counteract by protein and/or starch supplementation of straw diets. Studies of forage substitution by supplements have not revealed differences in substitution rate with age in sheep. (author). 22 refs, 6 figs, 2 tabs

  14. Forage crops as substrate for animal feed and ethanol production in ...

    African Journals Online (AJOL)

    The results indicate the effect of harvesting time on their composition, including the contents of cellulose, lignin, and crude protein, thus affecting the ethanol yield and quality of animal feed. Ruzi grass, harvested 45 days after being planted, was shown to be the most suitable substrate for animal feed due to its highest crude ...

  15. Privatizing community animal health worker based veterinary ...

    African Journals Online (AJOL)

    Privatizing community animal health worker based veterinary services delivery system in West Kordofan, Southern Sudan; The needed roles of community animal health assistant (CAHA) and Pastoral unions.

  16. Foraging and fasting can influence contaminant concentrations in animals: an example with mercury contamination in a free-ranging marine mammal

    Science.gov (United States)

    Peterson, Sarah; Ackerman, Joshua T.; Crocker, Daniel E.; Costa, Daniel P.

    2018-01-01

    Large fluctuations in animal body mass in relation to life-history events can influence contaminant concentrations and toxicological risk. We quantified mercury concentrations in adult northern elephant seals (Mirounga angustirostris) before and after lengthy at sea foraging trips (n = 89) or fasting periods on land (n = 27), and showed that mercury concentrations in blood and muscle changed in response to these events. The highest blood mercury concentrations were observed after the breeding fast, whereas the highest muscle mercury concentrations were observed when seals returned to land to moult. Mean female blood mercury concentrations decreased by 30% across each of the two annual foraging trips, demonstrating a foraging-associated dilution of mercury concentrations as seals gained mass. Blood mercury concentrations increased by 103% and 24% across the breeding and moulting fasts, respectively, demonstrating a fasting-associated concentration of mercury as seals lost mass. In contrast to blood, mercury concentrations in female's muscle increased by 19% during the post-breeding foraging trip and did not change during the post-moulting foraging trip. While fasting, female muscle mercury concentrations increased 26% during breeding, but decreased 14% during moulting. Consequently, regardless of exposure, an animal's contaminant concentration can be markedly influenced by their annual life-history events.

  17. A Remote Sensing Based Forage Biomass Yield Inversion Model of Alpine-cold Meadow during Grass-withering Period in Sanjiangyuan Area

    International Nuclear Information System (INIS)

    Song, Weize; Jia, Haifeng; Liang, Shidong; Wang, Zheng; Liu, Shujie; Hao, Lizhuang; Chai, Shatuo

    2014-01-01

    Estimating forage biomass yield remotely from space is still challenging nowadays. Field experiments were conducted and ground measurements correlated to remote sensing data to estimate the forage biomass yield of Alpine-cold meadow grassland during the grass and grass-withering period in Sanjiangyuan area in Yushu county. Both Shapiro-Wilk and Kolmogorov-Smirnov two-tailed tests showed that the field training samples are normally distributed, the Spearman coefficient indicated that the parametric correlation analysis had significant differences. The optimal regression models were developed based on the Landsat Thematic Mapper Normalized Difference Vegetation Index (TM-NDVI) and the forage biomass field data during the grass and the grass-withering periods, respectively. Then an integration model was used to predict forage biomass yield of alpine-cold meadow in the grass-withering period. The model showed good prediction accuracy and reliability. It was found that this approach can not only estimate forage yield in large scale efficiently but also overcome the seasonal limitation of remote sensing inversion. This technique can provides valuable guidance to animal husbandry to resource more efficiently in winter

  18. Valor nutritivo da forragem e produção animal em pastagens de Brachiaria brizantha Forage nutritive value and animal production in Brachiaria brizantha pastures

    Directory of Open Access Journals (Sweden)

    Valéria Pacheco Batista Euclides

    2009-01-01

    Full Text Available O objetivo deste trabalho foi avaliar a produção animal e sua relação com as características dos pastos de Brachiaria brizantha cultivares Marandu, Xaraés e Piatã. O delineamento experimental foi o de blocos ao acaso, com três tratamentos e duas repetições. Os piquetes com 2 ha foram subdivididos em dois e submetidos ao pastejo alternado, com 28 dias de utilização e 28 dias de descanso. Foram utilizados três novilhos teste, por piquete, e novilhos reguladores para manter resíduos pós pastejo em torno de 3 Mg ha-1 de matéria seca. Mensalmente, os pastos foram avaliados para se estimar o valor nutritivo da forragem. Os animais foram pesados, e as taxas de lotação foram ajustadas duas vezes por semana. No pasto da cv. Xaraés, apesar do menor ganho médio diário (GMD dos animais, a taxa de lotação foi maior, o que resultou em maior produtividade da cv. Xaraés, em comparação às cvs. Marandu e Piatã. No pasto da cv. Piatã, houve aumento do GMD, o que indica que as cvs. Xaraés e Piatã são novas alternativas para a diversificação dos pastos no Cerrado. Assim, a escolha da forragem deve se dar em razão da meta do sistema de produção, ou seja, a produção por animal ou por área.The objectives of this work were to evaluate animal production and its relationship with pasture characteristics of Brachiaria brizantha cultivars Marandu, Xaraés and Piatã. The experiment had a randomized complete block design, with three treatments and two replicates. Two-ha paddocks were divided into two and submitted to alternated grazing, with 28 days of grazing and 28 days of rest. Three tester steers were kept in each paddock; additional steers were placed in each paddock by the put and take technique, to assure post grazing residues of about 3 Mg ha-1 of dry matter. The pastures were sampled monthly to estimate the nutritive value of the forage. The animals were weighted, and the stocking rate was adjusted twice a week. Despite the

  19. Forages and pastures symposium: Animal performance and environmental efficiency of cool-and warm-season annual grazing systems

    Science.gov (United States)

    Annual forage crops can provide short-term grazing between crop rotations or can be interseeded into perennial pastures to increase forage quality and productivity. They also provide an opportunity to increase the economic and environmental sustainability of traditional grazing systems. Cool-season ...

  20. 7 CFR 1437.401 - Forage.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false Forage. 1437.401 Section 1437.401 Agriculture... Coverage of Forage Intended for Animal Consumption § 1437.401 Forage. (a) Forage eligible for benefits... operation in three or more of the last five crop years, except producers who have not produced forage for...

  1. Groundwater phosphorus in forage-based landscape with cow-calf operation.

    Science.gov (United States)

    Sigua, Gilbert C; Chase, Chad C

    2014-02-01

    Forage-based cow-calf operations may have detrimental impacts on the chemical status of groundwater and streams and consequently on the ecological and environmental status of surrounding ecosystems. Assessing and controlling phosphorus (P) inputs are, thus, considered the key to reducing eutrophication and managing ecological integrity. In this paper, we monitored and evaluated P concentrations of groundwater (GW) compared to the concentration of surface water (SW) P in forage-based landscape with managed cow-calf operations for 3 years (2007-2009). Groundwater samples were collected from three landscape locations along the slope gradient (GW1 10-30% slope, GW2 5-10% slope, and GW3 0-5% slope). Surface water samples were collected from the seepage area (SW 0% slope) located at the bottom of the landscape. Of the total P collected (averaged across year) in the landscape, 62.64% was observed from the seepage area or SW compared with 37.36% from GW (GW1 = 8.01%; GW2 = 10.92%; GW3 = 18.43%). Phosphorus in GW ranged from 0.02 to 0.20 mg L(-1) while P concentration in SW ranged from 0.25 to 0.71 mg L(-1). The 3-year average of P in GW of 0.09 mg L(-1) was lower than the recommended goal or the Florida's numeric nutrients standards (NNS) of 0.12 mg P L(-1). The 3-year average of P concentration in SW of 0.45 mg L(-1) was about fourfold higher than the Florida's NNS value. Results suggest that cow-calf operation in pasture-based landscape would contribute more P to SW than in the GW. The risk of GW contamination by P from animal agriculture production system is limited, while the solid forms of P subject to loss via soil erosion could be the major water quality risk from P.

  2. An individual-based, spatial foraging model for cadmium accumulation in diving ducks

    Energy Technology Data Exchange (ETDEWEB)

    Lovvorn, J.R.; Gillingham, M.P. [Univ. of Wyoming, Laramie, WY (United States). Dept. of Zoology and Physiology

    1994-12-31

    Contaminant studies of migratory birds include two main approaches: (1) collecting wild birds and analyzing their tissues, and (2) toxicity assays with captive birds. The first approach has shortcomings for these highly mobile animals--one seldom knows their length of stay in the area, and sites are often in urban environments where shooting is problematic. The second approach with captive birds ignores changes in food intake with varying activity and weather experienced by wild birds, and greater toxic consequences under multiple environmental stresses. Neither of these approaches alone can predict maximum allowable contaminant levels in foods that preclude toxic effects under different field conditions, or what body burdens accumulate during varying lengths of stay and affect the birds` biology at other places and times. To allow such predictions, the authors developed an individual-based model for intake of benthic foods by diving ducks for varying weather, water depth, food dispersion, and nutrient content of food. Food-intake estimates are combined with laboratory data on contaminant uptake as a function of food consumption and contaminant content. As an example, the authors estimate cadmium uptake by canvas back ducks foraging on below ground tubers of the submerged plant Vallisneria americans. They then show how their model can be used to include avian benthiovores in aquatic food web models for ecological risk assessment.

  3. Ecosystem-based management objectives for the North Sea: riding the forage fish rollercoaster

    DEFF Research Database (Denmark)

    Dickey-Collas, Mark; Engelhard, Georg H.; Rindorf, Anna

    2014-01-01

    The North Sea provides a useful model for considering forage fish (FF) within ecosystem-based management as it has a complex assemblage of FF species. This paper is designed to encourage further debate and dialogue between stakeholders about management objectives. Changing the management of fishe...

  4. Estimation of the duodenal flow of microbial nitrogen in ruminants based on the chemical composition of forages: a literature review

    NARCIS (Netherlands)

    Gosselink, J.M.J.; Poncet, C.; Dulphy, J.P.; Cone, J.W.

    2003-01-01

    The objective of this study was to evaluate the estimation of the duodenal flow of microbial nitrogen (N) in ruminants fed forage only, per kilogram of dry matter (DM) intake, which is the yield of microbial protein (YMP). The estimation was based on the chemical composition of forages. A data file

  5. Review on Mycotoxin Issues in Ruminants: Occurrence in Forages, Effects of Mycotoxin Ingestion on Health Status and Animal Performance and Practical Strategies to Counteract Their Negative Effects

    Science.gov (United States)

    Gallo, Antonio; Giuberti, Gianluca; Frisvad, Jens C.; Bertuzzi, Terenzio; Nielsen, Kristian F.

    2015-01-01

    Ruminant diets include cereals, protein feeds, their by-products as well as hay and grass, grass/legume, whole-crop maize, small grain or sorghum silages. Furthermore, ruminants are annually or seasonally fed with grazed forage in many parts of the World. All these forages could be contaminated by several exometabolites of mycotoxigenic fungi that increase and diversify the risk of mycotoxin exposure in ruminants compared to swine and poultry that have less varied diets. Evidence suggests the greatest exposure for ruminants to some regulated mycotoxins (aflatoxins, trichothecenes, ochratoxin A, fumonisins and zearalenone) and to many other secondary metabolites produced by different species of Alternaria spp. (e.g., AAL toxins, alternariols, tenuazonic acid or 4Z-infectopyrone), Aspergillus flavus (e.g., kojic acid, cyclopiazonic acid or β-nitropropionic acid), Aspergillus fuminatus (e.g., gliotoxin, agroclavine, festuclavines or fumagillin), Penicillium roqueforti and P. paneum (e.g., mycophenolic acid, roquefortines, PR toxin or marcfortines) or Monascus ruber (citrinin and monacolins) could be mainly related to forage contamination. This review includes the knowledge of mycotoxin occurrence reported in the last 15 years, with special emphasis on mycotoxins detected in forages, and animal toxicological issues due to their ingestion. Strategies for preventing the problem of mycotoxin feed contamination under farm conditions are discussed. PMID:26274974

  6. Review on Mycotoxin Issues in Ruminants: Occurrence in Forages, Effects of Mycotoxin Ingestion on Health Status and Animal Performance and Practical Strategies to Counteract Their Negative Effects.

    Science.gov (United States)

    Gallo, Antonio; Giuberti, Gianluca; Frisvad, Jens C; Bertuzzi, Terenzio; Nielsen, Kristian F

    2015-08-12

    Ruminant diets include cereals, protein feeds, their by-products as well as hay and grass, grass/legume, whole-crop maize, small grain or sorghum silages. Furthermore, ruminants are annually or seasonally fed with grazed forage in many parts of the World. All these forages could be contaminated by several exometabolites of mycotoxigenic fungi that increase and diversify the risk of mycotoxin exposure in ruminants compared to swine and poultry that have less varied diets. Evidence suggests the greatest exposure for ruminants to some regulated mycotoxins (aflatoxins, trichothecenes, ochratoxin A, fumonisins and zearalenone) and to many other secondary metabolites produced by different species of Alternaria spp. (e.g., AAL toxins, alternariols, tenuazonic acid or 4Z-infectopyrone), Aspergillus flavus (e.g., kojic acid, cyclopiazonic acid or β-nitropropionic acid), Aspergillus fuminatus (e.g., gliotoxin, agroclavine, festuclavines or fumagillin), Penicillium roqueforti and P. paneum (e.g., mycophenolic acid, roquefortines, PR toxin or marcfortines) or Monascus ruber (citrinin and monacolins) could be mainly related to forage contamination. This review includes the knowledge of mycotoxin occurrence reported in the last 15 years, with special emphasis on mycotoxins detected in forages, and animal toxicological issues due to their ingestion. Strategies for preventing the problem of mycotoxin feed contamination under farm conditions are discussed.

  7. Review on Mycotoxin Issues in Ruminants: Occurrence in Forages, Effects of Mycotoxin Ingestion on Health Status and Animal Performance and Practical Strategies to Counteract Their Negative Effects

    Directory of Open Access Journals (Sweden)

    Antonio Gallo

    2015-08-01

    Full Text Available Ruminant diets include cereals, protein feeds, their by-products as well as hay and grass, grass/legume, whole-crop maize, small grain or sorghum silages. Furthermore, ruminants are annually or seasonally fed with grazed forage in many parts of the World. All these forages could be contaminated by several exometabolites of mycotoxigenic fungi that increase and diversify the risk of mycotoxin exposure in ruminants compared to swine and poultry that have less varied diets. Evidence suggests the greatest exposure for ruminants to some regulated mycotoxins (aflatoxins, trichothecenes, ochratoxin A, fumonisins and zearalenone and to many other secondary metabolites produced by different species of Alternaria spp. (e.g., AAL toxins, alternariols, tenuazonic acid or 4Z-infectopyrone, Aspergillus flavus (e.g., kojic acid, cyclopiazonic acid or β-nitropropionic acid, Aspergillus fuminatus (e.g., gliotoxin, agroclavine, festuclavines or fumagillin, Penicillium roqueforti and P. paneum (e.g., mycophenolic acid, roquefortines, PR toxin or marcfortines or Monascus ruber (citrinin and monacolins could be mainly related to forage contamination. This review includes the knowledge of mycotoxin occurrence reported in the last 15 years, with special emphasis on mycotoxins detected in forages, and animal toxicological issues due to their ingestion. Strategies for preventing the problem of mycotoxin feed contamination under farm conditions are discussed.

  8. Optimal Foraging in Semantic Memory

    Science.gov (United States)

    Hills, Thomas T.; Jones, Michael N.; Todd, Peter M.

    2012-01-01

    Do humans search in memory using dynamic local-to-global search strategies similar to those that animals use to forage between patches in space? If so, do their dynamic memory search policies correspond to optimal foraging strategies seen for spatial foraging? Results from a number of fields suggest these possibilities, including the shared…

  9. Animal-borne imaging reveals novel insights into the foraging behaviors and Diel activity of a large-bodied apex predator, the American alligator (Alligator mississippiensis.

    Directory of Open Access Journals (Sweden)

    James C Nifong

    Full Text Available Large-bodied, top- and apex predators (e.g., crocodilians, sharks, wolves, killer whales can exert strong top-down effects within ecological communities through their interactions with prey. Due to inherent difficulties while studying the behavior of these often dangerous predatory species, relatively little is known regarding their feeding behaviors and activity patterns, information that is essential to understanding their role in regulating food web dynamics and ecological processes. Here we use animal-borne imaging systems (Crittercam to study the foraging behavior and activity patterns of a cryptic, large-bodied predator, the American alligator (Alligator mississippiensis in two estuaries of coastal Florida, USA. Using retrieved video data we examine the variation in foraging behaviors and activity patterns due to abiotic factors. We found the frequency of prey-attacks (mean = 0.49 prey attacks/hour as well as the probability of prey-capture success (mean = 0.52 per attack were significantly affected by time of day. Alligators attempted to capture prey most frequently during the night. Probability of prey-capture success per attack was highest during morning hours and sequentially lower during day, night, and sunset, respectively. Position in the water column also significantly affected prey-capture success, as individuals' experienced two-fold greater success when attacking prey while submerged. These estimates are the first for wild adult American alligators and one of the few examples for any crocodilian species worldwide. More broadly, these results reveal that our understandings of crocodilian foraging behaviors are biased due to previous studies containing limited observations of cryptic and nocturnal foraging interactions. Our results can be used to inform greater understanding regarding the top-down effects of American alligators in estuarine food webs. Additionally, our results highlight the importance and power of using animal

  10. Animal-borne imaging reveals novel insights into the foraging behaviors and Diel activity of a large-bodied apex predator, the American alligator (Alligator mississippiensis).

    Science.gov (United States)

    Nifong, James C; Nifong, Rachel L; Silliman, Brian R; Lowers, Russell H; Guillette, Louis J; Ferguson, Jake M; Welsh, Matthew; Abernathy, Kyler; Marshall, Greg

    2014-01-01

    Large-bodied, top- and apex predators (e.g., crocodilians, sharks, wolves, killer whales) can exert strong top-down effects within ecological communities through their interactions with prey. Due to inherent difficulties while studying the behavior of these often dangerous predatory species, relatively little is known regarding their feeding behaviors and activity patterns, information that is essential to understanding their role in regulating food web dynamics and ecological processes. Here we use animal-borne imaging systems (Crittercam) to study the foraging behavior and activity patterns of a cryptic, large-bodied predator, the American alligator (Alligator mississippiensis) in two estuaries of coastal Florida, USA. Using retrieved video data we examine the variation in foraging behaviors and activity patterns due to abiotic factors. We found the frequency of prey-attacks (mean = 0.49 prey attacks/hour) as well as the probability of prey-capture success (mean = 0.52 per attack) were significantly affected by time of day. Alligators attempted to capture prey most frequently during the night. Probability of prey-capture success per attack was highest during morning hours and sequentially lower during day, night, and sunset, respectively. Position in the water column also significantly affected prey-capture success, as individuals' experienced two-fold greater success when attacking prey while submerged. These estimates are the first for wild adult American alligators and one of the few examples for any crocodilian species worldwide. More broadly, these results reveal that our understandings of crocodilian foraging behaviors are biased due to previous studies containing limited observations of cryptic and nocturnal foraging interactions. Our results can be used to inform greater understanding regarding the top-down effects of American alligators in estuarine food webs. Additionally, our results highlight the importance and power of using animal-borne imaging when

  11. Foraging on the potential energy surface: a swarm intelligence-based optimizer for molecular geometry.

    Science.gov (United States)

    Wehmeyer, Christoph; Falk von Rudorff, Guido; Wolf, Sebastian; Kabbe, Gabriel; Schärf, Daniel; Kühne, Thomas D; Sebastiani, Daniel

    2012-11-21

    We present a stochastic, swarm intelligence-based optimization algorithm for the prediction of global minima on potential energy surfaces of molecular cluster structures. Our optimization approach is a modification of the artificial bee colony (ABC) algorithm which is inspired by the foraging behavior of honey bees. We apply our modified ABC algorithm to the problem of global geometry optimization of molecular cluster structures and show its performance for clusters with 2-57 particles and different interatomic interaction potentials.

  12. Speed and Displacement Control System of Bearingless Brushless DC Motor Based on Improved Bacterial Foraging Algorithm

    Directory of Open Access Journals (Sweden)

    Diao Xiaoyan

    2016-01-01

    Full Text Available To solve the deficiencies of long optimization time and poor precision existing in conventional bacterial foraging algorithm (BFA in the process of parameter optimization, an improved bacterial foraging algorithm (IBFA is proposed and applied to speed and displacement control system of bearingless brushless DC (Bearingless BLDC motors. To begin with the fundamental principle of BFA, the proposed method is introduced and the individual intelligence is efficiently used in the process of parameter optimization, and then the working principle of bearingless BLDC motors is expounded. Finally, modeling and simulation of the speed and displacement control system of bearingless BLDC motors based on the IBFA are carried out by taking the software of MATLAB/Simulink as a platform. Simulation results show that, speed overshoot, torque ripple and rotor position oscillation are dramatically reduced, thus the proposed method has good application prospects in the field of bearingless motors.

  13. Forage production and growing goats’ response under silvopastoral systems based on Guazuma ulmifolia, Leucaena leucocephala and Crescentia cujete

    OpenAIRE

    Gustavo Rodríguez Fernández; Belisario Roncallo Fandiño

    2013-01-01

    Grass monoculture, besides being unnatural to goat’s natural eating habits, exhibits low forage production during the dry season, with negative impacts on animal productivity. This research aimed to determine the productive advantages of silvopastoral system arrangements in goat production. A completely randomized design with repeated measurements through time was used. Six treatments were evaluated: kikuyina grass monoculture (Bothriochloa per...

  14. Ethics in Animal-Based Research.

    Science.gov (United States)

    Gross, Dominik; Tolba, René H

    2015-01-01

    In recent years, there have been a number of new demands and regulations which have reignited the discussion on ethics in animal-based research. In the light of this development, the present review first presents an overview of underlying core ethical questions and issues. This is followed by an outline of the current discussion on whether animals (used for experimentation) should have rights ascribed to them and whether animals need to have certain characteristics in order to be the beneficiaries of rights. The discourse on concepts of sentience and the 'sociozoological scale' in particular is mapped out in this regard. There follows an outline of relevant ethical positions and current moral approaches to animal-based research (animal rights position, utilitarianism, 'convergence position', intrinsic cultural value of fundamental research, 'contractarianism', anthropocentrism, principle of the three Rs). 2015 S. Karger AG, Basel.

  15. Animal-based measures for welfare assessment

    Directory of Open Access Journals (Sweden)

    Agostino Sevi

    2010-01-01

    Full Text Available Animal welfare assessment can’t be irrespective of measures taken on animals. Indeed, housing parametersrelatedtostructures, designandmicro-environment, evenifreliable parameters related to structures, design and micro-environment, even if reliable and easier to take, can only identify conditions which could be detrimental to animal welfare, but can’t predict poor welfare in animals per se. Welfare assessment through animal-based measures is almost complex, given that animals’ responses to stressful conditions largely depend on the nature, length and intensity of challenges and on physiological status, age, genetic susceptibility and previous experience of animals. Welfare assessment requires a multi-disciplinary approach and the monitoring of productive, ethological, endocrine, immunological and pathological param- eters to be exhaustive and reliable. So many measures are needed, because stresses can act only on some of the mentioned parameters or on all of them but at different times and degree. Under this point of view, the main aim of research is to find feasible and most responsive indicators of poor animal welfare. In last decades, studies focused on the following parameters for animal wel- fare assessment indexes of biological efficiency, responses to behavioral tests, cortisol secretion, neutrophil to lymphocyte ratio, lymphocyte proliferation, production of antigen specific IgG and cytokine release, somatic cell count and acute phase proteins. Recently, a lot of studies have been addressed to reduce handling and constraint of animals for taking measures to be used in welfare assessment, since such procedures can induce stress in animals and undermined the reliability of measures taken for welfare assessment. Range of animal-based measures for welfare assessment is much wider under experimental condition than at on-farm level. In welfare monitoring on-farm the main aim is to find feasible measures of proved validity and reliability

  16. Produção animal e vegetal em pastagem nativa manejada sob diferentes ofertas de forragem por bovinos Animal and vegetal production of a natural pasture under different forage allowances for cattle

    Directory of Open Access Journals (Sweden)

    Jean Carlos Mezzalira

    2012-07-01

    Full Text Available Neste trabalho avaliou-se a influência de diferentes ofertas de forragem e suas combinações ao longo do ano sobre a dinâmica do crescimento da pastagem e o desempenho animal. O experimento foi conduzido em área de pastagem natural com novilhas de sobreano mantidas em pastejo contínuo com taxa de lotação variável. Os tratamentos foram ofertas de forragem fixas ao longo do ano: 4; 8; 12 e 16kg de matéria seca 100kg de peso vivo-1 por dia e combinações de 8 na primavera e 12 no outono-inverno-verão (8-12%; 12 na primavera e 8 no outono-inverno-verão (12-8%; 16 na primavera e 12 no outono-inverno-verão (16-12%, constituindo um delineamento experimental de blocos casualizados com duas repetições. A produção de forragem e o ganho de peso animal foram medidos na estação de crescimento de 2007-2008. Os resultados comprovaram que o uso de oferta de forragem muito baixa, como 4%, prejudica o desempenho animal individual e por área. O manejo combinado de ofertas 8-12% promoveu aumento de 35% no desempenho individual (0,345kg animal-1 aumento de 20% na produção por área (209kg ha-1 de PV em comparação ao manejo 12% ao longo do ano.In this research it was evaluated the influence of different forage allowances and combinations of forage allowances along the year on the pasture accumulation dynamic and animal performance. The experiment was conducted in a natural pasture area with yearling beef heifers maintained in continuous grazing with variable stocking rate. The treatments utilized with fixed forage allowances during the year were 4; 8; 12 e 16kg 100kg-1 of live weight; and the treatments of forage allowance combinations were 8 on Spring and 12 on Autumn-Winter-Summer (8-12%; 12 on Spring and 8 on Autumn-Winter-Summer (12-8%; 16 on Spring and 12 on Autumn-Winter-Summer (16-12%, constituting a experimental design in randomized blocks with two replicates of area. The primary and secondary productions were evaluated on the

  17. [Study on foraging behaviors of honeybee Apis mellifera based on RFID technology].

    Science.gov (United States)

    Tian, Liu-Qing; He, Xu-Jiang; Wu, Xiao-Bo; Gan, Hai-Yan; Han, Xu; Liu, Hao; Zeng, Zhi-Jiang

    2014-03-01

    Honeybee foragers can flexibly adjust their out-hive activities to ensure growth and reproduction of the colony. In order to explore the characteristics of honey bees foraging behaviors, in this study, their flight activities were monitored 24 hours per day for a duration of 38 days, using an radio frequency identification (RFID) system designed and manufactured by the Honeybee Research Institute of Jiangxi Agricultural University in cooperation with the Guangzhou Invengo Information Technology Co., Ltd. Our results indicated that 63.4% and 64.5% of foragers were found rotating more than one day off during the foraging period in two colonies, and 22.5% and 26.4% of the total foraging days were used for rest respectively. Further, although the total foraging time between rotating day-off foragers and continuously working foragers was equal, the former had a significant longer lifespan than the latter. Additionally, the lifespan of the early developed foragers was significantly lower than that of the normally developed foragers. This study enriched the content of foraging behaviors of honey bees, and it could be used as the basis for the further explorations on evolutionary mechanism of foraging behaviors of eusocial insects.

  18. Multi Dimensional Honey Bee Foraging Algorithm Based on Optimal Energy Consumption

    Science.gov (United States)

    Saritha, R.; Vinod Chandra, S. S.

    2017-10-01

    In this paper a new nature inspired algorithm is proposed based on natural foraging behavior of multi-dimensional honey bee colonies. This method handles issues that arise when food is shared from multiple sources by multiple swarms at multiple destinations. The self organizing nature of natural honey bee swarms in multiple colonies is based on the principle of energy consumption. Swarms of multiple colonies select a food source to optimally fulfill the requirements of its colonies. This is based on the energy requirement for transporting food between a source and destination. Minimum use of energy leads to maximizing profit in each colony. The mathematical model proposed here is based on this principle. This has been successfully evaluated by applying it on multi-objective transportation problem for optimizing cost and time. The algorithm optimizes the needs at each destination in linear time.

  19. Agent-based simulation of animal behaviour

    NARCIS (Netherlands)

    C.M. Jonker (Catholijn); J. Treur

    1998-01-01

    textabstract In this paper it is shown how animal behaviour can be simulated in an agent-based manner. Different models are shown for different types of behaviour, varying from purely reactive behaviour to pro-active, social and adaptive behaviour. The compositional development method for

  20. Produção animal e valor nutritivo da forragem de pastagem de coastcross consorciada com amendoim forrageiro Animal production and nutritive value of a coastcross pasture mixed with forage peanut

    Directory of Open Access Journals (Sweden)

    L.M. Barbero

    2010-06-01

    Full Text Available Neste estudo foram utilizados os tratamentos: coastcross + amendoim forrageiro + 200kg/ha de N; coastcross + amendoim forrageiro + 100kg/ha de N; coastcross + 200kg/ha de N e coastcross + amendoim forrageiro (parcelas no inverno, primavera, verão e outono (sub parcelas, delineados em blocos ao acaso. Novilhas foram manejadas sob lotação contínua e taxa de lotação variável em pastagem mantida a 17cm de altura. Amostras foram coletadas a cada 28 dias para determinar o valor nutritivo da forragem. Foram avaliados: ganho médio diário (GMD, ganho de peso vivo (GPV, taxa de lotação (TL e número de animais dia (NAD. Quanto ao valor nutritivo da forragem, os piores resultados ocorreram nas pastagens sem adubação, 16,9% e 6,0% de PB de folha e colmo, respectivamente, e 70,1 % de FDN de folha. Na primavera e no verão, o GMD foi mais alto, 0,518 e 0,515kg/animal do que no inverno e outono, 0,396 e 0,293kg/animal, respectivamente. A TL foi superior nas pastagens que receberam a maior dose de nitrogênio, 5,38UA/ha em média, e no verão, 6,81UA/ha. O GPV foi mais elevado nas áreas com adubação, 1341kg de PV/ha, em relação aos pastos não adubados, 735kg/ha.In this study, the following treatments were used: coastcross + forage peanut + 200kg/ha of N; coastcross + forage peanut + 100kg/ha of N; coastcross + 200kg/ha of N and coastcross + forage peanut (plots in the winter, spring, summer, and autumn (subplots, designed in randomized blocks. Heifers were managed under continuous stocking and variable stocking rate on pasture maintained at 17cm height. Samples were collected every 28 days determining the nutritional value of forage. Average daily gain (ADG, weight gain (WG, stocking rate (SR, and number of animals/day (NAD were evaluated. As for forage nutritional value, the worst results were found in pasture without fertilization, 16.9% and 6.0% CP of leaf and stem, respectively, and 70.1% NDF in leaves. In the spring and summer, animals

  1. Hybrid Artificial Root Foraging Optimizer Based Multilevel Threshold for Image Segmentation

    Directory of Open Access Journals (Sweden)

    Yang Liu

    2016-01-01

    Full Text Available This paper proposes a new plant-inspired optimization algorithm for multilevel threshold image segmentation, namely, hybrid artificial root foraging optimizer (HARFO, which essentially mimics the iterative root foraging behaviors. In this algorithm the new growth operators of branching, regrowing, and shrinkage are initially designed to optimize continuous space search by combining root-to-root communication and coevolution mechanism. With the auxin-regulated scheme, various root growth operators are guided systematically. With root-to-root communication, individuals exchange information in different efficient topologies, which essentially improve the exploration ability. With coevolution mechanism, the hierarchical spatial population driven by evolutionary pressure of multiple subpopulations is structured, which ensure that the diversity of root population is well maintained. The comparative results on a suit of benchmarks show the superiority of the proposed algorithm. Finally, the proposed HARFO algorithm is applied to handle the complex image segmentation problem based on multilevel threshold. Computational results of this approach on a set of tested images show the outperformance of the proposed algorithm in terms of optimization accuracy computation efficiency.

  2. Challenges and opportunities for improving eco-efficiency of tropical forage-based systems to mitigate greenhouse gas emissions

    Directory of Open Access Journals (Sweden)

    Michael Peters

    2013-12-01

    Full Text Available Forage-based livestock production plays a key role in national and regional economies, for food security and poverty alleviation, but is considered a major contributor to agricultural GHG emissions. While demand for livestock products is predicted to increase, there is political and societal pressure both to reduce environmental impacts and to convert some of the pasture area to alternative uses, such as crop production and environmental conservation. Thus, it is essential to develop approaches for sustainable intensification of livestock systems to mitigate GHG emissions, addressing biophysical, socio-economic and policy challenges. This paper highlights the potential of improved tropical forages, linked with policy incentives, to enhance livestock production, while reducing its environmental footprint. Emphasis is on crop-livestock systems. We give examples for sustainable intensification to mitigate GHG emissions, based on improved forages in Brazil and Colombia, and suggest future perspectives.

  3. Computer Animation Based on Particle Methods

    Directory of Open Access Journals (Sweden)

    Rafal Wcislo

    1999-01-01

    Full Text Available The paper presents the main issues of a computer animation of a set of elastic macroscopic objects based on the particle method. The main assumption of the generated animations is to achieve very realistic movements in a scene observed on the computer display. The objects (solid bodies interact mechanically with each other, The movements and deformations of solids are calculated using the particle method. Phenomena connected with the behaviour of solids in the gravitational field, their defomtations caused by collisions and interactions with the optional liquid medium are simulated. The simulation ofthe liquid is performed using the cellular automata method. The paper presents both simulation schemes (particle method and cellular automata rules an the method of combining them in the single animation program. ln order to speed up the execution of the program the parallel version based on the network of workstation was developed. The paper describes the methods of the parallelization and it considers problems of load-balancing, collision detection, process synchronization and distributed control of the animation.

  4. Bringing Home the Trash: Do Colony-Based Differences in Foraging Distribution Lead to Increased Plastic Ingestion in Laysan Albatrosses?

    Science.gov (United States)

    Young, Lindsay C.; Vanderlip, Cynthia; Duffy, David C.; Afanasyev, Vsevolod; Shaffer, Scott A.

    2009-01-01

    When searching for prey, animals should maximize energetic gain, while minimizing energy expenditure by altering their movements relative to prey availability. However, with increasing amounts of marine debris, what once may have been ‘optimal’ foraging strategies for top marine predators, are leading to sub-optimal diets comprised in large part of plastic. Indeed, the highly vagile Laysan albatross (Phoebastria immutabilis) which forages throughout the North Pacific, are well known for their tendency to ingest plastic. Here we examine whether Laysan albatrosses nesting on Kure Atoll and Oahu Island, 2,150 km apart, experience different levels of plastic ingestion. Twenty two geolocators were deployed on breeding adults for up to two years. Regurgitated boluses of undigestable material were also collected from chicks at each site to compare the amount of plastic vs. natural foods. Chicks from Kure Atoll were fed almost ten times the amount of plastic compared to chicks from Oahu despite boluses from both colonies having similar amounts of natural food. Tracking data indicated that adults from either colony did not have core overlapping distributions during the early half of the breeding period and that adults from Kure had a greater overlap with the putative range of the Western Garbage Patch corroborating our observation of higher plastic loads at this colony. At-sea distributions also varied throughout the year suggesting that Laysan albatrosses either adjusted their foraging behavior according to constraints on time away from the nest or to variation in resources. However, in the non-breeding season, distributional overlap was greater indicating that the energy required to reach the foraging grounds was less important than the total energy available. These results demonstrate how a marine predator that is not dispersal limited alters its foraging strategy throughout the reproductive cycle to maximize energetic gain and how this has led to differences in

  5. Bringing home the trash: do colony-based differences in foraging distribution lead to increased plastic ingestion in Laysan albatrosses?

    Directory of Open Access Journals (Sweden)

    Lindsay C Young

    Full Text Available When searching for prey, animals should maximize energetic gain, while minimizing energy expenditure by altering their movements relative to prey availability. However, with increasing amounts of marine debris, what once may have been 'optimal' foraging strategies for top marine predators, are leading to sub-optimal diets comprised in large part of plastic. Indeed, the highly vagile Laysan albatross (Phoebastria immutabilis which forages throughout the North Pacific, are well known for their tendency to ingest plastic. Here we examine whether Laysan albatrosses nesting on Kure Atoll and Oahu Island, 2,150 km apart, experience different levels of plastic ingestion. Twenty two geolocators were deployed on breeding adults for up to two years. Regurgitated boluses of undigestable material were also collected from chicks at each site to compare the amount of plastic vs. natural foods. Chicks from Kure Atoll were fed almost ten times the amount of plastic compared to chicks from Oahu despite boluses from both colonies having similar amounts of natural food. Tracking data indicated that adults from either colony did not have core overlapping distributions during the early half of the breeding period and that adults from Kure had a greater overlap with the putative range of the Western Garbage Patch corroborating our observation of higher plastic loads at this colony. At-sea distributions also varied throughout the year suggesting that Laysan albatrosses either adjusted their foraging behavior according to constraints on time away from the nest or to variation in resources. However, in the non-breeding season, distributional overlap was greater indicating that the energy required to reach the foraging grounds was less important than the total energy available. These results demonstrate how a marine predator that is not dispersal limited alters its foraging strategy throughout the reproductive cycle to maximize energetic gain and how this has led to

  6. Effects of supplemental organic cobalt on nutrient digestion and nitrogen balance in lambs fed forage-based diets

    Science.gov (United States)

    The objective of this study was to determine the effects of supplemental organic cobalt on nutrient digestion and nitrogen balance in lambs fed forage-based diets. Sixteen wether lambs (avg initial BW = 28.6 ± 1.3 kg) were used in a 2 × 2 Latin square and randomly allotted to one of two treatments b...

  7. Forage fish interactions: A symposium on creating the tools for ecosystem-based management of marine resources

    DEFF Research Database (Denmark)

    Peck, M.A.; Neuenfeldt, Stefan; Essington, V.M.

    2014-01-01

    Forage fish (FF) have a unique position within marine foodwebs and the development of sustainable harvest strategies for FF will be a critical step in advancing and implementing the broader, ecosystem-based management of marine systems. In all, 70 scientists from 16 nations gathered for a symposium...

  8. Animal based parameters are no panacea for on-farm monitoring of animal welfare

    NARCIS (Netherlands)

    Bracke, M.B.M.

    2007-01-01

    On-farm monitoring of animal welfare is an important, present-day objective in animal welfare science. Scientists tend to focus exclusively on animal-based parameters, possibly because using environment-based parameters could be begging the question why welfare has been affected and because

  9. Supplementation based on protein or energy ingredients to beef cattle consuming low-quality cool-season forages: I. Forage disappearance parameters in rumen-fistulated steers and physiological responses in pregnant heifers.

    Science.gov (United States)

    Cappellozza, B I; Cooke, R F; Guarnieri Filho, T A; Bohnert, D W

    2014-06-01

    Two experiments evaluated the influence of supplement composition on ruminal forage disappearance, performance, and physiological responses of Angus × Hereford cattle consuming a low-quality cool-season forage (8.7% CP and 57% TDN). In Exp. 1, 6 rumen-fistulated steers housed in individual pens were assigned to an incomplete 3 × 2 Latin square design containing 2 periods of 11 d each and the following treatments: 1) supplementation with soybean meal (PROT), 2) supplementation with a mixture of cracked corn, soybean meal, and urea (68:22:10 ratio, DM basis; ENER), or 3) no supplementation (CON). Steers were offered meadow foxtail (Alopecurus pratensis L.) hay for ad libitum consumption. Treatments were provided daily at 0.50 and 0.54% of shrunk BW/steer for PROT and ENER, respectively, to ensure that PROT and ENER intakes were isocaloric and isonitrogenous. No treatment effects were detected on rumen disappearance parameters of forage DM (P ≥ 0.33) and NDF (P ≥ 0.66). In Exp. 2, 35 pregnant heifers were ranked by initial BW on d -7 of the study, allocated into 12 feedlot pens (4 pens/treatment), and assigned to the same treatments and forage intake regimen as in Exp. 1 for 19 d. Treatments were fed once daily at 1.77 and 1.92 kg of DM/heifer for PROT and ENER, respectively, to achieve the same treatment intake as percent of initial BW used in Exp. 1 (0.50 and 0.54% for PROT and ENER, respectively). No treatment effects (P = 0.17) were detected on forage DMI. Total DMI was greater (P forages had similar ruminal forage disappearance and intake, performance, and physiological status if offered supplements based on soybean meal or corn at 0.5% of BW.

  10. Parameter Selection for Ant Colony Algorithm Based on Bacterial Foraging Algorithm

    Directory of Open Access Journals (Sweden)

    Peng Li

    2016-01-01

    Full Text Available The optimal performance of the ant colony algorithm (ACA mainly depends on suitable parameters; therefore, parameter selection for ACA is important. We propose a parameter selection method for ACA based on the bacterial foraging algorithm (BFA, considering the effects of coupling between different parameters. Firstly, parameters for ACA are mapped into a multidimensional space, using a chemotactic operator to ensure that each parameter group approaches the optimal value, speeding up the convergence for each parameter set. Secondly, the operation speed for optimizing the entire parameter set is accelerated using a reproduction operator. Finally, the elimination-dispersal operator is used to strengthen the global optimization of the parameters, which avoids falling into a local optimal solution. In order to validate the effectiveness of this method, the results were compared with those using a genetic algorithm (GA and a particle swarm optimization (PSO, and simulations were conducted using different grid maps for robot path planning. The results indicated that parameter selection for ACA based on BFA was the superior method, able to determine the best parameter combination rapidly, accurately, and effectively.

  11. Free-range pigs foraging on Jerusalem artichokes (Helianthus tuberosus L.) – Effect of feeding strategy on growth, feed conversion and animal behaviour

    DEFF Research Database (Denmark)

    Kongsted, Anne Grete; Horsted, Klaus; Hermansen, John Erik

    2013-01-01

    The nutritional contributions from free-range foraging, growth, feed conversion and behaviour were investigated in 36 growing pigs foraging on Jerusalem artichokes (JA) and fed concentrates restrictedly (30% of energy recommendations) or ad libitum. Compared to the ad libitum fed pigs, the pigs fed...

  12. Optimal Foraging by Birds: Experiments for Secondary & Postsecondary Students

    Science.gov (United States)

    Pecor, Keith W.; Lake, Ellen C.; Wund, Matthew A.

    2015-01-01

    Optimal foraging theory attempts to explain the foraging patterns observed in animals, including their choice of particular food items and foraging locations. We describe three experiments designed to test hypotheses about food choice and foraging habitat preference using bird feeders. These experiments can be used alone or in combination and can…

  13. Enhanced Microgrid Dynamic Performance Using a Modulated Power Filter Based on Enhanced Bacterial Foraging Optimization

    Directory of Open Access Journals (Sweden)

    Ahmed M. Othman

    2017-06-01

    Full Text Available This paper presents a design of microgrid (MG with enhanced dynamic performance. Distributed energy resources (DER are widely used in MGs to match the various load types and profiles. DERs include solar PV cells, wind energy sources, fuel cells, batteries, micro gas-engines and storage elements. MG will include AC/DC circuits, developed power electronics devices, inverters and power electronic controllers. A novel modulated power filters (MPF device will be applied in MG design. Enhanced bacterial foraging optimization (EBFO will be proposed to optimize and set the MPF parameters to enhance and tune the MG dynamic response. Recent dynamic control is applied to minimize the harmonic reference content. EBFO will adapt the gains of MPF dynamic control. The present research achieves an enhancement of MG dynamic performance, in addition to ensuring improvements in the power factor, bus voltage profile and power quality. MG operation will be evaluated by the dynamic response to be fine-tuned by MPF based on EBFO. Digital simulations have validated the results to show the effectiveness and efficient improvement by the proposed strategy.

  14. Adapting Animal-Assisted Therapy Trials to Prison-Based Animal Programs.

    Science.gov (United States)

    Allison, Molly; Ramaswamy, Megha

    2016-09-01

    Prison-based animal programs have shown promise when it comes to increased sociability, responsibility, and levels of patience for inmates who participate in these programs. Yet there remains a dearth of scientific research that demonstrates the impact of prison-based animal programs on inmates' physical and mental health. Trials of animal-assisted therapy interventions, a form of human-animal interaction therapy most often used with populations affected by depression/anxiety, mental illness, and trauma, may provide models of how prison-based animal program research can have widespread implementation in jail and prison settings, whose populations have high rates of mental health problems. This paper reviews the components of prison-based animal programs most commonly practiced in prisons today, presents five animal-assisted therapy case studies, evaluates them based on their adaptability to prison-based animal programs, and discusses the institutional constraints that act as barriers for rigorous prison-based animal program research implementation. This paper can serve to inform the development of a research approach to animal-assisted therapy that nurses and other public health researchers can use in working with correctional populations. © 2016 Wiley Periodicals, Inc.

  15. forage systems mixed with forage legumes grazed by lactating cows

    Directory of Open Access Journals (Sweden)

    Clair Jorge Olivo

    2017-02-01

    Full Text Available Current research evaluates productivity, stocking and nutritional rates of three forage systems with Elephant Grass (EG + Italian Ryegrass (IR + Spontaneous Growth Species (SGS, without forage legumes; EG + IR + SGS + Forage Peanut (FP, mixed with FP; and EG + IR + SGS + Red Clover (RC, mixed with RC, in rotational grazing method by lactating cows. IR developed between rows of EG. FP was maintained, whilst RC was sow to respective forage systems. The experimental design was completely randomized, with three treatments and two replication, subdivided into parcels over time. Mean rate for forage yield and average stocking rate were 10.6, 11.6 and 14.4 t ha-1; 3.0, 2.8 and 3.1 animal unit ha-1 day-1, for the respective systems. Levels of crude protein and total digestible nutrients were 17.8, 18.7 and 17.5%; 66.5, 66.8 and 64.8%, for the respective forage systems. The presence of RC results in better and higher forage yield in the mixture, whilst FP results in greater control of SGS. The inclusion of forage legumes in pasture systems provides better nutritional rates.

  16. Determination of crude protein in animal feed, forage, grain, and oilseeds by using block digestion with a copper catalyst and steam distillation into boric acid: collaborative study.

    Science.gov (United States)

    Thiex, Nancy J; Manson, Harold; Andersson, Shirley; Persson, Jan-Ake

    2002-01-01

    A collaborative study was conducted to evaluate the repeatability and reproducibility of an extension of AOAC Official Method 991.20, Nitrogen (Crude) in Milk, to animal feed, forage (plant tissue), grain, and oilseed materials. Test portions are digested in an aluminum block at 420 degrees C in sulfuric acid with potassium sulfate and a copper catalyst. Digests are cooled and diluted, and concentrated sodium hydroxide is added to neutralize the acid and make the digest basic; the liberated ammonia is distilled by using steam distillation. The liberated ammonia is trapped in a weak boric acid solution and titrated with a stronger standardized acid, hydrochloric acid; colorimetric endpoint detection is used. Fourteen blind samples were sent to 13 collaborators in the United States, Denmark, Sweden, Germany, and the United Kingdom. Recoveries of nitrogen from lysine, tryptophan, and acetanilide were 86.8, 98.8, and 100.1%, respectively. The within-laboratory relative standard deviation (RSDr, repeatability) ranged from 0.40 to 2.38% for crude protein. The among-laboratories (including within-) relative standard deviation (RSD(R), reproducibility) ranged from 0.44 to 2.38%. It is recommended that the method be adopted First Action by AOAC INTERNATIONAL. A lower concentration (1% H3BO3) of trapping solution was compared with the concentration specified in the original protocol (4% H3BO3) and was found comparable for use in an automatic titration system in which titration begins automatically as soon as distillation starts. The Study Directors recommend that 1% H3BO3 as an optional alternative to 4% boric acid trapping solution be allowed for automatic titrators that titrate throughout the distillation.

  17. Produção animal e de forragem em pastagem nativa submetida a distintas ofertas de forragem Animal and forage production on native pasture under different herbage allowance

    Directory of Open Access Journals (Sweden)

    André Brugnara Soares

    2005-10-01

    . This treatment, also, was the only management the animals increased weight at winter. The animal production/ha was smaller in the 16% and 16-12% treatments. The DMA changing over the seasons, as a procedure to manipulate the vegetation structure and composition to increase forage production and average daily weight gain was efficient, and its effect upon the forage and animal production go on all the seasons.

  18. Emergence of Swarming Behavior: Foraging Agents Evolve Collective Motion Based on Signaling

    Science.gov (United States)

    Ikegami, Takashi

    2016-01-01

    Swarming behavior is common in biology, from cell colonies to insect swarms and bird flocks. However, the conditions leading to the emergence of such behavior are still subject to research. Since Reynolds’ boids, many artificial models have reproduced swarming behavior, focusing on details ranging from obstacle avoidance to the introduction of fixed leaders. This paper presents a model of evolved artificial agents, able to develop swarming using only their ability to listen to each other’s signals. The model simulates a population of agents looking for a vital resource they cannot directly detect, in a 3D environment. Instead of a centralized algorithm, each agent is controlled by an artificial neural network, whose weights are encoded in a genotype and adapted by an original asynchronous genetic algorithm. The results demonstrate that agents progressively evolve the ability to use the information exchanged between each other via signaling to establish temporary leader-follower relations. These relations allow agents to form swarming patterns, emerging as a transient behavior that improves the agents’ ability to forage for the resource. Once they have acquired the ability to swarm, the individuals are able to outperform the non-swarmers at finding the resource. The population hence reaches a neutral evolutionary space which leads to a genetic drift of the genotypes. This reductionist approach to signal-based swarming not only contributes to shed light on the minimal conditions for the evolution of a swarming behavior, but also more generally it exemplifies the effect communication can have on optimal search patterns in collective groups of individuals. PMID:27119340

  19. Animal impacts

    Science.gov (United States)

    Norbert V. DeByle

    1985-01-01

    The aspen ecosystem is rich in number and species of animals, especially in comparison to associated coniferous forest types. This natural species diversity and richness has been both increased and influenced by the introduction of domestic livestock. The high value of the aspen type as a forage resource for livestock and as forage and cover for wildlife makes the...

  20. An Improved Bacterial-Foraging Optimization-Based Machine Learning Framework for Predicting the Severity of Somatization Disorder

    Directory of Open Access Journals (Sweden)

    Xinen Lv

    2018-02-01

    Full Text Available It is of great clinical significance to establish an accurate intelligent model to diagnose the somatization disorder of community correctional personnel. In this study, a novel machine learning framework is proposed to predict the severity of somatization disorder in community correction personnel. The core of this framework is to adopt the improved bacterial foraging optimization (IBFO to optimize two key parameters (penalty coefficient and the kernel width of a kernel extreme learning machine (KELM and build an IBFO-based KELM (IBFO-KELM for the diagnosis of somatization disorder patients. The main innovation point of the IBFO-KELM model is the introduction of opposition-based learning strategies in traditional bacteria foraging optimization, which increases the diversity of bacterial species, keeps a uniform distribution of individuals of initial population, and improves the convergence rate of the BFO optimization process as well as the probability of escaping from the local optimal solution. In order to verify the effectiveness of the method proposed in this study, a 10-fold cross-validation method based on data from a symptom self-assessment scale (SCL-90 is used to make comparison among IBFO-KELM, BFO-KELM (model based on the original bacterial foraging optimization model, GA-KELM (model based on genetic algorithm, PSO-KELM (model based on particle swarm optimization algorithm and Grid-KELM (model based on grid search method. The experimental results show that the proposed IBFO-KELM prediction model has better performance than other methods in terms of classification accuracy, Matthews correlation coefficient (MCC, sensitivity and specificity. It can distinguish very well between severe somatization disorder and mild somatization and assist the psychological doctor with clinical diagnosis.

  1. LÍNEA BASE DE ESPECIES ARBÓREAS Y ARBUSTIVAS CON APTITUD FORRAJERA EN SISTEMAS DE PRODUCCIÓN GANADERA DE CLIMA FRÍO DEL DEPARTAMENTO DEL CAUCA AS ESPÉCIES ARBÓREAS E ARBUSTIVAS APTIDÃO COM FORRAGEM DE SISTEMAS DE PRODUÇÃO ANIMAL DO CLIMA FRIO DO DEPARTAMENTO DO CAUCA BASE LINE TREE AND SHUUB SPECIES WITH FORAGE FITNESS LIVESTOCK PRODUCTION SYSTEMS OF THE DEPARTAMENT OF COLD WEATHER CAUCA

    Directory of Open Access Journals (Sweden)

    DENIS A ARBOLEDA

    2011-12-01

    estabelecimento de uma línea base de espécies arbóreas e arbustivas com aptidão forrageira potencialmente utilização em sistemas de produção Bovina para zonas de clima frío departamental, arrojando como resultado uma línea de 17 famílias que na atualidade estão sendo usadas á través de diferentes arranjos nos sistemas pecuários. As pesquisas se desarrolham á partir do reconhecimento e recopilação de informação primaria com ajuda de os produtores da zona, seguida da sistematização e analises para a identificação de aquelas espécies com maior aparição e uso. Si bem se encontro um significativo numero de espécies, é necessário aprofundar o estudo em algumas de estas, dado que a informação respeito á seu desarrolho fenológico e seu comportamento em sistemas pecuários é desconhecido hasta agora.Given the low production of high quality fodder and environmental issues related to livestock at the regional level, this paper presents the results of research conducted in livestock production systems of tropical high Cauca Department, among the municipalities Silvia, Totoro, Sotara and Purace. The study aimed to establish a baseline of tree and shrub species with fitness forage utilization in beef production systems for cold climates department, dropping a line resulted in 17 families are currently being used by different arrangements livestock. La research systems developed from the recognition and primary data collection with the help of local producers, followed by the systematization and analysis for the identification of those species with higher occurrence and use. Although there were a significant number of species, further study is necessary in some of these, since information about their phenological development and behavior in cattle production systems is still unknown. Thus, the findings constitute a source of information for the design of livestock production systems more efficient in cold climates, while the basis for the formulation of future

  2. Risk-based testing of imported animals

    NARCIS (Netherlands)

    Vos-de Jong, de Clazien; Goot, van der J.A.; Zijderveld, van F.G.; Swanenburg, M.; Elbers, A.R.W.

    2015-01-01

    In intra-EU trade, the health status of animals is warranted by issuing a health certificate after clinical inspection in the exporting country. This certificate cannot provide guarantee of absence of infection, especially not for diseases with a long incubation period and no overt clinical signs

  3. Sympatric cattle grazing and desert bighorn sheep foraging

    Science.gov (United States)

    Garrison, Kyle R.; Cain, James W.; Rominger, Eric M.; Goldstein, Elise J.

    2015-01-01

    Foraging behavior affects animal fitness and is largely dictated by the resources available to an animal. Understanding factors that affect forage resources is important for conservation and management of wildlife. Cattle sympatry is proposed to limit desert bighorn population performance, but few studies have quantified the effect of cattle foraging on bighorn forage resources or foraging behavior by desert bighorn. We estimated forage biomass for desert bighorn sheep in 2 mountain ranges: the cattle-grazed Caballo Mountains and the ungrazed San Andres Mountains, New Mexico. We recorded foraging bout efficiency of adult females by recording feeding time/step while foraging, and activity budgets of 3 age-sex classes (i.e., adult males, adult females, yearlings). We also estimated forage biomass at sites where bighorn were observed foraging. We expected lower forage biomass in the cattle-grazed Caballo range than in the ungrazed San Andres range and lower biomass at cattle-accessible versus inaccessible areas within the Caballo range. We predicted bighorn would be less efficient foragers in the Caballo range. Groundcover forage biomass was low in both ranges throughout the study (Jun 2012–Nov 2013). Browse biomass, however, was 4.7 times lower in the Caballo range versus the San Andres range. Bighorn in the Caballo range exhibited greater overall daily travel time, presumably to locate areas of higher forage abundance. By selecting areas with greater forage abundance, adult females in the Caballo range exhibited foraging bout efficiency similar to their San Andres counterparts but lower overall daily browsing time. We did not find a significant reduction in forage biomass at cattle-accessible areas in the Caballo range. Only the most rugged areas in the Caballo range had abundant forage, potentially a result of intensive historical livestock use in less rugged areas. Forage conditions in the Caballo range apparently force bighorn to increase foraging effort by

  4. Spatial memory in foraging games.

    Science.gov (United States)

    Kerster, Bryan E; Rhodes, Theo; Kello, Christopher T

    2016-03-01

    Foraging and foraging-like processes are found in spatial navigation, memory, visual search, and many other search functions in human cognition and behavior. Foraging is commonly theorized using either random or correlated movements based on Lévy walks, or a series of decisions to remain or leave proximal areas known as "patches". Neither class of model makes use of spatial memory, but search performance may be enhanced when information about searched and unsearched locations is encoded. A video game was developed to test the role of human spatial memory in a canonical foraging task. Analyses of search trajectories from over 2000 human players yielded evidence that foraging movements were inherently clustered, and that clustering was facilitated by spatial memory cues and influenced by memory for spatial locations of targets found. A simple foraging model is presented in which spatial memory is used to integrate aspects of Lévy-based and patch-based foraging theories to perform a kind of area-restricted search, and thereby enhance performance as search unfolds. Using only two free parameters, the model accounts for a variety of findings that individually support competing theories, but together they argue for the integration of spatial memory into theories of foraging. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. FORAGES AND PASTURES SYMPOSIUM: Improving efficiency of production in pasture- and range-based beef and dairy systems.

    Science.gov (United States)

    Mulliniks, J T; Rius, A G; Edwards, M A; Edwards, S R; Hobbs, J D; Nave, R L G

    2015-06-01

    Despite overall increased production in the last century, it is critical that grazing production systems focus on improving beef and dairy efficiency to meet current and future global food demands. For livestock producers, production efficiency is essential to maintain long-term profitability and sustainability. This continued viability of production systems using pasture- and range-based grazing systems requires more rapid adoption of innovative management practices and selection tools that increase profitability by optimizing grazing management and increasing reproductive performance. Understanding the genetic variation in cow herds will provide the ability to select cows that require less energy for maintenance, which can potentially reduce total energy utilization or energy required for production, consequently improving production efficiency and profitability. In the United States, pasture- and range-based grazing systems vary tremendously across various unique environments that differ in climate, topography, and forage production. This variation in environmental conditions contributes to the challenges of developing or targeting specific genetic components and grazing systems that lead to increased production efficiency. However, across these various environments and grazing management systems, grazable forage remains the least expensive nutrient source to maintain productivity of the cow herd. Beef and dairy cattle can capitalize on their ability to utilize these feed resources that are not usable for other production industries. Therefore, lower-cost alternatives to feeding harvested and stored feedstuffs have the opportunity to provide to livestock producers a sustainable and efficient forage production system. However, increasing production efficiency within a given production environment would vary according to genetic potential (i.e., growth and milk potential), how that genetic potential fits the respective production environment, and how the grazing

  6. Canopy characteristics, animal behavior and forage intake by goats grazing on Tanzania-grass pasture with different heights - doi: 10.4025/actascianimsci.v34i4.14544

    Directory of Open Access Journals (Sweden)

    Maurílio Souza dos Santos

    2012-10-01

    Full Text Available This study evaluated the influence of Tanzania-grass sward height (30, 50, 70 and 90 cm on the morphological characteristics of the canopy, grazing behavior and forage intake by adult Anglo Nubian female goats. A completely randomized experimental design was employed, with two replicates in space and two replicates in time. Six animals were used to assess the grazing behavior, and four, the ingestion process. The rise in sward height increased the forage and leaf mass, the percentages of stem and dead material, and reduced the leaf stem-1 ratio. Above 50 cm there was an increase in grazing time and a decrease in leisure time. A positive linear correlation was detected between sward height and bite depth. The consumed forage mass, ingestion rate and daily intake were higher at 50 cm, indicating that the other heights reduced the intake process. The sward height was negatively correlated to the bite rate and positively to the bite time. The sward height of 50 cm presents the best combination of features, favoring the grazing and ingestive behavior of female adult goats.

  7. Introductory animal science-based instruction influences attitudes on animal agriculture issues.

    Science.gov (United States)

    Bobeck, E A; Combs, D K; Cook, M E

    2014-02-01

    The demographics of incoming university animal science majors have shifted from students with a farm background to urban students with no history of direct livestock contact. Research completed before the Internet was a central source of information indicated that incoming urban students tend to express no opinion or a neutral opinion regarding livestock agriculture issues. Due to the changing background of incoming students enrolled in introductory university-level animal science classes, we sought to determine 1) if livestock background (self-identified as raised in a farm or urban setting), sex, or animal science career interest influenced the opinions of incoming students regarding critical issues involving livestock farming practices and 2) if 15 wk of introductory animal science instruction changed student opinions. A total of 224 students were given 2 identical anonymous surveys (start and end of 15 wk) with 5 demographic questions and 9 animal issue statements. For each statement, students marked their opinion by placing a vertical line on a continuous 130 mm horizontal line, where a vertical line placed at 0 mm = strongly agree and 130 mm = strongly disagree. Data were analyzed by ANOVA to determine any significant effects of instruction, background, sex, and future career preference on survey responses. Before instruction, urban students were less agreeable than farm students that animal farming was moral and humane and that farmers are concerned about animal welfare and livestock are of value to society (P ≤ 0.05). Urban students were more likely than farm students to purchase organic foods or food based on environmental/welfare standards (P ≤ 0.05). Introductory animal science instruction resulted in students becoming more agreeable that animal farming was humane, farmers are concerned about animal welfare, and animal agriculture is a value to society (P ≤ 0.05). Postinstruction, students were more likely to buy food products based on price (P

  8. Systematic review of the influence of foraging habitat on red-cockaded woodpecker reproductive success.

    Energy Technology Data Exchange (ETDEWEB)

    Garabedian, James E. [North Carolina State University

    2014-04-01

    Relationships between foraging habitat and reproductive success provide compelling evidence of the contribution of specific vegetative features to foraging habitat quality, a potentially limiting factor for many animal populations. For example, foraging habitat quality likely will gain importance in the recovery of the threatened red-cockaded woodpecker Picoides borealis (RCW) in the USA as immediate nesting constraints are mitigated. Several researchers have characterized resource selection by foraging RCWs, but emerging research linking reproductive success (e.g. clutch size, nestling and fledgling production, and group size) and foraging habitat features has yet to be synthesized. Therefore, we reviewed peer-refereed scientific literature and technical resources (e.g. books, symposia proceedings, and technical reports) that examined RCW foraging ecology, foraging habitat, or demography to evaluate evidence for effects of the key foraging habitat features described in the species’ recovery plan on group reproductive success. Fitness-based habitat models suggest foraging habitat with low to intermediate pine Pinus spp. densities, presence of large and old pines, minimal midstory development, and herbaceous groundcover support more productive RCW groups. However, the relationships between some foraging habitat features and RCW reproductive success are not well supported by empirical data. In addition, few regression models account for > 30% of variation in reproductive success, and unstandardized multiple and simple linear regression coefficient estimates typically range from -0.100 to 0.100, suggesting ancillary variables and perhaps indirect mechanisms influence reproductive success. These findings suggest additional research is needed to address uncertainty in relationships between foraging habitat features and RCW reproductive success and in the mechanisms underlying those relationships.

  9. Animals

    International Nuclear Information System (INIS)

    Skuterud, L.; Strand, P.; Howard, B.J.

    1997-01-01

    The radionuclides of most concern with respect to contamination of animals after a nuclear accident are radioiodine, radiocaesium and radiostrontium (ICRP 30, 1979). Of the other significant anthropogenic radionuclides likely to be released in most accidents, only small proportions of that ingested will be absorbed in an animals gut, and the main animal products, milk and meat, will not normally be contaminated to a significant extent. Animal products will mostly be contaminated as a result of ingestion of contaminated feed and possibly, but to a much lesser extent, from inhalation (for radioiodine only). Direct external contamination of animals is of little or no consequence in human food production. Radioiodine and radiostrontium are important with respect to contamination of milk; radiocaesium contaminates both milk and meat. The physical and chemical form of a radionuclide can influence its absorption in the animal gut. For example, following the Chernobyl accident radiocaesium incorporated into vegetation by root uptake was more readily absorbed than that associated with the original deposit. The transfer of radiocaesium and radiostrontium to animals will be presented both as transfer coefficients and aggregated transfer coefficients. For most animal meat products, only radiocaesium is important as other radionuclides do not significantly contaminate muscle. Farm animal products are the most important foodstuff determining radiocaesium intake by the average consumer in the Nordic countries. The major potential source of radioiodine and radiostrontium to humans is milk and milk products. Of the different species, the smaller animals have the highest transfer of radiocaesium from fodder to meat and milk. (EG)

  10. Developing Educational Computer Animation Based on Human Personality Types

    Science.gov (United States)

    Musa, Sajid; Ziatdinov, Rushan; Sozcu, Omer Faruk; Griffiths, Carol

    2015-01-01

    Computer animation in the past decade has become one of the most noticeable features of technology-based learning environments. By its definition, it refers to simulated motion pictures showing movement of drawn objects, and is often defined as the art in movement. Its educational application known as educational computer animation is considered…

  11. Investigating User Experiences Through Animation-based Sketching

    DEFF Research Database (Denmark)

    Vistisen, Peter; Poulsen, Søren Bolvig

    2016-01-01

    motion graphics and animation to sketch design ideas into diegetic design solutions. Through a deep-dive into two cases studies we discuss how animation-based sketching techniques supported the investigation of user experience aspects in design scenarios, and whether the expression is dependent...

  12. Data analysis using a data base driven graphics animation system

    International Nuclear Information System (INIS)

    Schwieder, D.H.; Stewart, H.D.; Curtis, J.N.

    1985-01-01

    A graphics animation system has been developed at the Idaho National Engineering Laboratory (INEL) to assist engineers in the analysis of large amounts of time series data. Most prior attempts at computer animation of data involve the development of large and expensive problem-specific systems. This paper discusses a generalized interactive computer animation system designed to be used in a wide variety of data analysis applications. By using relational data base storage of graphics and control information, considerable flexibility in design and development of animated displays is achieved

  13. Animals

    Energy Technology Data Exchange (ETDEWEB)

    Skuterud, L.; Strand, P. [Norwegian Radiation Protection Authority (Norway); Howard, B.J. [Inst. of Terrestrial Ecology (United Kingdom)

    1997-10-01

    The radionuclides of most concern with respect to contamination of animals after a nuclear accident are radioiodine, radiocaesium and radiostrontium (ICRP 30, 1979). Of the other significant anthropogenic radionuclides likely to be released in most accidents, only small proportions of that ingested will be absorbed in an animals gut, and the main animal products, milk and meat, will not normally be contaminated to a significant extent. Animal products will mostly be contaminated as a result of ingestion of contaminated feed and possibly, but to a much lesser extent, from inhalation (for radioiodine only). Direct external contamination of animals is of little or no consequence in human food production. Radioiodine and radiostrontium are important with respect to contamination of milk; radiocaesium contaminates both milk and meat. The physical and chemical form of a radionuclide can influence its absorption in the animal gut. For example, following the Chernobyl accident radiocaesium incorporated into vegetation by root uptake was more readily absorbed than that associated with the original deposit. The transfer of radiocaesium and radiostrontium to animals will be presented both as transfer coefficients and aggregated transfer coefficients. For most animal meat products, only radiocaesium is important as other radionuclides do not significantly contaminate muscle. Farm animal products are the most important foodstuff determining radiocaesium intake by the average consumer in the Nordic countries. The major potential source of radioiodine and radiostrontium to humans is milk and milk products. Of the different species, the smaller animals have the highest transfer of radiocaesium from fodder to meat and milk. (EG). 68 refs.

  14. Representing the acquisition and use of energy by individuals in agent-based models of animal populations

    DEFF Research Database (Denmark)

    Sibly, RS; Grimm, Volker; Johnston, Alice S.A.

    2013-01-01

    Agent-based models (ABMs) are widely used to predict how populations respond to changing environments. As the availability of food varies in space and time, individuals should have their own energy budgets, but there is no consensus as to how these should be modelled. Here, we use knowledge...... of physiological ecology to identify major issues confronting the modeller and to make recommendations about how energy budgets for use in ABMs should be constructed. Our proposal is that modelled animals forage as necessary to supply their energy needs for maintenance, growth and reproduction....... If there is sufficient energy intake, an animal allocates the energy obtained in the order: maintenance, growth, reproduction, energy storage, until its energy stores reach an optimal level. If there is a shortfall, the priorities for maintenance and growth/reproduction remain the same until reserves fall to a critical...

  15. Corn in consortium with forages

    OpenAIRE

    Cássia Maria de Paula Garcia; Marcelo Andreotti; Marcelo Carvalho Minhoto Teixeira Filho; Keny Samejima Mascarenha Lopes; Ciniro Costa; Erikelly Aline Ribeiro de Santana

    2013-01-01

    The basic premises for sustainable agricultural development with focus on rural producers are reducing the costs of production and aggregation of values through the use crop-livestock system (CLS) throughout the year. The CLS is based on the consortium of grain crops, especially corn with tropical forages, mainly of the genus Panicum and Urochloa. The study aimed to evaluate the grain yield of irrigated corn crop intercropped with forage of the genus Panicum and Urochloa. The experiment was c...

  16. Sensory-based conservation of seabirds: a review of management strategies and animal behaviours that facilitate success.

    Science.gov (United States)

    Friesen, Megan R; Beggs, Jacqueline R; Gaskett, Anne C

    2017-08-01

    Sensory-based conservation harnesses species' natural communication and signalling behaviours to mitigate threats to wild populations. To evaluate this emerging field, we assess how sensory-based manipulations, sensory mode, and target taxa affect success. To facilitate broader, cross-species application of successful techniques, we test which behavioural and life-history traits correlate with positive conservation outcomes. We focus on seabirds, one of the world's most rapidly declining groups, whose philopatry, activity patterns, foraging, mate choice, and parental care behaviours all involve reliance on, and therefore strong selection for, sophisticated sensory physiology and accurate assessment of intra- and inter-species signals and cues in several sensory modes. We review the use of auditory, olfactory, and visual methods, especially for attracting seabirds to newly restored habitat or deterring birds from fishing boats and equipment. We found that more sensory-based conservation has been attempted with Procellariiformes (tube-nosed seabirds) and Charadriiformes (e.g. terns and gulls) than other orders, and that successful outcomes are more likely for Procellariiformes. Evolutionary and behavioural traits are likely to facilitate sensory-based techniques, such as social attraction to suitable habitat, across seabird species. More broadly, successful application of sensory-based conservation to other at-risk animal groups is likely to be associated with these behavioural and life-history traits: coloniality, philopatry, nocturnal, migratory, long-distance foraging, parental care, and pair bonds/monogamy. © 2016 Cambridge Philosophical Society.

  17. Produção de forragem e produção animal em pastagem com duas disponibilidades de forragem associadas ou não à suplementação energética Effects of forage availability and energy supplementation on herbage accumulation rate and animal yield

    Directory of Open Access Journals (Sweden)

    Alcides Pilau

    2005-08-01

    Full Text Available Neste experimento, avaliou-se o efeito de duas disponibilidades de forragem, 1.200 e 1.500 kg/ha de matéria seca (MS, e do uso de suplementação energética sobre a produção de forragem e a produção animal em pastagem de aveia (Avena strigosa Schreb + azevém (Lolium multiflorum Lam. Foram utilizadas 90 novilhas da raça Charolês e suas cruzas com Nelore, com peso vivo (PV de 164 kg no início do pastejo, submetidas às seguintes combinações: DFB - disponibilidade de forragem baixa; DFA - disponibilidade de forragem alta; DFBS - disponibilidade de forragem baixa + suplementação energética; DFAS - disponibilidade de forragem alta + suplementação energética. O suplemento fornecido foi grão de sorgo moído, na proporção de 0,7% do PV. As variáveis estudadas foram produção de forragem (PF, carga animal (CA e ganho de peso vivo por área (GPA. A PF não foi influenciada pelo manejo da pastagem e pela suplementação aos animais. O acúmulo de forragem diário estimado foi de 45,53 kg/ha de MS. A CA na DFA, média de 862 kg/ha de PV, apresentou pouca variação no decorrer do ciclo de pastejo. Em DFAS, DFB e DFBS, a carga animal foi extremamente variável e, a partir de 26/08, foi maior na DFBS. A utilização de 1.200 kg/ha de MS não afetou o GPA, enquanto a suplementação aos animais proporcionou aumento de 59,4% em relação ao uso exclusivo da pastagem.The trial was conducted to evaluate two forage availabilities (1.200 and 1.500 kg/ha of dry matter [DM] and energy supplementation of winter pasture on herbage and animal yields. The pasture was a mixture of oat (Avena strigosa Schreb + Italian ryegrass (Lolium multiflorum Lam. Ninety Charolais and Charolais crossbred Nellore heifers, with initial live weight of 164 kg, were submitted to the following treatments: LFA - low forage availability; HFA - high forage availability; LFAS - low forage availability + supplementation; HFAS - high forage availability + supplementation

  18. Combustion of animal or vegetable based liquid waste products

    International Nuclear Information System (INIS)

    Wikman, Karin; Berg, Magnus

    2002-04-01

    In this project experiences from combustion of animal and vegetable based liquid waste products have been compiled. Legal aspects have also been taken into consideration and the potential for this type of fuel on the Swedish energy market has been evaluated. Today the supply of animal and vegetable based liquid waste products for energy production in Sweden is limited. The total production of animal based liquid fat is about 10,000 tonnes annually. The animal based liquid waste products origin mainly from the manufacturing of meat and bone meal. Since meat and bone meal has been banned from use in animal feeds it is possible that the amount of animal based liquid fat will decrease. The vegetable based liquid waste products that are produced in the processing of vegetable fats are today used mainly for internal energy production. This result in limited availability on the commercial market. The potential for import of animal and vegetable based liquid waste products is estimated to be relatively large since the production of this type of waste products is larger in many other countries compared to Sweden. Vegetable oils that are used as food or raw material in industries could also be imported for combustion, but this is not reasonable today since the energy prices are relatively low. Restrictions allow import of SRM exclusively from Denmark. This is today the only limit for increased imports of animal based liquid fat. The restrictions for handle and combustion of animal and vegetable based liquid waste products are partly unclear since this is covered in several regulations that are not easy to interpret. The new directive for combustion of waste (2000/76/EG) is valid for animal based waste products but not for cadaver or vegetable based waste products from provisions industries. This study has shown that more than 27,400 tonnes of animal based liquid waste products and about 6,000 tonnes of vegetable based liquid waste products were used for combustion in Sweden

  19. Effect of forage supplementation and alkali treatment of cocoa pod on the utilization of cocoa pod based diets by ruminants

    International Nuclear Information System (INIS)

    Smith, O.B.

    1987-01-01

    Two treatment methods - forage supplementation and chemical treatment - both potentially capable of improving cocoa pod utilization by ruminants were evaluated. Forage supplementation, using Gliricidia sepium of cattle fed a 50% cocoa pod diet yielded no positive results. Consumption of Gliricidia was poor and equalled only 0.2 kg/head/d. Feed intake (4.6 versus 4.8 kg dry matter (DM)/d), growth rate (0.37 versus 0.40 kg/d) and feed/gain (12.7 versus 12.0) for control and test cattle were similar (P>0.05). Chemical treatment using cocoa pod ash solutions (PAS) - a caustic material - was more successful. Rumen digestibility (as determined by the nylon bag technique) of cocoa pods treated with PAS, equivalent in alkalinity to 2 (P 2 ), 4 (P 4 ), 6 (P 6 ) and 8% (P 8 ) NaOH, was linearly improved (P 0.05). Dry matter, ADF and NDF degradabilities increased (P 6 and 55, 46 and 42%, respectively, for P 8 treated samples. Dry matter digestibilities of cocoa pod based diets also increased (P 8 treated) in sheep and to 60% in goats. Nevertheless, treatment with P 8 solutions reduced (P 0.75 in sheep and from 48 to 42 g DM/kg W 0.75 in goats. Feed intake, however, was normal for diets containing P 6 treated cocoa pods (67 and 61 g DM/kg W 0.75 ) for sheep and goats, respectively. Cocoa pod ash for treating cocoa pods should therefore not be stronger than the P 6 level which corresponds in alkalinity to 6% NaOH. (author)

  20. UAV based mapping of variation in grassland yield for forage production in Arctic environments

    Science.gov (United States)

    Davids, C.; Karlsen, S. R.; Jørgensen, M.; Ancin Murguzur, F. J.

    2017-12-01

    Grassland cultivation for animal feed is the key agricultural activity in northern Norway. Even though the growing season has increased by at least a week in the last 30 years, grassland yields appear to have declined, probably due to more challenging winter conditions and changing agronomy practices. The ability for local and regional crop productivity forecasting would assist farmers with management decisions and would provide local and national authorities with a better overview over productivity and potential problems due to e.g. winter damage. Remote sensing technology has long been used to estimate and map the variability of various biophysical parameters, but calibration is important. In order to establish the relationship between spectral reflectance and grass yield in northern European environments we combine Sentinel-2 time series, UAV-based multispectral measurements, and ground-based spectroradiometry, with biomass analyses and observations of species composition. In this presentation we will focus on the results from the UAV data acquisition. We used a multirotor UAV with different sensors (a multispectral Rikola camera, and NDVI and RGB cameras) to image a number of cultivated grasslands of different age and productivity in northern Norway in June/July 2016 and 2017. Following UAV data acquisition, 10 to 20 in situ measurements were made per field using a FieldSpec3 (350-2500 nm). In addition, samples were taken to determine biomass and grass species composition. The imaging and sampling was done immediately prior to harvesting. The Rikola camera, when used as a stand-alone camera mounted on a UAV, can collect 15 bands with a spectral width of 10-15 nm in the range between 500-890 nm. In the initial analysis of the 2016 data we investigated how well different vegetation indices correlated with biomass and showed that vegetation indices that include red edge bands perform better than widely used indices such as NDVI. We will extend the analysis with

  1. Produtividade de sistemas forrageiros consorciados com amendoim forrageiro ou trevo vermelho Productivity of pastures-based systems mixed to forage peanut or red clover

    Directory of Open Access Journals (Sweden)

    Ricardo Lima de Azevedo Junior

    2012-11-01

    Full Text Available O objetivo desta pesquisa foi avaliar três sistemas forrageiros (SF com capim elefante (CE Pennisetum purpureum Schum., cv. 'MerckeronPinda' + espécies de crescimento espontâneo (ECE + azevém anual (AZ Lolium multiflorum Lam., cv. 'Comum', como SF1; CE + ECE + AZ + amendoim forrageiro (AF Arachis pintoi Krap. e Greg., cv. 'Amarillo', como SF2; e CE + ECE + AZ + trevo vermelho (TV Trifolium pratense L., cv. 'Estanzoela 116', como SF3. O CE foi estabelecido em linhas afastadas a cada 4m. O azevém anual foi estabelecido entre as linhas do CE durante o período hibernal; o TV foi semeado e o AF foi preservado nos respectivos tratamentos. Para avaliação, foram usadas vacas da raça Holandesa que receberam 5,5kg dia-1 como complemento alimentar. Foram avaliadas a taxa de acúmulo diário de matéria seca (TA, a massa de forragem desaparecida (MFD, a matéria seca desaparecida com base em 100kg de peso vivo (MSD e a produção de forragem (PF, as composições botânica e estrutural do CE. O delineamento experimental foi o inteiramente casualizado, com três tratamentos (SF e duas repetições (piquetes em parcelas subdivididas no tempo (pastejo. Durante o período experimental (341 dias, foram efetuados nove ciclos de pastejo. Os valores médios de TA, MFD, MSD e PF foram de 53,16kg ha-1; 36,13%; 2,77kg de matéria seca por 100kg de peso vivo e 17,80t ha-1. Para a variável ECE, houve aumento significativo no SF1. Considerando a carga animal, o SF3 apresentou melhor desempenho.The objective of this research was to evaluate of tree pasture-based systems (PS with elephantgrass (EG Pennisetum purpureum Schum., cv. 'Merckeron Pinda' + spontaneous growing species (SGS, annual ryegrass (RG Lolium multiflorum Lam., cv. 'Comum', for PS1; EG + SGS + forage peanut (FP Arachis pintoi Krap. e Greg., cv. 'Amarillo', for PS2; and EG + SGS + RG + red clover (RC Trifolium pratense L., cv. 'Estanzoela 116', for PS3. EG was planted in lines with a distance of 4m

  2. Rich pickings near large communal roosts favor 'gang' foraging by juvenile common ravens, Corvus corax.

    Directory of Open Access Journals (Sweden)

    Sasha R X Dall

    Full Text Available Ravens (Corvus corax feed primarily on rich but ephemeral carcasses of large animals, which are usually defended by territorial pairs of adults. Non-breeding juveniles forage socially and aggregate in communal winter roosts, and these appear to function as 'information centers' regarding the location of the rare food bonanzas: individuals search independently of one another and pool their effort by recruiting each other at roosts. However, at a large raven roost in Newborough on Anglesey, North Wales, some juveniles have been observed recently to forage in 'gangs' and to roost separately from other birds. Here we adapt a general model of juvenile common raven foraging behavior where, in addition to the typical co-operative foraging strategy, such gang foraging behavior could be evolutionarily stable near winter raven roosts. We refocus the model on the conditions under which this newly documented, yet theoretically anticipated, gang-based foraging has been observed. In the process, we show formally how the trade off between search efficiency and social opportunity can account for the existence of the alternative social foraging tactics that have been observed in this species. This work serves to highlight a number of fruitful avenues for future research, both from a theoretical and empirical perspective.

  3. Precise MRI-based stereotaxic surgery in large animal models

    DEFF Research Database (Denmark)

    Glud, A. N.; Bech, J.; Tvilling, L.

    and subcortical anatomical differences. NEW METHOD: We present a convenient method to make an MRI-visible skull fiducial for 3D MRI-based stereotaxic procedures in larger experimental animals. Plastic screws were filled with either copper-sulphate solution or MRI-visible paste from a commercially available......BACKGROUND: Stereotaxic neurosurgery in large animals is used widely in different sophisticated models, where precision is becoming more crucial as desired anatomical target regions are becoming smaller. Individually calculated coordinates are necessary in large animal models with cortical...... cranial head marker. The screw fiducials were inserted in the animal skulls and T1 weighted MRI was performed allowing identification of the inserted skull marker. RESULTS: Both types of fiducial markers were clearly visible on the MRÍs. This allows high precision in the stereotaxic space. COMPARISON...

  4. LivestockPlus — The sustainable intensification of forage-based agricultural systems to improve livelihoods and ecosystem services in the tropics

    Directory of Open Access Journals (Sweden)

    I. Rao

    2015-05-01

    Full Text Available As global demand for livestock products (such as meat, milk and eggs is expected to double by 2050, necessary increases to future production must be reconciled with negative environmental impacts that livestock cause. This paper describes the LivestockPlus concept and demonstrates how the sowing of improved forages can lead to the sustainable intensification of mixed crop-forage-livestock-tree systems in the tropics by producing multiple social, economic and environmental benefits. Sustainable intensification not only improves the productivity of tropical forage-based systems but also reduces the ecological footprint of livestock production and generates a diversity of ecosystem services (ES such as improved soil quality and reduced erosion, sedimentation and greenhouse gas (GHG emissions. Integrating improved grass and legume forages into mixed production systems (crop-livestock, tree-livestock, crop-tree-livestock can restore degraded lands and enhance system resilience to drought and waterlogging associated with climate change. When properly managed tropical forages accumulate large amounts of carbon in soil, fix atmospheric nitrogen (legumes, inhibit nitrification in soil and reduce nitrous oxide emissions (grasses, and reduce GHG emissions per unit livestock product. The LivestockPlus concept is defined as the sustainable intensification of forage-based systems, which is based on 3 interrelated intensification processes: genetic intensification - the development and use of superior grass and legume cultivars for increased livestock productivity; ecological intensification - the development and application of improved farm and natural resource management practices; and socio-economic intensification - the improvement of local and national institutions and policies, which enable refinements of technologies and support their enduring use. Increases in livestock productivity will require coordinated efforts to develop supportive government, non

  5. Cooperative Optimization QoS Cloud Routing Protocol Based on Bacterial Opportunistic Foraging and Chemotaxis Perception for Mobile Internet

    Directory of Open Access Journals (Sweden)

    Shujuan Wang

    2015-01-01

    Full Text Available In order to strengthen the mobile Internet mobility management and cloud platform resources utilization, optimizing the cloud routing efficiency is established, based on opportunistic bacterial foraging bionics, and puts forward a chemotaxis perception of collaborative optimization QoS (Quality of Services cloud routing mechanism. The cloud routing mechanism is based on bacterial opportunity to feed and bacterial motility and to establish the data transmission and forwarding of the bacterial population behavior characteristics. This mechanism is based on the characteristics of drug resistance of bacteria and the structure of the field, and through many iterations of the individual behavior and population behavior the bacteria can be spread to the food gathering area with a certain probability. Finally, QoS cloud routing path would be selected and optimized based on bacterial bionic optimization and hedge mapping relationship between mobile Internet node and bacterial population evolution iterations. Experimental results show that, compared with the standard dynamic routing schemes, the proposed scheme has shorter transmission delay, lower packet error ratio, QoS cloud routing loading, and QoS cloud route request overhead.

  6. Discovery based and targeted Mass Spectrometry in farm animal proteomics

    DEFF Research Database (Denmark)

    Bendixen, Emøke

    2013-01-01

    for investigating farm animal biology. SRM is particularly important for validation biomarker candidates This talk will introduce the use of different mass spectrometry approaches through examples related to food quality and animal welfare, including studies of gut health in pigs, host pathogen interactions......Technological advances in mass spectrometry have greatly improved accuracy and speed of analyses of proteins and biochemical pathways. These proteome technologies have transformed research and diagnostic methods in the biomedical fields, and in food and farm animal sciences proteomics can be used...... be monitored to improve welfare in large industrial settings of current livestock industry. The combination of discovery based LC-MS/MS methods and the more hypothesis-based targeted mass spectrometry method commonly referred to as selected reaction monitoring or SRM, provide a powerful approach...

  7. Determining spatio-temporal distribution of bee forage species of Al-Baha region based on ground inventorying supported with GIS applications and Remote Sensed Satellite Image analysis

    Directory of Open Access Journals (Sweden)

    Nuru Adgaba

    2017-07-01

    Full Text Available In arid zones, the shortage of bee forage is critical and usually compels beekeepers to move their colonies in search of better forages. Identifying and mapping the spatiotemporal distribution of the bee forages over given area is important for better management of bee colonies. In this study honey bee plants in the target areas were inventoried following, ground inventory work supported with GIS applications. The study was conducted on 85 large plots of 50 × 50 m each. At each plot, data on species name, height, base diameter, crown height, crown diameter has been taken for each plant with their respective geographical positions. The data were stored, and processed using Trimble GPS supported with ArcGIS10 software program. The data were used to estimate the relative frequency, density, abundance and species diversity, species important value index and apicultural value of the species. In addition, Remotely Sensed Satellite Image of the area was obtained and processed using Hopfield Artificial Neural Network techniques. During the study, 182 species from 49 plant families were identified as bee forages of the target area. From the total number of species; shrubs, herbs and trees were accounting for 61%, 27.67%, and 11.53% respectively. Of which Ziziphus spina-christi, Acacia tortilis, Acacia origina, Acacia asak, Lavandula dentata, and Hypoestes forskaolii were the major nectar source plants of the area in their degree of importance. The average vegetation cover values of the study areas were low (<30% with low Shannon’s species diversity indices (H′ of 0.5–1.52 for different sites. Based on the eco-climatological factors and the variations in their flowering period, these major bee forage species were found to form eight distinct spatiotemporal categories which allow beekeepers to migrate their colonies to exploit the resources at different seasons and place. The Remote Sensed Satellite Image analysis confirmed the spatial

  8. High-concentrate diets based on forages harvested at different maturity stages affect ruminal synthesis of B vitamins in lactating dairy cows.

    Science.gov (United States)

    Castagnino, D S; Kammes, K L; Allen, M S; Gervais, R; Chouinard, P Y; Girard, C L

    2017-04-01

    Effects of plant maturity on apparent ruminal synthesis and post-ruminal supply of B vitamins were evaluated in two feeding trials. Diets containing alfalfa (Trial 1) or orchardgrass (Trial 2) silages harvested either (1) early cut, less mature (EC) or (2) late cut, more mature (LC) as the sole forage were offered to ruminally and duodenally cannulated lactating Holstein cows in crossover design experiments. In Trial 1, conducted with 16 cows (569±43 kg of empty BW (ruminal content removed) and 43.7±8.6 kg/day of 3.5% fat-corrected milk yield; mean±SD) in two 17-day treatment periods, both diets provided ~22% forage NDF and 27% total NDF, and the forage-to-concentrate ratios were 53 : 47 and 42 : 58 for EC and LC, respectively. In Trial 2, conducted with 13 cows (588±55 kg of empty BW and 43.7±7.7 kg/day of 3.5% fat-corrected milk yield; mean±SD) in two 18-day treatment periods, both diets provided ~25% forage NDF and 31% total NDF; the forage-to-concentrate ratios were 58 : 42 and 46 : 54 for EC and LC, respectively. Thiamin, riboflavin, niacin, vitamin B6, folates and vitamin B12 were measured in feed and duodenal content. Apparent ruminal synthesis was calculated as the duodenal flow minus the intake. Diets based on EC alfalfa decreased the amounts of thiamin, niacin and folates reaching the duodenum, whereas diets based on EC orchardgrass increased riboflavin duodenal flow. Daily apparent ruminal synthesis of thiamin, riboflavin, niacin and vitamin B6 were correlated negatively with their intake, suggesting a microbial regulation of their concentration in the rumen. Vitamin B12 apparent ruminal synthesis was correlated negatively with total volatile fatty acids concentration, but positively with ruminal pH and microbial N duodenal flow.

  9. Does supplemental feeding affect behaviour and foraging of ...

    African Journals Online (AJOL)

    In response to the provision of high-quality pods of Acacia albida, animals reduced foraging time in 2008 and allocated it to resting. This pattern corresponds to the animals' behaviour in captivity without foraging versus vigilance trade-offs and with predictable (in time and space) access to food. In 2009, supplemental ...

  10. Session B6 Management for sustainable use — Forage production ...

    African Journals Online (AJOL)

    Rangeland animal farming requires a continual supply of adequate quality forage to a) sustain animal output targets, b) facilitate flexibility to vary reproductive cycle dates for continuity of offtake, c) avoid enforced sale dates and d) alleviate the need to overgraze. The integration of herbaceous and/or woody forage to ...

  11. Vegetarian versus Meat-Based Diets for Companion Animals

    Directory of Open Access Journals (Sweden)

    Andrew Knight

    2016-09-01

    Full Text Available Companion animal owners are increasingly concerned about the links between degenerative health conditions, farm animal welfare problems, environmental degradation, fertilizers and herbicides, climate change, and causative factors; such as animal farming and the consumption of animal products. Accordingly, many owners are increasingly interested in vegetarian diets for themselves and their companion animals. However, are vegetarian canine and feline diets nutritious and safe? Four studies assessing the nutritional soundness of these diets were reviewed, and manufacturer responses to the most recent studies are provided. Additional reviewed studies examined the nutritional soundness of commercial meat-based diets and the health status of cats and dogs maintained on vegetarian and meat-based diets. Problems with all of these dietary choices have been documented, including nutritional inadequacies and health problems. However, a significant and growing body of population studies and case reports have indicated that cats and dogs maintained on vegetarian diets may be healthy—including those exercising at the highest levels—and, indeed, may experience a range of health benefits. Such diets must be nutritionally complete and reasonably balanced, however, and owners should regularly monitor urinary acidity and should correct urinary alkalinisation through appropriate dietary additives, if necessary.

  12. Painful dilemmas: the ethics of animal-based pain research

    DEFF Research Database (Denmark)

    Magalhães-Sant'Ana, M.; Sandøe, Peter; Olsson, I. A. S.

    2009-01-01

    While it has the potential to deliver important human benefits, animal-based pain research raises ethical questions, because it involves inducing pain in sentient beings. Ethical decision-making, connected with this variety of research, requires informed harm-benefit analysis, and the aim of this...

  13. MACROZOOBENTHOS OF MOUNTAIN RIVERS OF THE TRANSCARPATHIAN REGION AS A FORAGE BASE OF BENTHOPHAGOUS FISHES AND SAPROBITY INDICATOR

    Directory of Open Access Journals (Sweden)

    S. Kruzhylina

    2014-12-01

    Full Text Available Purpose. To study qualitative and qualitative indices of macrozoobenthos as one of main components of the forage base of benthophagous fishes in mountain river reaches of the Transcarpathian region and determination of their saprobity level. Methodology. Thhj,9.e study was carried out in summer period of 2009 in mountain river reaches of the Tisa river catchment. Zoobenthos samples were collected by a Surber sampler (25 × 25 cm on the bottoms of different fractions with different water flow rate (riffle, run, pool. Collection, processing and interpretation of the obtained data was carried out according to generally accepted hydrobiological methods developed for mountain river studies. Saprobity was of the studied rivers was calculated by Pantle-Buck formula. The Zelinka-Marvan saprobity index was used for calculations. Findings. Qualitative and quantitative macrozoobenthos indices have been studied. The number of zoobenthos on the investigated river sections ranged from 416 to 7712 ind./m2 with biomasses from 2.96 to 83.84 g/m2. The major portion of the zoobenthic biomass in the majority of rivers was due to caddis fly larvae composing up to 93% of the total biomass. An important role in the total biomass of the zoobenthos also belonged to mayfly (up to 53% and stonefly (up to 55% larvae and in lower degree amphipods (up to 39%, chironomid larvae (up to 14% and aquatic coleopterans (up to 5%. According to the calculated potential fish productivity, the mountain rivers can be apparently separated into three groups: little productive (4.2–12.7 kg/ha, medium productive (13.2–21.6 kg/ha and high productive (25.3–85.3 kg/ha. Mountain river reaches of the Transcarpathian region were found to belong to pure χ-saprobic, and о- і β-mesosaprobic zones, the saprobity index in which ranged from 0.35 (Rika river to 1.7 (Shipot river. Originality. For further calculation and assessment of brown trout (Salmo trutta and European grayling (Thymallus

  14. Emotional Metaheuristics For in-situ Foraging Using Sensor Constrained Robot Swarms

    OpenAIRE

    Kumar, Eshwaran Vijaya; Ghose, Debasish

    2017-01-01

    We present a new social animal inspired emotional swarm intelligence technique. This technique is used to solve a variant of the popular collective robots problem called foraging. We show with a simulation study how simple interaction rules based on sensations like hunger and loneliness can lead to globally coherent emergent behavior which allows sensor constrained robots to solve the given problem

  15. Produção de forragem e carga animal em pastagens de capim-elefante consorciadas com azevém, espécies de crescimento espontâneo e trevo-branco ou amendoim forrageiro Forage production an stocking rate on elephantgrass pastures mixed with ryegrass, spontaneous growth species and white clover or forage peanut

    Directory of Open Access Journals (Sweden)

    Clair Jorge Olivo

    2009-01-01

    Full Text Available Avaliaram-se a dinâmica e o desempenho de uma pastagem em dois sistemas forrageiros: SF1 - capim-elefante (CE + azevém (AZ + trevo-branco (TB + espécies de crescimento espontâneo (ECE; e SF2 - capim-elefante + azevém + amendoim forrageiro (AF + ECE. Utilizaram-se quatro piquetes de 0,25 ha com o capim-elefante estabelecido em linhas afastadas a cada 4 m, em delineamento de blocos ao acaso, com dois sistemas forrageiros e duas repetições (piquetes. As pastagens foram adubadas com N-P2O5-K2O (50-40-40 kg/ha/ano, respectivamente. Durante o período experimental, foram realizados nove pastejos (326 dias no SF1 e 336 dias no SF2. Foram usadas para avaliação vacas em lactação da raça Holandesa recebendo suplementação com concentrado (3,5 kg/dia. Foram colhidas no pré-pastejo amostras representativas da massa de forragem da pastagem nos piquetes. Os valores médios de matéria seca da massa de forragem da pastagem, de lâminas foliares do capim-elefante, do azevém e de leguminosas foram de 3,76; 0,85 e 0,26 t/ha no SF1 e 4,60; 0,99 e 0,19 t/ha no SF2, respectivamente. Considerando os períodos hibernal e estival, os valores médios da carga animal foram de 2,22 e 2,29 e de 3,14 e 3,01 UA/ha, respectivamente, para o SF1 e o SF2. Os resultados foram similares entre os sistemas forrageiros. Como o capim-elefante predomina nesses sistemas, a utilização do azevém, das leguminosas e das espécies de crescimento espontâneo permitiu manter a massa de forragem uniforme no decorrer dos pastejos. Os resultados sugerem que o capim-elefante pode ser utilizado segundo as misturas forrageiras propostas.The objective of this work was to evaluate the dynamic and animal performance in two pasture-based systems (PS, with elephantgrass (EG + ryegrass (RG + white clover (WC + spontaneous growing species (SGS for PS1; and EG + RG + forage peanut (FP + SGS for PS2. Four paddocks, each one with 0.25 ha, were used in the evaluation. EG was established in

  16. Animal anomalies and earthquake. [Earthquake forecasts based on the abnormal behavior of animals

    Energy Technology Data Exchange (ETDEWEB)

    Lan, C.

    1976-11-01

    Although earthquakes cannot yet be controlled, a great deal of evidence indicates that earthquakes will someday be mastered by men. In China, the earthquakes of Hai-ch'eng of South Liaoning on 2 February 1975, Lung-ling to Lu-hsi of Yunnan, and Sung-pan to P'ing-wu of Szechwan this year were successfully forecasted. The technique of forecasting earthquakes remains in need of being further perfected, however. This paper describes the abnormal reactions of over 80 species of animals just before an earthquake. Of these, the more accurate sources for forecasting include over 20 species of dogs, chickens, rodents, fish, birds, cats, and pigs. Through accumulation of feelings and heredity, the sense organs and nervous system possess a special ability to sense minute changes in the environment. The abnormal behaviors of the animals are perhaps reactions to certain physical or chemical changes, including changes of the electromagnetic field. Earthquake forecasting should be based upon comprehensive analyses of data including the abnormal behavior of animals observed by the masses.

  17. Determining spatio-temporal distribution of bee forage species of Al-Baha region based on ground inventorying supported with GIS applications and Remote Sensed Satellite Image analysis.

    Science.gov (United States)

    Adgaba, Nuru; Alghamdi, Ahmed; Sammoud, Rachid; Shenkute, Awraris; Tadesse, Yilma; Ansari, Mahammad J; Sharma, Deepak; Hepburn, Colleen

    2017-07-01

    In arid zones, the shortage of bee forage is critical and usually compels beekeepers to move their colonies in search of better forages. Identifying and mapping the spatiotemporal distribution of the bee forages over given area is important for better management of bee colonies. In this study honey bee plants in the target areas were inventoried following, ground inventory work supported with GIS applications. The study was conducted on 85 large plots of 50 × 50 m each. At each plot, data on species name, height, base diameter, crown height, crown diameter has been taken for each plant with their respective geographical positions. The data were stored, and processed using Trimble GPS supported with ArcGIS10 software program. The data were used to estimate the relative frequency, density, abundance and species diversity, species important value index and apicultural value of the species. In addition, Remotely Sensed Satellite Image of the area was obtained and processed using Hopfield Artificial Neural Network techniques. During the study, 182 species from 49 plant families were identified as bee forages of the target area. From the total number of species; shrubs, herbs and trees were accounting for 61%, 27.67%, and 11.53% respectively. Of which Ziziphus spina-christi , Acacia tortilis , Acacia origina , Acacia asak , Lavandula dentata , and Hypoestes forskaolii were the major nectar source plants of the area in their degree of importance. The average vegetation cover values of the study areas were low (GIS and satellite image processing techniques could be an important tool for characterizing and mapping the available bee forage resources leading to their efficient and sustainable utilization.

  18. Visual Foraging With Fingers and Eye Gaze

    Directory of Open Access Journals (Sweden)

    Ómar I. Jóhannesson

    2016-03-01

    Full Text Available A popular model of the function of selective visual attention involves search where a single target is to be found among distractors. For many scenarios, a more realistic model involves search for multiple targets of various types, since natural tasks typically do not involve a single target. Here we present results from a novel multiple-target foraging paradigm. We compare finger foraging where observers cancel a set of predesignated targets by tapping them, to gaze foraging where observers cancel items by fixating them for 100 ms. During finger foraging, for most observers, there was a large difference between foraging based on a single feature, where observers switch easily between target types, and foraging based on a conjunction of features where observers tended to stick to one target type. The pattern was notably different during gaze foraging where these condition differences were smaller. Two conclusions follow: (a The fact that a sizeable number of observers (in particular during gaze foraging had little trouble switching between different target types raises challenges for many prominent theoretical accounts of visual attention and working memory. (b While caveats must be noted for the comparison of gaze and finger foraging, the results suggest that selection mechanisms for gaze and pointing have different operational constraints.

  19. A generic individual-based model to simulate morphogenesis, C-N acquisition and population dynamics in contrasting forage legumes.

    Science.gov (United States)

    Louarn, Gaëtan; Faverjon, Lucas

    2017-12-29

    Individual-based models (IBMs) are promising tools to disentangle plant interactions in multi-species grasslands and foster innovative species mixtures. This study describes an IBM dealing with the morphogenesis, growth and C-N acquisition of forage legumes that integrates plastic responses from functional-structural plant models. A generic model was developed to account for herbaceous legume species with contrasting above- and below-ground morphogenetic syndromes and to integrate the responses of plants to light, water and N. Through coupling with a radiative transfer model and a three-dimensional virtual soil, the model allows dynamic resolution of competition for multiple resources at individual plant level within a plant community. The behaviour of the model was assessed on a range of monospecific stands grown along gradients of light, water and N availability. The model proved able to capture the diversity of morphologies encountered among the forage legumes. The main density-dependent features known about even-age plant populations were correctly anticipated. The model predicted (1) the 'reciprocal yield' law relating average plant mass to density, (2) a self-thinning pattern close to that measured for herbaceous species and (3) consistent changes in the size structure of plant populations with time and pedo-climatic conditions. In addition, plastic changes in the partitioning of dry matter, the N acquisition mode and in the architecture of shoots and roots emerged from the integration of plant responses to their local environment. This resulted in taller plants and thinner roots when competition was dominated by light, and shorter plants with relatively more developed root systems when competition was dominated by soil resources. A population dynamic model considering growth and morphogenesis responses to multiple resources heterogeneously distributed in the environment was presented. It should allow scaling plant-plant interactions from individual to

  20. Forage Polyphenol Oxidase and Ruminant Livestock Nutrition

    Directory of Open Access Journals (Sweden)

    Michael Richard F. Lee

    2014-12-01

    Full Text Available Polyphenol oxidase (PPO is associated with the detrimental effect of browning fruit and vegetables, however interest within PPO containing forage crops has grown since the brownng reaction was associated with reduced nitrogen (N losses in silo and the rumen. The reduction in protein breakdown in silo of red clover (high PPO forage increased the quality of protein, improving N-use efficiency (NUE when fed to ruminants. A further benefit of red clover silage feeding is a significant reduction in lipolysis in silo and an increase in the deposition of beneficial C18 polyunsaturated fatty acid (PUFA in animal products, which has also been linked to PPO activity. PPOs protection of plant protein and glycerol based-PUFA in silo is related to the deactivation of plant proteases and lipases. This deactivation occurs through PPO catalysing the conversion of diphenols to quinones which bind with cellular nucleophiles such as protein reforming a protein-bound phenol (PBP. If the protein is an enzyme the complexing denatures the enzyme. However, PPO is inactive in the anaerobic rumen and therefore any subsequent protection of plant protein and glycerol based-PUFA in the rumen must be as a result of events that occurred to the forage pre-ingestion. Reduced activity of plant proteases and lipases would have little effect on NUE and glycerol based-PUFA in the rumen due to the greater concentration of rumen microbial proteases and lipases. The mechanism for PPOs protection of plant protein in the rumen is a consequence of complexing plant protein, rather than protease deactivation per se. These complexed proteins reduce protein digestibility in the rumen and subsequently increase un-degraded dietary protein flow to the small intestine. The mechanism for protecting glycerol-based PUFA has yet to be fully elucidated but may be associated with entrapment within PBP reducing access to microbial lipases or differences in rumen digestion kinetics of red clover.

  1. Forage nutritive value of plant samples collected by clipping or rumen evacuation

    Science.gov (United States)

    Knowing nutritive value and intake of forage by an animal is important to understand methane production data from individual animals in a grazed environment. Digestibility of forages is typically evaluated as the in vitro dry matter disappearance (IVDMD) using a clipped forage sample; however, beef...

  2. Heat Damaged Forages: Effects on Forage Quality

    Science.gov (United States)

    Traditionally, heat damage in forages has been associated with alterations in forage protein quality as a result of Maillard reactions, and most producers and nutritionists are familiar with this concept. However, this is not necessarily the most important negative consequence of spontaneous heating...

  3. Is there an endogenous tidal foraging rhythm in marine iguanas?

    Science.gov (United States)

    Wikelski, M; Hau, M

    1995-12-01

    As strictly herbivorous reptiles, Galápagos marine iguanas graze on algae in the intertidal areas during low tide. Daily foraging rhythms were observed on two islands during 3 years to determine the proximate factors underlying behavioral synchrony with the tides. Marine iguanas walked to their intertidal foraging grounds from far-off resting areas in anticipation of the time of low tide. Foraging activity was restricted to daytime, resulting in a complex bitidal rhythm including conspicuous switches from afternoon foraging to foraging during the subsequent morning when low tide occurred after dusk. The animals anticipated the daily low tide by a maximum of 4 h. The degree of anticipation depended on environmental parameters such as wave action and food supply. "Early foragers" survived in greater numbers than did animals arriving later at foraging sites, a result indicating selection pressure on the timing of anticipation. The timing of foraging trips was better predicted by the daily changes in tabulated low tide than it was by the daily changes in actual exposure of the intertidal foraging flats, suggesting an endogenous nature of the foraging rhythms. Endogenous rhythmicity would also explain why iguanas that had spontaneously fasted for several days nevertheless went foraging at the "right" time of day. A potential lunar component of the foraging rhythmicity of marine iguanas showed up in their assemblage on intertidal rocks during neap tide nights. This may indicate that iguanas possessed information on the semi-monthly rhythms in tide heights. Enclosure experiments showed that bitidal foraging rhythms of iguanas may free run in the absence of direct cues from the intertidal areas and operate independent of the light:dark cycle and social stimuli. Therefore, the existence of a circatidal oscillator in marine iguanas is proposed. The bitidal foraging pattern may result from an interaction of a circadian system with a circatidal system. Food intake or related

  4. LivestockPlus: Forages, sustainable intensification, and food security in the tropics.

    Science.gov (United States)

    Rudel, Thomas K; Paul, Birthe; White, Douglas; Rao, I M; Van Der Hoek, Rein; Castro, Aracely; Boval, Maryline; Lerner, Amy; Schneider, Laura; Peters, Michael

    2015-11-01

    The increased use of grain-based feed for livestock during the last two decades has contributed, along with other factors, to a rise in grain prices that has reduced human food security. This circumstance argues for feeding more forages to livestock, particularly in the tropics where many livestock are reared on small farms. Efforts to accomplish this end, referred to as the 'LivestockPlus' approach, intensify in sustainable ways the management of grasses, shrubs, trees, and animals. By decoupling the human food and livestock feed systems, these efforts would increase the resilience of the global food system. Effective LivestockPlus approaches take one of two forms: (1) simple improvements such as new forage varieties and animal management practices that spread from farmer to farmer by word of mouth, or (2) complex sets of new practices that integrate forage production more closely into farms' other agricultural activities and agro-ecologies.

  5. Risso's dolphins plan foraging dives.

    Science.gov (United States)

    Arranz, Patricia; Benoit-Bird, Kelly J; Southall, Brandon L; Calambokidis, John; Friedlaender, Ari S; Tyack, Peter L

    2018-02-28

    Humans remember the past and use that information to plan future actions. Lab experiments that test memory for the location of food show that animals have a similar capability to act in anticipation of future needs, but less work has been done on animals foraging in the wild. We hypothesized that planning abilities are critical and common in breath-hold divers who adjust each dive to forage on prey varying in quality, location and predictability within constraints of limited oxygen availability. We equipped Risso's dolphins with sound-and-motion recording tags to reveal where they focus their attention through their externally observable echolocation and how they fine tune search strategies in response to expected and observed prey distribution. The information from the dolphins was integrated with synoptic prey data obtained from echosounders on an underwater vehicle. At the start of the dives, whales adjusted their echolocation inspection ranges in ways that suggest planning to forage at a particular depth. Once entering a productive prey layer, dolphins reduced their search range comparable to the scale of patches within the layer, suggesting that they were using echolocation to select prey within the patch. On ascent, their search range increased, indicating that they decided to stop foraging within that layer and started searching for prey in shallower layers. Information about prey, learned throughout the dive, was used to plan foraging in the next dive. Our results demonstrate that planning for future dives is modulated by spatial memory derived from multi-modal prey sampling (echoic, visual and capture) during earlier dives. © 2018. Published by The Company of Biologists Ltd.

  6. Produção de forragem e desempenho animal em pastagens de coastcross consorciada ou não com Arachis pintoi, com e sem nitrogênio = Forage Production and Performance Animal in Coastcross Intercropping or not with Arachis pintoi, with or without Nitrogen

    Directory of Open Access Journals (Sweden)

    Ossival Lolato Ribeiro

    2008-10-01

    Full Text Available O estudo objetivou avaliar a produção de forragem e desempenho animal em pastagens de Coastcross + Arachis pintoi; Coastcross + Arachis pintoi com 100 kg ha-1 de N; Coastcross + Arachis pintoi com 200 kg ha-1 de N e Coastcross com 200 kg ha-1 de N, nas estações de inverno, primavera, verão e outono. Utilizou-se o delineamento experimentalem blocos ao acaso, com os tratamentos em parcelas subdivididas, com duas repetições. Foram avaliados: acúmulo de massa de forragem e acúmulo diário de massa de forragem, ganho médio diário (GMD, ganho de peso vivo por área e taxa de lotação. A utilização de Coastcross + 200 kg ha-1 de N e as melhores condições climáticas na primavera e verão favoreceram tanto o acúmulo de massa de forragem (26.764 kg ha-1 de MS quanto o acúmulo diário de massa de forragem (82 kg ha-1 por dia de MS. A utilização da associação entre Arachis pintoi + 200 kg ha-1 de N e Coastcross + 200 kg ha-1 de N, possibilitou o melhor desempenho animal, com GMD de 0,570 e 0,500 kg e taxa de lotação de 3,51 e 3,26 UA ha-1, respectivamente. A utilização de pastagem consorciada sem a associação com doses de nitrogênio (100 e 200 kg ha-1 não favoreceu (p > 0,05 o acúmulo de massa de forrageme a taxa de acúmulo diária. A utilização de 200 kg ha-1 de N, com e sem a leguminosa, proporcionou o melhor desempenho e lotação animal por área.The objective of this study was to evaluate dry matter production and animal performance in pastures of Coastcross + Arachis pintoi; Coastcross + Arachis pintoi with 100 kg ha-1 of N; Coastcross +Arachis pintoi with 200 kg ha-1 of N and Coastcross with 200 kg ha-1 of N, during winter, spring, summer and autumn. The experimental design was complete randomized blocks with split-plot parcels, with two repetitions. The study evaluated the accumulation of foragemass and dairy accumulation of forage mass, average daily gain (ADG, live weight gain and stocking rate. The used of

  7. Group foraging increases foraging efficiency in a piscivorous diver, the African penguin

    Science.gov (United States)

    McGeorge, Cuan; Ginsberg, Samuel; Pichegru, Lorien; Pistorius, Pierre A.

    2017-01-01

    Marine piscivores have evolved a variety of morphological and behavioural adaptations, including group foraging, to optimize foraging efficiency when targeting shoaling fish. For penguins that are known to associate at sea and feed on these prey resources, there is nonetheless a lack of empirical evidence to support improved foraging efficiency when foraging with conspecifics. We examined the hunting strategies and foraging performance of breeding African penguins equipped with animal-borne video recorders. Individuals pursued both solitary as well as schooling pelagic fish, and demonstrated independent as well as group foraging behaviour. The most profitable foraging involved herding of fish schools upwards during the ascent phase of a dive where most catches constituted depolarized fish. Catch-per-unit-effort was significantly improved when targeting fish schools as opposed to single fish, especially when foraging in groups. In contrast to more generalist penguin species, African penguins appear to have evolved specialist hunting strategies closely linked to their primary reliance on schooling pelagic fish. The specialist nature of the observed hunting strategies further limits the survival potential of this species if Allee effects reduce group size-related foraging efficiency. This is likely to be exacerbated by diminishing fish stocks due to resource competition and environmental change. PMID:28989785

  8. Desempenho animal, produção de forragem e características estruturais dos capins marandu e xaraés submetidos a intensidades de pastejo Animal performance, forage yield and structural characteristics in the palisadegrass cvs. marandu and xaraés submitted to grazing intensities

    Directory of Open Access Journals (Sweden)

    Renata Santos Flores

    2008-08-01

    palisadegrass cvs. Marandu and Xaraés pastures submitted to three grazing intensities. The experiment was carried out at Embrapa Gado de Corte. The experimental period was from October 2005 to June 2006. The area was of 8 ha, divided in 12 paddocks of 0.67 ha. Two cultivars of palisadegrass, Marandu and Xaraés, and three grazing intensities, 15, 30, and 45 cm of sward height were evaluated. The experimental design was randomized block in a split plot arrangement and two replications. The main plot was constituted by cultivars and the subplot by the grazing intensities. The grazing was continuously stocking with variable stocking rate. Each paddock was grazed by three steers and regulating animals were utilized to adjust the sward heights. The sward heights were monitored twice per week. The grass was sampled each 28 days to estimate the herbage yield, herbage accumulation rate, pasture structural characteristics, and nutritive value. Animals were weighed each 28 days. The dry matter intake was estimated in the summer and the autumn, and the grazing behavior in the summer. Herbage accumulation and average daily gain decreased as the grazing intensities increased for both palisadegrass cvs. Xaraés and Marandu. The forage intake for the animals in xaraés grass pasture was limited by the variation in the sward structure. Based on the sward structural characteristics, forage intake and the productivity, these grasses require differentiated management. Marandu grass must be managed between 25 and 40 cm of height and xaraés grass at 40 cm.

  9. Effect of source of trace minerals in either forage- or by-product-based diets fed to dairy cows: 2. Apparent absorption and retention of minerals.

    Science.gov (United States)

    Faulkner, M J; St-Pierre, N R; Weiss, W P

    2017-07-01

    Eighteen multiparous cows were used in a split-plot replicated Latin square with two 28-d periods to evaluate the effects of source of supplemental Cu, Zn, and Mn (sulfates or hydroxy) on apparent absorption of minerals when fed in either a forage- or by-product-based diet. The by-product diets were formulated to have greater concentrations of NDF and lesser concentrations of starch, and specific ingredients were chosen because they were good sources of soluble fiber and β-glucans, which bind trace minerals in nonruminants. We hypothesized that hydroxy trace minerals would interact less with digesta and have greater apparent absorption compared with sulfate minerals, and the difference in apparent absorption would be greater for the by-product diet compared with the forage-based diet. During the 56-d experiment, cows remained on the same fiber treatment but source of supplemental trace mineral was different for each 28-d period; thus, all cows were exposed to both mineral treatments. During each period cows were fed no supplemental Cu, Zn, or Mn for 16 d, followed by 12 d of feeding supplemental minerals from either sulfate or hydroxy sources. Supplemental minerals for each of the mineral sources fed provided approximately 10, 35, and 32 mg/kg of supplemental Cu, Zn, and Mn, respectively, for both fiber treatments. Total Cu, Zn, and Mn dietary concentrations, respectively, were approximately 19, 65, and 70 mg/kg for the forage diets and 21, 85, and 79 for the by-product diets. Treatment had no effect on dry matter intake (24.2 kg/d) or milk production (34.9 kg/d). Cows consuming the by-product diets had greater Zn (1,863 vs. 1,453 mg/d) and Mn (1,790 vs. 1,588 mg/d) intake compared with cows fed forage diets, but apparent Zn absorption was similar between treatments. Manganese apparent absorption was greater for the by-product diets compared with the forage diets (16 vs. 11%). A fiber by mineral interaction was observed for Cu apparent absorption, as cows fed

  10. Animal Recognition System Based on Convolutional Neural Network

    Directory of Open Access Journals (Sweden)

    Tibor Trnovszky

    2017-01-01

    Full Text Available In this paper, the performances of well-known image recognition methods such as Principal Component Analysis (PCA, Linear Discriminant Analysis (LDA, Local Binary Patterns Histograms (LBPH and Support Vector Machine (SVM are tested and compared with proposed convolutional neural network (CNN for the recognition rate of the input animal images. In our experiments, the overall recognition accuracy of PCA, LDA, LBPH and SVM is demonstrated. Next, the time execution for animal recognition process is evaluated. The all experimental results on created animal database were conducted. This created animal database consist of 500 different subjects (5 classes/ 100 images for each class. The experimental result shows that the PCA features provide better results as LDA and LBPH for large training set. On the other hand, LBPH is better than PCA and LDA for small training data set. For proposed CNN we have obtained a recognition accuracy of 98%. The proposed method based on CNN outperforms the state of the art methods.

  11. Social Differentiation in Common Bottlenose Dolphins (Tursiops truncatus) that Engage in Human-Related Foraging Behaviors

    Science.gov (United States)

    2017-01-01

    Both natural and human-related foraging strategies by the common bottlenose dolphin (Tursiops truncatus) have resulted in social segregation in several areas of the world. Bottlenose dolphins near Savannah, Georgia beg at an unprecedented rate and also forage behind commercial shrimp trawlers, providing an opportunity to study the social ramifications of two human-related foraging behaviors within the same group of animals. Dolphins were photo-identified via surveys conducted throughout estuarine waterways around Savannah in the summers of 2009–2011. Mean half-weight indices (HWI) were calculated for each foraging class, and community division by modularity was used to cluster animals based on association indices. Pairs of trawler dolphins had a higher mean HWI (0.20 ± 0.07) than pairs of non-trawler dolphins (0.04 ± 0.02) or mixed pairs (0.02 ± 0.02). In contrast, pairs of beggars, non-beggars, and mixed pairs all had similar means, with HWI between 0.05–0.07. Community division by modularity produced a useful division (0.307) with 6 clusters. Clusters were predominately divided according to trawler status; however, beggars and non-beggars were mixed throughout clusters. Both the mean HWI and social clusters revealed that the social structure of common bottlenose dolphins near Savannah, Georgia was differentiated based on trawler status but not beg status. This finding may indicate that foraging in association with trawlers is a socially learned behavior, while the mechanisms for the propagation of begging are less clear. This study highlights the importance of taking into account the social parameters of a foraging behavior, such as how group size or competition for resources may affect how the behavior spreads. The positive or negative ramifications of homophily may influence whether the behaviors are exhibited by individuals within the same social clusters and should be considered in future studies examining social relationships and foraging behaviors

  12. Fecal microbiome of growing pigs fed a cereal based diet including chicory (Cichorium intybus L.) or ribwort (Plantago lanceolata L.) forage

    Energy Technology Data Exchange (ETDEWEB)

    Dicksved, Johan; Jansson, Janet K.; Lindberg, Jan Erik

    2015-12-01

    BACKGROUND: The purpose of this study was to investigate how inclusion of chicory forage or ribwort forage in a cereal-based diet influenced the fecal microbial community (microbiome) in newly weaned (35 days of age) piglets. The piglets were fed a cereal-based diet without (B) and with inclusion (80 and 160 g/kg air-dry forage) of vegetative shoots of chicory (C) and leaves of ribwort (R) forage in a 35-day growth trial. Fecal samples were collected at the start (D0), 17 (D17) and 35 (D35) days after weaning and profiles of the microbial consortia were generated using terminal restriction fragment length polymorphism (T-RFLP). 454-FLX pyrosequencing of 16S rRNA gene amplicons was used to analyze the microbial composition in a subset of the samples already analyzed with T-RFLP. RESULTS: The microbial clustering pattern was primarily dependent on age of the pigs, but diet effects could also be observed. Lactobacilli and enterobacteria were more abundant at D0, whereas the genera Streptococcus, Treponema, Clostridium, Clostridiaceae1 and Coprococcus were present in higher abundances at D35. Pigs fed ribwort had an increased abundance of sequences classified as Treponema and a reduction in lactobacilli. However, the abundance of Prevotellaceae increased with age in on both the chicory and the ribwort diet. Moreover, there were significant correlations between the abundance of Bacteroides and the digested amount of galactose, uronic acids and total non-starch polysaccharides, and between the abundance of Bacteroidales and the digested amount of xylose. CONCLUSION: This study demonstrated that both chicory and ribwort inclusion in the diet of newly weaned pigs influenced the composition of the fecal microbiota and that digestion of specific dietary components was correlated with species composition of the microbiota. Moreover, this study showed that the gut will be exposed to a dramatic shift in the microbial community structure several weeks after weaning.

  13. Nitrogen management in grasslands and forage-based production systems – Role of biological nitrification inhibition (BNI

    Directory of Open Access Journals (Sweden)

    G.V. Subbarao

    2013-12-01

    Full Text Available Nitrogen (N, the most critical and essential nutrient for plant growth, largely determines the productivity in both extensive and intensive grassland systems. Nitrification and denitrification processes in the soil are the primary drivers of generating reactive N (NO3-, N2O and NO, largely responsible for N loss and degradation of grasslands. Suppressing nitrification can thus facilitate retention of soil N to sustain long-term productivity of grasslands and forage-based production systems. Certain plants can suppress soil nitrification by releasing inhibitors from roots, a phenomenon termed ‘biological nitrification inhibition’ (BNI. Recent methodological developments [e.g. bioluminescence assay to detect biological nitrification inhibitors (BNIs from plant-root systems] led to significant advances in our ability to quantify and characterize BNI function in pasture grasses. Among grass pastures, BNI capacity is strongest in low-N environment grasses such as Brachiaria humidicola and weakest in high-N environment grasses such as Italian ryegrass (Lolium perenne and B. brizantha. The chemical identity of some of the BNIs produced in plant tissues and released from roots has now been established and their mode of inhibitory action determined on nitrifying Nitrosomonas bacteria. Synthesis and release of BNIs is a highly regulated and localized process, triggered by the presence of NH4+ in the rhizosphere, which facilitates release of BNIs close to soil-nitrifier sites. Substantial genotypic variation is found for BNI capacity in B. humidicola, which opens the way for its genetic manipulation. Field studies suggest that Brachiaria grasses suppress nitrification and N2O emissions from soil. The potential for exploiting BNI function (from a genetic improvement and a system perspective to develop production systems, that are low-nitrifying, low N2O-emitting, economically efficient and ecologically sustainable, is discussed.

  14. Caffeinated forage tricks honeybees into increasing foraging and recruitment behaviors.

    Science.gov (United States)

    Couvillon, Margaret J; Al Toufailia, Hasan; Butterfield, Thomas M; Schrell, Felix; Ratnieks, Francis L W; Schürch, Roger

    2015-11-02

    In pollination, plants provide food reward to pollinators who in turn enhance plant reproduction by transferring pollen, making the relationship largely cooperative; however, because the interests of plants and pollinators do not always align, there exists the potential for conflict, where it may benefit both to cheat the other [1, 2]. Plants may even resort to chemistry: caffeine, a naturally occurring, bitter-tasting, pharmacologically active secondary compound whose main purpose is to detract herbivores, is also found in lower concentrations in the nectar of some plants, even though nectar, unlike leaves, is made to be consumed by pollinators. [corrected]. A recent laboratory study showed that caffeine may lead to efficient and effective foraging by aiding honeybee memory of a learned olfactory association [4], suggesting that caffeine may enhance bee reward perception. However, without field data, the wider ecological significance of caffeinated nectar remains difficult to interpret. Here we demonstrate in the field that caffeine generates significant individual- and colony-level effects in free-flying worker honeybees. Compared to a control, a sucrose solution with field-realistic doses of caffeine caused honeybees to significantly increase their foraging frequency, waggle dancing probability and frequency, and persistency and specificity to the forage location, resulting in a quadrupling of colony-level recruitment. An agent-based model also demonstrates how caffeine-enhanced foraging may reduce honey storage. Overall, caffeine causes bees to overestimate forage quality, tempting the colony into sub-optimal foraging strategies, which makes the relationship between pollinator and plant less mutualistic and more exploitative. VIDEO ABSTRACT. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Alfalfa (Medicago sativa L.) forage production, tissue and soil nutrient concentration under three N based broiler litter regimes

    Science.gov (United States)

    Alfalfa (Medicago sativa L.) is considered as most important forage legume grown in Kentucky. Alfalfa supports many livestock production systems including the beef, dairy, and horse industries in Kentucky. Being a legume, alfalfa typically meets its N requirement through symbiotic N2 fixation, but h...

  16. A new animal welfare concept based on allostasis

    OpenAIRE

    Korte, S.M.; Olivier, B.; Koolhaas, J.M.

    2007-01-01

    Animal welfare is an increasing issue of public concern and debate. As a result, many countries are reconsidering the way animal welfare is embedded in the legislation and rules for housing and care of animals. This requires general agreement of what animal welfare is. Unfortunately, the current science of animal welfare is less scientific than what has been claimed. In our view, it is overly guided by anthropocentric thinking about how animals ought to be handled and neglects the latest conc...

  17. New approach for determination of an optimum honeybee colony’s carrying capacity based on productivity and nectar secretion potential of bee forage species

    Science.gov (United States)

    Al-Ghamdi, Ahmed; Adgaba, Nuru; Getachew, Awraris; Tadesse, Yilma

    2014-01-01

    The present study was carried out to determine an optimum honeybee colony’s carrying capacity of selected valleys dominated by Ziziphus spina-christi and Acacia tortilis in the Al-Baha region, Kingdom of Saudi Arabia. The study was conducted based on the assessment of the number of colonies kept, their productivities and the existing productive bee forage resources in the target valleys with its economic implication. In the existing beekeeping practice, the average number of managed honeybee colonies introduced per square kilometer was 530 and 317 during the flowering period of Z. spina-christi and A. tortilis, respectively. Furthermore, the overall ratios of productive bee forage plants to the number of honeybee colonies introduced were 0.55 and 11.12 to Ziziphus trees and A. tortilis shrubs respectively. In the existing situation the average honey production potential of 5.21 and 0.34 kg was recorded per Ziziphus and A. tortilis plants per flowering season, respectively. The present study, revealed that the number of honeybee colonies introduced in relation to the existing bee forage potential was extremely overcrowding which is beyond the carrying capacity of bee forage resources in selected valleys and it has been observed to affect the productivities and subsequent profitability of beekeeping. The study infers that, by keeping the optimum honeybee colony’s carrying capacity of valleys (88 traditional hives/km2 or 54 Langstroth hives/km2 in Ziziphus field and 72 traditional hives/km2 or 44 Langstroth hives/km2 in A. tortilis field), profitability of beekeeping can be boosted up to 130.39% and 207.98% during Z. spina-christi and A. tortilis, flowering seasons, respectively. PMID:26858544

  18. New approach for determination of an optimum honeybee colony's carrying capacity based on productivity and nectar secretion potential of bee forage species.

    Science.gov (United States)

    Al-Ghamdi, Ahmed; Adgaba, Nuru; Getachew, Awraris; Tadesse, Yilma

    2016-01-01

    The present study was carried out to determine an optimum honeybee colony's carrying capacity of selected valleys dominated by Ziziphus spina-christi and Acacia tortilis in the Al-Baha region, Kingdom of Saudi Arabia. The study was conducted based on the assessment of the number of colonies kept, their productivities and the existing productive bee forage resources in the target valleys with its economic implication. In the existing beekeeping practice, the average number of managed honeybee colonies introduced per square kilometer was 530 and 317 during the flowering period of Z. spina-christi and A. tortilis, respectively. Furthermore, the overall ratios of productive bee forage plants to the number of honeybee colonies introduced were 0.55 and 11.12 to Ziziphus trees and A. tortilis shrubs respectively. In the existing situation the average honey production potential of 5.21 and 0.34 kg was recorded per Ziziphus and A. tortilis plants per flowering season, respectively. The present study, revealed that the number of honeybee colonies introduced in relation to the existing bee forage potential was extremely overcrowding which is beyond the carrying capacity of bee forage resources in selected valleys and it has been observed to affect the productivities and subsequent profitability of beekeeping. The study infers that, by keeping the optimum honeybee colony's carrying capacity of valleys (88 traditional hives/km(2) or 54 Langstroth hives/km(2) in Ziziphus field and 72 traditional hives/km(2) or 44 Langstroth hives/km(2) in A. tortilis field), profitability of beekeeping can be boosted up to 130.39% and 207.98% during Z. spina-christi and A. tortilis, flowering seasons, respectively.

  19. Animal density and track counts: understanding the nature of observations based on animal movements.

    Directory of Open Access Journals (Sweden)

    Derek Keeping

    Full Text Available Counting animals to estimate their population sizes is often essential for their management and conservation. Since practitioners frequently rely on indirect observations of animals, it is important to better understand the relationship between such indirect indices and animal abundance. The Formozov-Malyshev-Pereleshin (FMP formula provides a theoretical foundation for understanding the relationship between animal track counts and the true density of species. Although this analytical method potentially has universal applicability wherever animals are readily detectable by their tracks, it has long been unique to Russia and remains widely underappreciated. In this paper, we provide a test of the FMP formula by isolating the influence of animal travel path tortuosity (i.e., convolutedness on track counts. We employed simulations using virtual and empirical data, in addition to a field test comparing FMP estimates with independent estimates from line transect distance sampling. We verify that track counts (total intersections between animals and transects are determined entirely by density and daily movement distances. Hence, the FMP estimator is theoretically robust against potential biases from specific shapes or patterns of animal movement paths if transects are randomly situated with respect to those movements (i.e., the transects do not influence animals' movements. However, detectability (the detection probability of individual animals is not determined simply by daily travel distance but also by tortuosity, so ensuring that all intersections with transects are counted regardless of the number of individual animals that made them becomes critical for an accurate density estimate. Additionally, although tortuosity has no bearing on mean track encounter rates, it does affect encounter rate variance and therefore estimate precision. We discuss how these fundamental principles made explicit by the FMP formula have widespread implications for

  20. Evidence-Based Advances in Aquatic Animal Medicine.

    Science.gov (United States)

    Vergneau-Grosset, Claire; Larrat, Sylvain

    2017-09-01

    Fish and aquatic invertebrates deserve evidence-based medicine. Pharmacologic information is available; most pharmacokinetic studies are derived from the aquaculture industry and extrapolated to ornamental fish. Conversely, advanced diagnostics and information regarding diseases affecting only ornamental fish and invertebrates require more peer-reviewed experimental studies; the examples of carp edema virus, sea star wasting disease, seahorse nutrition, and gas bubble disease of fish under human care are discussed. Antinociception is also a controversial topic of growing interest in aquatic animal medicine. This article summarizes information regarding new topics of interest in companion fish and invertebrates and highlights some future avenues for research. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Bioconcentration of some macrominerals in soil, forage and buffalo hair continuum: A case study on pasture irrigated with sewage water.

    Science.gov (United States)

    Khan, Zafar Iqbal; Ahmad, Kafeel; Ashraf, Iqra; Gondal, Sumaira; Sher, Muhammad; Hayat, Zafar; Laudadio, Vito; Tufarelli, Vincenzo

    2015-05-01

    The present study aimed to evaluate the bioaccumulation of some macrominerals in grazing buffaloes fed forage irrigated with sewage water or canal water. In particular, the transfer of sodium (Na), magnesium (Mg), potassium (K) and calcium (Ca) from soil to plant and in turn to animals was evaluated under sub-tropical environmental conditions. Samples of soil, forage and buffalo hair were collected and digested by wet method. Sodium and K concentrations were significantly higher in the soil but lower in the forages; however, Mg and Ca concentrations in both soil and forages were higher. The correlation between soil, forage and hair showed an imbalanced flow of Na, Mg and K and a balanced flow of Ca from soil to forage and then to animals. Based on the findings, the highest rates of transfer of minerals were found for sewage water treatment, whereas lowest rates were found for canal water treatment, except for Na. As the transfer of minerals depends on their bioavailability, the highest values may be due to the high rates of mineral uptake by plants. Thus, the high transfer rate of some elements by plants could become toxic in future causing detrimental effect to grazing livestock.

  2. Veld condition and animal performance: application of an optimal ...

    African Journals Online (AJOL)

    Keywords: Diet choices; Food ingestion; Foraging models; Grassland conditions; Herbivores; animal performance; animal production; diet choice; digestion rate; grazing; needs; quality; veld condition score; condition; performance; grassland; production; foraging; model; food; ingestion; digestion; food preferences; food ...

  3. A new animal welfare concept based on allostasis

    NARCIS (Netherlands)

    Korte, S.M.; Olivier, B.; Koolhaas, J.M.

    2007-01-01

    Animal welfare is an increasing issue of public concern and debate. As a result, many countries are reconsidering the way animal welfare is embedded in the legislation and rules for housing and care of animals. This requires general agreement of what animal welfare is. Unfortunately, the current

  4. Optimally frugal foraging

    Science.gov (United States)

    Bénichou, O.; Bhat, U.; Krapivsky, P. L.; Redner, S.

    2018-02-01

    We introduce the frugal foraging model in which a forager performs a discrete-time random walk on a lattice in which each site initially contains S food units. The forager metabolizes one unit of food at each step and starves to death when it last ate S steps in the past. Whenever the forager eats, it consumes all food at its current site and this site remains empty forever (no food replenishment). The crucial property of the forager is that it is frugal and eats only when encountering food within at most k steps of starvation. We compute the average lifetime analytically as a function of the frugality threshold and show that there exists an optimal strategy, namely, an optimal frugality threshold k* that maximizes the forager lifetime.

  5. Roles of NMDA and dopamine in food-foraging decision-making strategies of rats in the social setting.

    Science.gov (United States)

    Li, Fang; Cao, Wen-Yu; Huang, Fu-Lian; Kang, Wen-Jing; Zhong, Xiao-Lin; Hu, Zhao-Lan; Wang, Hong-Tao; Zhang, Juan; Zhang, Jian-Yi; Dai, Ru-Ping; Zhou, Xin-Fu; Li, Chang-Qi

    2016-01-11

    In highly complex social settings, an animal's motivational drive to pursue an object depends not only on the intrinsic properties of the object, but also on whether the decision-making animal perceives an object as being the most desirable among others. Mimetic desire refers to a subject's preference for objects already possessed by another subject. To date, there are no appropriate animal models for studying whether mimetic desire is at play in guiding the decision-making process. Furthermore, the neuropharmacological bases of decision-making processes are not well understood. In this study, we used an animal model (rat) to investigate a novel food-foraging paradigm for decision-making, with or without a mimetic desire paradigm. Faced with the choice of foraging in a competitive environment, rats preferred foraging for the desirable object, indicating the rats' ability for decision-making. Notably, treatment with the non-competitive N-methyl-D-aspartate receptor antagonist MK-801, but not with the dopamine D1 or D2 receptor antagonists, SCH23390 and haloperidol, respectively, suppressed the food foraging preference when there was a competing resident rat in the cage. None of these three antagonists affected the food-foraging preference for palatable food. Moreover, MK-801 and SCH23390, but not haloperidol, were able to abolish the desirable environment effect on standard food-foraging activities in complex social settings. These results highlight the concept that mimetic desire exerts a powerful influence on food-foraging decision-making in rats and, further, illustrate the various roles of the glutamatergic and dopaminergic systems in mediating these processes.

  6. Female mice respond differently to costly foraging versus food restriction

    NARCIS (Netherlands)

    Schubert, Kristin A.; Vaanholt, Lobke M.; Stavasius, Fanny; Demas, Gregory E.; Daan, Serge; Visser, G. Henk

    2008-01-01

    Experimental manipulation of foraging costs per food reward can be used to study the plasticity of physiological systems involved in energy metabolism. This approach is useful for understanding adaptations to natural variation in food availability. Earlier studies have shown that animals foraging on

  7. development of oscillating classifiers for forage chop length ...

    African Journals Online (AJOL)

    Dr Obe

    1987-09-01

    Sep 1, 1987 ... size is defined. The size of the particles are reported in terms of geometric mean length and geometric standard deviation by weight. The particle size determined is used to evaluate forage harvesting machine and to define forage characteristics with regards to animal feeding trials. 1. INTRODUCTION.

  8. Animal vaccines based on orally presented yeast recombinants.

    Science.gov (United States)

    Shin, Min-Kyoung; Yoo, Han Sang

    2013-09-13

    In veterinary vaccinology, the oral route of administration is an attractive alternative compared to the commonly used parenteral route. Yeasts have a number of properties that make them potential live delivery systems for oral vaccination purposes such as their high expression levels, their GRAS status, adjuvant properties, and post-translational modification possibilities. Consequently, yeasts have been employed for the expression of heterologous genes and for the production of therapeutic proteins. Yeast-based vaccines are reviewed with regard to their ability to express and produce antigens from pathogens for veterinary use. Many of these vaccines have been shown to elicit protective immune responses following oral immunization in animals. Ultimately, yeast-based oral vaccines may offer a potential opportunity for the development of novel ideal vaccines in veterinary medicine. Copyright © 2013 Elsevier Ltd. All rights reserved.

  9. An Improved Bacterial-Foraging Optimization-Based Machine Learning Framework for Predicting the Severity of Somatization Disorder

    OpenAIRE

    Xinen Lv; Huiling Chen; Qian Zhang; Xujie Li; Hui Huang; Gang Wang

    2018-01-01

    It is of great clinical significance to establish an accurate intelligent model to diagnose the somatization disorder of community correctional personnel. In this study, a novel machine learning framework is proposed to predict the severity of somatization disorder in community correction personnel. The core of this framework is to adopt the improved bacterial foraging optimization (IBFO) to optimize two key parameters (penalty coefficient and the kernel width) of a kernel extreme learning ma...

  10. Breeding success of a marine central place forager in the context of climate change: A modeling approach.

    Directory of Open Access Journals (Sweden)

    Lauriane Massardier-Galatà

    Full Text Available In response to climate warming, a southward shift in productive frontal systems serving as the main foraging sites for many top predator species is likely to occur in Subantarctic areas. Central place foragers, such as seabirds and pinnipeds, are thus likely to cope with an increase in the distance between foraging locations and their land-based breeding colonies. Understanding how central place foragers should modify their foraging behavior in response to changes in prey accessibility appears crucial. A spatially explicit individual-based simulation model (Marine Central Place Forager Simulator (MarCPFS, including bio-energetic components, was built to evaluate effects of possible changes in prey resources accessibility on individual performances and breeding success. The study was calibrated on a particular example: the Antarctic fur seal (Arctocephalus gazella, which alternates between oceanic areas in which females feed and the land-based colony in which they suckle their young over a 120 days rearing period. Our model shows the importance of the distance covered to feed and prey aggregation which appeared to be key factors to which animals are highly sensitive. Memorization and learning abilities also appear to be essential breeding success traits. Females were found to be most successful for intermediate levels of prey aggregation and short distance to the resource, resulting in optimal female body length. Increased distance to resources due to climate warming should hinder pups' growth and survival while female body length should increase.

  11. Phonation behavior of cooperatively foraging spinner dolphins.

    Science.gov (United States)

    Benoit-Bird, Kelly J; Au, Whitlow W L

    2009-01-01

    Groups of spinner dolphins have been shown to cooperatively herd small prey. It was hypothesized that the strong group coordination is maintained by acoustic communication, specifically by frequency-modulated whistles. Observations of groups of spinner dolphins foraging at night within a sound-scattering layer were made with a multibeam echosounder while the rates of dolphin sounds were measured using four hydrophones at 6 m depth intervals. Whistles were only detected when dolphins were not foraging and when animals were surfacing. Differences in click rates were found between depths and between different foraging stages but were relatively low when observations indicated that dolphins were actively feeding despite the consistency of these clicks with echolocation signals. Highest click rates occurred within the scattering layer, during transitions between foraging states. This suggests that clicks may be used directly or indirectly to cue group movement during foraging, potentially by detecting other individuals' positions in the group or serving a direct communicative role which would be contrary to the existing assumption that echolocation and communication are compartmentalized. Communicating via clicks would be beneficial as the signal's characteristics minimize the chance of eavesdropping by competing dolphins and large fish. Our results are unable to support the established paradigm for dolphin acoustic communication and suggest an alternate coordination mechanism in foraging spinner dolphins.

  12. Habitat-specific foraging of prothonotary warblers: Deducing habitat quality

    Science.gov (United States)

    Lyons, J.E.

    2005-01-01

    Foraging behavior often reflects food availability in predictable ways. For example, in habitats where food availability is high, predators should attack prey more often and move more slowly than in habitats where food availability is low. To assess relative food availability and habitat quality, I studied the foraging behavior of breeding Prothonotary Warblers (Protonotaria citrea) in two forest habitat types, cypress-gum swamp forest and coastal-plain levee forest. I quantified foraging behavior with focal animal sampling and continuous recording during foraging bouts. I measured two aspects of foraging behavior: 1) prey attack rate (attacks per minute), using four attack maneuvers (glean, sally, hover, strike), and 2) foraging speed (movements per minute), using three types of movement (hop, short flight [???1 m], long flight [>1 m]). Warblers attacked prey more often in cypress-gum swamp forest than in coastal-plain levee forest. Foraging speed, however, was not different between habitats. I also measured foraging effort (% time spent foraging) and relative frequency of attack maneuvers employed in each habitat; neither of these variables was influenced by forest type. I conclude that Prothonotary Warblers encounter more prey when foraging in cypress-gum swamps than in coastal-plain levee forest, and that greater food availability results in higher density and greater reproductive success for birds breeding in cypress-gum swamp.

  13. FORBEEF: A Forage-Livestock System Computer Model Used as a Teaching Aid for Decision Making.

    Science.gov (United States)

    Stringer, W. C.; And Others

    1987-01-01

    Describes the development of a computer simulation model of forage-beef production systems, which is intended to incorporate soil, forage, and animal decisions into an enterprise scenario. Produces a summary of forage production and livestock needs. Cites positive assessment of the program's value by participants in inservice training workshops.…

  14. Systematic review of the influence of foraging habitat on red-cockaded woodpecker reproductive success

    Science.gov (United States)

    James E. Garabedian; Christopher E. Moorman; M. Nils Peterson; John C. Kilgo

    2014-01-01

    Relationships between foraging habitat and reproductive success provide compelling evidence of the contribution of specific vegetative features to foraging habitat quality, a potentially limiting factor for many animal populations. For example, foraging habitat quality likely will gain importance in the recovery of the threatened red-cockaded woodpecker Picoides...

  15. Resource utilization by foraging eastern red bats (Lasiurus borealis) in the Ozark Region of Missouri

    Science.gov (United States)

    Sybill K. Amelon; Frank R. III Thompson; Joshua J. Millspaugh

    2014-01-01

    Resource selection by animals influences ecological processes such as dispersal, reproduction, foraging, and migration. Little information exists regarding foraging resource selection by bats during the maternity season. We evaluated support for effects of landcover type, landform, and landscape pattern on resource selection by individual foraging female eastern red...

  16. 21 CFR 573.400 - Ethoxyquin in certain dehydrated forage crops.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Ethoxyquin in certain dehydrated forage crops. 573... DRINKING WATER OF ANIMALS Food Additive Listing § 573.400 Ethoxyquin in certain dehydrated forage crops. Ethoxyquin (1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline) may be safely used in the dehydrated forage crops...

  17. MULTI-TEMPORAL CROP SURFACE MODELS COMBINED WITH THE RGB VEGETATION INDEX FROM UAV-BASED IMAGES FOR FORAGE MONITORING IN GRASSLAND

    Directory of Open Access Journals (Sweden)

    M. Possoch

    2016-06-01

    Full Text Available Remote sensing of crop biomass is important in regard to precision agriculture, which aims to improve nutrient use efficiency and to develop better stress and disease management. In this study, multi-temporal crop surface models (CSMs were generated from UAV-based dense imaging in order to derive plant height distribution and to determine forage mass. The low-cost UAV-based RGB imaging was carried out in a grassland experiment at the University of Bonn, Germany, in summer 2015. The test site comprised three consecutive growths including six different nitrogen fertilizer levels and three replicates, in sum 324 plots with a size of 1.5×1.5 m. Each growth consisted of six harvesting dates. RGB-images and biomass samples were taken at twelve dates nearly biweekly within two growths between June and September 2015. Images were taken with a DJI Phantom 2 in combination of a 2D Zenmuse gimbal and a GoPro Hero 3 (black edition. Overlapping images were captured in 13 to 16 m and overview images in approximately 60 m height at 2 frames per second. The RGB vegetation index (RGBVI was calculated as the normalized difference of the squared green reflectance and the product of blue and red reflectance from the non-calibrated images. The post processing was done with Agisoft PhotoScan Professional (SfM-based and Esri ArcGIS. 14 ground control points (GCPs were located in the field, distinguished by 30 cm × 30 cm markers and measured with a RTK-GPS (HiPer Pro Topcon with 0.01 m horizontal and vertical precision. The errors of the spatial resolution in x-, y-, z-direction were in a scale of 3-4 cm. From each survey, also one distortion corrected image was georeferenced by the same GCPs and used for the RGBVI calculation. The results have been used to analyse and evaluate the relationship between estimated plant height derived with this low-cost UAV-system and forage mass. Results indicate that the plant height seems to be a suitable indicator for forage mass

  18. Multi-Temporal Crop Surface Models Combined with the RGB Vegetation Index from Uav-Based Images for Forage Monitoring in Grassland

    Science.gov (United States)

    Possoch, M.; Bieker, S.; Hoffmeister, D.; Bolten, A.; Schellberg, J.; Bareth, G.

    2016-06-01

    Remote sensing of crop biomass is important in regard to precision agriculture, which aims to improve nutrient use efficiency and to develop better stress and disease management. In this study, multi-temporal crop surface models (CSMs) were generated from UAV-based dense imaging in order to derive plant height distribution and to determine forage mass. The low-cost UAV-based RGB imaging was carried out in a grassland experiment at the University of Bonn, Germany, in summer 2015. The test site comprised three consecutive growths including six different nitrogen fertilizer levels and three replicates, in sum 324 plots with a size of 1.5×1.5 m. Each growth consisted of six harvesting dates. RGB-images and biomass samples were taken at twelve dates nearly biweekly within two growths between June and September 2015. Images were taken with a DJI Phantom 2 in combination of a 2D Zenmuse gimbal and a GoPro Hero 3 (black edition). Overlapping images were captured in 13 to 16 m and overview images in approximately 60 m height at 2 frames per second. The RGB vegetation index (RGBVI) was calculated as the normalized difference of the squared green reflectance and the product of blue and red reflectance from the non-calibrated images. The post processing was done with Agisoft PhotoScan Professional (SfM-based) and Esri ArcGIS. 14 ground control points (GCPs) were located in the field, distinguished by 30 cm × 30 cm markers and measured with a RTK-GPS (HiPer Pro Topcon) with 0.01 m horizontal and vertical precision. The errors of the spatial resolution in x-, y-, z-direction were in a scale of 3-4 cm. From each survey, also one distortion corrected image was georeferenced by the same GCPs and used for the RGBVI calculation. The results have been used to analyse and evaluate the relationship between estimated plant height derived with this low-cost UAV-system and forage mass. Results indicate that the plant height seems to be a suitable indicator for forage mass. There is a

  19. Scientific Opinion on the use of animal-based measures to assess welfare in pigs

    DEFF Research Database (Denmark)

    Broom, D.; Doherr, M.G.; Edwards, S.

    2013-01-01

    Animal-based measures, identified on the basis of scientific evidence, can be used effectively in the evaluation of the welfare of on-farm pigs in relation to laws, codes of practice, quality assurance schemes and management. Some of these measures are also appropriate for ante-mortem inspection...... and there are additional post-mortem animal-based measures which can be taken at the slaughterhouse. Non-animal-based measures can be used when the association between them and the welfare outcome is strong and when they are more efficient than animal-based measures as a means to safeguard welfare. Both animal......-based and non-animal-based measures can be useful predictors of welfare in pigs. In order to assess welfare, a wide range of measures is needed. However, to assess aspects of welfare it is unnecessary to use all animal-based measures on every occasion. The choice of animal-based measures will depend upon...

  20. Evolution of foraging behavior in Drosophilid larvae

    Science.gov (United States)

    Rivera-Alba, Marta; Kabra, Mayank; Branson, Kristin; Mirth, Christen

    2015-03-01

    Drosophilids, like other insects, go through a larval phase before metamorphosing into adults. Larvae increase their body weight by several orders of magnitude in a few days. We therefore hypothesized that foraging behavior is under strong evolutionary pressure to best fit the larval environment. To test our hypothesis we used a multidisciplinary approach to analyze foraging behavior across species and larval stages. First, we recorded several videos of larvae foraging for each of 47 Drosophilid species. Then, using a supervised machine learning approach, we automatically annotated the video collection for the foraging sub-behaviors, including crawling, turning, head casting or burrowing. We also computed over 100 features to describe the posture and dynamics of each animal in each video frame. From these data, we fit models to the behavior of each species. The models each had the same parametric form, but differed in the exact parameters. By simulating larva behavior in virtual arenas we can infer which properties of the environments are better for each species. Comparisons between these inferred environments and the actual environments where these animals live will give us a deeper understanding about the evolution of foraging behavior in Drosophilid larvae.

  1. Application of genomics to forage crop breeding for quality traits

    DEFF Research Database (Denmark)

    Lübberstedt, Thomas

    2007-01-01

    Forage quality depends on the digestibility of fodder, and can be directly measured by the intake and metabolic conversion in animal trials. However, animal trials are time-consuming, laborious, and thus expensive. It is not possible to study thousands of plant genotypes, as required in breeding...... selection ultimately without need of field trials, and being environment independent. In addition, once identified relevant genes controlling forage quality are targets for transgenic approaches. Substantial progress has recently been achieved in the development and application of genomic tools both...... studied in detail and sequence motifs with likely effect on forage quality have been identified by association studies. Moreover, transgenic approaches substantiated the effect of several of these genes on forage quality. Perspectives and limitations of these findings for forage crop breeding...

  2. Forage herbs improve mineral composition of grassland herbage

    DEFF Research Database (Denmark)

    Pirhofer-Walzl, Karin; Søegaard, Karen; Jensen, Henning Høgh

    2011-01-01

    Provision of an adequate mineral supply in the diets of ruminants fed mainly on grassland herbage can present a challenge if mineral concentrations are suboptimal for animal nutrition. Forage herbs may be included in grassland seed mixtures to improve herbage mineral content, although there is li......Provision of an adequate mineral supply in the diets of ruminants fed mainly on grassland herbage can present a challenge if mineral concentrations are suboptimal for animal nutrition. Forage herbs may be included in grassland seed mixtures to improve herbage mineral content, although...... there is limited information about mineral concentrations in forage herbs. To determine whether herbs have greater macro- and micromineral concentrations than forage legumes and grasses, we conducted a 2-year experiment on a loamy-sand site in Denmark sown with a multi-species mixture comprised of three functional......-poor grasses. Our study indicates that including herbs in forage mixtures is an effective way of increasing mineral concentrations in herbage....

  3. A synteny-based draft genome sequence of the forage grass Lolium perenne

    DEFF Research Database (Denmark)

    Byrne, Stephen; Nagy, Istvan; Pfeifer, Matthias

    2015-01-01

    Here we report the draft genome sequence of perennial ryegrass (Lolium perenne), an economically important forage and turf grass species that is widely cultivated in temperate regions worldwide. It is classified along with wheat, barley, oats and Brachypodium distachyon in the Pooideae sub...... the pistil of a plant to reject self-pollen and therefore promote out-crossing. We have used the sequence assembly to characterize transcriptional changes in the stigma during pollination with both compatible and incompatible pollen. Characterization of the pollen transcriptome identified homologs to pollen...

  4. Supplementation based on protein or energy ingredients to beef cattle consuming low-quality cool-season forages: II. Performance, reproductive, and metabolic responses of replacement heifers.

    Science.gov (United States)

    Cappellozza, B I; Cooke, R F; Reis, M M; Moriel, P; Keisler, D H; Bohnert, D W

    2014-06-01

    This experiment evaluated the influence of supplement composition on performance, reproductive, and metabolic responses of Angus × Hereford heifers consuming a low-quality cool-season forage (8.7% CP and 57% TDN). Sixty heifers (initial age = 226 ± 3 d) were allocated into 15 drylot pens (4 heifers/pen and 5 pens/treatment) and assigned to 1) supplementation with soybean meal (PROT), 2) supplementation with a mixture of cracked corn, soybean meal, and urea (68:22:10 ratio, DM basis; ENER), or 3) no supplementation (CON). Heifers were offered meadow foxtail (Alopecurus pratensis L.) hay for ad libitum consumption during the experiment (d -10 to 160). Beginning on d 0, PROT and ENER were provided daily at a rate of 1.30 and 1.40 kg of DM/heifer to ensure that PROT and ENER intakes were isocaloric and isonitrogenous. Hay and total DMI were recorded for 5 consecutive days during each month of the experiment. Blood was collected every 10 d for analysis of plasma progesterone to evaluate puberty attainment. Blood samples collected on d -10, 60, 120, and 150 were also analyzed for plasma concentrations of plasma urea N (PUN), glucose, insulin, IGF-I, NEFA, and leptin. Liver samples were collected on d 100 from 2 heifers/pen and analyzed for mRNA expression of genes associated with nutritional metabolism. No treatment effect was detected (P = 0.33) on forage DMI. Total DMI, ADG, and mean concentrations of glucose, insulin, and IGF-I as well as hepatic mRNA expression of IGF-I and IGFBP-3 were greater (P ≤ 0.02) for PROT and ENER compared with CON and similar between PROT and ENER (P ≥ 0.13). Mean PUN concentrations were also greater (P forage had a similar increase in DMI, growth, and overall metabolic status if offered supplements based on soybean meal or corn at 0.5% of BW.

  5. Animation-Based Learning in Geology: Impact of Animations Coupled with Seductive Details

    Science.gov (United States)

    Clayton, Rodney L.

    2016-01-01

    Research is not clear on how to address the difficulty students have conceptualizing geologic processes and phenomena. This study investigated how animations coupled with seductive details effect learners' situational interest and emotions. A quantitative quasi-experimental study employing an independent-measures factorial design was used. The…

  6. Effect of source of trace minerals in either forage- or by-product-based diets fed to dairy cows: 1. Production and macronutrient digestibility.

    Science.gov (United States)

    Faulkner, M J; Weiss, W P

    2017-07-01

    Excess rumen-soluble Cu and Zn can alter rumen microbial populations and reduce fiber digestibility. Because of differences in particle size and chemical composition, ruminal and total-tract digestibility of fiber from forage- and by-product-based diets can differ. We hypothesized that, because of differences in mineral solubility, diets with hydroxy rather than sulfate trace minerals would have greater fiber digestibility, but the effect may depend on source of fiber. Eighteen multiparous cows were used in a split-plot replicated Latin square with two 28-d periods to evaluate the effects of Cu, Zn, and Mn source (sulfates or hydroxy; Micronutrients USA LLC, Indianapolis, IN) and neutral detergent fiber (NDF) source (forage diet = 26% NDF vs. by-product = 36%) on total-tract nutrient digestibility. During the entire experiment (56 d) cows remained on the same fiber treatment, but source of supplemental trace mineral was different for each 28-d period so that all cows were exposed to both mineral treatments. During each of the two 28-d periods, cows were fed no supplemental Cu, Zn, or Mn for 16 d followed by 12 d of feeding supplemental Cu, Zn, and Mn from either sulfates or hydroxy sources. Supplemental minerals for each of the mineral sources fed provided approximately 10, 35, and 32 mg/kg of supplemental Cu, Zn, and Mn, respectively, for both fiber treatments. Total dietary concentrations of Cu, Zn, and Mn were approximately 19, 65, and 70 mg/kg for the forage diets and 21, 85, and 79 mg/kg for the by-product diets, respectively. Treatment had no effect on dry matter intake (24.2 kg/d) or milk production (34.9 kg/d). Milk fatty acid profiles were altered by fiber source, mineral source, and their interaction. Cows fed the by-product diets had lower dry matter (65.9 vs. 70.2%), organic matter (67.4 vs. 71.7%), and crude protein digestibility (58.8 vs. 62.1%) but greater starch (97.5 vs. 96.3%) and NDF digestibility (50.5 vs. 44.4%) compared with cows fed the

  7. Nitrous oxide emission factors for urine and dung from sheep fed either fresh forage rape (Brassica napus L.) or fresh perennial ryegrass (Lolium perenne L.).

    Science.gov (United States)

    Luo, J; Sun, X Z; Pacheco, D; Ledgard, S F; Lindsey, S B; Hoogendoorn, C J; Wise, B; Watkins, N L

    2015-03-01

    In New Zealand, agriculture is predominantly based on pastoral grazing systems and animal excreta deposited on soil during grazing have been identified as a major source of nitrous oxide (N2O) emissions. Forage brassicas (Brassica spp.) have been increasingly used to improve lamb performance. Compared with conventional forage perennial ryegrass (Lolium perenne L.), a common forage in New Zealand, forage brassicas have faster growth rates, higher dry matter production and higher nutritive value. The aim of this study was to determine the partitioning of dietary nitrogen (N) between urine and dung in the excreta from sheep fed forage brassica rape (B. napus subsp. oleifera L.) or ryegrass, and then to measure N2O emissions when the excreta from the two different feed sources were applied to a pasture soil. A sheep metabolism study was conducted to determine urine and dung-N outputs from sheep fed forage rape or ryegrass, and N partitioning between urine and dung. Urine and dung were collected and then used in a field plot experiment for measuring N2O emissions. The experimental site contained a perennial ryegrass/white clover pasture on a poorly drained silt-loam soil. The treatments included urine from sheep fed forage rape or ryegrass, dung from sheep fed forage rape or ryegrass, and a control without dung or urine applied. N2O emission measurements were carried out using a static chamber technique. For each excreta type, the total N2O emissions and emission factor (EF3; N2O-N emitted during the 3- or 8-month measurement period as a per cent of animal urine or dung-N applied, respectively) were calculated. Our results indicate that, in terms of per unit of N intake, a similar amount of N was excreted in urine from sheep fed either forage rape or ryegrass, but less dung N was excreted from sheep fed forage rape than ryegrass. The EF3 for urine from sheep fed forage rape was lower compared with urine from sheep fed ryegrass. This may have been because of plant

  8. Elephant grass as forage for ruminant animals

    OpenAIRE

    Rusdy, Muhammad

    2016-01-01

    The shortage of feed, particularly during the dry season is one of the major factor limiting productivity of livestock in the tropics. Napier or elephant grass (Pennisetum purpureum Schum.) shows a great potential to alleviate the problem because it is drought resistant and has high dry matter yield potential. As an attempt to generate information useful for improving the utilization of the grass, its potential and limitation are described. Its chemical composition and nutritive value as rela...

  9. Dutch survey pyrrolizidine alkaloids in animal forage

    NARCIS (Netherlands)

    Mulder, P.P.J.; Beumer, B.; Oosterink, J.E.; Jong, de J.

    2009-01-01

    Pyrrolizidine alkaloids (PAs) are secondary plant metabolites produced by a number of plants from the Asteraceae (Compositae), Boriginaceae and Fabaceae (Leguminosae) families. Many of these alkaloids have been shown to be highly toxic, causing hepatic veno-occlusive disease (VOD), liver cirrhosis

  10. Dutch survey pyrrolizidine alkaloids in animal forage

    OpenAIRE

    Mulder, P.P.J.; Beumer, B.; Oosterink, J.E.; Jong, de, J.

    2009-01-01

    Pyrrolizidine alkaloids (PAs) are secondary plant metabolites produced by a number of plants from the Asteraceae (Compositae), Boriginaceae and Fabaceae (Leguminosae) families. Many of these alkaloids have been shown to be highly toxic, causing hepatic veno-occlusive disease (VOD), liver cirrhosis and ultimately death. PAs may have also mutagenic and carcinogenic potential. Amongst livestock, cattle and horses are especially susceptible to the toxic effects of the PAs. Humans may also be at r...

  11. Kudu foraging behaviour: Influenced by animal density?

    NARCIS (Netherlands)

    Waal, van der C.

    2005-01-01

    In deciduous savanna a marked decline in browse availability characterises the late dry season and apparently regulates populations of large browser species such as kudu. The dry season utilisation patterns of two woody species, Acacia tortilis and Boscia albitrunca, in two comparable sites but

  12. MACRO NUTRIENTS UPTAKE OF FORAGE GRASSES AT DIFFERENT SALINITY STRESSES

    Directory of Open Access Journals (Sweden)

    F. Kusmiyati

    2014-10-01

    Full Text Available The high concentration of sodium chloride (NaCl in saline soils has negative effects on the growth ofmost plants. The experiment was designed to evaluate macro nutrient uptake (Nitrogen, Phosphorus andPotassium of forage grasses at different NaCl concentrations in growth media. The experiment wasconducted in a greenhouse at Forage Crops Laboratory of Animal Agriculture Faculty, Diponegoro University.Split plot design was used to arrange the experiment. The main plot was forage grasses (Elephant grass(Pennisetum purpureum and King grass (Pennisetum hybrida. The sub plot was NaCl concentrationin growth media (0, 150, and 300 mM. The nitrogen (N, phosphorus (P and potassium (K uptake in shootand root of plant were measured. The result indicated increasing NaCl concentration in growth mediasignificantly decreased the N, P and K uptake in root and shoot of the elephant grass and king grass. Thepercentage reduction percentage of N, P and K uptake at 150 mM and 300 mM were high in elephant grassand king grass. It can be concluded that based on nitrogen, phosphorus and potassium uptake, elephantgrass and king grass are not tolerant to strong and very strong saline soil.

  13. Optimal search behavior and classic foraging theory

    International Nuclear Information System (INIS)

    Bartumeus, F; Catalan, J

    2009-01-01

    Random walk methods and diffusion theory pervaded ecological sciences as methods to analyze and describe animal movement. Consequently, statistical physics was mostly seen as a toolbox rather than as a conceptual framework that could contribute to theory on evolutionary biology and ecology. However, the existence of mechanistic relationships and feedbacks between behavioral processes and statistical patterns of movement suggests that, beyond movement quantification, statistical physics may prove to be an adequate framework to understand animal behavior across scales from an ecological and evolutionary perspective. Recently developed random search theory has served to critically re-evaluate classic ecological questions on animal foraging. For instance, during the last few years, there has been a growing debate on whether search behavior can include traits that improve success by optimizing random (stochastic) searches. Here, we stress the need to bring together the general encounter problem within foraging theory, as a mean for making progress in the biological understanding of random searching. By sketching the assumptions of optimal foraging theory (OFT) and by summarizing recent results on random search strategies, we pinpoint ways to extend classic OFT, and integrate the study of search strategies and its main results into the more general theory of optimal foraging.

  14. Corn in consortium with forages

    Directory of Open Access Journals (Sweden)

    Cássia Maria de Paula Garcia

    2013-12-01

    Full Text Available The basic premises for sustainable agricultural development with focus on rural producers are reducing the costs of production and aggregation of values through the use crop-livestock system (CLS throughout the year. The CLS is based on the consortium of grain crops, especially corn with tropical forages, mainly of the genus Panicum and Urochloa. The study aimed to evaluate the grain yield of irrigated corn crop intercropped with forage of the genus Panicum and Urochloa. The experiment was conducted at the Fazenda de Ensino, Pesquisa e Extensão – FEPE  of the Faculdade de Engenharia - UNESP, Ilha Solteira in an Oxisol in savannah conditions and in the autumn winter of 2009. The experimental area was irrigated by a center pivot and had a history of no-tillage system for 8 years. The corn hybrid used was simple DKB 390 YG at distances of 0.90 m. The seeds of grasses were sown in 0.34 m spacing in the amount of 5 kg ha-1, they were mixed with fertilizer minutes before sowing  and placed in a compartment fertilizer seeder and fertilizers were mechanically deposited in the soil at a depth of 0.03 m. The experimental design used was a randomized block with four replications and five treatments: Panicum maximum cv. Tanzania sown during the nitrogen fertilization (CTD of the corn; Panicum maximum cv. Mombaça sown during the nitrogen fertilization (CMD of the corn; Urochloa brizantha cv. Xaraés sown during the occasion of nitrogen fertilization (CBD of the corn; Urochloa ruziziensis cv. Comumsown during the nitrogen fertilization (CRD of the corn and single corn (control. The production components of corn: plant population per hectare (PlPo, number of ears per hectare (NE ha-1, number of rows per ear (NRE, number of kernels per row on the cob (NKR, number of grain in the ear (NGE and mass of 100 grains (M100G were not influenced by consortium with forage. Comparing grain yield (GY single corn and maize intercropped with forage of the genus Panicum

  15. An energetics-based honeybee nectar-foraging model used to assess the potential for landscape-level pesticide exposure dilution.

    Science.gov (United States)

    Baveco, Johannes M; Focks, Andreas; Belgers, Dick; van der Steen, Jozef J M; Boesten, Jos J T I; Roessink, Ivo

    2016-01-01

    Estimating the exposure of honeybees to pesticides on a landscape scale requires models of their spatial foraging behaviour. For this purpose, we developed a mechanistic, energetics-based model for a single day of nectar foraging in complex landscape mosaics. Net energetic efficiency determined resource patch choice. In one version of the model a single optimal patch was selected each hour. In another version, recruitment of foragers was simulated and several patches could be exploited simultaneously. Resource availability changed during the day due to depletion and/or intrinsic properties of the resource (anthesis). The model accounted for the impact of patch distance and size, resource depletion and replenishment, competition with other nectar foragers, and seasonal and diurnal patterns in availability of nectar-providing crops and wild flowers. From the model we derived simple rules for resource patch selection, e.g., for landscapes with mass-flowering crops only, net energetic efficiency would be proportional to the ratio of the energetic content of the nectar divided by distance to the hive. We also determined maximum distances at which resources like oilseed rape and clover were still energetically attractive. We used the model to assess the potential for pesticide exposure dilution in landscapes of different composition and complexity. Dilution means a lower concentration in nectar arriving at the hive compared to the concentration in nectar at a treated field and can result from foraging effort being diverted away from treated fields. Applying the model for all possible hive locations over a large area, distributions of dilution factors were obtained that were characterised by their 90-percentile value. For an area for which detailed spatial data on crops and off-field semi-natural habitats were available, we tested three landscape management scenarios that were expected to lead to exposure dilution: providing alternative resources than the target crop

  16. An energetics-based honeybee nectar-foraging model used to assess the potential for landscape-level pesticide exposure dilution

    Directory of Open Access Journals (Sweden)

    Johannes M. Baveco

    2016-08-01

    Full Text Available Estimating the exposure of honeybees to pesticides on a landscape scale requires models of their spatial foraging behaviour. For this purpose, we developed a mechanistic, energetics-based model for a single day of nectar foraging in complex landscape mosaics. Net energetic efficiency determined resource patch choice. In one version of the model a single optimal patch was selected each hour. In another version, recruitment of foragers was simulated and several patches could be exploited simultaneously. Resource availability changed during the day due to depletion and/or intrinsic properties of the resource (anthesis. The model accounted for the impact of patch distance and size, resource depletion and replenishment, competition with other nectar foragers, and seasonal and diurnal patterns in availability of nectar-providing crops and wild flowers. From the model we derived simple rules for resource patch selection, e.g., for landscapes with mass-flowering crops only, net energetic efficiency would be proportional to the ratio of the energetic content of the nectar divided by distance to the hive. We also determined maximum distances at which resources like oilseed rape and clover were still energetically attractive. We used the model to assess the potential for pesticide exposure dilution in landscapes of different composition and complexity. Dilution means a lower concentration in nectar arriving at the hive compared to the concentration in nectar at a treated field and can result from foraging effort being diverted away from treated fields. Applying the model for all possible hive locations over a large area, distributions of dilution factors were obtained that were characterised by their 90-percentile value. For an area for which detailed spatial data on crops and off-field semi-natural habitats were available, we tested three landscape management scenarios that were expected to lead to exposure dilution: providing alternative resources than

  17. Ontogenetic and among-individual variation in foraging strategies of northeast Pacific white sharks based on stable isotope analysis

    Science.gov (United States)

    Kim, S.L.; Tinker, M. Tim; Estes, J.A.; Koch, P.L.

    2012-01-01

    There is growing evidence for individuality in dietary preferences and foraging behaviors within populations of various species. This is especially important for apex predators, since they can potentially have wide dietary niches and a large impact on trophic dynamics within ecosystems. We evaluate the diet of an apex predator, the white shark (Carcharodon carcharias), by measuring the stable carbon and nitrogen isotope composition of vertebral growth bands to create lifetime records for 15 individuals from California. Isotopic variations in white shark diets can reflect within-region differences among prey (most importantly related to trophic level), as well as differences in baseline values among the regions in which sharks forage, and both prey and habitat preferences may shift with age. The magnitude of isotopic variation among sharks in our study (>5‰ for both elements) is too great to be explained solely by geographic differences, and so must reflect differences in prey choice that may vary with sex, size, age and location. Ontogenetic patterns in δ15N values vary considerably among individuals, and one third of the population fit each of these descriptions: 1) δ15N values increased throughout life, 2) δ15N values increased to a plateau at ~5 years of age, and 3) δ15N values remained roughly constant values throughout life. Isotopic data for the population span more than one trophic level, and we offer a qualitative evaluation of diet using shark-specific collagen discrimination factors estimated from a 3+ year captive feeding experiment (Δ13Cshark-diet and Δ15Nshark-diet equal 4.2‰ and 2.5‰, respectively). We assess the degree of individuality with a proportional similarity index that distinguishes specialists and generalists. The isotopic variance is partitioned among differences between-individual (48%), within-individuals (40%), and by calendar year of sub-adulthood (12%). Our data reveal substantial ontogenetic and individual dietary

  18. Ontogenetic and among-individual variation in foraging strategies of northeast Pacific white sharks based on stable isotope analysis.

    Directory of Open Access Journals (Sweden)

    Sora L Kim

    Full Text Available There is growing evidence for individuality in dietary preferences and foraging behaviors within populations of various species. This is especially important for apex predators, since they can potentially have wide dietary niches and a large impact on trophic dynamics within ecosystems. We evaluate the diet of an apex predator, the white shark (Carcharodon carcharias, by measuring the stable carbon and nitrogen isotope composition of vertebral growth bands to create lifetime records for 15 individuals from California. Isotopic variations in white shark diets can reflect within-region differences among prey (most importantly related to trophic level, as well as differences in baseline values among the regions in which sharks forage, and both prey and habitat preferences may shift with age. The magnitude of isotopic variation among sharks in our study (>5‰ for both elements is too great to be explained solely by geographic differences, and so must reflect differences in prey choice that may vary with sex, size, age and location. Ontogenetic patterns in δ(15N values vary considerably among individuals, and one third of the population fit each of these descriptions: 1 δ(15N values increased throughout life, 2 δ(15N values increased to a plateau at ∼5 years of age, and 3 δ(15N values remained roughly constant values throughout life. Isotopic data for the population span more than one trophic level, and we offer a qualitative evaluation of diet using shark-specific collagen discrimination factors estimated from a 3+ year captive feeding experiment (Δ(13C(shark-diet and Δ(15N(shark-diet equal 4.2‰ and 2.5‰, respectively. We assess the degree of individuality with a proportional similarity index that distinguishes specialists and generalists. The isotopic variance is partitioned among differences between-individual (48%, within-individuals (40%, and by calendar year of sub-adulthood (12%. Our data reveal substantial ontogenetic and

  19. Empowering non-designers through animation-based sketching

    DEFF Research Database (Denmark)

    Luciani, Danwei; Vistisen, Peter

    2017-01-01

    This paper asks whether it is feasible and valuable to facilitate early stakeholder involvement in the design process by applying animation as a common temporal sketching language. We build on the notion of sketching as an efficient activity for designers to think with and communicate ideas through...... in the early concept exploration phase. We then discuss whether animation could be a suitable mediator of the sketching mind-set in stakeholders with varying preconditions for participating in the early exploratory phase of design....

  20. Foraging modality and plasticity in foraging traits determine the strength of competitive interactions among carnivorous plants, spiders and toads.

    Science.gov (United States)

    Jennings, David E; Krupa, James J; Rohr, Jason R

    2016-07-01

    Foraging modalities (e.g. passive, sit-and-wait, active) and traits are plastic in some species, but the extent to which this plasticity affects interspecific competition remains unclear. Using a long-term laboratory mesocosm experiment, we quantified competition strength and the plasticity of foraging traits in a guild of generalist predators of arthropods with a range of foraging modalities. Each mesocosm contained eight passively foraging pink sundews, and we employed an experimental design where treatments were the presence or absence of a sit-and-wait foraging spider and actively foraging toad crossed with five levels of prey abundance. We hypothesized that actively foraging toads would outcompete the other species at low prey abundance, but that spiders and sundews would exhibit plasticity in foraging traits to compensate for strong competition when prey were limited. Results generally supported our hypotheses. Toads had a greater effect on sundews at low prey abundances, and toad presence caused spiders to locate webs higher above the ground. Additionally, the closer large spider webs were to the ground, the greater the trichome densities produced by sundews. Also, spider webs were larger with than without toads and as sundew numbers increased, and these effects were more prominent as resources became limited. Finally, spiders negatively affected toad growth only at low prey abundance. These findings highlight the long-term importance of foraging modality and plasticity of foraging traits in determining the strength of competition within and across taxonomic kingdoms. Future research should assess whether plasticity in foraging traits helps to maintain coexistence within this guild and whether foraging modality can be used as a trait to reliably predict the strength of competitive interactions. © 2016 The Authors. Journal of Animal Ecology © 2016 British Ecological Society.

  1. Caroço de algodão em dietas à base de palma forrageira para vacas leiteiras: síntese de proteína microbiana Whole cottonseed in forage cactus based diets: synthesis of microbial protein

    Directory of Open Access Journals (Sweden)

    Airon Aparecido Silva de Melo

    2007-08-01

    Full Text Available Objetivou-se avaliar o efeito da inclusão de caroço de algodão em substituição parcial à silagem de sorgo e ao farelo de soja em dietas à base de palma forrageira sobre a produção de proteína microbiana, a eficiência de síntese de proteína microbiana e as concentrações de uréia na urina e de uréia e N-uréia no plasma e no leite de vacas holandesas em lactação. Foram utilizados cinco animais aos 50 dias de lactação, distribuídos em quadrado latino 5 × 5. Os tratamentos consistiram de cinco níveis (0,0; 6,25; 12,50; 18,75 e 25,00% de inclusão de caroço de algodão na MS da dieta. A inclusão de caroço de algodão na dieta não influenciou a síntese de nitrogênio ou proteína microbiana, cujos valores médios foram 295,08 e 1.844,27 g/dia, respectivamente. As eficiências de síntese de nitrogênio e proteína microbiana diminuíram linearmente, em proporções de 0,30 e 1,43 g para cada 1% de caroço de algodão na dieta, respectivamente. Os níveis de uréia na urina e de uréia e N-uréia no plasma e no leite não foram afetados pela inclusão de caroço de algodão na dieta. Portanto, em dietas à base de palma forrageira, a inclusão de caroço de algodão em níveis de até 25% da MS não interfere na síntese de proteína microbiana e nas concentrações de uréia.The objective of this trial was to investigate the effects of partial replacement of sorghum silage and soybean meal with whole cottonseed on microbial protein synthesis and efficiency and nitrogen metabolism in lactating Holstein cows receiving forage cactus based diets. Five animals were randomly assigned to a 5 × 5 Latin square design and were fed diets containing (% of DM: 0.0, 6.25, 12.50, 18.75, and 25.00% of whole cottonseed. Inclusion of whole cottonseed in the diet did not affect microbial nitrogen and microbial protein synthesis, which averaged 295.08 and 1844.27 g/day, respectively. Microbial protein synthesis and microbial nitrogen

  2. MR-based keyhole SPECT for small animal imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Keum Sil; Roeck, Werner W; Nalcioglu, Orhan [Tu and Yuen Center for Functional Onco-Imaging, University of California, Irvine, Irvine, CA (United States); Gullberg, Grant T, E-mail: keumsill@uci.edu [Department of Radiotracer Development and Imaging Technology, Ernest Orlando Lawrence Berkeley National Laboratory, Berkeley, CA (United States)

    2011-02-07

    The rationale for multi-modality imaging is to integrate the strengths of different imaging technologies while reducing the shortcomings of an individual modality. The work presented here proposes a limited-field-of-view (LFOV) SPECT reconstruction technique that can be implemented on a multi-modality MR/SPECT system that can be used to obtain simultaneous MRI and SPECT images for small animal imaging. The reason for using a combined MR/SPECT system in this work is to eliminate any possible misregistration between the two sets of images when MR images are used as a priori information for SPECT. In nuclear imaging the target area is usually smaller than the entire object; thus, focusing the detector on the LFOV results in various advantages including the use of a smaller nuclear detector (less cost), smaller reconstruction region (faster reconstruction) and higher spatial resolution when used in conjunction with pinhole collimators with magnification. The MR/SPECT system can be used to choose a region of interest (ROI) for SPECT. A priori information obtained by the full field-of-view (FOV) MRI combined with the preliminary SPECT image can be used to reduce the dimensions of the SPECT reconstruction by limiting the computation to the smaller FOV while reducing artifacts resulting from the truncated data. Since the technique is based on SPECT imaging within the LFOV it will be called the keyhole SPECT (K-SPECT) method. At first MRI images of the entire object using a larger FOV are obtained to determine the location of the ROI covering the target organ. Once the ROI is determined, the animal is moved inside the radiofrequency (rf) coil to bring the target area inside the LFOV and then simultaneous MRI and SPECT are performed. The spatial resolution of the SPECT image is improved by employing a pinhole collimator with magnification >1 by having carefully calculated acceptance angles for each pinhole to avoid multiplexing. In our design all the pinholes are focused to

  3. Increased Foraging in Outdoor Organic Pig Production-Modeling Environmental Consequences.

    Science.gov (United States)

    Jakobsen, Malene; Preda, Teodora; Kongsted, Anne Grete; Hermansen, John Erik

    2015-11-02

    Consumers' motivations for buying organic products include a wish of acquiring healthy, environmentally friendly products from production systems that also ensure a high level of animal welfare. However, the current Danish organic pig production faces important challenges regarding environmental impact of the system. High ammonia emissions arise from outdoor concrete areas with growing pigs and sows on pasture possess an increased risk of nitrogen (N) leaching. Direct foraging in the range area is suggested as a way to improve the nutrient efficiency at farm level and to support a more natural behavior of the pig. Thus, by modeling, we investigated the environmental consequences of two alternative scenarios with growing pigs foraging in the range area and different levels of crops available for foraging-grass-clover or a combination of Jerusalem artichokes and lucerne. It was possible to have growing pigs on free-range without increasing N leaching compared to the current practice. The alternative system with Jerusalem artichokes and lucerne (high integration of forage) showed the lowest carbon foot print with 3.12 CO₂ eq kg -1 live weight pig compared to the current Danish pasture based system with 3.69 kg CO₂ eq kg -1 live weight pig. Due to positive impact on soil carbon sequestration, the second alternative system based on grass-clover (low integration of forage) showed a similar carbon foot print compared to current practice with 3.68 kg CO₂ eq kg -1 live weight pig. It is concluded that in practice there is room for development of organic farming systems where direct foraging plays a central role.

  4. COMADRE - A global data base of animal demography

    DEFF Research Database (Denmark)

    Salguero-Gómez, Roberto; Jones, Owen R.; Archer, C. Ruth

    2016-01-01

    spanning the rich diversity of the animal kingdom world-wide. This information is fundamental to our understanding of the conditions that have shaped variation in animal life histories and their relationships with the environment, as well as the determinants of invasion and extinction. Matrix population...... Matrix Database, an open-data online repository, which in its version 1.0.0 contains data on 345 species world-wide, from 402 studies with a total of 1625 population projection matrices. COMADRE also contains ancillary information (e.g. ecoregion, taxonomy, biogeography, etc.) that facilitates...

  5. Reindeer (Rangifer tarandus and climate change: Importance of winter forage

    Directory of Open Access Journals (Sweden)

    Thrine Moen Heggberget

    2002-06-01

    Full Text Available As a consequence of increasing greenhouse gas concentrations, climate change is predicted to be particularly pronounced, although regionally variable, in the vast arctic, sub-arctic and alpine tundra areas of the northern hemisphere. Here, we review winter foraging conditions for reindeer and caribou (Rangifer tarandus living in these areas, and consider diet, forage quality and distribution, accessibility due to snow variation, and effects of snow condition on reindeer and caribou populations. Finally, we hypothesise how global warming may affect wild mountain reindeer herds in South Norway. Energy-rich lichens often dominate reindeer and caribou diets. The animals also prefer lichens, and their productivity has been shown to be higher on lichen-rich than on lichen-poor ranges. Nevertheless, this energy source appears to be neither sufficient as winter diet for reindeer or caribou (at least for pregnant females nor necessary. Some reindeer and caribou populations seem to be better adapted to a non-lichen winter diet, e.g. by a larger alimentary tract. Shrubs appear to be the most common alternative winter forage, while some grasses appear to represent a good, nutritionally-balanced winter diet. Reindeer/caribou make good use of a wide variety of plants in winter, including dead and dry parts that are digested more than expected based on their fibre content. The diversity of winter forage is probably important for the mineral content of the diet. A lichen-dominated winter diet may be deficient in essential dietary elements, e.g. minerals. Sodium in particular may be marginal in inland winter ranges. Our review indicates that most Rangifer populations with lichen-dominated winter diets are either periodically or continuously heavily harvested by humans or predators. However, when population size is mainly limited by food, accessible lichen resources are often depleted. Plant studies simulating climatic change indicate that a warmer, wetter

  6. African Web-Based Animal Health Information: Analysis Of Online ...

    African Journals Online (AJOL)

    This implies that the web is dominated with the information from developed world. The paper recommends that African scientists should utilize both open access repositories and journals to increase accessibility of the local animal health content on the web. University of Dar Es Salaam Library Journal Vol. 9 (1) 2007: pp.

  7. Context-Based Questions: Optics in Animal Eyes

    Science.gov (United States)

    Kaltakci, Derya; Eryilmaz, Ali

    2011-01-01

    Context is important as a motivational factor for student involvement with physics. The diversity in the types and the functions of animal eyes is an excellent context in which to achieve this goal. There exists a range of subtopics in optics including pinhole, reflection, refraction, and superposition that can be discussed in the context of the…

  8. Mathematical foundation of the optimization-based fluid animation method

    DEFF Research Database (Denmark)

    Erleben, Kenny; Misztal, Marek Krzysztof; Bærentzen, Jakob Andreas

    2011-01-01

    We present the mathematical foundation of a fluid animation method for unstructured meshes. Key contributions not previously treated are the extension to include diffusion forces and higher order terms of non-linear force approximations. In our discretization we apply a fractional step method...

  9. Ant Foraging As an Indicator of Tropical Dry Forest Restoration.

    Science.gov (United States)

    Hernández-Flores, J; Osorio-Beristain, M; Martínez-Garza, C

    2016-08-01

    Variation in foraging behavior may indicate differences in food availability and allow assessment of restoration actions. Ants are prominent bioindicators used in assessing ecological responses to disturbance. However, behavioral data have been poorly incorporated as an index. The foraging performance of red harvester ants was quantified in order to evaluate the success of a restoration ecology experiment in the tropical dry forest of Sierra de Huautla, Morelos, in central Mexico. Foraging performance by granivorous, Pogonomyrmex barbatus, ants was diminished after 6 and 8 years of cattle grazing and wood harvest were excluded as part of a restoration experiment in a highly degraded biome. Despite investing more time in foraging, ant colonies in exclusion plots showed lower foraging success and acquired less seed biomass than colonies in control plots. In line with the predictions of optimal foraging theory, in restored plots where ant foraging performance was poor, ants harvested a higher diversity of seeds. Reduced foraging success and increased harvest of non-preferred foods in exclusion plots were likely due to the growth of herbaceous vegetation, which impedes travel by foragers. Moreover, by 8 years of exclusion, 37% of nests in exclusion plots had disappeared compared to 0% of nests in control plots. Ants' foraging success and behavior were sensitive to changes in habitat quality due to the plant successional process triggered by a restoration intervention. This study spotlights on the utility of animal foraging behavior in the evaluation of habitat restoration programs. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Assessment of Competition between Fisheries and Steller Sea Lions in Alaska Based on Estimated Prey Biomass, Fisheries Removals and Predator Foraging Behaviour.

    Directory of Open Access Journals (Sweden)

    Tabitha C Y Hui

    Full Text Available A leading hypothesis to explain the dramatic decline of Steller sea lions (Eumetopias jubatus in western Alaska during the latter part of the 20th century is a change in prey availability due to commercial fisheries. We tested this hypothesis by exploring the relationships between sea lion population trends, fishery catches, and the prey biomass accessible to sea lions around 33 rookeries between 2000 and 2008. We focused on three commercially important species that have dominated the sea lion diet during the population decline: walleye pollock, Pacific cod and Atka mackerel. We estimated available prey biomass by removing fishery catches from predicted prey biomass distributions in the Aleutian Islands, Bering Sea and Gulf of Alaska; and modelled the likelihood of sea lions foraging at different distances from rookeries (accessibility using satellite telemetry locations of tracked animals. We combined this accessibility model with the prey distributions to estimate the prey biomass accessible to sea lions by rookery. For each rookery, we compared sea lion population change to accessible prey biomass. Of 304 comparisons, we found 3 statistically significant relationships, all suggesting that sea lion populations increased with increasing prey accessibility. Given that the majority of comparisons showed no significant effect, it seems unlikely that the availability of pollock, cod or Atka mackerel was limiting sea lion populations in the 2000s.

  11. Assessment of Competition between Fisheries and Steller Sea Lions in Alaska Based on Estimated Prey Biomass, Fisheries Removals and Predator Foraging Behaviour

    Science.gov (United States)

    Hui, Tabitha C. Y.; Gryba, Rowenna; Gregr, Edward J.; Trites, Andrew W.

    2015-01-01

    A leading hypothesis to explain the dramatic decline of Steller sea lions (Eumetopias jubatus) in western Alaska during the latter part of the 20th century is a change in prey availability due to commercial fisheries. We tested this hypothesis by exploring the relationships between sea lion population trends, fishery catches, and the prey biomass accessible to sea lions around 33 rookeries between 2000 and 2008. We focused on three commercially important species that have dominated the sea lion diet during the population decline: walleye pollock, Pacific cod and Atka mackerel. We estimated available prey biomass by removing fishery catches from predicted prey biomass distributions in the Aleutian Islands, Bering Sea and Gulf of Alaska; and modelled the likelihood of sea lions foraging at different distances from rookeries (accessibility) using satellite telemetry locations of tracked animals. We combined this accessibility model with the prey distributions to estimate the prey biomass accessible to sea lions by rookery. For each rookery, we compared sea lion population change to accessible prey biomass. Of 304 comparisons, we found 3 statistically significant relationships, all suggesting that sea lion populations increased with increasing prey accessibility. Given that the majority of comparisons showed no significant effect, it seems unlikely that the availability of pollock, cod or Atka mackerel was limiting sea lion populations in the 2000s. PMID:25950178

  12. Industry and Consumers Awareness for Effective Management of Functional Animal-based Foods in South Korea

    OpenAIRE

    Wi, Seo-Hyun; Park, Jung-Min; Wee, Sung-Hwan; Park, Jae-Woo; Kim, Jin-Man

    2013-01-01

    In recent years, manufacturers of animal-based foods with health claims have encountered difficulties in the labeling of their products because of a lack of regulation on defining the functionality of animal-based foods. Therefore, this study was conducted to establish the basic requirements for the development of a definition for functional animal-based foods by investigating consumer and industry awareness. Survey data were collected from 114 industry representatives and 1,100 consumers. Th...

  13. Place-based differences in the commission of recurrent animal cruelty.

    Science.gov (United States)

    Tallichet, Suzanne E; Hensley, Christopher; Evans, Rhea A

    2012-12-01

    Despite the recent surge in research linking animal and human acts of violence, relatively few studies have been conducted examining animal cruelty itself. Although several researchers have begun to identify some of the correlates of animal cruelty, few have attempted to understand how differences in the backgrounds of rural and urban residents have led to their abuse of animals. Using survey data from 180 inmates, this study examines how demographic characteristics, exposure to animal cruelty in childhood, and the target animal's relationship with the abuser have contributed to the frequency of acts of animal cruelty in urban- and rural-based settings. Unlike their urban counterparts, rural respondents who engaged in recurrent animal cruelty were more likely to have witnessed family members and/or friends abuse an animal. Moreover, rural respondents who engaged in recurrent animal cruelty abused pet and stray animals, whereas recurrent animal abusers who grew up in urban areas tended to abuse pets only. These findings suggest possible place-based differences in the etiology of recurrent animal cruelty.

  14. The spatial distribution of flocking foragers : disentangling the effects of food availability, interference and conspecific attraction by means of spatial autoregressive modeling

    NARCIS (Netherlands)

    Folmer, Eelke O.; Olff, Han; Piersma, Theunis; Robinson, Rob

    Patch choice of foraging animals is typically assumed to depend positively on food availability and negatively on interference while benefits of the co-occurrence of conspecifics tend to be ignored. In this paper we integrate a classical functional response model based on resource availability and

  15. Computer-Aided Evaluation of Forage Management: Forage Manager.

    Science.gov (United States)

    Panciera, M. T.; And Others

    1993-01-01

    Presents the Forage Manager spreadsheet, developed as a forage management teaching tool to integrate agronomic, livestock, and cost data to demonstrate the impact of forage management on livestock production costs. Teaching applications, examples involving agronomic data and conventional agronomic evaluation, and limitations of the program are…

  16. Foraging plasticity by a keystone excavator, the white-headed woodpecker, in managed forests: Are there consequences for productivity?

    Science.gov (United States)

    Teresa J. Lorenz; Kerri T. Vierling; Jeffrey M. Kozma; Janet E. Millard

    2016-01-01

    Information on the foraging ecology of animals is important for conservation and management, particularly for keystone species whose presence affects ecosystem health. We examined foraging by an at-risk cavity excavator, the white-headed woodpecker (Picoides albolarvatus). The foraging needs of this species are used to inform management of...

  17. Redesigning forages with condensed tannins

    Science.gov (United States)

    Maximizing protein content in forages and minimizing protein loss during silage fermentation and rumen digestion are concerns for livestock and dairy producers. Substantial amounts of forage protein undergo proteolysis (breakdown) during the ensiling process and during rumen fermentation, transforme...

  18. Representing the acquisition and use of energy by individuals in agent-based models of animal populations

    Science.gov (United States)

    Sibly, Richard M.; Grimm, Volker; Martin, Benjamin T.; Johnston, Alice S.A.; Kulakowska, Katarzyna; Topping, Christopher J.; Calow, Peter; Nabe-Nielsen, Jacob; Thorbek, Pernille; DeAngelis, Donald L.

    2013-01-01

    1. Agent-based models (ABMs) are widely used to predict how populations respond to changing environments. As the availability of food varies in space and time, individuals should have their own energy budgets, but there is no consensus as to how these should be modelled. Here, we use knowledge of physiological ecology to identify major issues confronting the modeller and to make recommendations about how energy budgets for use in ABMs should be constructed. 2. Our proposal is that modelled animals forage as necessary to supply their energy needs for maintenance, growth and reproduction. If there is sufficient energy intake, an animal allocates the energy obtained in the order: maintenance, growth, reproduction, energy storage, until its energy stores reach an optimal level. If there is a shortfall, the priorities for maintenance and growth/reproduction remain the same until reserves fall to a critical threshold below which all are allocated to maintenance. Rates of ingestion and allocation depend on body mass and temperature. We make suggestions for how each of these processes should be modelled mathematically. 3. Mortality rates vary with body mass and temperature according to known relationships, and these can be used to obtain estimates of background mortality rate. 4. If parameter values cannot be obtained directly, then values may provisionally be obtained by parameter borrowing, pattern-oriented modelling, artificial evolution or from allometric equations. 5. The development of ABMs incorporating individual energy budgets is essential for realistic modelling of populations affected by food availability. Such ABMs are already being used to guide conservation planning of nature reserves and shell fisheries, to assess environmental impacts of building proposals including wind farms and highways and to assess the effects on nontarget organisms of chemicals for the control of agricultural pests.

  19. Bacteria-foraging based-control of high-performance railway level-crossing safety drives fed from photovoltaic array

    Directory of Open Access Journals (Sweden)

    Essamudin A. Ebrahim

    2016-12-01

    Full Text Available In the past ten years, railway level-crossing accidents have noticeably escalated in an indisputably preposterous manner, this devastating snag opened the floodgates for the frustrating death of a numerous number of the third world’s citizens, especially in Egypt. To tackle with this problem, a fully intelligent control system is required, which must be automated without human intervention. So, in this research, a new proposed level-crossing tracking system is designed and introduced. The system comprises a high-performance induction motor (IM fed from photovoltaic (PV array, the boom barrier (gate with its mechanism – as a load – buck–boost converter, inverter, and two smart PI-controllers. The first one is designed to regulate the duty cycle of the converter to its optimum value required to balance between maximum power point tracking (MPPT and keeping dc-link voltage of the inverter at a minimum level needed to maintain the motor internal torque at rated value. The second PI-controller is designed for speed control of indirect field-oriented vector-control (IFO-VC IM. The proposed design problems of MPPT, dc-link voltage and speed controllers are solved as optimization problems by bacteria-foraging optimization (BFO algorithm to search for the optimal PI-parameters. The simulation test results are acquired when using the battery-less PV-array with and without the proposed controllers. Also, results are obtained when applying several prescribed speed trajectories to test the robustness against PV-irradiance fluctuations and motor-dynamic disturbances. From these results, the proposed intelligent controllers are robust compared to classical Ziegler–Nichols (ZN PI-controllers and also when the motor is directly fed from PV generator without converter.

  20. Sistemas de alimentação para a recria de ovinos a pasto: avaliação do desempenho animal e características da forragem Feeding systems for sheep rearing on pasture: evaluation of animal performance and forage characteristics

    Directory of Open Access Journals (Sweden)

    Marcos da Silva Brum

    2008-02-01

    presented average values of forage mass higher than other treatments, due to the great amount of dead material in the available forage. MP presented larger ratio of leaves in relation to NG and ING. The average stocking rate of 914kg of LW ha-1 of MP was superior to 261kg of LW ha-1 and 467kg of LW ha-1 of NG and ING, respectively. Average daily liveweight gain (DLG in treatment MP (0.151kg day-1 was superior to NG (0.053kg day-1 and ING (0.058kg day-1, providing larger final live weight (36kg of LW animal-1 and final body score (3.7 units in MP. Larger crude protein values and smaller of FDA and FDN was observed in MP in relation to NG and ING. The final volume of gas, the degradation rates and time of colonization were well correlated to the chemical composition and the weight gain accurately observed, being better for MP. Even in situations of adverse climatic conditions, millet pasture demonstrated to be a good alternative to increase the stocking rate and the weight gain in sheep rearing systems in Rio Grande do Sul.

  1. Mercury contamination and stable isotopes reveal variability in foraging ecology of generalist California gulls

    Science.gov (United States)

    Peterson, Sarah; Ackerman, Joshua T.; Eagles-Smith, Collin A.

    2017-01-01

    Environmental contaminants are a concern for animal health, but contaminant exposure can also be used as a tracer of foraging ecology. In particular, mercury (Hg) concentrations are highly variable among aquatic and terrestrial food webs as a result of habitat- and site-specific biogeochemical processes that produce the bioaccumulative form, methylmercury (MeHg). We used stable isotopes and total Hg (THg) concentrations of a generalist consumer, the California gull (Larus californicus), to examine foraging ecology and illustrate the utility of using Hg contamination as an ecological tracer under certain conditions. We identified four main foraging clusters of gulls during pre-breeding and breeding, using a traditional approach based on light stable isotopes. The foraging cluster with the highest δ15N and δ34S values in gulls (cluster 4) had mean blood THg concentrations 614% (pre-breeding) and 250% (breeding) higher than gulls with the lowest isotope values (cluster 1). Using a traditional approach of stable-isotope mixing models, we showed that breeding birds with a higher proportion of garbage in their diet (cluster 2: 63–82% garbage) corresponded to lower THg concentrations and lower δ15N and δ34S values. In contrast, gull clusters with higher THg concentrations, which were more enriched in 15N and 34S isotopes, consumed a higher proportion of more natural, estuarine prey. δ34S values, which change markedly across the terrestrial to marine habitat gradient, were positively correlated with blood THg concentrations in gulls. The linkage we observed between stable isotopes and THg concentrations suggests that Hg contamination can be used as an additional tool for understanding animal foraging across coastal habitat gradients.

  2. Monitoring digestibility of forages for herbivores: a new application for an old approach

    Science.gov (United States)

    Vansomeren, Lindsey L.; Barboza, Perry S.; Thompson, Daniel P.; Gustine, David D.

    2015-01-01

    Ruminant populations are often limited by how well individuals are able to acquire nutrients for growth, maintenance, and reproduction. Nutrient supply to the animal is dictated by the concentration of nutrients in feeds and the efficiency of digesting those nutrients (i.e., digestibility). Many different methods have been used to measure digestibility of forages for wild herbivores, all of which rely on collecting rumen fluid from animals or incubation within animals. Animal-based methods can provide useful estimates, but the approach is limited by the expense of fistulated animals, wide variation in digestibility among animals, and contamination from endogenous and microbial sources that impairs the estimation of nutrient digestibility. We tested an in vitro method using a two-stage procedure using purified enzymes. The first stage, a 6 h acid–pepsin treatment, was followed by a combined 72 h amylase–cellulase or amylase–Viscozyme treatment. We then validated our estimates using in sacco and in vivo methods to digest samples of the same forages. In vitro estimates of dry matter (DM) digestibility were correlated with estimates of in sacco and in vivo DM digestibility (both P < 0.01). The in vitro procedure using Viscozyme (r2 = 0.77) was more precise than the in vitro procedure using cellulase (r2 = 0.59). Both procedures can be used to predict in sacco digestibility after correcting for the biases of each method. We used the in vitro method to measure digestibility of nitrogen (N; 0.07–0.95 g/g), which declined to zero as total N content declined below 0.03–0.06 g/g of DM. The in vitro method is well suited to monitoring forage quality over multiple years because it is reproducible, can be used with minimal investment by other laboratories without animal facilities, and can measure digestibility of individual nutrients such as N.

  3. Foraging modes of cordyliform lizards

    African Journals Online (AJOL)

    1996-05-27

    May 27, 1996 ... Perry's. (I995) criterion of < 10 PlM for ambush foraging is used here. Although lizard foraging behaviour clusters in two dis- crete modes (McLaughlin 1989). MPM and PTM vary sub- stantially within modes. Here we report the first quantitative data on foraging behav- iour in cordyliform lizards. MPM and PlM ...

  4. The application of foraging theory to the information searching behaviour of general practitioners.

    Science.gov (United States)

    Dwairy, Mai; Dowell, Anthony C; Stahl, Jean-Claude

    2011-08-23

    General Practitioners (GPs) employ strategies to identify and retrieve medical evidence for clinical decision making which take workload and time constraints into account. Optimal Foraging Theory (OFT) initially developed to study animal foraging for food is used to explore the information searching behaviour of General Practitioners. This study is the first to apply foraging theory within this context.Study objectives were: 1. To identify the sequence and steps deployed in identifiying and retrieving evidence for clinical decision making. 2. To utilise Optimal Foraging Theory to assess the effectiveness and efficiency of General Practitioner information searching. GPs from the Wellington region of New Zealand were asked to document in a pre-formatted logbook the steps and outcomes of an information search linked to their clinical decision making, and fill in a questionnaire about their personal, practice and information-searching backgrounds. A total of 115/155 eligible GPs returned a background questionnaire, and 71 completed their information search logbook. GPs spent an average of 17.7 minutes addressing their search for clinical information. Their preferred information sources were discussions with colleagues (38% of sources) and books (22%). These were the two most profitable information foraging sources (15.9 min and 9.5 min search time per answer, compared to 34.3 minutes in databases). GPs nearly always accessed another source when unsuccessful (95% after 1st source), and frequently when successful (43% after 2nd source). Use of multiple sources accounted for 41% of searches, and increased search success from 70% to 89%. By consulting in foraging terms the most 'profitable' sources of information (colleagues, books), rapidly switching sources when unsuccessful, and frequently double checking, GPs achieve an efficient trade-off between maximizing search success and information reliability, and minimizing searching time. As predicted by foraging theory, GPs

  5. The application of foraging theory to the information searching behaviour of general practitioners

    Directory of Open Access Journals (Sweden)

    Dowell Anthony C

    2011-08-01

    Full Text Available Abstract Background General Practitioners (GPs employ strategies to identify and retrieve medical evidence for clinical decision making which take workload and time constraints into account. Optimal Foraging Theory (OFT initially developed to study animal foraging for food is used to explore the information searching behaviour of General Practitioners. This study is the first to apply foraging theory within this context. Study objectives were: 1. To identify the sequence and steps deployed in identifiying and retrieving evidence for clinical decision making. 2. To utilise Optimal Foraging Theory to assess the effectiveness and efficiency of General Practitioner information searching. Methods GPs from the Wellington region of New Zealand were asked to document in a pre-formatted logbook the steps and outcomes of an information search linked to their clinical decision making, and fill in a questionnaire about their personal, practice and information-searching backgrounds. Results A total of 115/155 eligible GPs returned a background questionnaire, and 71 completed their information search logbook. GPs spent an average of 17.7 minutes addressing their search for clinical information. Their preferred information sources were discussions with colleagues (38% of sources and books (22%. These were the two most profitable information foraging sources (15.9 min and 9.5 min search time per answer, compared to 34.3 minutes in databases. GPs nearly always accessed another source when unsuccessful (95% after 1st source, and frequently when successful (43% after 2nd source. Use of multiple sources accounted for 41% of searches, and increased search success from 70% to 89%. Conclusions By consulting in foraging terms the most 'profitable' sources of information (colleagues, books, rapidly switching sources when unsuccessful, and frequently double checking, GPs achieve an efficient trade-off between maximizing search success and information reliability, and

  6. Short Communication A self-limiting complete feed changes forage ...

    African Journals Online (AJOL)

    A self-limiting complete feed changes forage intake and animal performance of growing meat goats. B. Payne. 1,2†. , J. Crenwelge. 1,2. , B.D. Lambert. 1,2# and J.P. Muir. 1. 1 Texas Agricultural Experiment Station, Stephenville, TX 76401, USA. 2 Tarleton State University, Department of Animal Sciences, Box T-0070, ...

  7. Foraging parameters influencing the detection and interpretation of area-restricted search behaviour in marine predators: a case study with the masked booby.

    Directory of Open Access Journals (Sweden)

    Julia Sommerfeld

    Full Text Available Identification of Area-restricted search (ARS behaviour is used to better understand foraging movements and strategies of marine predators. Track-based descriptive analyses are commonly used to detect ARS behaviour, but they may be biased by factors such as foraging trip duration or non-foraging behaviours (i.e. resting on the water. Using first-passage time analysis we tested if (I daylight resting at the sea surface positions falsely increase the detection of ARS behaviour and (II short foraging trips are less likely to include ARS behaviour in Masked Boobies Sula dactylatra. We further analysed whether ARS behaviour may be used as a proxy to identify important feeding areas. Depth-acceleration and GPS-loggers were simultaneously deployed on chick-rearing adults to obtain (1 location data every 4 minutes and (2 detailed foraging activity such as diving rates, time spent sitting on the water surface and in flight. In 82% of 50 foraging trips, birds adopted ARS behaviour. In 19.3% of 57 detected ARS zones, birds spent more than 70% of total ARS duration resting on the water, suggesting that these ARS zones were falsely detected. Based on generalized linear mixed models, the probability of detecting false ARS zones was 80%. False ARS zones mostly occurred during short trips in close proximity to the colony, with low or no diving activity. This demonstrates the need to account for resting on the water surface positions in marine animals when determining ARS behaviour based on foraging locations. Dive rates were positively correlated with trip duration and the probability of ARS behaviour increased with increasing number of dives, suggesting that the adoption of ARS behaviour in Masked Boobies is linked to enhanced foraging activity. We conclude that ARS behaviour may be used as a proxy to identify important feeding areas in this species.

  8. Comportamento ingestivo de equinos e a relação com o aproveitamento das forragens e bem-estar dos animais Equine feeding behavior and its relation with forage use and animal welfare

    Directory of Open Access Journals (Sweden)

    João Ricardo Dittrich

    2010-07-01

    Full Text Available A sociedade está em novo direcionamento no qual se busca maior respeito nas relações com os animais, tanto na criação e utilização como alimento quanto para outras finalidades, como companhia, esportes, trabalho, entre outros. A domesticação e utilização dos equinos pelo homem proporcionaram a esta espécie inadequado manejo alimentar, principalmente pelo restrito conhecimento do comportamento ingestivo. As pastagens são, reconhecidamente, o ambiente adequado para a alimentação dos cavalos, mas é um sistema complexo que influencia as decisões dos animais em pastejo. O entendimento dos padrões comportamentais dos eqüinos é uma importante ferramenta para o manejo alimentar adequado. O dossel forrageiro é heterogêneo e a estrutura das plantas, como altura, densidade e componentes como folha, colmo e inflorescência, é explorada pelos cavalos por meio da seletividade, a qual permite ao cavalo a ingestão de nutrientes necessários à manutenção e desenvolvimento. Os dois principais fatores limitantes à seletividade são, na maioria das vezes, a oferta de forragem e o tempo de pastejo, resultantes do modelo utilizado na criação e manutenção dos equinos para diversas finalidades. As forragens, além de fontes de nutrientes, são importantes também na prevenção dos problemas clínicos e de desvios comportamentais. O incremento das pesquisas na utilização das pastagens, certamente, mostrará a importante relação entre os cavalos e o meio ambiente e direcionará para práticas de manejo mais adequadas à utilização e melhor qualidade de vida dos cavalos.The society has taken a new direction towards a respectable relationship with the animals and a more conscious breeding, use for food, sports and company. The domestication and the use of horses by people have caused wrong feeding management, which is mainly due to reduced knowledge on feeding behavior. The pastures are the appropriate environment to horses feeding

  9. Thermal and digestive constraints to foraging behaviour in marine mammals.

    Science.gov (United States)

    Rosen, David A S; Winship, Arliss J; Hoopes, Lisa A

    2007-11-29

    While foraging models of terrestrial mammals are concerned primarily with optimizing time/energy budgets, models of foraging behaviour in marine mammals have been primarily concerned with physiological constraints. This has historically centred on calculations of aerobic dive limits. However, other physiological limits are key to forming foraging behaviour, including digestive limitations to food intake and thermoregulation. The ability of an animal to consume sufficient prey to meet its energy requirements is partly determined by its ability to acquire prey (limited by available foraging time, diving capabilities and thermoregulatory costs) and process that prey (limited by maximum digestion capacity and the time devoted to digestion). Failure to consume sufficient prey will have feedback effects on foraging, thermoregulation and digestive capacity through several interacting avenues. Energy deficits will be met through catabolism of tissues, principally the hypodermal lipid layer. Depletion of this blubber layer can affect both buoyancy and gait, increasing the costs and decreasing the efficiency of subsequent foraging attempts. Depletion of the insulative blubber layer may also increase thermoregulatory costs, which will decrease the foraging abilities through higher metabolic overheads. Thus, an energy deficit may lead to a downward spiral of increased tissue catabolism to pay for increased energy costs. Conversely, the heat generated through digestion and foraging activity may help to offset thermoregulatory costs. Finally, the circulatory demands of diving, thermoregulation and digestion may be mutually incompatible. This may force animals to alter time budgets to balance these exclusive demands. Analysis of these interacting processes will lead to a greater understanding of the physiological constraints within which the foraging behaviour must operate.

  10. Effect of Nitrogen Rate on Quantitative and Qualitative Forage Yield of Maize, Pearl Millet and Sorghum in Double Cropping System

    Directory of Open Access Journals (Sweden)

    sh Khalesro

    2012-02-01

    Full Text Available Abstract In order to compare three summer forage grasses including sorghum (Sorghum bicolor cv. Speedfeed, corn (Zea mayz S.C. 704 and pearl millet (Pennisetum americanum cv. Nutrifeed for green chop forage production in double cropping system, a field experiment was conducted at research field of Tarbiat Modares University on 2006 growing season. Treatments were arranged in a split- plot design based on randomized complete blocks with four replications. In this research three forage crops as main factor and nitrogen rates (100, 200 and 300 kg N. ha-1 from the urea source as the sub- plot were studied. Results showed the positive response of crops to nitrogen increment, in such a manner that millet with 300 kg N ha-1 produced 85.8 t ha-1 fresh forage (%20.3 more than sorghum and %30.9 more than corn. Regarding to the sustainable agriculture objects, millet and sorghum with 200 kg N ha-1could be suggested. Forage yield advantages of millet and sorghum to corn was %10 and %12 respectively. They produce 72.4 and 73.5 t ha-1 fresh forage under this treatment. Finally regarding to general advantages of sorghum and millet to corn, especially in unsuitable condition like as drought and poor soil fertility, it seems that changing the corn with sorghum or pearl millet could be an appropriate option. Also decision making for recommending one of sorghum and millet need to more information like qualitative attributes in details and determining animal feeding indices (voluntary intake using in vivo methods. Keywords: Sorghum, Pearl millet, Corn, Nitrogen, Forage, Organic matter, Crud protein

  11. Evaluating oat cultivars for dairy forage production in the central ...

    African Journals Online (AJOL)

    The two most preferred cultivars by the farmers were Conway and Glamis. Based on DM and CP production, and farmers' choice, we conclude that Conway and Glamis stand a high chance of improving forage production in the area and other similar systems. Keywords: agronomy, Avena sativa, forage quality, livestock ...

  12. Potential for sorghum forages for dairy heifers in the midwest

    Science.gov (United States)

    Dairy heifers have lower dietary energy needs than lactating cows (63-65% TDN for 6-12 month old heifers; 58-60% TDN for >12 month old heifers), but forage-based diets containing significant amounts of corn silage often exceed the needs of pregnant heifers. Use of low-energy forages to decrease ener...

  13. Nuisance ecology: do scavenging condors exact foraging costs on pumas in Patagonia?

    Science.gov (United States)

    Elbroch, L Mark; Wittmer, Heiko U

    2013-01-01

    Predation risk describes the energetic cost an animal suffers when making a trade off between maximizing energy intake and minimizing threats to its survival. We tested whether Andean condors (Vultur gryphus) influenced the foraging behaviors of a top predator in Patagonia, the puma (Puma concolor), in ways comparable to direct risks of predation for prey to address three questions: 1) Do condors exact a foraging cost on pumas?; 2) If so, do pumas exhibit behaviors indicative of these risks?; and 3) Do pumas display predictable behaviors associated with prey species foraging in risky environments? Using GPS location data, we located 433 kill sites of 9 pumas and quantified their kill rates. Based upon time pumas spent at a carcass, we quantified handling time. Pumas abandoned >10% of edible meat at 133 of 266 large carcasses after a single night, and did so most often in open grasslands where their carcasses were easily detected by condors. Our data suggested that condors exacted foraging costs on pumas by significantly decreasing puma handling times at carcasses, and that pumas increased their kill rates by 50% relative to those reported for North America to compensate for these losses. Finally, we determined that the relative risks of detection and associated harassment by condors, rather than prey densities, explained puma "giving up times" (GUTs) across structurally variable risk classes in the study area, and that, like many prey species, pumas disproportionately hunted in high-risk, high-resource reward areas.

  14. Nuisance ecology: do scavenging condors exact foraging costs on pumas in Patagonia?

    Directory of Open Access Journals (Sweden)

    L Mark Elbroch

    Full Text Available Predation risk describes the energetic cost an animal suffers when making a trade off between maximizing energy intake and minimizing threats to its survival. We tested whether Andean condors (Vultur gryphus influenced the foraging behaviors of a top predator in Patagonia, the puma (Puma concolor, in ways comparable to direct risks of predation for prey to address three questions: 1 Do condors exact a foraging cost on pumas?; 2 If so, do pumas exhibit behaviors indicative of these risks?; and 3 Do pumas display predictable behaviors associated with prey species foraging in risky environments? Using GPS location data, we located 433 kill sites of 9 pumas and quantified their kill rates. Based upon time pumas spent at a carcass, we quantified handling time. Pumas abandoned >10% of edible meat at 133 of 266 large carcasses after a single night, and did so most often in open grasslands where their carcasses were easily detected by condors. Our data suggested that condors exacted foraging costs on pumas by significantly decreasing puma handling times at carcasses, and that pumas increased their kill rates by 50% relative to those reported for North America to compensate for these losses. Finally, we determined that the relative risks of detection and associated harassment by condors, rather than prey densities, explained puma "giving up times" (GUTs across structurally variable risk classes in the study area, and that, like many prey species, pumas disproportionately hunted in high-risk, high-resource reward areas.

  15. Foraging segregation and genetic divergence between geographically proximate colonies of a highly mobile seabird

    Science.gov (United States)

    Wiley, Anne E.; Welch, Andreanna J.; Ostrom, P.H.; James, Helen F.; Stricker, C.A.; Fleischer, R.C.; Gandhi, H.; Adams, J.; Ainley, D.G.; Duvall, F.; Holmes, N.; Hu, D.; Judge, S.; Penniman, J.; Swindle, K.A.

    2012-01-01

    Foraging segregation may play an important role in the maintenance of animal diversity, and is a proposed mechanism for promoting genetic divergence within seabird species. However, little information exists regarding its presence among seabird populations. We investigated genetic and foraging divergence between two colonies of endangered Hawaiian petrels (Pterodroma sandwichensis) nesting on the islands of Hawaii and Kauai using the mitochondrial Cytochrome b gene and carbon, nitrogen and hydrogen isotope values (?? 13C, ?? 15N and ??D, respectively) of feathers. Genetic analyses revealed strong differentiation between colonies on Hawaii and Kauai, with ?? ST = 0. 50 (p of birds from Kauai had significantly lower ?? 13C and ?? 15N values than those from Hawaii. This is consistent with Kauai birds provisioning chicks with prey derived from near or north of the Hawaiian Islands, and Hawaii birds provisioning young with prey from regions of the equatorial Pacific characterized by elevated ?? 15N values at the food web base. ?? 15N values of Kauai and Hawaii adults differed significantly, indicating additional foraging segregation during molt. Feather ??D varied from -69 to 53???. This variation cannot be related solely to an isotopically homogeneous ocean water source or evaporative water loss. Instead, we propose the involvement of salt gland excretion. Our data demonstrate the presence of foraging segregation between proximately nesting seabird populations, despite high species mobility. This ecological diversity may facilitate population coexistence, and its preservation should be a focus of conservation strategies. ?? 2011 Springer-Verlag (outside the USA).

  16. Age-related variation in foraging behaviour in the wandering albatross at South Georgia: no evidence for senescence.

    Science.gov (United States)

    Froy, Hannah; Lewis, Sue; Catry, Paulo; Bishop, Charles M; Forster, Isaac P; Fukuda, Akira; Higuchi, Hiroyoshi; Phalan, Ben; Xavier, Jose C; Nussey, Daniel H; Phillips, Richard A

    2015-01-01

    Age-related variation in demographic rates is now widely documented in wild vertebrate systems, and has significant consequences for population and evolutionary dynamics. However, the mechanisms underpinning such variation, particularly in later life, are less well understood. Foraging efficiency is a key determinant of fitness, with implications for individual life history trade-offs. A variety of faculties known to decline in old age, such as muscular function and visual acuity, are likely to influence foraging performance. We examine age-related variation in the foraging behaviour of a long-lived, wide-ranging oceanic seabird, the wandering albatross Diomedea exulans. Using miniaturised tracking technologies, we compared foraging trip characteristics of birds breeding at Bird Island, South Georgia. Based on movement and immersion data collected during the incubation phase of a single breeding season, and from extensive tracking data collected in previous years from different stages of the breeding cycle, we found limited evidence for age-related variation in commonly reported trip parameters, and failed to detect signs of senescent decline. Our results contrast with the limited number of past studies that have examined foraging behaviour in later life, since these have documented changes in performance consistent with senescence. This highlights the importance of studies across different wild animal populations to gain a broader perspective on the processes driving variation in ageing rates.

  17. Age-related variation in foraging behaviour in the wandering albatross at South Georgia: no evidence for senescence.

    Directory of Open Access Journals (Sweden)

    Hannah Froy

    Full Text Available Age-related variation in demographic rates is now widely documented in wild vertebrate systems, and has significant consequences for population and evolutionary dynamics. However, the mechanisms underpinning such variation, particularly in later life, are less well understood. Foraging efficiency is a key determinant of fitness, with implications for individual life history trade-offs. A variety of faculties known to decline in old age, such as muscular function and visual acuity, are likely to influence foraging performance. We examine age-related variation in the foraging behaviour of a long-lived, wide-ranging oceanic seabird, the wandering albatross Diomedea exulans. Using miniaturised tracking technologies, we compared foraging trip characteristics of birds breeding at Bird Island, South Georgia. Based on movement and immersion data collected during the incubation phase of a single breeding season, and from extensive tracking data collected in previous years from different stages of the breeding cycle, we found limited evidence for age-related variation in commonly reported trip parameters, and failed to detect signs of senescent decline. Our results contrast with the limited number of past studies that have examined foraging behaviour in later life, since these have documented changes in performance consistent with senescence. This highlights the importance of studies across different wild animal populations to gain a broader perspective on the processes driving variation in ageing rates.

  18. Modelling Pasture-based Automatic Milking System Herds: System Fitness of Grazeable Home-grown Forages, Land Areas and Walking Distances

    Directory of Open Access Journals (Sweden)

    M. R. Islam

    2015-06-01

    Full Text Available To maintain a predominantly pasture-based system, the large herd milked by automatic milking rotary would be required to walk significant distances. Walking distances of greater than 1-km are associated with an increased incidence of undesirably long milking intervals and reduced milk yield. Complementary forages can be incorporated into pasture-based systems to lift total home grown feed in a given area, thus potentially ‘concentrating’ feed closer to the dairy. The aim of this modelling study was to investigate the total land area required and associated walking distance for large automatic milking system (AMS herds when incorporating complementary forage rotations (CFR into the system. Thirty-six scenarios consisting of 3 AMS herds (400, 600, 800 cows, 2 levels of pasture utilisation (current AMS utilisation of 15.0 t dry matter [DM]/ha, termed as moderate; optimum pasture utilisation of 19.7 t DM/ha, termed as high and 6 rates of replacement of each of these pastures by grazeable CFR (0%, 10%, 20%, 30%, 40%, 50% were investigated. Results showed that AMS cows were required to walk greater than 1-km when the farm area was greater than 86 ha. Insufficient pasture could be produced within a 1 km distance (i.e. 86 ha land with home-grown feed (HGF providing 43%, 29%, and 22% of the metabolisable energy (ME required by 400, 600, and 800 cows, respectively from pastures. Introduction of pasture (moderate: CFR in AMS at a ratio of 80:20 can feed a 400 cow AMS herd, and can supply 42% and 31% of the ME requirements for 600 and 800 cows, respectively with pasture (moderate: CFR at 50:50 levels. In contrast to moderate pasture, 400 cows can be managed on high pasture utilisation (provided 57% of the total ME requirements. However, similar to the scenarios conducted with moderate pasture, there was insufficient feed produced within 1-km distance of the dairy for 600 or 800 cows. An 800 cow herd required 140 and 130 ha on moderate and high pasture-based

  19. Modelling Pasture-based Automatic Milking System Herds: System Fitness of Grazeable Home-grown Forages, Land Areas and Walking Distances.

    Science.gov (United States)

    Islam, M R; Garcia, S C; Clark, C E F; Kerrisk, K L

    2015-06-01

    To maintain a predominantly pasture-based system, the large herd milked by automatic milking rotary would be required to walk significant distances. Walking distances of greater than 1-km are associated with an increased incidence of undesirably long milking intervals and reduced milk yield. Complementary forages can be incorporated into pasture-based systems to lift total home grown feed in a given area, thus potentially 'concentrating' feed closer to the dairy. The aim of this modelling study was to investigate the total land area required and associated walking distance for large automatic milking system (AMS) herds when incorporating complementary forage rotations (CFR) into the system. Thirty-six scenarios consisting of 3 AMS herds (400, 600, 800 cows), 2 levels of pasture utilisation (current AMS utilisation of 15.0 t dry matter [DM]/ha, termed as moderate; optimum pasture utilisation of 19.7 t DM/ha, termed as high) and 6 rates of replacement of each of these pastures by grazeable CFR (0%, 10%, 20%, 30%, 40%, 50%) were investigated. Results showed that AMS cows were required to walk greater than 1-km when the farm area was greater than 86 ha. Insufficient pasture could be produced within a 1 km distance (i.e. 86 ha land) with home-grown feed (HGF) providing 43%, 29%, and 22% of the metabolisable energy (ME) required by 400, 600, and 800 cows, respectively from pastures. Introduction of pasture (moderate): CFR in AMS at a ratio of 80:20 can feed a 400 cow AMS herd, and can supply 42% and 31% of the ME requirements for 600 and 800 cows, respectively with pasture (moderate): CFR at 50:50 levels. In contrast to moderate pasture, 400 cows can be managed on high pasture utilisation (provided 57% of the total ME requirements). However, similar to the scenarios conducted with moderate pasture, there was insufficient feed produced within 1-km distance of the dairy for 600 or 800 cows. An 800 cow herd required 140 and 130 ha on moderate and high pasture-based AMS

  20. Forage yield and grazing efficiency on rotationally stocked pastures of 'Tanzania-1' guineagrass and 'Guaçu' elephantgrass

    Directory of Open Access Journals (Sweden)

    Pedreira Carlos Guilherme Silveira

    2005-01-01

    Full Text Available The potential carrying capacity of tropical pastures depends not only on the productivity of the forage species and the amount of forage on offer, but also on the efficiency with which the produced herbage is harvested by the grazing animal. This study was conducted to assess the yield and grazing efficiency on 'Guaçu' elephantgrass (Pennisetum purpureum Schum. and 'Tanzania-1' guineagrass (Panicum maximum Jacq. pastures under rotational stocking. Forage accumulation, daily accumulation rates, grazing losses, bulk density, and utilization efficiency were measured. Treatments (forages were replicated four times in a completely randomized design. Total forage dry matter (DM yield over 214 days of grazing were 23850 and 15000 kg ha-1, for the elephantgrass and the guineagrass, respectively, using 250 kg N ha-1 in split applications after each grazing. Mean forage accumulation per grazing cycle was 7950 and 5010 kg ha-1 and mean daily accumulation rates were 137 and 86 kg-1 ha-1 d-1 for P. purpureum and P. maximum, respectively. Grazing losses per cycle averaged 1040 and 880 kg ha-1, for grazing efficiencies of 52 and 37% for the Pennisetum and the Panicum, respectively. Mean seasonal stocking rate was 5.1 AU (animal unit = 500 kg LW per ha on P. purpureum and 3 AU ha-1 on P. maximum pastures. For both species, productivity potential resides on the high pasture carrying capacity, particularly when there are no soil fertility limitations during the warm/rainy season. Based on growth potential and stem elongation characteristics, 'Guaçu' requires better management skills and 'Tanzania-1' has a more pronounced seasonal growth, as expressed by seasonal yields, apparently due to their contrasting responses to temperature and daylength.

  1. Orbital Trajectory Simulation on Twin Stars System in Ifs Fractal Model Based on Hybrid Animation Method

    OpenAIRE

    Darmanto, Tedjo; Suwardi, Iping Supriana; Munir, Rinaldi

    2015-01-01

    IFS (Iterated Function Systems) is a method to model fractal object based on affine transformation functions. The star-like object rotation effect in the IFS fractal model could be exhibited by using metamorphical method, as a replacement to the affine rotation method on a non metamorphic animation. The advantage of a metamorphic animation method over the metamorphic animation method is that the object's relative position to the fixed point as an absolute centroid is absolute. Therefore, the ...

  2. Moving Evidence into Practice: Cost Analysis and Assessment of Macaques’ Sustained Behavioral Engagement with Videogames and Foraging Devices

    Science.gov (United States)

    Bennett, Allyson J.; Perkins, Chaney M.; Tenpas, Parker D.; Reinebach, Alma L.; Pierre, Peter J.

    2017-01-01

    Environmental enrichment plans for captive nonhuman primates often include provision of foraging devices. The rationale for using foraging devices is to promote species-typical activity patterns that encourage physical engagement and provide multi-sensory stimulation. However, these devices have been shown to be ineffective at sustaining manipulation over long periods of time, and often produce minimal cognitive engagement. Here we use an evidence-based approach to directly compare the amount of object-directed behavior with a foraging device and a computer-based videogame system. We recorded 11adult male rhesus monkeys’ interactions with a foraging device and two tasks within a joystick videogame cognitive test battery. Both techniques successfully produced high levels of engagement during the initial 20-min of observation. After 1-hr the monkeys manipulated the foraging device significantly less than the joystick, F(2,10)= 43.93, p videogame play for the majority of a 5-hr period, provided that they received a 94mg chow pellet upon successful completion of trials. Using a model approach we developed previously as a basis for standardized cost:benefit analysis to inform facility decisions, we calculated the comprehensive cost of incorporating a videogame system as an enrichment strategy. The videogame system has a higher initial cost compared to widely-used foraging devices however, the ongoing labor and supply costs are relatively low. Our findings add to two decades of empirical studies by a number of laboratories that have demonstrated the successful use of videogame-based systems to promote sustained non-social cognitive engagement for macaques. The broader significance of the work lies in the application of a systematic approach to compare and contrast enrichment strategies and encourage evidence-based decision making when choosing an enrichment strategy in a manner that promotes meaningful cognitive enrichment to the animals. PMID:27404766

  3. Moving evidence into practice: cost analysis and assessment of macaques' sustained behavioral engagement with videogames and foraging devices.

    Science.gov (United States)

    Bennett, Allyson J; Perkins, Chaney M; Tenpas, Parker D; Reinebach, Alma L; Pierre, Peter J

    2016-12-01

    Environmental enrichment plans for captive nonhuman primates often include provision of foraging devices. The rationale for using foraging devices is to promote species-typical activity patterns that encourage physical engagement and provide multi-sensory stimulation. However, these devices have been shown to be ineffective at sustaining manipulation over long periods of time, and often produce minimal cognitive engagement. Here we use an evidence-based approach to directly compare the amount of object-directed behavior with a foraging device and a computer-based videogame system. We recorded 11 adult male rhesus monkeys' interactions with a foraging device and two tasks within a joystick videogame cognitive test battery. Both techniques successfully produced high levels of engagement during the initial 20 min of observation. After 1 hr the monkeys manipulated the foraging device significantly less than the joystick, F(2,10) = 43.93, P videogame play for the majority of a 5 hr period, provided that they received a 94 mg chow pellet upon successful completion of trials. Using a model approach, we developed previously as a basis for standardized cost:benefit analysis to inform facility decisions, we calculated the comprehensive cost of incorporating a videogame system as an enrichment strategy. The videogame system has a higher initial cost compared to widely-used foraging devices, however, the ongoing labor and supply costs are relatively low. Our findings add to two decades of empirical studies by a number of laboratories that have demonstrated the successful use of videogame-based systems to promote sustained non-social cognitive engagement for macaques. The broader significance of the work lies in the application of a systematic approach to compare and contrast enrichment strategies and encourage evidence-based decision making when choosing an enrichment strategy in a manner that promotes meaningful cognitive enrichment to the animals. © 2016 Wiley

  4. ASSESSMENT OF THE DEVELOPMЕNT OF POND FORAGE BASE WHEN REARING CARP (CYPRINUS CARPIO CARPIO FISH SEEDS AT FISH FARM «MERKURIY»

    Directory of Open Access Journals (Sweden)

    B. Grishin

    2015-09-01

    Full Text Available Purpose. To assess the development of main components of natural forage base in nursery ponds during the period of rearing the carp fish seeds in monoculture. Methodology. Hydrobiological (bacterioplankton, phytoplankton, zooplankton, zoobenthos and hydrochemical samples have been collected and processes according to generally accepted methods. Findings. Qualitative and quantitative parameters of the development of bacterio-, phyto-, zooplankton and zoobenthos in nursery ponds have been studied when rearing young-of-the-year Lubin few scale carp, Antoninsko-Zozulenets carp and their reciprocal crosses in monoculture (50 thousand fish/ha. General water mineralization in ponds was 292.7–315.7 mg/dm3 and according to O.A. Alekin’s classification, pond water belonged to hydrocarbonate class of calcium group. Water pH was 7.4–7.5. Permanganate values were 12.5–14.9 mgO/dm3. On average, average ammonium nitrogen content, nitrite nitrogen and nitrate nitrogen, mineral phosphorus, total iron did not exceed normative values. Qualitative and quantitative parameters of phyto-, bacterio-, zooplankton of nursery ponds have been studied. The seasonal development of phytoplankton was within 15.96–20.88 mg/dm3 with the predominance of Chlorococcales in the floristic spectrum. The development of bacterioplankton was within 5.08–5.81 mg/dm3. Zooplankton was dominated by cladoceran-copepod complex with average seasonal values of 5.27–17.20 g/m3. Zoobenthos was formed of Diptera larvae (Chironomidae and Chaoboridae with average seasonal biomasses of 0.51–1.8 g/m2. According to saprobic parameters, pond water belonged to β-mesosabrobic zone and corresponded to the water quality class II (“clean enough” category. Fish productivity of nursery ponds was within 617.2–815.2 kg/ha; output of carp young-of-the-year was within 39.82–43.56%, mean weight of young-of-the-year was 31.0–39.3 g. Originality. For the first time we carried out a

  5. Personality, foraging and fitness consequences in a long lived seabird.

    Directory of Open Access Journals (Sweden)

    Samantha C Patrick

    Full Text Available While personality differences in animals are defined as consistent behavioural variation between individuals, the widely studied field of foraging specialisation in marine vertebrates has rarely been addressed within this framework. However there is much overlap between the two fields, both aiming to measure the causes and consequences of consistent individual behaviour. Here for the first time we use both a classic measure of personality, the response to a novel object, and an estimate of foraging strategy, derived from GPS data, to examine individual personality differences in black browed albatross and their consequences for fitness. First, we examine the repeatability of personality scores and link these to variation in foraging habitat. Bolder individuals forage nearer the colony, in shallower regions, whereas shyer birds travel further from the colony, and fed in deeper oceanic waters. Interestingly, neither personality score predicted a bird's overlap with fisheries. Second, we show that both personality scores are correlated with fitness consequences, dependent on sex and year quality. Our data suggest that shyer males and bolder females have higher fitness, but the strength of this relationship depends on year quality. Females who forage further from the colony have higher breeding success in poor quality years, whereas males foraging close to the colony always have higher fitness. Together these results highlight the potential importance of personality variation in seabirds and that the fitness consequences of boldness and foraging strategy may be highly sex dependent.

  6. Production and transcriptional regulation of proanthocyanidin biosynthesis in forage legumes.

    Science.gov (United States)

    Zhou, Meiliang; Wei, Li; Sun, Zhanmin; Gao, Lihua; Meng, Yu; Tang, Yixiong; Wu, Yanmin

    2015-05-01

    Proanthocyanidins (PA), also known as condensed tannins, contribute to important forage legumes traits including disease resistance and forage quality. PA in forage plants has both positive and negative effects on feed digestibility and animal performance. The analytical methods and their applicability in measuring the contents of PA in forage plants are essential to studies on their nutritional effects. In spite of important breakthroughs in our understanding of the PA biosynthesis, important questions still remain to be answered such as the PA polymerization and transport. Recent advances in the understanding of transcription factor-mediated gene regulation mechanisms in anthocyanin and PA biosynthetic pathway in model plants suggest new approaches for the metabolic engineering of PA in forage plants. The present review will attempt to present the state-of-the-art of research in these areas and provide an update on the production and metabolic engineering of PA in forage plants. We hope that this will contribute to a better understanding of the ways in which PA production to manipulate the content of PA for beneficial effects in forage plants.

  7. Dietary composition and spatial patterns of polar bear foraging on land in western Hudson Bay.

    Science.gov (United States)

    Gormezano, Linda J; Rockwell, Robert F

    2013-12-21

    Flexible foraging strategies, such as prey switching, omnivory and food mixing, are key to surviving in a labile and changing environment. Polar bears (Ursus maritimus) in western Hudson Bay are versatile predators that use all of these strategies as they seasonally exploit resources across trophic levels. Climate warming is reducing availability of their ice habitat, especially in spring when polar bears gain most of their annual fat reserves by consuming seal pups before coming ashore in summer. How polar bears combine these flexible foraging strategies to obtain and utilize terrestrial food will become increasingly important in compensating for energy deficits from lost seal hunting opportunities. We evaluated patterns in the composition of foods in scat to characterize the foraging behaviors that underpin the diet mixing and omnivory observed in polar bears on land in western Hudson Bay. Specifically, we measured diet richness, proportions of plant and animal foods, patterns in co-occurrence of foods, spatial composition and an index of temporal composition. Scats contained between 1 and 6 foods, with an average of 2.11 (SE = 0.04). Most scats (84.9%) contained at least one type of plant, but animals (35.4% of scats) and both plants and animals occurring together (34.4% of scats) were also common. Certain foods, such as Lyme grass seed heads (Leymus arenarius), berries and marine algae, were consumed in relatively higher proportions, sometimes to the exclusion of others, both where and when they occurred most abundantly. The predominance of localized vegetation in scats suggests little movement among habitat types between feeding sessions. Unlike the case for plants, no spatial patterns were found for animal remains, likely due the animals' more vagile and ubiquitous distribution. Our results suggest that polar bears are foraging opportunistically in a manner consistent with maximizing intake while minimizing energy expenditure associated with movement. The

  8. Drivers, challenges and opportunities of forage technology adoption by smallholder cattle households in Cambodia.

    Science.gov (United States)

    Ashley, K; Wilson, S; Young, J R; Chan, H P; Vitou, S; Suon, S; Windsor, P A; Bush, R D

    2018-01-01

    Forage technology has been successfully introduced into smallholder cattle systems in Cambodia as an alternative feed source to the traditional rice straw and native pastures, improving animal nutrition and reducing labour requirements of feeding cattle. Previous research has highlighted the positive impacts of forage technology including improved growth rates of cattle and household time savings. However, further research is required to understand the drivers, challenges and opportunities of forage technology for smallholder cattle households in Cambodia to facilitate widespread adoption and identify areas for further improvement. A survey of forage-growing households (n = 40) in July-September 2016 examined forage technology adoption experiences, including reasons for forage establishment, use of inputs and labour requirements of forage plot maintenance and use of forages (feeding, fattening, sale of grass or seedlings and silage). Time savings was reported as the main driver of forage adoption with household members spending approximately 1 h per day maintaining forages and feeding it to cattle. Water availability was reported as the main challenge to this activity. A small number of households also reported lack of labour, lack of fencing, competition from natural grasses, cost of irrigation and lack of experience as challenges to forage growing. Cattle fattening and sale of cut forage grass and seedlings was not found to be a widespread activity by interviewed households, with 25 and 10% of households reporting use of forages for these activities, respectively. Currently, opportunities exist for these households to better utilise forages through expansion of forage plots and cattle activities, although assistance is required to support these households in addressing current constraints, particularly availability of water, if the sustainability of this feed technology for smallholder cattle household is to be established in Cambodia.

  9. Fragmentation of nest and foraging habitat affects time budgets of solitary bees, their fitness and pollination services, depending on traits: Results from an individual-based model.

    Science.gov (United States)

    Everaars, Jeroen; Settele, Josef; Dormann, Carsten F

    2018-01-01

    Solitary bees are important but declining wild pollinators. During daily foraging in agricultural landscapes, they encounter a mosaic of patches with nest and foraging habitat and unsuitable matrix. It is insufficiently clear how spatial allocation of nesting and foraging resources and foraging traits of bees affect their daily foraging performance. We investigated potential brood cell construction (as proxy of fitness), number of visited flowers, foraging habitat visitation and foraging distance (pollination proxies) with the model SOLBEE (simulating pollen transport by solitary bees, tested and validated in an earlier study), for landscapes varying in landscape fragmentation and spatial allocation of nesting and foraging resources. Simulated bees varied in body size and nesting preference. We aimed to understand effects of landscape fragmentation and bee traits on bee fitness and the pollination services bees provide, as well as interactions between them, and the general consequences it has to our understanding of the system. This broad scope gives multiple key results. 1) Body size determines fitness more than landscape fragmentation, with large bees building fewer brood cells. High pollen requirements for large bees and the related high time budgets for visiting many flowers may not compensate for faster flight speeds and short handling times on flowers, giving them overall a disadvantage compared to small bees. 2) Nest preference does affect distribution of bees over the landscape, with cavity-nesting bees being restricted to nesting along field edges, which inevitably leads to performance reductions. Fragmentation mitigates this for cavity-nesting bees through increased edge habitat. 3) Landscape fragmentation alone had a relatively small effect on all responses. Instead, the local ratio of nest to foraging habitat affected bee fitness positively through reduced local competition. The spatial coverage of pollination increases steeply in response to this ratio

  10. Fragmentation of nest and foraging habitat affects time budgets of solitary bees, their fitness and pollination services, depending on traits: Results from an individual-based model

    Science.gov (United States)

    Settele, Josef; Dormann, Carsten F.

    2018-01-01

    Solitary bees are important but declining wild pollinators. During daily foraging in agricultural landscapes, they encounter a mosaic of patches with nest and foraging habitat and unsuitable matrix. It is insufficiently clear how spatial allocation of nesting and foraging resources and foraging traits of bees affect their daily foraging performance. We investigated potential brood cell construction (as proxy of fitness), number of visited flowers, foraging habitat visitation and foraging distance (pollination proxies) with the model SOLBEE (simulating pollen transport by solitary bees, tested and validated in an earlier study), for landscapes varying in landscape fragmentation and spatial allocation of nesting and foraging resources. Simulated bees varied in body size and nesting preference. We aimed to understand effects of landscape fragmentation and bee traits on bee fitness and the pollination services bees provide, as well as interactions between them, and the general consequences it has to our understanding of the system. This broad scope gives multiple key results. 1) Body size determines fitness more than landscape fragmentation, with large bees building fewer brood cells. High pollen requirements for large bees and the related high time budgets for visiting many flowers may not compensate for faster flight speeds and short handling times on flowers, giving them overall a disadvantage compared to small bees. 2) Nest preference does affect distribution of bees over the landscape, with cavity-nesting bees being restricted to nesting along field edges, which inevitably leads to performance reductions. Fragmentation mitigates this for cavity-nesting bees through increased edge habitat. 3) Landscape fragmentation alone had a relatively small effect on all responses. Instead, the local ratio of nest to foraging habitat affected bee fitness positively through reduced local competition. The spatial coverage of pollination increases steeply in response to this ratio

  11. Fragmentation of nest and foraging habitat affects time budgets of solitary bees, their fitness and pollination services, depending on traits: Results from an individual-based model.

    Directory of Open Access Journals (Sweden)

    Jeroen Everaars

    Full Text Available Solitary bees are important but declining wild pollinators. During daily foraging in agricultural landscapes, they encounter a mosaic of patches with nest and foraging habitat and unsuitable matrix. It is insufficiently clear how spatial allocation of nesting and foraging resources and foraging traits of bees affect their daily foraging performance. We investigated potential brood cell construction (as proxy of fitness, number of visited flowers, foraging habitat visitation and foraging distance (pollination proxies with the model SOLBEE (simulating pollen transport by solitary bees, tested and validated in an earlier study, for landscapes varying in landscape fragmentation and spatial allocation of nesting and foraging resources. Simulated bees varied in body size and nesting preference. We aimed to understand effects of landscape fragmentation and bee traits on bee fitness and the pollination services bees provide, as well as interactions between them, and the general consequences it has to our understanding of the system. This broad scope gives multiple key results. 1 Body size determines fitness more than landscape fragmentation, with large bees building fewer brood cells. High pollen requirements for large bees and the related high time budgets for visiting many flowers may not compensate for faster flight speeds and short handling times on flowers, giving them overall a disadvantage compared to small bees. 2 Nest preference does affect distribution of bees over the landscape, with cavity-nesting bees being restricted to nesting along field edges, which inevitably leads to performance reductions. Fragmentation mitigates this for cavity-nesting bees through increased edge habitat. 3 Landscape fragmentation alone had a relatively small effect on all responses. Instead, the local ratio of nest to foraging habitat affected bee fitness positively through reduced local competition. The spatial coverage of pollination increases steeply in response

  12. Níveis crescentes de feno em dietas à base de palma forrageira para caprinos em confinamento:comportamento ingestivo - DOI: 10.4025/actascianimsci.v27i4.1152 Increasing hay levels in forage cactus based diets for goats in feedlot: ingestive behavior - DOI: 10.4025/actascianimsci.v27i4.1152

    Directory of Open Access Journals (Sweden)

    Marcelo de Andrade Ferreira

    2005-03-01

    Full Text Available O experimento foi realizado de janeiro a abril de 2004, com o objetivo de avaliar o comportamento ingestivo de caprinos alimentados com rações contendo 5; 15; 25; 35; e 45% de feno de capim-tifton (Cynodon dactylon, (L Pers em dietas à base de palma forrageira (Opuntia ficus-indica, Mill. Foram utilizados 5 animais, fistulados no rúmen, distribuídos em quadrado latino 5x5. Os consumos de matéria seca, em kg/dia e em % do peso vivo (PV, e de fibra em detergente neutro, em % PV, apresentaram comportamento quadrático ( P 0,05 dos níveis de feno sobre as atividades de defecação, micção, procura pela água e posição preferencial em deitarThe experiment was carried out from January to April 2004. Five animals fed with ruminal cannula were randomly allocated in 5x5 square, to evaluate ingestive behavior and physiologic parameters. Animals were fed with forage cactus (Opuntia ficus-indica, Mill - based diets with 5; 15; 25; 35; and 45% tifton hay (Cynodon dactylon,(L. Pers. There was a quadratic relationship between dry matter (kg/day and % live weight (LW and neutral detergent fiber (% LW intake and tifton hay inclusion. Idleness time reduced whereas rumination, eating and chewing time increased linearly ( P 0.05 defecation, urination, water search and lying down position

  13. Increased Foraging in Outdoor Organic Pig Production—Modeling Environmental Consequences

    Directory of Open Access Journals (Sweden)

    Malene Jakobsen

    2015-11-01

    Full Text Available Consumers’ motivations for buying organic products include a wish of acquiring healthy, environmentally friendly products from production systems that also ensure a high level of animal welfare. However, the current Danish organic pig production faces important challenges regarding environmental impact of the system. High ammonia emissions arise from outdoor concrete areas with growing pigs and sows on pasture possess an increased risk of nitrogen (N leaching. Direct foraging in the range area is suggested as a way to improve the nutrient efficiency at farm level and to support a more natural behavior of the pig. Thus, by modeling, we investigated the environmental consequences of two alternative scenarios with growing pigs foraging in the range area and different levels of crops available for foraging—grass–clover or a combination of Jerusalem artichokes and lucerne. It was possible to have growing pigs on free-range without increasing N leaching compared to the current practice. The alternative system with Jerusalem artichokes and lucerne (high integration of forage showed the lowest carbon foot print with 3.12 CO2 eq kg−1 live weight pig compared to the current Danish pasture based system with 3.69 kg CO2 eq kg−1 live weight pig. Due to positive impact on soil carbon sequestration, the second alternative system based on grass-clover (low integration of forage showed a similar carbon foot print compared to current practice with 3.68 kg CO2 eq kg−1 live weight pig. It is concluded that in practice there is room for development of organic farming systems where direct foraging plays a central role.

  14. Methane emission from animals: A Global High-Resolution Data Base

    Science.gov (United States)

    Lerner, Jean; Matthews, Elaine; Fung, Inez

    1988-06-01

    We present a high-resolution global data base of animal population densities and associated methane emission. Statistics on animal populations from the Food and Agriculture Organization and other sources have been compiled. Animals were distributed using a 1° resolution data base of countries of the world and a 1° resolution data base of land use. The animals included are cattle and dairy cows, water buffalo, sheep, goats, camels, pigs, horses and caribou. Published estimates of methane production from each type of animal have been applied to the animal populations to yield a global distribution of annual methane emission by animals. There is large spatial variability in the distribution of animal populations and their methane emissions. Emission rates greater than 5000 kg CH4 km-2 yr-1 are found in small regions such as Bangladesh, the Benelux countries, parts of northern India, and New Zealand. Of the global annual emission of 75.8 Tg CH4 for 1984, about 55% is concentrated between 25°N and 55°N, a significant contribution to the observed north-south gradient of atmospheric methane concentration. A magnetic tape of the global data bases is available from the authors.

  15. Predicting animal production on sourveld: a species-based approach

    African Journals Online (AJOL)

    Presents a simulation model which was developed to predict average daily gain in cattle and sheep grazing different species and swards of different species composition on Dohne Sourveld. The model was based upon measured ingestive and digestive characteristics of different grass species and incorporates an explicit ...

  16. Tool use by aquatic animals

    Science.gov (United States)

    Mann, Janet; Patterson, Eric M.

    2013-01-01

    Tool-use research has focused primarily on land-based animals, with less consideration given to aquatic animals and the environmental challenges and conditions they face. Here, we review aquatic tool use and examine the contributing ecological, physiological, cognitive and social factors. Tool use among aquatic animals is rare but taxonomically diverse, occurring in fish, cephalopods, mammals, crabs, urchins and possibly gastropods. While additional research is required, the scarcity of tool use can likely be attributable to the characteristics of aquatic habitats, which are generally not conducive to tool use. Nonetheless, studying tool use by aquatic animals provides insights into the conditions that promote and inhibit tool-use behaviour across biomes. Like land-based tool users, aquatic animals tend to find tools on the substrate and use tools during foraging. However, unlike on land, tool users in water often use other animals (and their products) and water itself as a tool. Among sea otters and dolphins, the two aquatic tool users studied in greatest detail, some individuals specialize in tool use, which is vertically socially transmitted possibly because of their long dependency periods. In all, the contrasts between aquatic- and land-based tool users enlighten our understanding of the adaptive value of tool-use behaviour. PMID:24101631

  17. Departure time influences foraging associations in little penguins.

    Science.gov (United States)

    Sutton, Grace J; Hoskins, Andrew J; Berlincourt, Maud; Arnould, John P Y

    2017-01-01

    Recent studies have documented that little penguins (Eudyptula minor) associate at sea, displaying synchronised diving behaviour throughout a foraging trip. However, previous observations were limited to a single foraging trip where only a small number of individuals were simultaneously tracked. Consequently, it is not known whether coordinated behaviour is consistent over time, or what factors influence it. In the present study, breeding adults were concurrently instrumented with GPS and dive behaviour data loggers for at least 2 consecutive foraging trips during guard and post-guard stage at two breeding colonies (London Bridge and Gabo Island, south-eastern Australia) of contrasting population size (approximately 100 and 30,000-40,000, respectively). At both colonies, individuals were sampled in areas of comparable nesting density and spatial area. At London Bridge, where individuals use a short (23 m) common pathway from their nests to the shoreline, > 90% (n = 42) of birds displayed foraging associations and 53-60% (n = 20) maintained temporally consistent associations with the same conspecifics. Neither intrinsic (sex, size or body condition) nor extrinsic (nest proximity) factors were found to influence foraging associations. However, individuals that departed from the colony at a similar time were more likely to associate during a foraging trip. At Gabo Island, where individuals use a longer (116 m) pathway with numerous tributaries to reach the shoreline, few individuals (< 31%; n = 13) from neighbouring nests associated at sea and only 1% (n = 1) maintained associations over subsequent trips. However, data from animal-borne video cameras indicated individuals at this colony displayed foraging associations of similar group size to those at London Bridge. This study reveals that group foraging behaviour occurs at multiple colonies and the pathways these individuals traverse with conspecifics may facilitate opportunistic group formation and resulting in

  18. Departure time influences foraging associations in little penguins.

    Directory of Open Access Journals (Sweden)

    Grace J Sutton

    Full Text Available Recent studies have documented that little penguins (Eudyptula minor associate at sea, displaying synchronised diving behaviour throughout a foraging trip. However, previous observations were limited to a single foraging trip where only a small number of individuals were simultaneously tracked. Consequently, it is not known whether coordinated behaviour is consistent over time, or what factors influence it. In the present study, breeding adults were concurrently instrumented with GPS and dive behaviour data loggers for at least 2 consecutive foraging trips during guard and post-guard stage at two breeding colonies (London Bridge and Gabo Island, south-eastern Australia of contrasting population size (approximately 100 and 30,000-40,000, respectively. At both colonies, individuals were sampled in areas of comparable nesting density and spatial area. At London Bridge, where individuals use a short (23 m common pathway from their nests to the shoreline, > 90% (n = 42 of birds displayed foraging associations and 53-60% (n = 20 maintained temporally consistent associations with the same conspecifics. Neither intrinsic (sex, size or body condition nor extrinsic (nest proximity factors were found to influence foraging associations. However, individuals that departed from the colony at a similar time were more likely to associate during a foraging trip. At Gabo Island, where individuals use a longer (116 m pathway with numerous tributaries to reach the shoreline, few individuals (< 31%; n = 13 from neighbouring nests associated at sea and only 1% (n = 1 maintained associations over subsequent trips. However, data from animal-borne video cameras indicated individuals at this colony displayed foraging associations of similar group size to those at London Bridge. This study reveals that group foraging behaviour occurs at multiple colonies and the pathways these individuals traverse with conspecifics may facilitate opportunistic group formation and

  19. Comparative Sucrose Responsiveness in Apis mellifera and A. cerana Foragers

    Science.gov (United States)

    Yang, Wenchao; Kuang, Haiou; Wang, Shanshan; Wang, Jie; Liu, Wei; Wu, Zhenhong; Tian, Yuanyuan; Huang, Zachary Y.; Miao, Xiaoqing

    2013-01-01

    In the European honey bee, Apis mellifera, pollen foragers have a higher sucrose responsiveness than nectar foragers when tested using a proboscis extension response (PER) assay. In addition, Africanized honey bees have a higher sucrose responsiveness than European honey bees. Based on the biology of the Eastern honey bee, A. cerana, we hypothesized that A. cerana should also have a higher responsiveness to sucrose than A. mellifera. To test this hypothesis, we compared the sucrose thresholds of pollen foragers and nectar foragers in both A. cerana and A. mellifera in Fujian Province, China. Pollen foragers were more responsive to sucrose than nectar foragers in both species, consistent with previous studies. However, contrary to our hypothesis, A. mellifera was more responsive than A. cerana. We also demonstrated that this higher sucrose responsiveness in A. mellifera was not due to differences in the colony environment by co-fostering two species of bees in the same mixed-species colonies. Because A. mellifera foragers were more responsive to sucrose, we predicted that their nectar foragers should bring in less concentrated nectar compared to that of A. cerana. However, we found no differences between the two species. We conclude that A. cerana shows a different pattern in sucrose responsiveness from that of Africanized bees. There may be other mechanisms that enable A. cerana to perform well in areas with sparse nectar resources. PMID:24194958

  20. Effect of forage quality in faeces from different ruminant species fed high and low quality forage

    DEFF Research Database (Denmark)

    Jalali, A R; Nørgaard, P; Nielsen, M O

    2010-01-01

    Effect of forage quality in faeces from different ruminant species fed high and low quality forage......Effect of forage quality in faeces from different ruminant species fed high and low quality forage...

  1. Group cohesion in foraging meerkats: follow the moving 'vocal hot spot'.

    Science.gov (United States)

    Gall, Gabriella E C; Manser, Marta B

    2017-04-01

    Group coordination, when 'on the move' or when visibility is low, is a challenge faced by many social living animals. While some animals manage to maintain cohesion solely through visual contact, the mechanism of group cohesion through other modes of communication, a necessity when visual contact is reduced, is not yet understood. Meerkats ( Suricata suricatta ), a small, social carnivore, forage as a cohesive group while moving continuously. While foraging, they frequently emit 'close calls', soft close-range contact calls. Variations in their call rates based on their local environment, coupled with individual movement, produce a dynamic acoustic landscape with a moving 'vocal hotspot' of the highest calling activity. We investigated whether meerkats follow such a vocal hotspot by playing back close calls of multiple individuals to foraging meerkats from the front and back edge of the group simultaneously. These two artificially induced vocal hotspots caused the group to spatially elongate and split into two subgroups. We conclude that meerkats use the emergent dynamic call pattern of the group to adjust their movement direction and maintain cohesion. Our study describes a highly flexible mechanism for the maintenance of group cohesion through vocal communication, for mobile species in habitats with low visibility and where movement decisions need to be adjusted continuously to changing environmental conditions.

  2. Ab initio chemical safety assessment: A workflow based on exposure considerations and non-animal methods

    OpenAIRE

    Berggren, Elisabet; White, Andrew; Ouedraogo, Gladys; Paini, Alicia; Richarz, Andrea-Nicole; Bois, Frederic Y.; Exner, Thomas; Leite, Sofia; Grunsven, Leo A. van; Worth, Andrew; Mahony, Catherine

    2017-01-01

    Highlights • A workflow for an exposure driven chemical safety assessment to avoid animal testing. • Hypothesis based on existing data, in silico modelling and biokinetic considerations. • A tool to inform targeted and toxicologically relevant in vitro testing.

  3. Effect of species and harvest maturity on the fatty acids profile of tropical forages

    NARCIS (Netherlands)

    Khan, N.A.; Farooq, M.W.; Ali, M.; Suleman, M.; Ahmad, N.; Sulaiman, S.M.; Cone, J.W.; Hendriks, W.H.

    2015-01-01

    The aim of this study was to quantify the fatty acid (FA) content and composition of forages commonly fed to dairy animals in the tropics. Twelve forage species, namely, Trifolium alexandrinum, Cichorium intybus, Hordeum vulgare L., Medicago sativa, Avena sativa, Pennisetum purpureum Setaria anceps,

  4. Understanding the Foraging Ecology of Beaked and Short-Finned Pilot Whales in Hawaiian Waters

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Understanding the Foraging Ecology of Beaked and Short...critical in understanding the foraging behavior and life cycle of beaked whales. The movement patterns of any animals are strongly affected by the

  5. Foraging and public information use in common pipistrelle bats (Pipistrellus pipistrellus): a field experiment

    NARCIS (Netherlands)

    Jonker, M.N.; Boer, de W.F.; Kurvers, R.H.J.M.; Dekker, J.J.A.

    2010-01-01

    Decision making by animals is likely to be influenced strongly by the behaviour of conspecifics. In this study we tested whether public information affected the foraging behaviour of common pipistrelles (Pipistrellus pipistrellus) by manipulating public information about the quality of foraging

  6. Do inter-colony differences in Cape fur seal foraging behaviour ...

    African Journals Online (AJOL)

    We investigated how such environmental variability may impact foraging behaviour of the Cape fur seal Arctocephalus pusillus pusillus, using satellite telemetry on animals in northern, central and southern Namibia. We expected that seal foraging behaviour would reflect a gradient of deteriorating feeding conditions from ...

  7. Foraging innovation is inversely related to competitive ability in male but not in female guppies

    NARCIS (Netherlands)

    Laland, K.N.; Reader, S.M.

    1999-01-01

    Foraging success is likely to affect hunger level and motivation to locate and exploit novel food sources in animals. We explored the relationship between scramble competition for limited food and foraging innovation in the guppy (Poecilia reticulata), predicting that poor competitors would be more

  8. Learning foraging thresholds for lizards

    Energy Technology Data Exchange (ETDEWEB)

    Goldberg, L.A. [Univ. of Warwick, Coventry (United Kingdom). Dept. of Computer Science; Hart, W.E. [Sandia National Labs., Albuquerque, NM (United States); Wilson, D.B. [Massachusetts Inst. of Tech., Cambridge, MA (United States)

    1996-01-12

    This work gives a proof of convergence for a randomized learning algorithm that describes how anoles (lizards found in the Carribean) learn a foraging threshold distance. This model assumes that an anole will pursue a prey if and only if it is within this threshold of the anole`s perch. This learning algorithm was proposed by the biologist Roughgarden and his colleagues. They experimentally confirmed that this algorithm quickly converges to the foraging threshold that is predicted by optimal foraging theory our analysis provides an analytic confirmation that the learning algorithm converses to this optimal foraging threshold with high probability.

  9. Produção de forragem em pastagens consorciadas com diferentes leguminosas sob pastejo rotacionado = Forage production in pasture-based systems mixed with different legumes under rotational grazing

    Directory of Open Access Journals (Sweden)

    Edilene Steinwandter

    2009-04-01

    Full Text Available O objetivo desta pesquisa foi avaliar dois sistemas forrageiros, constituídos por capim-elefante, azevém, trevo branco ou amendoim forrageiro e espécies de crescimento espontâneo, quanto às taxas de acúmulo e de desaparecimento de MS. Para avaliação utilizaram-se quatro piquetes, com 0,25 ha cada um, com capim-elefante estabelecido em linhas afastadas a cada 4 m. No período hibernal, entre as linhas do capim-elefante, fez-se o estabelecimento do azevém; em dois piquetes foi semeado o trevo branco e nos demais se preservou o amendoim forrageiro. O delineamento experimental utilizado foi inteiramente casualizado. Para a determinação das taxas de acúmulo e de desaparecimento de MS, avaliaram-se as massas de forragem de pré e pós-pastejo. Foram avaliadas a composição botânica e estrutural da pastagem e a lotação. Na média, as taxas de acúmulo e dedesaparecimento da MS e a lotação foram de 47,29 kg de MS ha-1 dia-1; 3,24% e 3,01 UA ha-1 e de 53,16 kg de MS ha-1 dia-1; 3,45% e 3,48 UA ha-1 para os sistemas constituídos por trevo branco e por amendoim forrageiro, respectivamente. Considerando-se a taxa de acúmulo deMS, a MS desaparecida e a lotação, os resultados demonstram melhores resultados para o sistema forrageiro constituído pelo amendoim forrageiro.The objective of this research was to evaluate two pasture-based systems, with elephantgrass, ryegrass, white clover or forage peanut and spontaneous growth species about the accumulation rate and of disappearance of forage mass. The elephantgrass was established in rows with a distance of 4 m between rows. In the cool season, ryegrass was planted between rows of elephantgrass; white clover wassowed,in two paddocks, and in the other two the forage peanut was preserved. The experimental design was completely randomized. In order to stipulate the accumulation rate and of disappearance of forage mass, the pre- and post-graze forage mass were evaluated.The botanical and

  10. Integrating Model-Based Learning and Animations for Enhancing Students' Understanding of Proteins Structure and Function

    Science.gov (United States)

    Barak, Miri; Hussein-Farraj, Rania

    2013-04-01

    This paper describes a study conducted in the context of chemistry education reforms in Israel. The study examined a new biochemistry learning unit that was developed to promote in-depth understanding of 3D structures and functions of proteins and nucleic acids. Our goal was to examine whether, and to what extent teaching and learning via model-based learning and animations of biomolecules affect students' chemical understanding. Applying the mixed methods research paradigm, pre- and post-questionnaires as well as class-observations were employed in the collection, analysis, and interpretation of data. The research population included 175 grade twelve students, divided into three research groups: (a) hands-on exploration of animations, (b) teacher's demonstrations of animations, (c) traditional learning using textbooks. Findings indicated that the integration of model-based learning and 3D animations enhanced students' understanding of proteins' structure and function and their ability to transfer across different levels of chemistry understanding. Findings also indicated that teachers' demonstrations of animations may enhance students' `knowledge'—a low order thinking skill; however, in order to enhance higher levels of thinking, students should be able to explore 3D animations on their own. Applying constructivist and interpretative analysis of the data, three themes were raised, corresponding to cognitive, affective, and social aspects of learning while exploring web-based models and animations.

  11. Forage and breed effects on behavior and temperament of pregnant beef heifers.

    Science.gov (United States)

    Mays, Angela R; Looper, Michael L; Williamson, Benjamin C; Coffey, Kenneth P; Coblentz, Wayne K; Aiken, Glen E; Rosenkrans, Charles F

    2013-01-01

    Integration of behavioral observations with traditional selection schemes may lead to enhanced animal well-being and more profitable forage-based cattle production systems. Brahman-influenced (BR; n = 64) and Gelbvieh × Angus (GA; n = 64) heifers consumed either toxic endophyte-infected tall fescue (E+) or one of two nontoxic endophyte-infected tall fescue (NT) cultivars during two yr. Heifers were weighed at midpoint and termination of grazing. Grazing behavior (grazing, resting in the shade, lying, or standing without grazing) was recorded (n = 13 visual observations per yr in June and July) for each pasture. During yr 2, exit velocity (EV) and serum prolactin (PRL) were determined. Grazing behavior was influenced (P heifers assigned to E+ pastures had the lowest percentage of animals grazing and the largest percentage of animals resting in the shade. Brahman-influenced heifers had faster EV (P heifers (0.52 vs. 0.74 ± 0.04 s/m, respectively). Body weight (BW) was affected (P Heifers grazing NT pastures were heavier (P heifers grazing E+ pastures at midpoint and termination. Gelbvieh × Angus heifers grazing NT pastures were heavier (P heifers grazing E+ and BR heifers grazing NT pastures. An interaction of forage cultivar and breed type occurred on serum PRL (P Heifers grazing NT pastures were observed to be grazing more than heifers assigned to E+ pastures, regardless of breed type, which may have contributed to changes in BW and average daily gain (ADG) in heifers. Integration of behavioral observations along with traditional selection schemes may lead to enhanced animal well-being and more profitable forage-based cattle production systems.

  12. Effects of treated waste water irrigation on some qualitative charcterstics of forage sorghum, corn and millet

    Directory of Open Access Journals (Sweden)

    alireza emami

    2009-06-01

    Full Text Available In order to study the effects of irrigation with different levels of urban treated waste water on feeding value of forage sorghum (Var. Speed feed and Sugar graze, maize (Var. SC 704 and millet (Var. Nutrifeed an experiment was conducted at Experimental Station No.1, Astan Qods Razavi Mashhad, and Animal Nutrition Laboratory, College of Agriculture, Ferdowsi University of Mashhad. Four varieties of forage plants with five levels of treated waste water: %0, %25, %50, %75 and %100 were compared in a split-plot experiment based on Randomized Complete Block Design with four replications per treatment. Feeding values of forage plants such as Crude Protein content (CP, Neutral Detergent Fiber content (NDF, in vitro Dry Matter Digestibility (DMD, Organic Matter Digestibility (OMD and D-Value were measured. Results showed that treated waste water irrigation had a significant effect on crude protein content. The highest crude protein content was shown at % 100 treated waste water ( %13.76 and the lowest was shown at % treated waste water (%9.54. There were no significant differences between %0 and %25, and also %75 and %100 treated waste water in terms of crude protein content, but there were significant differences between %50 and other treated waste water treatments (except 75% treatments. There were no significant difference between irrigation with different levels of treated waste water in terms of NDF, in vitro DMD, OMD, and D-Value. There were significant differences between forage plants in all studied characteristics, but there were no significant differences on interactions between forage plants and different levels of treated waste water treatments. Forage maize had the highest in vitro DMD at %75 treated waste water and forage sorghum (var. Speed feed had the lowest in vitro DMD at %0 treated waste water treatments with averages of %77.57 and %61.6, respectively. The results indicated that treated waste water increased the percentage of crude

  13. Survey of Canadian Animal-Based Researchers' Views on the Three Rs: Replacement, Reduction and Refinement

    Science.gov (United States)

    Fenwick, Nicole; Danielson, Peter; Griffin, Gilly

    2011-01-01

    The ‘Three Rs’ tenet (replacement, reduction, refinement) is a widely accepted cornerstone of Canadian and international policies on animal-based science. The Canadian Council on Animal Care (CCAC) initiated this web-based survey to obtain greater understanding of ‘principal investigators’ and ‘other researchers’ (i.e. graduate students, post-doctoral researchers etc.) views on the Three Rs, and to identify obstacles and opportunities for continued implementation of the Three Rs in Canada. Responses from 414 participants indicate that researchers currently do not view the goal of replacement as achievable. Researchers prefer to use enough animals to ensure quality data is obtained rather than using the minimum and potentially waste those animals if a problem occurs during the study. Many feel that they already reduce animal numbers as much as possible and have concerns that further reduction may compromise research. Most participants were ambivalent about re-use, but expressed concern that the practice could compromise experimental outcomes. In considering refinement, many researchers feel there are situations where animals should not receive pain relieving drugs because it may compromise scientific outcomes, although there was strong support for the Three Rs strategy of conducting animal welfare-related pilot studies, which were viewed as useful for both animal welfare and experimental design. Participants were not opposed to being offered “assistance” to implement the Three Rs, so long as the input is provided in a collegial manner, and from individuals who are perceived as experts. It may be useful for animal use policymakers to consider what steps are needed to make replacement a more feasible goal. In addition, initiatives that offer researchers greater practical and logistical support with Three Rs implementation may be useful. Encouragement and financial support for Three Rs initiatives may result in valuable contributions to Three Rs

  14. Survey of Canadian animal-based researchers' views on the Three Rs: replacement, reduction and refinement.

    Directory of Open Access Journals (Sweden)

    Nicole Fenwick

    Full Text Available The 'Three Rs' tenet (replacement, reduction, refinement is a widely accepted cornerstone of Canadian and international policies on animal-based science. The Canadian Council on Animal Care (CCAC initiated this web-based survey to obtain greater understanding of 'principal investigators' and 'other researchers' (i.e. graduate students, post-doctoral researchers etc. views on the Three Rs, and to identify obstacles and opportunities for continued implementation of the Three Rs in Canada. Responses from 414 participants indicate that researchers currently do not view the goal of replacement as achievable. Researchers prefer to use enough animals to ensure quality data is obtained rather than using the minimum and potentially waste those animals if a problem occurs during the study. Many feel that they already reduce animal numbers as much as possible and have concerns that further reduction may compromise research. Most participants were ambivalent about re-use, but expressed concern that the practice could compromise experimental outcomes. In considering refinement, many researchers feel there are situations where animals should not receive pain relieving drugs because it may compromise scientific outcomes, although there was strong support for the Three Rs strategy of conducting animal welfare-related pilot studies, which were viewed as useful for both animal welfare and experimental design. Participants were not opposed to being offered "assistance" to implement the Three Rs, so long as the input is provided in a collegial manner, and from individuals who are perceived as experts. It may be useful for animal use policymakers to consider what steps are needed to make replacement a more feasible goal. In addition, initiatives that offer researchers greater practical and logistical support with Three Rs implementation may be useful. Encouragement and financial support for Three Rs initiatives may result in valuable contributions to Three Rs

  15. Survey of Canadian animal-based researchers' views on the Three Rs: replacement, reduction and refinement.

    Science.gov (United States)

    Fenwick, Nicole; Danielson, Peter; Griffin, Gilly

    2011-01-01

    The 'Three Rs' tenet (replacement, reduction, refinement) is a widely accepted cornerstone of Canadian and international policies on animal-based science. The Canadian Council on Animal Care (CCAC) initiated this web-based survey to obtain greater understanding of 'principal investigators' and 'other researchers' (i.e. graduate students, post-doctoral researchers etc.) views on the Three Rs, and to identify obstacles and opportunities for continued implementation of the Three Rs in Canada. Responses from 414 participants indicate that researchers currently do not view the goal of replacement as achievable. Researchers prefer to use enough animals to ensure quality data is obtained rather than using the minimum and potentially waste those animals if a problem occurs during the study. Many feel that they already reduce animal numbers as much as possible and have concerns that further reduction may compromise research. Most participants were ambivalent about re-use, but expressed concern that the practice could compromise experimental outcomes. In considering refinement, many researchers feel there are situations where animals should not receive pain relieving drugs because it may compromise scientific outcomes, although there was strong support for the Three Rs strategy of conducting animal welfare-related pilot studies, which were viewed as useful for both animal welfare and experimental design. Participants were not opposed to being offered "assistance" to implement the Three Rs, so long as the input is provided in a collegial manner, and from individuals who are perceived as experts. It may be useful for animal use policymakers to consider what steps are needed to make replacement a more feasible goal. In addition, initiatives that offer researchers greater practical and logistical support with Three Rs implementation may be useful. Encouragement and financial support for Three Rs initiatives may result in valuable contributions to Three Rs knowledge and improve

  16. Animals as sentinels of chemical terrorism agents: an evidence-based review.

    Science.gov (United States)

    Rabinowitz, Peter; Wiley, James; Odofin, Lynda; Wilcox, Matthew; Dein, F Joshua

    2008-02-01

    The goal of this systematic review was to identify evidence that animals could serve as sentinels of an attack with a chemical terrorism agent. The biomedical literature was systematically searched for evidence that wild or domestic animals exposed to certain chemical weapons of terrorism had either greater susceptibility, shorter latency period, or increased exposure risk versus humans. Additionally, we searched for documented reports of such animals historically serving as sentinels for chemical warfare agents. For a small number of agents, there was limited evidence that domestic and/or wild animals could provide sentinel information to humans following an airborne attack with chemical agents, usually related to increased potential for environmental exposure. Some of this evidence was based on anecdotal case reports, and in many cases high quality chemical terrorism agent evidence regarding comparative susceptibility, exposure, and latency between humans and sentinel animal species was not found. Currently, there is insufficient evidence for routine use of animals as sentinels for airborne chemical warfare agents. At the same time, Poison Center surveillance systems should include animal calls, and greater communication between veterinarians and physicians could help with preparedness for a chemical terrorism attack. Further analysis of comparative chemical warfare agent toxicity between sentinel animal species and humans is needed.

  17. Virtual Character Animation Based on Affordable Motion Capture and Reconfigurable Tangible Interfaces.

    Science.gov (United States)

    Lamberti, Fabrizio; Paravati, Gianluca; Gatteschi, Valentina; Cannavo, Alberto; Montuschi, Paolo

    2018-05-01

    Software for computer animation is generally characterized by a steep learning curve, due to the entanglement of both sophisticated techniques and interaction methods required to control 3D geometries. This paper proposes a tool designed to support computer animation production processes by leveraging the affordances offered by articulated tangible user interfaces and motion capture retargeting solutions. To this aim, orientations of an instrumented prop are recorded together with animator's motion in the 3D space and used to quickly pose characters in the virtual environment. High-level functionalities of the animation software are made accessible via a speech interface, thus letting the user control the animation pipeline via voice commands while focusing on his or her hands and body motion. The proposed solution exploits both off-the-shelf hardware components (like the Lego Mindstorms EV3 bricks and the Microsoft Kinect, used for building the tangible device and tracking animator's skeleton) and free open-source software (like the Blender animation tool), thus representing an interesting solution also for beginners approaching the world of digital animation for the first time. Experimental results in different usage scenarios show the benefits offered by the designed interaction strategy with respect to a mouse & keyboard-based interface both for expert and non-expert users.

  18. Foraging traits modulate stingless bee community disassembly under forest loss.

    Science.gov (United States)

    Lichtenberg, Elinor M; Mendenhall, Chase D; Brosi, Berry

    2017-10-01

    Anthropogenic land use change is an important driver of impacts to biological communities and the ecosystem services they provide. Pollination is one ecosystem service that may be threatened by community disassembly. Relatively little is known about changes in bee community composition in the tropics, where pollination limitation is most severe and land use change is rapid. Understanding how anthropogenic changes alter community composition and functioning has been hampered by high variability in responses of individual species. Trait-based approaches, however, are emerging as a potential method for understanding responses of ecologically similar species to global change. We studied how communities of tropical, eusocial stingless bees (Apidae: Meliponini) disassemble when forest is lost. These bees are vital tropical pollinators that exhibit high trait diversity, but are under considerable threat from human activities. We compared functional traits of stingless bee species found in pastures surrounded by differing amounts of forest in an extensively deforested landscape in southern Costa Rica. Our results suggest that foraging traits modulate competitive interactions that underlie community disassembly patterns. In contrast to both theoretical predictions and temperate bee communities, we found that stingless bee species with the widest diet breadths were less likely to persist in sites with less forest. These wide-diet-breadth species also tend to be solitary foragers, and are competitively subordinate to group-foraging stingless bee species. Thus, displacement by dominant, group-foraging species may make subordinate species more dependent on the larger or more diversified resource pool that natural habitats offer. We also found that traits that may reduce reliance on trees-nesting in the ground or inside nests of other species-correlated with persistence in highly deforested landscapes. The functional trait perspective we employed enabled capturing community

  19. Functional visual sensitivity to ultraviolet wavelengths in the Pileated Woodpecker (Dryocopus pileatus), and its influence on foraging substrate selection

    Science.gov (United States)

    O'Daniels, Sean T.; Kesler, Dylan C.; Mihail, Jeanne D.; Webb, Elisabeth B.; Werner, Scott J.

    2017-01-01

    Most diurnal birds are presumed visually sensitive to near ultraviolet (UV) wavelengths, however, controlled behavioral studies investigating UV sensitivity remain few. Although woodpeckers are important as primary cavity excavators and nuisance animals, published work on their visual systems is limited. We developed a novel foraging-based behavioral assay designed to test UV sensitivity in the Pileated Woodpecker (Dryocopus pileatus). We acclimated 21 wild-caught woodpeckers to foraging for frozen mealworms within 1.2 m sections of peeled cedar (Thuja spp.) poles. We then tested the functional significance of UV cues by placing frozen mealworms behind UV-reflective covers, UV-absorptive covers, or decayed red pine substrates within the same 1.2 m poles in independent experiments. Behavioral responses were greater toward both UV-reflective and UV-absorptive substrates in three experiments. Study subjects therefore reliably differentiated and attended to two distinct UV conditions of a foraging substrate. Cue-naïve subjects showed a preference for UV-absorptive substrates, suggesting that woodpeckers may be pre-disposed to foraging from such substrates. Behavioral responses were greater toward decayed pine substrates (UV-reflective) than sound pine substrates suggesting that decayed pine can be a useful foraging cue. The finding that cue-naïve subjects selected UV-absorbing foraging substrates has implications for ecological interactions of woodpeckers with fungi. Woodpeckers transport fungal spores, and communication methods analogous to those of plant-pollinator mutualisms (i.e. UV-absorbing patterns) may have evolved to support woodpecker-fungus mutualisms.

  20. Foraging behavior analysis of swarm robotics system

    Directory of Open Access Journals (Sweden)

    Sakthivelmurugan E.

    2018-01-01

    Full Text Available Swarm robotics is a number of small robots that are synchronically works together to accomplish a given task. Swarm robotics faces many problems in performing a given task. The problems are pattern formation, aggregation, Chain formation, self-assembly, coordinated movement, hole avoidance, foraging and self-deployment. Foraging is most essential part in swarm robotics. Foraging is the task to discover the item and get back into the shell. The researchers conducted foraging experiments with random-movement of robots and they have end up with unique solutions. Most of the researchers have conducted experiments using the circular arena. The shell is placed at the centre of the arena and environment boundary is well known. In this study, an attempt is made to different strategic movements like straight line approach, parallel line approach, divider approach, expanding square approach, and parallel sweep approach. All these approaches are to be simulated by using player/stage open-source simulation software based on C and C++ programming language in Linux operating system. Finally statistical comparison will be done with task completion time of all these strategies using ANOVA to identify the significant searching strategy.

  1. Development of a SiPM-based PET imaging system for small animals

    International Nuclear Information System (INIS)

    Lu, Yanye; Yang, Kun; Zhou, Kedi; Zhang, Qiushi; Pang, Bo; Ren, Qiushi

    2014-01-01

    Advances in small animal positron emission tomography (PET) imaging have been accelerated by many new technologies such as the successful incorporation of silicon photomultiplier (SiPM). In this paper, we have developed a compact, lightweight PET imaging system that is based on SiPM detectors for small animals imaging, which could be integrated into a multi-modality imaging system. This PET imaging system consists of a stationary detector gantry, a motor-controlled animal bed module, electronics modules, and power supply modules. The PET detector, which was designed as a multi-slice circular ring geometry of 27 discrete block detectors, is composed of a cerium doped lutetium–yttrium oxyorthosilicate (LYSO) scintillation crystal and SiPM arrays. The system has a 60 mm transaxial field of view (FOV) and a 26 mm axial FOV. Performance tests (e.g. spatial resolution, energy resolution, and sensitivity) and phantom and animal imaging studies were performed to evaluate the imaging performance of the PET imaging system. The performance tests and animal imaging results demonstrate the feasibility of an animal PET system based on SiPM detectors and indicate that SiPM detectors can be promising photodetectors in animal PET instrumentation development

  2. ORBITAL TRAJECTORY SIMULATION ON TWIN STARS SYSTEM IN IFS FRACTAL MODEL BASED ON HYBRID ANIMATION METHOD

    Directory of Open Access Journals (Sweden)

    Tedjo Darmanto

    2015-08-01

    Full Text Available IFS (Iterated Function Systems is a method to model fractal object based on affine transformation functions. The star-like object rotation effect in the IFS fractal model could be exhibited by using metamorphical method, as a replacement to the affine rotation method on a non metamorphic animation. The advantage of a metamorphic animation method over the metamorphic animation method is that the object's relative position to the fixed point as an absolute centroid is absolute. Therefore, the rotational effect can be exhibited at any positions. In addition, it can also be combined with rotational effect of the local centroid itself around the absolute centroid as a fixed point by the primitive rotational operation to form an interesting behavior of orbital trajectory Based on the hybrid of both animation methods, the animation simulation could be done on orbital trajectory on a twin stars rotating to each other as a system. Both objects are rotated in the same angular direction, but started in the opposite position around two closely different fixed points. So, the orbital trajectory yielded forms an elliptical path. The two similar objects can be created efficiently by cloning-scaling technique. In general, the animation method can be modeled as an animation framework.

  3. Impact of audio narrated animation on students' understanding and learning environment based on gender

    Science.gov (United States)

    Nasrudin, Ajeng Ratih; Setiawan, Wawan; Sanjaya, Yayan

    2017-05-01

    This study is titled the impact of audio narrated animation on students' understanding in learning humanrespiratory system based on gender. This study was conducted in eight grade of junior high school. This study aims to investigate the difference of students' understanding and learning environment at boys and girls classes in learning human respiratory system using audio narrated animation. Research method that is used is quasy experiment with matching pre-test post-test comparison group design. The procedures of study are: (1) preliminary study and learning habituation using audio narrated animation; (2) implementation of learning using audio narrated animation and taking data; (3) analysis and discussion. The result of analysis shows that there is significant difference on students' understanding and learning environment at boys and girls classes in learning human respiratory system using audio narrated animation, both in general and specifically in achieving learning indicators. The discussion related to the impact of audio narrated animation, gender characteristics, and constructivist learning environment. It can be concluded that there is significant difference of students' understanding at boys and girls classes in learning human respiratory system using audio narrated animation. Additionally, based on interpretation of students' respond, there is the difference increment of agreement level in learning environment.

  4. Plant-beneficial elements status assessment in soil-plant system in the vicinity of a chemical industry complex: shedding light on forage grass safety issues.

    Science.gov (United States)

    Anjum, Naser A; Duarte, Armando C; Pereira, Eduarda; Ahmad, Iqbal

    2015-02-01

    Human health is closely linked with soils via plants, grazers, or plant-based products. This study estimated plant-beneficial elements (macronutrients: K, P; secondary macronutrients: Ca, Mg; micronutrients: Mo, Mn, Na, Ni, Se) in both soils and shoots of two forage grass species (Eriophorum angustifolium and Lolium perenne) prevalent in the vicinity of a chemical industry complex (Estarreja, Portugal). Both soils and plants from the chemical industrial areas exhibited differential concentrations of the studied elements. In soils, the role of contamination was evidenced as insignificant in context of its impact on all the tested macro and secondary macronutrients except P, and micronutrients such as Mo and Ni. In forage grass plant shoots, the role of contamination was evidenced as insignificant in relation to its impact on all the tested macro and secondary macronutrients except K. Between the two forage grass plants, high Se-harboring L. perenne cannot be recommended for its use as animal feed.

  5. Animal house stock control based on bar-coded cage labels.

    Science.gov (United States)

    Wootton, R

    1985-10-01

    In an animal house serving the needs of a large research institute, a regular inventory of the animals in stock is a considerable help towards effective management of the facility. In particular, advising the licence-holders of what animals are being held in their name and reminding them of the costs involved is a valuable exercise. The introduction of a computerized system of stock control, based on bar-coded cage labels, is described. The system has proved economical to operate, accurate, and can be run by persons without computer expertise.

  6. Desempenho leiteiro de vacas alimentadas com caroço de algodão em dieta à base de palma forrageira Dairy cows performance fed whole cottonseed in a forage of cactus-base diet

    Directory of Open Access Journals (Sweden)

    Airon Aparecido Silva de Melo

    2006-07-01

    Full Text Available Este trabalho teve como objetivo avaliar o efeito da inclusão do caroço de algodão em dietas à base de palma forrageira (Opuntia ficus indica Mill., sobre o desempenho de vacas da raça Holandesa em lactação. O experimento foi feito com cinco vacas, com média de 50 dias de lactação, distribuídas em quadrado latino 5x5. Os tratamentos experimentais foram constituídos da inclusão de caroço de algodão em 0, 6,25, 12,50, 18,75 e 25% da matéria seca da dieta. O caroço de algodão aumentou o consumo de matéria seca, extrato etéreo, nutrientes digestíveis totais, cálcio e fósforo; porém não afetou o consumo de proteína bruta e fibra em detergente neutro. O caroço de algodão aumentou a produção de leite corrigido para 3,5% de gordura (de 26,53 para 31,68 kg por dia, e a produção de gordura do leite (de 0,86 para 1,09 kg por dia; não afetou, porém, a produção de leite sem correção (31,19 kg por dia, a porcentagem de gordura do leite (3,18% e a eficiência alimentar (1,31 kg de leite corrigido por quilograma de matéria seca consumida. O caroço de algodão melhorou o desempenho animal, quando incluído em até 25% da matéria seca em dietas à base de palma forrageira.The effect of the whole cottonseed on dairy cows performance fed forage cactus (Opuntia ficus indica Mill. diet was evaluated. Experiment was made with five Holstein cows, in a 50-days lactation, which were placed into a 5x5 latin square design. The whole cottonseed was added as a partial replacement of sorghum silage and soybean meal, in a level of 0, 6.25, 12.50, 18.75, and 25.00% of dry matter. It was observed that addition of whole cottonseed increased the dry matter, ether extract, total digestible nutrients, calcium and phosphorus intake, but did not affect the crude protein and neutral detergent fiber intake. Also, it increased the fat corrected milk yield 3.5% (26.53 to 31.68 kg per day and the fat milk yield (0.86 to 1.09 kg per day, but did not

  7. Forage evaluation by analysis after

    African Journals Online (AJOL)

    by forages, can be estimated by amino acid analysis of the products of fermentation in vitro. Typical results of such analyses are presented in Table 1. These results indicate that after fermentation the amino acid balance of forages is not optimal for either milk or meat production, with histidine usually being the first limiting.

  8. Forage kochia: Friend or foe

    Science.gov (United States)

    Blair L. Waldron; R. Deane Harrison; N. Jerry Chatterton; Burke W. Davenport

    2001-01-01

    Perennial forage kochia (Kochia prostrata) is a halfshrub valuable for reclamation, fire breaks, and livestock and wildlife forage on semiarid and saline rangelands. Interest is mounting about this species, but some are concerned that it will become an invader of perennial communities. Only one cultivar (Immigrant) has been released in the United States. Eighty-one...

  9. Foraging Value, Risk Avoidance, and Multiple Control Signals: How the Anterior Cingulate Cortex Controls Value-based Decision-making.

    Science.gov (United States)

    Brown, Joshua W; Alexander, William H

    2017-10-01

    Recent work on the role of the ACC in cognition has focused on choice difficulty, action value, risk avoidance, conflict resolution, and the value of exerting control among other factors. A main underlying question is what are the output signals of ACC, and relatedly, what is their effect on downstream cognitive processes? Here we propose a model of how ACC influences cognitive processing in other brain regions that choose actions. The model builds on the earlier Predicted Response Outcome model and suggests that ACC learns to represent specifically the states in which the potential costs or risks of an action are high, on both short and long timescales. It then uses those cost signals as a basis to bias decisions to minimize losses while maximizing gains. The model simulates both proactive and reactive control signals and accounts for a variety of empirical findings regarding value-based decision-making.

  10. Combustion of animal or vegetable based liquid waste products; Foerbraenning av flytande animaliska/vegetabiliska restprodukter

    Energy Technology Data Exchange (ETDEWEB)

    Wikman, Karin; Berg, Magnus [AaF-Energikonsult AB, Stockholm (Sweden)

    2002-04-01

    In this project experiences from combustion of animal and vegetable based liquid waste products have been compiled. Legal aspects have also been taken into consideration and the potential for this type of fuel on the Swedish energy market has been evaluated. Today the supply of animal and vegetable based liquid waste products for energy production in Sweden is limited. The total production of animal based liquid fat is about 10,000 tonnes annually. The animal based liquid waste products origin mainly from the manufacturing of meat and bone meal. Since meat and bone meal has been banned from use in animal feeds it is possible that the amount of animal based liquid fat will decrease. The vegetable based liquid waste products that are produced in the processing of vegetable fats are today used mainly for internal energy production. This result in limited availability on the commercial market. The potential for import of animal and vegetable based liquid waste products is estimated to be relatively large since the production of this type of waste products is larger in many other countries compared to Sweden. Vegetable oils that are used as food or raw material in industries could also be imported for combustion, but this is not reasonable today since the energy prices are relatively low. Restrictions allow import of SRM exclusively from Denmark. This is today the only limit for increased imports of animal based liquid fat. The restrictions for handle and combustion of animal and vegetable based liquid waste products are partly unclear since this is covered in several regulations that are not easy to interpret. The new directive for combustion of waste (2000/76/EG) is valid for animal based waste products but not for cadaver or vegetable based waste products from provisions industries. This study has shown that more than 27,400 tonnes of animal based liquid waste products and about 6,000 tonnes of vegetable based liquid waste products were used for combustion in Sweden

  11. Oxidative phenols in forage crops containing polyphenol oxidase enzymes.

    Science.gov (United States)

    Parveen, Ifat; Threadgill, Michael D; Moorby, Jon M; Winters, Ana

    2010-02-10

    Polyphenol oxidases (PPOs) are copper-containing enzymes that catalyze oxidation of endogenous monophenols to ortho-dihydroxyaryl compounds and of ortho-dihydroxyaryl compounds to ortho-quinones. Subsequent nucleophilic addition reactions of phenols, amino acids, and proteins with the electrophilic ortho-quinones form brown-, black-, or red-colored secondary products associated with the undesired discolouration of fruit and vegetables. Several important forage plants also exhibit significant PPO activity, and a link with improved efficiency of ruminant production has been established. In ruminant animals, extensive degradation of forage proteins, following consumption, can result in high rates of excretion of nitrogen, which contributes to point-source and diffuse pollution. Reaction of quinones with forage proteins leads to the formation of protein-phenol complexes that are resistant to proteolytic activity during ensilage and during rumen fermentation. Thus, PPO in red clover (Trifolium pratense) has been shown to improve protein utilization by ruminants. While PPO activity has been demonstrated in a number of forage crops, little work has been carried out to identify substrates of PPO, knowledge of which would be beneficial for characterizing this trait in these forages. In general, a wide range of 1,2-dihydroxyarenes can serve as PPO substrates because these are readily oxidized because of the ortho positioning of the hydroxy groups. Naturally occurring phenols isolated from forage crops with PPO activity are reviewed. A large number of phenols, which may be directly or indirectly oxidized as a consequence of PPO activity, have been identified in several forage grass, legume, cereal, and brassica species; these include hydroxybenzoic acids, hydroxycinnamates, and flavonoids. In conclusion, a number of compounds are known or postulated to enable PPO activity in important PPO-expressing forage crops. Targeting the matching of these compounds with PPO activity

  12. producing dairy cows fed conventional forages, wheat straw

    African Journals Online (AJOL)

    Chewing activity, metabolic profile and performance of high- producing dairy cows fed conventional forages, wheat straw or rice straw. ... South African Journal of Animal Science ... Twelve lactating Holstein cows were used in a replicated (n = 4) 3 × 3 Latin square design experiment with three periods of 21 days. Cows were ...

  13. Calculating foraging area using gloal navigation satellite system (GNSS) technology

    Science.gov (United States)

    Adjusting stocking rate to changing forage conditions is a critical part of pro-active range management. In general stocking rate approaches tend to assume more optimal landscape use patterns than will actually occur. Today we can monitor spatio-temporal landscape use on a 24/7 basis using animals...

  14. Bats Can Use Magnetic Compass in Foraging Behavior

    Science.gov (United States)

    Tian, L.; Zhang, B.; Pan, Y.; Zhu, R.

    2016-12-01

    Foraging plays an important role in an animal's ability to survive and reproduce. It is widely recognized that many animals and microorganisms can use geomagnetic compass in migration or homing orientation. Among them, bats, the only flying mammals, can use the magnetic compass in migrating orientations. For instance, we found the migratory microbat, Nyctalus plancyi, could use the magnetic polarity compass in roosting orientation under the strength range at least from a much weaker magnetic field than the present-day geomagnetic field (as low as 10 μT) to up to stronger magnetic field (100 μT). This high sensitivity to magnetic fields intensity may explain how magnetic orientation could have long-term evolved in bats even as the Earth's magnetic field strength varied as the polarity reversed many times in the past. Recently, we carried out foraging behavioral experiments on N. plancyi under various magnetic field conditions. Interestingly, it has shown that, although the auditory including echolocation, or olfactory sense may be the primary methods for seeking food under totally dark circumstance, the bats showed preferred foraging orientations at the magnetic north-south directions when any other sensory cues are insufficient for location of the food. It confirmed that bats could optimally use multiple directional cues including the geomagnetic field in their foraging in field. When bats foraging, they would navigate along the magnetic field direction if there were no direct sensory cues. As it gets close, the direct cues from food would guide them to the food.

  15. Industry and Consumers Awareness for Effective Management of Functional Animal-based Foods in South Korea.

    Science.gov (United States)

    Wi, Seo-Hyun; Park, Jung-Min; Wee, Sung-Hwan; Park, Jae-Woo; Kim, Jin-Man

    2013-12-01

    In recent years, manufacturers of animal-based foods with health claims have encountered difficulties in the labeling of their products because of a lack of regulation on defining the functionality of animal-based foods. Therefore, this study was conducted to establish the basic requirements for the development of a definition for functional animal-based foods by investigating consumer and industry awareness. Survey data were collected from 114 industry representatives and 1,100 consumers. The questions of the survey included items on production status and future production plans, functionality labeling, promotion plans, establishment of definition, the role of the government, consumer perception, and selection of products. The results show that both industry representatives and consumers believe that legislation and the provision of scientific evidence should be improved for the development of a functional animal-based foods market. The results obtained from this study will contribute to consumer trust by supplying correct information and can be utilized in the industry as basic data for the development of functional animal-based food products.

  16. Performance of Underprepared Students in Traditional versus Animation-Based Flipped-Classroom Settings

    Science.gov (United States)

    Gregorius, R. Ma.

    2017-01-01

    Student performance in a flipped classroom with an animation-based content knowledge development system for the bottom third of the incoming first year college students was compared to that in a traditional lecture-based teaching method. 52% of these students withdrew from the traditionally taught General Chemistry course, compared to 22% in a…

  17. Final year veterinary students' attitudes towards small animal dentistry: a questionnaire-based survey.

    Science.gov (United States)

    Perry, R

    2014-09-01

    To investigate the attitudes of final year veterinary students towards small animal dentistry and to examine the teaching received in this subject, both at university and during extra-mural studies. A cross-sectional study of all UK final year veterinary students in 2012 was designed and used by a self-administered Internet-based questionnaire. Six of seven universities participated with 188 student responses. All students felt that it was important or very important for a small animal practitioner to have a broad understanding of dentistry, and that orodental problems were common or very common in small animals. Almost all (99 · 5%) students perceived small animal dentistry as an important or very important subject. Less than 40% of students felt that the teaching had prepared them for entering practice. Over 50% reported that they neither felt confident in discussing orodental problems with clients nor in performing a detailed examination of the oral cavity. Dental problems are perceived by students as frequently encountered in small animal practice. The veterinary surgeon should be adequately trained to detect, diagnose and treat dental disease in small animals and many students feel that their current teaching is inadequate. © 2014 British Small Animal Veterinary Association.

  18. Animal-Based Remedies as Complementary Medicines in the Semi-Arid Region of Northeastern Brazil

    Science.gov (United States)

    Alves, Rômulo R. N.; Barbosa, José A. A.; Santos, Silene L. D. X.; Souto, Wedson M. S.; Barboza, Raynner R. D.

    2011-01-01

    Animals (and their derived products) are essential ingredients in the preparation of many traditional remedies. Despite its prevalence in traditional medical practices worldwide, research on medicinal animals has often been neglected in comparison to medicinal plant research. This work documents the medicinal animals used by a rural community in the semi-arid region, inserted in Caatinga Biome, where 66 respondents provided information on animal species used as medicine, body parts used to prepare the remedies and illnesses to which the remedies were prescribed. We calculated the informant consensus factor to determine the consensus over which species are effective for particular ailments, as well as the species use value to determine the extent of utilization of each species. We recorded the use of 51 animal species as medicines, whose products were recommended for the treatment of 68 illnesses. The informant consensus in the use of many specific remedies is fairly high, giving an additional validity to this folk medicine. Eight species not previously reported as having medicinal use were recorded. The local medicinal fauna is largely based on wild animals, including some endangered species. Given a high proportion of medicinal animals observed in the study area, it is logical to conclude that any conservation strategy should include access to modern health care. PMID:19729490

  19. Sexual segregation in foraging giraffe

    Science.gov (United States)

    Mramba, Rosemary Peter; Mahenya, Obeid; Siyaya, Annetjie; Mathisen, Karen Marie; Andreassen, Harry Peter; Skarpe, Christina

    2017-02-01

    Sexual segregation in giraffe is known to vary between savannas. In this study, we compared sexual segregation in giraffe in one nutrient-rich savanna, the Serengeti National Park, one nutrient-poor, Mikumi National Park, and one medium rich savanna, Arusha National Park, (from here on referred to just by name) based on effects of sexual size dimorphism and related hypotheses. Data were collected in the wet and dry seasons, by driving road transects and making visual observations of browsing giraffe. Additional data were collected from literature (plant chemistry; mammal communities). There was a noticeable difference in browsing by females and males and in browsing between the three savannas. Females browsed a higher diversity of tree species in Serengeti whereas males browsed a higher diversity in Arusha, while the diversity of species browsed in Mikumi was high and about the same in both sexes. Females selected for high concentrations of nitrogen and low concentrations of tannins and phenolics compared to males in Serengeti but selection in Mikumi was more complex. Males browsed higher in the canopy than females in all sites, but the browsing height was generally higher in Serengeti than Mikumi and Arusha. Season had an effect on the browsing height independent of sex in Mikumi, where giraffes browsed higher in the dry season compared to the wet season. Males spent more time browsing per tree compared to females in all three sites; however, browsing time in Mikumi was also affected by season, where giraffes had longer browsing bouts in the wet season compared to the dry season. We suggest that sexual differences in forage requirement and in foraging interacts with differences in tree chemistry and in competing herbivore communities between nutrient rich and nutrient poor savanna in shaping the sexual segregation.

  20. Thermal constraints on foraging of tropical canopy ants.

    Science.gov (United States)

    Spicer, Michelle Elise; Stark, Alyssa Y; Adams, Benjamin J; Kneale, Riley; Kaspari, Michael; Yanoviak, Stephen P

    2017-04-01

    Small cursorial ectotherms risk overheating when foraging in the tropical forest canopy, where the surfaces of unshaded tree branches commonly exceed 50 °C. We quantified the heating and subsequent cooling rates of 11 common canopy ant species from Panama and tested the hypothesis that ant workers stop foraging at temperatures consistent with the prevention of overheating. We created hot experimental "sunflecks" on existing foraging trails of four ant species from different clades and spanning a broad range of body size, heating rate, and critical thermal maxima (CT max ). Different ant species exhibited very different heating rates in the lab, and these differences did not follow trends predicted by body size alone. Experiments with ant models showed that heating rates are strongly affected by color in addition to body size. Foraging workers of all species showed strong responses to heating and consistently abandoned focal sites between 36 and 44 °C. Atta colombica and Azteca trigona workers resumed foraging shortly after heat was removed, but Cephalotes atratus and Dolichoderus bispinosus workers continued to avoid the heated patch even after >5 min of cooling. Large foraging ants (C. atratus) responded slowly to developing thermal extremes, whereas small ants (A. trigona) evacuated sunflecks relatively quickly, and at lower estimated body temperatures than when revisiting previously heated patches. The results of this study provide the first field-based insight into how foraging ants respond behaviorally to the heterogeneous thermal landscape of the tropical forest canopy.

  1. Forage mass and the nutritive value of pastures mixed with forage peanut and red clover

    Directory of Open Access Journals (Sweden)

    Ricardo Lima de Azevedo Junior

    2012-04-01

    Full Text Available The objective of this research was to estimate three pasture-based systems mixed with elephantgrass + spontaneous growth species, annual ryegrass, for pasture-based system 1; elephantgrass + spontaneous growth species + forage peanut, for pasture-based system 2; and elephantgrass + spontaneous growth species + annual ryegrass + red clover, for pasture-based system 3. Elephantgrass was planted in rows 4 m apart from each other. During the cool-season, annual ryegrass was sown in the alleys between the rows of elephantgrass; forage peanut and red clover were sown in the alleys between the elephantgrass according to the respective treatment. The experimental design was totally randomized in the three treatments (pasture-based systems, two replicates (paddocks in completely split-plot time (grazing cycles. Holstein cows receiving 5.5 kg-daily complementary concentrate feed were used in the evaluation. Pre-grazing forage mass, botanical composition and stocking rate were evaluated. Samples of simulated grazing were collected to analyze organic matter (OM, neutral detergent fiber (NDF, crude protein (CP and organic matter in situ digestibility (OMISD. Nine grazing cycles were performed during the experimental period (341 days. The average dry matter values for pre-grazing and stocking rate were 3.34; 3.46; 3.79 t/ha, and 3.28; 3.34; 3.60 AU/ha for each respective pasture-based system. Similar results were observed between the pasture-based systems for OM, NDF, CP and OMISD. Considering forage mass, stocking rate and nutritive value, the pasture-based system intercropped with forage legumes presented better performance.

  2. Digestibilidade aparente dos nutrientes de dietas simplificadas baseadas em forragens para coelhos em crescimento Apparent digestibility of nutrients of simplified diets based on forages for growing rabbits

    Directory of Open Access Journals (Sweden)

    W.M. Ferreira

    2007-04-01

    Full Text Available Avaliaram-se os efeitos de dietas simplificadas à base de forragens sobre a digestibilidade aparente dos nutrientes em coelhos Nova Zelândia branco. As dietas experimentais foram: referência (REF, feno de alfafa (FAL, feno das folhas de rami (FRA, feno das folhas de amoreira (FAM e feno do terço superior da rama da mandioca (FMA. A digestibilidade das dietas foi influenciada pelo tipo de alimento estudado; a FMA apresentou coeficientes de digestibilidade inferiores às demais dietas para todos os princípios nutritivos analisados. Para a dieta FAM, os coeficientes de digestibilidade aparente dos princípios nutritivos foram maiores (P0,05. Os valores estimados de energia digestível (kcal ED/kg MS e proteína digestível (%PD/MS foram, respectivamente, para o feno de alfafa: 2285,27 e 16,04; feno das folhas de rami: 1857,88 e 16,37; feno das folhas de amoreira: 2838,48 e 15,12 e feno do terço superior da mandioca: 2155,55 e 10,57.The effect of simplified diets based on forages on the apparent digestibility in white New Zealand rabbits was evaluated. The treatments were based on the following diets: reference (REF, hay of alfalfa (FAL, hay of rami leaves (FRA, hay of mulberry leaves (FAM and hay of upper to 1/3 aereal part of cassava (FMA. The type of food affected the digestibility of the diets. The FMA diet showed low coefficients of digestibility in comparison to the other diets for all the analyzed nutrients. For the FAM diet the coefficients of apparent digestibility of the nutrients had higher values (P0.05. The estimated values of digestible energy (kcal DE/kg DM and digestible protein (%DP/DM were, respectively, 2285.27 and 16.04 for alfalfa hay, 1857.88 and 16.37 for hay of rami leaves, 2838.48 and 15.12 for hay of mulberry leaves and 2155.55 and 10.57 for hay of upper to 1/3 aereal part of cassava.

  3. Land-based production of animal protein: impacts, efficiency, and sustainability.

    Science.gov (United States)

    Wu, Guoyao; Bazer, Fuller W; Cross, H Russell

    2014-11-01

    Land-based production of high-quality protein by livestock and poultry plays an important role in improving human nutrition, growth, and health, as well as economical and social developments worldwide. With exponential growth of the global population and marked rises in meat consumption per capita, demands for animal-source protein are expected to increase by 72% between 2013 and 2050. This raises concerns about the sustainability and environmental impacts of animal agriculture. An attractive solution to meeting the increasing needs for animal products and mitigating undesired effects of agricultural practices is to enhance the efficiency of animal growth, reproduction, and lactation. Breeding techniques may help achieve this goal, but have only met with limited success. A promising, mechanism-based approach is to optimize the proportion and amounts of amino acids in diets for maximizing whole-body protein synthesis and feed efficiency. Improvements in farm animal productivity will not only decrease the contamination of soils, groundwater, and air by excessive manure, but will also help sustain animal agriculture to produce high-quality protein for the expanding population in the face of diminishing resources. © 2014 New York Academy of Sciences.

  4. Perceptions of a hospital-based animal assisted intervention program: An exploratory study.

    Science.gov (United States)

    Abrahamson, Kathleen; Cai, Yun; Richards, Elizabeth; Cline, Krista; O'Haire, Marguerite E

    2016-11-01

    Research has shown that there are multiple benefits of animal assisted interventions for patients. However, the impact of interaction with these animals in staff is understudied, particularly in the acute care setting, and is thus a novel contribution to the literature on human-animal interaction. The purpose of this qualitative pilot study was to contribute to the body of knowledge surrounding the experiences and perceptions of hospital staff who have participated in a hospital-based animal assisted intervention program. Nine face-to-face semi-structured interviews were conducted (4 staff nurses, 3 support staff members, and 2 hospital volunteers). Five themes emerged from the respondent interviews: (1) descriptions of the therapy dogs; (2) contacts with the dogs at work; (3) connection with the dogs outside of work; (4) benefits; (5) drawbacks. Our findings reflect abundantly positive hospital staff experiences. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Attention in Urban Foraging

    Directory of Open Access Journals (Sweden)

    Malcolm McCullough

    2013-05-01

    Full Text Available This position paper argues how there has to be much more to smart city learning than just wayshowing, and something better as augmented reality than covering the world with instructions. Attention has become something for many people to know better in an age of information superabundance. Embodied cognition explains how the work-ings of attention are not solely a foreground task, as if attention is something to pay. As digital media appear in ever more formats and contexts, their hybrids with physical form increasing influence how habitual engagement with persistent situations creates learning. Ambient information can just add to the distraction by multitasking, or it can support more favorable processes of shifting among different kinds of information with a particular intent. As one word for this latter process, foraging deserves more consideration in smart city learning

  6. The personification of animals: coding of human and nonhuman body parts based on posture and function.

    Science.gov (United States)

    Welsh, Timothy N; McDougall, Laura; Paulson, Stephanie

    2014-09-01

    The purpose of the present research was to determine how humans represent the bodies and limbs of nonhuman mammals based on anatomical and functional properties. To this end, participants completed a series of body-part compatibility tasks in which they responded with a thumb or foot response to the color of a stimulus (red or blue, respectively) presented on different limbs of several animals. Across the studies, this compatibility task was conducted with images of human and nonhuman animals (bears, cows, and monkeys) in bipedal or quadrupedal postures. The results revealed that the coding of the limbs of nonhuman animals is strongly influenced by the posture of the body, but not the functional capacity of the limb. Specifically, body-part compatibility effects were present for both human and nonhuman animals when the figures were in a bipedal posture, but were not present when the animals were in a quadrupedal stance (Experiments 1a-c). Experiments 2a and 2b revealed that the posture-based body-part compatibility effects were not simply a vertical spatial compatibility effect or due to a mismatch between the posture of the body in the image and the participant. These data indicate that nonhuman animals in a bipedal posture are coded with respect to the "human" body representation, whereas nonhuman animals in a quadrupedal posture are not mapped to the human body representation. Overall, these studies provide new insight into the processes through which humans understand, mimic, and learn from the actions of nonhuman animals. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Foraging behavior of bark-foraging birds in the Sierra Nevada

    Science.gov (United States)

    Michael L. Morrison; Kimberly A. With; Irene C. Timossi; William M. Block; Kathleen A. Milne

    1987-01-01

    Data on foraging behavior are often used for examining use of habitat and describing community structure among co-occurring species of birds using the same resource base (e.g., Johnson 1966, Eckhardt 1979, Rusterholz 1981). Differences in tree species, foliage morphology, and bark structure may influence the types of prey taken and the species of bird using the...

  8. Complementary transcriptomic and proteomic analyses reveal regulatory mechanisms of milk protein production in dairy cows consuming different forages

    Science.gov (United States)

    Dai, Wenting; Chen, Qiong; Wang, Quanjuan; White, Robin R.; Liu, Jianxin; Liu, Hongyun

    2017-01-01

    Forage plays a critical role in the milk production of dairy cows; however, the mechanisms regulating bovine milk synthesis in dairy cows fed high forage rations with different basal forage types are not well-understood. In the study, rice straw (RS, low-quality) and alfalfa hay (AH, high-quality) diets were fed to lactating cows to explore how forage quality affected the molecular mechanisms regulating milk production using RNA-seq transcriptomic method with iTRAQ proteomic technique. A total of 554 transcripts (423 increased and 131 decreased) and 517 proteins (231 up-regulated and 286 down-regulated) were differentially expressed in the mammary glands of the two groups. The correlation analysis demonstrated seven proteins (six up-regulated and one down-regulated) had consistent mRNA expression. Functional analysis of the differentially expressed transcripts/proteins suggested that enhanced capacity for energy and fatty acid metabolism, increased protein degradation, reduced protein synthesis, decreased amino acid metabolism and depressed cell growth were related to RS consumption. The results indicated cows consuming RS diets may have had depressed milk protein synthesis because these animals had decreased capacity for protein synthesis, enhanced proteolysis, inefficient energy generation and reduced cell growth. Additional work evaluating RS- and AH-based rations may help better isolate molecular adaptations to low nutrient availability during lactation. PMID:28290485

  9. Complementary transcriptomic and proteomic analyses reveal regulatory mechanisms of milk protein production in dairy cows consuming different forages.

    Science.gov (United States)

    Dai, Wenting; Chen, Qiong; Wang, Quanjuan; White, Robin R; Liu, Jianxin; Liu, Hongyun

    2017-03-14

    Forage plays a critical role in the milk production of dairy cows; however, the mechanisms regulating bovine milk synthesis in dairy cows fed high forage rations with different basal forage types are not well-understood. In the study, rice straw (RS, low-quality) and alfalfa hay (AH, high-quality) diets were fed to lactating cows to explore how forage quality affected the molecular mechanisms regulating milk production using RNA-seq transcriptomic method with iTRAQ proteomic technique. A total of 554 transcripts (423 increased and 131 decreased) and 517 proteins (231 up-regulated and 286 down-regulated) were differentially expressed in the mammary glands of the two groups. The correlation analysis demonstrated seven proteins (six up-regulated and one down-regulated) had consistent mRNA expression. Functional analysis of the differentially expressed transcripts/proteins suggested that enhanced capacity for energy and fatty acid metabolism, increased protein degradation, reduced protein synthesis, decreased amino acid metabolism and depressed cell growth were related to RS consumption. The results indicated cows consuming RS diets may have had depressed milk protein synthesis because these animals had decreased capacity for protein synthesis, enhanced proteolysis, inefficient energy generation and reduced cell growth. Additional work evaluating RS- and AH-based rations may help better isolate molecular adaptations to low nutrient availability during lactation.

  10. Individual foraging strategies reveal niche overlap between endangered galapagos pinnipeds.

    Directory of Open Access Journals (Sweden)

    Stella Villegas-Amtmann

    Full Text Available Most competition studies between species are conducted from a population-level approach. Few studies have examined inter-specific competition in conjunction with intra-specific competition, with an individual-based approach. To our knowledge, none has been conducted on marine top predators. Sympatric Galapagos fur seals (Arctocephalus galapagoensis and sea lions (Zalophus wollebaeki share similar geographic habitats and potentially compete. We studied their foraging niche overlap at Cabo Douglas, Fernandina Island from simultaneously collected dive and movement data to examine spatial and temporal inter- and intra-specific competition. Sea lions exhibited 3 foraging strategies (shallow, intermediate and deep indicating intra-specific competition. Fur seals exhibited one foraging strategy, diving predominantly at night, between 0-80 m depth and mostly at 19-22 h. Most sea lion dives also occurred at night (63%, between 0-40 m, within fur seals' diving depth range. 34% of sea lions night dives occurred at 19-22 h, when fur seals dived the most, but most of them occurred at dawn and dusk, when fur seals exhibited the least amount of dives. Fur seals and sea lions foraging behavior overlapped at 19 and 21 h between 0-30 m depths. Sea lions from the deep diving strategy exhibited the greatest foraging overlap with fur seals, in time (19 h, depth during overlapping time (21-24 m, and foraging range (37.7%. Fur seals foraging range was larger. Cabo Douglas northwest coastal area, region of highest diving density, is a foraging "hot spot" for both species. Fur seals and sea lions foraging niche overlap occurred, but segregation also occurred; fur seals primarily dived at night, while sea lions exhibited night and day diving. Both species exploited depths and areas exclusive to their species. Niche breadth generally increases with environmental uncertainty and decreased productivity. Potential competition between these species could be greater during

  11. Developments in the Transition From Animal Use to Simulation-Based Biomedical Education.

    Science.gov (United States)

    Pawlowski, John B; Feinstein, David M; Gala, Shalin G

    2018-04-18

    There has been a significant shift from the use of animals in biomedical training exercises toward simulation-based education methods. The transition has been driven by technological advances, empirical evidence of improved student outcomes, cost-effectiveness, and a growing concern for the welfare of animals. These factors have spurred policy changes worldwide in how medical and science curricula are delivered. We detail how some of these policy changes evolved and comment on the future direction of simulation-based education and its implications for healthcare providers, instructors, and the general public.

  12. IMPLEMENTATION OF DNA MARKERS TO IMPROVE BREEDING OF FORAGE LEGUMES

    OpenAIRE

    S. Grljušić; M. Tucak; T. Čupić; S. Popović

    2008-01-01

    The low rates of estimated genetic gains in forage legumes breeding have emphasized the need for new breeding methods that would increase efficiency in forage selection and provide reliable improvement. Information on application of molecular methodologies and tools for the enhancement of the current empirical phenotype-based selection moved us toward implementation of DNA markers to our breeding activities. Firstly, attention was given to identification of genetic variability within the fora...

  13. Actions speak louder than words in socially foraging human groups

    OpenAIRE

    Sumner, Seirian; King, Andrew J.

    2011-01-01

    Social foraging in humans has a deep evolutionary history: early hominids searched for dispersed food sources in a patchy, uncertain environment. A fundamental assumption is that social foragers benefit by exchanging information about food sources, in order to make collective decisions based on pooled information. We conducted the first experimental test of this assumption, and showed that, as predicted, communication significantly enhanced group performance. A further, unexpected result was ...

  14. Tandem carrying, a new foraging strategy in ants: description, function, and adaptive significance relative to other described foraging strategies

    Science.gov (United States)

    Guénard, Benoit; Silverman, Jules

    2011-08-01

    An important aspect of social insect biology lies in the expression of collective foraging strategies developed to exploit food. In ants, four main types of foraging strategies are typically recognized based on the intensity of recruitment and the importance of chemical communication. Here, we describe a new type of foraging strategy, "tandem carrying", which is also one of the most simple recruitment strategies, observed in the Ponerinae species Pachycondyla chinensis. Within this strategy, workers are directly carried individually and then released on the food resource by a successful scout. We demonstrate that this recruitment is context dependent and based on the type of food discovered and can be quickly adjusted as food quality changes. We did not detect trail marking by tandem-carrying workers. We conclude by discussing the importance of tandem carrying in an evolutionary context relative to other modes of recruitment in foraging and nest emigration.

  15. Evaluation of Animal-Based Indicators to Be Used in a Welfare Assessment Protocol for Sheep.

    Science.gov (United States)

    Richmond, Susan E; Wemelsfelder, Francoise; de Heredia, Ina Beltran; Ruiz, Roberto; Canali, Elisabetta; Dwyer, Cathy M

    2017-01-01

    Sheep are managed under a variety of different environments (continually outdoors, partially outdoors with seasonal or diurnal variation, continuously indoors) and for different purposes, which makes assessing welfare challenging. This diversity means that resource-based indicators are not particularly useful and, thus, a welfare assessment scheme for sheep, focusing on animal-based indicators, was developed. We focus specifically on ewes, as the most numerous group of sheep present on farm, although many of the indicators may also have relevance to adult male sheep. Using the Welfare Quality ® framework of four Principles and 12 Criteria, we considered the validity, reliability, and feasibility of 46 putative animal-based indicators derived from the literature for these criteria. Where animal-based indicators were potentially unreliably or were not considered feasible, we also considered the resource-based indicators of access to water, stocking density, and floor slipperiness. With the exception of the criteria "Absence of prolonged thirst," we suggest at least one animal-based indicator for each welfare criterion. As a minimum, face validity was available for all indicators; however, for many, we found evidence of convergent validity and discriminant validity (e.g., lameness as measured by gait score, body condition score). The reliability of most of the physical and health measures has been tested in the field and found to be appropriate for use in welfare assessment. However, for the majority of the proposed behavioral indicators (lying synchrony, social withdrawal, postures associated with pain, vocalizations, stereotypy, vigilance, response to surprise, and human approach test), this still needs to be tested. In conclusion, the comprehensive assessment of sheep welfare through largely animal-based measures is supported by the literature through the use of indicators focusing on specific aspects of sheep biology. Further work is required for some indicators

  16. Evaluation of Animal-Based Indicators to Be Used in a Welfare Assessment Protocol for Sheep

    Science.gov (United States)

    Richmond, Susan E.; Wemelsfelder, Francoise; de Heredia, Ina Beltran; Ruiz, Roberto; Canali, Elisabetta; Dwyer, Cathy M.

    2017-01-01

    Sheep are managed under a variety of different environments (continually outdoors, partially outdoors with seasonal or diurnal variation, continuously indoors) and for different purposes, which makes assessing welfare challenging. This diversity means that resource-based indicators are not particularly useful and, thus, a welfare assessment scheme for sheep, focusing on animal-based indicators, was developed. We focus specifically on ewes, as the most numerous group of sheep present on farm, although many of the indicators may also have relevance to adult male sheep. Using the Welfare Quality® framework of four Principles and 12 Criteria, we considered the validity, reliability, and feasibility of 46 putative animal-based indicators derived from the literature for these criteria. Where animal-based indicators were potentially unreliably or were not considered feasible, we also considered the resource-based indicators of access to water, stocking density, and floor slipperiness. With the exception of the criteria “Absence of prolonged thirst,” we suggest at least one animal-based indicator for each welfare criterion. As a minimum, face validity was available for all indicators; however, for many, we found evidence of convergent validity and discriminant validity (e.g., lameness as measured by gait score, body condition score). The reliability of most of the physical and health measures has been tested in the field and found to be appropriate for use in welfare assessment. However, for the majority of the proposed behavioral indicators (lying synchrony, social withdrawal, postures associated with pain, vocalizations, stereotypy, vigilance, response to surprise, and human approach test), this still needs to be tested. In conclusion, the comprehensive assessment of sheep welfare through largely animal-based measures is supported by the literature through the use of indicators focusing on specific aspects of sheep biology. Further work is required for some

  17. Quality of the forage apparently consumed by beef calves in natural grassland under fertilization and oversown with cool season forage species

    Directory of Open Access Journals (Sweden)

    Denise Adelaide Gomes Elejalde

    2012-06-01

    Full Text Available The objective of this study was to evaluate the chemical composition of the forage apparently consumed by steers in a natural grassland on region of Campanha, in Rio Grande do Sul, Brazil, subjected or not to different inputs: NP - natural pasture without inputs; FNP - fertilized natural pasture and INP - improved natural grassland with fertilization and over-seeded with cultivated winter species. Three Angus steers testers and a variable number of regulator animals per experimental unit were utilized in order to maintain 13 kg of DM/100 kg of live weight (LW as forage allowance. One time at each season, hand plucking samples were performed along the daily grazing time simulating forage harvested by the animals. The collected samples after drying and grind were submitted to chemical analysis to determine the forage quality. Except in winter and spring, the values of neutral detergent fiber were higher than the critical value of 550 g/kg of DM, which could limit forage intake, demonstrating that the values of forage on offer provided (15.6; 13.7; 13.5; 15.8 kg of DM/100 kg of LW/day in summer, autumn, winter and spring, respectively were not restrictive to intake. The oversowing of winter cultivated species or fertilization positively alter the degradable fiber content. The seasons had marked influence on the chemical composition of forage apparently consumed; positively increasing some fractions of forage chemical composition in the seasons in which native or cultivated winter species increased their participation. The forage chemical composition is the determining factor in animal performance in natural pasture.

  18. Commensal foraging with Bewick’s Swans Cygnus bewickii doubles instantaneous intake rate of Common Pochards Aythya ferina

    NARCIS (Netherlands)

    Gyimesi, A.; van Lith, B.; Nolet, B.A.

    2012-01-01

    Aquatically foraging Bewick’s Swans Cygnus bewickii have been repeatedly reported to be accompanied by diving ducks, but the exact nature of this relationship is unclear. Based on field observations, we found a strong correlation between the number of foraging swans and the number of foraging Common

  19. Optimal resource allocation to survival and reproduction in parasitic wasps foraging in fragmented habitats.

    Directory of Open Access Journals (Sweden)

    Eric Wajnberg

    Full Text Available Expansion and intensification of human land use represents the major cause of habitat fragmentation. Such fragmentation can have dramatic consequences on species richness and trophic interactions within food webs. Although the associated ecological consequences have been studied by several authors, the evolutionary effects on interacting species have received little research attention. Using a genetic algorithm, we quantified how habitat fragmentation and environmental variability affect the optimal reproductive strategies of parasitic wasps foraging for hosts. As observed in real animal species, the model is based on the existence of a negative trade-off between survival and reproduction resulting from competitive allocation of resources to either somatic maintenance or egg production. We also asked to what degree plasticity along this trade-off would be optimal, when plasticity is costly. We found that habitat fragmentation can indeed have strong effects on the reproductive strategies adopted by parasitoids. With increasing habitat fragmentation animals should invest in greater longevity with lower fecundity; yet, especially in unpredictable environments, some level of phenotypic plasticity should be selected for. Other consequences in terms of learning ability of foraging animals were also observed. The evolutionary consequences of these results are discussed.

  20. Optimal resource allocation to survival and reproduction in parasitic wasps foraging in fragmented habitats.

    Science.gov (United States)

    Wajnberg, Eric; Coquillard, Patrick; Vet, Louise E M; Hoffmeister, Thomas

    2012-01-01

    Expansion and intensification of human land use represents the major cause of habitat fragmentation. Such fragmentation can have dramatic consequences on species richness and trophic interactions within food webs. Although the associated ecological consequences have been studied by several authors, the evolutionary effects on interacting species have received little research attention. Using a genetic algorithm, we quantified how habitat fragmentation and environmental variability affect the optimal reproductive strategies of parasitic wasps foraging for hosts. As observed in real animal species, the model is based on the existence of a negative trade-off between survival and reproduction resulting from competitive allocation of resources to either somatic maintenance or egg production. We also asked to what degree plasticity along this trade-off would be optimal, when plasticity is costly. We found that habitat fragmentation can indeed have strong effects on the reproductive strategies adopted by parasitoids. With increasing habitat fragmentation animals should invest in greater longevity with lower fecundity; yet, especially in unpredictable environments, some level of phenotypic plasticity should be selected for. Other consequences in terms of learning ability of foraging animals were also observed. The evolutionary consequences of these results are discussed.

  1. The opportunity cost of animal based diets exceeds all food losses.

    Science.gov (United States)

    Shepon, Alon; Eshel, Gidon; Noor, Elad; Milo, Ron

    2018-04-10

    Food loss is widely recognized as undermining food security and environmental sustainability. However, consumption of resource-intensive food items instead of more efficient, equally nutritious alternatives can also be considered as an effective food loss. Here we define and quantify these opportunity food losses as the food loss associated with consuming resource-intensive animal-based items instead of plant-based alternatives which are nutritionally comparable, e.g., in terms of protein content. We consider replacements that minimize cropland use for each of the main US animal-based food categories. We find that although the characteristic conventional retail-to-consumer food losses are ≈30% for plant and animal products, the opportunity food losses of beef, pork, dairy, poultry, and eggs are 96%, 90%, 75%, 50%, and 40%, respectively. This arises because plant-based replacement diets can produce 20-fold and twofold more nutritionally similar food per cropland than beef and eggs, the most and least resource-intensive animal categories, respectively. Although conventional and opportunity food losses are both targets for improvement, the high opportunity food losses highlight the large potential savings beyond conventionally defined food losses. Concurrently replacing all animal-based items in the US diet with plant-based alternatives will add enough food to feed, in full, 350 million additional people, well above the expected benefits of eliminating all supply chain food waste. These results highlight the importance of dietary shifts to improving food availability and security. Copyright © 2018 the Author(s). Published by PNAS.

  2. A Web-Based Visualization and Animation Platform for Digital Logic Design

    Science.gov (United States)

    Shoufan, Abdulhadi; Lu, Zheng; Huss, Sorin A.

    2015-01-01

    This paper presents a web-based education platform for the visualization and animation of the digital logic design process. This includes the design of combinatorial circuits using logic gates, multiplexers, decoders, and look-up-tables as well as the design of finite state machines. Various configurations of finite state machines can be selected…

  3. Agent-based Simulation of Reactive, Pro-active, and Social Animal Behaviour

    NARCIS (Netherlands)

    Jonker, C.M.; Treur, J.; Mira, J.

    1998-01-01

    In this paper it is shown how animal behaviour can be simulated in an agent-based manner. Different models are shown for different types of behaviour, varying from purely reactive behaviour to pro-active and social behaviour. The compositional development method for multi-agent systems DESIRE and

  4. Design of graphic and animation in game interface based on cultural ...

    African Journals Online (AJOL)

    Design of graphic and animation in game interface based on cultural value: verification. R.Z. Ramli, N.A.M. Zin, N Sahari Ashaari, M.N. Ismail, S Osman. Abstract. No Abstract. Keywords: game interface; cultural value; hofstede; prototype; eye tracker. Full Text: EMAIL FREE FULL TEXT EMAIL FREE FULL TEXT

  5. Optimal foraging in marine ecosystem models: selectivity, profitability and switching

    DEFF Research Database (Denmark)

    Visser, Andre W.; Fiksen, Ø.

    2013-01-01

    ecological mechanics and evolutionary logic as a solution to diet selection in ecosystem models. When a predator can consume a range of prey items it has to choose which foraging mode to use, which prey to ignore and which ones to pursue, and animals are known to be particularly skilled in adapting...... to the preference functions commonly used in models today. Indeed, depending on prey class resolution, optimal foraging can yield feeding rates that are considerably different from the ‘switching functions’ often applied in marine ecosystem models. Dietary inclusion is dictated by two optimality choices: 1...... by letting predators maximize energy intake or more properly, some measure of fitness where predation risk and cost are also included. An optimal foraging or fitness maximizing approach will give marine ecosystem models a sound principle to determine trophic interactions...

  6. Biosynthesis and regulation of cyanogenic glycoside production in forage plants.

    Science.gov (United States)

    Sun, Zhanmin; Zhang, Kaixuan; Chen, Cheng; Wu, Yanmin; Tang, Yixiong; Georgiev, Milen I; Zhang, Xinquan; Lin, Min; Zhou, Meiliang

    2018-01-01

    The natural products cyanogenic glycosides (CNglcs) are present in various forage plant species including Sorghum spp., Trifolium spp., and Lotus spp. The release of toxic hydrogen cyanide (HCN) from endogenous CNglcs, which is known as cyanogenesis, leads to a serious problem for animal consumption while as defensive secondary metabolites, CNglcs play multiple roles in plant development and responses to adverse environment. Therefore, it is highly important to fully uncover the molecular mechanisms of CNglc biosynthesis and regulation to manipulate the contents of CNglcs in forage plants for fine-tuning the balance between defensive responses and food safety. This review summarizes recent studies on the production, function, polymorphism, and regulation of CNglcs in forage plants, aiming to provide updated knowledge on the ways to manipulate CNglcs for further beneficial economic effects.

  7. Foraging ecology of emperor penguins.

    OpenAIRE

    Zimmer, Ilka; Plötz, Joachim; Bornemann, Horst; Ancel, A.; Hagen, W.

    2006-01-01

    Emperor penguins, Aptenodytes forsteri, play an important role as top predators in high Antarctic marine ecosystems. Long foraging cycles enable chick-rearing birds to range widely in their quest for food. The present study focuses on the critical two month-period before fledging, when maximum growth of chicks occurs and food demand is high at the Pointe Géologie emperor penguin colony of about 3000 breeding pairs. Objectives were to identify the foraging distribution and feeding grounds by s...

  8. Influence of genotype and feeding strategy on pig performance, plasma concentrations of micro nutrients, immune responses and faecal microbiota composition of growing-finishing pigs in a forage-based system

    DEFF Research Database (Denmark)

    Kongsted, Anne Grete; Nørgaard, Jan Værum; Jensen, Søren Krogh

    2015-01-01

    to 15%. There were no significant differences in pig performance between RES+ and RES–. The two breed combinations responded similarly to the reduction in feed allowance with regard to growth performance and feed conversion. Across feeding strategy, the traditional crossbred had 20% lower daily weight...... significantly to the nutritional supply of pigs fed restrictedly with supplementary feed. There are indications that the mineral content of the premix is not needed in a forage-based free-range system but cautious need to be taken with regards to the vitamin A, D, E supply....

  9. The generation algorithm of arbitrary polygon animation based on dynamic correction

    Directory of Open Access Journals (Sweden)

    Hou Ya Wei

    2016-01-01

    Full Text Available This paper, based on the key-frame polygon sequence, proposes a method that makes use of dynamic correction to develop continuous animation. Firstly we use quadratic Bezier curve to interpolate the corresponding sides vector of polygon sequence consecutive frame and realize the continuity of animation sequences. And then, according to Bezier curve characteristic, we conduct dynamic regulation to interpolation parameters and implement the changing smoothness. Meanwhile, we take use of Lagrange Multiplier Method to correct the polygon and close it. Finally, we provide the concrete algorithm flow and present numerical experiment results. The experiment results show that the algorithm acquires excellent effect.

  10. Ingestive and metabolic behavior of beef cattle fed diets with different levels of turnip forage (Rhaphanus sativus cake in replacement to soybean meal

    Directory of Open Access Journals (Sweden)

    Valdecir de Souza Castro

    2014-02-01

    Full Text Available The objective of this study was to assess the effects of five substitution levels of soybean meal by turnip forage cake in the concentrate, on dry matter intake (DM, organic matter (OM, crude protein (CP, ether extract (EE, neutral detergent fiber (NDF and acid detergent fiber (ADF, pH and ammonia nitrogen (N-NH3 in the rumen liquid and plasmatic urea nitrogen (PUN in beef steer. The diets were isoprotein (6.5 % CP and isoenergetic (50.0% TDN, using in natura sugarcane silage as the only forage (85,5 %DM. Five castrated males were used, 1/2 Simental x Nelore cross, with average weight of 610 kg and 36 months old, all fistulated in the rumen. The different levels of replacement were: 0, 25, 50, 75 and 100%, based on CP responsible of soybean meal of ration. Each experimental period lasted 19 days. The experiment was carried out in a 5x5 latin square experimental design, with five animals and five periods. The potential of dry matter intake (%BW and g/kg BW0,75 of turnip forage cake forage was obtained with 27% of replacement in the protean basis in relation to soybean meal, promoting, a maximum intake of 0,217 kg/animal/day, not proportionating alterations in the ruminal dynamic and in the blood.

  11. Variability in individual activity bursts improves ant foraging success.

    Science.gov (United States)

    Campos, Daniel; Bartumeus, Frederic; Méndez, Vicenç; Andrade, José S; Espadaler, Xavier

    2016-12-01

    Using experimental and computational methods, we study the role of behavioural variability in activity bursts (or temporal activity patterns) for individual and collective regulation of foraging in A. senilis ants. First, foraging experiments were carried out under special conditions (low densities of ants and food and absence of external cues or stimuli) where individual-based strategies are most prevalent. By using marked individuals and recording all foraging trajectories, we were then able to precisely quantify behavioural variability among individuals. Our main conclusions are that (i) variability of ant trajectories (turning angles, speed, etc.) is low compared with variability of temporal activity profiles, and (ii) this variability seems to be driven by plasticity of individual behaviour through time, rather than the presence of fixed behavioural stereotypes or specialists within the group. The statistical measures obtained from these experimental foraging patterns are then used to build a general agent-based model (ABM) which includes the most relevant properties of ant foraging under natural conditions, including recruitment through pheromone communication. Using the ABM, we are able to provide computational evidence that the characteristics of individual variability observed in our experiments can provide a functional advantage (in terms of foraging success) to the group; thus, we propose the biological basis underpinning our observations. Altogether, our study reveals the potential utility of experiments under simplified (laboratory) conditions for understanding information-gathering in biological systems. © 2016 The Author(s).

  12. A population-based study of animal component sensitization, asthma, and rhinitis in schoolchildren.

    Science.gov (United States)

    Bjerg, Anders; Winberg, Anna; Berthold, Malin; Mattsson, Lars; Borres, Magnus P; Rönmark, Eva

    2015-09-01

    Animal sensitization is a major determinant of asthma in children. Component-resolved studies of unselected pediatric populations are lacking. The aim was to describe sensitization to animal components and the association with asthma and rhinitis in animal-sensitized schoolchildren. A random sample of 696 children (11-12 years) from a Swedish population-based cohort was tested for sensitization to cat, dog, and horse dander using ImmunoCAP. Sera from animal-sensitized children were further analyzed by microarray including three allergen components from cat, four from dog, and two from horse. The parents completed an expanded ISAAC questionnaire. Of 259 animal-sensitized children (≥0.1 kUA /l), 51% were sensitized to all three, 23% to two, and 25% to one species. Current asthma and asthma symptoms following contact with cats were associated with co-sensitization to Fel d 1 and Fel d 4. This association was seen already at moderate-level sensitization (1-15 ISU) to Fel d 4, at which level most children were sensitized to Fel d 1, as well. In dog-sensitized children, the majority was sensitized to more than one dog component, and co-sensitization to Can f 5 and Can f 1/f 2 conferred the greatest risk for asthma. Sensitization to the highly cross-reactive serum albumins was uncommon and not associated with asthma. Among schoolchildren in northern Sweden, where mite allergy is uncommon, furry animals were the primary perennial sensitizers. Asthma was associated with higher levels of component sensitization, and sensitization to more than one component from the same animal conferred the greatest risk. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  13. Data Analyses and Modelling for Risk Based Monitoring of Mycotoxins in Animal Feed

    Science.gov (United States)

    van der Fels-Klerx, H.J. (Ine); Adamse, Paulien; Punt, Ans; van Asselt, Esther D.

    2018-01-01

    Following legislation, European Member States should have multi-annual control programs for contaminants, such as for mycotoxins, in feed and food. These programs need to be risk based implying the checks are regular and proportional to the estimated risk for animal and human health. This study aimed to prioritize feed products in the Netherlands for deoxynivalenol and aflatoxin B1 monitoring. Historical mycotoxin monitoring results from the period 2007–2016 were combined with data from other sources. Based on occurrence, groundnuts had high priority for aflatoxin B1 monitoring; some feed materials (maize and maize products and several oil seed products) and complete/complementary feed excluding dairy cattle and young animals had medium priority; and all other animal feeds and feed materials had low priority. For deoxynivalenol, maize by-products had a high priority, complete and complementary feed for pigs had a medium priority and all other feed and feed materials a low priority. Also including health consequence estimations showed that feed materials that ranked highest for aflatoxin B1 included sunflower seed and palmkernel expeller/extracts and maize. For deoxynivalenol, maize products were ranked highest, followed by various small grain cereals (products); all other feed materials were of lower concern. Results of this study have proven to be useful in setting up the annual risk based control program for mycotoxins in animal feed and feed materials. PMID:29373559

  14. Data Analyses and Modelling for Risk Based Monitoring of Mycotoxins in Animal Feed

    Directory of Open Access Journals (Sweden)

    H.J. (Ine van der Fels-Klerx

    2018-01-01

    Full Text Available Following legislation, European Member States should have multi-annual control programs for contaminants, such as for mycotoxins, in feed and food. These programs need to be risk based implying the checks are regular and proportional to the estimated risk for animal and human health. This study aimed to prioritize feed products in the Netherlands for deoxynivalenol and aflatoxin B1 monitoring. Historical mycotoxin monitoring results from the period 2007–2016 were combined with data from other sources. Based on occurrence, groundnuts had high priority for aflatoxin B1 monitoring; some feed materials (maize and maize products and several oil seed products and complete/complementary feed excluding dairy cattle and young animals had medium priority; and all other animal feeds and feed materials had low priority. For deoxynivalenol, maize by-products had a high priority, complete and complementary feed for pigs had a medium priority and all other feed and feed materials a low priority. Also including health consequence estimations showed that feed materials that ranked highest for aflatoxin B1 included sunflower seed and palmkernel expeller/extracts and maize. For deoxynivalenol, maize products were ranked highest, followed by various small grain cereals (products; all other feed materials were of lower concern. Results of this study have proven to be useful in setting up the annual risk based control program for mycotoxins in animal feed and feed materials.

  15. Modelling foraging movements of diving predators: a theoretical study exploring the effect of heterogeneous landscapes on foraging efficiency.

    Science.gov (United States)

    Chimienti, Marianna; Bartoń, Kamil A; Scott, Beth E; Travis, Justin M J

    2014-01-01

    Foraging in the marine environment presents particular challenges for air-breathing predators. Information about prey capture rates, the strategies that diving predators use to maximise prey encounter rates and foraging success are still largely unknown and difficult to observe. As well, with the growing awareness of potential climate change impacts and the increasing interest in the development of renewable sources it is unknown how the foraging activity of diving predators such as seabirds will respond to both the presence of underwater structures and the potential corresponding changes in prey distributions. Motivated by this issue we developed a theoretical model to gain general understanding of how the foraging efficiency of diving predators may vary according to landscape structure and foraging strategy. Our theoretical model highlights that animal movements, intervals between prey capture and foraging efficiency are likely to critically depend on the distribution of the prey resource and the size and distribution of introduced underwater structures. For multiple prey loaders, changes in prey distribution affected the searching time necessary to catch a set amount of prey which in turn affected the foraging efficiency. The spatial aggregation of prey around small devices (∼ 9 × 9 m) created a valuable habitat for a successful foraging activity resulting in shorter intervals between prey captures and higher foraging efficiency. The presence of large devices (∼ 24 × 24 m) however represented an obstacle for predator movement, thus increasing the intervals between prey captures. In contrast, for single prey loaders the introduction of spatial aggregation of the resources did not represent an advantage suggesting that their foraging efficiency is more strongly affected by other factors such as the timing to find the first prey item which was found to occur faster in the presence of large devices. The development of this theoretical model represents a useful

  16. MREIT conductivity imaging based on the local harmonic Bz algorithm: Animal experiments

    Science.gov (United States)

    Jeon, Kiwan; Lee, Chang-Ock; Woo, Eung Je; Kim, Hyung Joong; Seo, Jin Keun

    2010-04-01

    From numerous numerical and phantom experiments, MREIT conductivity imaging based on harmonic Bz algorithm shows that it could be yet another useful medical imaging modality. However, in animal experiments, the conventional harmonic Bz algorithm gives poor results near boundaries of problematic regions such as bones, lungs, and gas-filled stomach, and the subject boundary where electrodes are not attached. Since the amount of injected current is low enough for the safety for in vivo animal, the measured Bz data is defected by severe noise. In order to handle such problems, we use the recently developed local harmonic Bz algorithm to obtain conductivity images in our ROI(region of interest) without concerning the defected regions. Furthermore we adopt a denoising algorithm that preserves the ramp structure of Bz data, which informs of the location and size of anomaly. Incorporating these efficient techniques, we provide the conductivity imaging of post-mortem and in vivo animal experiments with high spatial resolution.

  17. Development of pig welfare assessment protocol integrating animal-, environment-, and management-based measures.

    Science.gov (United States)

    Renggaman, Anriansyah; Choi, Hong L; Sudiarto, Sartika Ia; Alasaarela, Laura; Nam, Ok S

    2015-01-01

    Due to increased interest in animal welfare, there is now a need for a comprehensive assessment protocol to be used in intensive pig farming systems. There are two current welfare assessment protocols for pigs: Welfare Quality® Assessment Protocols (applicable in the Europe Union), that mostly focuses on animal-based measures, and the Swine Welfare Assurance Program (applicable in the United States), that mostly focuses on management- and environment-based measures. In certain cases, however, animal-based measures might not be adequate for properly assessing pig welfare status. Similarly, welfare assessment that relies only on environment- and management-based measures might not represent the actual welfare status of pigs. Therefore, the objective of this paper was to develop a new welfare protocol by integrating animal-, environment-, and management-based measures. The background for selection of certain welfare criteria and modification of the scoring systems from existing welfare assessment protocols are described. The developed pig welfare assessment protocol consists of 17 criteria that are related to four main principles of welfare (good feeding, good housing, good health, and appropriate behavior). Good feeding, good housing, and good health were assessed using a 3-point scale: 0 (good welfare), 1 (moderate welfare), and 2 (poor welfare). In certain cases, only a 2-point scale was used: 0 (certain condition is present) or 2 (certain condition is absent). Appropriate behavior was assessed by scan sampling of positive and negative social behaviors based on qualitative behavior assessment and human-animal relationship tests. Modification of the body condition score into a 3-point scale revealed pigs with a moderate body condition (score 1). Moreover, additional criteria such as feed quality confirmed that farms had moderate (score 1) or poor feed quality (score 2), especially those farms located in a high relative humidity region. The developed protocol can be

  18. Plant-based vaccines for animals and humans: recent advances in technology and clinical trials.

    Science.gov (United States)

    Takeyama, Natsumi; Kiyono, Hiroshi; Yuki, Yoshikazu

    2015-09-01

    It has been about 30 years since the first plant engineering technology was established. Although the concept of plant-based pharmaceuticals or vaccines motivates us to develop practicable commercial products using plant engineering, there are some difficulties in reaching the final goal: to manufacture an approved product. At present, the only plant-made vaccine approved by the United States Department of Agriculture is a Newcastle disease vaccine for poultry that is produced in suspension-cultured tobacco cells. The progress toward commercialization of plant-based vaccines takes much effort and time, but several candidate vaccines for use in humans and animals are in clinical trials. This review discusses plant engineering technologies and regulations relevant to the development of plant-based vaccines and provides an overview of human and animal vaccines currently under clinical trials.

  19. Bird and Small Animal Tracking Using a GSM-based System

    Directory of Open Access Journals (Sweden)

    Samuel Matos

    2015-11-01

    Full Text Available This paper describes a prototype of a system designed to track animals, goods or persons. The system is based exclusively on Global System for Mobile Communications (GSM services, which are presently widespread. Its advantages and drawbacks are also discussed. The system itself consists of two independent parts: the base device and the location device. The location device is the part actually attached to the animal, good or person being tracked. It combines reduced size and weight with extended range. The base device can deal with one or more location devices. Its role is to receive the Short Message Service (SMS sent by the location devices and forward them to an application that decodes and stores the location data in a database. Since energy considerations and testing are fundamental in this context, we present detailed energy consumption profiles and the computer applications developed to test the system. We also discuss the results of practical tests with wild and captive birds.

  20. Ruminant Nutrition Symposium: The utility of lipid extracted algae as a protein source in forage or starch-based ruminant diets.

    Science.gov (United States)

    Lodge-Ivey, S L; Tracey, L N; Salazar, A

    2014-04-01

    Two experiments were conducted to determine the influence of lipid extracted algae (LEA) on OM digestibility, N flow, and rumen fermentation. Six samples of LEA were evaluated representing 2 genus of microalgae (Nannochloropsis spp. [n = 3] or Chlorella spp. [n = 3]). Four dual-flow continuous flow fermenters (2,700 mL) were used in a Latin square design to evaluate LEA in forage or concentrate diets compared with soybean meal. Temperature (39 °C), pH, solid (5%/h) and liquid (10%/h) dilution rates, and feed schedule were maintained constant for all experiments. Each experimental period consisted of 6-d adaptation and 4-d sampling periods. There were 7 treatments consisting of 6 different samples of LEA and a soybean meal control (SOY). Diets for Exp.1 were formulated to be 13.0% CP (DM basis) using either soybean meal or LEA and met or exceeded the requirements of a nonpregnant and nonlactating beef cow (450 kg). The forage portion consisted of sorghum-sudan hay (6.4% CP and 46.2% TDN, DM basis) and alfalfa (26.1% CP and 82.3% TDN, DM basis). Concentrate diets used in Exp. 2 met or exceeded the nutrient requirements of a (400 kg) growing steer and contained 85% fine ground corn and included 7% (DM basis) soybean meal or LEA. Data were analyzed as mixed model considering the effect of each LEA compared with soybean meal. Orthogonal contrasts were used to determine the overall effect of LEA genus vs. SOY. True OM digestibility were not influenced by LEA addition to forage diets (P ≥ 0.08) but increased with Chlorella LEA addition to concentrate diets (P ruminant diets. Further research is necessary to fully understand the interactions and consequences of upstream processes and what role algal strain plays in LEA quality.

  1. ANIMAL BEHAVIOR AND WELL-BEING SYMPOSIUM: The Common Swine Industry Audit: Future steps to assure positive on-farm animal welfare utilizing validated, repeatable and feasible animal-based measures.

    Science.gov (United States)

    Pairis-Garcia, M; Moeller, S J

    2017-03-01

    The Common Swine Industry Audit (CSIA) was developed and scientifically evaluated through the combined efforts of a task force consisting of university scientists, veterinarians, pork producers, packers, processers, and retail and food service personnel to provide stakeholders throughout the pork chain with a consistent, reliable, and verifiable system to ensure on-farm swine welfare and food safety. The CSIA tool was built from the framework of the Pork Quality Assurance Plus (PQA Plus) site assessment program with the purpose of developing a single, common audit platform for the U.S. swine industry. Twenty-seven key aspects of swine care are captured and evaluated in CSIA and cover the specific focal areas of animal records, animal observations, facilities, and caretakers. Animal-based measures represent approximately 50% of CSIA evaluation criteria and encompass critical failure criteria, including observation of willful acts of abuse and determination of timely euthanasia. Objective, science-based measures of animal well-being parameters (e.g., BCS, lameness, lesions, hernias) are assessed within CSIA using statistically validated sample sizes providing a detection ability of 1% with 95% confidence. The common CSIA platform is used to identify care issues and facilitate continuous improvement in animal care through a validated, repeatable, and feasible animal-based audit process. Task force members provide continual updates to the CSIA tool with a specific focus toward 1) identification and interpretation of appropriate animal-based measures that provide inherent value to pig welfare, 2) establishment of acceptability thresholds for animal-based measures, and 3) interpretation of CSIA data for use and improvement of welfare within the U.S. swine industry.

  2. Pharmaco-EEG Studies in Animals: A History-Based Introduction to Contemporary Translational Applications.

    Science.gov (United States)

    Drinkenburg, Wilhelmus H I M; Ahnaou, Abdallah; Ruigt, Gé S F

    2015-01-01

    Current research on the effects of pharmacological agents on human neurophysiology finds its roots in animal research, which is also reflected in contemporary animal pharmaco-electroencephalography (p-EEG) applications. The contributions, present value and translational appreciation of animal p-EEG-based applications are strongly interlinked with progress in recording and neuroscience analysis methodology. After the pioneering years in the late 19th and early 20th century, animal p-EEG research flourished in the pharmaceutical industry in the early 1980s. However, around the turn of the millennium the emergence of structurally and functionally revealing imaging techniques and the increasing application of molecular biology caused a temporary reduction in the use of EEG as a window into the brain for the prediction of drug efficacy. Today, animal p-EEG is applied again for its biomarker potential - extensive databases of p-EEG and polysomnography studies in rats and mice hold EEG signatures of a broad collection of psychoactive reference and test compounds. A multitude of functional EEG measures has been investigated, ranging from simple spectral power and sleep-wake parameters to advanced neuronal connectivity and plasticity parameters. Compared to clinical p-EEG studies, where the level of vigilance can be well controlled, changes in sleep-waking behaviour are generally a prominent confounding variable in animal p-EEG studies and need to be dealt with. Contributions of rodent pharmaco-sleep EEG research are outlined to illustrate the value and limitations of such preclinical p-EEG data for pharmacodynamic and chronopharmacological drug profiling. Contemporary applications of p-EEG and pharmaco-sleep EEG recordings in animals provide a common and relatively inexpensive window into the functional brain early in the preclinical and clinical development of psychoactive drugs in comparison to other brain imaging techniques. They provide information on the impact of

  3. Ab initio chemical safety assessment: A workflow based on exposure considerations and non-animal methods.

    Science.gov (United States)

    Berggren, Elisabet; White, Andrew; Ouedraogo, Gladys; Paini, Alicia; Richarz, Andrea-Nicole; Bois, Frederic Y; Exner, Thomas; Leite, Sofia; Grunsven, Leo A van; Worth, Andrew; Mahony, Catherine

    2017-11-01

    We describe and illustrate a workflow for chemical safety assessment that completely avoids animal testing. The workflow, which was developed within the SEURAT-1 initiative, is designed to be applicable to cosmetic ingredients as well as to other types of chemicals, e.g. active ingredients in plant protection products, biocides or pharmaceuticals. The aim of this work was to develop a workflow to assess chemical safety without relying on any animal testing, but instead constructing a hypothesis based on existing data, in silico modelling, biokinetic considerations and then by targeted non-animal testing. For illustrative purposes, we consider a hypothetical new ingredient x as a new component in a body lotion formulation. The workflow is divided into tiers in which points of departure are established through in vitro testing and in silico prediction, as the basis for estimating a safe external dose in a repeated use scenario. The workflow includes a series of possible exit (decision) points, with increasing levels of confidence, based on the sequential application of the Threshold of Toxicological (TTC) approach, read-across, followed by an "ab initio" assessment, in which chemical safety is determined entirely by new in vitro testing and in vitro to in vivo extrapolation by means of mathematical modelling. We believe that this workflow could be applied as a tool to inform targeted and toxicologically relevant in vitro testing, where necessary, and to gain confidence in safety decision making without the need for animal testing.

  4. Salmonella and antimicrobial resistance in an animal-based agriculture river system.

    Science.gov (United States)

    Palhares, Julio Cesar Pascale; Kich, Jalusa D; Bessa, Marjo C; Biesus, Luiza L; Berno, Lais G; Triques, Nelise J

    2014-02-15

    The aim of this study was to examine the Salmonella serovars and antimicrobial resistance within an animal-based agriculture river system. The study area consisted of a 1,345 ha upper part of Pinhal catchment. A total of 384 samples were collected in four years of monitoring. Salmonella was isolated from 241 samples (62.7%), resulting in 324 isolates. The highest number of Salmonella sp. occurred in samples associated with sites with high stoking density animal unit per hectare. It was possible to demonstrate the variability of serovars in the study area: 30 different serovars were found and at least 11 per monitoring site. Thirty-three potentially related isolates were genotyped by PFGE, one major clone was observed in serovar Typhimurium, which occurred in animal feces (swine and bovine), and different sites and samplings proving the cross-contamination and persistence of this specific clone. Among 180 isolates submitted to an antimicrobial susceptibility test, 50.5% were susceptible to all 21 antimicrobials tested and 54 different profiles were found. In the current study, 49.5% of the tested isolates were resistant to at least one antimicrobial, and multi-resistance occurred in 18% of isolates. Results indicate a close interaction between animal-based agriculture, Salmonella, and antimicrobial resistance. Copyright © 2013 Elsevier B.V. All rights reserved.

  5. Risk-based methods for fish and terrestrial animal disease surveillance.

    Science.gov (United States)

    Oidtmann, Birgit; Peeler, Edmund; Lyngstad, Trude; Brun, Edgar; Bang Jensen, Britt; Stärk, Katharina D C

    2013-10-01

    Over recent years there have been considerable methodological developments in the field of animal disease surveillance. The principles of risk analysis were conceptually applied to surveillance in order to further develop approaches and tools (scenario tree modelling) to design risk-based surveillance (RBS) programmes. In the terrestrial animal context, examples of risk-based surveillance have demonstrated the substantial potential for cost saving, and a similar benefit is expected also for aquatic animals. RBS approaches are currently largely absent for aquatic animal diseases. A major constraint in developing RBS designs in the aquatic context is the lack of published data to assist in the design of RBS: this applies to data on (i) the relative risk of farm sites becoming infected due to the presence or absence of a given risk factor; (ii) the sensitivity of diagnostic tests (specificity is often addressed by follow-up investigation and re-testing and therefore less of a concern); (iii) data on the variability of prevalence of infection for fish within a holding unit, between holding units and at farm level. Another constraint is that some of the most basic data for planning surveillance are missing, e.g. data on farm location and animal movements. In Europe, registration or authorisation of fish farms has only recently become a requirement under EU Directive 2006/88. Additionally, the definition of the epidemiological unit (at site or area level) in the context of aquaculture is a challenge due to the often high level of connectedness (mainly via water) of aquaculture facilities with the aquatic environment. This paper provides a review of the principles, methods and examples of RBS in terrestrial, farmed and wild animals. It discusses the special challenges associated with surveillance for aquatic animal diseases (e.g. accessibility of animals for inspection and sampling, complexity of rearing systems) and provides an overview of current developments relevant

  6. Human disturbance provides foraging opportunities for birds in primary subalpine forest

    DEFF Research Database (Denmark)

    DuBay, Shane G.; Hart Reeve, Andrew; Wu, Yongjie

    2017-01-01

    or Cettia major, and Heteroxenicus stellatus. This behavior is likely a modification of pre-existing interspecific foraging associations with pheasants and large mammals in the region. These larger animals disturb the earth and lower vegetation layers upon passage and while foraging, exposing previously......Interspecific foraging associations are well-documented phenomena, characterized by one or more species exploiting the behavior of another species to decrease predation or increase foraging success. In rare cases, birds directly exploit human behavior, but examples of these interactions are limited...... to species that naturally occur in edge, open, or disturbed habitats. With observations and experiments we provide evidence of insectivorous birds exploiting human disturbance in primary subalpine forest in the mountains of southern China, displaying behavioral flexibility to gain novel foraging...

  7. How the foraging decisions of a small ruminant are influenced by past feeding experiences with low-quality food.

    Science.gov (United States)

    Catanese, F; Distel, R A; Fernández, P; Villalba, J J

    2016-05-01

    Feeding experiences with low-quality foods can be improved when these foods are ingested in close temporal association with foods of higher nutritional quality. However, preference for low-quality foods in nature seems to be rather insensitive to past positive experiences and more related to their intrinsic nutritional value. An explanation for this observation is still lacking, mainly because little is known about how herbivores use information about low-quality foods during foraging. Our objective was to provide original information about this issue using a small ruminant (sheep; Ovis aries) as animal model. We manipulated the sheep's experience with a low-quality food (wheat straw) using a conditioning procedure ("oral-delay conditioning procedure"), and then we evaluated the use of this information in a simulated foraging scenario provided with wheat straw and a variable amount of a high-quality food in spatially separated feeding stations. Inclusion of wheat straw into the diet was strongly dependent on the availability of the high-quality food. We observed a threshold level in the availability of the high-quality food, which defined a zone of drastic change in the likelihood of inclusion of the wheat straw into the diet (i.e., acceptance or rejection of wheat straw). This threshold level did not change for sheep with (CS+) or without (CS-) a previous positive experience with wheat straw. However, once foraging conditions stimulated all sheep to start including the wheat straw into the diet (i.e., below the threshold level), the intake of this food was greater by CS+ sheep. This increased intake was not explained by a higher motivation to eat the wheat straw but to a greater amount of time spent foraging this food and less time spent searching for the preferred higher-quality alternative. We discuss these results based on optimal foraging models and learning models of diet selection. Copyright © 2016 Elsevier B.V. All rights reserved.

  8. Does greed help a forager survive?

    Science.gov (United States)

    Bhat, U.; Redner, S.; Bénichou, O.

    2017-06-01

    We investigate the role of greed on the lifetime of a random-walking forager on an initially resource-rich lattice. Whenever the forager lands on a food-containing site, all the food there is eaten and the forager can hop S more steps without food before starving. Upon reaching an empty site, the forager comes one time unit closer to starvation. The forager is also greedy—given a choice to move to an empty or to a food-containing site in its local neighborhood, the forager moves preferentially toward food. Surprisingly, the forager lifetime varies nonmonotonically with greed, with different senses of the nonmonotonicity in one and two dimensions. Also unexpectedly, the forager lifetime in one dimension has a huge peak for very negative greed where the forager is food averse.

  9. Reveal Protein Molecular Structural-Chemical Differences Between Two Types of Winterfat (Forage) Seeds with Physiological Differences in Low Temperature Tolerance Using Synchrotron-Based Fourier Transform Infrared Microspectroscopy

    International Nuclear Information System (INIS)

    Yu, P.; Wang, R.; Bai, Y.

    2005-01-01

    Winterfat (Krascheninnikovia lanata) (forage seed) is a long-lived native shrub with superior forage quality for livestock and wildlife. The objectives of this study were to use advanced synchrotron technology [S-Fourier transform infrared microspectroscopy (FTIR)] as a novel approach to reveal protein molecular structural-chemical differences in terms of protein secondary structures between the two types of winterfat (forage) seeds, which show physiological differences in low-temperature tolerances. This experiment was performed at beamline U10B at the National Synchrotron Light Source NSLS in Brookhaven National Laboratory BNL, U.S. Department of Energy (NSLS-BNL, New York). The results showed that with the synchrotron analytical technique (S-FTIR), the molecular structural-chemical makeup and characteristics of the winterfat seed tissues could be imaged and revealed. The protein secondary structures differed between the large and the small seed tissues. By using the multicomponent peaks modeling method, the results show that the large seeds contained no significant differences (P > 0.05) in percentage of β-sheet (average 37.0%) and α-helix (average 24.1%). However, the large seeds contained a lower (P < 0.05) percentage of β-turns (18.1 vs. 20.1%) and a lower (P < 0.05) ratio of β-turns to α-helices (0.8 vs. 0.9) and β-turns to β-sheets (0.5 vs. 0.6). Our results demonstrate the potential of highly spatially resolved synchrotron-based FTIR microspectroscopy to reveal differences of structural molecular chemistry and protein secondary structures, which are associated with seed size variation and may affect germination behaviors

  10. Adaptive intertemporal preferences in foraging-style environments

    Directory of Open Access Journals (Sweden)

    Michael T. Bixter

    2013-06-01

    Full Text Available Decision makers often face choices between smaller more immediate rewards and larger more delayed rewards. For example, when foraging for food, animals must choose between actions that have varying costs (e.g., effort, duration, energy expenditure and varying benefits (e.g., amount of food intake. The combination of these costs and benefits determine what optimal behavior is. In the present study, we employ a foraging-style task to study how humans make reward-based choices in response to the real-time constraints of a dynamic environment. On each trial participants were presented with two rewards that differed in magnitude and in the delay until their receipt. Because the experiment was of a fixed duration, maximizing earnings required decision makers to determine how to trade off the magnitude and the delay associated with the two rewards on each trial. To evaluate the extent to which participants could adapt to the decision environment, specific task characteristics were manipulated, including reward magnitudes (Experiment 1 and the delay between trials (Experiment 2. Each of these manipulations was designed to alter the pattern of choices made by an optimal decision maker. Several findings are of note. First, different choice strategies were observed with the manipulated environmental constraints. Second, despite contextually-appropriate shifts in behavior between conditions in each experiment, choice patterns deviated from theoretical optimality. In particular, the delays associated with the rewards did not exert a consistent influence on choices as required by exponential discounting. Third, decision makers nevertheless performed surprisingly well in all task environments with any deviations from strict optimality not having particularly deleterious effects on earnings. Taken together, these results suggest that human decision makers are capable of exhibiting intertemporal preferences that reflect a variety of environmental constraints.

  11. Predicting Forage Foodscapes with Spectroscopy and UAV Imagery

    Science.gov (United States)

    Mitchell, J. J.; Olsoy, P.; Forbey, J.; Glenn, N. F.; Burgess, M. A.; Rachlow, J. L.; Shipley, L. A.

    2013-12-01

    A major goal in conservation biology is to predict habitat use by animals. This goal requires methods for identifying and mapping habitat quality features such as concealment, nitrogen (N) and chemical defenses across different spatial scales. Remote sensing has been used for landscape-scale analysis of habitat features to explain the spatial use and selection of habitat by large herbivores. However, studies that directly link specific parameters of habitat quality to selection by wildlife are needed at the microsite-scale before landscape-scale mapping can be validated. Herbivores appear to make foraging decisions based on the nutritional quality of plants. For example, previous research has shown that sagebrush preferentially browsed by pygmy rabbits (Brachylagus idahoensis), a sagebrush specialist mammal, contain relatively higher amounts of crude protein and lower amounts of monoterpenes. Other research has shown that sage grouse (Centrocercus urophasianus) select dwarf sagebrush (Artemisia arbuscula and A. nova) over big sagebrush (A. tridentata subsp wyomingensis) for forage. In this study we examine the use of spectroscopy from the visible to shortwave infrared for predicting sagebrush nutritional quality, as measured by N (crude protein). Predictions are compared across instruments (FOSS NIRSystem 5000 and ASD FieldSpec Pro), sampling methods (i.e., dried ground leaves and fresh whole leaves), and species (dwarf and big sagebrush). We also build a foundation for spatial upscaling from whole leaf and individual shrubs to collective patches in a landscape by acquiring and classifying unmanned aerial vehicle (UAV) imagery in terms of sagebrush food types. The resultant 'foodscape' map concept will ultimately provide a tool for rapid assessment of the dietary quality of sagebrush and facilitate more effective conservation of herbivores that rely on sagebrush for food.

  12. Authorization of Animal Experiments Is Based on Confidence Rather than Evidence of Scientific Rigor

    Science.gov (United States)

    Nathues, Christina; Würbel, Hanno

    2016-01-01

    Accumulating evidence indicates high risk of bias in preclinical animal research, questioning the scientific validity and reproducibility of published research findings. Systematic reviews found low rates of reporting of measures against risks of bias in the published literature (e.g., randomization, blinding, sample size calculation) and a correlation between low reporting rates and inflated treatment effects. That most animal research undergoes peer review or ethical review would offer the possibility to detect risks of bias at an earlier stage, before the research has been conducted. For example, in Switzerland, animal experiments are licensed based on a detailed description of the study protocol and a harm–benefit analysis. We therefore screened applications for animal experiments submitted to Swiss authorities (n = 1,277) for the rates at which the use of seven basic measures against bias (allocation concealment, blinding, randomization, sample size calculation, inclusion/exclusion criteria, primary outcome variable, and statistical analysis plan) were described and compared them with the reporting rates of the same measures in a representative sub-sample of publications (n = 50) resulting from studies described in these applications. Measures against bias were described at very low rates, ranging on average from 2.4% for statistical analysis plan to 19% for primary outcome variable in applications for animal experiments, and from 0.0% for sample size calculation to 34% for statistical analysis plan in publications from these experiments. Calculating an internal validity score (IVS) based on the proportion of the seven measures against bias, we found a weak positive correlation between the IVS of applications and that of publications (Spearman’s rho = 0.34, p = 0.014), indicating that the rates of description of these measures in applications partly predict their rates of reporting in publications. These results indicate that the authorities licensing

  13. Nutrient compensatory foraging in a free-living social insect

    Science.gov (United States)

    Christensen, Keri L.; Gallacher, Anthony P.; Martin, Lizzie; Tong, Desmond; Elgar, Mark A.

    2010-10-01

    The geometric framework model predicts that animal foraging decisions are influenced by their dietary history, with animals targeting a combination of essential nutrients through compensatory foraging. We provide experimental confirmation of nutrient-specific compensatory foraging in a natural, free-living population of social insects by supplementing their diet with sources of protein- or carbohydrate-rich food. Colonies of the ant Iridomyrmex suchieri were provided with feeders containing food rich in either carbohydrate or protein for 6 days, and were then provided with a feeder containing the same or different diet. The patterns of recruitment were consistent with the geometric framework: while feeders with a carbohydrate diet typically attracted more workers than did feeders with protein diet, the difference in recruitment between the two nutrients was smaller if the colonies had had prior access to carbohydrate than protein. Further, fewer ants visited feeders if the colony had had prior access to protein than to carbohydrates, suggesting that the larvae play a role in worker foraging behaviour.

  14. Multidisciplinary and Evidence-based Method for Prioritizing Diseases of Food-producing Animals and Zoonoses

    Science.gov (United States)

    Humblet, Marie-France; Vandeputte, Sébastien; Albert, Adelin; Gosset, Christiane; Kirschvink, Nathalie; Haubruge, Eric; Fecher-Bourgeois, Fabienne; Pastoret, Paul-Pierre

    2012-01-01

    To prioritize 100 animal diseases and zoonoses in Europe, we used a multicriteria decision-making procedure based on opinions of experts and evidence-based data. Forty international experts performed intracategory and intercategory weighting of 57 prioritization criteria. Two methods (deterministic with mean of each weight and probabilistic with distribution functions of weights by using Monte Carlo simulation) were used to calculate a score for each disease. Consecutive ranking was established. Few differences were observed between each method. Compared with previous prioritization methods, our procedure is evidence based, includes a range of fields and criteria while considering uncertainty, and will be useful for analyzing diseases that affect public health. PMID:22469519

  15. MINERAL COMPOSITION OF SOILS, FORAGES AND ANIMAL TISSUE IN THE RIO VERDE REGION, GOIÁS, BRAZIL: IRON AND MANGANESE ESTUDO DA COMPOSIÇÃO MINERAL DE SOLOS, FORRAGENS E TECIDO ANIMAL DE BOVINOS DO MUNICÍPIO DE RIO VERDE, GOIÁS: FERRO E MANGANÊS

    Directory of Open Access Journals (Sweden)

    Eduardo Cavalheiro Jardim

    2007-09-01

    Full Text Available

    A study to determine mineral contents in cattle was conducted in three farms of Rio Verde, State of Goiás, Brazil. Soil, forage and liver samples were collected from each farm (cows and calves. Forage Mn contents were adequate for beef cattle. High levels in Fe on one farm was considered toxic for the grazing cattle. Liver levels in Fe were high in all samples.

    Foram feitas amostragens de solo, forragem e fígado (biópsia em três fazendas representativas do município de Rio Verde, Goiás, com o objetivo de determinar os níveis e possíveis deficiências de minerais na nutrição dos bovinos. Os resultados mostraram que a concentração de manganês nas forragens estão em níveis adequados para bovinos de corte. Entretanto, a concentração de ferro foi superior aos requisitos nutricionais para gado de corte.

  16. Foraging Behavior and Energetics of Albatrosses in Contrasting Breeding Environments

    Directory of Open Access Journals (Sweden)

    Michelle Antolos

    2017-12-01

    Full Text Available Animals can maximize fitness by optimizing energy acquisition through the selection of favorable foraging habitats, but trade-offs exist between time spent in preferred feeding habitats, energetic costs of travel, and reproductive constraints. For pelagic seabirds, geographic distribution of suitable breeding islands can restrict access to marine prey resources and influence foraging strategies. Laysan (Phoebastria immutabilis and black-footed albatrosses (P. nigripes breeding in the Northwest Hawaiian Islands, and Indian yellow-nosed albatrosses (Thalassarche carteri breeding in the Southern Indian Ocean, utilize productive subtropical-subpolar transition zones during their breeding and non-breeding periods, but this marine feature is at a comparatively greater distance for Hawaiian albatrosses during the breeding period due to location of nesting islands. We investigated the foraging behavior and energetics of these three species to evaluate how proximity to preferred marine habitats has influenced their overall foraging strategies. During incubation, all three species traveled to subtropical-subpolar transition zones, however, Hawaiian albatrosses ranged farther to reach this habitat. All species reduced time at sea during brooding, and Hawaiian albatrosses reduced their foraging ranges to distances similar to yellow-nosed albatrosses. As a consequence, Hawaiian albatrosses foraged in the warm, oligotrophic environment of the subtropical gyre during brooding while yellow-nosed albatrosses continued to forage in a subtropical-subpolar transition zone. Landing rates, an indicator of foraging effort, did not differ between reproductive stages and were highly variable within and among species. Hawaiian albatrosses generally spent more time in flight compared to yellow-nosed albatrosses, a strategy that may relate to searching for dispersed and unpredictable prey. Mean absolute field-metabolic rate (FMR was greatest for black-footed albatrosses

  17. Real Time Animation of Trees Based on BBSC in Computer Games

    Directory of Open Access Journals (Sweden)

    Xuefeng Ao

    2009-01-01

    Full Text Available That researchers in the field of computer games usually find it is difficult to simulate the motion of actual 3D model trees lies in the fact that the tree model itself has very complicated structure, and many sophisticated factors need to be considered during the simulation. Though there are some works on simulating 3D tree and its motion, few of them are used in computer games due to the high demand for real-time in computer games. In this paper, an approach of animating trees in computer games based on a novel tree model representation—Ball B-Spline Curves (BBSCs are proposed. By taking advantage of the good features of the BBSC-based model, physical simulation of the motion of leafless trees with wind blowing becomes easier and more efficient. The method can generate realistic 3D tree animation in real-time, which meets the high requirement for real time in computer games.

  18. Multisensory-Based Rehabilitation Approach: Translational Insights from Animal Models to Early Intervention

    Directory of Open Access Journals (Sweden)

    Giulia Purpura

    2017-07-01

    Full Text Available Multisensory processes permit combinations of several inputs, coming from different sensory systems, allowing for a coherent representation of biological events and facilitating adaptation to environment. For these reasons, their application in neurological and neuropsychological rehabilitation has been enhanced in the last decades. Recent studies on animals and human models have indicated that, on one hand multisensory integration matures gradually during post-natal life and development is closely linked to environment and experience and, on the other hand, that modality-specific information seems to do not benefit by redundancy across multiple sense modalities and is more readily perceived in unimodal than in multimodal stimulation. In this review, multisensory process development is analyzed, highlighting clinical effects in animal and human models of its manipulation for rehabilitation of sensory disorders. In addition, new methods of early intervention based on multisensory-based rehabilitation approach and their applications on different infant populations at risk of neurodevelopmental disabilities are discussed.

  19. Columnar transmitter based wireless power delivery system for implantable device in freely moving animals.

    Science.gov (United States)

    Eom, Kyungsik; Jeong, Joonsoo; Lee, Tae Hyung; Lee, Sung Eun; Jun, Sang Bum; Kim, Sung June

    2013-01-01

    A wireless power delivery system is developed to deliver electrical power to the neuroprosthetic devices that are implanted into animals freely moving inside the cage. The wireless powering cage is designed for long-term animal experiments without cumbersome wires for power supply or the replacement of batteries. In the present study, we propose a novel wireless power transmission system using resonator-based inductive links to increase power efficiency and to minimize the efficiency variations. A columnar transmitter coil is proposed to provide lateral uniformity of power efficiency. Using this columnar transmitter coil, only 7.2% efficiency fluctuation occurs from the maximum transmission efficiency of 25.9%. A flexible polymer-based planar type receiver coil is fabricated and assembled with a neural stimulator and an electrode. Using the designed columnar transmitter coil, the implantable device successfully operates while it moves freely inside the cage.

  20. RAPD-based genotyping of Malassezia pachydermatis from Domestic and wild animals

    Directory of Open Access Journals (Sweden)

    Franciele Cristina Kagueyama

    2016-10-01

    Full Text Available Malassezia pachydermatis (M. pachydermatis is a fungus of importance in human and veterinary medicine. Although a part of the normal microbiota, it can sometimes be present in its pathogenic form, particularly causing otitis and dermatitis in animals. Among human beings, it mainly affects immune compromised patients and newborns, causing simple pustulosis, seborrheic dermatitis, tinea versicolor or fungemia. This study aimed to analyze the genomic polymorphism in M. pachydermatis samples isolated from Canis familiaris (domestic dog, Felis catus (domestic cat, and Myrmecophaga tridactyla (giant anteater. Two hundred and fourteen samples were collected and cultured in Sabouraud agar with chloranphenicol (100mg L-1 and incubated at 37 °C for a period of 7 to 10 days. One hundred and sixty six samples that appeared morphologically comparable to yeast cultures were processed for DNA extraction and PCR was performed for a specific region in the Internal Transcribed Spacer (ITS of M. pachydermatis. Among these, seven (4.21% were negative and 159 (95.79% were positive. Of the 159 positive samples, 102 (64.15% were from animals with clinical signs and 57 (35.85% without clinical signs. Fifty-seven samples were selected at random for RAPD-PCR based genotyping and distributed into four genetic groups. Types I and II were more frequent in animals with clinical signs while type III was frequent in healthy animals. Type IV occurred evenly across animals with or without clinical signs. These results indicate differences in pathogenicity of the fungus based on the genotype.

  1. Quadrupedal Gait Generation Based on Human Feeling for Animal Type Robot

    OpenAIRE

    Suzuki, Hidekazu; Nishi, Hitoshi

    2010-01-01

    We proposed a method for generation of an animal gait for a quadrupedal robot. This method optimizes the orbit of the mono-leg using a GA based on the propulsive force and realizes the coordination of each leg on the basis of subjective human feelings. Moreover, we modified the generated gait by additional GA optimization to adapt to the dynamical interference by ground reaction. We checked that AIBO walks straight ahead by proposed method, however, we also checked the centroid fluctuation at...

  2. Animal-based welfare monitoring: using keeper ratings as an assessment tool.

    Science.gov (United States)

    Whitham, Jessica C; Wielebnowski, Nadja

    2009-11-01

    Zoological institutions are in urgent need of identifying and implementing welfare assessment tools that allow for ongoing, quantitative monitoring of individual animal well-being. Although the American Zoological Association's (AZA) Animal Welfare Committee (AWC) promotes the use of such tools in internal review processes, current approaches to institutional welfare assessment are resource-based and outline the resources, environmental parameters and "best practices" recommended for promoting good welfare in a species in general. We highlight the value of incorporating animal-based monitoring tools that capture the individual animal's perspective and subjective experiences, including positive events and feelings, by validating zookeepers' qualitative assessments. We present evidence that, across a variety of species, caretakers' assessments of traits related to the well-being of individual animals can be both reliable and valid. Furthermore, we demonstrate that among researchers investigating the welfare of farm, laboratory, companion and even zoo animals, support already exists for developing and validating instruments that objectively evaluate the qualitative assessments of caretakers. Finally, we outline a process currently being evaluated at Brookfield Zoo for developing, validating and testing a cost-effective, user-friendly monitoring tool that will help to quantify keepers' qualitative assessments of individual well-being and can be integrated into daily operations. This tool (i.e. species-specific Welfare Score Sheets designed through consultation with animal experts) will result in weekly scores of individual well-being that are expected to provide a first indicator of welfare issues in the collection. Specifically, scores can be reviewed during regular workgroup meetings to identify welfare issues proactively, to assess whether particular conditions, practices or events impact individual well-being, and finally, to evaluate the effectiveness of efforts

  3. A Fuzzy Color-Based Approach for Understanding Animated Movies Content in the Indexing Task

    Directory of Open Access Journals (Sweden)

    Vasile Buzuloiu

    2008-04-01

    Full Text Available This paper proposes a method for detecting and analyzing the color techniques used in the animated movies. Each animated movie uses a specific color palette which makes its color distribution one major feature in analyzing the movie content. The color palette is specially tuned by the author in order to convey certain feelings or to express artistic concepts. Deriving semantic or symbolic information from the color concepts or the visual impression induced by the movie should be an ideal way of accessing its content in a content-based retrieval system. The proposed approach is carried out in two steps. The first processing step is the low-level analysis. The movie color content gets represented with several global statistical parameters computed from the movie global weighted color histogram. The second step is the symbolic representation of the movie content. The numerical parameters obtained from the first step are converted into meaningful linguistic concepts through a fuzzy system. They concern mainly the predominant hues of the movie, some of Itten’s color contrasts and harmony schemes, color relationships and color richness. We use the proposed linguistic concepts to link to given animated movies according to their color techniques. In order to make the retrieval task easier, we also propose to represent color properties in a graphical manner which is similar to the color gamut representation. Several tests have been conducted on an animated movie database.

  4. Respiratory nanoparticle-based vaccines and challenges associated with animal models and translation.

    Science.gov (United States)

    Renukaradhya, Gourapura J; Narasimhan, Balaji; Mallapragada, Surya K

    2015-12-10

    Vaccine development has had a huge impact on human health. However, there is a significant need to develop efficacious vaccines for several existing as well as emerging respiratory infectious diseases. Several challenges need to be overcome to develop efficacious vaccines with translational potential. This review focuses on two aspects to overcome some barriers - 1) the development of nanoparticle-based vaccines, and 2) the choice of suitable animal models for respiratory infectious diseases that will allow for translation. Nanoparticle-based vaccines, including subunit vaccines involving synthetic and/or natural polymeric adjuvants and carriers, as well as those based on virus-like particles offer several key advantages to help overcome the barriers to effective vaccine development. These include the ability to deliver combinations of antigens, target the vaccine formulation to specific immune cells, enable cross-protection against divergent strains, act as adjuvants or immunomodulators, allow for sustained release of antigen, enable single dose delivery, and potentially obviate the cold chain. While mouse models have provided several important insights into the mechanisms of infectious diseases, they are often a limiting step in translation of new vaccines to the clinic. An overview of different animal models involved in vaccine research for respiratory infections, with advantages and disadvantages of each model, is discussed. Taken together, advances in nanotechnology, combined with the right animal models for evaluating vaccine efficacy, has the potential to revolutionize vaccine development for respiratory infections. Copyright © 2015 Elsevier B.V. All rights reserved.

  5. Optimal energy window selection of a CZT-based small-animal SPECT for quantitative accuracy

    International Nuclear Information System (INIS)

    Park, Su-Jin; Yu, A. Ram; Choi, Yun Young; Kim, Kyeong Min; Kim, Hee-Joung

    2015-01-01

    Cadmium zinc telluride (CZT)-based small-animal single-photon emission computed tomography (SPECT) has desirable characteristics such as superior energy resolution, but data acquisition for SPECT imaging has been widely performed with a conventional energy window. The aim of this study was to determine the optimal energy window settings for technetium-99 m ( 99m Tc) and thallium-201 ( 201 Tl), the most commonly used isotopes in SPECT imaging, using CZT-based small-animal SPECT for quantitative accuracy. We experimentally investigated quantitative measurements with respect to primary count rate, contrast-to-noise ratio (CNR), and scatter fraction (SF) within various energy window settings using Triumph X-SPECT. The two ways of energy window settings were considered: an on-peak window and an off-peak window. In the on-peak window setting, energy centers were set on the photopeaks. In the off-peak window setting, the ratios of energy differences between the photopeak from the lower- and higher-threshold varied from 4:6 to 3:7. In addition, the energy-window width for 99m Tc varied from 5% to 20%, and that for 201 Tl varied from 10% to 30%. The results of this study enabled us to determine the optimal energy windows for each isotope in terms of primary count rate, CNR, and SF. We selected the optimal energy window that increases the primary count rate and CNR while decreasing SF. For 99m Tc SPECT imaging, the energy window of 138–145 keV with a 5% width and off-peak ratio of 3:7 was determined to be the optimal energy window. For 201 Tl SPECT imaging, the energy window of 64–85 keV with a 30% width and off-peak ratio of 3:7 was selected as the optimal energy window. Our results demonstrated that the proper energy window should be carefully chosen based on quantitative measurements in order to take advantage of desirable characteristics of CZT-based small-animal SPECT. These results provided valuable reference information for the establishment of new protocol for

  6. Optimal energy window selection of a CZT-based small-animal SPECT for quantitative accuracy

    Science.gov (United States)

    Park, Su-Jin; Yu, A. Ram; Choi, Yun Young; Kim, Kyeong Min; Kim, Hee-Joung

    2015-05-01

    Cadmium zinc telluride (CZT)-based small-animal single-photon emission computed tomography (SPECT) has desirable characteristics such as superior energy resolution, but data acquisition for SPECT imaging has been widely performed with a conventional energy window. The aim of this study was to determine the optimal energy window settings for technetium-99 m (99mTc) and thallium-201 (201Tl), the most commonly used isotopes in SPECT imaging, using CZT-based small-animal SPECT for quantitative accuracy. We experimentally investigated quantitative measurements with respect to primary count rate, contrast-to-noise ratio (CNR), and scatter fraction (SF) within various energy window settings using Triumph X-SPECT. The two ways of energy window settings were considered: an on-peak window and an off-peak window. In the on-peak window setting, energy centers were set on the photopeaks. In the off-peak window setting, the ratios of energy differences between the photopeak from the lower- and higher-threshold varied from 4:6 to 3:7. In addition, the energy-window width for 99mTc varied from 5% to 20%, and that for 201Tl varied from 10% to 30%. The results of this study enabled us to determine the optimal energy windows for each isotope in terms of primary count rate, CNR, and SF. We selected the optimal energy window that increases the primary count rate and CNR while decreasing SF. For 99mTc SPECT imaging, the energy window of 138-145 keV with a 5% width and off-peak ratio of 3:7 was determined to be the optimal energy window. For 201Tl SPECT imaging, the energy window of 64-85 keV with a 30% width and off-peak ratio of 3:7 was selected as the optimal energy window. Our results demonstrated that the proper energy window should be carefully chosen based on quantitative measurements in order to take advantage of desirable characteristics of CZT-based small-animal SPECT. These results provided valuable reference information for the establishment of new protocol for CZT-based

  7. Optimal energy window selection of a CZT-based small-animal SPECT for quantitative accuracy

    Energy Technology Data Exchange (ETDEWEB)

    Park, Su-Jin [Department of Radiological Science and Research Institute of Health Science, Yonsei University, Wonju 220-710 (Korea, Republic of); Yu, A. Ram [Laboratory animal center, OSONG Medical Innovation Foundation, Chunguk 363-951 (Korea, Republic of); Department of Nuclear Medicine, College of Medicine, Hanyang University Hospital, Seoul 133-792 (Korea, Republic of); Choi, Yun Young [Department of Nuclear Medicine, College of Medicine, Hanyang University Hospital, Seoul 133-792 (Korea, Republic of); Kim, Kyeong Min [Molecular Imaging Research Center, Korea Institute of Radiological and Medical Sciences, Seoul 139-706 (Korea, Republic of); Kim, Hee-Joung, E-mail: hjk1@yonsei.ac.kr [Department of Radiological Science and Research Institute of Health Science, Yonsei University, Wonju 220-710 (Korea, Republic of)

    2015-05-11

    Cadmium zinc telluride (CZT)-based small-animal single-photon emission computed tomography (SPECT) has desirable characteristics such as superior energy resolution, but data acquisition for SPECT imaging has been widely performed with a conventional energy window. The aim of this study was to determine the optimal energy window settings for technetium-99 m ({sup 99m}Tc) and thallium-201 ({sup 201}Tl), the most commonly used isotopes in SPECT imaging, using CZT-based small-animal SPECT for quantitative accuracy. We experimentally investigated quantitative measurements with respect to primary count rate, contrast-to-noise ratio (CNR), and scatter fraction (SF) within various energy window settings using Triumph X-SPECT. The two ways of energy window settings were considered: an on-peak window and an off-peak window. In the on-peak window setting, energy centers were set on the photopeaks. In the off-peak window setting, the ratios of energy differences between the photopeak from the lower- and higher-threshold varied from 4:6 to 3:7. In addition, the energy-window width for {sup 99m}Tc varied from 5% to 20%, and that for {sup 201}Tl varied from 10% to 30%. The results of this study enabled us to determine the optimal energy windows for each isotope in terms of primary count rate, CNR, and SF. We selected the optimal energy window that increases the primary count rate and CNR while decreasing SF. For {sup 99m}Tc SPECT imaging, the energy window of 138–145 keV with a 5% width and off-peak ratio of 3:7 was determined to be the optimal energy window. For {sup 201}Tl SPECT imaging, the energy window of 64–85 keV with a 30% width and off-peak ratio of 3:7 was selected as the optimal energy window. Our results demonstrated that the proper energy window should be carefully chosen based on quantitative measurements in order to take advantage of desirable characteristics of CZT-based small-animal SPECT. These results provided valuable reference information for the

  8. Combined foraging strategies and soldier behaviour in Nasutitermes aff. coxipoensis (Blattodea: Termitoidea: Termitidae).

    Science.gov (United States)

    Almeida, Camilla S; Cristaldo, Paulo F; Florencio, Daniela F; Cruz, Nayara G; Santos, Abraão A; Oliveira, Alexandre P; Santana, Alisson S; Ribeiro, Efrem J M; Lima, Ana P S; Bacci, Leandro; Araújo, Ana P A

    2016-05-01

    A range of behavioural strategies and sensory abilities allows animals to minimize costs involved in food search. By building a network of tunnels and presenting a large number of soldiers (i.e., trophically dependent individuals), Nasutitermes spp. termites feature behaviours that imply additional costs during this process. Here we evaluated N. aff. coxipoensis foraging strategies focusing on the role of soldiers during foraging. Field experiments were carried out via nests transplantation to dune areas, and laboratory experiments evaluated termite responses to sternal gland chemical signals from workers and soldiers. N. aff. coxipoensis presented primarily nocturnal foraging. Soldiers typically initiated foraging; however, in established trails, the number of workers was always higher than that of soldiers. The number of trails remained constant over time, while the number of tunnels increased linearly over time. A higher proportion of tunnels originated in surrounding areas than directly from the nests. At observation points with tunnels, there were more stationary than walking soldiers; the opposite was true at observation points without tunnels. In mixed groups, the workers chose to follow soldier chemical signals, and in these groups, soldiers were the first to follow trails. Our results allowed us to identify a not common foraging strategy in termite species; which included the establishment of trails followed by construction of tunnels. Such foraging strategies occur predominantly at night and soldiers play a key role in the foraging process. This foraging strategy reported here seems to be employed to optimize energetic gain. Copyright © 2016 Elsevier B.V. All rights reserved.

  9. Risk-based testing of imported animals: A case study for bovine tuberculosis in The Netherlands.

    Science.gov (United States)

    de Vos, Clazien J; van der Goot, Jeanet A; van Zijderveld, Fred G; Swanenburg, Manon; Elbers, Armin R W

    2015-09-01

    In intra-EU trade, the health status of animals is warranted by issuing a health certificate after clinical inspection in the exporting country. This certificate cannot provide guarantee of absence of infection, especially not for diseases with a long incubation period and no overt clinical signs such as bovine tuberculosis (bTB). The Netherlands are officially free from bTB since 1999. However, frequent reintroductions occurred in the past 15 years through importation of infected cattle. Additional testing (AT) of imported cattle could enhance the probability of detecting an imported bTB infection in an early stage. The goal of this study was to evaluate the effectiveness of risk-based AT for bTB in cattle imported into The Netherlands. A generic stochastic import risk model was developed that simulates introduction of infection into an importing country through importation of live animals. Main output parameters are the number of infected animals that is imported (Ninf), the number of infected animals that is detected by testing (Ndet), and the economic losses incurred by importing infected animals (loss). The model was parameterized for bTB. Model calculations were optimized to either maximize Ndet or to minimize loss. Model results indicate that the risk of bTB introduction into The Netherlands is very high. For the current situation in which Dutch health checks on imported cattle are limited to a clinical inspection of a random sample of 5-10% of imported animals, the calculated annual Ninf=99 (median value). Random AT of 8% of all imported cattle results in Ndet=7 (median value), while the median Ndet=75 if the sampling strategy for AT is optimized to maximize Ndet. However, in the latter scenario, loss is more than twice as large as in the current situation, because only calves are tested for which cost of detection is higher than the expected gain of preventing a possible outbreak. When optimizing the sampling strategy for AT to minimize loss, only breeding

  10. Management and assessment of ensiled forages and high-moisture grain.

    Science.gov (United States)

    Seglar, William J; Shaver, Randy D

    2014-11-01

    Various forage and grain crops are grown, harvested, and fed to dairy cattle as ensiled forages or high-moisture grains. Although the nutritional value of hybrids and varieties is influenced by genetic inheritability, the crop growing environment dictates the outcome of forage quality, affecting nutrient digestibility. How the crop is managed based on its stage of harvest maturity and dry matter, along with key ensiling management factors, also determine the nutritional quality of fermented forages and grains. Veterinary practitioners can implement silage quality evaluations as part of a nutritional consultation service to help dairy clients maximize dairy performance and efficiencies. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. Effects of supplementing Leucaena leucocephala and conserved forages from natural pasture on the performance of grazing calves.

    Science.gov (United States)

    Ojo, Victoria Olubunmi A; Aina, Ayobami B J; Fasae, Oladapo A; Oni, Adebayo O; Aderinboye, Ronke Y; Dele, Peter A; Idowu, Oluwaseun J; Adelusi, Oludotun O; Shittu, Olalekan O; Okeniyi, Funmilayo A; Jolaosho, Alaba O

    2014-01-01

    Twelve white Fulani × N'dama cross-bred calves weighing 83.79 ± 1.16 kg were used in an 84-day experiment to investigate the utilization of forage resources from natural grazing land. The experimental diets were sole grazing, grazing + hay, grazing + silage and grazing + Leucaena leucocephala leaves. The calves were divided into four groups of three animals each and were randomly assigned to the four experimental diets. Crude protein (CP) contents of the forages ranged from 59 to 171 g/kg dry matter (DM). Neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents of the forages ranged from 560 to 705 g/kg DM and 363 to 440 g/kg DM, respectively. Significantly (P forage resources. Variations (P forage resources from the natural pasture by the calves was attained on supplementation with conserved forages and L. leucocephala leaves without any deleterious effects on the haematological and serum parameters.

  12. Moving on with foraging theory: incorporating movement decisions into the functional response of a gregarious shorebird.

    Science.gov (United States)

    van Gils, Jan A; van der Geest, Matthijs; De Meulenaer, Brecht; Gillis, Hanneke; Piersma, Theunis; Folmer, Eelke O

    2015-03-01

    rates. We discuss the limitations of Holling's classic functional response model which ignores movement and the limitations of contemporary movement ecological theory that ignores consumer-resource interactions. With the rapid advancement of technologies to track movements of individual foragers at fine spatial scales, the time is ripe to integrate descriptive tracking studies with stochastic movement-based functional response models. © 2014 The Authors. Journal of Animal Ecology © 2014 British Ecological Society.

  13. MicroRNA-based Therapy in Animal Models of Selected Gastrointestinal Cancers

    Directory of Open Access Journals (Sweden)

    Jana Merhautova

    2016-09-01

    Full Text Available Gastrointestinal cancer accounts for the 20 most frequent cancer diseases worldwide and there is a constant urge to bring new therapeutics with new mechanism of action into the clinical practice. Quantity of in vitro and in vivo evidences indicate, that exogenous change in pathologically imbalanced microRNAs (miRNAs is capable of transforming the cancer cell phenotype. This review analyzed preclinical miRNA-based therapy attempts in animal models of gastric, pancreatic, gallbladder, and colorectal cancer. From more than 400 original articles, 26 was found to assess the effect of miRNA mimics, precursors, expression vectors, or inhibitors administered locally or systemically being an approach with relatively high translational potential. We have focused on mapping available information on animal model used (animal strain, cell line, xenograft method, pharmacological aspects (oligonucleotide chemistry, delivery system, posology, route of administration and toxicology assessments. We also summarize findings in the field pharmacokinetics and toxicity of miRNA-based therapy.□

  14. Foraging optimally for home ranges

    Science.gov (United States)

    Mitchell, Michael S.; Powell, Roger A.

    2012-01-01

    Economic models predict behavior of animals based on the presumption that natural selection has shaped behaviors important to an animal's fitness to maximize benefits over costs. Economic analyses have shown that territories of animals are structured by trade-offs between benefits gained from resources and costs of defending them. Intuitively, home ranges should be similarly structured, but trade-offs are difficult to assess because there are no costs of defense, thus economic models of home-range behavior are rare. We present economic models that predict how home ranges can be efficient with respect to spatially distributed resources, discounted for travel costs, under 2 strategies of optimization, resource maximization and area minimization. We show how constraints such as competitors can influence structure of homes ranges through resource depression, ultimately structuring density of animals within a population and their distribution on a landscape. We present simulations based on these models to show how they can be generally predictive of home-range behavior and the mechanisms that structure the spatial distribution of animals. We also show how contiguous home ranges estimated statistically from location data can be misleading for animals that optimize home ranges on landscapes with patchily distributed resources. We conclude with a summary of how we applied our models to nonterritorial black bears (Ursus americanus) living in the mountains of North Carolina, where we found their home ranges were best predicted by an area-minimization strategy constrained by intraspecific competition within a social hierarchy. Economic models can provide strong inference about home-range behavior and the resources that structure home ranges by offering falsifiable, a priori hypotheses that can be tested with field observations.

  15. Comparative Effect of Sole Forage and Mixed Concentrate-Forage ...

    African Journals Online (AJOL)

    There was no statistical (P>0.05) difference in average intake of forage between the two treatment groups. Economically, Treatment 1 proves to be better for the enhancement of body weight in growing rabbits than Treatment 2. Key words: Weaner rabbits,Poultry grower mesh, Tridax procumbens, Feed intake,Body weight ...

  16. A quantum dot-based immunoassay for screening of tylosin and tilmicosin in edible animal tissues.

    Science.gov (United States)

    Le, Tao; Zhu, Liqian; Yang, Xian

    2015-01-01

    A rapid, indirect competitive fluorescence-linked immunosorbent assay (ic-FLISA) based on quantum dots (QDs) as the fluorescent marker was developed for the detection of tylosin and tilmicosin in edible animal tissues. The end point fluorescent detection system was carried out using QDs conjugated with goat anti-mouse secondary antibody. The limits of detection (LODs) for the determination of tylosin and tilmicosin were 0.02 and 0.04 μg kg(-1), respectively. This detection method was used to analyse spiked samples and the recoveries ranged from 83.5% to 98.7% for tylosin and from 81.8% to 98.2% for tilmicosin. In real porcine tissue sample analysis, the results of ic-FLISA were similar to those obtained from an indirect competitive enzyme-linked immunosorbent assay (ic-ELISA) to an HPLC method indicating its potential for tylosin and tilmicosin screening in edible animal tissues.

  17. Enhanced Data Throughput from Animal-Borne Tags via Land Based Argos-Style Receivers

    Science.gov (United States)

    Holland, K.

    2016-02-01

    Increasingly sophisticated electronic tags are now capable of acquiring and archiving large amounts of environmental data (e.g., depth, temperature, oxygen) in addition to providing the geographic locations (tracks) of the tagged animals. However, because Argos satellite availability is sparse in many parts of the world, uploading stored data from animals that are only briefly at the surface can be problematic. We have installed and tested a network of land based Argos style receivers at various locations in the Hawaiian Islands. Data throughput has increased dramatically (sometimes >10 fold) and detection ranges of up to 90 kilometers have been documented. This kind of enhanced data throughput could add significant power to the ATN concept. This paper will provide an overview of the results obtained to date.

  18. Verification of photon attenuation characteristics for 3D printer based small animal lung model

    International Nuclear Information System (INIS)

    Lee, Se Ho; Lee, Seung Wook; Han, Su Chul; Park, Seung Woo

    2016-01-01

    Since it is difficult to measure absorbed dose to mice in vivo, replica mice are mostly used as alternative. In this study, realistic mouse phantom was fabricated by using 3D printer (object500 connex3, Stratasys, USA). Elemental inks as material of 3D printer were selected corresponding to mouse tissue. To represent lung, selected material was partially used with air layer. In order to verify material equivalent, super-flex bolus was simply compared to verify photon attenuation characteristics. In the case of lung, Hounsfield unit (HU) of the phantom were compared with a live mouse. In this study, we fabricated mouse phantom by using 3D printer, and practically verified photon attenuation characteristics. The fabricated phantom shows tissue equivalence as well as similar geometry with live mouse. As more and more growing of 3D printer technique, 3D printer based small preclinical animal phantom would increase reliability of verification of absorbed dose in small animal for preclinical study

  19. Verification of photon attenuation characteristics for 3D printer based small animal lung model

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Se Ho; Lee, Seung Wook [Pusan National University, Busan (Korea, Republic of); Han, Su Chul; Park, Seung Woo [Korea Institute of Radiological and Medical Sciences, Seoul (Korea, Republic of)

    2016-05-15

    Since it is difficult to measure absorbed dose to mice in vivo, replica mice are mostly used as alternative. In this study, realistic mouse phantom was fabricated by using 3D printer (object500 connex3, Stratasys, USA). Elemental inks as material of 3D printer were selected corresponding to mouse tissue. To represent lung, selected material was partially used with air layer. In order to verify material equivalent, super-flex bolus was simply compared to verify photon attenuation characteristics. In the case of lung, Hounsfield unit (HU) of the phantom were compared with a live mouse. In this study, we fabricated mouse phantom by using 3D printer, and practically verified photon attenuation characteristics. The fabricated phantom shows tissue equivalence as well as similar geometry with live mouse. As more and more growing of 3D printer technique, 3D printer based small preclinical animal phantom would increase reliability of verification of absorbed dose in small animal for preclinical study.

  20. Associative effects between forages on feed intake and digestion in ruminants.

    Science.gov (United States)

    Niderkorn, V; Baumont, R

    2009-07-01

    The feeding value of forage mixtures from permanent and temporary multi-species grasslands cannot always be precisely defined. Indeed, the digestibility and feed intake of a combination of forages can differ from the balanced median values calculated from forages considered separately. In order to present an overview of the associative effects between forages on digestion and intake, a literature study was carried out. The associative effects can be studied in a complementary way in vitro to test digestive interactions of a large number of mixtures and to carry out explanatory experiments, and in vivo to investigate intake and digestion at the whole animal scale. We identified three main situations in which interactions between forages can lead to associative effects on intake and digestion: (i) increased intake that can be observed with grass and legume association can be explained by fast digestion of the soluble fraction of legumes, and a higher rate of particle breakdown and passage through the rumen, (ii) increased digestion when a poor forage is supplemented by a high nitrogen content plant can be explained by stimulation of the microbial activity and (iii) modification of digestive processes in the rumen, including proteolysis and methane production when certain bioactive secondary metabolites such as tannins, saponins or polyphenol oxidase are present. According to the type and concentration of these compounds in the diet, the effects can be favourable or unfavourable on intake and digestive parameters. Reported associative effects between forages show a large variability among studies. This reflects the complexity and multiplicity of nutritional situations affecting intake and the rumen function in a given animal. In order to provide more reliable information, further accumulation of data combining in vitro and in vivo studies is required. A better understanding of the associative effects between forages could help to optimise feed use efficiency

  1. Nuisance Ecology: Do Scavenging Condors Exact Foraging Costs on Pumas in Patagonia?

    OpenAIRE

    Elbroch, L. Mark; Wittmer, Heiko U.

    2013-01-01

    Predation risk describes the energetic cost an animal suffers when making a trade off between maximizing energy intake and minimizing threats to its survival. We tested whether Andean condors (Vultur gryphus) influenced the foraging behaviors of a top predator in Patagonia, the puma (Puma concolor), in ways comparable to direct risks of predation for prey to address three questions: 1) Do condors exact a foraging cost on pumas?; 2) If so, do pumas exhibit behaviors indicative of these risks?;...

  2. The MovieClassroom: An Internet Based Application for Students and Instructors to Create Captioned Animations.

    Science.gov (United States)

    Urbano, L.

    2005-12-01

    We have developed and tested an internet based application that facilitates the creation of animations for use in lectures and permits movie production by students in laboratory classes. Animation have been found to be extremely useful educational aids in the geosciences, particularly relating to topics requiring comprehension of geospatial relationships. With this program, instructors are able to assemble and caption animations using an online video clip catalogue and present these movies through a standard internet browser. Captioning increases student comprehension by increasing the multimodality of information delivery. For student use, we developed an exercise for introductory, undergraduate, laboratory class sections that was informed by learning pedagogy, particularly as related to game-based learning. Students were asked to assemble video clips and captions into a coherent movie to explain geospatial concepts, with questions such as "Explain why we have seasons?" The affinity of students to digital technology, particularly computer games and digital media, makes this type of exercise particularly captivating to the typical undergraduate. The opportunity to select and arrange video clips (and add background music) into a unique production offers students a greater degree of ownership of the learning process and allows unique non-linear pathways for accomplishing learning objectives. Use in a laboratory section permitted rapid feedback from the instructor. The application was created using open-sourced software and the database populated with video clips and music contributed by faculty and students under a non-commercial-use license. This tool has the potential to permit the wider dissemination of scientific research results given the increasing use animations for scientific visualization, because it eases the creation of multiple presentations targeted to various audiences and allows user participation in the creation of multimedia.

  3. The drive to strive: goal generation based on current needs

    Directory of Open Access Journals (Sweden)

    Elisabeth A Murray

    2013-06-01

    Full Text Available Hungry animals are influenced by a multitude of different factors when foraging for sustenance. Much of the work on animal foraging has focused on factors relating to the amount of time and energy animals expend searching for and harvesting foods. Models that emphasize such factors have been invaluable in determining when it is beneficial for an animal to search for pastures new. When foraging, however, animals also have to determine how to direct their search. For what food should they forage? There is no point searching for more of a particular food when you are sated from eating it. Here we review work in macaques and humans that has sought to reveal the neural circuits critical for determining the subjective value of different foods and associated objects in our environment and tracking this value over time. There is mounting evidence that a network composed of the orbitofrontal cortex (OFC, amygdala and medial thalamus is critical for linking objects in the environment with food value and adjusting those valuations in real time based on current biological needs. Temporal inactivation studies have revealed that the amygdala and OFC play distinct, but complementary roles in this valuation process. Such a network for determining the subjective value of different foods and, by extension, associated objects, must interact with systems that determine where and for how long to forage. Only by efficiently incorporating these two factors into their decisions will animals be able to achieve maximal fitness.

  4. Forage density effect on sound insulation properties

    DEFF Research Database (Denmark)

    Green, Ole; Tortajada, Vicent Gassó; Gislum, René

    2010-01-01

    One of the main parameters affecting forage management and quality is density. Existing methods used for measuring physical properties of forage involve costly destructive analysis. A frequent and appropriate control of the forage density is required for optimizing the management of silage, hay a...

  5. Synchrotron-based intravenous cerebral angiography in a small animal model

    International Nuclear Information System (INIS)

    Kelly, Michael E; Schueltke, Elisabeth; Fiedler, Stephan; Nemoz, Christian; Guzman, Raphael; Corde, Stephanie; Esteve, Francois; LeDuc, Geraldine; Juurlink, Bernhard H J; Meguro, Kotoo

    2007-01-01

    K-edge digital subtraction angiography (KEDSA), a recently developed synchrotron-based technique, utilizes monochromatic radiation and allows acquisition of high-quality angiography images after intravenous administration of contrast agent. We tested KEDSA for its suitability for intravenous cerebral angiography in an animal model. Adult male New Zealand rabbits were subjected to either angiography with conventional x-ray equipment or synchrotron-based intravenous KEDSA, using an iodine-based contrast agent. Angiography with conventional x-ray equipment after intra-arterial administration of contrast agent demonstrated the major intracranial vessels but no smaller branches. KEDSA was able to visualize the major intracranial vessels as well as smaller branches in both radiography mode (planar images) and tomography mode. Visualization was achieved with as little as 0.5 ml kg -1 of iodinated contrast material. We were able to obtain excellent visualization of the cerebral vasculature in an animal model using intravenous injection of contrast material, using synchrotron-based KEDSA

  6. Personality, foraging behavior and specialization: integrating behavioral and food web ecology at the individual level.

    Science.gov (United States)

    Toscano, Benjamin J; Gownaris, Natasha J; Heerhartz, Sarah M; Monaco, Cristián J

    2016-09-01

    Behavioral traits and diet were traditionally thought to be highly plastic within individuals. This view was espoused in the widespread use of optimality models, which broadly predict that individuals can modify behavioral traits and diet across ecological contexts to maximize fitness. Yet, research conducted over the past 15 years supports an alternative view; fundamental behavioral traits (e.g., activity level, exploration, sociability, boldness and aggressiveness) and diet often vary among individuals and this variation persists over time and across contexts. This phenomenon has been termed animal personality with regard to behavioral traits and individual specialization with regard to diet. While these aspects of individual-level phenotypic variation have been thus far studied in isolation, emerging evidence suggests that personality and individual specialization may covary, or even be causally related. Building on this work, we present the overarching hypothesis that animal personality can drive specialization through individual differences in various aspects of consumer foraging behavior. Specifically, we suggest pathways by which consumer personality traits influence foraging activity, risk-dependent foraging, roles in social foraging groups, spatial aspects of foraging and physiological drivers of foraging, which in turn can lead to consistent individual differences in food resource use. These pathways provide a basis for generating testable hypotheses directly linking animal personality to ecological dynamics, a major goal in contemporary behavioral ecology.

  7. Cloth-based hybridization array system for expanded identification of the animal species origin of derived materials in feeds.

    Science.gov (United States)

    Murphy, Johanna; Armour, Jennifer; Blais, Burton W

    2007-12-01

    A cloth-based hybridization array system (CHAS) previously developed for the detection of animal species for which prohibited materials have been specified (cattle, sheep, goat, elk, and deer) has been expanded to include the detection of animal species for which there are no prohibitions (pig and horse) in Canadian and American animal feeds. Animal species were identified by amplification of mitochondrial DNA sequences by PCR and subsequent hybridization of the amplicons with an array of species-specific oligonucleotide capture probes immobilized on a polyester cloth support, followed by an immunoenzymatic assay of the bound PCR products. The CHAS permitted sensitive and specific detection of meat meals from different animal species blended in a grain-based feed and should provide a useful adjunct to microscopic examination for the identification of prohibited materials in animal feeds.

  8. Auto-Clustering using Particle Swarm Optimization and Bacterial Foraging

    DEFF Research Database (Denmark)

    Rutkowski Olesen, Jakob; Cordero, Jorge; Zeng, Yifeng

    2009-01-01

    This paper presents a hybrid approach for clustering based on particle swarm optimization (PSO) and bacteria foraging algorithms (BFA). The new method AutoCPB (Auto-Clustering based on particle bacterial foraging) makes use of autonomous agents whose primary objective is to cluster chunks of data...... by using simplistic collaboration. Inspired by the advances in clustering using particle swarm optimization, we suggest further improvements. Moreover, we gathered standard benchmark datasets and compared our new approach against the standard K-means algorithm, obtaining promising results. Our hybrid...

  9. Animal-based medicines: biological prospection and the sustainable use of zootherapeutic resources

    Directory of Open Access Journals (Sweden)

    Eraldo M. Costa-Neto

    2005-03-01

    Full Text Available Animals have been used as medicinal resources for the treatment and relieve of a myriad of illnesses and diseases in practically every human culture. Although considered by many as superstition, the pertinence of traditional medicine based on animals cannot be denied since they have been methodically tested by pharmaceutical companies as sources of drugs to the modern medical science. The phenomenon of zootherapy represents a strong evidence of the medicinal use of animal resources. Indeed, drug companies and agribusiness firms have been evaluating animals for decades without paying anything to the countries from where these genetic resources are found. The use of animals' body parts as folk medicines is relevant because it implies additional pressure over critical wild populations. It is argued that many animal species have been overexploited as sources of medicines for the traditional trade. Additionally, animal populations have become depleted or endangered as a result of their use as experimental subjects or animal models. Research on zootherapy should be compatible with the welfare of the medicinal animals, and the use of their by-products should be done in a sustainable way. It is discussed that sustainability is now required as the guiding principle for biological conservation.Os animais são utilizados como recursos medicinais para o tratamento e alívio de um gama de doenças e enfermidades em praticamente toda cultura humana. A pertinência da medicina tradicional baseada em animais, embora considerada como superstição, não deve ser negada uma vez que os animais têm sido testados metodicamente pelas companhias farmacêuticas como fontes de drogas para a ciência médica moderna. O fenômeno da zooterapia representa uma forte evidência do uso medicinal de recursos animais. De fato, as indústrias farmacêuticas e de agronegócios há décadas vêm avaliando animais sem pagar tributos aos países detentores desses recursos gen

  10. Animal Locomotion in Different Mediums

    Indian Academy of Sciences (India)

    IAS Admin

    the direction of moisture and nutrients, animals forage actively by travelling to areas where food is available. However, there is a huge .... with lactate as the end product. In the event of a sprint, lactate. Table 2.Thedifferences between the slow and fast muscle fibres. Parameters. Slow fibres. Fast fibres. Colour. Red. White.

  11. Execution Plans for Cyber Foraging

    DEFF Research Database (Denmark)

    Kristensen, Mads Darø

    2008-01-01

    Cyber foraging helps small devices perform heavy tasks by opportunistically discovering and utilising available resources (such as computation, storage, bandwidth, etc.) held by larger, nearby peers. This offloading is done in an ad-hoc manner, as larger machines will not always be within reach...

  12. Towards a high sensitivity small animal PET system based on CZT detectors (Conference Presentation)

    Science.gov (United States)

    Abbaszadeh, Shiva; Levin, Craig

    2017-03-01

    Small animal positron emission tomography (PET) is a biological imaging technology that allows non-invasive interrogation of internal molecular and cellular processes and mechanisms of disease. New PET molecular probes with high specificity are under development to target, detect, visualize, and quantify subtle molecular and cellular processes associated with cancer, heart disease, and neurological disorders. However, the limited uptake of these targeted probes leads to significant reduction in signal. There is a need to advance the performance of small animal PET system technology to reach its full potential for molecular imaging. Our goal is to assemble a small animal PET system based on CZT detectors and to explore methods to enhance its photon sensitivity. In this work, we reconstruct an image from a phantom using a two-panel subsystem consisting of six CZT crystals in each panel. For image reconstruction, coincidence events with energy between 450 and 570 keV were included. We are developing an algorithm to improve sensitivity of the system by including multiple interaction events.

  13. A reducing trend of fasciolosis in slaughtered animals based on abattoir data in South of Iran.

    Science.gov (United States)

    Kordshooli, Manoochehr Shabani; Solhjoo, Kavous; Armand, Belal; Dowlatkhah, Hamidreza; Jahromi, Masoud Esmi

    2017-04-01

    Fascioliasis is a zoonosis infection caused by the liver trematodes ( Fasciola spp.) which have been considered to be an important disease in livestock. After several large outbreaks, fascioliasis remains one of the serious health concerns of Iran. This study was conducted to evaluate the prevalence and possible trends of fascioliasis in slaughtered animals in South of Iran based on abattoir data during a period of 5 years. The daily records for cattle, sheep, and goats slaughtered in the abattoir were extracted from the archived documents of the recent 5 years (2011-2015) and used as the source of data. The collected data were statistically analyzed for finding any probable correlation between the various factors associated with fasciolosis. Our results showed that 3.44% of all slaughtered animals during 2011-2015 were infected with Fasciola spp. The mean prevalence of fasciolosis for cattle, sheep, and goat was 11.15%, 5.22%, and 2.15%, respectively. In addition, the highest infection rate was in winter (4.02%), and the lowest were entered in summer (2.86%). Our findings showed a reducing trend during the 5 years. Improving the animal husbandry and increasing the awareness through fasciolosis may be a logical explanation for this trend. Since there have been suggested numerous factors associated with the epidemiology of fasciolosis, further studies seem essential for better clarifying the various aspects of fasciolosis in areas.

  14. A reducing trend of fasciolosis in slaughtered animals based on abattoir data in South of Iran

    Directory of Open Access Journals (Sweden)

    Manoochehr Shabani Kordshooli

    2017-04-01

    Full Text Available Aim: Fascioliasis is a zoonosis infection caused by the liver trematodes (Fasciola spp. which have been considered to be an important disease in livestock. After several large outbreaks, fascioliasis remains one of the serious health concerns of Iran. This study was conducted to evaluate the prevalence and possible trends of fascioliasis in slaughtered animals in South of Iran based on abattoir data during a period of 5 years. Materials and Methods: The daily records for cattle, sheep, and goats slaughtered in the abattoir were extracted from the archived documents of the recent 5 years (2011-2015 and used as the source of data. The collected data were statistically analyzed for finding any probable correlation between the various factors associated with fasciolosis. Results: Our results showed that 3.44% of all slaughtered animals during 2011-2015 were infected with Fasciola spp. The mean prevalence of fasciolosis for cattle, sheep, and goat was 11.15%, 5.22%, and 2.15%, respectively. In addition, the highest infection rate was in winter (4.02%, and the lowest were entered in summer (2.86%. Conclusion: Our findings showed a reducing trend during the 5 years. Improving the animal husbandry and increasing the awareness through fasciolosis may be a logical explanation for this trend. Since there have been suggested numerous factors associated with the epidemiology of fasciolosis, further studies seem essential for better clarifying the various aspects of fasciolosis in areas.

  15. How can Smartphone-Based Internet Data Support Animal Ecology Fieldtrip?

    Science.gov (United States)

    Kurniawan, I. S.; Tapilow, F. S.; Hidayat, T.

    2017-09-01

    Identification and classification skills must be owned by the students. In animal ecology course, the identification and classification skills are necessary to study animals. This experimental study aims to describe the identification and classification skills of students on animal ecology field trip to studying various bird species using smartphone-based internet data. Using Involving 63 students divided into 7 groups for each observation station. Data of birds were sampled using line transect method (5000 meters/station). The results showed the identification and classification skills of students are in sufficient categories. Most students have difficulties because of the limitations of data on the internet about birds. In general, students support the use of smartphones in field trip activities. The results of this study can be used as a reference for the development of learning using smartphones in the future by developing application about birds. The outline, smartphones can be used as a method of alternative learning but needs to be developed for some special purposes.

  16. Assessing Herbivore Foraging Behavior with GPS Collars in a Semiarid Grassland

    Directory of Open Access Journals (Sweden)

    Justin D. Derner

    2013-03-01

    Full Text Available Advances in global positioning system (GPS technology have dramatically enhanced the ability to track and study distributions of free-ranging livestock. Understanding factors controlling the distribution of free-ranging livestock requires the ability to assess when and where they are foraging. For four years (2008–2011, we periodically collected GPS and activity sensor data together with direct observations of collared cattle grazing semiarid rangeland in eastern Colorado. From these data, we developed classification tree models that allowed us to discriminate between grazing and non-grazing activities. We evaluated: (1 which activity sensor measurements from the GPS collars were most valuable in predicting cattle foraging behavior, (2 the accuracy of binary (grazing, non-grazing activity models vs. models with multiple activity categories (grazing, resting, traveling, mixed, and (3 the accuracy of models that are robust across years vs. models specific to a given year. A binary classification tree correctly removed 86.5% of the non-grazing locations, while correctly retaining 87.8% of the locations where the animal was grazing, for an overall misclassification rate of 12.9%. A classification tree that separated activity into four different categories yielded a greater misclassification rate of 16.0%. Distance travelled in a 5 minute interval and the proportion of the interval with the sensor indicating a head down position were the two most important variables predicting grazing activity. Fitting annual models of cattle foraging activity did not improve model accuracy compared to a single model based on all four years combined. This suggests that increased sample size was more valuable than accounting for interannual variation in foraging behavior associated with variation in forage production. Our models differ from previous assessments in semiarid rangeland of Israel and mesic pastures in the United States in terms of the value of different

  17. Assessing herbivore foraging behavior with GPS collars in a semiarid grassland.

    Science.gov (United States)

    Augustine, David J; Derner, Justin D

    2013-03-15

    Advances in global positioning system (GPS) technology have dramatically enhanced the ability to track and study distributions of free-ranging livestock. Understanding factors controlling the distribution of free-ranging livestock requires the ability to assess when and where they are foraging. For four years (2008-2011), we periodically collected GPS and activity sensor data together with direct observations of collared cattle grazing semiarid rangeland in eastern Colorado. From these data, we developed classification tree models that allowed us to discriminate between grazing and non-grazing activities. We evaluated: (1) which activity sensor measurements from the GPS collars were most valuable in predicting cattle foraging behavior, (2) the accuracy of binary (grazing, non-grazing) activity models vs. models with multiple activity categories (grazing, resting, traveling, mixed), and (3) the accuracy of models that are robust across years vs. models specific to a given year. A binary classification tree correctly removed 86.5% of the non-grazing locations, while correctly retaining 87.8% of the locations where the animal was grazing, for an overall misclassification rate of 12.9%. A classification tree that separated activity into four different categories yielded a greater misclassification rate of 16.0%. Distance travelled in a 5 minute interval and the proportion of the interval with the sensor indicating a head down position were the two most important variables predicting grazing activity. Fitting annual models of cattle foraging activity did not improve model accuracy compared to a single model based on all four years combined. This suggests that increased sample size was more valuable than accounting for interannual variation in foraging behavior associated with variation in forage production. Our models differ from previous assessments in semiarid rangeland of Israel and mesic pastures in the United States in terms of the value of different activity

  18. Animal Detectives

    Science.gov (United States)

    Mulvey, Bridget; Warnock, Carly

    2015-01-01

    During a two-week inquiry-based 5E learning cycle unit, children made observations and inferences to guide their explorations of animal traits and habitats (Bybee 2014). The children became "animal detectives" by studying a live-feed webcam and digital images of wolves in their natural habitat, reading books and online sources about…

  19. Linking GPS Telemetry Surveys and Scat Analyses Helps Explain Variability in Black Bear Foraging Strategies.

    Science.gov (United States)

    Lesmerises, Rémi; Rebouillat, Lucie; Dussault, Claude; St-Laurent, Martin-Hugues

    2015-01-01

    Studying diet is fundamental to animal ecology and scat analysis, a widespread approach, is considered a reliable dietary proxy. Nonetheless, this method has weaknesses such as non-random sampling of habitats and individuals, inaccurate evaluation of excretion date, and lack of assessment of inter-individual dietary variability. We coupled GPS telemetry and scat analyses of black bears Ursus americanus Pallas to relate diet to individual characteristics and habitat use patterns while foraging. We captured 20 black bears (6 males and 14 females) and fitted them with GPS/Argos collars. We then surveyed GPS locations shortly after individual bear visits and collected 139 feces in 71 different locations. Fecal content (relative dry matter biomass of ingested items) was subsequently linked to individual characteristics (sex, age, reproductive status) and to habitats visited during foraging bouts using Brownian bridges based on GPS locations prior to feces excretion. At the population level, diet composition was similar to what was previously described in studies on black bears. However, our individual-based method allowed us to highlight different intra-population patterns, showing that sex and female reproductive status had significant influence on individual diet. For example, in the same habitats, females with cubs did not use the same food sources as lone bears. Linking fecal content (i.e., food sources) to habitat previously visited by different individuals, we demonstrated a potential differential use of similar habitats dependent on individual characteristics. Females with cubs-of-the-year tended to use old forest clearcuts (6-20 years old) to feed on bunchberry, whereas females with yearling foraged for blueberry and lone bears for ants. Coupling GPS telemetry and scat analyses allows for efficient detection of inter-individual or inter-group variations in foraging strategies and of linkages between previous habitat use and food consumption, even for cryptic

  20. Linking GPS Telemetry Surveys and Scat Analyses Helps Explain Variability in Black Bear Foraging Strategies.

    Directory of Open Access Journals (Sweden)

    Rémi Lesmerises

    Full Text Available Studying diet is fundamental to animal ecology and scat analysis, a widespread approach, is considered a reliable dietary proxy. Nonetheless, this method has weaknesses such as non-random sampling of habitats and individuals, inaccurate evaluation of excretion date, and lack of assessment of inter-individual dietary variability. We coupled GPS telemetry and scat analyses of black bears Ursus americanus Pallas to relate diet to individual characteristics and habitat use patterns while foraging. We captured 20 black bears (6 males and 14 females and fitted them with GPS/Argos collars. We then surveyed GPS locations shortly after individual bear visits and collected 139 feces in 71 different locations. Fecal content (relative dry matter biomass of ingested items was subsequently linked to individual characteristics (sex, age, reproductive status and to habitats visited during foraging bouts using Brownian bridges based on GPS locations prior to feces excretion. At the population level, diet composition was similar to what was previously described in studies on black bears. However, our individual-based method allowed us to highlight different intra-population patterns, showing that sex and female reproductive status had significant influence on individual diet. For example, in the same habitats, females with cubs did not use the same food sources as lone bears. Linking fecal content (i.e., food sources to habitat previously visited by different individuals, we demonstrated a potential differential use of similar habitats dependent on individual characteristics. Females with cubs-of-the-year tended to use old forest clearcuts (6-20 years old to feed on bunchberry, whereas females with yearling foraged for blueberry and lone bears for ants. Coupling GPS telemetry and scat analyses allows for efficient detection of inter-individual or inter-group variations in foraging strategies and of linkages between previous habitat use and food consumption, even

  1. Faecal nitrogen excretion as an approach to estimate forage intake of wethers.

    Science.gov (United States)

    Kozloski, G V; Oliveira, L; Poli, C H E C; Azevedo, E B; David, D B; Ribeiro Filho, H M N; Collet, S G

    2014-08-01

    Data from twenty-two digestibility trials were compiled to examine the relationship between faecal N concentration and organic matter (OM) digestibility (OMD), and between faecal N excretion and OM intake (OMI) by wethers fed tropical or temperate forages alone or with supplements. Data set was grouped by diet type as follows: only tropical grass (n = 204), only temperate grass (n = 160), tropical grass plus supplement (n = 216), temperate grass plus supplement (n = 48), tropical grass plus tropical legume (n = 60) and temperate grass with ruminal infusion of tannins (n = 16). Positive correlation between OMD and either total faecal N concentration (Nfc, % of OM) or metabolic faecal N concentration (Nmetfc, % of OM) was significant for most diet types. Exceptions were the diet that included a tropical legume, where both relationships were negative, and the diet that included tannin extract, where the correlation between OMD and Nfc was not significant. Pearson correlation and linear regressions between OM intake (OMI, g/day) and faecal N excretion (Nf, g/day) were significant for all diet types. When OMI was estimated from the OM faecal excretion and Nfc-based OMD values, the linear comparison between observed and estimated OMI values showed intercept different from 0 and slope different from 1. When OMI was estimated using the Nf-based linear regressions, the linear comparison between observed and estimated OMI values showed neither intercept different from 0 nor slope different from 1. Both linear comparisons showed similar R(2) values (i.e. 0.78 vs. 0.79). In conclusion, linear equations are suitable for directly estimating OM intake by wethers, fed only forage or forage plus supplements, from the amount of N excreted in faeces. The use of this approach in experiments with grazing wethers has the advantage of accounting for individual variations in diet selection and digestion processes and precludes the use of techniques to estimate forage

  2. Linking GPS Telemetry Surveys and Scat Analyses Helps Explain Variability in Black Bear Foraging Strategies

    Science.gov (United States)

    Lesmerises, Rémi; Rebouillat, Lucie; Dussault, Claude; St-Laurent, Martin-Hugues

    2015-01-01

    Studying diet is fundamental to animal ecology and scat analysis, a widespread approach, is considered a reliable dietary proxy. Nonetheless, this method has weaknesses such as non-random sampling of habitats and individuals, inaccurate evaluation of excretion date, and lack of assessment of inter-individual dietary variability. We coupled GPS telemetry and scat analyses of black bears Ursus americanus Pallas to relate diet to individual characteristics and habitat use patterns while foraging. We captured 20 black bears (6 males and 14 females) and fitted them with GPS/Argos collars. We then surveyed GPS locations shortly after individual bear visits and collected 139 feces in 71 different locations. Fecal content (relative dry matter biomass of ingested items) was subsequently linked to individual characteristics (sex, age, reproductive status) and to habitats visited during foraging bouts using Brownian bridges based on GPS locations prior to feces excretion. At the population level, diet composition was similar to what was previously described in studies on black bears. However, our individual-based method allowed us to highlight different intra-population patterns, showing that sex and female reproductive status had significant influence on individual diet. For example, in the same habitats, females with cubs did not use the same food sources as lone bears. Linking fecal content (i.e., food sources) to habitat previously visited by different individuals, we demonstrated a potential differential use of similar habitats dependent on individual characteristics. Females with cubs-of-the-year tended to use old forest clearcuts (6–20 years old) to feed on bunchberry, whereas females with yearling foraged for blueberry and lone bears for ants. Coupling GPS telemetry and scat analyses allows for efficient detection of inter-individual or inter-group variations in foraging strategies and of linkages between previous habitat use and food consumption, even for cryptic

  3. Development of an ultrahigh resolution Si-PM based PET system for small animals

    Science.gov (United States)

    Yamamoto, Seiichi; Watabe, Hiroshi; Kanai, Yasukazu; Watabe, Tadashi; Kato, Katsuhiko; Hatazawa, Jun

    2013-11-01

    Since a high resolution PET system is needed for small animal imaging, especially for mouse studies, we developed a new small animal PET system that decreased the size of the scintillators to less than 1 mm. Our developed PET system used 0.5 × 0.7 × 5 mm3 LYSO pixels arranged in an 11 × 13 matrix to form a block with a 0.1 mm BaSO4 reflector between the pixels. Two LYSO blocks were optically coupled to two optical fiber based angled image guides. These LYSO blocks and image guides were coupled to a Si-PM array (Hamamatsu MPPC S11064-050P) to form a block detector. Eight block detectors (16 LYSO blocks) were arranged in a 34 mm inner diameter ring to form a small animal PET system. The block detector showed good separation for the 22 × 13 LYSO pixels in the two-dimensional position histogram. The energy resolution was 20% full-with at half-maximum (FWHM) for 511 keV gamma photons. The transaxial resolution reconstructed by filtered backprojection was 0.71 to 0.75 mm FWHM and the axial resolution was 0.70 mm. The point source sensitivity was 0.24% at the central axial field-of-view. High resolution mouse images were obtained using our PET system. The developed ultrahigh resolution PET system showed attractive images for small animal studies and has a potential to provide new findings in molecular imaging researches.

  4. Development of an ultrahigh resolution Si-PM based PET system for small animals

    International Nuclear Information System (INIS)

    Yamamoto, Seiichi; Kato, Katsuhiko; Watabe, Hiroshi; Kanai, Yasukazu; Watabe, Tadashi; Hatazawa, Jun

    2013-01-01

    Since a high resolution PET system is needed for small animal imaging, especially for mouse studies, we developed a new small animal PET system that decreased the size of the scintillators to less than 1 mm. Our developed PET system used 0.5 × 0.7 × 5 mm 3 LYSO pixels arranged in an 11 × 13 matrix to form a block with a 0.1 mm BaSO 4 reflector between the pixels. Two LYSO blocks were optically coupled to two optical fiber based angled image guides. These LYSO blocks and image guides were coupled to a Si-PM array (Hamamatsu MPPC S11064–050P) to form a block detector. Eight block detectors (16 LYSO blocks) were arranged in a 34 mm inner diameter ring to form a small animal PET system. The block detector showed good separation for the 22 × 13 LYSO pixels in the two-dimensional position histogram. The energy resolution was 20% full-with at half-maximum (FWHM) for 511 keV gamma photons. The transaxial resolution reconstructed by filtered backprojection was 0.71 to 0.75 mm FWHM and the axial resolution was 0.70 mm. The point source sensitivity was 0.24% at the central axial field-of-view. High resolution mouse images were obtained using our PET system. The developed ultrahigh resolution PET system showed attractive images for small animal studies and has a potential to provide new findings in molecular imaging researches. (paper)

  5. Attenuation correction for freely moving small animal brain PET studies based on a virtual scanner geometry

    International Nuclear Information System (INIS)

    Angelis, G I; Kyme, A Z; Ryder, W J; Fulton, R R; Meikle, S R

    2014-01-01

    Attenuation correction in positron emission tomography brain imaging of freely moving animals is a very challenging problem since the torso of the animal is often within the field of view and introduces a non negligible attenuating factor that can degrade the quantitative accuracy of the reconstructed images. In the context of unrestrained small animal imaging, estimation of the attenuation correction factors without the need for a transmission scan is highly desirable. An attractive approach that avoids the need for a transmission scan involves the generation of the hull of the animal’s head based on the reconstructed motion corrected emission images. However, this approach ignores the attenuation introduced by the animal’s torso. In this work, we propose a virtual scanner geometry which moves in synchrony with the animal’s head and discriminates between those events that traversed only the animal’s head (and therefore can be accurately compensated for attenuation) and those that might have also traversed the animal’s torso. For each recorded pose of the animal’s head a new virtual scanner geometry is defined and therefore a new system matrix must be calculated leading to a time-varying system matrix. This new approach was evaluated on phantom data acquired on the microPET Focus 220 scanner using a custom-made phantom and step-wise motion. Results showed that when the animal’s torso is within the FOV and not appropriately accounted for during attenuation correction it can lead to bias of up to 10% . Attenuation correction was more accurate when the virtual scanner was employed leading to improved quantitative estimates (bias < 2%), without the need to account for the attenuation introduced by the extraneous compartment. Although the proposed method requires increased computational resources, it can provide a reliable approach towards quantitatively accurate attenuation correction for freely moving animal studies. (paper)

  6. Extreme positive allometry of animal adhesive pads and the size limits of adhesion-based climbing.

    Science.gov (United States)

    Labonte, David; Clemente, Christofer J; Dittrich, Alex; Kuo, Chi-Yun; Crosby, Alfred J; Irschick, Duncan J; Federle, Walter

    2016-02-02

    Organismal functions are size-dependent whenever body surfaces supply body volumes. Larger organisms can develop strongly folded internal surfaces for enhanced diffusion, but in many cases areas cannot be folded so that their enlargement is constrained by anatomy, presenting a problem for larger animals. Here, we study the allometry of adhesive pad area in 225 climbing animal species, covering more than seven orders of magnitude in weight. Across all taxa, adhesive pad area showed extreme positive allometry and scaled with weight, implying a 200-fold increase of relative pad area from mites to geckos. However, allometric scaling coefficients for pad area systematically decreased with taxonomic level and were close to isometry when evolutionary history was accounted for, indicating that the substantial anatomical changes required to achieve this increase in relative pad area are limited by phylogenetic constraints. Using a comparative phylogenetic approach, we found that the departure from isometry is almost exclusively caused by large differences in size-corrected pad area between arthropods and vertebrates. To mitigate the expected decrease of weight-specific adhesion within closely related taxa where pad area scaled close to isometry, data for several taxa suggest that the pads' adhesive strength increased for larger animals. The combination of adjustments in relative pad area for distantly related taxa and changes in adhesive strength for closely related groups helps explain how climbing with adhesive pads has evolved in animals varying over seven orders of magnitude in body weight. Our results illustrate the size limits of adhesion-based climbing, with profound implications for large-scale bio-inspired adhesives.

  7. Can we measure carrying capacity with foraging behavior?

    Science.gov (United States)

    Morris, Douglas W; Mukherjee, Shomen

    2007-03-01

    Carrying capacity is one of the most important, yet least understood and rarely estimated, parameters in population management and modeling. A simple behavioral metric of carrying capacity would advance theory, conservation, and management of biological populations. Such a metric should be possible because behavior is finely attuned to variation in environment including population density. We connect optimal foraging theory with population dynamics and life history to develop a simple model that predicts this sort of adaptive density-dependent change in food consumption. We then confirm the model's unexpected and manifold predictions with field experiments. The theory predicts reproductive thresholds that alter the marginal value of energy as well as the value of time. Both effects cause a pronounced discontinuity in quitting-harvest rate that we revealed with foraging experiments. Red-backed voles maintained across a range of high densities foraged at a lower density-dependent rate than the same animals exposed to low-density treatments. The change in harvest rate is diagnostic of populations that exceed their carrying capacity. Ecologists, conservation biologists, and wildlife managers may thus be able to use simple and efficient foraging experiments to estimate carrying capacity and habitat quality.

  8. The drought calculator: decision support tool for predicting forage growth during drought

    Science.gov (United States)

    The Drought Calculator (DC), a spreadsheet-based decision support system, was developed to help ranchers and range managers predict reductions in forage production due to drought. Forage growth potential (FGP) is predicted as a weighted average of monthly precipitation during the spring. Precipita...

  9. Nutritive value of mule deer forages on ponderosa pine summer range in Arizona

    Science.gov (United States)

    P. J. Urness; D. J. Neff; R. K. Watkins

    1975-01-01

    Chemical analyses and apparent in vitro dry matter digestibilities were obtained for mule deer (Odocoileus hemionus) forages appearing in monthly diets. Relative values among individual forage species were calculated based upon nutrient contents and percentage composition in the diet. These data provide land managers with the means to more precisely assess some impacts...

  10. From the Lab Bench: Should we be concerned with the digestible energy in grazed forages?

    Science.gov (United States)

    An article was written to discuss digestible energy of forages and their importance. Is it typical to rate a forage’s nutritive value based on its crude protein content? A forage with crude protein of less than 9 percent will possibly meet the protein needs of dry, non-pregnant cows, but there is a...

  11. Severe childhood asthma and allergy to furry animals: refined assessment using molecular-based allergy diagnostics.

    Science.gov (United States)

    Konradsen, Jon R; Nordlund, Björn; Onell, Annica; Borres, Magnus P; Grönlund, Hans; Hedlin, Gunilla

    2014-03-01

    Allergy to cats and dogs and polysensitization towards these animals are associated with severe childhood asthma. Molecular-based allergy diagnostics offers new opportunities for improved characterization and has been suggested to be particularly useful in patients with polysensitization and/or severe asthma. The aim was to use extract- and molecular-based allergy diagnostics to compare patterns of IgE sensitization towards aeroallergens in children with problematic severe and controlled asthma. Children with a positive ImmunoCAP towards any furry animal (cat, dog or horse) were recruited from a Nationwide Swedish study on severe childhood asthma. Severe (n = 37, age 13 years) and controlled (n = 28, age 14 years) asthmatics underwent assessment of allergic sensitization by ImmunoCap (kUA /l) and immunosolid-phase allergen chip (ISAC). In addition, Asthma Control Test, spirometry and a methacholine challenge were performed. Children with severe asthma had lower asthma control (p Molecular-based allergy diagnostics revealed a more complex molecular spreading of allergen components in children with the most severe disease. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  12. Rumen passage kinetics of forage and concentrate derived fiber in dairy cows

    DEFF Research Database (Denmark)

    Krämer, Monika; Lund, Peter; Weisbjerg, Martin Riis

    2013-01-01

    , were used in a completely randomized block experiment. Treatments differed in forage type (corn silage versus grass silage) and forage:concentrate ratio (50:50 versus 75:25 on organic matter basis). Fiber passage kinetics were studied based on rumen evacuations and on marker excretion profiles in feces...... Cr-EDTA single pulse dosed into the rumen, followed by sampling of rumen liquid from both, the ventral and medial rumen. Rumen mean retention time did not differ between forages when based on Yb-excretion profiles but was numerically longer for grass silage than corn silage based rations using rumen....... The forage type itself (corn silage and grass silage) rather than ration composition seemed to determine the total tract retention time of forage fiber...

  13. Pig Feeding under the Potato-green Forage Base System with or without Addition of Herbs versus a Concentrate Based System: Effect on Post-slaughter Performance and Pork Characteristics

    Directory of Open Access Journals (Sweden)

    Zofia Turyk

    2014-05-01

    Full Text Available This study examined carcass and meat quality parameters in growing/finishing pigs fed unconventionally versus the concentrate-based system. Ninety-six, 12 wk old pigs (34±SD 0.3 kg were randomly divided into three groups, assigned to one of the three dietary treatments: standard complete concentrate mixture, conventional (C diet; unconventional, steamed potato-green forage-concentrate based diet (U diet, and unconventional basal diet+herbage mix (UH diet. Pigs fed U diet showed lower dressing percentage, meatiness, loin eye area, and weight of pork neck (p≤0.05, but their carcasses were significantly (p≤0.05 longer and had increased backfat depth (p≤0.05. There was no impact of the diet on the meat content of dry matter, crude ash, acidity, and colour parameters of m. longissimus. Unconventional feeding significantly (p≤0.05 elevated water the holding capacity of m. longissimus and slightly improved the sensory attributes analysis of meat. The addition of herbs resulted in increased loin eye area (p≤0.05, decreased fat content (p≤0.05 in m. longissimus, and tended to improve some sensory attributes of meat. There were significant gender differences in response to all diets. There were significant diet×sex interactions for some measured variables, but there were no clearly identifiable trends with regard to any specific carcass or meat parameters. Feeding unconventional diet to pigs may offer better culinary attributes of the meat, and improve some technologically important characteristics of pig carcass, but may negatively affect some carcass or meat parameters.

  14. Taxonomic characterization of honey bee (Apis mellifera) pollen foraging based on non-overlapping paired-end sequencing of nuclear ribosomal loci

    Science.gov (United States)

    Cornman, Robert S.; Otto, Clint R.; Iwanowicz, Deborah; Pettis, Jeffery S

    2015-01-01

    Identifying plant taxa that honey bees (Apis mellifera) forage upon is of great apicultural interest, but traditional methods are labor intensive and may lack resolution. Here we evaluate a high-throughput genetic barcoding approach to characterize trap-collected pollen from multiple North Dakota apiaries across multiple years. We used the Illumina MiSeq platform to generate sequence scaffolds from non-overlapping 300-bp paired-end sequencing reads of the ribosomal internal transcribed spacers (ITS). Full-length sequence scaffolds represented ~530 bp of ITS sequence after adapter trimming, drawn from the 5’ of ITS1 and the 3’ of ITS2, while skipping the uninformative 5.8S region. Operational taxonomic units (OTUs) were picked from scaffolds clustered at 97% identity, searched by BLAST against the nt database, and given taxonomic assignments using the paired-read lowest common ancestor approach. Taxonomic assignments and quantitative patterns were consistent with known plant distributions, phenology, and observational reports of pollen foraging, but revealed an unexpected contribution from non-crop graminoids and wetland plants. The mean number of plant species assignments per sample was 23.0 (+/- 5.5) and the mean species diversity (effective number of equally abundant species) was 3.3 (+/- 1.2). Bray-Curtis similarities showed good agreement among samples from the same apiary and sampling date. Rarefaction plots indicated that fewer than 50,000 reads are typically needed to characterize pollen samples of this complexity. Our results show that a pre-compiled, curated reference database is not essential for genus-level assignments, but species-level assignments are hindered by database gaps, reference length variation, and probable errors in the taxonomic assignment, requiring post-hoc evaluation. Although the effective per-sample yield achieved using custom MiSeq amplicon primers was less than the machine maximum, primarily due to lower “read2” quality

  15. Gene-based vaccine development for improving animal production in developing countries. Possibilities and constraints

    International Nuclear Information System (INIS)

    Egerton, J.R.

    2005-01-01

    For vaccine production, recombinant antigens must be protective. Identifying protective antigens or candidate antigens is an essential precursor to vaccine development. Even when a protective antigen has been identified, cloning of its gene does not lead directly to vaccine development. The fimbrial protein of Dichelobacter nodosus, the agent of foot-rot in ruminants, was known to be protective. Recombinant vaccines against this infection are ineffective if expressed protein subunits are not assembled as mature fimbriae. Antigenic competition between different, but closely related, recombinant antigens limited the use of multivalent vaccines based on this technology. Recombinant antigens may need adjuvants to enhance response. DNA vaccines, potentiated with genes for different cytokines, may replace the need for aggressive adjuvants, and especially where cellular immunity is essential for protection. The expression of antigens from animal pathogens in plants and the demonstration of some immunity to a disease like rinderpest after ingestion of these, suggests an alternative approach to vaccination by injection. Research on disease pathogenesis and the identification of candidate antigens is specific to the disease agent. The definition of expression systems and the formulation of a vaccine for each disease must be followed by research to establish safety and efficacy. Where vaccines are based on unique gene sequences, the intellectual property is likely to be protected by patent. Organizations, licensed to produce recombinant vaccines, expect to recover their costs and to make a profit. The consequence is that genetically-derived vaccines are expensive. The capacity of vaccines to help animal owners of poorer countries depends not only on quality and cost but also on the veterinary infrastructure where they are used. Ensuring the existence of an effective animal health infrastructure in developing countries is as great a challenge for the developed world as

  16. Animal-Based Measures to Assess the Welfare of Extensively Managed Ewes

    Science.gov (United States)

    Hemsworth, Paul; Doyle, Rebecca

    2017-01-01

    Simple Summary The aim of this study was to assess the reliability and practicality of 10 animal-based welfare measures for extensively managed ewes, which were derived from the scientific literature, previous welfare protocols and through consultation with veterinarians and animal welfare scientists. Measures were examined on 100 Merino ewes, which were individually identified and repeatedly examined at mid-pregnancy, mid-lactation and weaning. Body condition score, fleece condition, skin lesions, tail length, dag score and lameness are proposed for on-farm use in welfare assessments of extensive sheep production systems. These six welfare measures, which address the main welfare concerns for extensively managed ewes, can be reliably and feasibly measured in the field. Abstract The reliability and feasibility of 10 animal-based measures of ewe welfare were examined for use in extensive sheep production systems. Measures were: Body condition score (BCS), rumen fill, fleece cleanliness, fleece condition, skin lesions, tail length, dag score, foot-wall integrity, hoof overgrowth and lameness, and all were examined on 100 Merino ewes (aged 2–4 years) during mid-pregnancy, mid-lactation and weaning by a pool of nine trained observers. The measures of BCS, fleece condition, skin lesions, tail length, dag score and lameness were deemed to be reliable and feasible. All had good observer agreement, as determined by the percentage of agreement, Kendall’s coefficient of concordance (W) and Kappa (k) values. When combined, these nutritional and health measures provide a snapshot of the current welfare status of ewes, as well as evidencing previous or potential welfare issues. PMID:29295551

  17. Foraging fidelity as a recipe for a long life: foraging strategy and longevity in male Southern Elephant Seals.

    Directory of Open Access Journals (Sweden)

    Matthieu Authier

    Full Text Available Identifying individual factors affecting life-span has long been of interest for biologists and demographers: how do some individuals manage to dodge the forces of mortality when the vast majority does not? Answering this question is not straightforward, partly because of the arduous task of accurately estimating longevity in wild animals, and of the statistical difficulties in correlating time-varying ecological covariables with a single number (time-to-event. Here we investigated the relationship between foraging strategy and life-span in an elusive and large marine predator: the Southern Elephant Seal (Mirounga leonina. Using teeth recovered from dead males on îles Kerguelen, Southern Ocean, we first aged specimens. Then we used stable isotopic measurements of carbon (δ13C in dentin to study the effect of foraging location on individual life-span. Using a joint change-point/survival modelling approach which enabled us to describe the ontogenetic trajectory of foraging, we unveiled how a stable foraging strategy developed early in life positively covaried with longevity in male Southern Elephant Seals. Coupled with an appropriate statistical analysis, stable isotopes have the potential to tackle ecological questions of long standing interest but whose answer has been hampered by logistic constraints.

  18. Forage use to improve environmental sustainability of ruminant production.

    Science.gov (United States)

    Guyader, J; Janzen, H H; Kroebel, R; Beauchemin, K A

    2016-08-01

    Ruminants raised for meat and milk are important sources of protein in human diets worldwide. Their unique digestive system allows them to derive energy and nourishment from forages, making use of vast areas of grazing lands not suitable for arable cropping or biofuel production and avoiding direct competition for grain that can be used as human food. However, sustaining an ever-growing population of ruminants consuming forages poses a dilemma: while exploiting their ecological niche, forage-fed ruminants produce large amount of enteric methane, a potent greenhouse gas. Resolving this quandary would allow ruminants an expanded role in meeting growing global demands for livestock products. One way around the dilemma is to devise forage-based diets and feeding systems that reduce methane emissions per unit of milk or meat produced. Ongoing research has made significant strides toward this objective. A wider opportunity is to look beyond methane emissions alone and consider all greenhouse gas emissions from the entire livestock-producing system. For example, by raising ruminants in systems using forages, some of the methane emissions can be offset by preserving or enhancing soil carbon reserves, thereby withholding carbon dioxide from the air. Similarly, well-managed systems based on forages may reduce synthetic fertilizer use by more effective use of manure and nitrogen-fixing plants, thereby curtailing nitrous oxide emissions. The potential environmental benefits of forage-based systems may be expanded even further by considering their other ecological benefits, such as conserving biodiversity, improving soil health, enhancing water quality, and providing wildlife habitat. The quandary, then, can be alleviated by managing ruminants within a holistic land-livestock synchrony that considers not only methane emissions but also suppression of other greenhouse gases as well as other ecological benefits. Given the complexity of such systems, there likely are no singular

  19. Development of Web-based Distributed Cooperative Development Environmentof Sign-Language Animation System and its Evaluation

    Science.gov (United States)

    Yuizono, Takaya; Hara, Kousuke; Nakayama, Shigeru

    A web-based distributed cooperative development environment of sign-language animation system has been developed. We have extended the system from the previous animation system that was constructed as three tiered system which consists of sign-language animation interface layer, sign-language data processing layer, and sign-language animation database. Two components of a web client using VRML plug-in and web servlet are added to the previous system. The systems can support humanoid-model avatar for interoperability, and can use the stored sign language animation data shared on the database. It is noted in the evaluation of this system that the inverse kinematics function of web client improves the sign-language animation making.

  20. Kinetic parametric estimation in animal PET molecular imaging based on artificial immune network

    International Nuclear Information System (INIS)

    Chen Yuting; Ding Hong; Lu Rui; Huang Hongbo; Liu Li

    2011-01-01

    Objective: To develop an accurate,reliable method without the need of initialization in animal PET modeling for estimation of the tracer kinetic parameters based on the artificial immune network. Methods: The hepatic and left ventricular time activity curves (TACs) were obtained by drawing ROIs of liver tissue and left ventricle on dynamic 18 F-FDG PET imaging of small mice. Meanwhile, the blood TAC was analyzed by sampling the tail vein blood at different time points after injection. The artificial immune network for parametric optimization of pharmacokinetics (PKAIN) was adapted to estimate the model parameters and the metabolic rate of glucose (K i ) was calculated. Results: TACs of liver,left ventricle and tail vein blood were obtained.Based on the artificial immune network, K i in 3 mice was estimated as 0.0024, 0.0417 and 0.0047, respectively. The average weighted residual sum of squares of the output model generated by PKAIN was less than 0.0745 with a maximum standard deviation of 0.0084, which indicated that the proposed PKAIN method can provide accurate and reliable parametric estimation. Conclusion: The PKAIN method could provide accurate and reliable tracer kinetic modeling in animal PET imaging without the need of initialization of model parameters. (authors)

  1. Analyzer-based imaging of spinal fusion in an animal model

    International Nuclear Information System (INIS)

    Kelly, M E; Beavis, R C; Allen, L A; Fiorella, David; Schueltke, E; Juurlink, B H; Chapman, L D; Zhong, Z

    2008-01-01

    Analyzer-based imaging (ABI) utilizes synchrotron radiation sources to create collimated monochromatic x-rays. In addition to x-ray absorption, this technique uses refraction and scatter rejection to create images. ABI provides dramatically improved contrast over standard imaging techniques. Twenty-one adult male Wistar rats were divided into four experimental groups to undergo the following interventions: (1) non-injured control, (2) decortication alone, (3) decortication with iliac crest bone grafting and (4) decortication with iliac crest bone grafting and interspinous wiring. Surgical procedures were performed at the L5-6 level. Animals were killed at 2, 4 and 6 weeks after the intervention and the spine muscle blocks were excised. Specimens were assessed for the presence of fusion by (1) manual testing, (2) conventional absorption radiography and (3) ABI. ABI showed no evidence of bone fusion in groups 1 and 2 and showed solid or possibly solid fusion in subjects from groups 3 and 4 at 6 weeks. Metal artifacts were not present in any of the ABI images. Conventional absorption radiographs did not provide diagnostic quality imaging of either the graft material or fusion masses in any of the specimens in any of the groups. Synchrotron-based ABI represents a novel imaging technique which can be used to assess spinal fusion in a small animal model. ABI produces superior image quality when compared to conventional radiographs

  2. Functional identity and diversity of animals predict ecosystem functioning better than species-based indices.

    Science.gov (United States)

    Gagic, Vesna; Bartomeus, Ignasi; Jonsson, Tomas; Taylor, Astrid; Winqvist, Camilla; Fischer, Christina; Slade, Eleanor M; Steffan-Dewenter, Ingolf; Emmerson, Mark; Potts, Simon G; Tscharntke, Teja; Weisser, Wolfgang; Bommarco, Riccardo

    2015-02-22

    Drastic biodiversity declines have raised concerns about the deterioration of ecosystem functions and have motivated much recent research on the relationship between species diversity and ecosystem functioning. A functional trait framework has been proposed to improve the mechanistic understanding of this relationship, but this has rarely been tested for organisms other than plants. We analysed eight datasets, including five animal groups, to examine how well a trait-based approach, compared with a more traditional taxonomic approach, predicts seven ecosystem functions below- and above-ground. Trait-based indices consistently provided greater explanatory power than species richness or abundance. The frequency distributions of single or multiple traits in the community were the best predictors of ecosystem functioning. This implies that the ecosystem functions we investigated were underpinned by the combination of trait identities (i.e. single-trait indices) and trait complementarity (i.e. multi-trait indices) in the communities. Our study provides new insights into the general mechanisms that link biodiversity to ecosystem functioning in natural animal communities and suggests that the observed responses were due to the identity and dominance patterns of the trait composition rather than the number or abundance of species per se. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  3. Multimodal floral signals and moth foraging decisions.

    Directory of Open Access Journals (Sweden)

    Jeffrey A Riffell

    Full Text Available Combinations of floral traits - which operate as attractive signals to pollinators - act on multiple sensory modalities. For Manduca sexta hawkmoths, how learning modifies foraging decisions in response to those traits remains untested, and the contribution of visual and olfactory floral displays on behavior remains unclear.Using M. sexta and the floral traits of two important nectar resources in southwestern USA, Datura wrightii and Agave palmeri, we examined the relative importance of olfactory and visual signals. Natural visual and olfactory cues from D. wrightii and A. palmeri flowers permits testing the cues at their native intensities and composition - a contrast to many studies that have used artificial stimuli (essential oils, single odorants that are less ecologically relevant. Results from a series of two-choice assays where the olfactory and visual floral displays were manipulated showed that naïve hawkmoths preferred flowers displaying both olfactory and visual cues. Furthermore, experiments using A. palmeri flowers - a species that is not very attractive to hawkmoths - showed that the visual and olfactory displays did not have synergistic effects. The combination of olfactory and visual display of D. wrightii, however - a flower that is highly attractive to naïve hawkmoths - did influence the time moths spent feeding from the flowers. The importance of the olfactory and visual signals were further demonstrated in learning experiments in which experienced moths, when exposed to uncoupled floral displays, ultimately chose flowers based on the previously experienced olfactory, and not visual, signals. These moths, however, had significantly longer decision times than moths exposed to coupled floral displays.These results highlight the importance of specific sensory modalities for foraging hawkmoths while also suggesting that they learn the floral displays as combinatorial signals and use the integrated floral traits from their memory

  4. Multimodal Floral Signals and Moth Foraging Decisions

    Science.gov (United States)

    Riffell, Jeffrey A.; Alarcón, Ruben

    2013-01-01

    Background Combinations of floral traits – which operate as attractive signals to pollinators – act on multiple sensory modalities. For Manduca sexta hawkmoths, how learning modifies foraging decisions in response to those traits remains untested, and the contribution of visual and olfactory floral displays on behavior remains unclear. Methodology/Principal Findings Using M. sexta and the floral traits of two important nectar resources in southwestern USA, Datura wrightii and Agave palmeri, we examined the relative importance of olfactory and visual signals. Natural visual and olfactory cues from D. wrightii and A. palmeri flowers permits testing the cues at their native intensities and composition – a contrast to many studies that have used artificial stimuli (essential oils, single odorants) that are less ecologically relevant. Results from a series of two-choice assays where the olfactory and visual floral displays were manipulated showed that naïve hawkmoths preferred flowers displaying both olfactory and visual cues. Furthermore, experiments using A. palmeri flowers – a species that is not very attractive to hawkmoths – showed that the visual and olfactory displays did not have synergistic effects. The combination of olfactory and visual display of D. wrightii, however – a flower that is highly attractive to naïve hawkmoths – did influence the time moths spent feeding from the flowers. The importance of the olfactory and visual signals were further demonstrated in learning experiments in which experienced moths, when exposed to uncoupled floral displays, ultimately chose flowers based on the previously experienced olfactory, and not visual, signals. These moths, however, had significantly longer decision times than moths exposed to coupled floral displays. Conclusions/Significance These results highlight the importance of specific sensory modalities for foraging hawkmoths while also suggesting that they learn the floral displays as

  5. Colorado animal-based plague surveillance systems: relationships between targeted animal species and prediction efficacy of areas at risk for humans.

    Science.gov (United States)

    Lowell, Jennifer L; Eisen, Rebecca J; Schotthoefer, Anna M; Xiaocheng, Liang; Montenieri, John A; Tanda, Dale; Pape, John; Schriefer, Martin E; Antolin, Michael F; Gage, Kenneth L

    2009-06-01

    Human plague risks (Yersinia pestis infection) are greatest when epizootics cause high mortality among this bacterium's natural rodent hosts. Therefore, health departments in plague-endemic areas commonly establish animal-based surveillance programs to monitor Y. pestis infection among plague hosts and vectors. The primary objectives of our study were to determine whether passive animal-based plague surveillance samples collected in Colorado from 1991 to 2005 were sampled from high human plague risk areas and whether these samples provided information useful for predicting human plague case locations. By comparing locations of plague-positive animal samples with a previously constructed GIS-based plague risk model, we determined that the majority of plague-positive Gunnison's prairie dogs (100%) and non-prairie dog sciurids (85.82%), and moderately high percentages of sigmodontine rodents (71.4%), domestic cats (69.3%), coyotes (62.9%), and domestic dogs (62.5%) were recovered within 1 km of the nearest area posing high peridomestic risk to humans. In contrast, the majority of white-tailed prairie dog (66.7%), leporid (cottontailed and jack rabbits) (71.4%), and black-tailed prairie dog (93.0%) samples originated more than 1 km from the nearest human risk habitat. Plague-positive animals or their fleas were rarely (one of 19 cases) collected within 2 km of a case exposure site during the 24 months preceding the dates of illness onset for these cases. Low spatial accuracy for identifying epizootic activity prior to human plague cases suggested that other mammalian species or their fleas are likely more important sources of human infection in high plague risk areas. To address this issue, epidemiological observations and multi-locus variable number tandem repeat analyses (MLVA) were used to preliminarily identify chipmunks as an under-sampled, but potentially important, species for human plague risk in Colorado.

  6. Forage and rangeland plants from uranium mine soils: long-term hazard to herbivores and livestock?

    Science.gov (United States)

    Gramss, Gerhard; Voigt, Klaus-Dieter

    2014-06-01

    Metalliferous uranium mine overburden soils integrated into arable land or stabilized by perennial rangeland plants evoke concern about the quality of crops and the exposure of grazing and thereby soil-ingesting (wildlife) herbivores to heavy metals (HM) and radionuclides. In a 2-year trial, thirteen annual and perennial forage and rangeland plants were thus potted on, or taken from, cultivated field soil of a metalliferous hot spot near Ronneburg (Germany). The content of soil and shoot tissues in 20 minerals was determined by ICP-MS to estimate HM (and uranium) toxicities to grazing animals and the plants themselves, and to calculate the long-term persistence of the metal toxicants (soil clean-up times) from the annual uptake rates of the plants. On Ronneburg soil elevated in As, Cd, Cu, Mn, Pb, U, and Zn, the shoot mineral content of all test plants remained preferentially in the range of "normal plant concentrations" but reached up to the fourfold to sixfold in Mn, Ni, and Zn, the 1.45- to 21.5-fold of the forage legislative limit in Cd, and the 10- to 180-fold of common herb concentrations in U. Shoot and the calculated root concentrations in Cd, Cu, Ni, and Zn accounted for phytotoxic effects at least to grasses and cereals. Based on WHO PTWI values for the tolerable weekly human Cd and Pb intake, the expanded Cd and Pb limits for forage, and reported rates of hay, roots, and adhering-soil ingestion, the tolerable daily intake rates of 0.65/11.6 mg in Cd/Pb by a 65 kg herbivore would be surpassed by the 11- to 27/0.7- to 4.7-fold across the year, with drastic consequences for winter-grazing and thereby high rates of roots and soil-ingesting animals. The daily intake of 5.3-31.5 mg of the alpha radiation emitter, U, may be less disastrous to short-lived herbivores. The annual phytoextraction rates of critical HM by the tested excluder crops indicate that hundreds to thousands of years are necessary to halve the HM and (long-lived) radionuclide load of

  7. Trait-mediated trophic interactions: is foraging theory keeping up?

    Science.gov (United States)

    Railsback, Steven F; Harvey, Bret C

    2013-02-01

    Many ecologists believe that there is a lack of foraging theory that works in community contexts, for populations of unique individuals each making trade-offs between food and risk that are subject to feedbacks from behavior of others. Such theory is necessary to reproduce the trait-mediated trophic interactions now recognized as widespread and strong. Game theory can address feedbacks but does not provide foraging theory for unique individuals in variable environments. 'State- and prediction-based theory' (SPT) is a new approach that combines existing trade-off methods with routine updating: individuals regularly predict future food availability and risk from current conditions to optimize a fitness measure. SPT can reproduce a variety of realistic foraging behaviors and trait-mediated trophic interactions with feedbacks, even when the environment is unpredictable. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Attraction of Vespula germanica (Hymenoptera: Vespidae) foragers by conspecific heads.

    Science.gov (United States)

    d'Adamo, P; Corley, J C; Lozada, M

    2001-08-01

    The socialwasp Vespula germanica (F.) is a serious pest in many regions it has invaded. Control programs to reduce its populations are commonly based on the use of poison baits. These baits also attract nonpestiferous invertebrates and vertebrates. In this work we studied the attraction of V. germanica foragers by conspecific worker squashes, comparing the effect of head and abdomen squashes in wasps behavior. We found that head squashes attract V. germanica foragers, elicit landing and transportation to nests. Furthermore, the addition of squashed heads to a protein bait increased attraction. This could be an alternative to improve baiting programs.

  9. The effects of spatially heterogeneous prey distributions on detection patterns in foraging seabirds.

    Directory of Open Access Journals (Sweden)

    Octavio Miramontes

    Full Text Available Many attempts to relate animal foraging patterns to landscape heterogeneity are focused on the analysis of foragers movements. Resource detection patterns in space and time are not commonly studied, yet they are tightly coupled to landscape properties and add relevant information on foraging behavior. By exploring simple foraging models in unpredictable environments we show that the distribution of intervals between detected prey (detection statistics is mostly determined by the spatial structure of the prey field and essentially distinct from predator displacement statistics. Detections are expected to be Poissonian in uniform random environments for markedly different foraging movements (e.g. Lévy and ballistic. This prediction is supported by data on the time intervals between diving events on short-range foraging seabirds such as the thick-billed murre (Uria lomvia. However, Poissonian detection statistics is not observed in long-range seabirds such as the wandering albatross (Diomedea exulans due to the fractal nature of the prey field, covering a wide range of spatial scales. For this scenario, models of fractal prey fields induce non-Poissonian patterns of detection in good agreement with two albatross data sets. We find that the specific shape of the distribution of time intervals between prey detection is mainly driven by meso and submeso-scale landscape structures and depends little on the forager strategy or behavioral responses.

  10. Magnetite-based Magnetoreception in Animals: 25+ Years of Theory & Experimentation

    Science.gov (United States)

    Kirschvink, J. L.; Walker, M. M.

    2005-12-01

    Living organisms ranging from bacteria through higher vertebrates rely on orientation, navigation, and homing to survive. Any sensory cue that enhances these behaviors will be subject to intense natural selection over geological time. Reproducible behavioral responses to earth-strength magnetic fields(1) have been documented in Bacteria, Protoctists, and in nearly every major group of animals, and are possibly also present in the Archaea. Several groups of animals, including birds and cetaceans, respond behaviorally to magnetic anomalies below 100 nT in magnitude, implying that their magnetoreception ability approaches the thermal noise limit. This approach to thermal noise is commonly observed in other sensory systems, including hearing, olfaction, and electroreception. The hypothesis of magnetite-based magnetoreception(2) is the only theory proposed so far that is capable of explaining all of the magnetic behavioral data. Tiny crystals of single-domain magnetite (or in some bacteria, greigite) rotate the cells of microorganisms passively like a simple compass needle. The initial detection of biogenic magnetite with rock magnetic techniques in birds and bees over 25 years ago has led progressively to the identification of a group of specialized cells in fish and birds which contain organized magnetite-containing structures. In these animals (and presumably all vertebrates) magnetic signals are transmitted to the brain via the ophthalmic branch of the trigeminal nerve(3, 4). Experiments with pulse-remagnetization, like those that convert North-seeking bacteria into South-seekers, have dramatic effects on animal behavior, confirming the role of magnetite in the sensory system. This is therefore a general mechanism for a highly sensitive magnetic sense, the origin of which probably dates to the ancestral metazoan, and perhaps earlier. The largest debate presently occurring in the field concerns the interpretation of magnetic compass responses that vary with intensity

  11. Therapeutic evaluation of grain based functional food formulation in a geriatric animal model.

    Science.gov (United States)

    Teradal, Deepa; Joshi, Neena; Aladakatti, Ravindranath H

    2017-08-01

    This study investigates the effect of wholesome grain based functional food formulation, on clinical and biochemical parameters in 24-30 months old Wistar albino geriatric rats, corresponding to human age 60-75 years. Animals were randomly divided into five, groups. Experimental diets were compared to the basal rat diet (Group I). Four food, formulation were-wheat based (Group II), finger millet based (Group III), wheat based, diet + fenugreek seed powder (Group IV), finger millet based diet + fenugreek powder, (Group V). These five types of diets were fed to the experimental rats for 6 weeks. Hematological and biochemical parameters were evaluated. The results showed that, feed intake was influenced by the type of feed. Diets supplemented with, fenugreek (Group IV) caused a significant increase in serum hemoglobin. The total serum protein values were significantly highest in Group III. Total serum albumin was found to be lower in Group I and highest in Group II. The concentration of BUN was highest in Group I and the lowest in control diet. Serum cholesterol and glucose were significantly reduced in Group IV. Several hematological and serum mineral values were influenced by the type of diet. The type of diet did not influence the organs weight. A moderate hypoglycemic and hypercholesterolemic effect was observed in composite mix fed rats. This study clearly justifies the recommendation to use wholesome grain based functional foods for geriatric population.

  12. Temporal fractals in seabird foraging behaviour: diving through the scales of time

    Science.gov (United States)

    Macintosh, Andrew J. J.; Pelletier, Laure; Chiaradia, Andre; Kato, Akiko; Ropert-Coudert, Yan

    2013-05-01

    Animal behaviour exhibits fractal structure in space and time. Fractal properties in animal space-use have been explored extensively under the Lévy flight foraging hypothesis, but studies of behaviour change itself through time are rarer, have typically used shorter sequences generated in the laboratory, and generally lack critical assessment of their results. We thus performed an in-depth analysis of fractal time in binary dive sequences collected via bio-logging from free-ranging little penguins (Eudyptula minor) across full-day foraging trips (216 data points; 4 orders of temporal magnitude). Results from 4 fractal methods show that dive sequences are long-range dependent and persistent across ca. 2 orders of magnitude. This fractal structure correlated with trip length and time spent underwater, but individual traits had little effect. Fractal time is a fundamental characteristic of penguin foraging behaviour, and its investigation is thus a promising avenue for research on interactions between animals and their environments.

  13. Echolocating bats use future-target information for optimal foraging.

    Science.gov (United States)

    Fujioka, Emyo; Aihara, Ikkyu; Sumiya, Miwa; Aihara, Kazuyuki; Hiryu, Shizuko

    2016-04-26

    When seeing or listening to an object, we aim our attention toward it. While capturing prey, many animal species focus their visual or acoustic attention toward the prey. However, for multiple prey items, the direction and timing of attention for effective foraging remain unknown. In this study, we adopted both experimental and mathematical methodology with microphone-array measurements and mathematical modeling analysis to quantify the attention of echolocating bats that were repeatedly capturing airborne insects in the field. Here we show that bats select rational flight paths to consecutively capture multiple prey items. Microphone-array measurements showed that bats direct their sonar attention not only to the immediate prey but also to the next prey. In addition, we found that a bat's attention in terms of its flight also aims toward the next prey even when approaching the immediate prey. Numerical simulations revealed a possibility that bats shift their flight attention to control suitable flight paths for consecutive capture. When a bat only aims its flight attention toward its immediate prey, it rarely succeeds in capturing the next prey. These findings indicate that bats gain increased benefit by distributing their attention among multiple targets and planning the future flight path based on additional information of the next prey. These experimental and mathematical studies allowed us to observe the process of decision making by bats during their natural flight dynamics.

  14. Predicting foraging hotspots for Yelkouan Shearwater in the Black Sea

    Science.gov (United States)

    Pérez-Ortega, María; İsfendiyaroğlu, Süreyya

    2017-07-01

    The Yelkouan shearwater (Puffinus yelkouan) is a vulnerable species endemic to the Mediterranean Region, but there is little information of its ecology particularly when at sea. In this study, we assessed the habitat use by Yelkouan shearwater in the Black Sea during the breeding (March-July) and non-breeding (August-February) periods of 2013, using boat-based surveys and shore-based counts. We created a species distribution model (SDM) based on the environmental variables that most accurately reflected the oceanographic habitat of this species in order to delineate foraging hotspots. Our habitat modelling analyses suggest that Yelkouan shearwaters respond to complex bio-physical coupling, as evidenced by their association with oceanographic variables. Foraging Yelkouan shearwaters mainly occurred on the western Black Sea continental shelf, indicating that Yelkouan shearwaters were foraging in shallow, cold and coastal waters. In the non-breeding period, Yelkouan Shearwater occurred beyond the Black Sea continental shelf, a wide pelagic extension of sea, indicating that shearwaters foraged in deep, warm and pelagic waters. These results are consistent with earlier studies, which identified the Black Sea as an important congregation site for Mediterranean Yelkouan shearwater populations outside the breeding season. This study demonstrates how the integration of boat-based survey data, shore-based counts and modelling can provide a wider understanding of the linkage between marine ecosystems that is mediated by marine megafauna such as pelagic seabirds.

  15. Latitudinal range influences the seasonal variation in the foraging behavior of marine top predators.

    Directory of Open Access Journals (Sweden)

    Stella Villegas-Amtmann

    Full Text Available Non-migratory resident species should be capable of modifying their foraging behavior to accommodate changes in prey abundance and availability associated with a changing environment. Populations that are better adapted to change will have higher foraging success and greater potential for survival in the face of climate change. We studied two species of resident central place foragers from temperate and equatorial regions with differing population trends and prey availability associated to season, the California sea lion (Zalophus californianus (CSL whose population is increasing and the endangered Galapagos sea lion (Zalophus wollebaeki (GSL whose population is declining. To determine their response to environmental change, we studied and compared their diving behavior using time-depth recorders and satellite location tags and their diet by measuring C and N isotope ratios during a warm and a cold season. Based on latitudinal differences in oceanographic productivity, we hypothesized that the seasonal variation in foraging behavior would differ for these two species. CSL exhibited greater seasonal variability in their foraging behavior as seen in changes to their diving behavior, foraging areas and diet between seasons. Conversely, GSL did not change their diving behavior between seasons, presenting three foraging strategies (shallow, deep and bottom divers during both. GSL exhibited greater dive and foraging effort than CSL. We suggest that during the warm and less productive season a greater range of foraging behaviors in CSL was associated with greater competition for prey, which relaxed during the cold season when resource availability was greater. GSL foraging specialization suggests that resources are limited throughout the year due to lower primary production and lower seasonal variation in productivity compared to CSL. These latitudinal differences influence their foraging success, pup survival and population growth reflected in

  16. Older and wiser? Age differences in foraging and learning by an endangered passerine.

    Science.gov (United States)

    Franks, Victoria R; Thorogood, Rose

    2018-03-01

    Birds use cues when foraging to help relocate food resources, but natural environments provide many potential cues and choosing which to use may depend on previous experience. Young animals have less experience of their environment compared to adults, so may be slower to learn cues or may need to sample the environment more. Whether age influences cue use and learning has, however, received little experimental testing in wild animals. Here we investigate effects of age in a wild population of hihi (Notiomystis cincta), a threatened New Zealand passerine. We manipulated bird feeders using a novel colour cue to indicate a food reward; once hihi learned its location, we rotated the feeder to determine whether the birds followed the colour or returned to the previous location. Both age groups made fewer errors over trials and learned the location of the food reward, but juveniles continued to sample unrewarding locations more than adults. Following a second rotation, more adults preferred to forage from the hole indicated by the colour cue than juveniles, despite this no longer being rewarding. Overall, juveniles spent longer in the feeder arena to reach the same proportion of foraging time as adults. Combined, these results suggest that juveniles and adults may use an "explore and exploit" foraging strategy differently, and this affects how efficiently they forage. Further work is needed to understand how juveniles may compensate for their inexperience in learning and foraging strategies. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

  17. Foraging under conditions of short-term exploitative competition: the case of stock traders

    Science.gov (United States)

    Saavedra, Serguei; Malmgren, R. Dean; Switanek, Nicholas; Uzzi, Brian

    2013-01-01

    Theory purports that animal foraging choices evolve to maximize returns, such as net energy intake. Empirical research in both human and non-human animals reveals that individuals often attend to the foraging choices of their competitors while making their own foraging choices. Owing to the complications of gathering field data or constructing experiments, however, broad facts relating theoretically optimal and empirically realized foraging choices are only now emerging. Here, we analyse foraging choices of a cohort of professional day traders who must choose between trading the same stock multiple times in a row—patch exploitation—or switching to a different stock—patch exploration—with potentially higher returns. We measure the difference between a trader's resource intake and the competitors' expected intake within a short period of time—a difference we call short-term comparative returns. We find that traders' choices can be explained by foraging heuristics that maximize their daily short-term comparative returns. However, we find no one-best relationship between different trading choices and net income intake. This suggests that traders' choices can be short-term win oriented and, paradoxically, maybe maladaptive for absolute market returns. PMID:23363635

  18. GRASS SPECIES FROM C-4 CARBON FIXATION GROUP: POLISH EXPERIMENT WITH A NOVEL ENERGY AND FORAGE PURPOSES CROP

    Directory of Open Access Journals (Sweden)

    Włodzimierz Majtkowski

    2010-02-01

    Full Text Available Experiment was conducted during four years 2003-2006. Materials used were three genus grass species of C-4 photosynthesis: Andropogon gerardi Vitman, Panicum virgatum L. and Miscanthus sacchariflorus (Maxim. Hack. Plants were planted at spring 1998. Agrotechnical part of experiment was conducted in Botanical Garden of Plant Breeding Acclimatization Institute in Bydgoszcz and analytical part in Department of Animal Nutrition and Feed Management, Faculty of Animal Breeding and Biology of University of Technology and Life Science in Bydgoszcz. Forage from grass C-4 photosynthesis were material of good ensilage suitability. High structural carbohydrates (NDF, ADF contents in tested forage dry matter suggest ensilage at early phases of plant development. Above results suggest to possibility of usage of forage from grass C-4 carbon fixation group for animal feeding purposes. C-4 grass forage should be recognized as a supplementary source of green matter in periods of insufficient access to traditional silage sources.

  19. How foraging works: uncertainty magnifies food-seeking motivation.

    Science.gov (United States)

    Anselme, Patrick; Güntürkün, Onur

    2018-03-08

    Food uncertainty has the effect of invigorating food-related responses. Psychologists have noted that mammals and birds respond more to a conditioned stimulus that unreliably predicts food delivery, and ecologists have shown that animals (especially small passerines) consume and/or hoard more food and can get fatter when access to that resource is unpredictable. Are these phenomena related? We think they are. Psychologists have proposed several mechanistic interpretations, while ecologists have suggested a functional interpretation: the effect of unpredictability on fat reserves and hoarding behavior is an evolutionary strategy acting against the risk of starvation when food is in short supply. Both perspectives are complementary, and we argue that the psychology of incentive motivational processes can shed some light on the causal mechanisms leading animals to seek and consume more food under uncertainty in the wild. Our theoretical approach is in agreement with neuroscientific data relating to the role of dopamine, a neurotransmitter strongly involved in incentive motivation, and its plausibility has received some explanatory and predictive value with respect to Pavlovian phenomena. Overall, we argue that the occasional and unavoidable absence of food rewards has motivational effects (called incentive hope) that facilitate foraging effort. It is shown that this hypothesis is computationally tenable, leading foragers in an unpredictable environment to consume more food items and to have higher long-term energy storage than foragers in a predictable environment.

  20. Agriscience Teachers' Implementation of Digital Game-based Learning in an Introductory Animal Science Course

    Science.gov (United States)

    Webb, Angela W.; Bunch, J. C.; Wallace, Maria F. G.

    2015-12-01

    In today's technological age, visions for technology integration in the classroom continue to be explored and examined. Digital game-based learning is one way to purposefully integrate technology while maintaining a focus on learning objectives. This case study sought to understand agriscience teachers' experiences implementing digital game-based learning in an introductory animal science course. From interviews with agriscience teachers on their experiences with the game, three themes emerged: (1) the constraints of inadequate and inappropriate technologies, and time to game implementation; (2) the shift in teacher and student roles necessitated by implementing the game; and (3) the inherent competitive nature of learning through the game. Based on these findings, we recommend that pre-service and in-service professional development opportunities be developed for teachers to learn how to implement digital game-based learning effectively. Additionally, with the potential for simulations that address cross-cutting concepts in the next generation science standards, digital game-based learning should be explored in various science teaching and learning contexts.

  1. Memory-Based Specification of Verbal Features for Classifying Animals into Super-Ordinate and Sub-Ordinate Categories

    OpenAIRE

    Takahiro Soshi; Norio Fujimaki; Atsushi Matsumoto; Aya S. Ihara

    2017-01-01

    Accumulating evidence suggests that category representations are based on features. Distinguishing features are considered to define categories, because of all-or-none responses for objects in different categories; however, it is unclear how distinguishing features actually classify objects at various category levels. The present study included 75 animals within three classes (mammal, bird, and fish), along with 195 verbal features. Healthy adults participated in memory-based feature-animal m...

  2. A clinical gamma camera-based pinhole collimated system for high resolution small animal SPECT imaging

    Energy Technology Data Exchange (ETDEWEB)

    Mejia, J.; Galvis-Alonso, O.Y., E-mail: mejia_famerp@yahoo.com.b [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Biologia Molecular; Castro, A.A. de; Simoes, M.V. [Faculdade de Medicina de Sao Jose do Rio Preto (FAMERP), SP (Brazil). Dept. de Clinica Medica; Leite, J.P. [Universidade de Sao Paulo (FMRP/USP), Ribeirao Preto, SP (Brazil). Fac. de Medicina. Dept. de Neurociencias e Ciencias do Comportamento; Braga, J. [Instituto Nacional de Pesquisas Espaciais (INPE), Sao Jose dos Campos, SP (Brazil). Div. de Astrofisica

    2010-11-15

    The main objective of the present study was to upgrade a clinical gamma camera to obtain high resolution tomographic images of small animal organs. The system is based on a clinical gamma camera to which we have adapted a special-purpose pinhole collimator and a device for positioning and rotating the target based on a computer-controlled step motor. We developed a software tool to reconstruct the target's three-dimensional distribution of emission from a set of planar projections, based on the maximum likelihood algorithm. We present details on the hardware and software implementation. We imaged phantoms and heart and kidneys of rats. When using pinhole collimators, the spatial resolution and sensitivity of the imaging system depend on parameters such as the detector-to-collimator and detector-to-target distances and pinhole diameter. In this study, we reached an object voxel size of 0.6 mm and spatial resolution better than 2.4 and 1.7 mm full width at half maximum when 1.5- and 1.0-mm diameter pinholes were used, respectively. Appropriate sensitivity to study the target of interest was attained in both cases. Additionally, we show that as few as 12 projections are sufficient to attain good quality reconstructions, a result that implies a significant reduction of acquisition time and opens the possibility for radiotracer dynamic studies. In conclusion, a high resolution single photon emission computed tomography (SPECT) system was developed using a commercial clinical gamma camera, allowing the acquisition of detailed volumetric images of small animal organs. This type of system has important implications for research areas such as Cardiology, Neurology or Oncology. (author)

  3. Interactive Multimedia-Based Animation: A Study of Effectiveness on Fashion Design Technology Learning

    Science.gov (United States)

    Wiana, W.

    2018-01-01

    The learning process is believed will reach optimal results if facilitated by diversity of learning’s device from aspects of the approach, method, media or it’s evaluation system, in individually, groups, or as well as classical. One of the learning’s Device can be developed in an attempt to improve the results of the study is Computer Based Learning (CBL). CBL was developed aim to help students to understand the concepts of the learning material which presented interactively by the system and able to provide information and learning process better. This research is closely related to efforts to improve the quality of Fashion design in digital format learning, with specific targets to generate interactive multimedia-based animation as effective media and learning resources for fashion design learning. Applications that are generated may be an option for delivering learning material as well as to engender interest in learning as well as understanding with students against the subject matter so that it can improve the learning achievements of students. The instruments used to collect data is a test sheet of mastering the concept which developed on the basis of indicators understanding the concept of fashion design, the material elements and principles of fashion design as well as application on making fashion design. As for the skills test is done through test performance to making fashion design in digital format. The results of testing against the mastery of concepts and skills of fashion designing in digital formatted shows that experimental group obtained significantly higher qualifications compared to the control group. That means that the use of interactive multimedia-based animation, effective to increased mastery of concepts and skills on making fashion design in digital format.

  4. PKU-PET-II: A novel SiPM-based PET imaging system for small animals

    Science.gov (United States)

    Xie, Zhaoheng; Li, Suying; Zhou, Kun; Vuletic, Ivan; Meng, Xiangxi; Zhu, Sihao; Xu, Huan; Yang, Kun; Xu, Baixuan; Zhang, Jinming; Ren, Qiushi

    2018-01-01

    The objective of this study was to introduce, describe, and validate the performance of a novel preclinical silicon photomultiplier (SiPM)-based PET system (PKU-PET-II). Briefly, the detector assembly consisted of cerium-doped lutetium-yttrium oxyorthosilicate (LYSO) crystals, with dimensions of 2 ×2 ×15 mm3, that offered a 60 mm transaxial field of view (FOV) and 32 mm axial FOV, respectively. The compact front-end electronics readout and digital controller implemented architecture in the FPGA were noteworthy improvements in PKU-PET-II over its predecessor (PKU-PET-I). Based on the National Electrical Manufacturers Association (NEMA) NU 04-2008 standards, the design of the PKU-PET-II system was validated by a phantom experiment. The results presented spatial resolution (evaluated as full width at half maximum) with a system range from 1.68 ±0.07 to 2.31 ±0.03 mm at the FOV center and from 1.43 ±0.02 to 2.10 ±0.10 mm at the 1/4th axial FOV, respectively. The system's absolute sensitivity at the center position was 1.35% with the coincidence window of 6 ns and energy window of 300-700 keV. In addition, the NEMA image quality phantom and an animal study results validated the system imaging performance in preclinical imaging application. In conclusion, this SiPM-based, small-animal PET system (PKU-PET-II) provided higher-resolution, adequate sensitivity, and excellent image quality and has potential as a useful tool for real-time imaging of disease progression and development in vivo.

  5. 3D animation of facial plastic surgery based on computer graphics

    Science.gov (United States)

    Zhang, Zonghua; Zhao, Yan

    2013-12-01

    More and more people, especial women, are getting desired to be more beautiful than ever. To some extent, it becomes true because the plastic surgery of face was capable in the early 20th and even earlier as doctors just dealing with war injures of face. However, the effect of post-operation is not always satisfying since no animation could be seen by the patients beforehand. In this paper, by combining plastic surgery of face and computer graphics, a novel method of simulated appearance of post-operation will be given to demonstrate the modified face from different viewpoints. The 3D human face data are obtained by using 3D fringe pattern imaging systems and CT imaging systems and then converted into STL (STereo Lithography) file format. STL file is made up of small 3D triangular primitives. The triangular mesh can be reconstructed by using hash function. Top triangular meshes in depth out of numbers of triangles must be picked up by ray-casting technique. Mesh deformation is based on the front triangular mesh in the process of simulation, which deforms interest area instead of control points. Experiments on face model show that the proposed 3D animation facial plastic surgery can effectively demonstrate the simulated appearance of post-operation.

  6. Effects of Using Graphics and Animation Online Problem-Based Learning on Visualization Skills among Students

    Science.gov (United States)

    Ariffin, A.; Samsudin, M. A.; Zain, A. N. Md.; Hamzah, N.; Ismail, M. E.

    2017-05-01

    The Engineering Drawing subject develops skills in geometry drawing becoming more professional. For the concept in Engineering Drawing, students need to have good visualization skills. Visualization is needed to help students get a start before translating into a drawing. So that, Problem Based Learning (PBL) using animation mode (PBL-A) and graphics mode (PBL-G) will be implemented in class. Problem-solving process is repeatedly able to help students interpret engineering drawings step work correctly and accurately. This study examined the effects of PBL-A online and PBL-G online on visualization skills of students in polytechnics. Sixty eight mechanical engineering students have been involved in this study. The visualization test adapted from Bennett, Seashore and Wesman was used in this study. Results showed significant differences in mean scores post-test of visualization skills among the students enrolled in PBL-G with the group of students who attended PBL-A online after effects of pre-test mean score is controlled. Therefore, the effects of animation modes have a positive impact on increasing students’ visualization skills.

  7. Starvation dynamics of a greedy forager

    Science.gov (United States)

    Bhat, U.; Redner, S.; Bénichou, O.

    2017-07-01

    We investigate the dynamics of a greedy forager that moves by random walking in an environment where each site initially contains one unit of food. Upon encountering a food-containing site, the forager eats all the food there and can subsequently hop an additional S steps without food before starving to death. Upon encountering an empty site, the forager goes hungry and comes one time unit closer to starvation. We investigate the new feature of forager greed; if the forager has a choice between hopping to an empty site or to a food-containing site in its nearest neighborhood, it hops preferentially towards food. If the neighboring sites all contain food or are all empty, the forager hops equiprobably to one of these neighbors. Paradoxically, the lifetime of the forager can depend non-monotonically on greed, and the sense of the non-monotonicity is opposite in one and two dimensions. Even more unexpectedly, the forager lifetime in one dimension is substantially enhanced when the greed is negative; here the forager tends to avoid food in its local neighborhood. We also determine the average amount of food consumed at the instant when the forager starves. We present analytic, heuristic, and numerical results to elucidate these intriguing phenomena.

  8. Valuation of pollinator forage services provided by Eucalyptus Cladocalyx

    CSIR Research Space (South Africa)

    De Lange, Willem J

    2013-08-01

    Full Text Available formed the basis for our calculations. The first scenario was an artificial diet as replacement for the forage provisioning service, which yielded a direct cost estimate of US$7.5m per year. The second was based on a Fynbos cultivation...

  9. Factors influencing forage preference of bushbuck and boer goats ...

    African Journals Online (AJOL)

    Reports on a study conducted to investigate whether bushbuck and boer goats, when given a choice of equally available plants, base their selection on a common set of criteria. Illustrates with tables and a graph. Keywords: Boer goats; Bushbuck; Capra hircus; Chemical analyses; Data analyses; Diet selection; Forages; ...

  10. Short Communication: Effect of forage sources and Saccharomyces ...

    African Journals Online (AJOL)

    Diets based on lucerne hay (462 g/kg DM) and maize silage (488 g/kg DM) were fed to determine the effects of 0 or 5 g SC 47 (8´109 cfu/g) on ruminal digestion, fermentation and protozoa population. Ruminal pH, acetate, propionate, degradation rate and effective degradability were significantly affected by the forage ...

  11. Attitudes toward the use of animals in chronic versus acute pain research: results of a web-based forum.

    Science.gov (United States)

    Ormandy, Elisabeth H; Griffin, Gilly

    2016-09-01

    When asked about the use of animals in biomedical research, people often state that the research is only acceptable if pain and distress are minimised. However, pain is caused when the aim is to study pain itself, resulting in unalleviated pain for many of the animals involved. Consequently, the use of animals in pain research is often considered contentious. To date, no research has explored people's views toward different types of animal-based pain research (e.g. chronic or acute pain). This study used a web-based survey to explore people's willingness to support the use of mice in chronic versus acute pain research. The majority of the participants opposed the use of mice for either chronic (68.3%) or acute (63.1%) pain research. There was no difference in the levels of support or opposition for chronic versus acute pain research. Unsupportive participants justified their opposition by focusing on the perceived lack of scientific merit, or the existence of non-animal alternatives. Supporters emphasised the potential benefits that could arise, with some stating that the benefits outweigh the costs. The majority of the participants were opposed to pain research involving mice, regardless of the nature and duration of the pain inflicted, or the perceived benefit of the research. A better understanding of public views toward animal use in pain research may provide a stronger foundation for the development of policy governing the use of animals in research where animals are likely to experience unalleviated pain. 2016 FRAME.

  12. Social familiarity modulates group living and foraging behaviour of juvenile predatory mites

    Science.gov (United States)

    Strodl, Markus A.; Schausberger, Peter

    2012-04-01

    Environmental stressors during early life may have persistent consequences for phenotypic development and fitness. In group-living species, an important stressor during juvenile development is the presence and familiarity status of conspecific individuals. To alleviate intraspecific conflicts during juvenile development, many animals evolved the ability to discriminate familiar and unfamiliar individuals based on prior association and use this ability to preferentially associate with familiar individuals. Assuming that familiar neighbours require less attention than unfamiliar ones, as predicted by limited attention theory, assorting with familiar individuals should increase the efficiency in other tasks. We assessed the influence of social familiarity on within-group association behaviour, development and foraging of juvenile life stages of the group-living, plant-inhabiting predatory mite Phytoseiulus persimilis. The observed groups consisted either of mixed-age familiar and unfamiliar juvenile mites or of age-synchronized familiar or unfamiliar juvenile mites or of pairs of familiar or unfamiliar larvae. Overall, familiar mites preferentially grouped together and foraged more efficiently, i.e. needed less prey at similar developmental speed and body size at maturity, than unfamiliar mites. Preferential association of familiar mites was also apparent in the inter-exuviae distances. Social familiarity was established by imprinting in the larval stage, was not cancelled or overridden by later conspecific contacts and persisted into adulthood. Life stage had an effect on grouping with larvae being closer together than nymphal stages. Ultimately, optimized foraging during the developmental phase may relax within-group competition, enhance current and future food supply needed for optimal development and optimize patch exploitation and leaving under limited food.

  13. NIRS prediction of the feed value of temperate forages: efficacy of four calibration strategies.

    Science.gov (United States)

    Andueza, D; Picard, F; Jestin, M; Andrieu, J; Baumont, R

    2011-05-01

    Near infrared reflectance spectroscopy (NIRS) of 924 fresh temperate forages were used to develop calibration models for chemical composition - crude ash (CA) and crude protein (CP) - organic matter digestibility (OMD) and voluntary intake (VI). We used 110 samples to assess the models. Four calibration strategies for determining forage quality were compared: (i) species-specific calibration, (ii) family-specific calibration, (iii) a global procedure and (iv) a local approach. Forage calibration data sets displayed CA values ranging from 52 to 205 g/kg of dry matter (DM), CP values from 50 to 280 g/kg DM, OMD values from 0.48 to 0.85 g/g and VI values from 22.5 to 115.2 g DM/kg metabolic body weight (BW0.75). The calibration models performed well for all the variables except for VI. For CA, local procedure showed lower standard error of prediction (SEP) than species-specific, family-specific or global models. For CP, the calibration models all showed similar SEP values (11.13, 11.08, 11.38 and 11.34 g/kg DM for species-specific, family-specific, global and local approaches). For OMD, the local procedure gave a similar SEP (0.024 g/g) to specific species and global procedures (0.027 g/g) and a lower SEP than the family-specific approach (0.028 g/g). For VI, the local approach and species-specific calibration showed lower SEP (7.08 and 7.16 g/kg BW0.75) than the broad-based calibrations (8.09 and 8.34 g/kg BW0.75 for family-specific model and global procedure, respectively). Local calibration may thus offer a practical way to develop robust universal equations for animal response determinations.

  14. Short communication. Effect of concentrate supplementation and prolificacy on the productive and economic performance of autochthonous sheep breeds fed forage-based diets

    Directory of Open Access Journals (Sweden)

    Raimon Ripoll-Bosch

    2014-11-01

    Full Text Available Sheep farming systems in Spain are experiencing an intensification process, characterised by a general selection criteria of enhancing prolificacy in ewes, and by increasing indoor feeding with concentrates to the detriment of grazing. This study evaluated the effects of concentrate supplementation and prolificacy on productive and economic performance of a local sheep breed in different price scenarios. Ewes were fed forage hay ad libitum, without (in pre-partum period, PRE-HAY; and in post-partum period, POST-HAY or with concentrates (300 g/d in pre-partum period, PRE-CON; and 750 g/d in post-partum period, POST-CON. The inclusion of concentrate during the pre-partum period (last 10 weeks of pregnancy had no effect on the productive performance of the ewes. In contrast, the inclusion of concentrate in the post-partum period (6 weeks, resulted in greater milk yield (1009 vs. 1275 ± 89 g/d, lamb average daily gain (151±12 vs. 225±19 g/d and lamb output (kg of lamb LW weaned. However, the greater productivity thanks to the use of concentrates did not always turn into greatest profitability, since the economic margin was highly influenced by the cost of the diet and extremely subjected to variability in price of concentrates. Hence, the inclusion of concentrates in sheep meat production was not always justified in economic terms. In conclusion, the use of concentrates should only be considered as long as prices of commodities remain low, and inadvisable when prices reach a certain threshold or are subject to certain volatility in markets.

  15. Coarse-grained variables for particle-based models: diffusion maps and animal swarming simulations

    Science.gov (United States)

    Liu, Ping; Safford, Hannah R.; Couzin, Iain D.; Kevrekidis, Ioannis G.

    2014-12-01

    As microscopic (e.g. atomistic, stochastic, agent-based, particle-based) simulations become increasingly prevalent in the modeling of complex systems, so does the need to systematically coarse-grain the information they provide. Before even starting to formulate relevant coarse-grained equations, we need to determine the right macroscopic observables—the right variables in terms of which emergent behavior will be described. This paper illustrates the use of data mining (and, in particular, diffusion maps, a nonlinear manifold learning technique) in coarse-graining the dynamics of a particle-based model of animal swarming. Our computational data-driven coarse-graining approach extracts two coarse (collective) variables from the detailed particle-based simulations, and helps formulate a low-dimensional stochastic differential equation in terms of these two collective variables; this allows the efficient quantification of the interplay of "informed" and "naive" individuals in the collective swarm dynamics. We also present a brief exploration of swarm breakup and use data-mining in an attempt to identify useful predictors for it. In our discussion of the scope and limitations of the approach we focus on the key step of selecting an informative metric, allowing us to usefully compare different particle swarm configurations.

  16. Imaging of Pseudo Oil Base Mud in Environmental Scanning Electron Microscopy Imagerie des boues de forage à base d'huile de substitution par microscopie électronique à balayage ambiant

    Directory of Open Access Journals (Sweden)

    Tricart J. P.

    2006-12-01

    Full Text Available Characterizing pseudo oil base muds (POBM amounts to determining the relationships between the size distribution of droplets and stability of emulsions. Conventional scanning and transmission electron microscope (SEM and TEM have been used to investigate these problems. However, hydrated samples are difficult to handle using such techniques. The Environmental Scanning Electron Microscope (ESEM or Electroscan and the cryogenic techniques have opened the door to the study of wet and non-conductive specimens, and of various liquids or emulsions. ESEM with the cold stage allows us to directly visualize emulsions :- without any preparation or coating;- at different temperatures, by controlling the specimen temperature (between -180°C and -8O°C and pressure (between 400 and 1400 Pa. La caractérisation des boues de forage à base d'huile de substitution (POBM équivaut à définir la relation entre la répartition dimensionnelle des gouttelettes et la stabilité des émulsions. Les microscopes électroniques à balayage (SEM et à transmission (TEM classiques ont été utilisés pour étudier ces problèmes. Toutefois, les échantillons hydratés sont d'un traitement difficile à l'aide de ces techniques. Le microscope environnemental électronique à balayage (ESEM ou electroscan et les techniques cryogéniques ont ouvert la voie à l'étude de spécimens humides et non conducteurs, de liquides et d'émulsions divers. A froid, l'ESEM nous permet de visualiser des émulsions : - sans aucune préparation ou enrobage, - à différentes températures, en régulant la température (entre - 180°C et - 80°C et la pression (entre 400 et 1400 kPa du spécimen. Le présent document se propose de caractériser les boues à base d'huile de substitution et d'étudier : - l'homogénéité de la formulation et la procédure de préparation, - l'influence de la répartition dimensionnelle des gouttelettes sur la stabilité des émulsions.

  17. Foraging strategy switch of a top marine predator according to seasonal resource differences

    Directory of Open Access Journals (Sweden)

    Malcolm Daniel O'Toole

    2015-04-01

    Full Text Available The spatio-temporal variability in marine resources influences the foraging behaviour and success of top marine predators. However, little is known about the links between these animals and ocean productivity, specifically, how plankton density influences their foraging behaviour. Southern elephant seals (Mirounga leonina have two annual at-sea foraging trips: a two month post-breeding foraging trip (Nov – Jan that coincides with elevated summer productivity; and an eight month post-moulting foraging trip (Feb – Oct over winter, when productivity is low. Physical parameters are often used to describe seal habitat, whereas information about important biological parameters is lacking. We used electronic tags deployed on elephant seals during both trips to determine their movement and foraging behaviour. The tags also recorded light, which measured the bio-optical properties of the water column, the bulk of which is presumably influenced by phytoplankton. We investigated the relationship between plankton density and seal foraging behaviour; comparing trends between summer and winter trips. We found a positive relationship between plankton density and foraging behaviour, which did not vary seasonally. We propose that profitable concentrations of seal prey are more likely to coincide with planktonic aggregations, but we also acknowledge that trophic dynamics may shift in response to seasonal trends in productivity. Seal prey (mid-trophic level and plankton (lower-trophic level are expected to overlap in space and time during summer trips when peak phytoplankton blooms occur. In contrast, aggregated patches of lower trophic levels are likely to be more dispersed during winter trips when plankton density is considerably lower and heterogeneous. These results show that southern elephant seals are able to exploit prey resources in different ways throughout the year as demonstrated by the variation observed between seal foraging behaviour and trophic

  18. Determination of Foraging Thresholds and Effects of Application on Energetic Carrying Capacity for Waterfowl

    Science.gov (United States)

    2015-01-01

    Energetic carrying capacity of habitats for wildlife is a fundamental concept used to better understand population ecology and prioritize conservation efforts. However, carrying capacity can be difficult to estimate accurately and simplified models often depend on many assumptions and few estimated parameters. We demonstrate the complex nature of parameterizing energetic carrying capacity models and use an experimental approach to describe a necessary parameter, a foraging threshold (i.e., density of food at which animals no longer can efficiently forage and acquire energy), for a guild of migratory birds. We created foraging patches with different fixed prey densities and monitored the numerical and behavioral responses of waterfowl (Anatidae) and depletion of foods during winter. Dabbling ducks (Anatini) fed extensively in plots and all initial densities of supplemented seed were rapidly reduced to 10 kg/ha and other natural seeds and tubers combined to 170 kg/ha, despite different starting densities. However, ducks did not abandon or stop foraging in wetlands when seed reduction ceased approximately two weeks into the winter-long experiment nor did they consistently distribute according to ideal-free predictions during this period. Dabbling duck use of experimental plots was not related to initial seed density, and residual seed and tuber densities varied among plant taxa and wetlands but not plots. Herein, we reached several conclusions: 1) foraging effort and numerical responses of dabbling ducks in winter were likely influenced by factors other than total food densities (e.g., predation risk, opportunity costs, forager condition), 2) foraging thresholds may vary among foraging locations, and 3) the numerical response of dabbling ducks may be an inconsistent predictor of habitat quality relative to seed and tuber density. We describe implications on habitat conservation objectives of using different foraging thresholds in energetic carrying capacity models and

  19. Mechanisms of Acupuncture Effect on Alzheimer's Disease in Animal- Based Researches.

    Science.gov (United States)

    Cao, Yan; Zhang, Li-Wen; Wang, Jian; Du, Si-Qi; Xiao, Ling-Yong; Tu, Jian-Feng; Liu, Cun-Zhi

    2016-01-01

    Alzheimer's disease is the most common type of dementia in the aging population worldwide. The etiology and treatment of Alzheimer's disease are still not very clear. Finding a new treatment is urgent due to the increasing population aging. Acupuncture has been practicing in China for more than 3000 years and reported to be beneficial in treating cognitive impairment of Alzheimer's disease. This paper reviews the recent development on the effect of acupuncture on Alzheimer's disease in animal-based researches. It is suggested that acupuncture improves cognitive function of Alzheimer's disease by regulating glucose metabolism, enhancing neurotransmission as well as reducing oxidative stress, Aβ protein deposition, and neuronal apoptosis. However, it is still difficult to clarify which specific signaling pathway contributes to the acupuncture effect. Better designed studies are recommended to investigate the effects of acupuncture on Alzheimer's disease.

  20. Implementation and Application of PSF-Based EPI Distortion Correction to High Field Animal Imaging

    Directory of Open Access Journals (Sweden)

    Dominik Paul

    2009-01-01

    Full Text Available The purpose of this work is to demonstrate the functionality and performance of a PSF-based geometric distortion correction for high-field functional animal EPI. The EPI method was extended to measure the PSF and a postprocessing chain was implemented in Matlab for offline distortion correction. The correction procedure was applied to phantom and in vivo imaging of mice and rats at 9.4T using different SE-EPI and DWI-EPI protocols. Results show the significant improvement in image quality for single- and multishot EPI. Using a reduced FOV in the PSF encoding direction clearly reduced the acquisition time for PSF data by an acceleration factor of 2 or 4, without affecting the correction quality.

  1. Design Virtual Reality Scene Roam for Tour Animations Base on VRML and Java

    Science.gov (United States)

    Cao, Zaihui; hu, Zhongyan

    Virtual reality has been involved in a wide range of academic and commercial applications. It can give users a natural feeling of the environment by creating realistic virtual worlds. Implementing a virtual tour through a model of a tourist area on the web has become fashionable. In this paper, we present a web-based application that allows a user to, walk through, see, and interact with a fully three-dimensional model of the tourist area. Issues regarding navigation and disorientation areaddressed and we suggest a combination of the metro map and an intuitive navigation system. Finally we present a prototype which implements our ideas. The application of VR techniques integrates the visualization and animation of the three dimensional modelling to landscape analysis. The use of the VRML format produces the possibility to obtain some views of the 3D model and to explore it in real time. It is an important goal for the spatial information sciences.

  2. Development and evaluation of web-based animated pedagogical agents for facilitating critical thinking in nursing.

    Science.gov (United States)

    Morey, Diane J

    2012-01-01

    The purpose of this study was to evaluate the effectiveness of Web-based animated pedagogical agents on critical thinking among nursing students. A pedagogical agent or virtual character provides a possible innovative tool for critical thinking through active engagement of students by asking questions and providing feedback about a series of nursing case studies. This mixed methods experimental study used a pretest, posttest design with a control group. ANCOVA demonstrated no significant difference between the groups on the Critical Thinking Process Test. Pre- and post-think-alouds were analyzed using a rating tool and rubric for the presence of eight cognitive processes, level of critical thinking, and for accuracy of nursing diagnosis, conclusions, and evaluation. Chi-square analyses for each group revealed a significant difference for improvement of the critical thinking level and correct conclusions from pre-think-aloud to post-think-aloud, but only the pedagogical agent group had a significant result for appropriate evaluations.

  3. Trapline foraging by pollinators: its ontogeny, economics and possible consequences for plants.

    Science.gov (United States)

    Ohashi, Kazuharu; Thomson, James D

    2009-06-01

    Trapline foraging (repeated sequential visits to a series of feeding locations) has been often observed in pollinators collecting nectar or pollen from flowers. Although field studies on bumble-bees and hummingbirds have clarified fundamental aspects of this behaviour, trapline foraging still poses several difficult questions from the perspectives of both animals and plants. These questions include whether and how traplining improves foraging performance, how animals develop traplines with accumulating foraging experience, and how traplining affects pollen flow or plant reproduction. First, we review our previous work performed by using computer simulations and indoor flight-cage experiments with bumble-bees foraging from arrays of automated feeders. Our findings include the following: (1) traplining benefits foragers that are competing for resources that replenish in a decelerating way, (2) traplining is a learned behaviour that develops over a period of hours and (3) the establishment of traplines could be hampered by spatial configuration of plants such as zigzags. Second, using a simulation model linking pollinator movement and pollen transfer, we consider how service by pollinators with different foraging patterns (searchers or trapliners) would affect pollen flow. Traplining increases mating distance and mate diversity, and reduces 'iterogamy' (self-pollination caused by return visits) at the population level. Furthermore, increased visitation rates can have opposite effects on the reproductive success of a plant, depending on whether the visitors are traplining or searching. Finally, we discuss possible consequences of traplining for plants in the light of new experimental work and modelling. We suggest that trapline foraging by pollinators increases variation among plant populations in genetic diversity, inbreeding depression and contributions of floral traits to plant fitness, which should in turn affect the rates and directions of floral evolution. More

  4. Ruminal fermentation of Anti-methanogenic Nitrate- and Nitro-Containing Forages In Vitro

    Directory of Open Access Journals (Sweden)

    Robin C. Anderson

    2016-08-01

    Full Text Available Nitrate, 3-nitro-1-propionic acid (NPA and 3-nitro-1-propanol (NPOH can accumulate in forages and be poisonous to animals if consumed in high enough amounts. These chemicals are also recognized as potent anti-methanogenic compounds, but plants naturally containing these chemicals have been studied little in this regard. Presently, we found that nitrate-, NPA- or NPOH-containing forages effectively decreased methane production, by 35 to 87%, during in vitro fermentation by mixed cultures of ruminal microbes compared to fermentation by cultures incubated similarly with alfalfa. Methane production was further decreased during incubation of mixed cultures also inoculated with Denitrobacterium detoxificans, a ruminal bacterium known to metabolize nitrate, NPA and NPOH. Inhibition of methanogens within the mixed cultures was greatest with the NPA- and NPOH-containing forages. Hydrogen accumulated in all the mixed cultures incubated with forages containing nitrate, NPA or NPOH but was dramatically higher, exceeding 40 µmol hydrogen/mL, in mixed cultures incubated with NPA-containing forage but not inoculated with D. detoxificans. This possibly reflects the inhibition of hydrogenase-catalyzed uptake of hydrogen produced via conversion of 50 µmol added formate per mL to hydrogen. Accumulations of volatile fatty acids revealed compensatory changes in fermentation in mixed cultures incubated with the nitrate-, NPA- and NPOH-containing forages as evidenced by lower accumulations of acetate, and in some cases higher accumulations of butyrate and lower accumulations of ammonia, iso-buytrate and iso-valerate compared to cultures incubated with alfalfa. Results reveal that nitrate, NPA and NPOH that accumulate naturally in forages can be made available within ruminal incubations to inhibit methanogenesis. Further research is warranted to determine if diets can be formulated with nitrate-, NPA- and NPOH-containing forages to achieve efficacious mitigation in

  5. Ruminal Fermentation of Anti-Methanogenic Nitrate- and Nitro-Containing Forages In Vitro

    Science.gov (United States)

    Anderson, Robin C.; Ripley, Laura H.; Bowman, Jan G. P.; Callaway, Todd R.; Genovese, Kenneth J.; Beier, Ross C.; Harvey, Roger B.; Nisbet, David J.

    2016-01-01

    Nitrate, 3-nitro-1-propionic acid (NPA) and 3-nitro-1-propanol (NPOH) can accumulate in forages and be poisonous to animals if consumed in high enough amounts. These chemicals are also recognized as potent anti-methanogenic compounds, but plants naturally containing these chemicals have been studied little in this regard. Presently, we found that nitrate-, NPA-, or NPOH-containing forages effectively decreased methane production, by 35–87%, during in vitro fermentation by mixed cultures of ruminal microbes compared to fermentation by cultures incubated similarly with alfalfa. Methane production was further decreased during the incubation of mixed cultures also inoculated with Denitrobacterium detoxificans, a ruminal bacterium known to metabolize nitrate, NPA, and NPOH. Inhibition of methanogens within the mixed cultures was greatest with the NPA- and NPOH-containing forages. Hydrogen accumulated in all the mixed cultures incubated with forages containing nitrate, NPA or NPOH and was dramatically higher, exceeding 40 μmol hydrogen/mL, in mixed cultures incubated with NPA-containing forage but not inoculated with D. detoxificans. This possibly reflects the inhibition of hydrogenase-catalyzed uptake of hydrogen produced via conversion of 50 μmol added formate per milliliter to hydrogen. Accumulations of volatile fatty acids revealed compensatory changes in fermentation in mixed cultures incubated with the nitrate-, NPA-, and NPOH-containing forages as evidenced by lower accumulations of acetate, and in some cases, higher accumulations of butyrate and lower accumulations of ammonia, iso-buytrate, and iso-valerate compared to cultures incubated with alfalfa. Results reveal that nitrate, NPA, and NPOH that accumulate naturally in forages can be made available within ruminal incubations to inhibit methanogenesis. Further research is warranted to determine if diets can be formulated with nitrate-, NPA-, and NPOH-containing forages to achieve efficacious mitigation

  6. Ruminal Fermentation of Anti-Methanogenic Nitrate- and Nitro-Containing Forages In Vitro.

    Science.gov (United States)

    Anderson, Robin C; Ripley, Laura H; Bowman, Jan G P; Callaway, Todd R; Genovese, Kenneth J; Beier, Ross C; Harvey, Roger B; Nisbet, David J

    2016-01-01

    Nitrate, 3-nitro-1-propionic acid (NPA) and 3-nitro-1-propanol (NPOH) can accumulate in forages and be poisonous to animals if consumed in high enough amounts. These chemicals are also recognized as potent anti-methanogenic compounds, but plants naturally containing these chemicals have been studied little in this regard. Presently, we found that nitrate-, NPA-, or NPOH-containing forages effectively decreased methane production, by 35-87%, during in vitro fermentation by mixed cultures of ruminal microbes compared to fermentation by cultures incubated similarly with alfalfa. Methane production was further decreased during the incubation of mixed cultures also inoculated with Denitrobacterium detoxificans, a ruminal bacterium known to metabolize nitrate, NPA, and NPOH. Inhibition of methanogens within the mixed cultures was greatest with the NPA- and NPOH-containing forages. Hydrogen accumulated in all the mixed cultures incubated with forages containing nitrate, NPA or NPOH and was dramatically higher, exceeding 40 μmol hydrogen/mL, in mixed cultures incubated with NPA-containing forage but not inoculated with D. detoxificans. This possibly reflects the inhibition of hydrogenase-catalyzed uptake of hydrogen produced via conversion of 50 μmol added formate per milliliter to hydrogen. Accumulations of volatile fatty acids revealed compensatory changes in fermentation in mixed cultures incubated with the nitrate-, NPA-, and NPOH-containing forages as evidenced by lower accumulations of acetate, and in some cases, higher accumulations of butyrate and lower accumulations of ammonia, iso-buytrate, and iso-valerate compared to cultures incubated with alfalfa. Results reveal that nitrate, NPA, and NPOH that accumulate naturally in forages can be made available within ruminal incubations to inhibit methanogenesis. Further research is warranted to determine if diets can be formulated with nitrate-, NPA-, and NPOH-containing forages to achieve efficacious mitigation in

  7. A DNA-based registry for all animal species: the barcode index number (BIN system.

    Directory of Open Access Journals (Sweden)

    Sujeevan Ratnasingham

    Full Text Available Because many animal species are undescribed, and because the identification of known species is often difficult, interim taxonomic nomenclature has often been used in biodiversity analysis. By assigning individuals to presumptive species, called operational taxonomic units (OTUs, these systems speed investigations into the patterning of biodiversity and enable studies that would otherwise be impossible. Although OTUs have conventionally been separated through their morphological divergence, DNA-based delineations are not only feasible, but have important advantages. OTU designation can be automated, data can be readily archived, and results can be easily compared among investigations. This study exploits these attributes to develop a persistent, species-level taxonomic registry for the animal kingdom based on the analysis of patterns of nucleotide variation in the barcode region of the cytochrome c oxidase I (COI gene. It begins by examining the correspondence between groups of specimens identified to a species through prior taxonomic work and those inferred from the analysis of COI sequence variation using one new (RESL and four established (ABGD, CROP, GMYC, jMOTU algorithms. It subsequently describes the implementation, and structural attributes of the Barcode Index Number (BIN system. Aside from a pragmatic role in biodiversity assessments, BINs will aid revisionary taxonomy by flagging possible cases of synonymy, and by collating geographical information, descriptive metadata, and images for specimens that are likely to belong to the same species, even if it is undescribed. More than 274,000 BIN web pages are now available, creating a biodiversity resource that is positioned for rapid growth.

  8. Characterizing habitat suitability for a central-place forager in a dynamic marine environment.

    Science.gov (United States)

    Briscoe, Dana K; Fossette, Sabrina; Scales, Kylie L; Hazen, Elliott L; Bograd, Steven J; Maxwell, Sara M; McHuron, Elizabeth A; Robinson, Patrick W; Kuhn, Carey; Costa, Daniel P; Crowder, Larry B; Lewison, Rebecca L

    2018-03-01

    Characterizing habitat suitability for a marine predator requires an understanding of the environmental heterogeneity and variability over the range in which a population moves during a particular life cycle. Female California sea lions ( Zalophus californianus ) are central-place foragers and are particularly constrained while provisioning their young. During this time, habitat selection is a function of prey availability and proximity to the rookery, which has important implications for reproductive and population success. We explore how lactating females may select habitat and respond to environmental variability over broad spatial and temporal scales within the California Current System. We combine near-real-time remotely sensed satellite oceanography, animal tracking data ( n  = 72) from November to February over multiple years (2003-2009) and Generalized Additive Mixed Models (GAMMs) to determine the probability of sea lion occurrence based on environmental covariates. Results indicate that sea lion presence is associated with cool ( habitat maps generated from these biophysical associations suggest winter foraging areas are spatially consistent in the nearshore and offshore environments, except during the 2004-2005 winter, which coincided with an El Niño event. Here, we show how a species distribution model can provide broadscale information on the distribution of female California sea lions during an important life history stage and its implications for population dynamics and spatial management.

  9. Web-Based Surveillance Systems for Human, Animal, and Plant Diseases.

    Science.gov (United States)

    Madoff, Lawrence C; Li, Annie

    2014-02-01

    The emergence of infectious diseases, caused by novel pathogens or the spread of existing ones to new populations and regions, represents a continuous threat to humans and other species. The early detection of emerging human, animal, and plant diseases is critical to preventing the spread of infection and protecting the health of our species and environment. Today, more than 75% of emerging infectious diseases are estimated to be zoonotic and capable of crossing species barriers and diminishing food supplies. Traditionally, surveillance of diseases has relied on a hierarchy of health professionals that can be costly to build and maintain, leading to a delay or interruption in reporting. However, Internet-based surveillance systems bring another dimension to epidemiology by utilizing technology to collect, organize, and disseminate information in a more timely manner. Partially and fully automated systems allow for earlier detection of disease outbreaks by searching for information from both formal sources (e.g., World Health Organization and government ministry reports) and informal sources (e.g., blogs, online media sources, and social networks). Web-based applications display disparate information online or disperse it through e-mail to subscribers or the general public. Web-based early warning systems, such as ProMED-mail, the Global Public Health Intelligence Network (GPHIN), and Health Map, have been able to recognize emerging infectious diseases earlier than traditional surveillance systems. These systems, which are continuing to evolve, are now widely utilized by individuals, humanitarian organizations, and government health ministries.

  10. USE OF GUACIMO (Guazuma ulmifolia Lam. AS A FORAGE SOURCE FOR EXTENSIVE LIVESTOCK PRODUCTION IN A TROPICAL AREA OF MEXICO

    Directory of Open Access Journals (Sweden)

    Martha Elena Nava-Tablada

    2009-02-01

    Full Text Available The objective was to study the traditional uses of guacimo (Guazuma ulmifolia Lam, compared to other local forage resources for livestock. The expectative of farmers on the use of trees as alternative sources of forage in Angostillo, Paso de Ovejas, Veracruz, Mexico was also investigated. Data was collected through interviews and direct observation. All farmers practice ranching and 85% combine animal production with crop cultivation; allocating 40% of their land to corn and 60% to dual purpose cattle production. The principal uses of guacimo are as forage, firewood, timber, shade, and living fence posts. Guacimo has the highest value as forage compared to other local fodder trees such as guaje de indio (Leucaena lanceolata S. Watson, espino (Acacia cavenia Mol. and huizache (A. farnesiana Willd.. Farmers showed interest in establishing silvopastoral systems including forage banks using guacimo. However, they foresaw limitations due to a lack of consulting, agronomic training and financial support to establish the crops.

  11. The development of the animal production potential of the dry grass ...

    African Journals Online (AJOL)

    The dry grass bush communities of the Eastern Cape are comprehensive forage sources and the development of the animal production potential is discussed. Two clearly defined forage sources are available which make it imperative to include browsers as well as grazers in the animal production system. Guidelines to the ...

  12. Testing optimal foraging theory in a penguin-krill system.

    Science.gov (United States)

    Watanabe, Yuuki Y; Ito, Motohiro; Takahashi, Akinori

    2014-03-22

    Food is heterogeneously distributed in nature, and understanding how animals search for and exploit food patches is a fundamental challenge in ecology. The classic marginal value theorem (MVT) formulates optimal patch residence time in response to patch quality. The MVT was generally proved in controlled animal experiments; however, owing to the technical difficulties in recording foraging behaviour in the wild, it has been inadequately examined in natural predator-prey systems, especially those in the three-dimensional marine environment. Using animal-borne accelerometers and video cameras, we collected a rare dataset in which the behaviour of a marine predator (penguin) was recorded simultaneously with the capture timings of mobile, patchily distributed prey (krill). We provide qualitative support for the MVT by showing that (i) krill capture rate diminished with time in each dive, as assumed in the MVT, and (ii) dive duration (or patch residence time, controlled for dive depth) increased with short-term, dive-scale krill capture rate, but decreased with long-term, bout-scale krill capture rate, as predicted from the MVT. Our results demonstrate that a single environmental factor (i.e. patch quality) can have opposite effects on animal behaviour depending on the time scale, emphasizing the importance of multi-scale approaches in understanding complex foraging strategies.

  13. Full modelling of the MOSAIC animal PET system based on the GATE Monte Carlo simulation code

    International Nuclear Information System (INIS)

    Merheb, C; Petegnief, Y; Talbot, J N

    2007-01-01

    within 9%. For a 410-665 keV energy window, the measured sensitivity for a centred point source was 1.53% and mouse and rat scatter fractions were respectively 12.0% and 18.3%. The scattered photons produced outside the rat and mouse phantoms contributed to 24% and 36% of total simulated scattered coincidences. Simulated and measured single and prompt count rates agreed well for activities up to the electronic saturation at 110 MBq for the mouse and rat phantoms. Volumetric spatial resolution was 17.6 μL at the centre of the FOV with differences less than 6% between experimental and simulated spatial resolution values. The comprehensive evaluation of the Monte Carlo modelling of the Mosaic(TM) system demonstrates that the GATE package is adequately versatile and appropriate to accurately describe the response of an Anger logic based animal PET system

  14. U.S. Dairy Forage Research Center

    Data.gov (United States)

    Federal Laboratory Consortium — Vision: Leading the world in integrated dairy forage systems research. Mission: Providing dairy industry solutions for food security, environmental sustainability,...

  15. U.S. DAIRY FORAGE RESEARCH CENTER

    Data.gov (United States)

    Federal Laboratory Consortium — Vision: Leading the world in integrated dairy forage systems research. Mission: Providing dairy industry solutions for food security, environmental sustainability,...

  16. Computer Animation Complete All-in-One; Learn Motion Capture, Characteristic, Point-Based, and Maya Winning Techniques

    CERN Document Server

    Parent, Rick

    2009-01-01

    A compilation of key chapters from the top MK computer animation books available today - in the areas of motion capture, facial features, solid spaces, fluids, gases, biology, point-based graphics, and Maya. The chapters provide CG Animators with an excellent sampling of essential techniques that every 3D artist needs to create stunning and versatile images. Animators will be able to master myriad modeling, rendering, and texturing procedures with advice from MK's best and brightest authors. Learn hundreds of tips, tricks, shortcuts and more - all within the covers of one complete, inspiring r

  17. Recent developments in forage evaluation with special reference to practical applications

    Directory of Open Access Journals (Sweden)

    P. HUHTANEN

    2008-12-01

    Full Text Available The present re-evaluation of a dataset of systematically collected laboratory analyses and in vivo digestibility information for several types of silages gives convincing evidence of the biological weaknesses of feed characterisation based on the proximate feed analysis. The problems include intrinsic failures of the analysis in describing cause-response relationships between forage composition and digestibility, and heavy dependency of the equations on forage specific and environmental factors. It is concluded that proximate analysis is not suitable for characterisation of neither forages nor concentrate feedstuffs. In vitro pepsin-cellulase solubility of organic matter (OMS and concentration of indigestible neutral detergent fibre (iNDF predicted forage organic matter digestibility (OMD with an acceptable accuracy for practical feed evaluation purposes provided that forage type dependent correction equations were employed. The revised detergent system dividing forage dry matter (DM into almost completely available neutral detergent solubles (NDS, and insoluble residue (neutral detergent fibre, NDF shows potential for future development. The combined use of long-term in situ ruminal incubation and NDF fractionation can be used to divide forage DM into three biologically meaningful fractions: NDS, iNDF and potentially digestible NDF (pdNDF. The summative models can then be used to predict forage D-value, i.e. apparently digestible organic matter in forage (g kg-1 DM. The models sum digestible NDS, which can be determined by Lucas equation, and digestible NDF (dNDF, which is the amount of pdNDF that is actually digested during any specific fermentation or retention time. Forage type specific summative models were as good as regression equations based on OMS or iNDF in predicting forage D-value and general summative models gave better results than general equations based on iNDF and especially OMS. If the goal is to reduce prediction error of D

  18. Movement activity based classification of animal behaviour with an application to data from cheetah (Acinonyx jubatus).

    Science.gov (United States)

    Grünewälder, Steffen; Broekhuis, Femke; Macdonald, David Whyte; Wilson, Alan Martin; McNutt, John Weldon; Shawe-Taylor, John; Hailes, Stephen

    2012-01-01

    We propose a new method, based on machine learning techniques, for the analysis of a combination of continuous data from dataloggers and a sampling of contemporaneous behaviour observations. This data combination provides an opportunity for biologists to study behaviour at a previously unknown level of detail and accuracy; however, continuously recorded data are of little use unless the resulting large volumes of raw data can be reliably translated into actual behaviour. We address this problem by applying a Support Vector Machine and a Hidden-Markov Model that allows us to classify an animal's behaviour using a small set of field observations to calibrate continuously recorded activity data. Such classified data can be applied quantitatively to the behaviour of animals over extended periods and at times during which observation is difficult or impossible. We demonstrate the usefulness of the method by applying it to data from six cheetah (Acinonyx jubatus) in the Okavango Delta, Botswana. Cumulative activity data scores were recorded every five minutes by accelerometers embedded in GPS radio-collars for around one year on average. Direct behaviour sampling of each of the six cheetah were collected in the field for comparatively short periods. Using this approach we are able to classify each five minute activity score into a set of three key behaviour (feeding, mobile and stationary), creating a continuous behavioural sequence for the entire period for which the collars were deployed. Evaluation of our classifier with cross-validation shows the accuracy to be 83%-94%, but that the accuracy for individual classes is reduced with decreasing sample size of direct observations. We demonstrate how these processed data can be used to study behaviour identifying seasonal and gender differences in daily activity and feeding times. Results given here are unlike any that could be obtained using traditional approaches in both accuracy and detail.

  19. Movement activity based classification of animal behaviour with an application to data from cheetah (Acinonyx jubatus.

    Directory of Open Access Journals (Sweden)

    Steffen Grünewälder

    Full Text Available We propose a new method, based on machine learning techniques, for the analysis of a combination of continuous data from dataloggers and a sampling of contemporaneous behaviour observations. This data combination provides an opportunity for biologists to study behaviour at a previously unknown level of detail and accuracy; however, continuously recorded data are of little use unless the resulting large volumes of raw data can be reliably translated into actual behaviour. We address this problem by applying a Support Vector Machine and a Hidden-Markov Model that allows us to classify an animal's behaviour using a small set of field observations to calibrate continuously recorded activity data. Such classified data can be applied quantitatively to the behaviour of animals over extended periods and at times during which observation is difficult or impossible. We demonstrate the usefulness of the method by applying it to data from six cheetah (Acinonyx jubatus in the Okavango Delta, Botswana. Cumulative activity data scores were recorded every five minutes by accelerometers embedded in GPS radio-collars for around one year on average. Direct behaviour sampling of each of the six cheetah were collected in the field for comparatively short periods. Using this approach we are able to classify each five minute activity score into a set of three key behaviour (feeding, mobile and stationary, creating a continuous behavioural sequence for the entire period for which the collars were deployed. Evaluation of our classifier with cross-validation shows the accuracy to be 83%-94%, but that the accuracy for individual classes is reduced with decreasing sample size of direct observations. We demonstrate how these processed data can be used to study behaviour identifying seasonal and gender differences in daily activity and feeding times. Results given here are unlike any that could be obtained using traditional approaches in both accuracy and detail.

  20. [Quantification of astringency for traditional Chinese medicine based on animal preference index and electronic tongue].

    Science.gov (United States)

    Han, Xue; Jiang, Hong; Lin, Jun-Zhi; Han, Li; Xiong, Xi; Jiao, Jiao-Jiao; Zhang, Ying-Ying; Zhang, Ding-Kun; Yang, Ming

    2017-02-01

    Current evaluation method for astringency is mainly focused on human sensory evaluation. However, it is subjective, vague, and short of assessment indicators for objective quantification. In this paper, the quantification method for astringent intensity of traditional Chinese medicine was established based on the animal preference index and electronic tongue in vitro and in vivo. Firstly, the standard substance of astringency, tannic acid, was used for the methodology optimization and validation of two-bottle preference test. It was determined that the standard experimental animals were female rats of 140-180 g. The functional relationship between concentration of tannic acid and preference index was obtained Y= ln(1.682 6-0.441 66X), r=0.997 3. Then the typical astringent Chinese herbs Chebulae Fructus, Ardisiae Japonicae Herba, Canarii Fructus, Catechu, and Arecae Pericarpium were evaluated by the optimized method. Their corresponding concentration of tannic acid was converted by the concentration-preference index relationship through preference index. Their astringency was equivalent to 0.56, 0.29, 0.24, 0.34, 0.25 g•L⁻¹ tannic acid. Finally, the results were verified by electronic tongue. The correction analysis between Euclidean distance in PCA and preference index and concentration of tannic acid converted by samples showed a high correlation through pearson correlation analysis. The above results indicated that the method was objective, true and reliable. The method provided a reliable tool for the quantification of astringency and evaluation of taste masking effect for Chinese medicines, and also offered a new idea and model for the quantification of taste in the pharmaceutical and food fields. Copyright© by the Chinese Pharmaceutical Association.

  1. Handling interference effects on foraging with bucket brigades.

    Science.gov (United States)

    Lee, Wonki; Kim, DaeEun

    2017-10-16

    Many kinds of bio-inspired tasks have been tested with swarm robotics and task partitioning is one of the challenging subjects. In nature, it is well known that some colonies of social insects such as honeybees, termites, and ants use task partitioning strategies for their survival. In this paper, we demonstrate an effect of the task partitioning strategy called bucket brigade, which uses the direct transfer of materials or food between a pair of workers. We propose a task partitioning strategy based on the moving speeds of agents for the foraging task. We test various environmental conditions and compare the performance between task partitioning groups and non-partitioning groups. The experimental results show that task partitioning may not always be the best solution for foraging performance. However, when there exists a transfer bottleneck at a central location such as the entrance of the nest, task partitioning can be an effective strategy for reducing the traffic jam and improving the overall foraging performance of a group. The bucket brigade sequenced from the slowest agents (near the food source) to the fastest agents (near the nest) can particularly improve performance significantly in the region with traffic congestion near the nest. Generally, many social insect colonies consist of a number of members, and the entrances of colony nests always suffer from heavy traffic congestion. Our experimental results support the hypothesis that several social insects use one of the task partitioning strategies based on bucket brigades in their foraging tasks.

  2. Animal experimentation.

    Science.gov (United States)

    Kolar, Roman

    2006-01-01

    Millions of animals are used every year in often times extremely painful and distressing scientific procedures. Legislation of animal experimentation in modern societies is based on the supposition that this is ethically acceptable when certain more or less defined formal (e.g. logistical, technical) demands and ethical principles are met. The main parameters in this context correspond to the "3Rs" concept as defined by Russel and Burch in 1959, i.e. that all efforts to replace, reduce and refine experiments must be undertaken. The licensing of animal experiments normally requires an ethical evaluation process, often times undertaken by ethics committees. The serious problems in putting this idea into practice include inter alia unclear conditions and standards for ethical decisions, insufficient management of experiments undertaken for specific (e.g. regulatory) purposes, and conflicts of interest of ethics committees' members. There is an ongoing societal debate about ethical issues of animal use in science. Existing EU legislation on animal experimentation for cosmetics testing is an example of both the public will for setting clear limits to animal experiments and the need to further critically examine other fields and aspects of animal experimentation.

  3. Animal Bioacoustics

    Science.gov (United States)

    Fletcher, Neville H.

    Animals rely upon their acoustic and vibrational senses and abilities to detect the presence of both predators and prey and to communicate with members of the same species. This chapter surveys the physical bases of these abilities and their evolutionary optimization in insects, birds, and other land animals, and in a variety of aquatic animals other than cetaceans, which are treated in Chap. 20. While there are many individual variations, and some animals devote an immense fraction of their time and energy to acoustic communication, there are also many common features in their sound production and in the detection of sounds and vibrations. Excellent treatments of these matters from a biological viewpoint are given in several notable books [19.1,2] and collections of papers [19.3,4,5,6,7,8], together with other more specialized books to be mentioned in the following sections, but treatments from an acoustical viewpoint [19.9] are rare. The main difference between these two approaches is that biological books tend to concentrate on anatomical and physiological details and on behavioral outcomes, while acoustical books use simplified anatomical models and quantitative analysis to model vocalization frequency scaling in animals hearing sound production animal animal biological biological bioacoustics whole-system behavior. This latter is the approach to be adopted here.

  4. Development of a Si-PM-based high-resolution PET system for small animals

    International Nuclear Information System (INIS)

    Yamamoto, Seiichi; Imaizumi, Masao; Watabe, Tadashi; Shimosegawa, Eku; Hatazawa, Jun; Watabe, Hiroshi; Kanai, Yasukazu

    2010-01-01

    A Geiger-mode avalanche photodiode (Si-PM) is a promising photodetector for PET, especially for use in a magnetic resonance imaging (MRI) system, because it has high gain and is less sensitive to a static magnetic field. We developed a Si-PM-based depth-of-interaction (DOI) PET system for small animals. Hamamatsu 4 x 4 Si-PM arrays (S11065-025P) were used for its detector blocks. Two types of LGSO scintillator of 0.75 mol% Ce (decay time: ∼45 ns; 1.1 mm x 1.2 mm x 5 mm) and 0.025 mol% Ce (decay time: ∼31 ns; 1.1 mm x 1.2 mm x 6 mm) were optically coupled in the DOI direction to form a DOI detector, arranged in a 11 x 9 matrix, and optically coupled to the Si-PM array. Pulse shape analysis was used for the DOI detection of these two types of LGSOs. Sixteen detector blocks were arranged in a 68 mm diameter ring to form the PET system. Spatial resolution was 1.6 mm FWHM and sensitivity was 0.6% at the center of the field of view. High-resolution mouse and rat images were successfully obtained using the PET system. We confirmed that the developed Si-PM-based PET system is promising for molecular imaging research.

  5. Development of a Si-PM-based high-resolution PET system for small animals

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, Seiichi [Kobe City College of Technology, Kobe (Japan); Imaizumi, Masao; Watabe, Tadashi; Shimosegawa, Eku; Hatazawa, Jun [Department of Nuclear Medicine and Tracer Kinetics, Osaka University Graduate School of Medicine, Osaka (Japan); Watabe, Hiroshi; Kanai, Yasukazu, E-mail: s-yama@kobe-kosen.ac.j [Department of Molecular Imaging in Medicine, Osaka University Graduate School of Medicine, Osaka (Japan)

    2010-10-07

    A Geiger-mode avalanche photodiode (Si-PM) is a promising photodetector for PET, especially for use in a magnetic resonance imaging (MRI) system, because it has high gain and is less sensitive to a static magnetic field. We developed a Si-PM-based depth-of-interaction (DOI) PET system for small animals. Hamamatsu 4 x 4 Si-PM arrays (S11065-025P) were used for its detector blocks. Two types of LGSO scintillator of 0.75 mol% Ce (decay time: {approx}45 ns; 1.1 mm x 1.2 mm x 5 mm) and 0.025 mol% Ce (decay time: {approx}31 ns; 1.1 mm x 1.2 mm x 6 mm) were optically coupled in the DOI direction to form a DOI detector, arranged in a 11 x 9 matrix, and optically coupled to the Si-PM array. Pulse shape analysis was used for the DOI detection of these two types of LGSOs. Sixteen detector blocks were arranged in a 68 mm diameter ring to form the PET system. Spatial resolution was 1.6 mm FWHM and sensitivity was 0.6% at the center of the field of view. High-resolution mouse and rat images were successfully obtained using the PET system. We confirmed that the developed Si-PM-based PET system is promising for molecular imaging research.

  6. Same size--same niche? Foraging niche separation between sympatric juvenile Galapagos sea lions and adult Galapagos fur seals.

    Science.gov (United States)

    Jeglinski, Jana W E; Goetz, Kimberley T; Werner, Christiane; Costa, Daniel P; Trillmich, Fritz

    2013-05-01

    1. In vertebrates, patterns of resource utilization change throughout development according to age- and or size-specific abilities and requirements. Thus, interspecific competition affects different age classes differently. 2. Adults of sympatric species often show distinct foraging niche segregation, but juvenile resource use might overlap with adult competitors of similar body size. Resultant negative effects on juveniles can have important consequences for population dynamics, yet such interactions have received little attention in studies of mammalian communities. 3. Using GPS tracking devices, time-depth recorders and stable isotope data, we compared diving depth, activity time, trophic position and foraging habitat characteristics to investigate foraging niche overlap between similar-sized sympatric juvenile Galapagos sea lions (Zalophus wollebaeki) and adult Galapagos fur seals (Arctocephalus galapagoensis) and compared each group with much larger-bodied adult Galapagos sea lions. 4. We found little indication for direct competition but a complex pattern of foraging niche segregation: juvenile sea lions and adult fur seals dived to shallow depths at night, but foraged in different habitats with limited spatial overlap. Conversely, juvenile and adult sea lions employed different foraging patterns, but their foraging areas overlapped almost completely. 5. Consistency of foraging habitat characteristics between juvenile and adult sea lions suggests that avoidance of competition may be important in shaping foraging habitat utilization. Resultant specialization on a limited habitat could contribute to low sea lion numbers that contrast with high fur seal abundance. Our data suggest that exploitation by multiple predators within spatially restricted foraging ranges of juveniles might negatively impact juvenile foraging success and ultimately influence population dynamics. © 2013 The Authors. Journal of Animal Ecology © 2013 British Ecological Society.

  7. Linking human diseases to animal models using ontology-based phenotype annotation.

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    Nicole L Washington

    2009-11-01

    Full Text Available Scientists and clinicians who study genetic alterations and disease have traditionally described phenotypes in natural language. The considerable variation in these free-text descriptions has posed a hindrance to the important task of identifying candidate genes and models for human diseases and indicates the need for a computationally tractable method to mine data resources for mutant phenotypes. In this study, we tested the hypothesis that ontological annotation of disease phenotypes will facilitate the discovery of new genotype-phenotype relationships within and across species. To describe phenotypes using ontologies, we used an Entity-Quality (EQ methodology, wherein the affected entity (E and how it is affected (Q are recorded using terms from a variety of ontologies. Using this EQ method, we annotated the phenotypes of 11 gene-linked human diseases described in Online Mendelian Inheritance in Man (OMIM. These human annotations were loaded into our Ontology-Based Database (OBD along with other ontology-based phenotype descriptions of mutants from various model organism databases. Phenotypes recorded with this EQ method can be computationally compared based on the hierarchy of terms in the ontologies and the frequency of annotation. We utilized four similarity metrics to compare phenotypes and developed an ontology of homologous and analogous anatomical structures to compare phenotypes between species. Using these tools, we demonstrate that we can identify, through the similarity of the recorded phenotypes, other alleles of the same gene, other members of a signaling pathway, and orthologous genes and pathway members across species. We conclude that EQ-based annotation of phenotypes, in conjunction with a cross-species ontology, and a variety of similarity metrics can identify biologically meaningful similarities between genes by comparing phenotypes alone. This annotation and search method provides a novel and efficient means to identify

  8. The Canadian approach to science-based regulation of the long distance transport of animals

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    Gordon Doonan

    2008-03-01

    Full Text Available Government regulators face numerous challenges when considering economic necessities (real and perceived, societal expectations on how animals should be treated, scientific research into the needs of various animal species and daily transport practices in the 'real world'. Do we regulate to promote economic competitiveness, to appease animal welfare interest groups and satisfy industry lobbying organisations, or to meet the needs of the animals? In Canada, a recipe to blend regulatory intervention with voluntary, industry-derived standards is the approach of choice.

  9. Summary of three-dimensional animation creation based on ethnic culture element

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    Shao Zhaopo

    2016-01-01

    Full Text Available three-dimensional animation is a product combined by technology and art. It is an artistic ex-pression form combining painting, film & television, digital technology, music, and literature. As an audio and visual art, three-dimensional animation has its own unique culture-loading function, technical aesthetic charac-teristics, and requirements for national art expression. This paper aims to find the method to combine digital technology and national art in combination of three-dimensional animation short film creation, and hopes to clear the road for the cultivation of domestic three-dimensional animation quality project.

  10. Dynamic oceanography determines fine scale foraging behavior of Masked Boobies in the Gulf of Mexico.

    Science.gov (United States)

    Poli, Caroline L; Harrison, Autumn-Lynn; Vallarino, Adriana; Gerard, Patrick D; Jodice, Patrick G R

    2017-01-01

    During breeding, foraging marine birds are under biological, geographic, and temporal constraints. These contraints require foraging birds to efficiently process environmental cues derived from physical habitat features that occur at nested spatial scales. Mesoscale oceanography in particular may change rapidly within and between breeding seasons, and findings from well-studied systems that relate oceanography to seabird foraging may transfer poorly to regions with substantially different oceanographic conditions. Our objective was to examine foraging behavior of a pan-tropical seabird, the Masked Booby (Sula dactylatra), in the understudied Caribbean province, a moderately productive region driven by highly dynamic currents and fronts. We tracked 135 individuals with GPS units during May 2013, November 2013, and December 2014 at a regionally important breeding colony in the southern Gulf of Mexico. We measured foraging behavior using characteristics of foraging trips and used area restricted search as a proxy for foraging events. Among individual attributes, nest stage contributed to differences in foraging behavior whereas sex did not. Birds searched for prey at nested hierarchical scales ranging from 200 m-35 km. Large-scale coastal and shelf-slope fronts shifted position between sampling periods and overlapped geographically with overall foraging locations. At small scales (at the prey patch level), the specific relationship between environmental variables and foraging behavior was highly variable among individuals but general patterns emerged. Sea surface height anomaly and velocity of water were the strongest predictors of area restricted search behavior in random forest models, a finding that is consistent with the characterization of the Gulf of Mexico as an energetic system strongly influenced by currents and eddies. Our data may be combined with tracking efforts in the Caribbean province and across tropical regions to advance understanding of seabird

  11. Dynamic oceanography determines fine scale foraging behavior of Masked Boobies in the Gulf of Mexico

    Science.gov (United States)

    Poli, Caroline L.; Harrison, Autumn-Lynn; Vallarino, Adriana; Gerard, Patrick D.; Jodice, Patrick G.R.

    2017-01-01

    During breeding, foraging marine birds are under biological, geographic, and temporal constraints. These contraints require foraging birds to efficiently process environmental cues derived from physical habitat features that occur at nested spatial scales. Mesoscale oceanography in particular may change rapidly within and between breeding seasons, and findings from well-studied systems that relate oceanography to seabird foraging may transfer poorly to regions with substantially different oceanographic conditions. Our objective was to examine foraging behavior of a pan-tropical seabird, the Masked Booby (Sula dactylatra), in the understudied Caribbean province, a moderately productive region driven by highly dynamic currents and fronts. We tracked 135 individuals with GPS units during May 2013, November 2013, and December 2014 at a regionally important breeding colony in the southern Gulf of Mexico. We measured foraging behavior using characteristics of foraging trips and used area restricted search as a proxy for foraging events. Among individual attributes, nest stage contributed to differences in foraging behavior whereas sex did not. Birds searched for prey at nested hierarchical scales ranging from 200 m—35 km. Large-scale coastal and shelf-slope fronts shifted position between sampling periods and overlapped geographically with overall foraging locations. At small scales (at the prey patch level), the specific relationship between environmental variables and foraging behavior was highly variable among individuals but general patterns emerged. Sea surface height anomaly and velocity of water were the strongest predictors of area restricted search behavior in random forest models, a finding that is consistent with the characterization of the Gulf of Mexico as an energetic system strongly influenced by currents and eddies. Our data may be combined with tracking efforts in the Caribbean province and across tropical regions to advance understanding of seabird

  12. Dynamic oceanography determines fine scale foraging behavior of Masked Boobies in the Gulf of Mexico.

    Directory of Open Access Journals (Sweden)

    Caroline L Poli

    Full Text Available During breeding, foragin