WorldWideScience

Sample records for range forage production

  1. Effects of Climate Change on Range Forage Production in the San Francisco Bay Area

    Science.gov (United States)

    Chaplin-Kramer, Rebecca; George, Melvin R.

    2013-01-01

    The San Francisco Bay Area in California, USA is a highly heterogeneous region in climate, topography, and habitats, as well as in its political and economic interests. Successful conservation strategies must consider various current and future competing demands for the land, and should pay special attention to livestock grazing, the dominant non-urban land-use. The main objective of this study was to predict changes in rangeland forage production in response to changes in temperature and precipitation projected by downscaled output from global climate models. Daily temperature and precipitation data generated by four climate models were used as input variables for an existing rangeland forage production model (linear regression) for California’s annual rangelands and projected on 244 12 km x 12 km grid cells for eight Bay Area counties. Climate model projections suggest that forage production in Bay Area rangelands may be enhanced by future conditions in most years, at least in terms of peak standing crop. However, the timing of production is as important as its peak, and altered precipitation patterns could mean delayed germination, resulting in shorter growing seasons and longer periods of inadequate forage quality. An increase in the frequency of extremely dry years also increases the uncertainty of forage availability. These shifts in forage production will affect the economic viability and conservation strategies for rangelands in the San Francisco Bay Area. PMID:23472102

  2. Effects of climate change on range forage production in the San Francisco Bay Area.

    Directory of Open Access Journals (Sweden)

    Rebecca Chaplin-Kramer

    Full Text Available The San Francisco Bay Area in California, USA is a highly heterogeneous region in climate, topography, and habitats, as well as in its political and economic interests. Successful conservation strategies must consider various current and future competing demands for the land, and should pay special attention to livestock grazing, the dominant non-urban land-use. The main objective of this study was to predict changes in rangeland forage production in response to changes in temperature and precipitation projected by downscaled output from global climate models. Daily temperature and precipitation data generated by four climate models were used as input variables for an existing rangeland forage production model (linear regression for California's annual rangelands and projected on 244 12 km x 12 km grid cells for eight Bay Area counties. Climate model projections suggest that forage production in Bay Area rangelands may be enhanced by future conditions in most years, at least in terms of peak standing crop. However, the timing of production is as important as its peak, and altered precipitation patterns could mean delayed germination, resulting in shorter growing seasons and longer periods of inadequate forage quality. An increase in the frequency of extremely dry years also increases the uncertainty of forage availability. These shifts in forage production will affect the economic viability and conservation strategies for rangelands in the San Francisco Bay Area.

  3. Effects of climate change on range forage production in the San Francisco Bay Area.

    Science.gov (United States)

    Chaplin-Kramer, Rebecca; George, Melvin R

    2013-01-01

    The San Francisco Bay Area in California, USA is a highly heterogeneous region in climate, topography, and habitats, as well as in its political and economic interests. Successful conservation strategies must consider various current and future competing demands for the land, and should pay special attention to livestock grazing, the dominant non-urban land-use. The main objective of this study was to predict changes in rangeland forage production in response to changes in temperature and precipitation projected by downscaled output from global climate models. Daily temperature and precipitation data generated by four climate models were used as input variables for an existing rangeland forage production model (linear regression) for California's annual rangelands and projected on 244 12 km x 12 km grid cells for eight Bay Area counties. Climate model projections suggest that forage production in Bay Area rangelands may be enhanced by future conditions in most years, at least in terms of peak standing crop. However, the timing of production is as important as its peak, and altered precipitation patterns could mean delayed germination, resulting in shorter growing seasons and longer periods of inadequate forage quality. An increase in the frequency of extremely dry years also increases the uncertainty of forage availability. These shifts in forage production will affect the economic viability and conservation strategies for rangelands in the San Francisco Bay Area.

  4. 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

  5. Organic forage seed production

    OpenAIRE

    BOELT, B.; Deleuran, L.C.

    2000-01-01

    From January 2004 only organically produced seed can be used in organic farming systems within the EU. Danish seed producers and seed companies are establishing an organic forage seed production in order to supply organic growers within the EU with high quality seed of recognised varieties. This brief paper outlines a project investigating improved cultivation and management techniques to ensure such a supply is met.

  6. 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.

  7. African Journal of Range and Forage Science

    African Journals Online (AJOL)

    The African Journal of Range & Forage Science (previously known as Proceedings of the Grassland Society of Southern Africa and Journal of the Grassland Society of Southern Africa) is the leading rangeland and pastoral journal in Africa, and serves as an important reference for anyone interested in the management and ...

  8. Foraging pattern, colony distribution, and foraging range of the Florida harvester ant, Pogonomyrmex badius

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, J.S. (Savannah River Ecology Laboratory); Gentry, J.B.; Aiken, S.C.

    1981-12-01

    This report describes the foraging pattern of the Florida harvester ant Pogonomyrmex badius in a high-density population of colonies. The foraging pattern has both promoted and been influenced by the colony distribution. Pogonomyrmex badius forages from short trails which extend into a surrounding foraging range. Direction of foraging trails is influenced by the location of a colony's near neighbors. Seasonal nest relocations always occur along a foraging trail, usually the main trail. Foraging ranges are not actively defended, but are used almost exclusively by foragers from a single colony. Foraging ranges will be extended into an area abandoned by neighboring foragers, indicating that forager presence may define each colony's range. Colony distribution has remained essentially the same for several years, despite seasonal nest relocations and addition of new colonies. Establishment of trails and exclusive foraging ranges by each colony minimizes encounters with neighboring foragers and guarantees access to available resources; this pattern also promotes maintenance of the existing colony distribution and partitioning of resources.

  9. Foraging pattern, colony distribution, and foraging range of the Florida harvester ant Pogonomyrmex badius

    Energy Technology Data Exchange (ETDEWEB)

    Harrison, J.S.; Gentry, J.B.

    1981-12-01

    This report describes the foraging pattern of the Florida harvester ant Pogonomyrmex badius in a high-density population of colonies. The foraging pattern has both promoted and been influenced by the colony distribution. Pogonomyrmex badius forages from short trails which extend into a surrounding foraging range. Direction of foraging trails is influenced by the location of a colony's near neighbors. Seasonal nest relocations always occur along a foraging trail, usually the main trail. Foraging ranges are not actively defended, but are used almost exclusively by foragers from a single colony. Foraging ranges will be extended into an area abondoned by neighboring foragers, indicating that forager presence may define each colony's range. Colony distribution has remained essentially the same for several years, despite seasonal nest relocations and addition of new colonies. Establishment of trails and exclusive foraging ranges by each colony minimizes encounters with neighboring foragers and guarantees access to available resources; this pattern also pomotes maintenance of the existing colony distribution and partitioning of resources.

  10. Productive Information Foraging

    Science.gov (United States)

    Furlong, P. Michael; Dille, Michael

    2016-01-01

    This paper presents a new algorithm for autonomous on-line exploration in unknown environments. The objective of the algorithm is to free robot scientists from extensive preliminary site investigation while still being able to collect meaningful data. We simulate a common form of exploration task for an autonomous robot involving sampling the environment at various locations and compare performance with a simpler existing algorithm that is also denied global information. The result of the experiment shows that the new algorithm has a statistically significant improvement in performance with a significant effect size for a range of costs for taking sampling actions.

  11. Editorial Greater international exposure for African range and forage ...

    African Journals Online (AJOL)

    Password, Remember me, or Register. DOWNLOAD FULL TEXT Open Access DOWNLOAD FULL TEXT Subscription or Fee Access. Editorial Greater international exposure for African range and forage science. Susi Vetter. Abstract. Click on the link to view the editorial. African Journal of Range & Forage Science 2009, ...

  12. 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

  13. Perceptual Ranges, Information Gathering, and Foraging Success in Dynamic Landscapes.

    Science.gov (United States)

    Fagan, William F; Gurarie, Eliezer; Bewick, Sharon; Howard, Allison; Cantrell, Robert Stephen; Cosner, Chris

    2017-05-01

    How organisms gather and utilize information about their landscapes is central to understanding land-use patterns and population distributions. When such information originates beyond an individual's immediate vicinity, movement decisions require integrating information out to some perceptual range. Such nonlocal information, whether obtained visually, acoustically, or via chemosensation, provides a field of stimuli that guides movement. Classically, however, models have assumed movement based on purely local information (e.g., chemotaxis, step-selection functions). Here we explore how foragers can exploit nonlocal information to improve their success in dynamic landscapes. Using a continuous time/continuous space model in which we vary both random (diffusive) movement and resource-following (advective) movement, we characterize the optimal perceptual ranges for foragers in dynamic landscapes. Nonlocal information can be highly beneficial, increasing the spatiotemporal concentration of foragers on their resources up to twofold compared with movement based on purely local information. However, nonlocal information is most useful when foragers possess both high advective movement (allowing them to react to transient resources) and low diffusive movement (preventing them from drifting away from resource peaks). Nonlocal information is particularly beneficial in landscapes with sharp (rather than gradual) patch edges and in landscapes with highly transient resources.

  14. Biomass production and forage quality of head-smut disease ...

    African Journals Online (AJOL)

    There were differences (P<0.05) between accessions in forage dry matter production that ranged from 28.8-51.2 metric tonnes ha-1 at KALRO-Muguga and 18.1-26.7 metric tonnes ha-1 at KALROKatumani. The accessions (numbers 16783, 16796, 16806 and 16835) resistant to head-smut disease gave dry matter yields ...

  15. 7 CFR 457.117 - Forage production crop insurance provisions.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 6 2010-01-01 2010-01-01 false Forage production crop insurance provisions. 457.117... production crop insurance provisions. The Forage Production Crop Insurance Provisions for the 2001 and... Forage Production Crop Insurance Provisions If a conflict exists among the policy provisions, the order...

  16. Monitoring Forage Production of California Rangeland Using Remote Sensing Observations

    Science.gov (United States)

    Liu, H.; Jin, Y.; Dahlgren, R. A.; O'Geen, A. T.; Roche, L. M.; Smith, A. M.; Flavell, D.

    2016-12-01

    Pastures and rangeland cover more than 10 million hectares in California's coastal and inland foothill regions, providing feeds to livestock and important ecosystem services. Forage production in California has a large year-to-year variation due to large inter-annual and seasonal variabilities in precipitation and temperature. It also varies spatially due to the variability in climate and soils. Our goal is to develop a robust and cost-effective tool to map the near-real-time and historical forage productivity in California using remote sensing observations from Landsat and MODIS satellites. We used a Monteith's eco-physiological plant growth theory: the aboveground net primary production (ANPP) is determined by (i) the absorbed photosynthetically active radiation (APAR) and the (ii) light use efficiency (LUE): ANPP = APAR * LUEmax * f(T) * f(SM), where LUEmax is the maximum LUE, and f(T) and f(SM) are the temperature and soil moisture constrains on LUE. APAR was estimated with Landsat and MODIS vegetation index (VI), and LUE was calibrated with a statewide point dataset of peak forage production measurements at 75 annual rangeland sites. A non-linear optimization was performed to derive maximum LUE and the parameters for temperature and soil moisture regulation on LUE by minimizing the differences between the estimated and measured ANPP. Our results showed the satellite-derived annual forage production estimates correlated well withcontemporaneous in-situ forage measurements and captured both the spatial and temporal productivity patterns of forage productivity well. This remote sensing algorithm can be further improved as new field measurements become available. This tool will have a great importance in maintaining a sustainable range industry by providing key knowledge for ranchers and the stakeholders to make managerial decisions.

  17. Intercropping of Cereals and Legumes for Forage Production

    Directory of Open Access Journals (Sweden)

    Hamdollah ESKANDARI

    2009-12-01

    Full Text Available Cereals are high important in feeding ruminant animals for their high dry matter production and low cost. However, cereals forage is poor in protein content which shows their low quality and nutritive value. Regarding to high feed costs of protein supplementations, legumes can be used in livestock nutrition for their high protein content and, thus, providing cost saving. Since legumes have low dry matter yield, acceptable forage yield and quality can obtained from intercropping of cereals and legumes compared with their sole crops. In this paper, forage quality indicators and different factors affecting forage quality are discussed. Forage production and quality of different cereals-legumes intercropping are also reviewed, where; different legumes had different effect on forage quality when intercropped with specific cereal. Regarding to forage quality and quantity, different cereals also led to different production of forage. A number of factors which must be noticified in selecting cereal-legume intercropping compositions, especially for forage production, were considered.

  18. Refinement for a model describing forage production, animal ...

    African Journals Online (AJOL)

    An existing model describing the influence of Acacia karoo density on forage production, animal production and profitablility is reviewed and amended to introduce recent research results. The refined model predicts that maximum forage production can be attained at 1 220 tree equivalents (TE) per ha, maximum livemass ...

  19. Methane Production of Different Forages in Ruminal Fermentation

    Directory of Open Access Journals (Sweden)

    S. J. Meale

    2012-01-01

    Full Text Available An in vitro rumen batch culture study was completed to compare effects of common grasses, leguminous shrubs and non-leguminous shrubs used for livestock grazing in Australia and Ghana on CH4 production and fermentation characteristics. Grass species included Andropodon gayanus, Brachiaria ruziziensis and Pennisetum purpureum. Leguminous shrub species included Cajanus cajan, Cratylia argentea, Gliricidia sepium, Leucaena leucocephala and Stylosanthes guianensis and non-leguminous shrub species included Annona senegalensis, Moringa oleifera, Securinega virosa and Vitellaria paradoxa. Leaves were harvested, dried at 55°C and ground through a 1 mm screen. Serum bottles containing 500 mg of forage, modified McDougall’s buffer and rumen fluid were incubated under anaerobic conditions at 39°C for 24 h. Samples of each forage type were removed after 0, 2, 6, 12 and 24 h of incubation for determination of cumulative gas production. Methane production, ammonia concentration and proportions of VFA were measured at 24 h. Concentration of aNDF (g/kg DM ranged from 671 to 713 (grasses, 377 to 590 (leguminous shrubs and 288 to 517 (non-leguminous shrubs. After 24 h of in vitro incubation, cumulative gas, CH4 production, ammonia concentration, proportion of propionate in VFA and IVDMD differed (p<0.05 within each forage type. B. ruziziensis and G. sepium produced the highest cumulative gas, IVDMD, total VFA, proportion of propionate in VFA and the lowest A:P ratios within their forage types. Consequently, these two species produced moderate CH4 emissions without compromising digestion. Grazing of these two species may be a strategy to reduce CH4 emissions however further assessment in in vivo trials and at different stages of maturity is recommended.

  20. 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 ...

  1. Winter range drift in the George River Caribou Herd: a response to summer forage limitation?

    Directory of Open Access Journals (Sweden)

    Isabelle Schmelzer

    2003-04-01

    Full Text Available Space use by the George River caribou herd (GRCH changes in correspondence with migration patterns. The traditional range of this herd encompasses an area of approximately 900 000 km2. Range use is seasonal and includes travel to traditional calving grounds. Winter range use however, is more variable. The GRCH has grown rapidly from 5000 animals in 1954 to approximately 775 000 in 1993. Beginning in the mid 1980s, the calving and summer range habitats of the GRCH have deteriorated, resulting in a decline in physical condition and subsequent poor calf survival and low pregnancy rates. We assessed the importance of the winter range as a food source compensating for poor summer range quality through an evaluation of winter range drift and use intensity. We hypothesized that if winter ranges provide a compensatory source of forage, then George River caribou should avoid sites heavily used during the previous winter at a population level. Winter ranges for the GRCH were calculated using 4300 caribou locations obtained 1986-2000. We found that in spite of a doubling in net range area, the size of annual winter ranges did not increase, indicating the occurrence of range drift. Further, George River caribou exhibited avoidance of wintering areas at several spatial scales. Avoidance occurred across a use threshold, where the degree of use (or density during the previous winter determined the level of avoidance during the subsequent winter. As the spatial scale decreased, the degree of avoidance increased. Caribou significantly avoided areas used the previous winter at spatial scales below and including 245 km2 (corresponding to a 75% use distribution. Results suggest winter foraging allows caribou suspend the effects of density-dependent summer forage limitation on herd productivity. As such, analysis of GRCH population trends should be considered in light of both summer and winter range resources.

  2. Model of high-productive varieties in forage pea

    Directory of Open Access Journals (Sweden)

    Valentin Kosev

    2015-06-01

    Full Text Available A linear equation of regression was used for establishment of the influence of quantitative characteristics on the grain productivity in forage pea and for development of a model for breeding work. The model for pea plant with high productivity was characterized by average height of 60–70 cm, 8–10 formed pods, 30–40 seeds per plant and 160–260 g in regard to 1000-seed weight. The obtained results showed that the greatest effect on grain productivity had the seed number per plant, first pod height and 1000-seed weight. Kristal variety had high ecological plasticity and could be considered as close to an ideal type, suitable for growing under wide range of environments. Pleven 4 and Rezonator were determined as high-productive varieties and with low stability, Kerpo and Pikardi - as low-productive but stable varieties. Druzba was identified as unstable and low-productive variety.

  3. Methane Production of Different Forages in In vitro Ruminal Fermentation.

    Science.gov (United States)

    Meale, S J; Chaves, A V; Baah, J; McAllister, T A

    2012-01-01

    An in vitro rumen batch culture study was completed to compare effects of common grasses, leguminous shrubs and non-leguminous shrubs used for livestock grazing in Australia and Ghana on CH4 production and fermentation characteristics. Grass species included Andropodon gayanus, Brachiaria ruziziensis and Pennisetum purpureum. Leguminous shrub species included Cajanus cajan, Cratylia argentea, Gliricidia sepium, Leucaena leucocephala and Stylosanthes guianensis and non-leguminous shrub species included Annona senegalensis, Moringa oleifera, Securinega virosa and Vitellaria paradoxa. Leaves were harvested, dried at 55°C and ground through a 1 mm screen. Serum bottles containing 500 mg of forage, modified McDougall's buffer and rumen fluid were incubated under anaerobic conditions at 39°C for 24 h. Samples of each forage type were removed after 0, 2, 6, 12 and 24 h of incubation for determination of cumulative gas production. Methane production, ammonia concentration and proportions of VFA were measured at 24 h. Concentration of aNDF (g/kg DM) ranged from 671 to 713 (grasses), 377 to 590 (leguminous shrubs) and 288 to 517 (non-leguminous shrubs). After 24 h of in vitro incubation, cumulative gas, CH4 production, ammonia concentration, proportion of propionate in VFA and IVDMD differed (pforage type. B. ruziziensis and G. sepium produced the highest cumulative gas, IVDMD, total VFA, proportion of propionate in VFA and the lowest A:P ratios within their forage types. Consequently, these two species produced moderate CH4 emissions without compromising digestion. Grazing of these two species may be a strategy to reduce CH4 emissions however further assessment in in vivo trials and at different stages of maturity is recommended.

  4. 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

  5. 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.

  6. Intercropping of Cereals and Legumes for Forage Production

    OpenAIRE

    Hamdollah ESKANDARI; Ghanbari, Ahmad; Abdollah JAVANMARD

    2009-01-01

    Cereals are high important in feeding ruminant animals for their high dry matter production and low cost. However, cereals forage is poor in protein content which shows their low quality and nutritive value. Regarding to high feed costs of protein supplementations, legumes can be used in livestock nutrition for their high protein content and, thus, providing cost saving. Since legumes have low dry matter yield, acceptable forage yield and quality can obtained from intercropping of cereals and...

  7. 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

    2017-10-12

    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.

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

    African Journals Online (AJOL)

    Three strategies for the integration of improved forages to improve the standard of living, especially of smallholders, are outlined, mindful of various farmer and farming conditions and associated community specific socio-economic circumstances which tend to preclude their use. The specific values of a range of herbaceous ...

  9. Seasonal dry matter production, botanical composition and forage ...

    African Journals Online (AJOL)

    The seasonal growth and low forage quality of kikuyu restrict milk production. The aim of this study was to determine the yield and nutritional value of irrigated kikuyu over-sown with perennial, Italian or Westerwolds ryegrass grazed by dairy cows. The three pasture systems reached optimum growth during different months ...

  10. Determination of the best forage production period for cattle farming ...

    African Journals Online (AJOL)

    A study was carried out to determine the best forage production period for cattle farming in the Adamawa (Cameroon). Data were collected on-farm using diachronic observations of cattle herd and pasture for 24 months. These data, analysed with descriptive and Duncan statistics, permitted to show that the period from May ...

  11. Variations in plant forage quality in the range of the Porcupine caribou herd

    Directory of Open Access Journals (Sweden)

    Jill Johnstone

    2002-06-01

    Full Text Available Understanding potential impacts of vegetation change on caribou energetics requires information on variations in forage quality among different plant types and over time. We synthesized data on forage quality (nitrogen, neutral detergent fiber and dry matter digestibility for 10 plant growth forms from existing scientific literature and from field research in the Arctic National Wildlife Refuge, Alaska. These data describe forage quality of plant species in habitats found within the summer and winter range of the Porcupine caribou herd in northwestern Canada and northern Alaska, U.S.A. We compared mean levels of summer forage quality among growth forms and, where possible, estimated seasonal changes in forage quality. Preferred forage groups (deciduous shrubs, forbs, and cottongrass flowers had higher nitrogen and digestibility, and lower fiber content, than other growth forms. Nitrogen concentration in green biomass peaked at the onset of the growing season in forbs and deciduous shrubs, whereas graminoids reached peak nitrogen concentrations approximately 15-30 days after growth initiation. In vitro dry matter digestibility (IVDMD and concentration of neutral detergent fiber (NDF of green biomass differed among growth forms, but did not show strong seasonal changes. IVDMD and NDF concentrations were correlated with nitrogen concentrations in studies that had paired sampling.

  12. Why multicamp layouts? | BR | African Journal of Range and Forage ...

    African Journals Online (AJOL)

    Although it has become standard practice in Southern Africa to recommend grazing systems based on a maximum of five camps, there are indications that the use of multicamp layouts, employing a greater number of camps per herd, may increase the efficiency of animal production from natural veld. The basic advantage of ...

  13. Foraging and ranging behavior during a fallback episode: Hylobates albibarbis and Pongo pygmaeus wurmbii compared.

    Science.gov (United States)

    Vogel, Erin R; Haag, Livia; Mitra-Setia, Tatang; van Schaik, Carel P; Dominy, Nathaniel J

    2009-12-01

    Periodic episodes of food scarcity may highlight the adaptive value of certain anatomical traits, particularly those that facilitate the acquisition and digestion of exigent fallback foods. To better understand the selective pressures that favored the distinctive dental and locomotor morphologies of gibbons and orangutans, we examined the foraging and ranging behavior of sympatric Hylobates albibarbis and Pongo pygmaeus wurmbii during an episode of low fruit availability at Tuanan, Kalimantan Tengah, Indonesia. We found that Hylobates ranged 0.5 km day(-1) or 33% farther than did Pongo, but the overall daily ranging of both species did not vary as fruit availability decreased by as much as 50%. Among gibbons, we observed dietary switching to fallback foods; in particular, there was a progressively greater reliance on figs, liana products, and unripe fruit. Orangutans relied heavily on unripe fruit and fracture-resistant bark and pith tissues. Despite these divergent fallback patterns, the stiffness of fruit mesocarp consumed by Hylobates and Pongo did not differ. We discuss canine and molar functional morphology with respect to dietary mechanics. Next, to contextualize these results, we discuss our findings with respect to forest structure. The rain forests of Southeast Asia have been described as having open, discontinuous canopies. Such a structure may inform our understanding of the ranging behavior and distinctive locomotion of apes in the region, namely richochetal brachiation and quadrumanous clambering. Our approach of integrating behavioral ecology with physical measures of food may be a powerful tool for understanding the functional adaptations of primates.

  14. Wolf, Canis lupus, visits to white-tailed deer, Odocoileus virginianus, summer ranges: Optimal foraging?

    Science.gov (United States)

    Demma, D.J.; Mech, L.D.

    2009-01-01

    We tested whether Wolf (Canis lupus) visits to individual female White-tailed Deer (Odocoileus virginianus) summer ranges during 2003 and 2004 in northeastern Minnesota were in accord with optimal-foraging theory. Using GPS collars with 10- to 30-minute location attempts on four Wolves and five female deer, plus eleven VHF-collared female deer in the Wolves' territory, provided new insights into the frequency of Wolf visits to summer ranges of female deer. Wolves made a mean 0.055 visits/day to summer ranges of deer three years and older, significantly more than their 0.032 mean visits/day to ranges of two-year-old deer, which generally produce fewer fawns, and most Wolf visits to ranges of older deer were much longer than those to ranges of younger deer. Because fawns comprise the major part of the Wolf's summer diet, this Wolf behavior accords with optimal-foraging theory.

  15. Forage seeding in rangelands increases production and prevents weed invasion

    Directory of Open Access Journals (Sweden)

    Josh Davy

    2017-07-01

    Full Text Available Increasing forage productivity in the Sierra foothill rangelands would help sustain the livestock industry as land availability shrinks and lease rates rise, but hardly any studies have been done on forage selections. From 2009 to 2014, in one of the first long-term and replicated studies of seeding Northern California's Mediterranean annual rangeland, we compared the cover of 22 diverse forages to determine their establishment and survivability over time. Among the annual herbs, forage brassica (Brassica napus L. and chicory (Cichorium intybus L. proved viable options. Among the annual grasses, soft brome (Bromus hordeaceus and annual ryegrass (Lolium multiflorum performed well. However, these species will likely require frequent reseeding to maintain dominance. Long-term goals of sustained dominant cover (> 3 years are best achieved with perennial grasses. Perennial grasses that persisted with greater than 50% cover were Berber orchardgrass (Dactylis glomerata, Flecha tall fescue (Lolium arundinaceum and several varieties of hardinggrass (Phalaris aquatica L., Perla koleagrass, Holdfast, Advanced AT. In 2014, these successful perennials produced over three times more dry matter (pounds per acre than the unseeded control and also suppressed annual grasses and yellow starthistle (Centaurea solstitialis L. cover.

  16. African Journal of Range and Forage Science - Vol 34, No 3 (2017)

    African Journals Online (AJOL)

    Evaluating oat cultivars for dairy forage production in the central Kenyan highlands · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Solomon W Mwendia, Brigitte L Maass, David G Njenga, Fridah N Nyakundi, An Maria O Notenbaert, 145-155 ...

  17. Enteric methane production and ruminal fermentation from forage brassica diets fed in continuous culture

    Science.gov (United States)

    Brassicas provide forage for livestock during the late fall when traditional perennial cool-season forages are not productive. However, little research exists on ruminal fermentation and methane(CH4) production of brassicas fed as forage. A continuous culture fermentor system was used to assess nutr...

  18. Prediction of rumen degradability parameters of a wide range of forages and non-forages by NIRS.

    Science.gov (United States)

    Foskolos, A; Calsamiglia, S; Chrenková, M; Weisbjerg, M R; Albanell, E

    2015-07-01

    Kinetics of nutrient degradation in the rumen is an important component of feed evaluation systems for ruminants. The in situ technique is commonly used to obtain such dynamic parameters, but it requires cannulated animals and incubations last several days limiting its application in practice. On the other hand, feed industry relies strongly on NIRS to predict chemical composition of feeds and it has been used to predict nutrient degradability parameters. However, most of these studies were feedstuff specific, predicting degradability parameters of a particular feedstuff or category of feedstuffs, mainly forages or compound feeds and not grains and byproducts. Our objective was to evaluate the potential of NIRS to predict degradability parameters and effective degradation utilizing a wide range of feedstuffs commonly used in ruminant nutrition. A database of 809 feedstuffs was created. Feedstuffs were grouped as forages (FF; n=256), non-forages (NF; n=539) and of animal origin (n=14). In situ degradability data for dry matter (DM; n=665), CP (n=682) and NDF (n=100) were collected. Degradability was described in terms of washable fraction (a), slowly degradable fraction (b) and its rate of degradation (c). All samples were scanned from 1100 to 2500 nm using an NIRSystems 5000 scanning in reflectance mode. Calibrations were developed for all samples (ALL), FF and NF. Equations were validated with an external validation set of 20% of total samples. NIRS equations to predict the effective degradability and fractions a and b of DM, CP and NDF could be evaluated from being adequate for screening (r(2)>0.77; ratio of performance to deviation (RPD)=2.0 to 2.9) to suitable for quantitative purposes (r(2)>0.84; RPD=3.1 to 4.7), and some predictions were improved by group separation reducing the standard error of prediction. Similarly, the rate of degradation of CP (CP(c)) and DM (DM(c)) was predicted for screening purposes (RPD⩾2 and 2.5 for CP(c) and DM(c), respectively

  19. Assessing the Effects of Grassland Management on Forage Production and Environmental Quality to Identify Paths to Ecological Intensification in Mountain Grasslands.

    Science.gov (United States)

    Loucougaray, Grégory; Dobremez, Laurent; Gos, Pierre; Pauthenet, Yves; Nettier, Baptiste; Lavorel, Sandra

    2015-11-01

    Ecological intensification in grasslands can be regarded as a process for increasing forage production while maintaining high levels of ecosystem functions and biodiversity. In the mountain Vercors massif, where dairy cattle farming is the main component of agriculture, how to achieve forage autonomy at farm level while sustaining environmental quality for tourism and local dairy products has recently stimulated local debate. As specific management is one of the main drivers of ecosystem functioning, we assessed the response of forage production and environmental quality at grassland scale across a wide range of management practices. We aimed to determine which components of management can be harnessed to better match forage production and environmental quality. We sampled the vegetation of 51 grasslands stratified across 13 grassland types. We assessed each grassland for agronomic and environmental properties, measuring forage production, forage quality, and indices based on the abundance of particular plant species such as timing flexibility, apiarian potential, and aromatic plants. Our results revealed an expected trade-off between forage production and environmental quality, notably by stressing the contrasts between sown and permanent grasslands. However, strong within-type variability in both production and environmental quality as well as in flexibility of timing of use suggests possible ways to improve this trade-off at grassland and farm scales. As achieving forage autonomy relies on increasing both forage production and grassland resilience, our results highlight the critical role of the ratio between sown and permanent grasslands as a major path for ecological intensification in mountain grasslands.

  20. Assessing the Effects of Grassland Management on Forage Production and Environmental Quality to Identify Paths to Ecological Intensification in Mountain Grasslands

    Science.gov (United States)

    Loucougaray, Grégory; Dobremez, Laurent; Gos, Pierre; Pauthenet, Yves; Nettier, Baptiste; Lavorel, Sandra

    2015-11-01

    Ecological intensification in grasslands can be regarded as a process for increasing forage production while maintaining high levels of ecosystem functions and biodiversity. In the mountain Vercors massif, where dairy cattle farming is the main component of agriculture, how to achieve forage autonomy at farm level while sustaining environmental quality for tourism and local dairy products has recently stimulated local debate. As specific management is one of the main drivers of ecosystem functioning, we assessed the response of forage production and environmental quality at grassland scale across a wide range of management practices. We aimed to determine which components of management can be harnessed to better match forage production and environmental quality. We sampled the vegetation of 51 grasslands stratified across 13 grassland types. We assessed each grassland for agronomic and environmental properties, measuring forage production, forage quality, and indices based on the abundance of particular plant species such as timing flexibility, apiarian potential, and aromatic plants. Our results revealed an expected trade-off between forage production and environmental quality, notably by stressing the contrasts between sown and permanent grasslands. However, strong within-type variability in both production and environmental quality as well as in flexibility of timing of use suggests possible ways to improve this trade-off at grassland and farm scales. As achieving forage autonomy relies on increasing both forage production and grassland resilience, our results highlight the critical role of the ratio between sown and permanent grasslands as a major path for ecological intensification in mountain grasslands.

  1. Importance of Achromatic Contrast in Short-Range Fruit Foraging of Primates

    Science.gov (United States)

    Hiramatsu, Chihiro; Melin, Amanda D.; Aureli, Filippo; Schaffner, Colleen M.; Vorobyev, Misha; Matsumoto, Yoshifumi; Kawamura, Shoji

    2008-01-01

    Trichromatic primates have a ‘red-green’ chromatic channel in addition to luminance and ‘blue-yellow’ channels. It has been argued that the red-green channel evolved in primates as an adaptation for detecting reddish or yellowish objects, such as ripe fruits, against a background of foliage. However, foraging advantages to trichromatic primates remain unverified by behavioral observation of primates in their natural habitats. New World monkeys (platyrrhines) are an excellent model for this evaluation because of the highly polymorphic nature of their color vision due to allelic variation of the L-M opsin gene on the X chromosome. In this study we carried out field observations of a group of wild, frugivorous black-handed spider monkeys (Ateles geoffroyi frontatus, Gray 1842, Platyrrhini), consisting of both dichromats (n = 12) and trichromats (n = 9) in Santa Rosa National Park, Costa Rica. We determined the color vision types of individuals in this group by genotyping their L-M opsin and measured foraging efficiency of each individual for fruits located at a grasping distance. Contrary to the predicted advantage for trichromats, there was no significant difference between dichromats and trichromats in foraging efficiency and we found that the luminance contrast was the main determinant of the variation of foraging efficiency among red-green, blue-yellow and luminance contrasts. Our results suggest that luminance contrast can serve as an important cue in short-range foraging attempts despite other sensory cues that could be available. Additionally, the advantage of red-green color vision in primates may not be as salient as previously thought and needs to be evaluated in further field observations. PMID:18836576

  2. Importance of achromatic contrast in short-range fruit foraging of primates.

    Directory of Open Access Journals (Sweden)

    Chihiro Hiramatsu

    Full Text Available Trichromatic primates have a 'red-green' chromatic channel in addition to luminance and 'blue-yellow' channels. It has been argued that the red-green channel evolved in primates as an adaptation for detecting reddish or yellowish objects, such as ripe fruits, against a background of foliage. However, foraging advantages to trichromatic primates remain unverified by behavioral observation of primates in their natural habitats. New World monkeys (platyrrhines are an excellent model for this evaluation because of the highly polymorphic nature of their color vision due to allelic variation of the L-M opsin gene on the X chromosome. In this study we carried out field observations of a group of wild, frugivorous black-handed spider monkeys (Ateles geoffroyi frontatus, Gray 1842, Platyrrhini, consisting of both dichromats (n = 12 and trichromats (n = 9 in Santa Rosa National Park, Costa Rica. We determined the color vision types of individuals in this group by genotyping their L-M opsin and measured foraging efficiency of each individual for fruits located at a grasping distance. Contrary to the predicted advantage for trichromats, there was no significant difference between dichromats and trichromats in foraging efficiency and we found that the luminance contrast was the main determinant of the variation of foraging efficiency among red-green, blue-yellow and luminance contrasts. Our results suggest that luminance contrast can serve as an important cue in short-range foraging attempts despite other sensory cues that could be available. Additionally, the advantage of red-green color vision in primates may not be as salient as previously thought and needs to be evaluated in further field observations.

  3. Element patterns in albatrosses and petrels: Influence of trophic position, foraging range, and prey type

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, O.R.J., E-mail: oanderson02@qub.ac.u [School of Biological Sciences, MBC, Queen' s University Belfast, Lisburn Road, Belfast BT9 7BL (United Kingdom); Phillips, R.A. [British Antarctic Survey, Natural Environmental Research Council, High Cross, Madingley Road, Cambridge CB3 0ET (United Kingdom); Shore, R.F. [Centre for Ecology and Hydrology, Lancaster Environment Centre, Bailrigg, Lancaster LA1 4AP (United Kingdom); McGill, R.A.R. [Scottish Universities Environmental Research Centre, Scottish Enterprise Technology Park, East Kilbride G75 0QF (United Kingdom); McDonald, R.A. [Central Science Laboratory, Sand Hutton, York YO41 1LZ (United Kingdom); Bearhop, S. [School of Biological Sciences, MBC, Queen' s University Belfast, Lisburn Road, Belfast BT9 7BL (United Kingdom); Centre for Ecology and Conservation, School of Biosciences, University of Exeter, Cornwall Campus, Penryn TR10 9EZ (United Kingdom)

    2010-01-15

    We investigated the concentrations of 22 essential and non-essential elements among a community of Procellariiformes (and their prey) to identify the extent to which trophic position and foraging range governed element accumulation. Stable isotope analysis (SIA) was used to characterise trophic (delta{sup 15}N) and spatial patterns (delta{sup 13}C) among species. Few consistent patterns were observed in element distributions among species and diet appeared to be highly influential in some instances. Arsenic levels in seabird red blood cells correlated with delta{sup 15}N and delta{sup 13}C, demonstrating the importance of trophic position and foraging range for arsenic distribution. Arsenic concentrations in prey varied significantly across taxa, and in the strength of association with delta{sup 15}N values (trophic level). In most instances, element patterns in Procellariiformes showed the clearest separation among species, indicating that a combination of prey selection and other complex species-specific characteristics (e.g. moult patterns) were generally more important determining factors than trophic level per se. - Trophic position, foraging range, and prey type were found to influence element compositions and concentrations in Procellariiformes from South Georgia.

  4. PRODUCTIVE IMPACT OF THE GREEN FORAGE SUPPLY USAGE AT THE DAIRY FARMS

    Directory of Open Access Journals (Sweden)

    LAVINIA MOISE

    2007-05-01

    Full Text Available This paper presents the importance of the crop structure as a tool to maximize efficiency in the conceiving of the green forage supply scheme in a dairy farm. Several apects are necessary to consider for proper green forage utilization by the cattle, as follows: climatic conditions, proper field operations for each crop, optimal harvest date, and farm technical and economical resources. With a high degree of succulence, green forage and derived products (silage, haylage, present addvantages as compared to hay, having superior indices of nutritive value and palatability. A green forage supply scheme was applied on an area of 188 ha taking into account dairy cattle biological traits. Crop structure was as follows: forage maize, Sudan grass, Italian ryegrass, new lucern and old lucerne, and orchardgrass. Insuring the required superior green forage for the dairy cattle according to forage rations, represents one of the main techniques to maximize milk production and to minimize milk production cost.

  5. MORPHOLOGICAL AND PRODUCTIVE CHARACTERIZATION OF FORAGE CACTUS VARIETIES

    Directory of Open Access Journals (Sweden)

    PHILIPE LIMA DE AMORIM

    2015-01-01

    Full Text Available Cultivars of the genus Nopalea are known in Brazil for being tolerant to cochineal carmine attacks, thus making the cultivation of this genus a promising alternative for mitigating the negative effects of this insect on the production of biomass. With the objectives of characterizing morphologically spineless forage cactus varieties and identify morphological characteristics that may be the focus in spineless forage cactus breeding programs, an experiment was conducted in a completely randomized block design with 11 treatments and four replications. The variety Alagoas showed the highest values of weight, area and volume of cladodes. The varieties Negro Michoacan F7 and V7, Tamazunchale V12 showed the highest values of the cladode area index, the total volume of cladodes and total fresh mass production. The varieties Negro Michoacan V7 and F7 presented the highest water use efficiency and dry mass yield. Cladode volume showed the highest correlation coefficients with the fresh weight of cladodes. Aiming the release of varieties for biomass production, varieties Negro Michoacan F7, V7 and Tamazunchale V12 may substitute the Miúda variety. The number and cladode area index may be used as criteria for selection of superior varieties in breeding programs.

  6. Long-distance pollen flow assessment through evaluation of pollinator foraging range suggests transgene escape distances.

    Science.gov (United States)

    Pasquet, Rémy S; Peltier, Alexis; Hufford, Matthew B; Oudin, Emeline; Saulnier, Jonathan; Paul, Lénaic; Knudsen, Jette T; Herren, Hans R; Gepts, Paul

    2008-09-09

    Foraging range, an important component of bee ecology, is of considerable interest for insect-pollinated plants because it determines the potential for outcrossing among individuals. However, long-distance pollen flow is difficult to assess, especially when the plant also relies on self-pollination. Pollen movement can be estimated indirectly through population genetic data, but complementary data on pollinator flight distances is necessary to validate such estimates. By using radio-tracking of cowpea pollinator return flights, we found that carpenter bees visiting cowpea flowers can forage up to 6 km from their nest. Foraging distances were found to be shorter than the maximum flight range, especially under adverse weather conditions or poor reward levels. From complete flight records in which bees visited wild and domesticated populations, we conclude that bees can mediate gene flow and, in some instances, allow transgene (genetically engineered material) escape over several kilometers. However, most between-flower flights occur within plant patches, while very few occur between plant patches.

  7. Performance and economic analyses of year-round forage systems for forage-fed beef production in the Gulf Coast.

    Science.gov (United States)

    Scaglia, G; Rodriguez, J; Gillespie, J; Bhandari, B; Wang, J J; McMillin, K W

    2014-12-01

    , year-round forage systems are a viable alternative for forage-fed beef production; however, the low gains during summer and forage availability during the transition period when hay is necessary deserve further research to find alternatives to improve productivity during those times of the year.

  8. Determinants of forage adoption and production niches among ...

    African Journals Online (AJOL)

    In contrast, distance to market, farm and household size negatively influenced the adoption of forages. Gender, age, off/non-farm income and number of livestock did not influence adoption of forages. Farm size, agro-ecological zone and type of livestock management system influenced the choice of niches for forage ...

  9. FORAGE YIELD, CHEMICAL COMPOSITION AND IN VITRO GAS PRODUCTION OF YELLOW HYBRID MAIZE GROWN IN MEXICO

    Directory of Open Access Journals (Sweden)

    Lizbeth Esmeralda Roblez Jimenez

    2017-12-01

    Full Text Available Maize is the most important forage in feed cattle, due to its higher energy content, however, it is characterized by its wide range of varieties and the possibility of generating a large quantity of final products. The objective of the present study was to evaluate and compare the forage yield, chemical composition and in vitro gas production as fresh and hay of a local yellow criollo maize and six varieties of yellow hybrid maize (HIT13, CML460, PIONER, COPPER, CDMO80001 and CLO80902. Fresh and dry yield did not show differences between treatments (P>0.05, their chemical composition (g / kg DM showed differences (P ˂ 0.05 for the protein content by various storage methods ranging from 59.87 to 59.61 g kg-1 DM per conservation method, NDF ranged from 591 to 686 g kg-1 DM by variety and by the method ranged from 619 to 639 g kg -1 DM, ADF ranged from 298 to 345 g kg-1 DM by variety and 317 to 340 g kg-1 DM by conservation method; ADL ranged from 58 to 41 g kg-1 DM by variety and 41 to 57 g kg-1 DM by conservation method, in vitro gas production  there were no differences (P>0.05 between varieties and conservation method. It is concluded that according to the results obtained, the varieties studied show the same forage yields in both hay and fresh, chemical composition, and in vitro gas production.

  10. Foraging range movements of the endangered Hawaiian hoary bat, Lasiurus cinereus semotus (Chiroptera: Vespertilionidae)

    Science.gov (United States)

    Bonaccorso, Frank J.; Todd, Christopher M.; Miles, Adam C.; Gorresen, P. Marcos

    2015-01-01

    We documented nightly movements of Hawaiian hoary bats (Lasiurus cinereus semotus) on the island of Hawai’i. Based on data from 28 radiotagged individuals mean foraging range (FR) was 230.7±72.3 ha, core-use area (CUA) was 25.5±6.9 ha (or 11.1% of mean FR), and the mean long axis (LAX) across the FR was 3,390.8±754.3 m. There was almost no overlap in CUAs among 4 adult males having overlapping foraging areas and tracked simultaneously or within a 90-day window of each other. CUAs of subadults partially overlapped with multiple adult males or with one other subadult. High variance in FRs, cores use areas, and LAX across the FR perhaps reflect localized stochastic variables such as weather, habitat, and food resources. Hawaiian hoary bats use moderately large FRs among insectivorous bats studied with comparable methodologies; however, foraging activity indicated by documentation of acoustic feeding buzzes is concentrated within one or a few disjunct areas cumulatively forming the 50% fixed kernel of CUA. The concentration of feeding activity, low values of individual overlap, and agonistic chasing behavior within CUAs all demonstrate a structured use of individual space by Hawaiian hoary bats.

  11. Anosmia impairs homing orientation but not foraging behaviour in free-ranging shearwaters.

    Science.gov (United States)

    Padget, O; Dell'Ariccia, G; Gagliardo, A; González-Solís, J; Guilford, T

    2017-08-29

    Shearwaters deprived of their olfactory sense before being displaced to distant sites have impaired homing ability but it is unknown what the role of olfaction is when birds navigate freely without their sense of smell. Furthermore, treatments used to induce anosmia and to disrupt magneto-reception in displacement experiments might influence non-specific factors not directly related to navigation and, as a consequence, the results of displacement experiments can have multiple interpretations. To address this, we GPS-tracked the free-ranging foraging trips of incubating Scopoli's shearwaters within the Mediterranean Sea. As in previous experiments, shearwaters were either made anosmic with 4% zinc sulphate solution, magnetically impaired by attachment of a strong neodymium magnet or were controls. We found that birds from all three treatments embarked on foraging trips, had indistinguishable at-sea schedules of behaviour and returned to the colony having gained mass. However, we found that in the pelagic return stage of their foraging trips, anosmic birds were not oriented towards the colony though coastal navigation was unaffected. These results support the case for zinc sulphate having a specific effect on the navigational ability of shearwaters and thus the view that seabirds consult an olfactory map to guide them across seascapes.

  12. How a simple adaptive foraging strategy can lead to emergent home ranges and increased food intake

    DEFF Research Database (Denmark)

    Nabe-Nielsen, Jacob; Teilmann, Jonas; Tougaard, Jakob

    2013-01-01

    the optimal balance between alternative movement strategies is therefore selectively advantageous. Recent theory suggests that animals are capable of switching movement mode depend- ing on heterogeneities in the landscape, and that different modes may predominate at different temporal scales. Here we develop...... investigate whether the model is capable of producing emergent home ranges and use pattern-oriented modeling to evaluate whether it can reproduce the large-scale movement patterns observed for porpoises in nature. Finally we investigate whether the model enables animals to forage optimally. We found...

  13. Foraging ranges of insectivorous bats shift relative to changes in mosquito abundance.

    Directory of Open Access Journals (Sweden)

    Leroy Gonsalves

    Full Text Available The need to develop effective management strategies for insectivorous bat populations requires an understanding of factors influencing habitat use. Availability of pest prey, such as mosquitoes is likely to be one such factor. To assess whether this is the case, we radio-tracked Vespadelus vulturnus Thomas (little forest bat, a predator of Aedes vigilax Skuse (saltmarsh mosquito, in saltmarsh and adjacent coastal swamp forest during periods of high and low Ae. vigilax abundance. When mosquito abundance in structurally-open saltmarsh was similar to the more cluttered coastal swamp forest, use of saltmarsh by V. vulturnus was disproportionately greater than its availability, with saltmarsh selected preferentially for foraging. However, at times of low Ae. vigilax abundance in saltmarsh, use of saltmarsh by V. vulturnus was reduced and all habitats were used in proportion to availability in the study area. This is the first radio-tracking study to demonstrate a shift in foraging range by an insectivorous bat species correlated with fluctuations in the distribution and abundance of a particular prey resource. The shift in foraging range by V. vulturnus, corresponding with a spatio-temporal variation in abundance of Ae. vigilax highlights the importance of mosquitoes as a dietary item. Broadscale pest control of Ae. vigilax may have ecological implications for the diet and habitat use of V. vulturnus. An adaptive management approach is proposed, whereby careful monitoring of insectivorous bat populations is recommended before and after any application of broadscale mosquito control measures. We also suggest a precautionary approach is taken such that broadscale control of mosquitoes avoids the lactation period of bats, a time when their energetic demands are greatest and when there is reduced risk of contracting mosquito-borne diseases transmitted by Ae. vigilax.

  14. Quality of foraging material and the effect on hens feed intake, egg production and - quality

    DEFF Research Database (Denmark)

    Steenfeldt, Sanna; Hammershøj, Marianne

    2010-01-01

    In a project with organic egg laying hens, the effect of different kind of foraging material was studied on feed intake, egg-production and -quality. Udgivelsesdato: August......In a project with organic egg laying hens, the effect of different kind of foraging material was studied on feed intake, egg-production and -quality. Udgivelsesdato: August...

  15. Comparing the Foraging Efficiency of Beaked Whales On and Off Naval Ranges

    Science.gov (United States)

    2015-09-30

    gathering and analyzing data on foraging performance and efficiency this project will provide detailed energetics data for modeling approaches...study will, for the first time, provide a means to examine variation in foraging efficiency and energetic costs resulting from sonar disturbance. The...1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Comparing the Foraging Efficiency of Beaked Whales On and

  16. How predictability of feeding patches affects home range and foraging habitat selection in avian social scavengers?

    Directory of Open Access Journals (Sweden)

    Sophie Monsarrat

    Full Text Available Feeding stations are commonly used to sustain conservation programs of scavengers but their impact on behaviour is still debated. They increase the temporal and spatial predictability of food resources while scavengers have supposedly evolved to search for unpredictable resources. In the Grands Causses (France, a reintroduced population of Griffon vultures Gyps fulvus can find carcasses at three types of sites: 1. "light feeding stations", where farmers can drop carcasses at their farm (spatially predictable, 2. "heavy feeding stations", where carcasses from nearby farms are concentrated (spatially and temporally predictable and 3. open grasslands, where resources are randomly distributed (unpredictable. The impact of feeding stations on vulture's foraging behaviour was investigated using 28 GPS-tracked vultures. The average home range size was maximal in spring (1272 ± 752 km(2 and minimal in winter (473 ± 237 km(2 and was highly variable among individuals. Analyses of home range characteristics and feeding habitat selection via compositional analysis showed that feeding stations were always preferred compared to the rest of the habitat where vultures can find unpredictable resources. Feeding stations were particularly used when resources were scarce (summer or when flight conditions were poor (winter, limiting long-ranging movements. However, when flight conditions were optimal, home ranges also encompassed large areas of grassland where vultures could find unpredictable resources, suggesting that vultures did not lose their natural ability to forage on unpredictable resources, even when feeding stations were available. However during seasons when food abundance and flight conditions were not limited, vultures seemed to favour light over heavy feeding stations, probably because of the reduced intraspecific competition and a pattern closer to the natural dispersion of resources in the landscape. Light feeding stations are interesting tools

  17. Unique interrelationships between fiber composition, water-soluble carbohydrates, and in vitro gas production for fall-grown oat forages.

    Science.gov (United States)

    Coblentz, W K; Nellis, S E; Hoffman, P C; Hall, M B; Weimer, P J; Esser, N M; Bertram, M G

    2013-01-01

    Sixty samples of 'ForagePlus' oat were selected from a previous plot study for analysis of in vitro gas production (IVGP) on the basis of 2 factors: (1) high (n=29) or low (n=31) neutral detergent fiber (NDF; 62.7±2.61 and 45.1±3.91%, respectively); and (2) the range of water-soluble carbohydrates (WSC) within the high- and low-NDF groups. For the WSC selection factor, concentrations ranged from 4.7 to 13.4% (mean=7.9±2.06%) and from 3.5 to 19.4% (mean=9.7±4.57%) within high- and low-NDF forages, respectively. Our objectives were to assess the relationships between IVGP and various agronomic or nutritional characteristics for high- and low-NDF fall-oat forages. Cumulative IVGP was fitted to a single-pool nonlinear regression model: Y=MAX × (1 - e ([-)(K)(× (t - lag)])), where Y=cumulative gas produced (mL), MAX=maximum cumulative gas produced with infinite incubation time (mL), K=rate constant, t=incubation time (h), and lag=discrete lag time (h). Generally, cumulative IVGP after 12, 24, 36, or 48h within high-NDF fall-oat forages was negatively correlated with NDF, hemicellulose, lignin, and ash, but positively correlated with WSC, nonfiber carbohydrate (NFC), and total digestible nutrients (TDN). For low-NDF fall-grown oat forages, IVGP was positively correlated with growth stage, canopy height, WSC, NFC, and TDN; negative correlations were observed with ash and crude protein (CP) but not generally with fiber components. These responses were also reflected in multiple regression analysis for high- and low-NDF forages. After 12, 24, or 36h of incubation, cumulative IVGP within high-NDF fall-oat forages was explained by complex regression equations utilizing (lignin:NDF)(2), lignin:NDF, hemicellulose, lignin, and TDN(2) as independent variables (R(2)≥0.43). Within low-NDF fall-grown oat forages, cumulative IVGP at these incubation intervals was explained by positive linear relationships with NFC that also exhibited high coefficients of determination (R(2)

  18. Shifts in North Sea forage fish productivity and potential fisheries yield

    DEFF Research Database (Denmark)

    Worsøe Clausen, Lotte; Rindorf, Anna; van Deurs, Mikael

    2017-01-01

    1. Forage fish populations support large scale fisheries and are key components of marine ecosystems across the world, linking secondary production to higher trophic levels. While climate-induced changes in the North Sea zooplankton community are described and documented in literature...... analysed 40 years of recruitment success and growth proxies to reveal changes in productivity and patterns of synchroneity across stocks (i.e. functional complementarity). The relationship between forage fish production and Calanus finmarchicus (an indicator of climate change) was also analysed. We used...... a population model to demonstrate how observed shifts in productivity affected total forage fish biomass and fisheries yield. 3. The productivity of North Sea forage fish changed around 1993 from a higher average productivity to lower average productivity. During the higher productivity period, stocks...

  19. Fatigue of Range 3 Drill Pipe Fatigue des tiges de forage de gamme 3

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    Lubinski A.

    2006-11-01

    Full Text Available Past work on permissible hole curvature ta avoid drill pipe fatigue was bosed upon the assumption that drill pipe does not contact the wall of the hale between tool joints. In the present paper this assumption is removed, and the pipe may either be in contact or in no contact with the hale, whichever is actually the case. Both mothemotics and results in form of grophs are presented and, discussed. The findings of this palper apply mainly to Range 3 drill pipe, but in the case of 3 I/2 in (88.9 mm drill pipe, application is useful even for Range 2. Usage and field results with Range 3 drill pipe are reported. Les travaux déjà effectués sur la courbure admissible dans les trous de forage (« dag legs » pour éviter la fatigue des tiges de forage sont basés sur l'hypothèse que celles-ci ne rentrent pas en contact avec la paroi entre deux raccords de tige. Dans cet article on écarte une telle hypothèse : la tige peut être ou non en contact avec la paroi. Les équations mathématiques et les résultats sous forme graphique sont présentés et discutés. Ils s'appliquent principalement aux tiges de gamme 3 mais sont aussi utiles à celles de gamme 2 et de diamètre égal à 3 I/2 pouces (88,9 mm. On indique l'utilisation et les résultats sur chantier pour les tiges de gamme 3.

  20. Influence of Policy Making in the Profitability of Forage Production Irrigated with Reclaimed Water

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    María del Pino Palacios-Diaz

    2015-08-01

    Full Text Available The limited availability of water at low prices and the current scheme for specific supply arrangements (SSA/REA, both determined at the political level, explain that the goal of being self-sufficient in terms of forage consumption is currently unattainable in the Canaries. The “PFORCA” Plan aims to counteract this reality and increase their level of self-sufficiency. The financial aid relating to the REA reduces the amount payable for the imported fodder (annual 83,000 t versus local product, which influences the decision making by farmers. According to calculations, performed by reusing the water instead of discharging, Maralfalfa production could be competitive against imports, being financially viable with water prices in a range of 0.20–0.30 €/m3 (prices perfectly acceptable for reclaimed water with low levels of treatment, but fulfilling requirements reuse of Spanish law, RD 1620/2007. The economic contribution of forage crops could represent the creation of 640 new jobs, the enhancement of land currently abandoned, plus an increase in Gross Domestic Product (GDP of the archipelago on more than 23 million € (M€, product of the substitution of imports by local production. Also, it would help to save the REA’s aid (6 M€.

  1. Responses of late-lactation cows to forage substitutes in low-forage diets supplemented with by-products.

    Science.gov (United States)

    Hall, M B; Chase, L E

    2014-05-01

    In response to drought-induced forage shortages along with increased corn and soy prices, this study was conducted to evaluate lactation responses of dairy cows to lower-forage diets supplemented with forage substitutes. By-product feeds were used to completely replace corn grain and soybean feeds. Forty-eight late-lactation cows were assigned to 1 of 4 diets using a randomized complete block design with a 2-wk covariate period followed by a 4-wk experimental period. The covariate diet contained corn grain, soybean meal, and 61% forage. Experimental diets contained chopped wheat straw (WS)/sugar beet pulp at 0/12, 3/9, 6/6, or 9/3 percentages of diet dry matter (DM). Corn silage (20%), alfalfa silage (20%), pelleted corn gluten feed (25.5%), distillers grains (8%), whole cottonseed (5%), cane molasses/whey blend (7%), and vitamin and mineral mix with monensin (2.5%) comprised the rest of diet DM. The WS/sugar beet pulp diets averaged 16.5% crude protein, 35% neutral detergent fiber, and 11% starch (DM basis). Cows consuming the experimental diets maintained a 3.5% fat- and protein-corrected milk production (35.2 kg; standard deviation=5.6 kg) that was numerically similar to that measured in the covariate period (35.3 kg; standard deviation=5.0 kg). Intakes of DM and crude protein declined linearly as WS increased, whereas neutral detergent fiber intake increased linearly. Linear increases in time spent ruminating (from 409 to 502 min/d) and eating (from 156 to 223 min/d) were noted as WS inclusion increased. Yields of milk fat and 3.5% fat-and protein-corrected milk did not change as WS increased, but those of protein and lactose declined linearly. Phosphorous intakes were in excess of recommended levels and decreased linearly with increasing WS inclusion. Nutritional model predictions for multiparous cows were closest to actual performance for the National Research Council 2001 model when a metabolizable protein basis was used; primiparous cow performance was

  2. Genetic diversity within honeybee colonies increases signal production by waggle-dancing foragers

    Science.gov (United States)

    Mattila, Heather R; Burke, Kelly M; Seeley, Thomas D

    2008-01-01

    Recent work has demonstrated considerable benefits of intracolonial genetic diversity for the productivity of honeybee colonies: single-patriline colonies have depressed foraging rates, smaller food stores and slower weight gain relative to multiple-patriline colonies. We explored whether differences in the use of foraging-related communication behaviour (waggle dances and shaking signals) underlie differences in foraging effort of genetically diverse and genetically uniform colonies. We created three pairs of colonies; each pair had one colony headed by a multiply mated queen (inseminated by 15 drones) and one colony headed by a singly mated queen. For each pair, we monitored the production of foraging-related signals over the course of 3 days. Foragers in genetically diverse colonies had substantially more information available to them about food resources than foragers in uniform colonies. On average, in genetically diverse colonies compared with genetically uniform colonies, 36% more waggle dances were identified daily, dancers performed 62% more waggle runs per dance, foragers reported food discoveries that were farther from the nest and 91% more shaking signals were exchanged among workers each morning prior to foraging. Extreme polyandry by honeybee queens enhances the production of worker–worker communication signals that facilitate the swift discovery and exploitation of food resources. PMID:18198143

  3. Production and partial characterization of pectinases from forage ...

    African Journals Online (AJOL)

    PG), pectin lyase (PL) and pectinesterase (PE) produced by Aspergillus niger URM4645 was studied in solid-state fermentation (SSF) using forage palm as the substrate. The effect of variable substrate amount, inoculum concentration and ...

  4. Sexual segregation in juvenile New Zealand sea lion foraging ranges: implications for intraspecific competition, population dynamics and conservation.

    Directory of Open Access Journals (Sweden)

    Elaine S Leung

    Full Text Available Sexual segregation (sex differences in spatial organisation and resource use is observed in a large range of taxa. Investigating causes for sexual segregation is vital for understanding population dynamics and has important conservation implications, as sex differences in foraging ecology may affect vulnerability to area-specific human activities. Although behavioural ecologists have proposed numerous hypotheses for this phenomenon, the underlying causes of sexual segregation are poorly understood. We examined the size-dimorphism and niche divergence hypotheses as potential explanations for sexual segregation in the New Zealand (NZ sea lion (Phocarctos hookeri, a nationally critical, declining species impacted by trawl fisheries. We used satellite telemetry and linear mixed effects models to investigate sex differences in the foraging ranges of juvenile NZ sea lions. Male trip distances and durations were almost twice as long as female trips, with males foraging over the Auckland Island shelf and in further locations than females. Sex was the most important variable in trip distance, maximum distance travelled from study site, foraging cycle duration and percent time at sea whereas mass and age had small effects on these characteristics. Our findings support the predictions of the niche divergence hypothesis, which suggests that sexual segregation acts to decrease intraspecific resource competition. As a consequence of sexual segregation in foraging ranges, female foraging grounds had proportionally double the overlap with fisheries operations than males. This distribution exposes female juvenile NZ sea lions to a greater risk of resource competition and bycatch from fisheries than males, which can result in higher female mortality. Such sex-biased mortality could impact population dynamics, because female population decline can lead to decreased population fecundity. Thus, effective conservation and management strategies must take into account

  5. Behavioral thermal tolerances of free-ranging rattlesnakes (Crotalus oreganus) during the summer foraging season.

    Science.gov (United States)

    Putman, Breanna J; Clark, Rulon W

    2017-04-01

    Increasing temperature due to climate change is one of the greatest challenges for wildlife worldwide. Behavioral data on free-ranging individuals is necessary to determine at what temperatures animals modify activity as this would determine their capacity to continue to move, forage, and mate under altered thermal regimes. In particular, high temperatures could limit available surface activity time and time spent on fitness-related activities. Conversely, performance, such as feeding rate, can increase with temperature potentially having positive fitness effects. Here, we examine how the hunting behaviors of free-ranging Northern Pacific Rattlesnakes (Crotalus oreganus) associate with air temperature and body temperature. We continuously recorded snakes in the field using videography, capturing behaviors rarely considered in past studies such as movements in and out of refuge and strikes on prey. We found that as mean daily air temperature increased, hunting activity and the likelihood of hunting at night decreased, while the number of movements and distance moved per day increased. Snakes typically retreated to refuge before body temperatures reached 31°C. Body temperatures of snakes hunting on the surface were lower compared to temperatures of non-hunting snakes in refuge in the morning, while this relationship was inverted in the afternoon. Snake body size influenced the disparity of these temperatures. Finally, strike initiation and success occurred across a wide range of body temperatures, indicating hunting performance may not be strongly constrained by temperature. These results on the temperatures at which free-ranging rattlesnakes exhibit fitness-related behaviors could be valuable for understanding their vulnerabilities to future climates. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Unique interrelationships between fiber composition, water-soluble carbohydrates, and in vitro gas production for fall-grown oat forages

    Science.gov (United States)

    Recently, several research projects evaluated the potential of fall-grown oat (Avena sativa L.) for use as emergency fall forage to extend the grazing season, or for routine use as an additional forage production option. Sixty samples of ‘ForagePlus’ oat were selected from a previous plot study for ...

  7. Effect of Manure vs. Fertilizer Inputs on Productivity of Forage Crop Models

    Directory of Open Access Journals (Sweden)

    Pasquale Martiniello

    2011-06-01

    Full Text Available Manure produced by livestock activity is a dangerous product capable of causing serious environmental pollution. Agronomic management practices on the use of manure may transform the target from a waste to a resource product. Experiments performed on comparison of manure with standard chemical fertilizers (CF were studied under a double cropping per year regime (alfalfa, model I; Italian ryegrass-corn, model II; barley-seed sorghum, model III; and horse-bean-silage sorghum, model IV. The total amount of manure applied in the annual forage crops of the model II, III and IV was 158, 140 and 80 m3 ha−1, respectively. The manure applied to soil by broadcast and injection procedure provides an amount of nitrogen equal to that supplied by CF. The effect of manure applications on animal feeding production and biochemical soil characteristics was related to the models. The weather condition and manures and CF showed small interaction among treatments. The number of MFU ha−1 of biomass crop gross product produced in autumn and spring sowing models under manure applications was 11,769, 20,525, 11,342, 21,397 in models I through IV, respectively. The reduction of MFU ha−1 under CF ranges from 10.7% to 13.2% those of the manure models. The effect of manure on organic carbon and total nitrogen of topsoil, compared to model I, stressed the parameters as CF whose amount was higher in models II and III than model IV. In term of percentage the organic carbon and total nitrogen of model I and treatment with manure was reduced by about 18.5 and 21.9% in model II and model III and 8.8 and 6.3% in model IV, respectively. Manure management may substitute CF without reducing gross production and sustainability of cropping systems, thus allowing the opportunity to recycle the waste product for animal forage feeding.

  8. Comparison of Raw Dairy Manure Slurry and Anaerobically Digested Slurry as N Sources for Grass Forage Production

    Directory of Open Access Journals (Sweden)

    Olivia E. Saunders

    2012-01-01

    Full Text Available We conducted a 3-year field study to determine how raw dairy slurry and anaerobically digested slurry (dairy slurry and food waste applied via broadcast and subsurface deposition to reed canarygrass (Phalaris arundinacea affected forage biomass, N uptake, apparent nitrogen recovery (ANR, and soil nitrate concentrations relative to urea. Annual N applications ranged from 600 kg N ha−1 in 2009 to 300 g N ha−1 in 2011. Forage yield and N uptake were similar across slurry treatments. Soil nitrate concentrations were greatest at the beginning of the fall leaching season, and did not differ among slurry treatments or application methods. Urea-fertilized plots had the highest soil nitrate concentrations but did not consistently have greatest forage biomass. ANR for the slurry treatments ranged from 35 to 70% when calculations were based on ammonium-N concentration, compared with 31 to 65% for urea. Slurry ANR calculated on a total N basis was lower (15 to 40% due to lower availability of the organic N in the slurries. No consistent differences in soil microbial biomass or other biological indicators were observed. Anaerobically digested slurry supported equal forage production and similar N use efficiency when compared to raw dairy slurry.

  9. Uninformed sacrifice: Evidence against long-range alarm transmission in foraging ants exposed to localized abduction

    Science.gov (United States)

    Tejera, F.; Reyes, A.; Altshuler, E.

    2016-07-01

    It is well established that danger information can be transmitted by ants through relatively small distances, provoking either a state of alarm when they move away from potentially dangerous stimulus, or charge toward it aggressively. There is almost no knowledge if danger information can be transmitted along large distances. In this paper, we abduct leaf cutting ants of the species Atta insularis while they forage in their natural environment at a certain point of the foraging line, so ants make a "U" turn to escape from the danger zone and go back to the nest. Our results strongly suggest that those ants do not transmit "danger information" to other nestmates marching towards the abduction area. The individualistic behavior of the ants returning from the danger zone results in a depression of the foraging activity due to the systematic sacrifice of non-informed individuals.

  10. Foraging ranges of immature African white-backed vultures (Gyps africanus and their use of protected areas in southern Africa.

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    W Louis Phipps

    Full Text Available Vultures in the Gyps genus are declining globally. Multiple threats related to human activity have caused widespread declines of vulture populations in Africa, especially outside protected areas. Addressing such threats requires the estimation of foraging ranges yet such estimates are lacking, even for widespread (but declining species such as the African white-backed vulture (Gyps africanus. We tracked six immature African white-backed vultures in South Africa using GPS-GSM units to study their movement patterns, their use of protected areas and the time they spent in the vicinity of supplementary feeding sites. All individuals foraged widely; their combined foraging ranges extended into six countries in southern Africa (mean (± SE minimum convex polygon area =269,103±197,187 km(2 and three of the vultures travelled more than 900 km from the capture site. All six vultures spent the majority of their tracking periods outside protected areas. South African protected areas were very rarely visited whereas protected areas in northern Botswana and Zimbabwe were used more frequently. Two of the vultures visited supplementary feeding sites regularly, with consequent reduced ranging behaviour, suggesting that individuals could alter their foraging behaviour in response to such sites. We show that immature African white-backed vultures are capable of travelling throughout southern Africa, yet use protected areas to only a limited extent, making them susceptible to the full range of threats in the region. The standard approach of designating protected areas to conserve species is unlikely to ensure the protection of such wide-ranging species against threats in the wider landscape.

  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. Are migrant and resident elk (Cervus elaphus) exposed to similar forage and predation risk on their sympatric winter range?

    Science.gov (United States)

    Robinson, Barry G; Hebblewhite, Mark; Merrill, Evelyn H

    2010-09-01

    Partially migratory populations, where one portion of a population conducts seasonal migrations (migrants) while the other remains on a single range (residents), are common in ungulates. Studies that assess trade-offs between migratory strategies typically compare the amount of predation risk and forage resources migrants and residents are exposed to only while on separate ranges and assume both groups intermix completely while on sympatric ranges. Here we provide one of the first tests of this assumption by comparing the amount of overlap between home ranges of GPS-collared migrant and resident elk and fine-scale exposure to wolf predation risk and forage biomass at telemetry locations on a sympatric winter range in west-central Alberta, Canada. Overlap between migrant and resident home ranges increased throughout the winter, and both groups were generally intermixed and exposed to equal forage biomass. During the day, both migrants and residents avoided predation risk by remaining in areas far from timber with high human activity, which wolves avoided. However, at night wolves moved onto the grasslands close to humans and away from timber. Resident elk were consistently closer to areas of human activity and further from timber than migrants, possibly because of a habituation to humans. As a result, resident elk were exposed to higher night-time predation risk than migrants. Our study does not support the assumption that migrant and resident elk are exposed to equal predation risk on their sympatric range when human presence alters predation risk dynamics and habituation to humans is unequal between migratory strategies.

  13. Relationship between the morphogenesis of Italian ryegrass cv. 'BRS Ponteio' with forage and seed production

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    Ricardo Pereira da Cunha

    2016-01-01

    Full Text Available This study aims to verify, accurate and precisely, the responses of Italian ryegrass 'BRS Ponteio' cultivar to different frequencies of defoliation for forage production and especially for seed production. For this purpose, a randomized block design experiment with four replications was conducted. Four frequencies of defoliation were applied (zero, one, two, and three based on the thermal sum, evaluating the rate of leaf appearance (LAR, phyllochron (P, leaf expansion rate (LER, leaf senescence rate (LSR, stems expansion rate (SER, tillering rate (TR, leaf life span (LL, forage production, proportion of leaf blades, stems plus sheaths, senescent material, and inflorescences, as well as seed production. Second defoliation noticeably altered the morphogenic plant responses, reduced expansion rates and leaf appearance, increased rates of tillering and stems expansion. This phenotypic maintained a high seed production and provided a harvest of forage mass 100% higher than the collected mass in the first cutting. Third defoliation led to an increase of 100% of the harvested forage mass; however, it caused drastic and negative changes in the morphogenic characteristics and seed yielding.

  14. Productivity of Forages in Grassland Merapi Post-Eruption Area, Sleman, Yogyakarta, Indonesia

    Directory of Open Access Journals (Sweden)

    Nafiatul Umami

    2015-05-01

    Full Text Available This research aimed to investigate the productivity and quality of forages (including dry matter, organic matter, crude fiber, crude protein, and extract ether in the area of Kali Kuning and Krasak River. This area was affected by Mount Merapi Eruption on 2010. The data were taken from the area around the river due to the area was found to be firstly revegetated after the eruption. The Forage classified as grass, legume and forbs. The method applied in the research was Line Intercept method which was done by seeing the botanical composition there and was performed at several observation points. The forage was taken as the sample and then calculated its production and proximately analyzed to determine its chemical composition. The results showed that around the river, the widest cover area in 2013 and 2014 was Brachiariabrizantha grasses. The largest dry matter production in 2013 was Pennisetumpurpuphoides as much as 165.57 g m–2, while in 2014 the largest production of DM was Brachiariabrizantha as much as 190.37 g m–2. Frobs with another type of weed also spread in this area. The Quality of forages around Krasak River increased in 2014 due to the addition of organic matter contained in the soil and the minerals weathering from year to year.

  15. Methane and hydrogen sulfide production during co-digestion of forage radish and dairy manure

    Science.gov (United States)

    Forage radish cover crops were investigated as a co-substrate to increase biogas production from dairy manure-based anaerobic digestion. Lab-scale batch digesters (300 mL) were operated under mesophilic conditions during two experiments. In the first experiment, the optimal co-digestion ratio for ...

  16. The analysis of forage quality for organic milk production in Fruska Gora region

    OpenAIRE

    Grdović Svetlana; Savić Mila; Jovanović S.; Popović-Vranješ Anka; Petrujkić B.; Bosančić D.

    2010-01-01

    As a result of the growing demand for organic products, especially organic milk, the livestock organic production has increased. In this paper botanical and chemical composition of forage for organic diary cow production in Fruska Gora region were analysed. In the mixed hay samples, species from the Poaceae family were classified, according to their nutritive value into the first class. Dominant presence of Dactilys glomerata L. and Poa pratensis was revealed. Lucerne hay was predominantly co...

  17. Forage quality declines with rising temperatures, with implications for livestock production and methane emissions

    Science.gov (United States)

    Lee, Mark A.; Davis, Aaron P.; Chagunda, Mizeck G. G.; Manning, Pete

    2017-03-01

    Livestock numbers are increasing to supply the growing demand for meat-rich diets. The sustainability of this trend has been questioned, and future environmental changes, such as climate change, may cause some regions to become less suitable for livestock. Livestock and wild herbivores are strongly dependent on the nutritional chemistry of forage plants. Nutrition is positively linked to weight gains, milk production and reproductive success, and nutrition is also a key determinant of enteric methane production. In this meta-analysis, we assessed the effects of growing conditions on forage quality by compiling published measurements of grass nutritive value and combining these data with climatic, edaphic and management information. We found that forage nutritive value was reduced at higher temperatures and increased by nitrogen fertiliser addition, likely driven by a combination of changes to species identity and changes to physiology and phenology. These relationships were combined with multiple published empirical models to estimate forage- and temperature-driven changes to cattle enteric methane production. This suggested a previously undescribed positive climate change feedback, where elevated temperatures reduce grass nutritive value and correspondingly may increase methane production by 0.9 % with a 1 °C temperature rise and 4.5 % with a 5 °C rise (model average), thus creating an additional climate forcing effect. Future methane production increases are expected to be largest in parts of North America, central and eastern Europe and Asia, with the geographical extent of hotspots increasing under a high emissions scenario. These estimates require refinement and a greater knowledge of the abundance, size, feeding regime and location of cattle, and the representation of heat stress should be included in future modelling work. However, our results indicate that the cultivation of more nutritious forage plants and reduced livestock farming in warming regions

  18. Nutrient foraging strategies are associated with productivity and population growth in forest shrubs.

    Science.gov (United States)

    Caplan, Joshua S; Stone, Bram W G; Faillace, Cara A; Lafond, Jonathan J; Baumgarten, Joni M; Mozdzer, Thomas J; Dighton, John; Meiners, Scott J; Grabosky, Jason C; Ehrenfeld, Joan G

    2017-04-01

    Temperate deciduous forest understoreys are experiencing widespread changes in community composition, concurrent with increases in rates of nitrogen supply. These shifts in plant abundance may be driven by interspecific differences in nutrient foraging (i.e. conservative vs. acquisitive strategies) and, thus, adaptation to contemporary nutrient loading conditions. This study sought to determine if interspecific differences in nutrient foraging could help explain patterns of shrub success and decline in eastern North American forests. Using plants grown in a common garden, fine root traits associated with nutrient foraging were measured for six shrub species. Traits included the mean and skewness of the root diameter distribution, specific root length (SRL), C:N ratio, root tissue density, arbuscular mycorrhizal colonization and foraging precision. Above- and below-ground productivity were also determined for the same plants, and population growth rates were estimated using data from a long-term study of community dynamics. Root traits were compared among species and associations among root traits, measures of productivity and rates of population growth were evaluated. Species fell into groups having thick or thin root forms, which correspond to conservative vs. acquisitive nutrient foraging strategies. Interspecific variation in root morphology and tissue construction correlated with measures of productivity and rates of cover expansion. Of the four species with acquisitive traits, three were introduced species that have become invasive in recent decades, and the fourth was a weedy native. In contrast, the two species with conservative traits were historically dominant shrubs that have declined in abundance in eastern North American forests. In forest understoreys of eastern North America, elevated nutrient availability may impose a filter on species success in addition to above-ground processes such as herbivory and overstorey canopy conditions. Shrubs that have

  19. 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.

  20. Importance and condition of forage crops seed production in agriculture of the Republic of Serbia

    Directory of Open Access Journals (Sweden)

    Đokić Dragoslav

    2013-01-01

    Full Text Available For contemporary and economical livestock production, especially cattle and sheep raising, it is necessary to achieve high production of livestock feed while reducing production costs. Improving the production of perennial grasses and legumes creates a good basis for the development of livestock production in different agro-ecological conditions of Serbia. It also establishes a link between farming and animal husbandry, which is of particular importance for the preservation and higher fertility of arable land and the protection of agro-ecosystems. An important factor for the cheaper production of livestock feed is the possibility to provide sufficient quantities of quality seeds at affordable prices. Production of quality seeds of local varieties of perennial legumes is possible to obtain sufficient amounts of good quality forage. Current situation in forage crop seed production of the Republic of Serbia is unsatisfactory because the seed of perennial grasses are mostly imported. Domestic production of alfalfa, red clover and birdsfoot trefoil met domestic needs only in some years. Seed of imported varieties are often not satisfactory because those varieties are not adapted to our local agro-ecological conditions. The present results provide the basis and direction for further researches that may provide solutions to increase seed yields and which will be widely accepted in practice, which will make the production more cost-effective. Institute for forage crops Kruševac is making a significant contribution to the development of technology of seed productions, especially alfalfa, red clover and perennial grasses. Therefore the role of the Institute is very important and necessary link between production, processing and trading seeds of perennial legumes and grasses in Serbia.

  1. Has eutrophication promoted forage fish production in the Baltic Sea?

    DEFF Research Database (Denmark)

    Eero, Margit; Andersson, Helén C; Almroth-Rosell, Elin

    2016-01-01

    Reducing anthropogenic nutrient inputs is a major policy goal for restoring good environmental status of coastal marine ecosystems. However, it is unclear to what extent reducing nutrients would also lower fish production and fisheries yields. Empirical examples of changes in nutrient loads and c...

  2. The impact of using alternative forages on the nutrient value within slurry and its implications for forage productivity in agricultural systems.

    Directory of Open Access Journals (Sweden)

    Felicity V Crotty

    Full Text Available Alternative forages can be used to provide valuable home-grown feed for ruminant livestock. Utilising these different forages could affect the manure value and the implications of incorporating these forages into farming systems, needs to be better understood. An experiment tested the hypothesis that applying slurries from ruminants, fed ensiled red clover (Trifolium pratense, lucerne (Medicago sativa or kale (Brassica oleracea would improve the yield of hybrid ryegrass (Lolium hybridicum, compared with applying slurries from ruminants fed ensiled hybrid ryegrass, or applying inorganic N alone. Slurries from sheep offered one of four silages were applied to ryegrass plots (at 35 t ha⁻¹ with 100 kg N ha⁻¹ inorganic fertiliser; dry matter (DM yield was compared to plots only receiving ammonium nitrate at rates of 0, 100 and 250 kg N ha⁻¹ year-1. The DM yield of plots treated with 250 kg N, lucerne or red clover slurry was significantly higher than other treatments (Pred clover (81 kg >kale (44 kg >ryegrass (26 kg ha⁻¹ yr⁻¹. These FNE values represent relative efficiencies of 22% (ryegrass, 52% (kale, 47% (red clover and 60% for lucerne slurry, with the ryegrass slurry efficiency being lowest (P = 0.005. Soil magnesium levels in plots treated with legume slurry were higher than other treatments (P<0.001. Overall, slurries from ruminants fed alternative ensiled forages increased soil nutrient status, forage productivity and better N efficiency than slurries from ruminants fed ryegrass silage. The efficiency of fertiliser use is one of the major factors influencing the sustainability of farming systems, these findings highlight the cascade in benefits from feeding ruminants alternative forages, and the need to ensure their value is effectively captured to reduce environmental risks.

  3. Evaluation of germoplasm of Paspalum genus with potential for foraging production

    Directory of Open Access Journals (Sweden)

    Marina Gabriela Berchiol da Silva

    2012-12-01

    Full Text Available This study was carried out in Fazenda Canchim in São Carlos-SP, physical base of Southeast – Embrapa Cattle, aiming to select, based on the agronomic characteristics of productivity of dry matter and quality of the forage, the accesses of suitable gender Paspalum for possessing potentiality of use as foraging plants. Were evaluated for 3 years, with 22 forage grasses, being 19 of Paspalum and three more of control species: Brachiaria decumbens, Andropogon gayanus cv. Baetí and Panicum maximum cv. Tanzania, submitted to two intensification levels: high (fertilizer after each cut and supplemental irrigation and low (only fertilizer of annual replacement without irrigation. The experimental design was a randomized complete block with two replications assigned to a split-plot arrangement. Means were compared using the Scott-Knott test. The studied variables were: dry matter production, in vitro dry matter digestibility and crude protein content. The results indicate that the accesses responded to the intensification level minimizing the negative effect of the seasonal production. Based on the studied variables, the selected accesses were: BRA-011401 (Paspalum glaucescens; BRA-011681 (P. atratum; BRA009661 (P. atratum and BRA-019186 (P. regnellii.

  4. Invited review: Sustainable forage and grain crop production for the US dairy industry.

    Science.gov (United States)

    Martin, N P; Russelle, M P; Powell, J M; Sniffen, C J; Smith, S I; Tricarico, J M; Grant, R J

    2017-12-01

    A resilient US dairy industry will be underpinned by forage and crop production systems that are economically, environmentally, and socially sustainable. Land use for production of perennial and annual forages and grains for dairy cattle must evolve in response to multiple food security and environmental sustainability issues. These include increasing global populations; higher incomes and demand for dairy and other animal products; climate change with associated temperature and moisture changes; necessary reductions in carbon and water footprints; maintenance of soil quality and soil nutrient concerns; and competition for land. Likewise, maintaining producer profitability and utilizing practices accepted by consumers and society generally must also be considered. Predicted changes in climate and water availability will likely challenge current feed and dairy production systems and their national spatial distribution, particularly the western migration of dairy production in the late 20th century. To maintain and stabilize profitability while reducing carbon footprint, particularly reductions in methane emission and enhancements in soil carbon sequestration, dairy production will need to capitalize on genetic and management innovations that enhance forage and grain production and nutritive value. Improved regional and on-farm integration of feed production and manure utilization is needed to reduce environmental nitrogen and phosphorus losses and mitigate greenhouse gas emissions. Resilient and flexible feed production strategies are needed to address each of these challenges and opportunities to ensure profitable feeding of dairy cattle and a sustainable dairy industry. The Authors. Published by the Federation of Animal Science Societies and Elsevier Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).

  5. Climate impacts on agriculture: Implications for forage and rangeland production

    Energy Technology Data Exchange (ETDEWEB)

    Izaurralde, Roberto C.; Thomson, Allison M.; Morgan, Jack; Fay, Philip; Polley, Wayne; Hatfield, Jerry L.

    2011-04-19

    Projections of temperature and precipitation patterns across the United States during the next 50 years anticipate a 1.5 to 2°C warming and a slight increase in precipitation as a result of global climate change. There have been relatively few studies of climate change impacts on pasture and rangeland (grazingland) species compared to those on crop species, despite the economic and ecological importance of the former. Here we review the literature on pastureland and rangeland species to rising CO2 and climate change (temperature, and precipitation) and discuss plant and management factors likely to influence pastureland and rangeland responses to change (e.g., community composition, plant competition, perennial growth habit, seasonal productivity, and management methods). Overall, the response of pasture species to increased [CO2] is consistent with the general response of C3 and C4 type vegetation, although significant exceptions exist. Both pastureland and rangeland species should exhibit an acceleration of metabolism and development due to earlier onset of spring green-up and longer growing seasons. However, in the studies reviewed here, C3 pasture species increased their photosynthetic rates by up to 40% while C4 species exhibited no increase in photosynthesis. In general, it is expected that increases in [CO2] and precipitation would enhance rangeland net primary production (NPP) while increased air temperatures would either increase or decrease NPP. Much of this uncertainty in response is due to uncertain future projections of precipitation, both globally and regionally. For example, if annual precipitation changes little or declines, rangeland plant response to warming temperatures and rising [CO2] may be neutral or may decline due to increased water stress. This review reveals the need for comprehensive studies of climate change impacts on the pasture ecosystem including grazing regimes, mutualistic relationships (e.g., plant roots-nematodes; N

  6. Evolution of protolinguistic abilities as a by-product of learning to forage in structured environments.

    Science.gov (United States)

    Kolodny, Oren; Edelman, Shimon; Lotem, Arnon

    2015-07-22

    The skills required for the learning and use of language are the focus of extensive research, and their evolutionary origins are widely debated. Using agent-based simulations in a range of virtual environments, we demonstrate that challenges of foraging for food can select for cognitive mechanisms supporting complex, hierarchical, sequential learning, the need for which arises in language acquisition. Building on previous work, where we explored the conditions under which reinforcement learning is out-competed by seldom-reinforced continuous learning that constructs a network model of the environment, we now show that realistic features of the foraging environment can select for two critical advances: (i) chunking of meaningful sequences found in the data, leading to representations composed of units that better fit the prevalent statistical patterns in the environment; and (ii) generalization across units based on their contextual similarity. Importantly, these learning processes, which in our framework evolved for making better foraging decisions, had been earlier shown to reproduce a range of findings in language learning in humans. Thus, our results suggest a possible evolutionary trajectory that may have led from basic learning mechanisms to complex hierarchical sequential learning that can support advanced cognitive abilities of the kind needed for language acquisition. © 2015 The Author(s) Published by the Royal Society. All rights reserved.

  7. Effect of cutting intervals and heights in forage productivity of Moringa oleifera.

    Directory of Open Access Journals (Sweden)

    Ramos-Trejo O.

    2015-07-01

    Full Text Available The use of Moringa oleifera as fodder is due to its good nutritional characteristics and high yield of fresh biomass. Eastern Yucatan, Mexico has favorable soil and climatic conditions for its establishment. The aim of this work was to estimate forage productivity of Moringa oleifera in two cutting intervals and three different heights. The experiment was conducted at the Experimental Site of Tizimín fron the National Institute of Forest, Agricultural and lLvestock Researches (INIFAP. The experimental units were placed in a completely randomized design with a 2 x 3 factorial arrangement and four replications. Forage yield was quantified and foliage samples were taken for DM content. Significant differences (p0.05 were found. In conclusion, during the evaluation of Moringa oleifera, it was found that the best performance in this work is obtained when the cuts on the soles are made every 60 days at a height of 40 cm (1.9119 t ha-1 cut-1; however, more agronomic studies of this plant are recommended in the eastern Yucatan, such as: planting density, arrangement, partnerships with other shrub species in the region, rain and dry periods, in order to have a viable and profitable option forage productivity of this plant.

  8. More milk from forage: Milk production, blood metabolites, and forage intake of dairy cows grazing pasture mixtures and spatially adjacent monocultures.

    Science.gov (United States)

    Pembleton, Keith G; Hills, James L; Freeman, Mark J; McLaren, David K; French, Marion; Rawnsley, Richard P

    2016-05-01

    There is interest in the reincorporation of legumes and forbs into pasture-based dairy production systems as a means of increasing milk production through addressing the nutritive value limitations of grass pastures. The experiments reported in this paper were undertaken to evaluate milk production, blood metabolite concentrations, and forage intake levels of cows grazing either pasture mixtures or spatially adjacent monocultures containing perennial ryegrass (Lolium perenne), white clover (Trifolium repens), and plantain (Plantago lanceolata) compared with cows grazing monocultures of perennial ryegrass. Four replicate herds, each containing 4 spring-calving, cross-bred dairy cows, grazed 4 different forage treatments over the periods of early, mid, and late lactation. Forage treatments were perennial ryegrass monoculture (PRG), a mixture of white clover and plantain (CPM), a mixture of perennial ryegrass, white clover, and plantain (RCPM), and spatially adjacent monocultures (SAM) of perennial ryegrass, white clover, and plantain. Milk volume, milk composition, blood fatty acids, blood β-hydroxybutyrate, blood urea N concentrations, live weight change, and estimated forage intake were monitored over a 5-d response period occurring after acclimation to each of the forage treatments. The acclimation period for the early, mid, and late lactation experiments were 13, 13, and 10 d, respectively. Milk yield (volume and milk protein) increased for cows grazing the RCPM and SAM in the early lactation experiment compared with cows grazing the PRG, whereas in the mid lactation experiment, milk fat increased for the cows grazing the RCPM and SAM when compared with the PRG treatments. Improvements in milk production from grazing the RCPM and SAM treatments are attributed to improved nutritive value (particularly lower neutral detergent fiber concentrations) and a potential increase in forage intake. Pasture mixtures or SAM containing plantain and white clover could be a

  9. The value of forage measurement information in rangeland management. [implementation of satellite data in range management

    Science.gov (United States)

    Lietzke, K. R.

    1975-01-01

    An economic model and simulation are developed to estimate the potential social benefit arising from the use of alternative measurement systems in rangeland management. In order to estimate these benefits, it was necessary to model three separate systems: the range environment, the rangeland manager, and the information system which links the two. The rancher's decision-making behavior is modeled according to sound economic principles. Results indicate substantial potential benefits, particularly when used in assisting management of government-operated ranges; possible annual benefits in this area range from $20 to $46 million, depending upon the system capabilities assumed. Possible annual benefit in privately-managed stocker operations range from $2.8 to $49.5 million, depending upon where actual rancher capabilities lie and what system capabilities are assumed.

  10. 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...

  11. The impact of using alternative forages on the nutrient value within slurry and its implications for forage productivity in agricultural systems.

    Science.gov (United States)

    Crotty, Felicity V; Fychan, Rhun; Theobald, Vince J; Sanderson, Ruth; Chadwick, David R; Marley, Christina L

    2014-01-01

    Alternative forages can be used to provide valuable home-grown feed for ruminant livestock. Utilising these different forages could affect the manure value and the implications of incorporating these forages into farming systems, needs to be better understood. An experiment tested the hypothesis that applying slurries from ruminants, fed ensiled red clover (Trifolium pratense), lucerne (Medicago sativa) or kale (Brassica oleracea) would improve the yield of hybrid ryegrass (Lolium hybridicum), compared with applying slurries from ruminants fed ensiled hybrid ryegrass, or applying inorganic N alone. Slurries from sheep offered one of four silages were applied to ryegrass plots (at 35 t ha⁻¹) with 100 kg N ha⁻¹ inorganic fertiliser; dry matter (DM) yield was compared to plots only receiving ammonium nitrate at rates of 0, 100 and 250 kg N ha⁻¹ year-1. The DM yield of plots treated with 250 kg N, lucerne or red clover slurry was significantly higher than other treatments (Pred clover (81 kg) >kale (44 kg) >ryegrass (26 kg ha⁻¹ yr⁻¹). These FNE values represent relative efficiencies of 22% (ryegrass), 52% (kale), 47% (red clover) and 60% for lucerne slurry, with the ryegrass slurry efficiency being lowest (P = 0.005). Soil magnesium levels in plots treated with legume slurry were higher than other treatments (Pforages increased soil nutrient status, forage productivity and better N efficiency than slurries from ruminants fed ryegrass silage. The efficiency of fertiliser use is one of the major factors influencing the sustainability of farming systems, these findings highlight the cascade in benefits from feeding ruminants alternative forages, and the need to ensure their value is effectively captured to reduce environmental risks.

  12. Effect of non-forage roughage replacement on feeding behaviour and milk production in dairy cows

    Directory of Open Access Journals (Sweden)

    Igino Andrighetto

    2011-10-01

    Full Text Available The objective of this study was to determine whether the partial replacement of roughage from forage with non-forage fiber sources, in a total mixed ration (TMR, could reduce feed sorting by dairy cows without modifying behaviour and milk production. Twelve Holstein cows were fed two TMR maize silage based diets in a cross-over experiment. Compared to the control diet (C-diet, experimental diet (E-diet was formulated by replacing 8% neutral detergent fibre (NDF from straw and alfalfa hay with soybean hulls and wheat bran. E-diet had a lower physical effectiveness factor (pef (0.37 vs 0.34; Pvs 14.6%; Pvs. 178 min/d; P<0.05 but showed the same number of meals per day. C-diet fed cows sorted against peNDF in a greater extent (98.3 100.9%; P<0.05. Treatments did not affect cows time budget of general behaviors, with particular regard to ruminating activity. Despite different forage sources in TMR, no significant differences in milk yield and quality were detected.

  13. Stingless bees (Melipona subnitida) adjust brood production rather than foraging activity in response to changes in pollen stores.

    Science.gov (United States)

    Maia-Silva, Camila; Hrncir, Michael; Imperatriz-Fonseca, Vera Lucia; Schorkopf, Dirk Louis P

    2016-10-01

    Highly eusocial bees (honey bees and stingless bees) sustain their colonies through periods of resource scarcity by food stored within the nest. The protein supply necessary for successful brood production is ensured through adjustments of the colonies' pollen foraging according to the availability of this resource in the environment. In honey bees Apis mellifera, in addition, pollen foraging is regulated through the broods' demand for this resource. Here, we investigated the influence of the colony's pollen store level on pollen foraging and brood production in stingless bees (Melipona subnitida). When pollen was added to the nests, colonies increased their brood production and reduced their pollen foraging within 24 h. On the other hand, when pollen reserves were removed, colonies significantly reduced their brood production. In strong contrast to A. mellifera; however, M. subnitida did not significantly increase its pollen foraging activity under poor pollen store conditions. This difference concerning the regulation of pollen foraging may be due to differences regarding the mechanism of brood provisioning. Honey bees progressively feed young larvae and, consequently, require a constant pollen supply. Stingless bees, by contrast, mass-provision their brood cells and temporary absence of pollen storage will not immediately result in substantial brood loss.

  14. Evaluation of Military Range Berm Effectiveness in Protecting Red-cockaded Woodpecker Foraging and Nesting Habitat

    Science.gov (United States)

    2011-04-01

    Ecological Processes Branch (CN-N) of the Installations Division (CN), Construction Engineering Research Laboratory (CERL). The CERL principal...Malone 5 from range toe) and the bermed site (820 m SA-Golf behind berm). 6. It is important to stop bullet ricochets at the target coffins

  15. African Journal of Range and Forage Science - Vol 33, No 3 (2016)

    African Journals Online (AJOL)

    Vachellia karroo leaf meal: a promising non-conventional feed resource for improving goat production in low-input farming systems of Southern Africa · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. E Monday Idamokoro, Patrick J Masika, Voster Muchenje, 141-153.

  16. African Journal of Range and Forage Science - Vol 30, No 3 (2013)

    African Journals Online (AJOL)

    Post-wildfire regeneration of rangeland productivity and functionality – observations across three semi-arid vegetation types in South Africa · EMAIL FULL TEXT EMAIL FULL TEXT · DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. Johannes AD Breedt, Niels Dreber, Klaus Kellner.

  17. Nitrogen partitioning and isotopic fractionation in dairy cows consuming diets based on a range of contrasting forages.

    Science.gov (United States)

    Cheng, L; Kim, E J; Merry, R J; Dewhurst, R J

    2011-04-01

    Nine multiparous Holstein-Friesian cows (initially 97 d in milk), were used in a 3×3 lattice square design experiment with 4-wk periods. All cows received 4 kg/d concentrates and dietary treatments were based on silages offered ad libitum: perennial ryegrass (PRG); timothy (TIM); tall fescue (TF); red clover (RC); red clover/corn silage mixture [40/60 on a dry matter (DM) basis; RCC]; red clover/whole-crop oat silage mixture (40/60 on a DM basis; RCO); or red clover/whole-crop oat silage mixture (25/75 on a DM basis; ORC). The remaining treatments were based on RCO with feed intake restricted to the level of PRG (RCOr) or with a low protein concentrate (50/50 mixture of barley and molassed sugar beet pulp; RCOlp). Experiment objectives were to evaluate diet effects on N partitioning and N isotopic fractionation. Yields of milk and milk protein were consistently high for diets RC, RCC, and RCO and low for the diets based on poorly ensiled grass silages. Restriction of intake (RCOr) and inclusion of a higher proportion of whole-crop oat silage (ORC) and the low-protein concentrate (RCOlp) led to some loss of production. Diet had little effect on milk fat, protein, and lactose concentrations: low concentrations of milk protein and lactose reflect the restricted energy intakes for all treatments. The highest diet digestibilities were measured for RC and PRG, whereas increasing inclusion of the whole-crop oat silage (0, 60, and 75% of forage DM) led to a marked decrease in diet digestibility (0.717, 0.624, and 0.574 g/g, respectively). Urinary excretion of purine derivatives, an indicator for rumen microbial protein synthesis, was significantly higher for RCC than for TIM and TF. Nitrogen intake ranged between 359 and 626 g/d (treatment means). Partitioning of N intake to feces and urine was closely related to N intake, although urinary N losses were less than predicted from N intake for the 60/40 mixtures of cereal silage and red clover silage. The 15N content of milk

  18. Chemical composition, in vitro digestibility and gas production of Brachiaria managed under different forage allowances

    Directory of Open Access Journals (Sweden)

    Andressa F. Ribeiro

    2014-03-01

    Full Text Available The objective of this study was to evaluate the chemical composition, in vitro digestibility, gas production and fermentation kinetics of three Brachiaria cultivars: Brachiaria brizantha cv. Marandu, Brachiaria brizantha cv. Xaraes, and hybrid Brachiaria cv. Mulato, subjected to different levels of forage allowance (4, 7, 10 and 13% of the animal body weight, under rotational grazing cycles. Cultivar Xaraes presented higher contents of neutral detergent fibre, neutral detergent fibre corrected for ash and protein, acid detergent fibre and lignin, and lower production of gases in 96 h in the component leaf blade. There was a decrease of non-fibrous carbohydrates and fraction B2 and an increase in the fraction C of the carbohydrates in the components stem and leaf blade over the grazing cycles in all the cultivars. Cultivar Marandu presented higher digestibility values (in vitro organic matter digestibility and in vitro dry matter digestibility in the components stem and leaf blade. Cultivar Mulato demanded a shorter time of colonisation, according to the calculations of fermentation kinetics. Regardless of the level of forage allowance and of the grazing cycles, the three Brachiaria cultivars were characterised by great fermentation quality due to the relations of the gas production potential and the gas production after 48 and 96 h.

  19. Fatigue of Range 3 Drill Pipe Fatigue des tiges de forage de gamme 3

    OpenAIRE

    Lubinski A.

    2006-01-01

    Past work on permissible hole curvature ta avoid drill pipe fatigue was bosed upon the assumption that drill pipe does not contact the wall of the hale between tool joints. In the present paper this assumption is removed, and the pipe may either be in contact or in no contact with the hale, whichever is actually the case. Both mothemotics and results in form of grophs are presented and, discussed. The findings of this palper apply mainly to Range 3 drill pipe, but in the case of 3 I/2 in (88....

  20. Echolocation signals of free-ranging killer whales (Orcinus orca) and modeling of foraging for chinook salmon (Oncorhynchus tshawytscha)

    Science.gov (United States)

    Au, Whitlow W. L.; Ford, John K. B.; Horne, John K.; Allman, Kelly A. Newman

    2004-02-01

    Fish-eating ``resident''-type killer whales (Orcinus orca) that frequent the coastal waters off northeastern Vancouver Island, Canada have a strong preference for chinook salmon (Oncorhynchus tshawytscha). The whales in this region often forage along steep cliffs that extend into the water, echolocating their prey. Echolocation signals of resident killer whales were measured with a four-hydrophone symmetrical star array and the signals were simultaneously digitized at a sample rate of 500 kHz using a lunch-box PC. A portable VCR recorded the images from an underwater camera located adjacent to the array center. Only signals emanating from close to the beam axis (1185 total) were chosen for a detailed analysis. Killer whales project very broadband echolocation signals (Q equal 0.9 to 1.4) that tend to have bimodal frequency structure. Ninety-seven percent of the signals had center frequencies between 45 and 80 kHz with bandwidths between 35 and 50 kHz. The peak-to-peak source level of the echolocation signals decreased as a function of the one-way transmission loss to the array. Source levels varied between 195 and 224 dB re:1 μPa. Using a model of target strength for chinook salmon, the echo levels from the echolocation signals are estimated for different horizontal ranges between a whale and a salmon. At a horizontal range of 100 m, the echo level should exceed an Orcinus hearing threshold at 50 kHz by over 29 dB and should be greater than sea state 4 noise by at least 9 dB. In moderately heavy rain conditions, the detection range will be reduced substantially and the echo level at a horizontal range of 40 m would be close to the level of the rain noise.

  1. Milk fatty acids profiles and milk production from dairy cows fed different forage quality diets

    Directory of Open Access Journals (Sweden)

    Shuaiwang Liu

    2016-12-01

    Full Text Available Thirty lactating Holstein cows were used to investigate the effects of different forages quality on milk fatty acids (FA profiles and production. The cows were assigned to 3 dietary treatments (n = 10 per treatment in a randomized block design with 3 repeated measures. They were fed the experimental diets for 90 d with 3 days of collection of samples for analysis at about 27 d intervals (samples were collected on days 28, 29, 30, 58, 59, 60, 88, 89 and 90. The treatments were (DM basis: 1 mixed forages diet (MF consisting of 3.7% Chinese wild rye, 26.7% corn silage and 23.4% alfalfa hay; 2 corn stalk diet 1 (CS1 where corn stalk was used to formulate a similar chemical nutrient level to MF; 3 corn stalk diet 2 (CS2 which used corn stalk to formulate a similar forage level to MF for the diet. Dry matter intake and BW were similar between treatments, but daily milk yield, milk fat and protein yield decreased (P < 0.05 in CS1 and CS2 compared with MF, with CS2 being the lowest (P < 0.05. In total FA of milk, the compositions of C18:1c9, C18:3 and unsaturated FA increased (P < 0.05 in CS1 and CS2 compared with MF, and C18:0 and trans-C18:1 were trended to increase (P < 0.10, but C4:0-C16:0 were decreased (P < 0.05. Compared with cows fed CS2, cows receiving CS1 increased the compositions of C4:0 to C12:0 and C18:2 (P < 0.05. The results suggests feeding corn stalk could produce a greater proportion of unsaturated fatty acid (UFA in milk fat without resulting in milk fat depression (MFD in mid lactation cows, but simply increasing the ratio of concentrate in low forages diets is not an effective way to increase milk fat synthesis and milk production.

  2. Factors affecting individual foraging specialization and temporal diet stability across the range of a large “generalist” apex predator

    Science.gov (United States)

    Rosenblatt, Adam E.; Nifong, James C.; Heithaus, Michael R.; Mazzotti, Frank J.; Cherkiss, Michael S.; Jeffery, Brian M.; Elsey, Ruth M.; Decker, Rachel A.; Silliman, Brian R.; Guillette, Louis J.; Lowers, Russell H.; Larson, Justin C.

    2015-01-01

    Individual niche specialization (INS) is increasingly recognized as an important component of ecological and evolutionary dynamics. However, most studies that have investigated INS have focused on the effects of niche width and inter- and intraspecific competition on INS in small-bodied species for short time periods, with less attention paid to INS in large-bodied reptilian predators and the effects of available prey types on INS. We investigated the prevalence, causes, and consequences of INS in foraging behaviors across different populations of American alligators (Alligator mississippiensis), the dominant aquatic apex predator across the southeast US, using stomach contents and stable isotopes. Gut contents revealed that, over the short term, although alligator populations occupied wide ranges of the INS spectrum, general patterns were apparent. Alligator populations inhabiting lakes exhibited lower INS than coastal populations, likely driven by variation in habitat type and available prey types. Stable isotopes revealed that over longer time spans alligators exhibited remarkably consistent use of variable mixtures of carbon pools (e.g., marine and freshwater food webs). We conclude that INS in large-bodied reptilian predator populations is likely affected by variation in available prey types and habitat heterogeneity, and that INS should be incorporated into management strategies to efficiently meet intended goals. Also, ecological models, which typically do not consider behavioral variability, should include INS to increase model realism and applicability.

  3. Whose urban forest? The political ecology of foraging urban nontimber forest products

    Science.gov (United States)

    Patrick T. Hurley; Marla R. Emery; Rebecca McLain; Melissa Poe; Brian Grabbatin; Cari L. Goetcheus

    2015-01-01

    Drawing on case studies of foraging in Philadelphia, Pennsylvania and Mt. Pleasant, South Carolina, we point to foraging landscapes and practices within diverse urban forest spaces. We examine these spaces in relation to U.S. conservation and development processes and the effects of management and governance on species valued by foragers. These case studies reveal the...

  4. Animal production and canopy attributes of Cynodon pasture managed under continuous stocking with wethers at three levels of forage allowance

    Directory of Open Access Journals (Sweden)

    Márcia Vendrúsculo dos Santos

    2012-01-01

    Full Text Available The objective of the present experiment was to evaluate the effect of forage allowance (3, 6 or 9 kg of green leaves dry matter (DM/100 kg of body weight (BW on both animal performance and attributes of Cynodon dactylon var.dactylon canopy managed under continuous stocking by wethers. The study was carried out with 27 Polwarth wethers throughout five 28-day periods, in a completely randomized experiment, which included three paddocks per treatment and three tester animals per paddock. Forage mass varied from 2878 to 6580 kg of DM/ha and was directly related to forage allowance. Leaves proportion (mean of 23% and leaves growth rate (mean of 25 kg of DM/ha/day varied between experimental periods in a similar rate for all treatments. Stocking rate varied from 652 to 2428 kg of LW/ha/day and was higher for the lowest forage allowance treatment. Individual BW gain (mean of 9.7 g/day or gain per area (mean of 406 g/ha/day were only affected by experimental periods. Forage intake was neither affected by treatments nor by periods (mean of 1042 g of DM/day. Cynodon dactylon var. dactylon pasture may be managed under continuous stocking by grazing wethers at forage allowances varying from 3 to 9 kg of green leaves dry matter/100 kg of BW without effects on canopy attributes or animal production.

  5. 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.

  6. Grazing effects on forage production and botanical composition in a Quercus ithaburensis subs. macrolepis silvopastoral system

    Science.gov (United States)

    Pantera, A.; Papanastasis, V. P.

    2009-04-01

    Grazing is considered as a major factor affecting forage production as well as botanical composition of many silvopastoral systems. In order to study these effects, three pairs of grazed and protected plots were established in a Quercus ithaburensis subsp. macrolepis silvopastoral system. The experiment was carried out in western Greece, 15 km west of the city of Agrinion. Data were collected for two continuous years and included the determination of palatable and unpalatable to animals plant species as well as the botanical composition. The results suggest that heavy grazing decreased biomass production approximately threefold. Grazing also affected number of acorns, botanical composition as well as vegetation cover whereas had no effect on natural regeneration in the study period.

  7. Alley cropping of legumes with grasses as forages : Effect of different grass species and row spacing of gliricidia on the growth and biomass production of forages

    Directory of Open Access Journals (Sweden)

    Siti Yuhaeni

    1998-12-01

    Full Text Available A study to evaluate the effect of different grass species and row spacing of gliricidia (Gliricidia sepium on the growth and biomass production of forages in an alley cropping system was conducted in two different agroclimatical zones i.e. Bogor, located at 500 m a .s .l . with an average annual rainfall of 3,112 nun/year and Sukabumi located at 900 m a .s .l . with an average annual rainfall of 1,402 mm/year . Both locations have low N, P, and K content and the soil is classified as acidic. The experimental design used was a split plot design with 3 replicates . The main plots were different grass species i.e. king grass (Pennisetum purpureum x P. typhoides and elephant grass (P. purpureum. The sub plots were the row spacing of gliricidia at 2, 3, 4, 6 m (1 hedgerows and 4 m (2 hedgerows. The results indicated that the growth and biomass production of grasses were significantly affected (P<0 .05 by the treatments in Bogor. The highest biomass productions was obtained from the 2 m row spacing which gave the highest dry matter production of grasses (1 .65 kg/hill and gliricidia (0 .086 kg/tree . In Sukabumi the growth and biomass production of grasses and gliricidia were also significantly affected by the treatments . The highest dry matter production was obtained with 2 m row spacing (dry matter of grasses and gliricidia were 1 .12 kg/hill and 0 .026 kg/tree, respectively . The result further indicated that biomass production of forages increased with the increase in gliricidia population. The alley cropping system wich is suitable for Bogor was the 2 m row spacing of gliricidia intercropped with either king or elephant grass and for Sukabumi 2 and 4 m (2 rows of gliricidia row spacing intercropped with king or elephant grass .

  8. Impact of tropical forage seed development in villages in Thailand and Laos: Research to village farmer production to seed export

    Directory of Open Access Journals (Sweden)

    Michael D. Hare

    2013-12-01

    Full Text Available Seed of 6 forage varieties, Mulato II hybrid brachiaria, Cayman hybrid brachiaria, Mombasa guinea, Tanzania guinea, Ubon stylo and Ubon paspalum, are currently being produced by more than 1000 smallholder farmers in villages in northeast Thailand and northern Laos, under contract to Ubon Forage Seeds, Faculty of Agriculture, Ubon Ratchathani University, Thailand. The seed is mainly exported overseas (95% and the remainder is sold within Thailand. Tropical Seeds LLC, a subsidiary of the Mexican seed company, Grupo Papalotla, employs the seed producing and seed research group, Ubon Forage Seeds, to manage seed production, seed sales and export, and to conduct research on new forage species. This paper discusses in detail how the development in villages of a smallholder farmer seed production program has had positive social and economic outcomes for the village seed growers and enabled farmers in other countries to receive high quality forage seeds. The strong emphasis on seed quality, high purity, high vigor and high germination, has had a large impact on tropical pastures in more than 20 tropical countries in Asia, Africa, the Pacific and Central and South America.

  9. Determinants of spatial behavior of a tropical forest seed predator: The roles of optimal foraging, dietary diversification, and home range defense.

    Science.gov (United States)

    Palminteri, Suzanne; Powell, George V N; Peres, Carlos A

    2016-05-01

    Specialized seed predators in tropical forests may avoid seasonal food scarcity and interspecific feeding competition but may need to diversify their daily diet to limit ingestion of any given toxin. Seed predators may, therefore, adopt foraging strategies that favor dietary diversity and resource monitoring, rather than efficient energy intake, as suggested by optimal foraging theory. We tested whether fine-scale space use by a small-group-living seed predator-the bald-faced saki monkey (Pithecia irrorata)-reflected optimization of short-term foraging efficiency, maximization of daily dietary diversity, and/or responses to the threat of territorial encroachment by neighboring groups. Food patches across home ranges of five adjacent saki groups were widely spread, but areas with higher densities of stems or food species were not allocated greater feeding time. Foraging patterns-specifically, relatively long daily travel paths that bypassed available fruiting trees and relatively short feeding bouts in undepleted food patches-suggest a strategy that maximizes dietary diversification, rather than "optimal" foraging. Travel distance was unrelated to the proportion of seeds in the diet. Moreover, while taxonomically diverse, the daily diets of our study groups were no more species-rich than randomly derived diets based on co-occurring available food species. Sakis preferentially used overlapping areas of their HRs, within which adjacent groups shared many food trees, yet the density of food plants or food species in these areas was no greater than in other HR areas. The high likelihood of depletion by neighboring groups of otherwise enduring food sources may encourage monitoring of peripheral food patches in overlap areas, even if at the expense of immediate energy intake, suggesting that between-group competition is a key driver of fine-scale home range use in sakis. © 2015 Wiley Periodicals, Inc.

  10. Foraging Activity and Trophic Spectrum of Red Ant Pogonomyrmex barbatus Smith, 1858, in Productivity-Contrasted Microenvironments

    Directory of Open Access Journals (Sweden)

    Rafael Guzmán-Mendoza

    2012-01-01

    Full Text Available Foraging strategies can be influenced by many factors such as abundance, availability, and toxicity of the resources. In arid zones, the distribution and productivity of plants also act as additional factors that affect foraging strategies. Twenty colonies of Pogonomyrmex barbatus ants were studied in an arid zone of central Mexico to evaluate the trophic niche breadth in two sites with contrasting productivities in terms of their diversity and amount of resources during two seasons. The results suggest that when the resources are abundant as in the rainy season, the trophic niche breadth is reduced in sites with high productivity and, in the same sites, the trophic niche breadth increases when the resources are limited as in the dry season. In contrast, the trophic niche breadth is similar in both conditions of resource availability (i.e., rainy and dry seasons at sites with low productivity. During the dry season, populations of P. barbatus showed a similar foraging behavior in sites with high and low productivity. Thus, the particular characteristics of a site can significantly affect the foraging strategies of the ants in those environments.

  11. Greenhouse gas emissions from fen soils used for forage production in northern Germany

    Science.gov (United States)

    Poyda, Arne; Reinsch, Thorsten; Kluß, Christof; Loges, Ralf; Taube, Friedhelm

    2016-09-01

    A large share of peatlands in northwestern Germany is drained for agricultural purposes, thereby emitting high amounts of greenhouse gases (GHGs). In order to quantify the climatic impact of fen soils in dairy farming systems of northern Germany, GHG exchange and forage yield were determined on four experimental sites which differed in terms of management and drainage intensity: (a) rewetted and unutilized grassland (UG), (b) intensive and wet grassland (GW), (c) intensive and moist grassland (GM) and (d) arable forage cropping (AR). Net ecosystem exchange (NEE) of CO2 and fluxes of CH4 and N2O were measured using closed manual chambers. CH4 fluxes were significantly affected by groundwater level (GWL) and soil temperature, whereas N2O fluxes showed a significant relation to the amount of nitrate in top soil. Annual balances of all three gases, as well as the global warming potential (GWP), were significantly correlated to mean annual GWL. A 2-year mean GWP, combined from CO2-C eq. of NEE, CH4 and N2O emissions, as well as C input (slurry) and C output (harvest), was 3.8, 11.7, 17.7 and 17.3 Mg CO2-C eq. ha-1 a-1 for sites UG, GW, GM and AR, respectively (standard error (SE) 2.8, 1.2, 1.8, 2.6). Yield-related emissions for the three agricultural sites were 201, 248 and 269 kg CO2-C eq. (GJ net energy lactation; NEL)-1 for sites GW, GM and AR, respectively (SE 17, 9, 19). The carbon footprint of agricultural commodities grown on fen soils depended on long-term drainage intensity rather than type of management, but management and climate strongly influenced interannual on-site variability. However, arable forage production revealed a high uncertainty of yield and therefore was an unsuitable land use option. Lowest yield-related GHG emissions were achieved by a three-cut system of productive grassland swards in combination with a high GWL (long-term mean ≤ 20 cm below the surface).

  12. Milk production response to varying protein supply is independent of forage digestibility in dairy cows

    DEFF Research Database (Denmark)

    Alstrup, Lene; Weisbjerg, Martin Riis; Hymøller, Lone

    2014-01-01

    The aim of this experiment was to examine whether the positive response in milk production to increased crude protein (CP) supply in dairy cows was dependent on the digestibility of the forage. Forty-eight lactating Danish Holstein cows were used in a 4 × 4 Latin square design experiment with 4...... rations: (1) high digestibility and high CP concentration (HdHp), (2) high digestibility and low CP concentration (HdLp), (3) low digestibility and high CP concentration (LdHp), and (4) low digestibility and low CP concentration (LdLp). All rations contained 30% corn silage, 25% grass-clover silage......, and 45% concentrate on a dry matter (DM) basis. Different digestibilities were obtained by replacing a high-digestible grass-clover silage combined with a high-digestible corn silage with a low-digestible grass-clover silage combined with a low-digestible corn silage. Organic matter digestibilities were...

  13. Productivity of duckweed (Lemna minor as alternative forage feed for livestock in different light intensities

    Directory of Open Access Journals (Sweden)

    Uti Nopriani

    2015-12-01

    Full Text Available Duckweed (Lemna minor is a small aquatic plant that grow and float in water and spread extensively. Lemna minor is potential as a source of high quality forage. This study aimed to determine optimal light intensity on Lemna minor to generate maximum productivity. Parameters observed were physical-biological and chemical characteristics of the media (pH value, temperature, cover area, decreased of media volume, BOD, COD, nitrate, nitrite and phosphate, plant growth acceleration (number of shoots, leaf diameter and chlorophyll-a, biomass production, doubling time of cover area and the number of daughters. This study was done based on a completely randomized design with 4 levels of shading. While treatment was: without shading, shading 30%, shading 50% and shading 70% using paranet shade. Each treatment consisted of 4 replications. Result showed that the productivity of Lemna minor included the number of daughters, chlorophyll-a, biomass production, cover area, absorbed phosphate and doubling time the number of daughters reached the highest level without shading treatment (1007,21-2813,57 lux. The decrease of intensity of light, the increase the diameter of leaf. Decrease of media volume was positively correlated to size of cover area. Biomass production influenced by a wide doubling time of cover area and number of daughters.

  14. Corn bran versus corn grain at 2 levels of forage: Intake, apparent digestibility, and production responses by lactating dairy cows.

    Science.gov (United States)

    Arndt, C; Armentano, L E; Hall, M B

    2014-09-01

    The objective of this study was to determine the effect of substituting corn bran (CB) for dried ground corn grain (CG) in the nonforage portion of high-forage (HF) and low-forage (LF) diets. Twelve multiparous and 12 primiparous Holsteins were assigned to 4 diets using six 4× Latin squares with 3-wk periods. Forage was 64 or 38% of the total mixed ration (% of dry matter). On a dry matter basis, the HFCG diet had 20% CG, the LFCG diet had 39% CG, the HFCB diet had 19% CB, and the LFCB diet had 38% CB. Digestible organic matter intake (OMI) and milk energy yield were lower for CB compared with CG within forage level. Digestible OMI was greater (1.9kg/d) for the LFCG compared with the HFCG treatment. When CB replaced forage (LFCB vs. HFCB), digestible OMI was not different but milk energy yield was greater with the LFCB diet. The LFCG diet supported the greatest milk, milk protein, and milk energy yield. Decreased concentration of milk protein and increased concentration of milk urea nitrogen when feeding CB compared with CG suggests that lack of fermentable energy in the CB diets may have limited rumen microbial protein synthesis. Total substitution of CG with CB in the nonforage portion did not support maximum milk production, even when forage was reduced at the same time (HFCG vs. LFCB). Predicted neutral detergent fiber (NDF) digestibility at 1 times maintenance, based on chemical analysis of the individual feeds, was 22 percentage units greater for CB than for the forage mix (68.9 vs. 46.9%). In vitro NDF digestibility (30h) was 19.4 percentage units greater for CB than for the forage mix (68.9 vs. 49.5%). However, in vivo NDF digestibility of the diet when CB replaced forage (HFCB vs. LFCB) was similar (44.1 vs. 44.5%). Similarly, predicted total digestible nutrients at the production level of intake, based on chemical analysis, were greater for the CB treatments and lower for the CG treatments than those observed in vivo. Copyright © 2014 American Dairy

  15. Effect of corn dry distiller grains plus solubles supplementation level on performance and digestion characteristics of steers grazing native range during forage growing season.

    Science.gov (United States)

    Martínez-Pérez, M F; Calderón-Mendoza, D; Islas, A; Encinias, A M; Loya-Olguín, F; Soto-Navarro, S A

    2013-03-01

    Two experiments were conducted to evaluate effects of corn dry distiller grains plus condensed solubles (DDGS) supplementation level on performance digestion characteristics of steers grazing native range during the forage growing season. In the performance study, 72 (206 ± 23.6 kg; 2008) and 60 (230 ± 11.3 kg; 2009) English crossbred steer calves were used in a randomized complete block design replicated over 2 yr. The grazing periods lasted 56 and 58 d and started on August 11 and 18 for 2008 and 2009, respectively. Each year, steers were blocked by BW (light, medium, and heavy), stratified by BW within blocks, and randomly assigned to 1 of 4 grazing groups. Each grazing group (6 steers in 2008 and 5 in 2009) was assigned to a DDGS supplementation levels (0, 0.2, 0.4, and 0.6% BW). Grazing group served as the experimental unit with 12 groups per year receiving 1 of 4 treatments for 2 yr (n = 6). In the metabolism study, 16 English crossbred steers (360 ± 28.9 kg) fitted with ruminal cannulas grazing native range during the summer growing season were used in a completely randomized design to evaluate treatment effects on forage intake and digestion. The experiment was conducted during the first and second weeks of October 2008. Steers were randomly assigned to supplement level (0, 0.2, 0.4, and 0.6% BW; n = 4) and grazed a single native range pasture with supplements offered individually once daily at 0700 h. In the performance study, ADG (0.64, 0.75, 0.80, and 0.86 ± 0.03 kg/d for 0, 0.2, 0.4, and 0.6% BW, respectively) increased linearly (P = 0.01) with increasing DDGS supplementation level. In the metabolism study, forage OM, NDF, CP, and ether extract (EE) intake decreased (P ≤ 0.05) linearly with increasing DDGS supplementation level. Total CP and EE intake increased (P ≤ 0.002) with increasing DDGS supplementation level. Digestibility of OM, NDF, and EE increased (linear; P ≤ 0.008) whereas the soluble CP fraction of forage masticate sample

  16. Social foraging and individual consistency in following behaviour: testing the information centre hypothesis in free-ranging vultures.

    Science.gov (United States)

    Harel, Roi; Spiegel, Orr; Getz, Wayne M; Nathan, Ran

    2017-04-12

    Uncertainties regarding food location and quality are among the greatest challenges faced by foragers and communal roosting may facilitate success through social foraging. The information centre hypothesis (ICH) suggests that uninformed individuals at shared roosts benefit from following informed individuals to previously visited resources. We tested several key prerequisites of the ICH in a social obligate scavenger, the Eurasian griffon vulture (Gyps fulvus), by tracking movements and behaviour of sympatric individuals over extended periods and across relatively large spatial scales, thereby precluding alternative explanations such as local enhancement. In agreement with the ICH, we found that 'informed' individuals returning to previously visited carcasses were followed by 'uninformed' vultures that consequently got access to these resources. When a dyad (two individuals that depart from the same roost within 2 min of each other) included an informed individual, they spent a higher proportion of the flight time close to each other at a shorter distance between them than otherwise. Although all individuals occasionally profited from following others, they differed in their tendencies to be informed or uninformed. This study provides evidence for 'following behaviour' in natural conditions and demonstrates differential roles and information states among foragers within a population. Moreover, demonstrating the possible reliance of vultures on following behaviour emphasizes that individuals in declining populations may suffer from reduced foraging efficiency. © 2017 The Author(s).

  17. Enteric methane production, digestibility and rumen fermentation in dairy cows fed different forages with and without rapeseed fat supplementation

    DEFF Research Database (Denmark)

    Brask, Maike; Lund, Peter; Hellwing, Anne Louise Frydendahl

    2013-01-01

    The purpose of this experiment was to study the effect of forage species (grass or maize) and the maturity stage of grass on enteric methane (CH4) production, nutrient digestibility and rumen fermentation, and to study possible interactions with cracked rapeseed as fat source. Six lactating, rumi...

  18. 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...

  19. Forage management to improve on-farm feed production, nitrogen fluxes and greenhouse gas emissions from dairy systems in a wet temperate region

    DEFF Research Database (Denmark)

    Doltra, J; Villar, A.; Moros, R

    2018-01-01

    for mitigating greenhouse gas emissions (GHG) and enhancing nitrogen (N) fluxes that can support an increase in on-farm forage resources, thus reducing the dependency on external inputs (fertilizers and feed products). A survey conducted in a weighted sample of 40 dairy farms in Cantabria showed four...... and heifers, diet, milk yield and slurry management. The model was applied to simulate carbon (C) and N fluxes at the farm level, and to calculate feed balances, GHG emissions and the N surplus. Farms were simulated under current forage management (baseline) and under scenarios of enhanced forage production....... Milk yield, the balance between forage production and consumption in the animal diet, and between manure generation and application in the field, were used as reference for accepting model simulations. The results from the scenarios indicate that increasing forage productivity, not only reduces...

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

    African Journals Online (AJOL)

    Five forage crops, namely ruzi (Brachiaria ruziziensis), purple guinea (Panicum maximum), atratum (Paspalum atratum), plicatulum (Paspalum plicatulum), and rhodes grass (Chloris gayana), were experimented for their possibility of ethanol and animal feed utilization. All tested forage crops were harvested 45 and 75 days ...

  1. 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.

  2. Chemical composition and in vitro total gas and methane production of forage species from the Mid Rift Valley grasslands of Ethiopia

    NARCIS (Netherlands)

    Bezabih, M.; Pellikaan, W.F.; Tolera, A.; Khan, N.A.; Hendriks, W.H.

    2014-01-01

    There is increasing interest in sustainable land use in the tropics to optimize animal production while also reducing methane (CH4) emissions, but information on nutritive value and CH4-emission potential of tropical forage species is limited. Samples of 24 grasses and five other forages were

  3. FORAGES AND PASTURES SYMPOSIUM: Improving soil health and productivity on grasslands using managed grazing of livestock.

    Science.gov (United States)

    Russell, J R; Bisinger, J J

    2015-06-01

    Beyond grazing, managed grasslands provide ecological services that may offer economic incentives for multifunctional use. Increasing biodiversity of plant communities may maximize net primary production by optimizing utilization of available light, water, and nutrient resources; enhance production stability in response to climatic stress; reduce invasion of exotic species; increase soil OM; reduce nutrient leaching or loading in surface runoff; and provide wildlife habitat. Strategically managed grazing may increase biodiversity of cool-season pastures by creating disturbance in plant communities through herbivory, treading, nutrient cycling, and plant seed dispersal. Soil OM will increase carbon and nutrient sequestration and water-holding capacity of soils and is greater in grazed pastures than nongrazed grasslands or land used for row crop or hay production. However, results of studies evaluating the effects of different grazing management systems on soil OM are limited and inconsistent. Although roots and organic residues of pasture forages create soil macropores that reduce soil compaction, grazing has increased soil bulk density or penetration resistance regardless of stocking rates or systems. But the effects of the duration of grazing and rest periods on soil compaction need further evaluation. Because vegetative cover dissipates the energy of falling raindrops and plant stems and tillers reduce the rate of surface water flow, managing grazing to maintain adequate vegetative cover will minimize the effects of treading on water infiltration in both upland and riparian locations. Through increased diversity of the plant community with alterations of habitat structure, grazing systems can be developed that enhance habitat for wildlife and insect pollinators. Although grazing management may enhance the ecological services provided by grasslands, environmental responses are controlled by variations in climate, soil, landscape position, and plant community

  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. Methanogenic Population and CH4 Production in Swedish Dairy Cows Fed Different Levels of Forage

    Science.gov (United States)

    Schnürer, A.; Arthurson, V.; Bertilsson, J.

    2012-01-01

    Methanogenic community structure, methane production (CH4), and volatile fatty acid (VFA) profiles were investigated in Swedish dairy cows fed a diet with a forage/concentrate ratio of 500/500 or 900/100 g/kg of dry matter (DM) of total DM intake (DMI). The rumen methanogenic population was evaluated using terminal restriction fragment length polymorphism (T-RFLP) analysis, 16S rRNA gene libraries, and quantitative real-time PCR (qRT-PCR). Mean CH4 yields did not differ (P > 0.05) between diets, being 16.9 and 20.2 g/kg DMI for the 500/500 and 900/100 diets, respectively. The T-RFLP analysis revealed that populations differed between individual cows and that each individual population responded differently to the diets. The 16S rRNA gene libraries revealed that Methanobrevibacter spp. dominated for both diets. CH4 production was positively correlated with a dominance of sequences representing T-RFs related to Methanobrevibacter thaueri, Methanobrevibacter millerae, and Methanobrevibacter smithii relative to Methanobrevibacter ruminantium and Methanobrevibacter olleyae. Total numbers of methanogens and total numbers of Methanobacteriales were significantly higher with the 500/500 diet (P cows. PMID:22752163

  6. Soil microbial substrate properties and microbial community responses under irrigated organic and reduced-tillage crop and forage production systems.

    Science.gov (United States)

    Ghimire, Rajan; Norton, Jay B; Stahl, Peter D; Norton, Urszula

    2014-01-01

    Changes in soil microbiotic properties such as microbial biomass and community structure in response to alternative management systems are driven by microbial substrate quality and substrate utilization. We evaluated irrigated crop and forage production in two separate four-year experiments for differences in microbial substrate quality, microbial biomass and community structure, and microbial substrate utilization under conventional, organic, and reduced-tillage management systems. The six different management systems were imposed on fields previously under long-term, intensively tilled maize production. Soils under crop and forage production responded to conversion from monocropping to crop rotation, as well as to the three different management systems, but in different ways. Under crop production, four years of organic management resulted in the highest soil organic C (SOC) and microbial biomass concentrations, while under forage production, reduced-tillage management most effectively increased SOC and microbial biomass. There were significant increases in relative abundance of bacteria, fungi, and protozoa, with two- to 36-fold increases in biomarker phospholipid fatty acids (PLFAs). Under crop production, dissolved organic C (DOC) content was higher under organic management than under reduced-tillage and conventional management. Perennial legume crops and organic soil amendments in the organic crop rotation system apparently favored greater soil microbial substrate availability, as well as more microbial biomass compared with other management systems that had fewer legume crops in rotation and synthetic fertilizer applications. Among the forage production management systems with equivalent crop rotations, reduced-tillage management had higher microbial substrate availability and greater microbial biomass than other management systems. Combined crop rotation, tillage management, soil amendments, and legume crops in rotations considerably influenced soil

  7. 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.

  8. Effect of Cover Crops and Nitrogen Fertilizer on Total Production of Forage Corn and Dry Weight of Weeds

    Directory of Open Access Journals (Sweden)

    R Fakhari

    2014-10-01

    Full Text Available To evaluate the effect of cover crops, split application of nitrogen and control weeds on forage corn and weed biomass a factorial experiment based on randomized complete block design with three replications and three factors was conducted at the Agricultural Research Station of Ardabil (Iran during 2012 crop year. The first factor was cover crops (consisting of winter rye, hairy vetch, berseem clover, with and without weeding as controls. The second factor was two levels of split application of 225 kg.ha-1 urea at two growth stages forage corn: the first level (N1= 1/2 at planting and 1/2 at 8-10 leaf stage, second level (N2= 1/3 at planting, 1/3 at 8-10 leaf and 1/3 one week before tasselling stage. The third factor consisted of two levels of weed control: weeding at 8 leaves and weeding one week before tasselling. Results showed that winter rye, hairy vetch and berseem clover cover crops decreased total weed dry weights up to 87, 82 and 65 % respectively as compared to control (without weeding. Cover crops and nitrogen application time had a significant effect on yield of fresh forage corn and cover crops. Based on the advantages of effective weed control and higher forage production of hairy vetch it can be recommended as proper cover crop.

  9. Productivity and recovery of forage fish under climate change and fishing: North Sea sandeel as a case study

    DEFF Research Database (Denmark)

    Lindegren, Martin; van Deurs, Mikael; MacKenzie, Brian

    2017-01-01

    Forage fish occupy a central position in marine food-webs worldwide by mediating the transfer of energy and organic matter from lower to higher trophic levels. The lesser sandeel (Ammodytes marinus) is one of the ecologically and economically most important forage fish species in the North......-east Atlantic, acting as a key prey for predatory fish and sea birds, as well as supporting a large commercial fishery. In this case study, we investigate the underlying factors affecting recruitment and how these in turn affect productivity of the North Sea sandeel using long-term data and modelling. Our...... results demonstrate how sandeel productivity in the central North Sea (Dogger Bank) depends on a combination of external and internal regulatory factors, including fishing and climate effects, as well as density dependence and food availability of the preferred zooplankton prey (Calanus finmarchicus...

  10. MORPHOLOGICAL CHARACTERISTICS AND FORAGE PRODUCTIVITY OF IRRIGATED CACTUS PEAR UNDER DIFFERENT CUTTING INTENSITIES

    Directory of Open Access Journals (Sweden)

    GUILHERME FERREIRA DA COSTA LIMA

    2016-01-01

    Full Text Available This study evaluated the effect of different cutting intensities and years of harvesting on the morphological characteristics and production of fresh (FMP and dry matter (DMP of cactus pear cv. Gigante (Opuntia ficus-indica Mill under conditions of irrigation, high planting density and fertilization, with 12 months of regrowth. The experimental was completely randomized in a factorial design (3 × 2 with 12 replicates. The treatments were three cutting intensities (preserving the mother cladode (PMC, primary cladodes (PPC, or secondary cladodes (PSC, and two years of harvesting. The soil was classified as Cambisol Haplicum and the irrigation water was classified as C4S1 (EC 5.25 dS.m-1 density of 50,000 plants ha-1. The research evaluated plant height, number of cladodes per plant (NCP, length, width, perimeter and thickness of the cladodes, cladode area (CA, cladode area index (CAI, FMP and DMP. There was no significant interaction between treatments (P > 0.05 for the variables plant height, NCP, CAI and FMP. The variables related to cladode morphology showed a significant interaction (P < 0.05. The treatment PSC resulted in a greater DMP (P < 0.05 with a mean of 27.17 Mg ha-1 yr-1, compared to PPC (18.58 Mg ha-1 yr-1 or PMC (11.78 Mg ha-1 yr-1. The treatment PSC promoted greater NCP and forage productivity at harvest and can be considered as a management practice for the sustainability of cactus pear cv. Gigante under irrigation. The more important morphological characteristics were also influenced by the lower cutting intensities.

  11. Solid/liquid dispersions in drilling and production; Fluides charges en forage et production petroliere

    Energy Technology Data Exchange (ETDEWEB)

    Peysson, Y. [Institut Francais du Petrole (IFP), 92 - Rueil-Malmaison (France)

    2004-07-01

    To reach the new oil and gas fields, the oil industry is developing more and more sophisticated drilling and production schemes. Wells trajectories are now deviated, horizontal, with high extended reach, multi-branched, ultra deep offshore, etc. Extended reach wells are up to 10 km and offshore drilling is close to 3000 m of water depth. In these cases, drilling and production techniques are pushed to the limits. The operating conditions, the properties of the different materials employed must be controlled and operated in a more accurate way. This is the case for solid/liquid dispersions that are common in these operations: drilling, fluids, cements, hydrates dispersions oil and gas phases, sand venue with reservoir fluids, etc. These mixtures present some specific properties that can be at the limit between solid or liquid behaviour. For particular conditions the solid phase can create structures able to support large stresses and in others circumstances the mixture can flow like a viscous paste. Modeling of these characteristics is not easy and needs to use knowledge of different areas: Theology, physico-chemistry, hydrodynamics. thermodynamics, etc. In this revue, different systems used in the drilling and production industry will be discussed. Main properties of these systems and different development conducted by IFP will be addressed. (authors)

  12. Highly productive forage legume stands show no positive biodiversity effect on yield and N2-fixation

    DEFF Research Database (Denmark)

    Dhamala, Nawa Raj; Eriksen, Jørgen; Carlsson, Georg

    2017-01-01

    . Methodology N fixation, dry matter (DM) and nitrogen (N) yields were quantified in a field experiment for red clover (Trifolium pratense L.), white clover (Trifolium repens L.) and lucerne (Medicago sativa L.) pure stands and mixtures using the isotope dilution method. Results All three forage legume species...

  13. Forage quality and reindeer productivity: multiplier effects amplified by climate change

    Science.gov (United States)

    Merben R. Cebrian; Knut Kielland; Greg Finstad

    2008-01-01

    We investigated the effects of experimental manipulations of snowmelt on the flowering phenology and forage chemistry (digestibility and nitrogen concentration) of tussock cottongrass (Eriophonun vaginauoni) on the Seward Peninsula, Alaska. Early snowmelt accelerated reproductive phenology by 11 days, and resulted in higher floral digestibility...

  14. Planting Date Effects on Fall Forage Production of Oat Cultivars in Wisconsin

    Science.gov (United States)

    Previous research has shown that cereal-grains, such as oat (Avena sativa L.), that undergo stem elongation following late-summer establishment will likely exhibit a 2:1 forage DM yield advantage before winter compared to other cereals that remain vegetative until spring. Our objectives for this pro...

  15. Effects of concentrated separator by-product (desugared molasses) on intake, site of digestion, microbial efficiency, and nitrogen balance in ruminants fed forage-based diets.

    Science.gov (United States)

    Lawler-Neville, T L; Shellito, S M; Maddock, T D; Bauer, M L; Lardy, G P; Gilbery, T C; Caton, J S

    2006-08-01

    In Exp. 1, 4 ruminally and duodenally cannulated beef steers (444.0 +/- 9.8 kg) were used in a 4 x 4 Latin square with a 2 x 2 factorial treatment arrangement to evaluate the effects of forage type (alfalfa or corn stover) and concentrated separator byproduct (CSB) supplementation (0 or 10% of dietary DM) on intake, site of digestion, and microbial efficiency. In Exp. 2, 5 wethers (44 +/- 1.5 kg) were used in a 5 x 5 Latin square to evaluate the effects of CSB on intake, digestion, and N balance. Treatments were 0, 10, and 20% CSB (DM basis) mixed with forage; 10% CSB offered separately from the forage; and a urea control, in which urea was added to the forage at equal N compared with the 10% CSB treatment. In Exp. 1, intakes of OM and N (g/kg of BW) were greater (P digestibility; alfalfa with or without CSB was similar (67.4 vs. 69.5), whereas corn stover with CSB was greater than corn stover without CSB (31.9 vs. -23.9%). True ruminal OM digestion was greater (P 0.25) by forage type or CSB supplementation. In Exp. 2, forage and total intake increased (linear; P digestibility compared with 10% CSB fed mixed. Increasing CSB led to an increase (linear; P digestion, and water intake. Nitrogen balance (g and percentage of N intake) increased (linear; P digestion, and increases microbial N production in ruminants fed forage-based diets.

  16. Dynamics of Forage Production in Pasture-woodlands of the Swiss Jura Mountains under Projected Climate Change Scenarios

    Directory of Open Access Journals (Sweden)

    Konstantin S. Gavazov

    2013-03-01

    Full Text Available Silvopastoral systems of the Swiss Jura Mountains serve as a traditional source of forage and timber in the subalpine vegetation belt, but their vulnerability to land use and climate change puts their future sustainability at stake. We coupled experimental and modeling approaches to assess the impact of climate change on the pasture-woodland landscape. We drew conclusions on the resistance potential of wooded pastures with different management intensities by sampling along a canopy cover gradient. This gradient spanned from unwooded pastures associated with intensive farming to densely wooded pastures associated with extensive farming. Transplanted mesocosms of these ecosystems placed at warmer and drier conditions provided experimental evidence that climate change reduced herbaceous biomass production in unwooded pastures but had no effect in sparsely wooded pastures, and even stimulated productivity in densely wooded pastures. Through modeling these results with a spatially explicit model of wooded pastures (WoodPaM modified for the current application, results were extrapolated to the local landscape under two regionalized Intergovernmental Panel on Climate Change scenarios for climate change. This led to the suggestion that within the Jura pasture-woodlands, forage production in the near future (2000-2050 AD would be affected disproportionately throughout the landscape. A stable forage supply in hot, dry years would be provided only by extensive and moderate farming, which allows the development of an insulating tree cover within grazed pastures. We conclude that such structural landscape diversity would grant wood-pastures with a buffering potential in the face of climate change in the forthcoming decades.

  17. Effects of Saccharomyces cerevisiae fermentation product on in vitro fermentation and microbial communities of low-quality forages and mixed diets.

    Science.gov (United States)

    Mao, Hui-ling; Mao, Hua-long; Wang, J K; Liu, J X; Yoon, I

    2013-07-01

    Two experiments were conducted to investigate the effects of a Saccharomyces cerevisiae fermentation product (XP, Diamond V, Cedar Rapids, IA) on in vitro ruminal fermentation of single forage and mixed diets. In Exp. 1, an in vitro test was used to determine the effects of various concentrations (0, 1, 2, and 3 g/L) of XP on ruminal fermentation of the major forage sources of China (rice straw, RS; corn stover, CS; corn silage without grain, CSNG; and corn silage with grain, CSG). Total VFA reached a peak at 1 g/L XP for RS, CSNG, and CSG and increased linearly (P forages except CSNG. The population of Ruminococcus flavefaciens increased (P forages and mixed diets by stimulating the number of fiber-digesting rumen microbes, especially fungi populations.

  18. Production parameters and forage loss of oat and rye grass pastures managed with beef heifers fed diets with energy supplementation

    Directory of Open Access Journals (Sweden)

    Luiz Angelo Damian Pizzuti

    2012-08-01

    Full Text Available Production parameters of intercropped pastures of oat and rye grass managed with beef heifers supplemented with brown rice meal and/or protected fat were evaluated. Twenty-eight Charolais × Nellore crossbred heifers at initial average age of 18 months and initial average live weight of 274.9 kg were utilized in the experiment. Animals were kept on oat + rye grass pastures and distributed in the following treatments: no-supplementation (NS: heifers kept only in pastures; Megalac (MEG: supplementation with protected fat; brown rice meal (BRM: supplementation with BRM; BRM + MEG: supplementation with BRM plus protected fat. The greater participation of oat leaf was from July 5th to August 10th, 2009 and of rye grass, from August 30th to September 26th, 2009. The crude protein content increased until the 55th day (225.1 g/kg. Pasture total digestible nutrients presented a cubic behavior, with an average of 722.0 g/kg. The highest supply of leaf blades, 5.17 kg of dry matter/100 kg of live weight, was found in the second period. Pasture intake increased throughout the periods. Forage mass and support capacity of the animal did not differ between treatments, presenting means of 1245.02 kg of dry matter/ha and 882 kg of live weight/ha, respectively. Stoking rate, forage loss and pasture intake were not affected by the treatments. Supplementation of beef heifers with rice meal and/or protected fat did not change production parameters of oat + rye grass pastures or pasture intake. Increase in daily accumulation rate of dry matter and supporting capacity of the animals increases forage losses.

  19. Bumblebee vibration activated foraging

    OpenAIRE

    Su, Dan Kuan-Nien

    2009-01-01

    The ability use vibrational signals to activate nestmate foraging is found in the highly social bees, stingless bees and honey bees, and has been hypothesized to exist in the closely related, primitively eusocial bumble bees. We provide the first strong and direct evidence that this is correct. Inside the nest, bumble bee foragers produce brief bursts of vibration (foraging activation pulses) at 594.5 Hz for 63±26 ms (velocityRMS=0.46±0.02mm/s, forceRMS=0.8±0.2 mN. Production of these vibrati...

  20. Effects of maturity and harvest season of grass-clover silage and of forage-to-concentrate ratio on milk production of dairy cows

    DEFF Research Database (Denmark)

    Alstrup, L; Søegaard, K; Weisbjerg, M R

    2016-01-01

    This study examined the effects of maturity and season of harvest of grass-clover silages and forage:concentrate ratio (FCR) on feed intake, milk production, chewing activity, digestibility, and fecal consistency of Holstein dairy cows. Comparison included 2 cuts in spring season (early and late...... kilogram of NDF increased with LFCR. This study indicates that silages from summer cuts have a similar value for milk production as do spring cuts, when forage digestibility is taken into account. Moreover, it appears that supplementation of extra concentrate has no effect on ECM production when forages......) and 2 cuts in summer season (early and late) combined with high FCR (80:20; HFCR) and low FCR (50:50; LFCR). The experiment included 24 lactating Holstein cows arranged as 2 repeated 4 × 4 Latin squares with four 21-d periods and included measurements of feed composition, feed intake, milk production...

  1. Forages and Pastures Symposium: assessing drought vulnerability of agricultural production systems in context of the 2012 drought.

    Science.gov (United States)

    Kellner, O; Niyogi, D

    2014-07-01

    Weather and climate events and agronomic enterprise are coupled via crop phenology and yield, which is temperature and precipitation dependent. Additional coupling between weather and climate and agronomic enterprise occurs through agricultural practices such as tillage, irrigation, erosion, livestock management, and forage. Thus, the relationship between precipitation, temperature, and yield is coupled to the relationship between temperature, precipitation, and drought. Unraveling the different meteorological and climatological patterns by comparing different growing seasons provides insight into how drought conditions develop and what agricultural producers can do to mitigate and adapt to drought conditions. The 2012 drought in the United States greatly impacted the agricultural sector of the economy. With comparable severity and spatial extent of the droughts of the 1930s, 1950s, and 1980s, the 2012 drought impacted much of the U.S. crop and livestock producers via decreased forage and feed. This brief summary of drought impacts to agricultural production systems includes 1) the basics of drought; 2) the meteorology and climatology involved in forecasting, predicting, and monitoring drought with attribution of the 2012 drought explored in detail; and 3) comparative analysis completed between the 2011 and 2012 growing season. This synthesis highlights the complex nature of drought in agriculture production systems as producers prepare for future climate variability.

  2. Intensive rainfed and irrigated forage crop production for Mediterranean Italian Buffalo feeding

    Directory of Open Access Journals (Sweden)

    N. Berardo

    2010-02-01

    Full Text Available Buffalo intensive husbandry represents the most lucrative dairy activity in Campania Region. The main forage crop system used in this area are based on winter Italian reygrass (Lolium multiflorum Lam. and spring corn (Zea mays L.. The continuous growing of this crops stressed the soil with a consequent reduction of yield potential. The experiment aimed to assess the agronomic and nutritive feeding value of Italian ryegrasscorn vs other cropping systems (models based on double rotated legumes and graminaceous crops grown under irrigated and rainfed water supply.

  3. Genome-Wide association mapping of loci associated with plant growth and forage production under salt stress in alfalfa (Medicago sativa L.)

    Science.gov (United States)

    Salinity tolerance is highly desirable to sustain alfalfa production in marginal lands that have been rendered saline. In this study, we used a diverse panel of alfalfa accessions for mapping loci associated with plant growth and forage production under salt stress using genome-wide association stud...

  4. Skill ontogeny among Tsimane forager-horticulturalists.

    Science.gov (United States)

    Schniter, Eric; Gurven, Michael; Kaplan, Hillard S; Wilcox, Nathaniel T; Hooper, Paul L

    2015-09-01

    We investigate whether age profiles of Tsimane forager-horticulturalists' reported skill development are consistent with predictions derived from life history theory about the timing of productivity and reproduction. Previous studies of forager skill development have often focused on a few abilities (e.g. hunting), and neglected the broad range of skills and services typical of forager economies (e.g. childcare, craft production, music performance, story-telling). By systematically examining age patterns in reported acquisition, proficiency, and expertise across a broad range of activities including food production, childcare, and other services, we provide the most complete skill development study of a traditional subsistence society to date. Our results show that: (1) most essential skills are acquired prior to first reproduction, then developed further so that their productive returns meet the increasing demands of dependent offspring during adulthood; (2) as postreproductive adults age beyond earlier years of peak performance, they report developing additional conceptual and procedural proficiency, and despite greater physical frailty than younger adults, are consensually regarded as the most expert (especially in music and storytelling), consistent with their roles as providers and educators. We find that adults have accurate understandings of their skillsets and skill levels -an important awareness for social exchange, comparison, learning, and pedagogy. These findings extend our understanding of the evolved human life history by illustrating how changes in embodied capital and the needs of dependent offspring predict the development of complementary skills and services in a forager-horticulturalist economy. © 2015 Wiley Periodicals, Inc.

  5. Foraging range and habitat use by Cape Vulture Gyps coprotheres from the Msikaba colony, Eastern Cape province, South Africa

    Directory of Open Access Journals (Sweden)

    Morgan B. Pfeiffer

    2015-03-01

    Full Text Available Despite the extent of subsistence farmland in Africa, little is known about endangered species that persist within them. The Cape Vulture (Gyps coprotheres is regionally endangered in southern Africa and at least 20% of the population breeds in the subsistence farmland area previously known as the Transkei in the Eastern Cape province of South Africa. To understand their movement ecology, adult Cape Vultures (n = 9 were captured and fitted with global positioning system/global system for mobile transmitters. Minimum convex polygons (MCPs,and 99% and 50% kernel density estimates (KDEs were calculated for the breeding and non breeding seasons of the Cape Vulture. Land use maps were constructed for each 99% KDE and vulture locations were overlaid. During the non-breeding season, ranges were slightly larger(mean [± SE] MCP = 16 887 km2 ± 366 km2 than the breeding season (MCP = 14 707 km2 ± 2155 km2. Breeding and non-breeding season MCPs overlapped by a total of 92%. Kernel density estimates showed seasonal variability. During the breeding season, Cape Vultures used subsistence farmland, natural woodland and protected areas more than expected. In the non-breeding season, vultures used natural woodland and subsistence farmland more than expected, and protected areas less than expected. In both seasons, human-altered landscapes were used less, except for subsistence farmland.Conservation implications: These results highlight the importance of subsistence farm land to the survival of the Cape Vulture. Efforts should be made to minimise potential threats to vultures in the core areas outlined, through outreach programmes and mitigation measures.The conservation buffer of 40 km around Cape Vulture breeding colonies should be increased to 50 km.

  6. Effects of forage type and extruded linseed supplementation on methane production and milk fatty acid composition of lactating dairy cows.

    Science.gov (United States)

    Livingstone, K M; Humphries, D J; Kirton, P; Kliem, K E; Givens, D I; Reynolds, C K

    2015-06-01

    Replacing dietary grass silage (GS) with maize silage (MS) and dietary fat supplements may reduce milk concentration of specific saturated fatty acids (SFA) and can reduce methane production by dairy cows. The present study investigated the effect of feeding an extruded linseed supplement on milk fatty acid (FA) composition and methane production of lactating dairy cows, and whether basal forage type, in diets formulated for similar neutral detergent fiber and starch, altered the response to the extruded linseed supplement. Four mid-lactation Holstein-Friesian cows were fed diets as total mixed rations, containing either high proportions of MS or GS, both with or without extruded linseed supplement, in a 4×4 Latin square design experiment with 28-d periods. Diets contained 500 g of forage/kg of dry matter (DM) containing MS and GS in proportions (DM basis) of either 75:25 or 25:75 for high MS or high GS diets, respectively. Extruded linseed supplement (275 g/kg ether extract, DM basis) was included in treatment diets at 50 g/kg of DM. Milk yields, DM intake, milk composition, and methane production were measured at the end of each experimental period when cows were housed in respiration chambers. Whereas DM intake was higher for the MS-based diet, forage type and extruded linseed had no significant effect on milk yield, milk fat, protein, or lactose concentration, methane production, or methane per kilogram of DM intake or milk yield. Total milk fat SFA concentrations were lower with MS compared with GS-based diets (65.4 vs. 68.4 g/100 g of FA, respectively) and with extruded linseed compared with no extruded linseed (65.2 vs. 68.6 g/100 g of FA, respectively), and these effects were additive. Concentrations of total trans FA were higher with MS compared with GS-based diets (7.0 vs. 5.4 g/100 g of FA, respectively) and when extruded linseed was fed (6.8 vs. 5. 6g/100 g of FA, respectively). Total n-3 FA were higher when extruded linseed was fed compared with no

  7. Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input

    DEFF Research Database (Denmark)

    Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman

    2016-01-01

    with either a high or a low rate of mineral nitrogen (N) fertilizer. Life cycle assessment (LCA) was used to evaluate the carbon footprint (global warming potential) of the grassland management including measured nitrous oxide (N2O) emissions after sward incorporation. Without applying any mineral N...... in the high fertilizer treatment. Nitrous oxide emissions were highest in the treatments containing legumes. The LCA showed that the low input N systems had markedly lower carbon footprint values than crops from the high N input system with the pure stand legumes without N fertilization having the lowest...... carbon footprint. Thus, a reduction in N fertilizer application rates in the low input systems offsets increased N2O emissions after forage legume treatments compared to grass plots due to the N fertilizer production-related emissions. When including the subsequent wheat yield in the total aboveground...

  8. Cumulative and residual effects of repeated sewage sludge applications: forage productivity and soil quality implications in South Florida, USA.

    Science.gov (United States)

    Sigua, Gilbert C; Adjei, Martin B; Rechcigl, Jack E

    2005-01-01

    The cow-calf (Bos taurus) industry in subtropical United States and other parts of the world depends almost totally on grazed pastures. Establishment of complete, uniform stand of bahiagrass (BG) in a short time period is important economically. Failure to obtain a good BG stand early means increased encroachment of weeds and the loss of not only the initial investment costs, but production and its cash value. Forage production often requires significant inputs of lime, N fertilizer, and less frequently of P and K fertilizers. Domestic sewage sludge or biosolids, composted urban plant debris, waste lime, phosphogypsum, and dredged materials are examples of materials that can be used for fertilizing and liming pastures. Perennial grass can be a good choice for repeated applications of sewage sludge. Although sewage sludge supply some essential plant nutrients and provide soil property-enhancing organic matter, land-application programs still generate some concerns because of possible health and environmental risks involved. The objectives of this study were to evaluate the cumulative and residual effects of repeated applications of sewage sludge on (i) bahiagrass (BG, Paspalum notaturn Flügge) production over years with (1997-2000) and without (2001-2002) sewage sludge applications during a 5-yr period, and (ii) on nutrients status of soil that received annual application of sewage sludge from 1997 to 2000 compared with test values of soils in 2002 (with no sewage sludge application) in South Florida. The field experiment was conducted at the University of Florida Agricultural Research and Education Center, Ona, FL (27 degrees 26'N, 82 degrees 55'W) on a Pomona fine sandy soil. With the exception of the control, BG plots received annual sewage sludge and chemical fertilizers applications to supply 90 or 180 kg total N ha(-1) yr(-1) from 1997 to 2000. Land application of sewage sludge and fertilizer ceased in 2001 season. In early April 1998, 1999, and 2000, plots

  9. Productivity and carbon footprint of perennial grass-forage legume intercropping strategies with high or low nitrogen fertilizer input.

    Science.gov (United States)

    Hauggaard-Nielsen, Henrik; Lachouani, Petra; Knudsen, Marie Trydeman; Ambus, Per; Boelt, Birte; Gislum, René

    2016-01-15

    A three-season field experiment was established and repeated twice with spring barley used as cover crop for different perennial grass-legume intercrops followed by a full year pasture cropping and winter wheat after sward incorporation. Two fertilization regimes were applied with plots fertilized with either a high or a low rate of mineral nitrogen (N) fertilizer. Life cycle assessment (LCA) was used to evaluate the carbon footprint (global warming potential) of the grassland management including measured nitrous oxide (N2O) emissions after sward incorporation. Without applying any mineral N fertilizer, the forage legume pure stand, especially red clover, was able to produce about 15 t above ground dry matter ha(-1) year(-1) saving around 325 kg mineral Nfertilizer ha(-1) compared to the cocksfoot and tall fescue grass treatments. The pure stand ryegrass yielded around 3t DM more than red clover in the high fertilizer treatment. Nitrous oxide emissions were highest in the treatments containing legumes. The LCA showed that the low input N systems had markedly lower carbon footprint values than crops from the high N input system with the pure stand legumes without N fertilization having the lowest carbon footprint. Thus, a reduction in N fertilizer application rates in the low input systems offsets increased N2O emissions after forage legume treatments compared to grass plots due to the N fertilizer production-related emissions. When including the subsequent wheat yield in the total aboveground production across the three-season rotation, the pure stand red clover without N application and pure stand ryegrass treatments with the highest N input equalled. The present study illustrate how leguminous biological nitrogen fixation (BNF) represents an important low impact renewable N source without reducing crop yields and thereby farmers earnings. Copyright © 2015. Published by Elsevier B.V.

  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. Effects of feeding fatty acid calcium and the interaction of forage quality on production performance and biochemical indexes in early lactation cow.

    Science.gov (United States)

    Hu, Z Y; Yin, Z Y; Lin, X Y; Yan, Z G; Wang, Z H

    2015-10-01

    Multiparous early lactation Holstein cows (n = 16) were used in a randomized complete block design to determine the effects of feeding fatty acid calcium and the interaction of forage quality on production performance and biochemical indexes in early lactation cow. Treatments were as follows: (i) feeding low-quality forage without supplying fatty acid calcium (Diet A), (ii) feeding low-quality forage with supplying 400 g fatty acid calcium (Diet B), (iii) feeding high-quality forage without supplying fatty acid calcium (Diet C) and (iv) feeding high-quality forage with supplying 400 g fatty acid calcium. This experiment consisted 30 days. The milk and blood samples were collected in the last day of the trail. Intakes were recorded in the last 2 days of the trail. Supplementation of fatty acid calcium decreased significantly dry matter intake (DMI) (p < 0.01). Addition fatty acid calcium decreased milk protein percentage (p < 0.01) and milk SNF percentage (p < 0.01), but increased MUN (p < 0.05). Supplemented fatty acid decreased concentration of blood BHBA (p < 0.05), but increased TG, NEFA, glucagon, GLP-1, CCK, leptin, ApoA-IV, serotonin and MSH concentration in blood, the CCK concentration and feed intake showed a significant negative correlation (p < 0.05). Journal of Animal Physiology and Animal Nutrition © 2015 Blackwell Verlag GmbH.

  12. 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

  13. Effects of different fresh-cut forages and their hays on feed intake, digestibility, heat production, and ruminal methane emission by Boer x Spanish goats.

    Science.gov (United States)

    Puchala, R; Animut, G; Patra, A K; Detweiler, G D; Wells, J E; Varel, V H; Sahlu, T; Goetsch, A L

    2012-08-01

    Twenty-four yearling Boer × Spanish wethers were used to assess effects of different forages, either fresh (Exp. 1) or as hay (Exp. 2), on feed intake, digestibilities, heat production, and ruminal methane emission. Treatments were: 1) Sericea lespedeza (SER; Lespedeza cuneata), a legume high in condensed tannins (CT; 20% and 15% in fresh forage and hay, respectively), 2) SER supplemented with polyethylene glycol (SER-PEG; 25 g/d), 3) alfalfa (Medicago sativa), a legume low in CT (ALF), and 4) sorghum-sudangrass (Sorghum bicolor), a grass low in CT (GRASS). Experiments were 22 d, which included 16 d for acclimatization followed by a 6-d period for fecal and urine collection, and gas exchange measurement (last 2 d). Intake of OM was 867, 823, 694, and 691 g/d (SEM = 20.1) with fresh forage, and 806, 887, 681, and 607 g/d with hay for SER, SER-PEG, ALF, and GRASS, respectively (SEM = 46.6). Apparent total tract N digestion was greater for SER-PEG vs. SER (P forage (46.3%, 66.5%, 81.7%, and 73.2%; SEM = 1.71) and hay (49.7%, 71.4%, 65.4%, and 54.8% for SER, SER-PEG, ALF, and GRASS, respectively; SEM = 1.57). Intake of ME was similar among treatments with fresh forage (8.24, 8.06, 7.42, and 7.70 MJ/d; SEM = 0.434) and with hay was greater for SER-PEG than ALF (P forage (P forage (6.6, 8.3, 9.4, and 9.2%; SEM = 0.64) and hay (4.3, 4.9, 6.4, and 6.7% for SER, SER-PEG, ALF, and GRASS, respectively; SEM = 0.38). In summary, methane emission in this short-term experiment was similar between a legume and grass low in CT as fresh forage and hay. The CT in SER markedly decreased N digestibility and elicited a moderate decline in ruminal methane emission. Supplementation with PEG alleviated the effect of CT on N digestibility but not ruminal methane emission, presumably because of different modes of action. In conclusion, potential of using CT-containing forage as a means of decreasing ruminal methane emission requires further study, such as with longer feeding periods.

  14. Dry matter yields and quality of forages derived from grass species and organic production methods (year 111).

    Science.gov (United States)

    Pholsen, S; Rodchum, P; Higgs, D E B

    2014-07-01

    This third year work was carried on at Khon Kaen University during the 2008-2009 to investigate dry matter yields of grass, grass plus legumes, grown on Korat soil series (Oxic Paleustults). The experiment consisted of twelve-treatment combinations of a 3x4 factorial arranged in a Randomized Complete Block Design (RCBD) with four replications. The results showed that Dry Matter Yields (DMY) of Ruzi and Guinea grass were similar with mean values of 6,585 and 6,130 kg ha(-1) whilst Napier gave the lowest (884 kg ha(-1)). With grass plus legume, grass species and production methods gave highly significant dry matter yields where Guinea and Ruzi gave dry matter yields of 7,165 and 7,181 kg ha(-1), respectively and Napier was the least (2,790 kg ha(-1)). The production methods with the use of cattle manure gave the highest DMY (grass alone) of 10,267 kg ha(-1) followed by Wynn and Verano with values of 6,064 and 3,623 kg ha(-1), respectively. Guinea plus cattle manure gave the highest DMY of 14,599 kg ha(-1) whilst Ruzi gave 12,977 kg ha(-1). Guinea plus Wynn gave DMY of 7,082 kg ha(-1). Ruzi plus Verano gave DMY of 6,501 kg ha(-1). Forage qualities of crude protein were highest with those grown with grass plus legumes. Some prospects in improving production were discussed.

  15. Simulating mechanisms for dispersal, production and stranding of small forage fish in temporary wetland habitats

    Science.gov (United States)

    Yurek, Simeon; DeAngelis, Donald L.; Trexler, Joel C.; Jopp, Fred; Donalson, Douglas D.

    2013-01-01

    Movement strategies of small forage fish (<8 cm total length) between temporary and permanent wetland habitats affect their overall population growth and biomass concentrations, i.e., availability to predators. These fish are often the key energy link between primary producers and top predators, such as wading birds, which require high concentrations of stranded fish in accessible depths. Expansion and contraction of seasonal wetlands induce a sequential alternation between rapid biomass growth and concentration, creating the conditions for local stranding of small fish as they move in response to varying water levels. To better understand how landscape topography, hydrology, and fish behavior interact to create high densities of stranded fish, we first simulated population dynamics of small fish, within a dynamic food web, with different traits for movement strategy and growth rate, across an artificial, spatially explicit, heterogeneous, two-dimensional marsh slough landscape, using hydrologic variability as the driver for movement. Model output showed that fish with the highest tendency to invade newly flooded marsh areas built up the largest populations over long time periods with stable hydrologic patterns. A higher probability to become stranded had negative effects on long-term population size, and offset the contribution of that species to stranded biomass. The model was next applied to the topography of a 10 km × 10 km area of Everglades landscape. The details of the topography were highly important in channeling fish movements and creating spatiotemporal patterns of fish movement and stranding. This output provides data that can be compared in the future with observed locations of fish biomass concentrations, or such surrogates as phosphorus ‘hotspots’ in the marsh.

  16. A New Strategy for Utilizing Rice Forage Production Using a No-Tillage System to Enhance the Self-Sufficient Feed Ratio of Small Scale Dairy Farming in Japan

    Directory of Open Access Journals (Sweden)

    Windi Al Zahra

    2014-08-01

    Full Text Available Rice forage systems can increase the land use efficiency in paddy fields, improve the self-sufficient feed ratio, and provide environmental benefits for agro-ecosystems. This system often decreased economic benefits compared with those through imported commercial forage feed, particularly in Japan. We observed the productivities of winter forage after rice harvest between conventional tillage (CT and no-tillage (NT in a field experiment. An on-farm evaluation was performed to determine the self-sufficient ratio of feed and forage production costs based on farm evaluation of the dairy farmer and the rice grower, who adopted a rice forage system. The field experiment detected no significant difference in forage production and quality between CT and NT after rice harvest. However, the production cost was dramatically decreased by 28.1% in NT compared with CT. The self-sufficient ratio was 5.4% higher when dairy farmers adopted the rice forage system compared with those using the current management system. Therefore, this study demonstrated the positive benefits for dairy farmers and rice growers in Japan when adopting a rice forage system with NT, which could improve the self-sufficient feed ratio and reduce production costs.

  17. 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.

  18. Short communication: Production response of lactating dairy cows to brachytic forage sorghum silage compared with corn silage from first or second harvest.

    Science.gov (United States)

    Bernard, J K; Tao, S

    2015-12-01

    A completely randomized lactation trial was conducted to compare the production response of lactating Holstein cows to diets based on corn or forage sorghum silage harvested from 2 crops. Corn was planted in March and harvested in July (corn silage-summer; CSS) and a second corn crop was planted in July and harvested in November (corn silage-fall; CSF). A brachytic dwarf brown midrib forage sorghum was planted in April, harvested in July (forage sorghum-summer; FSS), fertilized, and harvested a second time in November (forage sorghum-fall; FSF). All forage was ensiled in plastic bags and stored until the production trial began. Silages contained (dry matter basis) 8.0, 8.5, 9.0, and 9.5% crude protein; 39.0, 38.3, 54.2, and 55.1% neutral detergent fiber; and 3.6, 2.8. 7.7, and 7.8% acid detergent lignin, for CSS, CSF, FSS, and FSF, respectively. Forty-eight mid-lactation Holstein cows (153.5±37.2d in milk, 35.7±6.2kg/d of milk, 3.2±0.6% fat, 611.8±67.0kg of body weight, and 2.96±0.09 body condition score) were assigned randomly to 1 of the 4diets differing in forage source. Cows were individually fed experimental diets once daily behind Calan doors for 5wk. Diets were formulated to contain 38.7% of the experimental forages and balanced to provide equal concentrations of protein, fiber, and energy. No differences were observed in dry matter intake and yields of milk and components, but milk fat percentage was lower for CSS and CSF compared with FSS and FSF, being 3.20, 2.91, 3.42, and 3.53%, respectively. Milk lactose percentage was lower for CSS compared with CSF but was not different from FSS or FSF. Concentrations of milk urea nitrogen were lower for CSS and CSF compared with FSS and FSF (10.6, 13.4, 14.9, and 15.3mg/dL, respectively). No differences were observed in body weight or body condition score change during the trial. Results of this trial suggest that silage produced from brachytic forage sorghum, as either the first or the ratoon crop, can support

  19. Nutritional Characteristics of Forage Grown in South of Benin

    Directory of Open Access Journals (Sweden)

    Nadia Musco

    2016-01-01

    Full Text Available In order to provide recommendations on the most useful forage species to smallholder farmers, eleven grass and eleven legume forages grown in Abomey-Calavi in Republic of Benin were investigated for nutritive value (i.e. chemical composition and energy content and fermentation characteristics (i.e. gas and volatile fatty acid production, organic matter degradability. The in vitro gas production technique was used, incubating the forages for 120 h under anaerobic condition with buffalo rumen fluid. Compared to legume, tropical grass forages showed lower energy (8.07 vs 10.57 MJ/kg dry matter [DM] and crude protein level (16.10% vs 19.91% DM and higher cell wall content (neutral detergent fiber: 63.8% vs 40.45% DM, respectively. In grass forages, the chemical composition showed a quite high crude protein content; the in vitro degradability was slightly lower than the range of tropical pasture. The woody legumes were richer in protein and energy and lower in structural carbohydrates than herbaceous plants, however, their in vitro results are influenced by the presence of complex compounds (i.e. tannins. Significant correlations were found between chemical composition and in vitro fermentation characteristics. The in vitro gas production method appears to be a suitable technique for the evaluation of the nutritive value of forages in developing countries.

  20. 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

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

    OpenAIRE

    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 ...

  2. The effects of kale (Brassica oleracea ssp. acephala), basil (Ocimum basilicum) and thyme (Thymus vulgaris) as forage material in organic egg production on egg quality.

    Science.gov (United States)

    Hammershøj, M; Steenfeldt, S

    2012-01-01

    1. In organic egg production, forage material as part of the diet for laying hens is mandatory. The purpose of the present study was to examine the effect of feeding with forage materials including maize silage, herbs or kale on egg production and various egg quality parameters of the shell, yolk colour, egg albumen, sensory properties, fatty acid and carotenoid composition of the egg yolk. 2. A total of 5 dietary treatments were tested for 5 weeks, consisting of a basal organic feed plus 120 g/hen.d of the following forage materials: 1) maize silage (control), 2) maize silage incl. 15 g/kg basil, 3) maize silage incl. 30 g/kg basil, 4) maize silage incl. 15 g/kg thyme, or 5) fresh kale leaves. Each was supplied to three replicates of 20 hens. A total of 300 hens was used. 3. Feed intake, forage intake and laying rate did not differ with treatment, but egg weight and egg mass produced increased significantly with the kale treatment. 4. The egg shell strength tended to be higher with the kale treatment, and egg yolk colour was significantly more red with the kale treatment and more yellow with basil and kale treatments. The albumen DM content and albumen gel strength were lowest with the thyme treatment. By sensory evaluation, the kale treatment resulted in eggs with less sulphur aroma, higher yolk colour score, and more sweet and less watery albumen taste. Furthermore, the eggs of the kale treatment had significantly higher lutein and β-carotene content. Also, violaxanthin, an orange xanthophyll, tended to be higher in kale and eggs from hens receiving kale. 5. In conclusion, forage material, especially basil and kale, resulted in increased egg production and eggs of high and differentiable quality.

  3. Control of glycerol production by rainbow smelt (Osmerus mordax) to provide freeze resistance and allow foraging at low winter temperatures.

    Science.gov (United States)

    Driedzic, William R; Ewart, K Vanya

    2004-11-01

    The rainbow smelt (Osmerus mordax) is a small anadromous fish that actively feeds under the ice at temperatures as low as the freeze point of seawater. Freezing is avoided through the production of both non-colligative antifreeze protein (AFP) and glycerol that acts in a colligative manner. Glycerol is constantly lost across the gills and skin, thus glycerol production must continue on a sustained basis at low winter temperatures. AFP begins to accumulate in early fall while water temperatures are still high. Glycerol production is triggered when water temperatures decrease to about 5 degrees C. Glycerol levels rapidly increase with carbon flow from dihydroxyacetone phosphate (DHAP) to glycerol 3-phosphate (G3P) to glycerol. Glucose/glycogen serves as the initial carbon source for glycerol accumulation with amino acids contributing thereafter. The period of glycerol accumulation is associated with increases in GPDH mRNA and PEPCK mRNA followed by elevations in protein synthesis and enzyme activities. Plasma glycerol levels may reach in excess of 500 mM in winter. The high freeze resistance allows rainbow smelt to invade water of low temperature and forage for food. The lower the temperature, the higher the glycerol must be, and the higher the glycerol the greater the loss to the environment through diffusion. During the winter, rainbow smelt feed upon protein rich invertebrates with glycerol production being fueled in part by dietary amino acids via the gluconeogenic pathway. At winter temperatures, glycerol is quantitatively more important than AFP in providing freeze resistance of blood; however, the importance of AFPs to other tissues is yet to be assessed. Glycerol levels rapidly plummet in the spring when water temperature is still close to 0 degrees C. During this period, freeze resistance must be provided by AFP alone. Overall, the phenomenon of glycerol production by rainbow smelt reveals an elegant connection of biochemistry to ecology that allows this

  4. PRODUCTIVE AND QUALITATIVE PERFORMANCE OF NATURALIZED AND NATIVE FORAGE LEGUMES IN THE TEMPERATE ZONE OF PUEBLA STATE, MEXICO

    Directory of Open Access Journals (Sweden)

    Juan de Dios Guerrero-Rodríguez

    2015-12-01

    Full Text Available The aim of this study was to evaluate seven species of native and naturalized legumes in terms of forage production and nutritive quality. The control species, Vicia sativa was represented by two varieties, which maintained a high dry matter production at two locations, in one of them, matched by Melilotus albus. The latter species also had high yields of dry matter in two locations, but in one of them the varieties of V. sativa were not successful. Less yielding species were those that had lower fiber concentration, a situation that was in part due to a higher leaf:stem ratio. Medicago polymorpha had the lowest digestibility, which coincided with higher concentrations of neutral and acid detergent fiber. The crude protein concentration was different among species (P<0.0001, where M. polymorpha consistently had low (P<0.05 concentration (16.8% as well as M. albus (17%. Among the species tested in this study, several of them have potential yield and quality to improve the diet of ruminants in the highland region of Puebla State and can replace the vetches. Additionally, even when the climate may be the same, the soil conditions also determine which species can thrive in a region.

  5. Enteric methane production and ruminal fermentation of forage brassica diets fed in continuous culture

    Science.gov (United States)

    The aim of the current study was to determine nutrient digestibility, VFA production, N metabolism, and CH4 production of canola (Brassica napus L.), rapeseed (B. napus L.), turnip (B. rapa L.), and annual ryegrass (Lolium multiflorum Lam.) fed with orchardgrass (Dactylis glomerata L.) in continuous...

  6. Foraging range, habitat use and minimum flight distances of East Atlantic Light-bellied Brent Geese Branta bernicla hrota in their spring staging areas

    DEFF Research Database (Denmark)

    Clausen, Kevin Kuhlmann; Clausen, Preben; Hounisen, Jens Peder

    2013-01-01

    habitats. This might reflect changes in habitat availability, and is probably related to significant declines in Common Eelgrass Zostera marina in both these areas. From a historically rather sedentary lifestyle, which centred around foraging on Zostera beds in fjord habitats, this population now feeds...

  7. 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.

  8. Production and quality of Brachiaria forage plants in southwestern Goiás state - doi: 10.4025/actascianimsci.v33i4.8960

    Directory of Open Access Journals (Sweden)

    Marco Aurélio Carbone Carneiro

    2011-09-01

    Full Text Available The sowing season has great influence on the establishment of forage, as spreading seeds out of season tends to harm productivity. Consequently, the aim of this study was to evaluate sowing seasons, production and bromatological quality of Brachiaria forage species in Mineiros-GO. The experiment was held at IPAF/FIMES, in a typical Quartzarenic Neosol. The experimental treatments consisted of five sowing dates and five cultivars/species of forage grass (Brachiaria brizantha (Hochst cv. Marandú, Brachiaria brizantha cv. Xaraés, Brachiaria hybrid cv. Mulato, Brachiaria decumbens Stapfe and Brachiaria ruziziensis. The experiment was designed in randomized blocks with sub-plots, with four replications, each block represented by a sowing date. Dry matter production was higher in the first and second sowing dates. Cultivar Mulato achieved the highest productivity among the assessed cultivars. The sowing season and cultivars influenced the levels of crude protein, neutral detergent fiber and acid detergent fiber. It is concluded that a marked decrease occurs in dry matter production and bromatological quality of Brachiaria species when the sowing is done after mid-March.

  9. 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

  10. Production and utilization of ensiled forages by beef cattle, dairy cows, pregnant ewes and finishing lambs - A review

    Directory of Open Access Journals (Sweden)

    Tim Keady

    2013-03-01

    Full Text Available This paper reviews the production of, and factors affecting the performance of dairy cows, beef cattle and sheep offered silage based diets in Ireland and UK. Digestibility is the most important factor influencing the feed value of grass silage and consequently animal performance. Each 10 g kg-1 increase in digestive organic matter in the dry matter (DOMD increases milk yield of dairy cows by 0.33 kg d-1, carcass gain of beef cattle by 23.8 g d-1 , carcass gain of finishing lambs by 9.3 g d-1, lamb birth weight by 52.3 g and ewe weight post lambing by 1.3 kg, respectively. Factors influencing feed value of grass silage are discussed including harvest date, wilting, fertilizer management, chop length and use of additives at ensiling. Maize silage increases the performance of cattle and sheep whilst whole crop wheat silage has no beneficial effect. Advances in silage technology, has enabled the ensiling high protein forages, such as red clover, lucerne and kale.

  11. Potential of Legume-Brassica Intercrops for Forage Production and Green Manure: Encouragements from a Temperate Southeast European Environment.

    Science.gov (United States)

    Jeromela, Ana M; Mikić, Aleksandar M; Vujić, Svetlana; Ćupina, Branko; Krstić, Đorđe; Dimitrijević, Aleksandra; Vasiljević, Sanja; Mihailović, Vojislav; Cvejić, Sandra; Miladinović, Dragana

    2017-01-01

    Legumes and brassicas have much in common: importance in agricultural history, rich biodiversity, numerous forms of use, high adaptability to diverse farming designs, and various non-food applications. Rare available resources demonstrate intercropping legumes and brassicas as beneficial to both, especially for the latter, profiting from better nitrogen nutrition. Our team aimed at designing a scheme of the intercrops of autumn- and spring-sown annual legumes with brassicas for ruminant feeding and green manure, and has carried out a set of field trials in a temperate Southeast European environment and during the past decade, aimed at assessing their potential for yields of forage dry matter and aboveground biomass nitrogen and their economic reliability via land equivalent ratio. This review provides a cross-view of the most important deliverables of our applied research, including eight annual legume crops and six brassica species, demonstrating that nearly all the intercrops were economically reliable, as well as that those involving hairy vetch, Hungarian vetch, Narbonne vetch and pea on one side, and fodder kale and rapeseed on the other, were most productive in both manners. Feeling encouraged that this pioneering study may stimulate similar analyses in other environments and that intercropping annual legume and brassicas may play a large-scale role in diverse cropping systems, our team is heading a detailed examination of various extended research.

  12. Potential of Legume–Brassica Intercrops for Forage Production and Green Manure: Encouragements from a Temperate Southeast European Environment

    Science.gov (United States)

    Jeromela, Ana M.; Mikić, Aleksandar M.; Vujić, Svetlana; Ćupina, Branko; Krstić, Đorđe; Dimitrijević, Aleksandra; Vasiljević, Sanja; Mihailović, Vojislav; Cvejić, Sandra; Miladinović, Dragana

    2017-01-01

    Legumes and brassicas have much in common: importance in agricultural history, rich biodiversity, numerous forms of use, high adaptability to diverse farming designs, and various non-food applications. Rare available resources demonstrate intercropping legumes and brassicas as beneficial to both, especially for the latter, profiting from better nitrogen nutrition. Our team aimed at designing a scheme of the intercrops of autumn- and spring-sown annual legumes with brassicas for ruminant feeding and green manure, and has carried out a set of field trials in a temperate Southeast European environment and during the past decade, aimed at assessing their potential for yields of forage dry matter and aboveground biomass nitrogen and their economic reliability via land equivalent ratio. This review provides a cross-view of the most important deliverables of our applied research, including eight annual legume crops and six brassica species, demonstrating that nearly all the intercrops were economically reliable, as well as that those involving hairy vetch, Hungarian vetch, Narbonne vetch and pea on one side, and fodder kale and rapeseed on the other, were most productive in both manners. Feeling encouraged that this pioneering study may stimulate similar analyses in other environments and that intercropping annual legume and brassicas may play a large-scale role in diverse cropping systems, our team is heading a detailed examination of various extended research. PMID:28326095

  13. Emergence, forage production, and ion relations of alfalfa in response to saline waters

    Science.gov (United States)

    Alfalfa (Medicago sativa L) is an important crop utilized in regions under irrigation commonly impacted by salinity. In this study we evaluate the effect of salinity, as a continual process, from emergence to mature plant growth in successive harvests. We studied emergence, biomass production, salt ...

  14. Can reducing tillage and increasing crop diversity benefit grain and forage production?

    Science.gov (United States)

    Benefits of reduced tillage and diverse rotation cropping systems include reversing soil C loss, mitigating greenhouse gas production, and improving soil health. However, adoption of these strategies is lagging, particularly in the upper Midwest, due to a perception that reduced tillage reduces cro...

  15. Uses and potential of DNA technologies in forage, turf, and rangeland crop seed production

    Science.gov (United States)

    DNA markers are used at a greater frequency in seed production. It is beneficial for seed producers to understand how the DNA markers can be used and some of their limitations. These markers have been used to detect contaminants in seed lots of annual ryegrass, thus allowing seed lots to be shippe...

  16. 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

  17. Food limitation of sea lion pups and the decline of forage off central and southern California.

    Science.gov (United States)

    McClatchie, Sam; Field, John; Thompson, Andrew R; Gerrodette, Tim; Lowry, Mark; Fiedler, Paul C; Watson, William; Nieto, Karen M; Vetter, Russell D

    2016-03-01

    California sea lions increased from approximately 50 000 to 340 000 animals in the last 40 years, and their pups are starving and stranding on beaches in southern California, raising questions about the adequacy of their food supply. We investigated whether the declining sea lion pup weight at San Miguel rookery was associated with changes in abundance and quality of sardine, anchovy, rockfish and market squid forage. In the last decade off central California, where breeding female sea lions from San Miguel rookery feed, sardine and anchovy greatly decreased in biomass, whereas market squid and rockfish abundance increased. Pup weights fell as forage food quality declined associated with changes in the relative abundances of forage species. A model explained 67% of the variance in pup weights using forage from central and southern California and 81% of the variance in pup weights using forage from the female sea lion foraging range. A shift from high to poor quality forage for breeding females results in food limitation of the pups, ultimately flooding animal rescue centres with starving sea lion pups. Our study is unusual in using a long-term, fishery-independent dataset to directly address an important consequence of forage decline on the productivity of a large marine predator. Whether forage declines are environmentally driven, are due to a combination of environmental drivers and fishing removals, or are due to density-dependent interactions between forage and sea lions is uncertain. However, declining forage abundance and quality was coherent over a large area (32.5-38° N) for a decade, suggesting that trends in forage are environmentally driven.

  18. Production and quality of Urochloa decumbens (stapf r.d. webster forage co-related to the physical and chemical properties of the soil

    Directory of Open Access Journals (Sweden)

    Flávio Carlos Dalchiavon

    Full Text Available ABSTRACT Frequently degraded pastureland characterized by low soil fertility and compacted surface is the basic environment of Brazilian livestock. The physical and chemical characterization of soil and its co-relationship with forage production are determining factors for performance of animals raised on pasture. The objective was to analyze the forage production of Urochloa decumbens grass correlated, linearly and spatially, with physical and chemical attributes of a savannah soil in Selvíria - MS, Brazil. A geostatistical web was introduced for the collection of soil and plant data, with 120 sampling sites within an area of 56.09 ha. The descriptive analysis of the data was undertaken and linear co-relationships, both simple and multiple, were established between plant and soil properties. Semivariograms were modeled and their respective krigings and cross-validations obtained, coupled to co-krigings (plant and soil. Production of dry matter and crude protein rates of U. decumbens may be estimated by regressions and the mechanical resistance to penetration and gravimetric humidity of the soil evaluated. Since organic matter rate and the gravimetric humidity of the soil are co-related spatially with the rate of crude protein of U. decumbens, they are the best factors to calculate or increase the forage crude protein rate.

  19. Compositional analysis of grain and forage from MON 87427, an inducible male sterile and tissue selective glyphosate-tolerant maize product for hybrid seed production.

    Science.gov (United States)

    Venkatesh, Tyamagondlu V; Breeze, Matthew L; Liu, Kang; Harrigan, George G; Culler, Angela H

    2014-02-26

    Conventional maize hybrid seed production has historically relied upon detasseling using either manual methods or semiautomated processes to ensure the purity of the hybrid cross. Monsanto Co. has developed biotechnology-derived MON 87427 maize with tissue-selective glyphosate tolerance to facilitate the production of hybrid maize seed. MON 87427 utilizes a specific promoter and intron combination to drive expression of CP4 EPSPS protein in vegetative and female reproductive tissues, conferring tolerance to glyphosate. This specific combination of regulatory elements also results in limited or no production of CP4 EPSPS protein in two key male reproductive tissues: pollen microspores, which develop into pollen grains, and tapetum cells that supply nutrients to the pollen. Thus, MON 87427 induces a male sterile phenotype after appropriately timed glyphosate applications. To confer additional benefits of herbicide tolerance and/or insect resistance, MON 87427 was combined with MON 89034 and NK603 by conventional breeding to develop MON 87427 × MON 89034 × NK603. The work described here is an assessment of the nutrient, antinutrient, and secondary metabolite levels in grain and forage tissues of MON 87427 and MON 87427 × MON 89034 × NK603. Results demonstrated that MON 87427 is compositionally equivalent to a near-isogenic conventional comparator. Results from this analysis established that the compositional equivalence observed for the single-event product MON 87427 is extendable to the combined-trait product, MON 87427 × MON 89034 × NK603. With increasing global demand for food production, the development of more efficient seed production strategies is important to sustainable agriculture. The study reported here demonstrated that biotechnology can be applied to simplify hybrid maize seed production without affecting crop composition.

  20. 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.

  1. Shearwater foraging in the Southern Ocean: the roles of prey availability and winds.

    Directory of Open Access Journals (Sweden)

    Ben Raymond

    Full Text Available BACKGROUND: Sooty (Puffinus griseus and short-tailed (P. tenuirostris shearwaters are abundant seabirds that range widely across global oceans. Understanding the foraging ecology of these species in the Southern Ocean is important for monitoring and ecosystem conservation and management. METHODOLOGY/PRINCIPAL FINDINGS: Tracking data from sooty and short-tailed shearwaters from three regions of New Zealand and Australia were combined with at-sea observations of shearwaters in the Southern Ocean, physical oceanography, near-surface copepod distributions, pelagic trawl data, and synoptic near-surface winds. Shearwaters from all three regions foraged in the Polar Front zone, and showed particular overlap in the region around 140 degrees E. Short-tailed shearwaters from South Australia also foraged in Antarctic waters south of the Polar Front. The spatial distribution of shearwater foraging effort in the Polar Front zone was matched by patterns in large-scale upwelling, primary production, and abundances of copepods and myctophid fish. Oceanic winds were found to be broad determinants of foraging distribution, and of the flight paths taken by the birds on long foraging trips to Antarctic waters. CONCLUSIONS/SIGNIFICANCE: The shearwaters displayed foraging site fidelity and overlap of foraging habitat between species and populations that may enhance their utility as indicators of Southern Ocean ecosystems. The results highlight the importance of upwellings due to interactions of the Antarctic Circumpolar Current with large-scale bottom topography, and the corresponding localised increases in the productivity of the Polar Front ecosystem.

  2. The use of less common grass varieties as a factor of increasing forage lands productivity

    Directory of Open Access Journals (Sweden)

    В. Д. Бугайов

    2017-03-01

    Full Text Available Purpose. To assess introduced samples of drought-resistant species of perennial grasses, select a promising parent material and create on its base high-yielding varie­ ies with economic characters. Methods. Field experiment, laboratory testing. Results. The results of studies on introduction and breeding were given aimed to improve drought tolerance of non-traditional perennial grasses under the conditions of the Right-Bank Forest-Steppe zone of Ukraine. Based on the selected parent material, varieties were created by the use of hybridization and ecotype breeding methods and then entered into the State Register of plant varieties suitable for dissemination in Ukraine, among them: intermediate wheatgrass (Elytrigia intermedia (Host Nevski – ‘Hors’, crested wheatgrass (Agropyron cristatum (L. Gaertn. – ‘Petrivskyi’; meadow brome (Bromus riparia Rehm. – ‘Boian’; slender wheatgrass (Roegneria trachycaulon (Link Nevski – ‘Co­umb’. As compared with conventional, relatively drought-tolerant species of smooth brome (Bromopsis inermis (Leyss. Holub – ‘Mars’, increment of dry matter content of these species in the extreme drought conditions of 2011 was increased by 1,52–3,73 t/ha. Under more sufficient moistening conditions of 2012, slender wheatgrass ‘Columb’ was at the level of the сheck variety in terms of this indicator. Other varieties exceeded it by 1.44–3.22 t/ha. The data was given including seed productivity and sowing quality indicators, after-ripening duration and economic fitness of seeds. Conclusions. The use of the recommended varieties of drought-resistant species of perennial grasses as part of grass mixtures will increase significantly the productivity of grasslands and pastures in the current context of climate change.

  3. The Effect of Limestone and Stabilized Nitrogen Fertilizers Application on Soil pH Value and on the Forage Production of Permanent Grassland

    Directory of Open Access Journals (Sweden)

    Pavel Ryant

    2016-01-01

    Full Text Available The changes of soil pH and dry forage yield of permanent grassland after application of dolomitic limestone and stabilized nitrogen fertilizers are described in this paper. The small‑plot experiment was located on semi‑natural grassland at Bohemian‑Moravian Highlands, near village Kameničky (Czech Republic, with poor and acidic soil. The experiment was divided into two blocks, within one of whose dolomitic limestone was applied in autumn 2013. In each block, 4 experimental treatments were applied: 1. control (untreated, 2. Urea, 3. Urea with inhibitor of urease, 4. Urea with inhibitor of nitrification. After liming, the pH/CaCl2 soil values increased in both the first as well as the second year after application. Fertilizing by urea, namely urea with inhibitors, did not significantly influence the pH/CaCl2 values. Dry forage productions in both years were comparable. In comparison to the untreated variants, significant increase in dry forage yield was achieved after application of urea and urea with urease inhibitors. The impact of stabilized fertilizers on the yield was not proven. In case of the limed variants, yield drop by 1.12 t/ha (average of both years was observed; the yield decrease may be connected with disturbance of production potential of the stable community of plant species that had been adapted to acidic locations.

  4. Joint product numerical range and geometry of reduced density matrices

    Science.gov (United States)

    Chen, Jianxin; Guo, Cheng; Ji, Zhengfeng; Poon, Yiu-Tung; Yu, Nengkun; Zeng, Bei; Zhou, Jie

    2017-02-01

    The reduced density matrices of a many-body quantum system form a convex set, whose three-dimensional projection Θ is convex in R3. The boundary ∂Θ of Θ may exhibit nontrivial geometry, in particular ruled surfaces. Two physical mechanisms are known for the origins of ruled surfaces: symmetry breaking and gapless. In this work, we study the emergence of ruled surfaces for systems with local Hamiltonians in infinite spatial dimension, where the reduced density matrices are known to be separable as a consequence of the quantum de Finetti's theorem. This allows us to identify the reduced density matrix geometry with joint product numerical range Π of the Hamiltonian interaction terms. We focus on the case where the interaction terms have certain structures, such that a ruled surface emerges naturally when taking a convex hull of Π. We show that, a ruled surface on ∂Θ sitting in Π has a gapless origin, otherwise it has a symmetry breaking origin. As an example, we demonstrate that a famous ruled surface, known as the oloid, is a possible shape of Θ, with two boundary pieces of symmetry breaking origin separated by two gapless lines.

  5. Effect of grain and forage fractions of corn silage on milk production and composition in dairy cows.

    Science.gov (United States)

    Boivin, M; Gervais, R; Chouinard, P Y

    2013-02-01

    Corn silage (CS) is associated with a reduction in milk fat content. The fact that CS is constituted of a grain and a forage fraction could explain this effect. This experiment evaluated the effect of grain fraction of CS on rumen fermentation, production performance and milk composition. Earless CS (ECS) was harvested after manually removing corn ears from the plant. Whole CS (WCS) was harvested from the same field on the same day. Eight (four ruminally fistulated) multiparous Holstein cows (84 days in milk) were utilized in a double 4 × 4 Latin square with 21-day periods. Treatments were (dry matter (DM) basis) (1) 23.0% WCS; (2) 12.4% ECS plus 10.6% high moisture corn (HMC) to obtain reconstituted CS (RCS); (3) 23.0% ECS; and (4) 23.0% timothy silage (TS). Diets were formulated to be isonitrogenous and were fed as total mixed ration once a day. DM intake (DMI), milk yield, 4.0% fat-corrected milk (FCM), as well as protein concentration and yield were higher for WCS than ECS. Compared with WCS, cows tended to eat less with RCS, and produced less milk and milk protein. However, yield of FCM was similar between WCS and RCS. Milk fat concentration and yield, as well as the specific ratio of t11 18:1 to t10 18:1 in milk fat did not differ among diets. Milk urea-N tended to be higher for ECS than WCS and TS, whereas ruminal NH3-N was higher with ECS than TS. Rumen pH decreased linearly with time after feeding but was not different between treatments. Higher acetate and lower propionate concentration resulted in greater acetate to propionate ratio with ECS compared with WCS. In conclusion, removing grain fraction from CS decreased milk production and modified rumen fermentation without affecting milk fat concentration and yield. Moreover, despite some differences in DMI and total ruminal volatile fatty acid concentration between WCS and RCS, the restoration of FCM yield, using HMC in RCS diets, to a level of production similar to WCS highlights the importance of

  6. Optimal foraging for specific nutrients in predatory beetles

    Science.gov (United States)

    Jensen, Kim; Mayntz, David; Toft, Søren; Clissold, Fiona J.; Hunt, John; Raubenheimer, David; Simpson, Stephen J.

    2012-01-01

    Evolutionary theory predicts that animals should forage to maximize their fitness, which in predators is traditionally assumed equivalent to maximizing energy intake rather than balancing the intake of specific nutrients. We restricted female predatory ground beetles (Anchomenus dorsalis) to one of a range of diets varying in lipid and protein content, and showed that total egg production peaked at a target intake of both nutrients. Other beetles given a choice to feed from two diets differing only in protein and lipid composition selectively ingested nutrient combinations at this target intake. When restricted to nutritionally imbalanced diets, beetles balanced the over- and under-ingestion of lipid and protein around a nutrient composition that maximized egg production under those constrained circumstances. Selective foraging for specific nutrients in this predator thus maximizes its reproductive performance. Our findings have implications for predator foraging behaviour and in the structuring of ecological communities. PMID:22237910

  7. High-quality forage can replace concentrate when cows enter the deposition phase without negative consequences for milk production.

    Science.gov (United States)

    Hymøller, L; Alstrup, L; Larsen, M K; Lund, P; Weisbjerg, M R

    2014-07-01

    LP. Differences in fatty acid composition were small, and de novo synthesis was high (>60%). Energy efficiency was higher on LCFR than on HCFR and no interaction with breed or parity was found. The N efficiency was higher on LP than RP, but with an interaction with breed due to lower N efficiency in Jersey than Holstein cows on HCFR-RP but higher N efficiency in Jersey than Holstein on LCFR-LP. In dairy production, concentrate in the mixed ration can be substituted with high-quality forage during deposition without negative effects on milk yield and composition when a sufficient CP level is ensured. Copyright © 2014 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  8. Genetic Analysis of Seed Yield Components and its Association with Forage Production in Wild and Cultivated Species of Sainfoin

    Directory of Open Access Journals (Sweden)

    A. Najafipoor

    2017-02-01

    Full Text Available Little is known about genetic variation of seed related traits and their association with forage characters in sainfoin. In order to investigate the variation and relationship among seed yield and its components, 93 genotypes from 21 wild and cultivated species of genus Onobrychis were evaluated using a randomized complete block design with four replications at Isfahan University of Technology Research Farm, Isfahan, Iran. Analysis of variance showed that there was significant difference among genotypes, indicating existence of considerable genetic variation in this germplasm. Panicle fertility and panicle length had the most variation in cultivated and the wild genotypes, respectively. Results of correlation analysis showed that seed yield was positively correlated with number of stems per plant and number of seeds per panicle and negatively correlated with panicle length and days to 50% flowering. Seed yield had positive correlation with forage yield in wild species while this correlation was not significant in cultivated one. Cluster analysis classified the genotypes into three groups which separate wild and cultivated species. Based on principal component analysis the first component was related to seed yield and the second one was related to components of forage yield which can be used for selection of high forage and seed yielding genotypes.

  9. 'Snowstorm' a new forage kochia cultivar with improved stature, productivity, and nutritional content for enhanced fall and winter grazing

    Science.gov (United States)

    'Snowstorm' forage kochia (Bassia prostrata [L.] A.J. Scott) (synonym=Kochia prostrata [L.] Schrad.) (Reg. No. CV-_____, PI _____) was released on March 22, 2012, by the USDA-ARS and the Utah Agricultural Experiment Station. Snowstorm was evaluated as OTVSEL and Otavny-select, and was developed as ...

  10. Effects of dehydrated lucerne and soya bean meal on milk production and composition, nutrient digestion, and methane and nitrogen losses in dairy cows receiving two different forages.

    Science.gov (United States)

    Doreau, M; Ferlay, A; Rochette, Y; Martin, C

    2014-03-01

    Dehydrated lucerne is used as a protein source in dairy cow rations, but little is known about the effects of lucerne on greenhouse gas production by animals. Eight Holstein dairy cows (average weight: 582 kg) were used in a replicated 4 × 4 Latin square design. They received diets based on either maize silage (M) or grass silage (G) (45% of diet on dry matter (DM) basis), with either soya bean meal (15% of diet DM) completed with beet pulp (15% of diet DM) (SP) or dehydrated lucerne (L) (30% of diet DM) as protein sources; MSP, ML, GSP and GL diets were calculated to meet energy requirements for milk production by dairy cows and degradable protein for rumen microbes. Dry matter intake (DMI) did not differ among diets (18.0 kg/day DMI); milk production was higher with SP diets than with L diets (26.0 v. 24.1 kg/day), but milk production did not vary with forage type. Milk fatty-acid (FA) composition was modified by both forage and protein sources: L and G diets resulted in less saturated FA, less linoleic acid, more trans-monounsaturated FA, and more linolenic acid than SP and M diets, respectively. Enteric methane (CH4) production, measured by the SF6 tracer method, was higher for G diets than for M diets, but did not differ with protein source. The same effects were observed when CH4 was expressed per kg milk. Minor effects of diets on rumen fermentation pattern were observed. Manure CH4 emissions estimated from faecal organic matter were negatively related to diet digestibility and were thus higher for L than SP diets, and higher for M than G diets; the resulting difference in total CH4 production was small. Owing to diet formulation constraints, N intake was higher for SP than for L diets; interaction between forage type and protein source was significant for N intake. The same statistical effects were found for N in milk. Faecal and urinary N losses were determined from total faeces and urine collection. Faecal N output was lower for M than for G diets but

  11. Optimization of fibrolytic enzyme production by Aspergillus japonicus C03 with potential application in ruminant feed and their effects on tropical forages hydrolysis.

    Science.gov (United States)

    Facchini, Fernanda D A; Vici, Ana C; Benassi, Vivian M; Freitas, Luiz A P; Reis, Ricardo A; Jorge, João A; Terenzi, Héctor F; Polizeli, Maria de Lourdes T M

    2011-10-01

    Fibrolytic enzyme production by Aspergillus japonicus C03 was optimized in a medium containing agro-industrial wastes, supplemented with peptone and yeast extract. A 2(3) full factorial composite and response surface methodology were used to design the experiments and analysis of results. Tropical forages were hydrolyzed by A. japonicus C03 enzymatic extract in different levels, and they were also tested as enzymatic substrate. Optimal production to xylanase was obtained with soybean bran added to crushed corncob (1:3), 0.01% peptone, and 0.2% yeast extract, initial pH 5.0, at 30 °C under static conditions for 5 days of incubation. Optimal endoglucanase production was obtained with wheat bran added to sugarcane bagasse (3:1), 0.01% peptone, and 0.2% yeast extract, initial pH 4.0, at 30 °C, for 6 days, under static conditions. Addition of nitrogen sources as ammonium salts either inhibited or did not influence xylanase production. This enzymatic extract had a good result on tropical forage hydrolyzes and showed better performance in the Brachiaria genera, due to their low cell wall lignin quantity. These results represent a step forward toward the use of low-cost agricultural residues for the production of valuable enzymes with potential application in animal feed, using fermentation conditions.

  12. Satellite Laser Ranging Satellite Orbit Product from NASA CDDIS

    Data.gov (United States)

    National Aeronautics and Space Administration — SLR Satellite Orbit solutions available from the Crustal Dynamics Data Information System (CDDIS). Precise Orbit Determination (POD) solutions in Standard Product 3...

  13. Kinetics fermentation and gas production of the neutral detergent-soluble fraction of fresh forage, silage and hay of Avena sativa

    Directory of Open Access Journals (Sweden)

    V. Piccolo

    2011-03-01

    Full Text Available Neutral detergent treatment to evaluate the structural polysaccharides (NDF removes soluble sugars, pectin substances, starch and the non-carbohydrate fraction (Van Soest, 1991. Despite the widely recognized importance of neutral detergent-soluble carbohydrates (NDS in the early stages of forage digestion, little is known about their digestion kinetics because most in vitro methods have studied the disappearance of insoluble cell wall components. However, knowledge of the degradation characteristics of both fractions is very important to formulate balanced diets for high-yielding animals. Using the in vitro gas production system........

  14. High-quality forage can replace concentrate when cows enter the deposition phase without negative consequences for milk production

    DEFF Research Database (Denmark)

    Hymøller, Lone; Alstrup, Lene; Larsen, Mette Krogh

    2014-01-01

    Mobilization and deposition in cows are different strategies of metabolism; hence, the aim was to study the possibility of reducing the crude protein (CP) supply during deposition to limit the use of protein supplements and minimize the environmental impact. A total of 61 Jersey and 107 Holstein ......, concentrate in the mixed ration can be substituted with high-quality forage during deposition without negative effects on milk yield and composition when a sufficient CP level is ensured....

  15. 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

  16. A properly adjusted forage harvester can save time and money

    Science.gov (United States)

    A properly adjusted forage harvester can save fuel and increase the realizable milk per ton of your silage. This article details the adjustments necessary to minimize energy while maximizing productivity and forage quality....

  17. Perception of dimethyl sulfide (DMS) by loggerhead sea turtles: a possible mechanism for locating high-productivity oceanic regions for foraging.

    Science.gov (United States)

    Endres, Courtney S; Lohmann, Kenneth J

    2012-10-15

    During their long-distance migrations, sea turtles of several species feed on jellyfish and other invertebrates that are particularly abundant in ocean regions characterized by high productivity. An ability to distinguish productive oceanic regions from other areas, and to concentrate foraging activities in locations where prey density is highest, might therefore be adaptive. The volatile compound dimethyl sulfide (DMS) accumulates in the air above productive ocean areas such as upwelling and frontal zones. In principle, DMS might therefore serve as an indicator of high prey density for turtles. To determine whether turtles perceive DMS, juvenile loggerhead sea turtles (Caretta caretta) were placed into a water-filled arena in which DMS and other odorants could be introduced to the air above the water surface. Turtles exposed to air that had passed over a cup containing 10 nmol l(-1) DMS spent more time at the surface with their noses out of the water than control turtles, which were exposed to air that had passed over a cup containing distilled water. Odors that do not occur in the sea (cinnamon, jasmine and lemon) did not elicit increased surface time, implying that the response to DMS is unlikely to reflect a generalized response to any novel odor. The results demonstrate for the first time that sea turtles can detect DMS, an ability that might enable the identification of favorable foraging areas.

  18. The Adaptive Range of 1/f Isometric Force Production

    Science.gov (United States)

    Sosnoff, Jacob J.; Valantine, Andrew D.; Newell, Karl M.

    2009-01-01

    The adaptive range of 1/f dynamics in isometric force output was investigated. Participants produced isometric force to targets with predictable demands (constant and sinusoidal) and 1/f noise waveforms (white, pink, brown, and black) that also varied in the frequency bandwidth represented in the force signal (0-4 Hz, 0-8 Hz, and 0-12 Hz). The…

  19. Neutron activation analysis application for determining iron concentration in forage grasses used in intensive cattle production system; Aplicacao da analise por ativacao com neutrons para determinacao de ferro em forrageiras usadas no sistema intensivo de producao de bovinos de leite

    Energy Technology Data Exchange (ETDEWEB)

    Armelin, Maria Jose A. [Instituto de Pesquisas Energeticas e Nucleares (IPEN), Sao Paulo, SP (Brazil); Primavesi, Odo [Empresa Brasileira de Pesquisa Agropecuaria, Sao Carlos, SP (Brazil). Centro de Pesquisa de Pecuaria do Sudeste

    2002-07-01

    Iron is an essential element to the life. It is an important hemoglobin component and it is involved in the transport of oxygen to cells. A deficiency of iron results in an unsuitable synthesis of hemoglobin and a delay in the growth. Iron contents above the tolerable level in animal feed can cause serious damages to the health and the death in extreme cases. The forages are the main source of feed to cattle in grazing. It is known from the literature, that the growth and the nutritious value of the forage are influenced by specie and physiologic age of the plant, soil fertility and environmental conditions. Therefore, an agronomical evaluations of the forages are necessary before to introduce in an intensive cattle production systems to program adequate grazing management. Neutron activation analysis was applied to evaluate the Fe concentration in the main tropical forage grasses used in intensive dairy cattle production systems in Sao Carlos, SP, Brazil. Iron concentrations were smaller in the rain season than in the dry one. Comparison of results obtained in the analyses of forages with daily requirements of iron in dry matter, showed that the Fe concentration in forages was adequate. (author)

  20. Arboreal forage lichen response to partial cutting of high elevation mountain caribou range in the Quesnel Higland of east-central British Columbia

    Directory of Open Access Journals (Sweden)

    Michaela J. Waterhouse

    2007-04-01

    Full Text Available Group selection silvicultural systems have been recommended for managing mountain caribou (Rangifer tarandus caribou habitat in high elevation Engelmann spruce – subalpine fir forests in east-central British Columbia. We measured the response of arboreal lichen (a key winter forage to harvesting of 30% of the forested area using three partial cutting treatments, which created small (0.03 ha, medium (0.13 ha, and large (1.0 ha openings, and a no-harvest treatment. Treatments were replicated on four sites, and monitored over a ten year post-harvest period. The short-term loss of lichen associated with removal of approximately one third of the trees was partially offset by a significant (P=0.01 increase in lichen abundance on trees in the caribou feeding zone (up to 4.5 m in the three partial cutting treatments relative to trees in the uncut forest. Differences among treatments in the change in lichen composition, as measured by the percentage of Alectoria sarmentosa and Bryoria spp., were marginally significant (P=0.10. The partial cutting treatments showing a greater likelihood of shifting towards more Bryoria spp. than no-harvest treatment (P=0.04. In the year of harvest (1993, larger trees were found to hold more lichen than smaller trees (P=0.04, and live trees supported more lichen than dead trees (P=0.01, but lichen loading was similar among tree species (P=0.51. Tree fall rates were similar among treatments, based on the ten year average (0.6–0.8% of sample trees per year. The results indicate that caribou foraging habitat is maintained in the residual forest when group selection systems that remove only 30% of the trees are applied. Information on the distribution of lichen is useful for developing stand level prescriptions. Providing lichen bearing habitat meets just one of the needs of caribou. A comprehensive approach that considers all factors and their interactions is essential to maintain and recover the threatened mountain

  1. 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, 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

  2. 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

  3. 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

  4. Foraging behaviour, nutrient intake from pasture and performance of free-range growing pigs in relation to feed CP level in two organic cropping systems

    DEFF Research Database (Denmark)

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

    2015-01-01

    in lucerne paddocks LP pigs only had 18% lower daily weight gain (741 v. 900 g) and a 14% poorer feed conversion ratio (2.95 v. 2.54 kg feed/kg weight gain) compared with HP pigs. LP pigs foraging on lucerne used 169 g less concentrate CP/kg weight gain, compared with HP pigs, indicating the nitrogen...... mixture (HP: high protein) or a grain mixture containing 48% less CP (LP: low protein) compared with the high protein feed mixture, from an average live weight of 58 kg to 90 kg in a complete block design in three replicates. The pigs were fed 80% of energy recommendations and had access to 4 m2...... of pasture/pig per day during the 40 days experimental period from September to October 2013. Behavioural observations were carried out 12 times over the entire experimental period. For both crops, LP pigs rooted significantly more compared with HP pigs but the effect of CP level was more pronounced in grass...

  5. Effect of partial replacement of forage neutral detergent fiber with by-product neutral detergent fiber in close-up diets on periparturient performance of dairy cows.

    Science.gov (United States)

    Dann, H M; Carter, M P; Cotanch, K W; Ballard, C S; Takano, T; Grant, R J

    2007-04-01

    The objective of this study was to determine the effect of partial replacement of forage neutral detergent fiber (NDF) with by-product NDF in close-up diets of dairy cattle on periparturient metabolism and performance. Holstein cows (n = 45) and heifers (n = 19) were fed corn silage-based diets containing 1) 30% oat hay, or 2) 15% oat hay and 15% beet pulp from d -21 relative to expected parturition until parturition. After parturition, all animals received the same lactation diet. Animals were group-fed from d -21 to -10 relative to expected parturition and fed individually from d -10 until 14 d in milk. Animals were required to have at least 5 d of prepartum dry matter intake (DMI) data to remain on the study. Data were analyzed as a randomized design and subjected to ANOVA using the MIXED procedure of SAS. Close-up diet did not affect DMI, total tract nutrient digestibility, energy balance, or serum content of nonesterified fatty acids and beta-hydroxybutyrate during the last 5 d prepartum. Prepartum body weight and body condition score were similar between treatments. There was no carryover effect of close-up diet on DMI, energy balance, milk yield, body weight, body condition score, or serum content of nonesterified fatty acids and beta-hydroxybutyrate during the first 14 d in milk. In summary, partial replacement of forage NDF (oat hay) with by-product NDF (beet pulp) did not affect periparturient metabolism or performance.

  6. Multi-objective optimization to improve the product range of baking systems

    NARCIS (Netherlands)

    Hadiyanto, M.; Boom, R.M.; Straten, van G.; Boxtel, van A.J.B.; Esveld, D.C.

    2009-01-01

    The operational range of a food production system can be used to obtain a variation in certain product characteristics. The range of product characteristics that can be simultaneously realized by an optimal choice of the process conditions is inherently limited. Knowledge of this feasible product

  7. Knowledge of Repetitions Range Affects Force Production in Trained Females

    Directory of Open Access Journals (Sweden)

    Israel Halperin, Saied J. Aboodarda, Fabien A. Basset, David G. Behm

    2014-12-01

    Full Text Available Most studies have examined pacing strategies with cyclical activities (running and cycling. It has been demonstrated that males employ different pacing strategies during repeated maximal voluntary contractions (MVCs dependent upon a known endpoint. Since different fatiguing mechanisms have been identified between the genders, it is not known if females use comparable pacing strategies. The purpose of this study was to examine if informing female subjects regarding the number of MVCs to perform would affect force and electromyography (EMG. Twenty well-trained females completed 3 fatiguing protocols in a randomized order. In the control condition participants were informed they would perform twelve MVCs and then actually completed twelve. In the unknown condition they were not told how many MVCs to perform but were stopped after twelve. In the deception condition they were initially informed to perform 6 MVCs, but after the 6th MVC they were asked to perform a few more MVCs and were stopped after twelve. During the first 6 MVCs, forces in the deception condition were greater compared to the unknown (p = 0.021, ES = 0.65, 5% and control (p = 0.022, ES = 0.42, 3% conditions. No differences were found between conditions in the last 6 MVCs. A main effect for repetitions showed force deficits during the first 6 MVCs (p = 0.000, ES = 1.81, 13% and last 6 MVCs (p = 0.05, ES = 0.34, 3%. No differences were found between conditions in biceps and triceps EMG. However, EMG decreased during the first 6 MVCs for biceps (p = 0.001, ES = 1.0, 14% and triceps (p = 0.001, ES = 0.76, 14% across conditions. No differences were found in the last 6 MVCs. The anticipation of performing fewer MVCs led to increased force, whereas no endpoint led to decreased force production.

  8. [Application of near infrared spectroscopy technology (NIRS) in forage field].

    Science.gov (United States)

    Yan, Xu; Bai, Shi-Qie; Yan, Jia-Jun; Gan, You-Min; Dao, Zhi-Xue

    2012-07-01

    The majority of nutrients in ruminants and other herbivores come from forages. Forage quality not only affects the growth and production efficiency of livestock, but also determines the final output and quality of livestock products. Forage quality mainly depends on nutrient concentrations and their digestibility, palatability and the level of presence of antiquality factors and mycotoxins in forage. Near infrared reflectance spectroscopy (NIRS) has been widely used in many research areas because it is a inexpensive, rapid, simple and nondestructive technique offering the potential for qualitative and quantitative analysis. The present paper briefly introduces the principle and characteristics of NIRS, detailedly expounds the application of NIRS in forage quality. In addition, other applications of near infrared spectroscopy technique in forage are also discussed, including forage breeding, identification of variety and classification by kind. This paper comprehensively reviews the status quo of application of NIRS in forage filed, in order to contribute to promoting development of NIRS in this field in China.

  9. Nitrogen transfer between herbivores and their forage species

    NARCIS (Netherlands)

    Sjögersten, S.; Kuijper, D.; Van der Wal, R.; Loonen, M.J.J.E.; Huiskes, A.H.L.; Woodin, S.J.

    2010-01-01

    Herbivores may increase the productivity of forage plants; however, this depends on the return of nutrients from faeces to the forage plants. The aim of this study was to test if nitrogen (N) from faeces is available to forage plants and whether the return of nutrients differs between plant species

  10. Nitrogen transfer between herbivores and their forage species

    NARCIS (Netherlands)

    Sjogersten, Sofie; Kuijper, Dries P. J.; van der Wal, Rene; Loonen, Maarten J. J. E.; Huiskes, Ad H. L.; Woodin, Sarah J.

    Herbivores may increase the productivity of forage plants; however, this depends on the return of nutrients from faeces to the forage plants. The aim of this study was to test if nitrogen (N) from faeces is available to forage plants and whether the return of nutrients differs between plant species

  11. Effect of cutting interval to productivity and quality of bangun-bangun (Coleus amboinicus L. as a forage promising commodity

    Directory of Open Access Journals (Sweden)

    Sajimin

    2011-12-01

    Full Text Available Coleus amboinicus Lour is one of well known plant and commonly consumed by lactating women in North Sumatera. It is high, in iron and carotene contents. The objective of the research was to study the productivity of C. amboinicus at different cutting intervals. An experiment was carried out in glasshouse as pot trial. Four treatments of cutting interval were 30 days, 40 days, 50 days and 60 days with 10 replications. The treatment was arranged in randomized complete design. Parameters measured were shoot dry matter, and crude protein, Cu, Zn and B contents of leaves, at the beginning, middle and end of the experiment. Result shows that dry matter yield was significantly influenced by cutting interval (P <0.05. The highest shoot dry matter production was obtained at 60 days cutting interval (34.1 g /plant and the lowest at 50 days cutting interval (19.6 g/plant. Similarly, crude protein and Cu, Zn and B content of shoot were also highest at 60 days cutting interval. The shoot dry matter production declined from first cutting to seventh cutting. Crude protein content at 60 days cutting interval was in a range of 12.31-15.59%.

  12. Determination of Nutrient Contents and Gas Production Values of Some Legume Forages Grown in the Harran Plain Saline Soils

    Directory of Open Access Journals (Sweden)

    M. Boga

    2014-06-01

    Full Text Available The aim of this study was to determine the nutritive value of some legume species in salt-affected soils of South-East Anatolian region using chemical composition and in vitro gas production kinetics. In this study, Lotus corniculatus, Trifolium alexandrinum, Medicago sativa were sown and tested in four different locations. A 3 by 4 factorial design with 3 legume species and 4 salt levels (non salty electrical conductivity (ECECECEC was used in the study. Results indicated that salinity and plants had no significant effect on ash and ether extract. Dry matter (DM, acid detergent fiber, digestible dry matter, dry matter intake (DMI were affected by plant, salinity and plant×salinity interaction. On the other hand neutral detergent fiber, relative feed value (RFV, and DMI were affected by salinity and plant×salinity interaction. Mineral contents were affected by plant species, salinity and salinity×plants interactions. In vitro gas production, their kinetics and estimated parameters such as were not affected by salinity whereas the gas production up to 48 h, organic matter digestibility, metabolizable energy (ME, and net energy lactation (NEL were affected by plant and plant×salt interaction. Generally RFVs of all species ranged from 120 to 210 and were quite satisfactory in salty conditions. Current results show that the feed value of Medicago sativa is higher compared to Lotus corniculatus and Trifolium alexandrinum.

  13. A BACTERIA FORAGING ALGORITHM FOR SOLVING INTEGRATED MULTI-PERIOD CELL FORMATION AND SUBCONTRACTING PRODUCTION PLANNING IN A DYNAMIC CELLULAR MANUFACTURING SYSTEM

    Directory of Open Access Journals (Sweden)

    S.H. Tang

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: The bacteria foraging algorithm (BFA is a new computation technique inspired by the social foraging behaviour of Escherichia coli (E. coli bacteria. Since the introduction of the BFA by Kevin M. Passino, there have been many challenges in employing this algorithm to problems other than those for which the algorithm was proposed. This research aims to apply this emerging optimisation algorithm to develop a mixed-integer programming model for designing cellular manufacturing systems (CMSs, and production planning in dynamic environments. In dynamic environments, product mix and part demand vary under multi-period planning horizons. Thus the best-designed cells for one period may not be adequate for subsequent periods, requiring their reconstruction. The advantages of the proposed model are as follows: consideration of batch inter-cell and intra-cell material handling by assuming the sequence of operations, allowing for alternative process plans for part types, and consideration of machine copying, with an emphasis on the effect of trade-offs between production and outsourcing costs. The goal is to minimise the sum of the machines’ constant and variable costs, inter-cell and intra-cell material handling costs, reconstruction costs, partial subcontracting costs, and inventory carrying costs. In addition, a newly-developed BFA-based optimisation algorithm has been compared with the branch and bound algorithm. The results suggest that the proposed algorithm performs better than related works.

    AFRIKAANSE OPSOMMING: Die ‘bacteria foraging algorithm’ (BFA is ‘n berekeningstegniek gebaseeer op die sosiale soekgedrag van Escherichia coli (E. coli bakterieë. Sedert die bekendstelling van BFA was daar talle uitdagings oor toepassings van die algoritme op ander probleme as dié waarvoor dit ontwikkel is. Dié navorsing poog om deur toepassing van die algoritme ‘n gemengde heelgetalprogrammeringmodel te ontwikkel vir die

  14. Responses of herbage and browse production to six range management strategies.

    Science.gov (United States)

    H. Reed Sanderson; Thomas M. Quigley; Arthur R. Tiedemann

    1990-01-01

    From 1977 through 1986, herbage and browse production was sampled on 619 sites representing 10 ecosystems and 51 resource units on the Oregon Range Evaluation study area. We determined the effects of six range management strategies and cultural treatments on combined herbage and browse production. Mean herbage and browse production on the forest ecosystems was 145...

  15. 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 .... Figure 1 The correlation between digestion of dry matter in vitro and in vitro yield of VFA from six grass species, different extents of digestion.

  16. Perennial forages as second generation bioenergy crops.

    Science.gov (United States)

    Sanderson, Matt A; Adler, Paul R

    2008-05-01

    The lignocellulose in forage crops represents a second generation of biomass feedstock for conversion into energy-related end products. Some of the most extensively studied species for cellulosic feedstock production include forages such as switchgrass (Panicum virgatum L.), reed canarygrass (Phalaris arundinacea L.), and alfalfa (Medicago sativa L.). An advantage of using forages as bioenergy crops is that farmers are familiar with their management and already have the capacity to grow, harvest, store, and transport them. Forage crops offer additional flexibility in management because they can be used for biomass or forage and the land can be returned to other uses or put into crop rotation. Estimates indicate about 22.3 million ha of cropland, idle cropland, and cropland pasture will be needed for biomass production in 2030. Converting these lands to large scale cellulosic energy farming could push the traditional forage-livestock industry to ever more marginal lands. Furthermore, encouraging bioenergy production from marginal lands could directly compete with forage-livestock production.

  17. Assessing the efficacy of dredged materials from Lake Panasoffkee, Florida: implication to environment and agriculture. Part 2: pasture establishment and forage productivity.

    Science.gov (United States)

    Sigua, Gilbert C; Holtkamp, Mike L; Coleman, Samuel W

    2004-01-01

    Current dredged material disposal alternatives have several limitations. Options for dealing with dredged materials include leaving them alone, capping them with clean sediments, placing them in confined facilities, disposing of them at upland sites, treating them chemically, or using them for wetlands creation or other beneficial uses The ability to reuse lake-dredge materials (LDM) for agricultural purposes is important because it reduces the need for offshore disposal and provides an alternative to disposal of the materials in landfills. Often these materials can be obtained at little or no cost to the farmers or landowners. Thus, forage production offers an alternative to waste management since nutrients in the LDM are recycled into crops that are not directly consumed by humans. The objective of this study (Part 2) were to: (1) assess dredge materials from Lake Panasoffkee, Florida as a soil amendment to establish bahiagrass (BG) in a subtropical beef cattle pasture in Sumter County, Florida; and (2) determine the effect of LDM application on the crude protein (CP) and nutrient uptake of BG. This series of two papers aims at providing assessment of the efficacy of lake-dredged materials especially its implication to environment (soil quality, Part 1) and agriculture (forage quality and pasture establishment, Part 2). The experimental treatments that were evaluated consisted of different ratios of natural soil (NS) to LDM: LDM0 (100% NS:0% LDM); LDM25 (75% NS:25% LDM); LDM50 (50% NS:50% LDM); LDM75 (25% NS:75% LDM); and LDM100 (0% NS:100% LDM). Bahiagrass plots at its early establishment were cut to a 5-cm stubble height on Julian days 112 and harvested to the same stubble height on Julian days 238 and on Julian days 546 following the double-ring method. Field layout was based on the principle of a completely randomized block design with four replications. Plant samples harvested at 546 Julian days were ground to pass through a 1-mm mesh screen in a Wiley mill

  18. Foraging ecology of least terns and piping plovers nesting on Central Platte River sandpits and sandbars

    Science.gov (United States)

    Sherfy, Mark H.; Anteau, Michael J.; Shaffer, Terry L.; Sovada, Marsha A.; Stucker, Jennifer H.

    2012-01-01

    Federally listed least terns (Sternula antillarum) and piping plovers (Charadrius melodus) nest on riverine sandbars on many major midcontinent river systems. On the Central Platte River, availability of sandbar habitat is limited, and both species nest on excavated sandpits in the river's floodplain. However, the extent to which sandpit-nesting birds use riverine habitats for foraging is unknown. We evaluated use of foraging habitats by least terns and piping plovers by collecting data on movements, behavior, foraging habitat, and productivity. We radiomarked 16 piping plovers and 23 least terns in 2009-2010 and monitored their movements using a network of fixed telemetry dataloggers. Piping plovers were detected primarily by the datalogger located in their nesting sandpit, whereas least terns were more frequently detected on dataloggers outside of the nesting sandpit. Telemetry data and behavioral observations showed that least terns tended to concentrate at the Kearney Canal Diversion Gates, where forage fish were apparently readily available. Fish sampling data suggested that forage fish were more abundant in riverine than in sandpit habitats, and behavioral observations showed that least terns foraged more frequently in riverine than in sandpit habitats. Piping plovers tended to forage in wet substrates along sandpit shorelines, but also used dry substrates and sandpit interior habitats. The greater mobility of least terns makes a wider range of potential foraging habitats available during brood rearing, making them able to exploit concentrations of fish outside the nesting colony. Thus, our data suggest that different spatial scales should be considered in managing nesting and foraging habitat complexes for piping plovers and least terns.

  19. Droughts of the twentieth and early twenty-first centuries: Influences on the production of beef and forage in Kentucky, USA.

    Science.gov (United States)

    Craft, Kortney E; Mahmood, Rezaul; King, Stephen A; Goodrich, Gregory; Yan, Jun

    2016-10-28

    Drought affects societies world-wide in many different ways. It is a natural hazard that is complex and not well understood and as a result, its impacts are often poorly documented. The purpose of this research is to quantify (in dollars) the impacts of drought on Kentucky's beef and forage (hay) production. Observations suggest that the most important droughts in Kentucky occurred in 1930-31, 1940-42, 1952-55, 1987-88, 1999-2000 and 2007. The total state revenue for these commodities were analyzed during these severe drought years and non-drought years. The research estimated revenue deficit from these severe droughts in Kentucky for these (beef and hay) agricultural commodities. This study is important to the general public as well as planners and policy makers. Proper documentation of drought impacts should help identify drought vulnerabilities and result in better risk management and mitigation. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Habitat foraging niche of a High Arctic zooplanktivorous seabird in a changing environment.

    Science.gov (United States)

    Jakubas, Dariusz; Wojczulanis-Jakubas, Katarzyna; Iliszko, Lech M; Strøm, Hallvard; Stempniewicz, Lech

    2017-11-24

    Here, we model current and future distribution of a foraging Arctic endemic species, the little auk (Alle alle), a small zooplanktivorous Arctic seabird. We characterized environmental conditions [sea depth, sea surface temperature (SST), marginal sea ice zone (MIZ)] at foraging positions of GPS-tracked individuals from three breeding colonies in Svalbard: one located at the southern rim of the Arctic zone (hereafter 'boreo-Arctic') and two in the high-Arctic zone on Spitsbergen ('high-Arctic'). The birds from one 'high-Arctic' colony, influenced by cold Arctic water, foraged in the shallow shelf zone near the colony. The birds from remaining colonies foraged in a wider range of depths, in a higher SST zone ('boreo-Arctic') or in the productive but distant MIZ (second 'high-Arctic' colony). Given this flexible foraging behaviour, little auks may be temporarily resilient to moderate climate changes. However, our fuzzy logic models of future distribution under scenarios of 1 °C and 2 °C SST increase predict losses of suitable foraging habitat for the majority of little auk colonies studied. Over longer time scales negative consequences of global warming are inevitable. The actual response of little auks to future environmental conditions will depend on the range of their plasticity and pace of ecosystem changes.

  1. Optimally Frugal Foraging

    OpenAIRE

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

    2017-01-01

    We introduce the \\emph{frugal foraging} model in which a forager performs a discrete-time random walk on a lattice, where each site initially contains $\\mathcal{S}$ food units. The forager metabolizes one unit of food at each step and starves to death when it last ate $\\mathcal{S}$ steps in the past. Whenever the forager decides to eat, it consumes all food at its current site and this site remains empty (no food replenishment). The crucial property of the forager is that it is \\emph{frugal} ...

  2. Espécies forrageiras para produção de leite em solos de várzea Forage species for milk production in lowland soil

    Directory of Open Access Journals (Sweden)

    Domingos Sávio Queiroz

    2012-02-01

    Full Text Available Objetivou-se com este trabalho avaliar a disponibilidade de forragem, a composição morfológica e química do pasto, a capacidade de suporte do pasto e a produção de leite de vacas em três gramíneas forrageiras sob lotação contínua e taxa variável em solo de várzea. O delineamento experimental foi inteiramente casualizado com três tratamentos e três repetições. Os tratamentos constituíram-se das gramíneas Paspalum atratum cv. Pojuca, Brachiaria humidicola cv. Llanero e capim-tangola, híbrido natural de Brachiaria arrecta e Brachiaria mutica. A taxa de lotação foi ajustada para manter a forragem disponível entre 2.000 e 3.000 kg de massa seca por hectare. O período avaliado foi de novembro de 2003 a maio 2004. Não houve diferença significativa entre as espécies quanto à disponibilidade de massa seca de forragem verde, com valor médio de 2.902 kg/ha. O capim-pojuca apresentou 62% de lâminas foliares e 38% de colmo + bainha na massa seca de forragem verde, seguido pelo capim-humidícola com 49 e 51% e o capim-tangola com 18 e 82%, respectivamente. O capim-tangola apresentou teor mais alto de proteína bruta na lâmina foliar (15,41% que os capins humidícola (9,98% e pojuca (8,74% e menores de fibra (FDN e FDA. A produção individual das vacas refletiu o melhor valor alimentício do capim-tangola, cuja média diária (10,27 kg/vaca foi maior que no capim-pojuca (7,80 kg/vaca e semelhante ao obtido com capim-humidícola (9,16 kg/vaca. A produção de leite por área não foi afetada pela gramínea forrageira, com média de 27,8 kg/ha × dia-1, uma vez que a taxa de lotação um pouco mais alta no capim-pojuca, apesar de não apresentar diferença significativa, compensou a menor produção individual das vacas.The objective of this study was to evaluate the forage availability, pasture morphological and chemical composition, pasture carrying capacity and the milk production of cows on three forage grasses under continues

  3. Foraging strategy switch of a top marine predator according to seasonal resource differences

    OpenAIRE

    O'Toole, Malcolm D.; Lea, Mary-Anne; Guinet, Christophe; Schick, Robert; Hindell, Mark A

    2015-01-01

    The spatio-temporal variability in marine resources influences the foraging behavior 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 behavior. Southern elephant seals (Mirounga leonina) have two annual at-sea foraging trips: a 2 month post-breeding foraging trip (Nov–Jan) that coincides with elevated summer productivity; and an 8 month post-molting foraging ...

  4. THE EFFECT OF INCREASING LEVEL OF PALM KERNEL MEAL AND COPRA MEAL ON DIET TO THE MICROBIAL PROTEIN PRODUCTION IN THE RUMEN OF STEERS FED LOW QUALITY FORAGE

    Directory of Open Access Journals (Sweden)

    MARSETYO MARSETYO

    2012-09-01

    Full Text Available SUMMARY The effect of increasing the level of palm kernel meal (PKM and copra meal (CM supplementation on the diet to the microbial crude protein (MCP production, efficiency of microbial protein production (eMCP in the rumen and rumen fluid conditions of Brahman crossbred steers given low quality forage based diet has been studied. Ten steers (243?b6.5 kg were allocated to two supplement types diets (PKM and CM. The experimental design included two incomplete 5x5 Latin Squares, each with three runs, for three months. Each run consisted of a 14 d adaptation and 7 d collection period. Steers received Green panic grass hay ad libitum with one of five levels of PKM or CM (0.00, 0.25, 0.50, 0.75 and 1.00% of body weight (W per day (d. MCP production responded linearly (P<0.05 with increasing PKM or CM intakes. eMCP and rumen NH3-N concentration (taken at 3 and 24 h after feeding responded quadratically (P<0.05 with increasing PKM or CM intakes. It was concluded that supplementation of both PKM and CM up to level of 1.0% W/day resulted in significant increase in MCP production and eMCP in the rumen. These increases were partly due to the increasing of the concentration of rumen NH3-N in the rumen as a result of increasing supplement intakes.

  5. Changes in stable isotope ratios in PDO cheese related to the area of production and green forage availability. The case study of Pecorino Siciliano.

    Science.gov (United States)

    Valenti, Bernardo; Biondi, Luisa; Campidonico, Luca; Bontempo, Luana; Luciano, Giuseppe; Di Paola, Fortunato; Copani, Venera; Ziller, Luca; Camin, Federica

    2017-05-15

    No study has investigated the variations in stable isotope ratios (SIRs) of bioelements within a Protected Designations of Origin (PDO) cheese and few studies have focused on the dietary background of animals. For traceability purposes, it is important to know how and whether these issues affect SIRs in a PDO cheese. Thirty-six Pecorino Siciliano cheese samples were collected in three east-Sicilian areas in seasons in which green herbage was present or absent in the diet of the animals. The determination of C, N and S SIRs was performed using an isotope ratio mass spectrometer coupled with an elemental analyser. The H and O SIRs were measured using an isotope ratio mass spectrometer equipped with a thermal conversion elemental analyser pyrolysis unit. The C, N, H, O and S SIRs measured in defatted cheeses were subjected to a multivariate stepwise discriminant analysis to verify if cheeses could be distinguished based on their geographical origin and on the animals' feeding regimen. Sulfur and nitrogen SIRs allowed the best discrimination among the three areas (97.2% correct classification of the cheeses). The discrimination of the feeding system, to check the presence or not of fresh forage in the diet of the animals, correctly classified 86.1% of the cheeses. The C and O SIRs were the most effective parameters. This study demonstrates that the variability in C, H, O, N and S SIRs can allow discrimination between cheeses produced in a narrow geographical region within a PDO area. This may lead to the search for new tools in authentication studies such as the creation of specific isoscapes. Moreover, this study confirms that SIR determination can also discriminate cheeses obtained from animals fed in stalls from those produced when animals have access to green forage, with benefit in terms of environmental impact, animal welfare and product quality. Copyright © 2017 John Wiley & Sons, Ltd. Copyright © 2017 John Wiley & Sons, Ltd.

  6. Activity cycles and foraging behaviors of free-ranging sidewinder rattlesnakes (Crotalus cerastes): the ontogeny of hunting in a precocial vertebrate.

    Science.gov (United States)

    Clark, Rulon W; Dorr, Scott W; Whitford, Malachi D; Freymiller, Grace A; Putman, Breanna J

    2016-06-01

    Predators often employ a complex series of behaviors to overcome antipredator defenses and effectively capture prey. Although hunting behaviors can improve with age and experience, many precocial species are necessarily effective predators from birth. Additionally, many predators experience innate ontogenetic shifts in predatory strategies as they grow, allowing them to adapt to prey more appropriate for their increased size and energetic needs. Understanding how the relative roles of innate age-specific adaptation and learning have evolved requires information on how predation behavior develops in situ, in free-ranging predators. However, most of the research on the ontogeny of predation behavior is based on laboratory studies of captive animals, largely due to the difficulty of following newborn individuals in nature. Here, we take advantage of the unique tracks left by juveniles of a precocial viperid, the sidewinder rattlesnake (Crotalus cerastes), which we used to follow free-ranging snakes in the field. We recorded details of their ambush hunting behavior, and compared the behaviors of these juveniles to adult snakes that we monitored in the field via radio telemetry. Although juvenile and adult behaviors were similar in most respects, we did find that adults chose more effective ambush sites, which may be due to their increased experience. We also found that juveniles (but typically not adults) perform periodic tail undulations while in ambush, and that juveniles displayed slightly different activity cycles. Both of these latter differences are likely the result of age-specific adaptations for juveniles' greater reliance on lizards versus small mammals as prey. We also compared the general predatory behavior of sidewinders to that of other species in the genus Crotalus. These findings will provide important baseline field information for more detailed empirical research on the ontogeny of predation behavior in precocial vertebrates. Copyright © 2016

  7. Southern Section Interdisciplinary Beef Cattle Symposium: Forage and co-product systems for stockers in the South: have fundamental shifts in markets changed the optimal system?

    Science.gov (United States)

    Rankins, D L; Prevatt, J W

    2013-01-01

    Stockering calves in the southern United States has been an economically viable enterprise for decades. Historically, the system that yielded the best opportunity for profitability was to purchase lightweight calves (130 kg to 220 kg) in autumn, add 100 to 200 kg of BW gain, and sell them in the spring. In most years, the value of the BW gain was worth more than the cost of BW gain in this system. With the exponential price increases in feed, fuel, and fertilizer during 2008 and the significant increase in cattle prices, it is prudent to assess the potential for continued profitability in this segment of the beef industry. Evaluation of 37 grazing experiments indicated that the forage systems most likely to result in inexpensive costs of BW gain for stocker calves involve tall fescue with legumes or ryegrass with small grains. Even with increased input prices, these systems still yield economical BW gain for stocker calves. Likewise, many diets can be blended to produce ADG of 1 kg using co-products that are abundant across the South. With many of these co-products, the most important performance factor in determining their value is G:F. In several experiments, DMI has exceeded 3% of BW in stocker calves, and the resulting G:F has been less than desirable. Several experiments have reported G:F of 0.13 to 0.16, resulting in economical BW gain, whereas some experiments have reported G:F as low as 0.09, which could result in BW gain that costs more to produce than it is worth. From 1979, the value of BW gain for stocker calves in Alabama has averaged US$1.05/kg. However, in the last 3 yr, the value of BW gain has risen to $2.32/kg. Fundamental shifts in feed, fuel, and fertilizer prices experienced in the United States between 2005 and 2010 have markedly changed the amount of capital needed to purchase several hundred stocker calves and to provide adequate feedstuffs for BW gain. However, the value of BW gain associated with producing feeder calves from those stockers

  8. Winter foraging behavior of elk in the shrub-steppe of Washington

    Energy Technology Data Exchange (ETDEWEB)

    McCorquodale, S.M. (Pacific Northwest Lab., Richland, WA (United States))

    1993-01-01

    Numerous models of ungulate foraging behavior have been published, but data on foraging behavior for wild North American ungulates relevant to model testing are scarce. I studied the detailed foraging behavior of elk from autumn through early spring in Washington's shrub-steppe using focal animal sampling and collected corollary data on elk diets, forage quality, and home ranges. I tested the hypotheses that foraging effort is proportional to energetic payoffs determined by the quality and abundance of various forages, and elk home-range size reflects relative foraging movements (i.e., macro and micro movements are related). Elk were mobile foragers during autumn and spring and were relatively sedentary during mid-winter. High mobility was associated with low diet diversity and generally with reduced forage harvesting rates. This mobile foraging occurred during periods of higher quality forage availability. Thus, mobile foraging appeared to reflect increased effort when energetic payoffs of selective foraging were enhanced. Degree of dietary specialization was limited by the relative abundance of preferred forages, being greater when grass quality was high, and less when forb quality was high. Indices of elk movement while foraging were also positively related to home-range size and distance between relocations of radio-collared elk. These data are generally consistent with ungulate foraging model predictions. 34 refs., 4 figs., 2 tabs.

  9. Foraging and recruitment hotspot dynamics for the largest Atlantic loggerhead turtle rookery.

    Science.gov (United States)

    Ceriani, Simona A; Weishampel, John F; Ehrhart, Llewellyn M; Mansfield, Katherine L; Wunder, Michael B

    2017-12-04

    Determining patterns of migratory connectivity for highly-mobile, wide-ranging species, such as sea turtles, is challenging. Here, we combined satellite telemetry and stable isotope analysis to estimate foraging locations for 749 individual loggerheads nesting along the east central Florida (USA) coast, the largest rookery for the Northwest Atlantic population. We aggregated individual results by year, identified seven foraging hotspots and tracked these summaries to describe the dynamics of inter-annual contributions of these geographic areas to this rookery over a nine-year period. Using reproductive information for a subset of turtles (n = 513), we estimated hatchling yields associated with each hotspots. We found considerable inter-annual variability in the relative contribution of foraging areas to the nesting adults. Also reproductive success differed among foraging hotspots; females using southern foraging areas laid nests that produced more offspring in all but one year of the study. These analyses identified two high priority areas for future research and conservation efforts: the continental shelf adjacent to east central Florida and the Great Bahama Bank, which support higher numbers of foraging females that provide higher rates of hatchling production. The implementation of the continuous-surface approach to determine geographic origins of unknown migrants is applicable to other migratory species.

  10. Effects of ewes grazing sulla or ryegrass pasture for different daily durations on forage intake, milk production and fatty acid composition of cheese.

    Science.gov (United States)

    Bonanno, A; Di Grigoli, A; Mazza, F; De Pasquale, C; Giosuè, C; Vitale, F; Alabiso, M

    2016-12-01

    Sulla (Sulla coronarium L.) forage is valued for its positive impact on ruminant production, in part due to its moderate content of condensed tannin (CT). The duration of daily grazing is a factor affecting the feed intake and milk production of ewes. In this study, the effects of grazing sulla pasture compared with annual ryegrass, and the extension of grazing from 8 to 22 h/day, were evaluated with regard to ewe forage intake and milk production, as well as the physicochemical properties and fatty acid (FA) composition of cheese. During 42 days in the spring, 28 ewes of the Comisana breed were divided into four groups (S8, S22, R8 and R22) that grazed sulla (S) or ryegrass (R) for 8 (0800 to 1600 h) or 22 h/day, and received no feeding supplement. In six cheese-making sessions, cheeses were manufactured from the 48 h bulk milk of each group. Compared with ewes grazing ryegrass, those grazing sulla had higher dry matter (DM) intake, intake rate and milk yield, and produced milk that was lower in fat and higher in casein. Ewes grazing for 22 h spent more time eating, which reduced the intake rate, increased DM and nutrient intake and milk yield, and reduced milk fat. Due to the ability of CT to inhibit the complete ruminal biohydrogenation of polyunsaturated fatty acids (PUFA), the FA composition of sulla cheese was more beneficial for consumer health compared with ryegrass cheese, having lower levels of saturated fatty acids and higher levels of PUFA and n-3 FA. The FA profile of S8 cheese was better than that of S22 cheese, as it was higher in branched-chain FA, monounsaturated FA, PUFA, rumenic acid (c9,t11-C18:2), and had a greater health-promoting index. The effect of short grazing time on sulla was attributed to major inhibition of PUFA biohydrogenating ruminal bacteria, presumably stimulated by the higher accumulation of sulla CT in the rumen, which is related to a higher intake rate over a shorter eating time. Thus, grazing sulla improved the performance of

  11. Influence of feeding Mediterranean food industry by-products and forages to Awassi sheep on physicochemical properties of milk, yoghurt and cheese.

    Science.gov (United States)

    Abbeddou, Souheila; Rischkowsky, Barbara; Hilali, Muhi El-Dine; Hess, Hans Dieter; Kreuzer, Michael

    2011-11-01

    Feeding agro-industrial by-products and unconventional forages, rich in potentially anti-nutritional factors, may influence the quality of the raw milk and the dairy products prepared therefrom. The aim of the present study was to determine side-effects on physicochemical properties of milk, yoghurt and cheese of feeding diets where one third were feeds either rich in lipids (tomato pomace and olive cake) or phenols (olive leaves and lentil straw) or electrolytes (Atriplex leaves). The diets, including a control diet, were designed to be isoenergetic and isonitrogenous. They were fed in amounts of 25 kg dry matter/day per head during 50 days to 6×10 multiparous fat-tailed Awassi ewes. Milk samples were analysed for various physicochemical traits and fatty acid composition on days 0, 24, 36 and 48. Three times, milk pooled by group was processed to yoghurt and non-aged farmer-type cheese, which were analysed for their gross and fatty acid composition and texture, and were subjected to sensory evaluation. Feeding olive cake and tomato pomace reduced milk casein, but increased proportions of monounsaturated fatty acids. There were some variations in minerals among test diets but, contrary to expectations, Atriplex did not increase milk sodium. The nutritional composition of yoghurt and cheese was not varied much by the test feeds, except for some changes in fatty acid profile similar to the milk. Yoghurt firmness declined with all test diets, but texture score tended to be lower only for olive cake and leaf diets relative to control. Cheese firmness was increased by feeding the Atriplex leaf and olive cake diets which was also reflected in the texture scores. No off-flavours were reported. Possible reasons for effects on the dairy products are discussed. In conclusion, the feeds investigated had certain effects on the physicochemical properties of dairy products, but these were neither very systematic nor large thus not prohibiting their use in Mediterranean sheep

  12. Genome-Wide Association Mapping of Loci Associated with Plant Growth and Forage Production under Salt Stress in Alfalfa (Medicago sativa L.

    Directory of Open Access Journals (Sweden)

    Xiang-Ping Liu

    2017-05-01

    Full Text Available Salinity tolerance is highly desirable to sustain alfalfa production in marginal lands that have been rendered saline. In this study, we used a diverse panel of 198 alfalfa accessions for mapping loci associated with plant growth and forage production under salt stress using genome-wide association studies (GWAS. The plants were genotyped using genotyping-by-sequencing (GBS. A greenhouse procedure was used for phenotyping four agronomic and physiological traits affected by salt stress, including dry weight (DW, plant height (PH, leaf chlorophyll content (LCC, and stomatal conductance (SC. For each trait, a stress susceptibility index (SSI was used to evaluate plant performance under stressed and non-stressed conditions. Marker-trait association identified a total of 42 markers significantly associated with salt tolerance. They were located on all chromosomes except chromosome 2 based on the alignment of their flanking sequences to the reference genome (Medicago truncatula. Of those identified, 13 were associated with multiple traits. Several loci identified in the present study were also identified in previous reports. BLAST search revealed that 19 putative candidate genes linked to 24 significant markers. Among them, B3 DNA-binding protein, Thiaminepyrophosphokinase and IQ calmodulin-binding motif protein were identified among multiple traits in the present and previous studies. With further investigation, these markers and candidates would be useful for developing markers for marker-assisted selection in breeding programs to improve alfalfa cultivars with enhanced tolerance to salt stress.

  13. Genome-Wide Association Mapping of Loci Associated with Plant Growth and Forage Production under Salt Stress in Alfalfa (Medicago sativa L.).

    Science.gov (United States)

    Liu, Xiang-Ping; Yu, Long-Xi

    2017-01-01

    Salinity tolerance is highly desirable to sustain alfalfa production in marginal lands that have been rendered saline. In this study, we used a diverse panel of 198 alfalfa accessions for mapping loci associated with plant growth and forage production under salt stress using genome-wide association studies (GWAS). The plants were genotyped using genotyping-by-sequencing (GBS). A greenhouse procedure was used for phenotyping four agronomic and physiological traits affected by salt stress, including dry weight (DW), plant height (PH), leaf chlorophyll content (LCC), and stomatal conductance (SC). For each trait, a stress susceptibility index (SSI) was used to evaluate plant performance under stressed and non-stressed conditions. Marker-trait association identified a total of 42 markers significantly associated with salt tolerance. They were located on all chromosomes except chromosome 2 based on the alignment of their flanking sequences to the reference genome (Medicago truncatula). Of those identified, 13 were associated with multiple traits. Several loci identified in the present study were also identified in previous reports. BLAST search revealed that 19 putative candidate genes linked to 24 significant markers. Among them, B3 DNA-binding protein, Thiaminepyrophosphokinase and IQ calmodulin-binding motif protein were identified among multiple traits in the present and previous studies. With further investigation, these markers and candidates would be useful for developing markers for marker-assisted selection in breeding programs to improve alfalfa cultivars with enhanced tolerance to salt stress.

  14. Fishing amplifies forage fish population collapses.

    Science.gov (United States)

    Essington, Timothy E; Moriarty, Pamela E; Froehlich, Halley E; Hodgson, Emma E; Koehn, Laura E; Oken, Kiva L; Siple, Margaret C; Stawitz, Christine C

    2015-05-26

    Forage fish support the largest fisheries in the world but also play key roles in marine food webs by transferring energy from plankton to upper trophic-level predators, such as large fish, seabirds, and marine mammals. Fishing can, thereby, have far reaching consequences on marine food webs unless safeguards are in place to avoid depleting forage fish to dangerously low levels, where dependent predators are most vulnerable. However, disentangling the contributions of fishing vs. natural processes on population dynamics has been difficult because of the sensitivity of these stocks to environmental conditions. Here, we overcome this difficulty by collating population time series for forage fish populations that account for nearly two-thirds of global catch of forage fish to identify the fingerprint of fisheries on their population dynamics. Forage fish population collapses shared a set of common and unique characteristics: high fishing pressure for several years before collapse, a sharp drop in natural population productivity, and a lagged response to reduce fishing pressure. Lagged response to natural productivity declines can sharply amplify the magnitude of naturally occurring population fluctuations. Finally, we show that the magnitude and frequency of collapses are greater than expected from natural productivity characteristics and therefore, likely attributed to fishing. The durations of collapses, however, were not different from those expected based on natural productivity shifts. A risk-based management scheme that reduces fishing when populations become scarce would protect forage fish and their predators from collapse with little effect on long-term average catches.

  15. Determination of Tropical Forage Preferences Using Two Offering Methods in Rabbits

    Directory of Open Access Journals (Sweden)

    A. M. Safwat

    2014-04-01

    Full Text Available Two methods of feed preference trials were compared to evaluate the acceptability of 5 fresh foliages: Leucaena leucocephala, Moringa oleifera, Portulaca oleracea, Guazuma ulmifolia, and Brosimum alicastrum that was included as control. The evaluation included chemical analyses and forage intake by rabbits. The first method was a cafeteria trial; 12 California growing rabbits aged 8 wk, allocated in individual cages, were offered the five forage plants at the same time inside the cage, while in the second trial 60 California growing rabbits aged 8 wk, allocated individually, were randomly distributed into 5 experimental groups (n = 12/group; for each group just one forage species was offered at a time. The testing period for each method lasted for 7 d, preceded by one week of adaptation. The results showed that B. alicastrum and L. lecocephala were the most preferred forages while on the contrary G. ulmifolia was the least preferred one by rabbits. The results also revealed that the CV% value for the 2nd method (16.32%, which the tested forages were presented separately to rabbits, was lower and methodologically more acceptable than such value for the 1st method (34.28%, which all forages were presented together at the same time. It can be concluded that a range of tropical forages were consumed in acceptable quantities by rabbits, suggesting that diets based on such forages with a concentrate supplement could be used successfully for rabbit production. However, growth performance studies are still needed before recommendations could be made on appropriate ration formulations for commercial use.

  16. Determination of Tropical Forage Preferences Using Two Offering Methods in Rabbits

    Science.gov (United States)

    Safwat, A. M.; Sarmiento-Franco, L.; Santos-Ricalde, R. H.; Nieves, D.

    2014-01-01

    Two methods of feed preference trials were compared to evaluate the acceptability of 5 fresh foliages: Leucaena leucocephala, Moringa oleifera, Portulaca oleracea, Guazuma ulmifolia, and Brosimum alicastrum that was included as control. The evaluation included chemical analyses and forage intake by rabbits. The first method was a cafeteria trial; 12 California growing rabbits aged 8 wk, allocated in individual cages, were offered the five forage plants at the same time inside the cage, while in the second trial 60 California growing rabbits aged 8 wk, allocated individually, were randomly distributed into 5 experimental groups (n = 12/group); for each group just one forage species was offered at a time. The testing period for each method lasted for 7 d, preceded by one week of adaptation. The results showed that B. alicastrum and L. lecocephala were the most preferred forages while on the contrary G. ulmifolia was the least preferred one by rabbits. The results also revealed that the CV% value for the 2nd method (16.32%), which the tested forages were presented separately to rabbits, was lower and methodologically more acceptable than such value for the 1st method (34.28%), which all forages were presented together at the same time. It can be concluded that a range of tropical forages were consumed in acceptable quantities by rabbits, suggesting that diets based on such forages with a concentrate supplement could be used successfully for rabbit production. However, growth performance studies are still needed before recommendations could be made on appropriate ration formulations for commercial use. PMID:25049983

  17. Produção e valor nutritivo da forragem de capim-elefante em dois sistemas de produção Forage production and nutritive value of elephantgrass in two production systems

    Directory of Open Access Journals (Sweden)

    Gilmar Roberto Meinerz

    2011-12-01

    Full Text Available Esta pesquisa foi realizada com o objetivo de avaliar a produção e o valor nutritivo da forragem de capim-elefante cultivado em sistemas convencional e agroecológico. No sistema convencional, o capim-elefante foi estabelecido em cultivo exclusivo, em linhas com espaçamento de 1,4 m e, no sistema agroecológico, em linhas afastadas 3 m. Nas entrelinhas, estabeleceu-se azevém no período hibernal para desenvolvimento de espécies de crescimento espontâneo no período estival. Avaliaram-se a massa, a produção e a composição botânica e estrutural da forragem e a carga animal. Amostras de simulação de pastejo foram coletadas para determinação dos teores de proteína bruta e fibra em detergente neutro e da digestibilidade in vitro da matéria seca e matéria orgânica. O delineamento experimental foi o inteiramente casualizado com dois tratamentos (sistemas convencional e agroecológico e duas repetições (piquetes. Valores mais elevados para massa de forragem, produção de forragem, taxa de acúmulo diário e carga animal foram observados no sistema convencional. A relação folha: colmo foi similar entre os sistemas. Valor mais elevado de proteína bruta foi observado no sistema agroecológico. O capim-elefante sob manejo convencional apresenta maior produção de forragem, com menores teores de proteína bruta. O sistema agroecológico apresenta melhor distribuição da produção de forragem no decorrer do ano.The objective of this research was to evaluate elephantgrass pasture on forage production and stocking rate, comparing conventional and agro-ecological production systems. In the conventional system, elephantgrass was established in a singular form, in rows spaced by 1.4 m. In the agro-ecological system, the elephantgrass was established spaced by 3 m and, in the space between lines, ryegrass in cool season was introduced, allowing the development of spontaneous growing species in the warm-season. Herbage mass, forage

  18. Adapting forage to changing needs

    Energy Technology Data Exchange (ETDEWEB)

    Thomas, N.

    1978-09-01

    The Comarca Lagunera in northern Mexico is the principal center of milk production in that country. Water shortages are becoming more critical each year. A main research effort is directed toward increasing the efficiency of use of the available water. Considerable success has been achieved with the introduction of a winter-growing annual, Italian ryegrass (Lolium multiflorum). Its potential yield reaches three-quarters that of alfalfa, but it requires only a quarter to a third of the water. This species has the added advantage that it leaves the land and the water free for summer-growing annuals that are more efficient in their water use than alfalfa. The net result is a forage production sequence that provides more feed at a lower water cost per unit of forage produced.

  19. Forage polyphenol oxidase and ruminant livestock nutrition

    OpenAIRE

    Michael Richard F. Lee

    2014-01-01

    Polyphenol oxidase (PPO) is predominately associated with the detrimental effect of browning fruit and vegetables, however, interest within PPO containing forage crops (crops to be fed to animals) has grown since the browning 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 [feed N into product N (e.g., Milk): NUE] when fed to r...

  20. 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.

  1. Can foraging behavior of Criollo cattle help increase agricultural production and reduce environmental impacts in the arid Southwest?

    Science.gov (United States)

    The Longterm Agroecosystem Research Network (LTAR) was formed to help the nation’s agricultural systems simultaneously increase production and reduce environmental impacts. Eighteen networked sites are conducting a Common Experiment to understand the environmental and economic problems associated wi...

  2. RESEARCHES CONCERNING THE EFFECT OF SOME BIOLOGICALLY-ACTIVE PRODUCTS ON FORAGE BIOMASS YIELD IN SMOOTH BROME

    Directory of Open Access Journals (Sweden)

    I. PET

    2008-05-01

    Full Text Available Vegetal biostimulants are organic products (natural or synthesized that exert upon plant growth an action similar to the phytohormones’ one, when they are applied in small amounts, in certain stages of plant development. Biostimulants change organisms or organs’ development, nutrition or resistance, under various stress conditions, by inducing changes into the vital processes leading to the improvement of crop quality and quantity, to a better and more operative mechanical harvesting and to an improvement in the agricultural products’ preservation. The application of biologically-active products in the smooth brome crop determined growth of the dry matter yield of up to 1.11 t/ha depending on the product used, and the foliar surface index increased in the variants with application of biologically-active products with up to 1.16 m2SA/m2 land, compared to the control variant.

  3. 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

  4. Combined production of free-range pigs and energy crops – animal behaviour and crop damages

    DEFF Research Database (Denmark)

    Horsted, Klaus; Kongsted, Anne Grete; Jørgensen, Uffe

    2012-01-01

    Intensive free-range pig production on open grasslands has disadvantages in that it creates nutrient hotspots and little opportunity for pigs to seek shelter from the sun. Combining a perennial energy crop and pig production might benefit the environment and animal welfare because perennial energy...

  5. The hidden cost of information in collective foraging.

    Science.gov (United States)

    Dechaume-Moncharmont, François-Xavier; Dornhaus, Anna; Houston, Alasdair I; McNamara, John M; Collins, Edmund J; Franks, Nigel R

    2005-08-22

    Many animals nest or roost colonially. At the start of a potential foraging period, they may set out independently or await information from returning foragers. When should such individuals act independently and when should they wait for information? In a social insect colony, for example, information transfer may greatly increase a recruit's probability of finding food, and it is commonly assumed that this will always increase the colony's net energy gain. We test this assumption with a mathematical model. Energy gain by a colony is a function both of the probability of finding food sources and of the duration of their availability. A key factor is the ratio of pro-active foragers to re-active foragers. When leaving the nest, pro-active foragers search for food independently, whereas re-active foragers rely on information from successful foragers to find food. Under certain conditions, the optimum strategy is totally independent (pro-active) foraging because potentially valuable information that re-active foragers may gain from successful foragers is not worth waiting for. This counter-intuitive outcome is remarkably robust over a wide range of parameters. It occurs because food sources are only available for a limited period. Our study emphasizes the importance of time constraints and the analysis of dynamics, not just steady states, to understand social insect foraging.

  6. Experimental warming alters migratory caribou forage quality.

    Science.gov (United States)

    Zamin, Tara J; Côté, Steeve D; Tremblay, Jean-Pierre; Grogan, Paul

    2017-10-01

    Global declines in caribou and reindeer (Rangifer) populations have drawn attention to the myriad of stressors that these Arctic and boreal forest herbivores currently face. Arctic warming has resulted in increased tundra shrub growth and therefore Rangifer forage quantity. However, its effects on forage quality have not yet been addressed although they may be critical to Rangifer body condition and fecundity. We investigated the impact of 8 yrs of summer warming on the quality of forage available to the Bathurst caribou herd using experimental greenhouses (n = 5) located in mesic birch hummock tundra in the central Canadian Low Arctic. Leaf forage quality and digestibility characteristics associated with nutrients (nitrogen and phosphorus), phenolics, and fiber were measured on the deciduous shrub Betula glandulosa (an important Rangifer diet component) at six time points through the growing season, and on five other very common vascular plant and lichen species in late summer. Experimental warming reduced B. glandulosa leaf nitrogen concentrations by ~10% in both late June and mid-July, but not afterwards. It also reduced late summer forage quality of the graminoid Eriophorum vaginatum by increasing phenolic concentrations 38%. Warming had mixed effects on forage quality of the lichen Cetraria cucullata in that it increased nutrient concentrations and tended to decrease fiber contents, but it also increased phenolics. Altogether, these warming-induced changes in forage quality over the growing season, and response differences among species, highlight the importance of Rangifer adaptability in diet selection. Furthermore, the early season reduction in B. glandulosa nitrogen content is a particular concern given the importance of this time for calf growth. Overall, our demonstration of the potential for significant warming impacts on forage quality at critical times for these animals underscores the importance of effective Rangifer range conservation to ensure

  7. The world's biomes and primary production as a triple tragedy of the commons foraging game played among plants.

    Science.gov (United States)

    McNickle, Gordon G; Gonzalez-Meler, Miquel A; Lynch, Douglas J; Baltzer, Jennifer L; Brown, Joel S

    2016-11-16

    Plants appear to produce an excess of leaves, stems and roots beyond what would provide the most efficient harvest of available resources. One way to understand this overproduction of tissues is that excess tissue production provides a competitive advantage. Game theoretic models predict overproduction of all tissues compared with non-game theoretic models because they explicitly account for this indirect competitive benefit. Here, we present a simple game theoretic model of plants simultaneously competing to harvest carbon and nitrogen. In the model, a plant's fitness is influenced by its own leaf, stem and root production, and the tissue production of others, which produces a triple tragedy of the commons. Our model predicts (i) absolute net primary production when compared with two independent global datasets; (ii) the allocation relationships to leaf, stem and root tissues in one dataset; (iii) the global distribution of biome types and the plant functional types found within each biome; and (iv) ecosystem responses to nitrogen or carbon fertilization. Our game theoretic approach removes the need to define allocation or vegetation type a priori but instead lets these emerge from the model as evolutionarily stable strategies. We believe this to be the simplest possible model that can describe plant production. © 2016 The Author(s).

  8. 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

    each one of them. Ryegrass was sowed between rows of EG during the cool-season; red clover was sowed and the forage peanut was preserved on respectively treatments. Holstein cows receiving 5.5kg daily-1 complementary concentrate feed were used. The dry matter daily accumulation rate (DMA,disappearance of forage mass (DFM,dry matter disappeared based on 100kg of live weight (DMD,total dry matter production (TDM, botanical composition and structural component of EG were evaluated. The experimental design used was completely randomized with tree treatments (SF and two replicates (paddocks in incomplete split-plot time (grazing cycles. Nine grazing cycle were performed during the experimental period (341 days. The average values of DMA, DFM, DMD and TDM were 53.16kg ha-1, 36.13%, 2.77kg of dry matter per100kg of liveweight and 17.80t ha-1, respectively. SGS parameter increased significantly over in the PS1. Considering the stocking rate the PS3 showed a better performance.

  9. Effects of short-term variation in forage quality and forage to concentrate ratio on lactating dairy cows.

    Science.gov (United States)

    Yoder, P S; St-Pierre, N R; Daniels, K M; O'Diam, K M; Weiss, W P

    2013-10-01

    Within-farm variation in forage composition can be substantial and potentially costly, and it presents challenges for sampling the forage accurately. We hypothesized that day-to-day variation in forage neutral detergent fiber (FNDF) concentrations and diet variation caused by sampling error would have negative effects on production measures in lactating dairy cows. Twenty-four Holstein cows (73 d in milk) were used in 8 replicated 3 × 3 Latin squares with 21-d periods. Treatments were (1) control (CON), (2) variable (VAR), and (3) overreacting (ORR). On average, over the 21-d period, all 3 treatments were the same [24.7% FNDF and 48.2% forage dry matter (DM) composed of 67% alfalfa silage and 33% grass silage]. The CON treatment was essentially consistent day-to-day in total forage and FNDF concentrations and proportion of alfalfa and grass silages. The VAR treatment changed daily (in a random pattern) in proportion of alfalfa and grass silages fed, which resulted in day-to-day changes in FNDF (range was 21.5 to 28%). The ORR treatment varied in a 5-d cyclic pattern in total forage and FNDF concentrations (26, 24, 28, and 21.5% FNDF). Over the 21 d, ORR (25.1 kg/d) had higher DM intake compared with CON (24.5 kg/d) and VAR (24.3 kg/d). Milk production (42.8 kg/d), milk fat (3.5%), and milk protein (2.8%) were not affected by treatment; however, a treatment × day interaction was observed for milk production. Lower daily milk yields for VAR and ORR compared with CON were rare; they only followed sustained 4- and 5-d periods of feeding higher FNDF diets compared with CON. In contrast, increased daily milk yields for VAR and ORR versus CON were more frequent and followed sustained diet changes of only 2 or 3d. Lipolytic and lipogenic-related enzyme mRNA abundances in subcutaneous adipose tissue were not affected by treatment. Treatment × day interactions were observed for milk fatty acid markers of cellulolytic bacteria (iso-14:0, iso-15:0, iso-16:0) and lipolysis

  10. Predator Foraging in Response to the Mcmurdo Sound Preyscape

    Science.gov (United States)

    Daly, K. L.; Ainley, D. G.; Saenz, B.; Ballard, G.; Kim, S.; Jongsomjit, D.

    2016-02-01

    Growing recent evidence indicates that the Ross Sea, Antarctica, food web is structured as a `wasp-waist' system, in which krill and fish constitute the restriction. The abundance/availability of these prey appears to be affected by top-down predation, and to have only minimal coupling with phytoplankton/primary productivity processes. We investigated this issue further by quantifying prey abundance, depth and distribution along the McMurdo Sound fast-ice edge, using an ROV equipped with acoustic sensors and fluorescence sensors and a CTD equipped with a fluorometer, at the same time that we bio-logged the foraging behavior of Adélie Penguins from an adjacent colony and logged the abundance of trophically competing cetaceans and seals. Early in the study period, concentrations of seals and emperor penguins coincided with a location at which high abundance of an under-ice dwelling fish occurred; these predators disappeared with reduction in that prey's abundance and/or the arrival of seal/penguin-eating killer whales at the fast ice edge. The diet of Adélie penguins changed from 100% krill to 50% krill-fish upon the arrival of minke and fish-eating killer whales. Penguin diving depth did not change, nor did they lengthen foraging range as has been observed in the past upon cetacean arrival. However, the prevalence of the mid-water dwelling forage fish (silverfish) decreased within the penguins' foraging range. Apparently, given the chance penguins and cetaceans appear to have targeted the high-energy dense fish instead of krill, and as a result changed prey availability. Penguin diving depth was just beneath an intense phytoplankton bloom of markedly reduced visibility. Our study brings added support for a food web in which top-down forcing is as important as primary production, having implications for managing fisheries in the region.

  11. Strip-tillage reduces productivity in organically managed grain and forage cropping systems in the Upper Midwest, USA

    Science.gov (United States)

    Globally, tillage is decreasing due to recognized benefits of fuel savings and improved soil health in the absence of disturbance. However, a perceived inability to control weeds effectively and economically hinders no-till adoption in organic production systems in the Upper Midwest. A strip-tilla...

  12. Potential nutritive value of some forage species used as ruminants ...

    African Journals Online (AJOL)

    A study was conducted to determine rumen degradability (in sacco) of dry matter and in vitro gas production of the most important forage species grown in Iran, to compare forage species according to calculated degradation and in vitro gas production parameters, and to establish prediction equations for relative feed value ...

  13. Comparative digestibility by cattle versus sheep: effect of forage quality.

    Science.gov (United States)

    Soto-Navarro, S A; Lopez, R; Sankey, C; Capitan, B M; Holland, B P; Balstad, L A; Krehbiel, C R

    2014-04-01

    The objective was to determine the effect of forage quality on apparent total tract digestibility and ruminal fermentation in cattle versus sheep. Five yearling English crossbred (Hereford × Angus) steers (440.4 ± 35.6 kg of initial BW) and 5 yearling whiteface (Rambouillet × Columbia × Debouillet) wethers (44.4 ± 4.6 kg of initial BW), each fitted with a ruminal cannula, were randomly assigned to 1 of 3 forage sources within ruminant specie, and the study was conducted over 3 periods. For forage source, both animal and period served as the blocking factor with all forage sources represented once within each animal and all forage sources represented at least once within each period. The treatment structure was arranged in a 2 × 3 factorial with ruminant species (2) and forage source (3) as the factors. Forage sources were 1) alfalfa hay (Medicago sativa; 17.5% CP and 34.1% NDF, DM basis), 2) warm-season grass hay mix (Bothriochloa ischaemum and Cynodon dactylon; 7.3% CP and 74.7% NDF, DM basis), and 3) lovegrass hay (Eragrostis curvula; 2.5% CP and 81.9% NDF, DM basis). As a percent of BW, steers and wethers consumed similar (P ≤ 0.06) amounts of forage, and intake was more influenced by forage quality (P forage than by ruminant species (P = 0.07). Steers and wethers had greater (P forages are evaluated. However, sheep are not an adequate model for cattle when low-quality forages are compared because cattle digest low-quality forages to a greater extent than sheep. Expressing digestibility as digestible intake per unit of BW allows for a wider range of forage qualities to be compared when substituting sheep for cattle.

  14. On-farm solid state simultaneous saccharification and fermentation of whole crop forage rice in wrapped round bale for ethanol production.

    Science.gov (United States)

    Horita, Mitsuo; Kitamoto, Hiroko; Kawaide, Tetsuo; Tachibana, Yasuhiro; Shinozaki, Yukiko

    2015-01-01

    In an attempt to reduce environmental loading during ethanol production from cellulosic plant biomass, we have previously proposed an on-site solid state fermentation (SSF) method for producing ethanol from whole crops, which at the same time provides cattle feed without producing wastes. During the ensiling of freshly harvested plant biomass with cellulase and glucoamylase, the added yeast and lactic acid bacteria induced simultaneous saccharification and production of ethanol and lactic acid in hermetically sealed containers on-farm. In a previous study, laboratory-scale SSF (using 250 g of fresh rice crop biomass) yielded 16.9 weight % ethanol in dry matter (DM) after 20 days of incubation. In this study, the fermentation volume was scaled up to a normal-sized round bale and the fermentation process (ethanol concentrations of the products) was monitored. The ethanol produced was recovered and the recovery efficiency was evaluated. SSF tests with forage rice round bales using polyethylene-wrapped whole plant materials (cultivar Leaf Star, average of 125.2 kg dry weight) were monitored in the field without temperature control. They yielded 14.0 weight % ethanol and 2.9 weight % lactic acid in DM after six months of incubation, and the ethanol ratio in the bale remained stable for 14 months after processing. SSF tests with three different rice cultivars were conducted for three years. Ethanol recovery from a fermented whole bale (244 kg fresh matter (FM) containing about 12.4 kg ethanol) by one-step distillation using vacuum distillation equipment yielded 86.3% ethanol collected from distilled solution (107 kg of 10.0 weight % ethanol). In addition, an average of 1.65 kg ethanol in 40.8 kg effluent per bale was recovered. Relative nitrogen content was higher in SSF products than in silage made from the same plant material, indicating that fermentation residue, whose quality is stabilized by the lactic acid produced, can be used as cattle feed. We have

  15. 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

  16. Breeding Better Forages to Help Feed Man and Preserve and Enhance the Environment

    Science.gov (United States)

    Burton, Glenn W.

    1973-01-01

    Discusses the importance of forages in agriculture, and expresses the need for the same high level of technology that is used in the production of corn, wheat, and rice to be applied to forage production. Describes promising forage species, breeding objectives, and breeding procedures used in research. (JR)

  17. Fuzzy approach to business improvement of holding equipment in the conditions of decreased production range

    Directory of Open Access Journals (Sweden)

    Tadić Branko

    2007-01-01

    Full Text Available In recent years, manufacturing industry has been characterized by a decreased production range and a demand for a rapid change of production programs. In such conditions holding equipment costs are considerably larger. In this paper, we review and analyze possible ways of business improvement concerning holding equipment in specific production conditions characterized by the decreased production range and lack of financial sources for applying systems of assembled and disassembled equipment. Classification of elements and group of elements of those systems is performed by applying a new fuzzy ABC method presented in this paper. Selected optimization criteria describe the performance measures of elements and group of elements of assembled and disassembled equipment whereas their relative weights are not the same. It is assumed that the values of imprecise optimization criteria and their relative weights are described by discrete fuzzy numbers. The developed procedure is illustrated by an example with real input data.

  18. Factors influencing local ecological knowledge of forage resources: Ethnobotanical evidence from West Africa's savannas.

    Science.gov (United States)

    Naah, John-Baptist S N; Guuroh, Reginald T

    2017-03-01

    Recording local ecological knowledge (LEK) is a useful approach to understanding interactions of the complex social-ecological systems. In spite of the recent growing interest in LEK studies on the effects of climate and land use changes, livestock mobility decisions and other aspects of agro-pastoral systems, LEK on forage plants has still been vastly under-documented in the West African savannas. Using a study area ranging from northern Ghana to central Burkina Faso, we thus aimed at exploring how aridity and socio-demographic factors drive the distributional patterns of forage-related LEK among its holders. With stratified random sampling, we elicited LEK among 450 informants in 15 villages (seven in Ghana and eight in Burkina Faso) via free list tasks coupled with ethnobotanical walks and direct field observations. We performed generalized linear mixed-effects models (aridity- and ethnicity-based models) and robust model selection procedures. Our findings revealed that LEK for woody and herbaceous forage plants was strongly influenced by the ethnicity-based model, while aridity-based model performed better for LEK on overall forage resources and crop-related forage plants. We also found that climatic aridity had negative effect on the forage-related LEK across gender and age groups, while agro- and floristic diversity had positive effect on the body of LEK. About 135 species belonging to 95 genera and 52 families were cited. Our findings shed more light on how ethnicity and environmental harshness can markedly shape the body of LEK in the face of global climate change. Better understanding of such a place-based knowledge system is relevant for sustainable forage plants utilization and livestock production. Copyright © 2016 Elsevier Ltd. All rights reserved.

  19. Common coastal foraging areas for loggerheads in the Gulf of Mexico: Opportunities for marine conservation

    Science.gov (United States)

    Hart, Kristen M.; Lamont, Margaret M.; Fujisaki, Ikuko; Tucker, Anton D.; Carthy, Raymond R.

    2012-01-01

    Designing conservation strategies that protect wide-ranging marine species is a significant challenge, but integrating regional telemetry datasets and synthesizing modeled movements and behavior offer promise for uncovering distinct at-sea areas that are important habitats for imperiled marine species. Movement paths of 10 satellite-tracked female loggerheads (Caretta caretta) from three separate subpopulations in the Gulf of Mexico, USA, revealed migration to discrete foraging sites in two common areas at-sea in 2008, 2009, and 2010. Foraging sites were 102–904 km away from nesting and tagging sites, and located off southwest Florida and the northern Yucatan Peninsula, Mexico. Within 3–35 days, turtles migrated to foraging sites where they all displayed high site fidelity over time. Core-use foraging areas were 13.0–335.2 km2 in size, in water <50 m deep, within a mean distance to nearest coastline of 58.5 km, and in areas of relatively high net primary productivity. The existence of shared regional foraging sites highlights an opportunity for marine conservation strategies to protect important at-sea habitats for these imperiled marine turtles, in both USA and international waters. Until now, knowledge of important at-sea foraging areas for adult loggerheads in the Gulf of Mexico has been limited. To better understand the spatial distribution of marine turtles that have complex life-histories, we propose further integration of disparate tracking data-sets at the oceanic scale along with modeling of movements to identify critical at-sea foraging habitats where individuals may be resident during non-nesting periods.

  20. Stochasticity in natural forage production affects use of urban areas by black bears: implications to management of human-bear conflicts.

    Science.gov (United States)

    Baruch-Mordo, Sharon; Wilson, Kenneth R; Lewis, David L; Broderick, John; Mao, Julie S; Breck, Stewart W

    2014-01-01

    The rapid expansion of global urban development is increasing opportunities for wildlife to forage and become dependent on anthropogenic resources. Wildlife using urban areas are often perceived dichotomously as urban or not, with some individuals removed in the belief that dependency on anthropogenic resources is irreversible and can lead to increased human-wildlife conflict. For American black bears (Ursus americanus), little is known about the degree of bear urbanization and its ecological mechanisms to guide the management of human-bear conflicts. Using 6 years of GPS location and activity data from bears in Aspen, Colorado, USA, we evaluated the degree of bear urbanization and the factors that best explained its variations. We estimated space use, activity patterns, survival, and reproduction and modeled their relationship with ecological covariates related to bear characteristics and natural food availability. Space use and activity patterns were dependent on natural food availability (good or poor food years), where bears used higher human density areas and became more nocturnal in poor food years. Patterns were reversible, i.e., individuals using urban areas in poor food years used wildland areas in subsequent good food years. While reproductive output was similar across years, survival was lower in poor food years when bears used urban areas to a greater extent. Our findings suggest that bear use of urban areas is reversible and fluctuates with the availability of natural food resources, and that removal of urban individuals in times of food failures has the potential to negatively affect bear populations. Given that under current predictions urbanization is expected to increase by 11% across American black bear range, and that natural food failure years are expected to increase in frequency with global climate change, alternative methods of reducing urban human-bear conflict are required if the goal is to prevent urban areas from becoming population sinks.

  1. Sustainable production and sales of meat from free-range pigs

    DEFF Research Database (Denmark)

    Bredahl, Lone; Andersen, Lone Schreiber

    2002-01-01

    These years, the consumption of pork is not only stagnating in Denmark but also on many other European markets. This coincides with a rise in consumer demand for increased welfare among farm animals. In a project about sustainable production and sales of meat from free-range pigs, guidelines...... are developed on a European level for the production of pork from outdoors production systems, which combine animal welfare with high quality of consumption and high quality of health. In cooperation with colleagues in France, Great Britain and Sweden, MAPP is examining the market potential of this type of meat...

  2. Performance and carcass quality of forage-fed steers as an alternative to concentrate-based beef production

    Directory of Open Access Journals (Sweden)

    Mireia Blanco

    2014-12-01

    Full Text Available This paper studies the performance and carcass quality of Parda de Montaña cattle under different management systems to find alternatives to concentrate feed indoor beef production. Treatments were: i Control, with 8 bulls (216±34.3 kg initial weight; 282±45.6 days fed concentrate and straw ad libitum during winter housing period until reaching 500 kg; ii G-supp, with 8 steers (204±31.2 kg initial weight; 271±47.5 days fed a total mixed ration (TMR (50% alfalfa hay, 10% straw, 40% corn ad libitum during winter housing period (from mid-April steers rotationally grazed on a mountain meadow supplemented with 1.8 kg dry matter corn/d until reaching 500 kg; iii TMR, with 8 steers (200±42.5 kg initial weight; 261±39.0 days managed as G-supp steers until mid-July, when they were housed and fed TMR ad libitum until reaching 500 kg. Control bulls had 45% greater weight gain than TMR and G-supp steers during housing period (P<0.001. In the finishing period, TMR had 31% greater weight gain than steers finished on pasture (P<0.01. At slaughter, Controls were 97-127 days younger than others (P<0.001. Steers finished on TMR had worse conformed carcasses, greater fat and fewer edible meat proportions than G-supp and Control (P<0.01. Total cost of TMR and Gsupp was greater than Control, with a similar income for G-supp and Control. TMR steers were paid less because of their worse carcass quality. Hence, finishing of steers on pasture with a supplement can be a feasible alternative to fattening bulls on concentrates, depending on the relative availability and price of feedstuff.

  3. 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

  4. Adaptive Bacterial Foraging Optimization

    OpenAIRE

    Hanning Chen; Yunlong Zhu; Kunyuan Hu

    2011-01-01

    Bacterial Foraging Optimization (BFO) is a recently developed nature-inspired optimization algorithm, which is based on the foraging behavior of E. coli bacteria. Up to now, BFO has been applied successfully to some engineering problems due to its simplicity and ease of implementation. However, BFO possesses a poor convergence behavior over complex optimization problems as compared to other nature-inspired optimization techniques. This paper first analyzes how ...

  5. Jellyfish, Forage Fish, and the World's Major Fisheries

    National Research Council Canada - National Science Library

    Kelly L. Robinson; James J. Ruzicka; Mary Beth Decker; Richard D. Brodeur; Frank J. Hernandez; Javier Quiñones; E. Marcelo Acha; Shin-ichi Uye; Hermes Mianzan; William M. Graham

    2014-01-01

    ... fishes, seabirds, and marine mammals. Because the plankton production that drives forage fish also drives jellyfish production, these taxa often overlap in space, time, and diet in coastal ecosystem...

  6. Effect of production system (barn and free range) and slaughter age on some production traits of guinea fowl.

    Science.gov (United States)

    Yamak, U S; Sarica, M; Boz, M A; Ucar, A

    2018-01-01

    A total of 200 guinea fowl was reared in either barn or free-range systems and slaughtered at 14, 16, or 18 wk of age in order to determine the effects of production system on live weight, feed consumption, and some carcass and slaughter traits. Production system had a significant effect on live weight until 14 wk of age. Live weights were similar between free-range and indoor production systems at 16 (1,150 g vs. 1,152 g) and 18 (1,196 g vs. 1,203 g) wk of age. Guinea fowl reared in a free-range system consumed more feed (7,693 g vs. 6,983 g), and guinea fowl reared in a barn had better feed conversion ratio (5.80 vs. 6.43) (P slaughter age did not affect the dressing percentage. Guinea fowl reared in a free-range system had significantly less abdominal fat (P < 0.05). © 2017 Poultry Science Association Inc.

  7. Evidence for acoustic communication among bottom foraging humpback whales.

    Science.gov (United States)

    Parks, Susan E; Cusano, Dana A; Stimpert, Alison K; Weinrich, Mason T; Friedlaender, Ari S; Wiley, David N

    2014-12-16

    Humpback whales (Megaptera novaeangliae), a mysticete with a cosmopolitan distribution, demonstrate marked behavioural plasticity. Recent studies show evidence of social learning in the transmission of specific population level traits ranging from complex singing to stereotyped prey capturing behaviour. Humpback whales have been observed to employ group foraging techniques, however details on how individuals coordinate behaviour in these groups is challenging to obtain. This study investigates the role of a novel broadband patterned pulsed sound produced by humpback whales engaged in bottom-feeding behaviours, referred to here as a 'paired burst' sound. Data collected from 56 archival acoustic tag deployments were investigated to determine the functional significance of these signals. Paired burst sound production was associated exclusively with bottom feeding under low-light conditions, predominantly with evidence of associated conspecifics nearby suggesting that the sound likely serves either as a communicative signal to conspecifics, a signal to affect prey behaviour, or possibly both. This study provides additional evidence for individual variation and phenotypic plasticity of foraging behaviours in humpback whales and provides important evidence for the use of acoustic signals among foraging individuals in this species.

  8. Resource heterogeneity and foraging behaviour of cattle across spatial scales

    Directory of Open Access Journals (Sweden)

    Demment Montague W

    2009-04-01

    Full Text Available Abstract Background Understanding the mechanisms that influence grazing selectivity in patchy environments is vital to promote sustainable production and conservation of cultivated and natural grasslands. To better understand how patch size and spatial dynamics influence selectivity in cattle, we examined grazing selectivity under 9 different treatments by offering alfalfa and fescue in patches of 3 sizes spaced with 1, 4, and 8 m between patches along an alley. We hypothesized that (1 selectivity is driven by preference for the forage species that maximizes forage intake over feeding scales ranging from single bites to patches along grazing paths, (2 that increasing patch size enhances selectivity for the preferred species, and that (3 increasing distances between patches restricts selectivity because of the aggregation of scale-specific behaviours across foraging scales. Results Cows preferred and selected alfalfa, the species that yielded greater short-term intake rates (P Conclusion We conclude that patch size and spacing affect components of intake rate and, to a lesser extent, the selectivity of livestock at lower hierarchies of the grazing process, particularly by enticing livestock to make more even use of the available species as patches are spaced further apart. Thus, modifications in the spatial pattern of plant patches along with reductions in the temporal and spatial allocation of grazing may offer opportunities to improve uniformity of grazing by livestock and help sustain biodiversity and stability of plant communities.

  9. Forage yield and quality of kenaf ( Hibiscus cannabinus L.) for ...

    African Journals Online (AJOL)

    This study was carried out to evaluate 40 kenaf accessions for forage yield and quality at Universiti Putra Malaysia in 2009. Forage yield and quality traits were measured at the initial flowering stage. The kenaf accessions showed highly significant variation for most of trait studied. Plant dry matter yield ranged from 5286 kg ...

  10. Foraging of a coastal seabird: flight patterns and movements of ...

    African Journals Online (AJOL)

    Cape gannets Morus capensis are predatory seabirds in the coastal waters of southern Africa where they feed on commercially important fish species. Using a combination of intensive monitoring at nest sites, tracking of radio-tagged birds and diet sampling, we determined the foraging ranges and foraging areas used by ...

  11. The nutritive value of forage sorghum genotypes developed for the ...

    African Journals Online (AJOL)

    Jack Ouda

    for all genotypes after 24 h incubation but Lan-12 had the highest methane production after 72 h incubation. After 24 h and 72 h incubation all the genotypes produced a .... The rumen fluid used was collected from cannulated sheep kept on a maintenance diet with a 60:40 forage to concentrate composition. The forage was ...

  12. Forager abundance and dietary relationships Namib Desert ant ...

    African Journals Online (AJOL)

    Thirteen ant species coexist on a barren gravel plain habitat in the central Namib Desert. Numerical density of foragers of all species fluctuated considerably over a 17-month period. Peaks in abundance correlated to rainfall events and hence primary production pulses. The majority of foragers were noctumal in summer and ...

  13. Environmental and edaphic variables effects on morphogenesis forage production and nutritional quality of an introduced pasture and the natural pastureland of Southern Santa Cruz

    Directory of Open Access Journals (Sweden)

    María Luz Alsina

    2016-12-01

    On the other hand, it was evidenced that the introduced forage species in the pasture, allow efficient use of the available natural resources, obtaining more aerial biomass in relation to the natural pasture and that their availability is strongly influenced by the climatic conditions, which determine the optimum moment of harvesting.

  14. Feasibility of producing a range of food products from a limited range of undifferenitiated major food components

    Science.gov (United States)

    Karel, M.; Kamarei, A. R.

    1984-01-01

    This report reviews current knowledge associated with producing safe, nutritious, and acceptable foods from a limited number of source independent macronutrients. The advantages, and disadvantages, of such an approach for use by space crews are discussed. The production of macronutrients from a variety of sources is covered in detail. The sources analyzed are: wheat, soybeans, algae (3 genera), glycerol, and digested cellulose. Fabrication of food from the above macronutrient sources is discussed and particular attention is addressed to nutrition, acceptability and reliability. The processes and concepts involved in food fabrication and macronutrient production are also considered for utilization in a space environment.

  15. Usefulness of LANDSAT data for monitoring plant development and range conditions in California's annual grassland

    Science.gov (United States)

    Carneggie, D. M.; Degloria, S. D.; Colwell, R. N.

    1977-01-01

    A network of sampling sites throughout the annual grassland region was established to correlate plant growth in stages and forage production to climatic and other environmental factors. Plant growth and range conditions were further related to geographic location and seasonal variations. A sequence of LANDSAT data was obtained covering critical periods in the growth cycle. Data were analyzed by both photointerpretation and computer aided techniques. Image characteristics and spectral reflectance data were then related to forage production, range condition, range site, and changing growth conditions.

  16. Adaptive Bacterial Foraging Optimization

    Directory of Open Access Journals (Sweden)

    Hanning Chen

    2011-01-01

    Full Text Available Bacterial Foraging Optimization (BFO is a recently developed nature-inspired optimization algorithm, which is based on the foraging behavior of E. coli bacteria. Up to now, BFO has been applied successfully to some engineering problems due to its simplicity and ease of implementation. However, BFO possesses a poor convergence behavior over complex optimization problems as compared to other nature-inspired optimization techniques. This paper first analyzes how the run-length unit parameter of BFO controls the exploration of the whole search space and the exploitation of the promising areas. Then it presents a variation on the original BFO, called the adaptive bacterial foraging optimization (ABFO, employing the adaptive foraging strategies to improve the performance of the original BFO. This improvement is achieved by enabling the bacterial foraging algorithm to adjust the run-length unit parameter dynamically during algorithm execution in order to balance the exploration/exploitation tradeoff. The experiments compare the performance of two versions of ABFO with the original BFO, the standard particle swarm optimization (PSO and a real-coded genetic algorithm (GA on four widely-used benchmark functions. The proposed ABFO shows a marked improvement in performance over the original BFO and appears to be comparable with the PSO and GA.

  17. Echolocation click rates and behavior of foraging Hawaiian spinner dolphins

    Science.gov (United States)

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

    2004-05-01

    Groups of spinner dolphins work together to actively aggregate small animals in the deep-scattering layer that serve as their prey. Detailed information on dolphin foraging behavior, obtained with a 200-kHz multibeam sonar (Simrad MS2000), made it possible to correlate echolocation and foraging. Fifty-six groups of spinner dolphins foraging at night within a midwater micronekton sound-scattering layer were observed with the sonar. During sonar surveys, the rates of whistles and echolocation clicks were measured using four hydrophones at 6-m depth intervals. Significant differences in click rates were found between depths and between the different stages of foraging. Groups of foraging dolphins ranged in size from 16 to 28 dolphins. Click rates were not significantly affected by the number of dolphins in a foraging group. Contrary to initial predictions, click rates were relatively low when sonar data indicated that pairs of dolphins were actively feeding. Highest echolocation rates occurred within the scattering layer, during transitions between foraging states. Whistles were only detected when dolphins were not in a foraging formation and when animals were surfacing. This suggests clicks may be used directly or indirectly to cue group movement during foraging.

  18. Matrix product formula for {{U}_{q}}(A_{2}^{(1)}) -zero range process

    Science.gov (United States)

    Kuniba, Atsuo; Okado, Masato

    2017-01-01

    The {{U}q}(An(1)) -zero range processes introduced recently by Mangazeev, Maruyama and the authors are integrable discrete and continuous time Markov processes associated with the stochastic R matrix derived from the well-known {{U}q}(An(1)) quantum R matrix. By constructing a representation of the relevant Zamolodchikov-Faddeev algebra, we present, for n  =  2, a matrix product formula for the steady state probabilities in terms of q-boson operators.

  19. Review: Feeding conserved forage to horses: recent advances and recommendations.

    Science.gov (United States)

    Harris, P A; Ellis, A D; Fradinho, M J; Jansson, A; Julliand, V; Luthersson, N; Santos, A S; Vervuert, I

    2017-06-01

    The horse is a non-ruminant herbivore adapted to eating plant-fibre or forage-based diets. Some horses are stabled for most or the majority of the day with limited or no access to fresh pasture and are fed preserved forage typically as hay or haylage and sometimes silage. This raises questions with respect to the quality and suitability of these preserved forages (considering production, nutritional content, digestibility as well as hygiene) and required quantities. Especially for performance horses, forage is often replaced with energy dense feedstuffs which can result in a reduction in the proportion of the diet that is forage based. This may adversely affect the health, welfare, behaviour and even performance of the horse. In the past 20 years a large body of research work has contributed to a better and deeper understanding of equine forage needs and the physiological and behavioural consequences if these are not met. Recent nutrient requirement systems have incorporated some, but not all, of this new knowledge into their recommendations. This review paper amalgamates recommendations based on the latest understanding in forage feeding for horses, defining forage types and preservation methods, hygienic quality, feed intake behaviour, typical nutrient composition, digestion and digestibility as well as health and performance implications. Based on this, consensual applied recommendations for feeding preserved forages are provided.

  20. Spatial arrangement, population density and legume species effect of yield of forage sorghum-legume intercropping

    Science.gov (United States)

    Sorghum (Sorghum bicolor) is a stress tolerant forage crop grown extensively in the Southern High Plains. However, sorghum forage quality is lower than that of corn. Intercropping sorghum with legumes can improve quality and productivity of forage. However, tall statured sorghum limits the resources...

  1. Factors affecting digestibility of temperate forages from seminatural grasslands : a review

    NARCIS (Netherlands)

    Bruinenberg, M.H.; Valk, H.; Korevaar, H.; Struik, P.C.

    2002-01-01

    To indicate possibilities for the use of forages from seminatural grasslands in ruminant production systems, a literature study to describe the nutritive value of those forages was carried out. In species-rich grasslands, the digestibility of forages is usually lower than the digestibility of

  2. Cooperative Bacterial Foraging Optimization

    Directory of Open Access Journals (Sweden)

    Hanning Chen

    2009-01-01

    Full Text Available Bacterial Foraging Optimization (BFO is a novel optimization algorithm based on the social foraging behavior of E. coli bacteria. This paper presents a variation on the original BFO algorithm, namely, the Cooperative Bacterial Foraging Optimization (CBFO, which significantly improve the original BFO in solving complex optimization problems. This significant improvement is achieved by applying two cooperative approaches to the original BFO, namely, the serial heterogeneous cooperation on the implicit space decomposition level and the serial heterogeneous cooperation on the hybrid space decomposition level. The experiments compare the performance of two CBFO variants with the original BFO, the standard PSO and a real-coded GA on four widely used benchmark functions. The new method shows a marked improvement in performance over the original BFO and appears to be comparable with the PSO and GA.

  3. Assessment of stress tolerance, productivity, and forage quality in T1 transgenic alfalfa co-overexpressing ZxNHX and ZxVP1-1 from Zygophyllum xanthoxylum

    Directory of Open Access Journals (Sweden)

    Peng Kang

    2016-10-01

    Full Text Available Salinization, desertification, and soil nutrient deprivation are threatening the production of alfalfa (Medicago sativa L. in northern China. We have previously generated T0 transgenic alfalfa co-overexpressing Zygophyllum xanthoxylum ZxNHX and ZxVP1-1 genes with enhanced salt and drought tolerance. To further develop this excellent breeding material into the new forage cultivar, stress tolerance, productivity, and forage quality of T1 transgenic alfalfa (GM were assessed in this study. The GM inherited the traits of salt and drought tolerance from T0 generation. Most importantly, co-overexpression of ZxNHX and ZxVP1-1 enhanced the tolerance to Pi deficiency in GM, which was associated with more Pi accumulation in plants. Meanwhile, T1 transgenic alfalfa developed a larger root system with increased root size, root dry weight and root/shoot ratio, which may be one important reason for the improvement of phosphorus nutrition and high biomass accumulation in GM under various conditions. GM also accumulated more crude protein, crude fibre, crude fat, and crude ash than wild-type (WT plants, especially under stress conditions and in the field. More interestingly, the crude fat contents sharply dropped in WT (by 66%-74%, whereas showed no change or decreased less in GM, when subjected to salinity, drought or low-Pi. Our results indicate that T1 transgenic alfalfa co-overexpressing ZxNHX and ZxVP1-1 shows stronger stress tolerance, higher productivity and better forage quality. This study provides a solid foundation for creating the alfalfa cultivars with high yield, good quality and wide adaptability on saline, dry and nutrient-deprived marginal lands of northern China.

  4. Farm Crop Production Technology: Field and Forage Crop and Fruit and Vine Production Options. A Suggested 2-Year Post High School Curriculum.

    Science.gov (United States)

    Division of Vocational and Technical Education, BAVT.

    Prepared by a junior college under contract with the Office of Education, the curriculum materials are designed to assist school administrators, advisory committees, supervisors, and teachers in developing or evaluating postsecondary programs in farm crop production technology. Information was gathered by visits to the important farm regions and…

  5. Comparative Effect of Sole Forage and Mixed Concentrate-Forage ...

    African Journals Online (AJOL)

    The response of weaner rabbits to two dietary treatments, sole forage and mixed concentrate-forage was evaluated in a completely randomized design (CRD) for a trial period of 10 weeks. The concentrate used was poultry growers mash while the forage was Tridax procumbens.Thirty two (32) New Zealand White ...

  6. Produção de forragem de capim-elefante sob clima frio: 2. produção e seletividade animal Elephantgrass forage yield under cold climate conditions: 2. production and animal selectivity

    Directory of Open Access Journals (Sweden)

    Miguel Dall'Agnol

    2005-04-01

    ópolis, Vrukwona, Merckeron Pinda, Turrialba, Porto Rico, Taiwan A-148 and Cameroon, established on 17.5 m² plots in a randomized block design, with three replicates. Each plot consisted of seven lines with 0,50 m interval, using the tree central lines for measurements. These measurements were made on January, March and May of 1985 and 1986, each time the plants height reached 1.5 m. The animal selectivity was done on January and March of 1987, giving scores to the forage after grazing the plots (Botanal method. There was a significant effect of years and cultivars on total forage yield, but the interaction was not significant. On the average, the yield potential ranged from 11 to 21 t DM/ha. There was a 27% reduction on forage yield on the second year (12,116 kg DM/ha of average, compared with the first year (16,662 kg DM/ha. The cultivar Mineiro X-23A presented the highest forage yield and the cultivar Porto Rico showed the highest proportion of leaves and animal selectivity and the cultivar CAC-262 the highest stability, presenting a smaller variance on the two years of evaluations.

  7. Produção de forragem e carga animal de pastagens de Coastcross sobressemeadas com forrageiras de inverno Forage production and stocking rate of Coastcross pastures overseeded with winter grasses

    Directory of Open Access Journals (Sweden)

    Clair Jorge Olivo

    2010-01-01

    Full Text Available O objetivo nesta pesquisa foi avaliar a produção de forragem e a carga animal de quatro pastagens: Coastcross (Cynodon dactylon L. Pers. sobressemeada com azevém (Lolium multiflorum Lam. cv. Comum; Coastcross sobressemeada com azevém e trevo-branco (Trifolium repens L., cv. Yi; azevém e trevo branco; e azevém. O experimento foi realizado no período entre 15 de maio e 24 de outubro de 2006, quando foram realizados cinco ciclos de pastejo. Utilizaram-se vacas da raça Holandesa recebendo concentrado (3,5 kg/dia como suplemento alimentar. Nos períodos pré e pós-pastejo, foram avaliadas a massa de forragem, as composições botânica e estrutural da pastagem e a carga animal. O delineamento experimental foi inteiramente casualizado com quatro tratamentos (pastagens, duas repetições (piquetes e cinco períodos de avaliação (pastejos. Não foram detectadas diferenças entre pastagens para as médias de massa de forragem e carga animal. As pastagens exclusivamente de azevém tiveram maiores produções de lâminas foliares de azevém. As pastagens sobressemeadas apresentaram maior produção de forragem. A sobressemeadura do azevém e do trevo-branco em Coastcross permite estender o período de utilização da pastagem anual e aumenta a produção de forragem.The objective of this research was to evaluate the forage production and stocking rate (SR of four Coastcross (Cynodon dactylon L. Pers. pastures overseeded with ryegrass (Lolium multiflorum Lam. cv. Common; ryegrass plus white clover (Trifolium repens L., cv. Yi over bermudagrass; ryegrass plus white clover and ryegrass. The experiment was carried out from May 15 to October 24, 2006, in five grazing periods. Holstein cows receiving 3.5 kg/daily complementary concentrate feed were used in the evaluation. In the pre and post grazing periods, the forage mass, botanical and structural pasture composition and the stocking rate were assessed. A randomized complete design was used, with

  8. 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...

  9. Performance of free-range chickens reared in production modules enriched with shade net and perches

    Directory of Open Access Journals (Sweden)

    MJB Santos

    2014-03-01

    Full Text Available An experiment was carried out to evaluate the effect of environmental enrichment in a free-range chicken production system on live performance as a function of microclimate, physiological parameters, and performance parameters. Four production modules were divided into four pens with 10 birds each, totaling 60 birds. The following treatments were applied: access to a paddock (TEST, access to a paddock with perches (PER, access to a paddock with artificial shade (SHA, and access to the paddock with perches and artificial shade (PESH. The PESH production module presented the best globe temperature (Tbg,ºC and enthalpy (h, kJ/kg, and thereby, the best thermal environmental conditions, which ensured the longest permanence time of the birds in the paddock. The SHA and PESH modules promoted the lowest respiratory rate and shank and comb temperatures. Live performance was influenced by the presence of environmental enrichment (modules SHA and PESH, with the highest live weight (LW and weight gain (WG and the lowest feed conversion ratio (FCR and metabolizable energy intake (MEI. Parts yield, such as giblets, were not influenced by production modules, except for PESH, which promoted higher offal weight. In general, chickens reared in enriched production modules presented greatest performance and comfort results and were considered close to optimal rearing conditions.

  10. Dynamics of Salmonella Shedding and Welfare of Hens in Free-Range Egg Production Systems

    Science.gov (United States)

    Gole, Vaibhav C.; Woodhouse, Rebecca; Caraguel, Charles; Moyle, Talia; Rault, Jean-Loup; Sexton, Margaret

    2016-01-01

    ABSTRACT The current study investigated the effect of environmental stressors (i.e., weather changes) on Salmonella shedding in free-range production systems and the correlations with behavioral and physiological measures (i.e., fecal glucocorticoid metabolites). This involved longitudinal and point-in-time surveys of Salmonella shedding and environmental contamination on four commercial free-range layer farms. The shedding of Salmonella was variable across free-range farms and in different seasons. There was no significant effect of season on the Salmonella prevalence during this investigation. In this study, the combined Salmonella most probable number (MPN) counts in environmental (including feces, egg belt, dust, nest box, and ramp) samples were highest in samples collected during the summer season (4th sampling, performed in February). The predominant serovars isolated during this study were Salmonella enterica serovar Mbandaka and Salmonella enterica serovar Typhimurium phage types 135 and 135a. These two phage types were involved in several egg product-related Salmonella outbreaks in humans. Multilocus variable-number tandem-repeat analysis (MLVA) results indicated that MLVA types detected from human food poisoning cases exhibited MLVA patterns similar to the strains isolated during this study. All Salmonella isolates (n = 209) were tested for 15 different genes involved in adhesion, invasion, and survival of Salmonella spp. We also observed variations for sopA, ironA, and misL. There were no positive correlations between fecal corticosterone metabolite (FCM) and Salmonella prevalence and/or shedding in feces. Also, there were no positive correlations between Salmonella prevalence and Salmonella count (log MPN) and any of the other welfare parameters. IMPORTANCE In this study, the welfare of laying hens and Salmonella shedding were compared over a prolonged period of time in field conditions. This study investigated the long-term shedding of Salmonella

  11. Dynamics of Salmonella Shedding and Welfare of Hens in Free-Range Egg Production Systems.

    Science.gov (United States)

    Gole, Vaibhav C; Woodhouse, Rebecca; Caraguel, Charles; Moyle, Talia; Rault, Jean-Loup; Sexton, Margaret; Chousalkar, Kapil

    2017-03-01

    The current study investigated the effect of environmental stressors (i.e., weather changes) on Salmonella shedding in free-range production systems and the correlations with behavioral and physiological measures (i.e., fecal glucocorticoid metabolites). This involved longitudinal and point-in-time surveys of Salmonella shedding and environmental contamination on four commercial free-range layer farms. The shedding of Salmonella was variable across free-range farms and in different seasons. There was no significant effect of season on the Salmonella prevalence during this investigation. In this study, the combined Salmonella most probable number (MPN) counts in environmental (including feces, egg belt, dust, nest box, and ramp) samples were highest in samples collected during the summer season (4th sampling, performed in February). The predominant serovars isolated during this study were Salmonella enterica serovar Mbandaka and Salmonella enterica serovar Typhimurium phage types 135 and 135a. These two phage types were involved in several egg product-related Salmonella outbreaks in humans. Multilocus variable-number tandem-repeat analysis (MLVA) results indicated that MLVA types detected from human food poisoning cases exhibited MLVA patterns similar to the strains isolated during this study. All Salmonella isolates ( n = 209) were tested for 15 different genes involved in adhesion, invasion, and survival of Salmonella spp. We also observed variations for sopA , ironA , and misL There were no positive correlations between fecal corticosterone metabolite (FCM) and Salmonella prevalence and/or shedding in feces. Also, there were no positive correlations between Salmonella prevalence and Salmonella count (log MPN) and any of the other welfare parameters. IMPORTANCE In this study, the welfare of laying hens and Salmonella shedding were compared over a prolonged period of time in field conditions. This study investigated the long-term shedding of Salmonella serovars in

  12. Least limiting water range for oil palm production in Amazon region, Brazil

    Directory of Open Access Journals (Sweden)

    Michel Keisuke Sato

    Full Text Available ABSTRACT In areas cultivated with oil palm, typically mechanized field operations using heavy vehicles may negatively affect soil physical properties and productivity. The aim of this study was to evaluate soil physical quality in an area cultivated with oil palm by monitoring the temporal variation of the soil water content and relating it to the critical limits of the least limiting water range. Soil bulk density (Bd, soil penetration resistance (SR, least limiting water range (LLWR, and water stress days (WSD were used to assess soil physical quality in planting rows (PR and the traffic zone (TZ at depths 0-20, 20-40, and 40-60 cm. The Bd was higher and the LLWR was reduced in TZ only at the surface layer. The effect of temporal variation in soil water content on the soil physical quality was higher in TZ, mainly in subsurface layers. Bd and LLWR did not affect the fresh fruit bunch production; however, WSD in TZ at 20-40 and 40-60 cm layers provided evidence of effects of temporal variation of soil water content on oil palm productivity.

  13. Resiliency in forage and grazinglands

    Science.gov (United States)

    This manuscript is a combined effort of the speakers at the 2017 C6 Forage and Grazinglands Division Symposia which was titled “Resiliency in Forage and Grazinglands.” Developing more resilient agroecosystems, including those that produce forage and livestock, will become necessary to maintain agric...

  14. 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…

  15. Sensitivity of physiological emotional measures to odors depends on the product and the pleasantness ranges used

    Directory of Open Access Journals (Sweden)

    Aline Marie Pichon

    2015-12-01

    Full Text Available Emotions are characterized by synchronized changes in several components of an organism. Among them, physiological variations provide energy support for the expression of approach/avoid action tendencies induced by relevant stimuli, while self-reported subjective pleasantness feelings integrate all other emotional components and are plastic.Consequently, emotional responses evoked by odors should be highly differentiated when they are linked to different functions of olfaction (e.g., avoiding environmental hazards. As this differentiation has been observed for contrasted odors (very pleasant or unpleasant, we questioned whether subjective and physiological emotional response indicators could still disentangle subtle affective variations when no clear functional distinction is made (mildly pleasant or unpleasant fragrances. Here, we compared the sensitivity of behavioral and physiological (respiration, skin conductance, facial electromyography (EMG, and heart rate indicators in differentiating odor-elicited emotions in two situations: when a wide range of odor families was presented (e.g., fruity, animal, covering different functional meanings; or in response to a restricted range of products in one particular family (fragrances. Results show clear differences in physiological indicators to odors that display a wide range of reported pleasantness, but these differences almost entirely vanish when fragrances are used even though their subjective pleasantness still differed. Taken together, these results provide valuable information concerning the ability of classic verbal and psychophysiological measures to investigate subtle differences in emotional reactions to a restricted range of similar olfactory stimuli.

  16. FFT-based Kronecker product approximation to micromagnetic long-range interactions

    CERN Document Server

    Exl, Lukas; Mauser, Norbert J; Schrefl, Thomas; Stimming, Hans Peter; Suess, Dieter

    2012-01-01

    We derive a Kronecker product approximation for the micromagnetic long range interactions in a collocation framework by means of separable sinc quadrature. Evaluation of this operator for structured tensors (Canonical format, Tucker format, Tensor Trains) scales below linear in the volume size. Based on efficient usage of FFT for structured tensors, we are able to accelerate computations to quasi linear complexity in the number of collocation points used in one dimension. Quadratic convergence of the underlying collocation scheme as well as exponential convergence in the separation rank of the approximations is proved. Numerical experiments on accuracy and complexity confirm the theoretical results.

  17. Quantitative enzymatic production of sialylated galactooligosaccharides with an engineered sialidase from Trypanosoma rangeli

    DEFF Research Database (Denmark)

    Zeuner, Birgitte; Holck, Jesper; Perna, Valentina

    2016-01-01

    molecules, providing the novelty point that GOS molecules are sialylated independently of their size by Tr13. Using CGMP, GOS, and Tr13, the production of gram-scale quantities of sialyl-GOS was achieved in 20L volume reactions. Compared to the benchmark transsialidase from pathogenic Trypanosoma cruzi...... be produced from κ(kappa)-casein glycomacropeptide (CGMP), a sialylated side stream component from cheese-making, by sialidase-catalyzed transsialylation. Using a rationally designed mutant of the sialidase from Trypanosoma rangeli, Tr13, with enhanced transsialylation activity, six different GOS preparations...

  18. Características morfológicas, estruturais e produtividade do capim-braquiária e do amendoim forrageiro submetidos ao sombreamento Morphological and structural characteristics and productivity of Brachiaria grass and forage peanut submitted to shading

    Directory of Open Access Journals (Sweden)

    Kátia Fernanda Gobbi

    2009-09-01

    Full Text Available As características morfológicas, estruturais e a produção de matéria seca (PMS do capim-braquiária (Brachiaria decumbens, cv. Basilisk e do amendoim forrageiro (Arachis pintoi, cv. Amarillo foram avaliadas em resposta a três níveis de sombreamento artificial (0, 50 e 70%. Utilizou-se o delineamento em blocos casualizados, com três repetições. Foram realizados três e dois cortes, respectivamente, para avaliação do capim-braquiária e do amendoim forrageiro. O amendoim forrageiro apresentou redução significativa na produção de matéria seca com o sombreamento apenas no segundo corte. A produção de matéria seca no capim-braquiária diminuiu linearmente nos dois primeiros cortes. O sombreamento crescente estimulou o aumento da altura média do dossel e do comprimento de pecíolos, colmos e lâminas foliares em todos os cortes das espécies avaliadas. O sombreamento promoveu diminuição linear da densidade populacional de perfilhos no dossel de braquiária em todos os cortes. O peso médio dos perfilhos, no entanto, só foi afetado no terceiro corte, quando aumentou de forma linear de acordo com os níveis de sombreamento. A relação folha:caule da gramínea e da leguminosa não foi afetada pelo sombreamento. A área foliar específica, a área foliar por folíolo e a área foliar por perfilho aumentaram significativamente com o aumento dos níveis de sombreamento. O índice de área foliar (IAF reduziu de forma linear no segundo corte com o sombreamento do amendoim forrageiro e do capim-braquiária. O amendoim forrageiro e o capim-braquiária são forrageiras com bom potencial para avaliação e uso em sistemas silvipastoris com transmissão luminosa em torno de 50% da radiação fotossinteticamente ativa.The morphological and structural characteristics and dry matter production of signalgrass (Brachiaria decumbens, cv. Basilisk and forage peanut (Arachis pintoi, cv. Amarillo were evaluated in response to different shading

  19. [Optimized Spectral Indices Based Estimation of Forage Grass Biomass].

    Science.gov (United States)

    An, Hai-bo; Li, Fei; Zhao, Meng-li; Liu, Ya-jun

    2015-11-01

    As an important indicator of forage production, aboveground biomass will directly illustrate the growth of forage grass. Therefore, Real-time monitoring biomass of forage grass play a crucial role in performing suitable grazing and management in artificial and natural grassland. However, traditional sampling and measuring are time-consuming and labor-intensive. Recently, development of hyperspectral remote sensing provides the feasibility in timely and nondestructive deriving biomass of forage grass. In the present study, the main objectives were to explore the robustness of published and optimized spectral indices in estimating biomass of forage grass in natural and artificial pasture. The natural pasture with four grazing density (control, light grazing, moderate grazing and high grazing) was designed in desert steppe, and different forage cultivars with different N rate were conducted in artificial forage fields in Inner Mongolia. The canopy reflectance and biomass in each plot were measured during critical stages. The result showed that, due to the influence in canopy structure and biomass, the canopy reflectance have a great difference in different type of forage grass. The best performing spectral index varied in different species of forage grass with different treatments (R² = 0.00-0.69). The predictive ability of spectral indices decreased under low biomass of desert steppe, while red band based spectral indices lost sensitivity under moderate-high biomass of forage maize. When band combinations of simple ratio and normalized difference spectral indices were optimized in combined datasets of natural and artificial grassland, optimized spectral indices significant increased predictive ability and the model between biomass and optimized spectral indices had the highest R² (R² = 0.72) compared to published spectral indices. Sensitive analysis further confirmed that the optimized index had the lowest noise equivalent and were the best performing index in

  20. Foraging area fidelity for Kemp's ridleys in the Gulf of Mexico.

    Science.gov (United States)

    Shaver, Donna J; Hart, Kristen M; Fujisaki, Ikuko; Rubio, Cynthia; Sartain, Autumn R; Peña, Jaime; Burchfield, Patrick M; Gamez, Daniel Gomez; Ortiz, Jaime

    2013-07-01

    For many marine species, locations of key foraging areas are not well defined. We used satellite telemetry and switching state-space modeling (SSM) to identify distinct foraging areas used by Kemp's ridley turtles (Lepidochelys kempii) tagged after nesting during 1998-2011 at Padre Island National Seashore, Texas, USA (PAIS; N = 22), and Rancho Nuevo, Tamaulipas, Mexico (RN; N = 9). Overall, turtles traveled a mean distance of 793.1 km (±347.8 SD) to foraging sites, where 24 of 31 turtles showed foraging area fidelity (FAF) over time (N = 22 in USA, N = 2 in Mexico). Multiple turtles foraged along their migratory route, prior to arrival at their "final" foraging sites. We identified new foraging "hotspots" where adult female Kemp's ridley turtles spent 44% of their time during tracking (i.e., 2641/6009 tracking days in foraging mode). Nearshore Gulf of Mexico waters served as foraging habitat for all turtles tracked in this study; final foraging sites were located in water surface temperature, bathymetry, and net primary production were significant predictors of sites where turtles spent large numbers of days in foraging mode. Spatial similarity of particular foraging sites selected by different turtles over the 13-year tracking period indicates that these areas represent critical foraging habitat, particularly in waters off Louisiana. Furthermore, the wide distribution of foraging sites indicates that a foraging corridor exists for Kemp's ridleys in the Gulf. Our results highlight the need for further study of environmental and bathymetric components of foraging sites and prey resources contained therein, as well as international cooperation to protect essential at-sea foraging habitats for this imperiled species.

  1. Foraging area fidelity for Kemp's ridleys in the Gulf of Mexico

    Science.gov (United States)

    Shaver, Donna J.; Hart, Kristen M.; Fujisaki, Ikuko; Rubio, Cynthia; Sartain-Iverson, Autumn R.; Peña, Jaime; Burchfield, Patrick M.; Gamez, Daniel Gomez; Ortiz, Jaime

    2013-01-01

    For many marine species, locations of key foraging areas are not well defined. We used satellite telemetry and switching state-space modeling (SSM) to identify distinct foraging areas used by Kemp's ridley turtles (Lepidochelys kempii) tagged after nesting during 1998–2011 at Padre Island National Seashore, Texas, USA (PAIS; N = 22), and Rancho Nuevo, Tamaulipas, Mexico (RN; N = 9). Overall, turtles traveled a mean distance of 793.1 km (±347.8 SD) to foraging sites, where 24 of 31 turtles showed foraging area fidelity (FAF) over time (N = 22 in USA, N = 2 in Mexico). Multiple turtles foraged along their migratory route, prior to arrival at their "final" foraging sites. We identified new foraging "hotspots" where adult female Kemp's ridley turtles spent 44% of their time during tracking (i.e., 2641/6009 tracking days in foraging mode). Nearshore Gulf of Mexico waters served as foraging habitat for all turtles tracked in this study; final foraging sites were located in water <68 m deep and a mean distance of 33.2 km (±25.3 SD) from the nearest mainland coast. Distance to release site, distance to mainland shore, annual mean sea surface temperature, bathymetry, and net primary production were significant predictors of sites where turtles spent large numbers of days in foraging mode. Spatial similarity of particular foraging sites selected by different turtles over the 13-year tracking period indicates that these areas represent critical foraging habitat, particularly in waters off Louisiana. Furthermore, the wide distribution of foraging sites indicates that a foraging corridor exists for Kemp's ridleys in the Gulf. Our results highlight the need for further study of environmental and bathymetric components of foraging sites and prey resources contained therein, as well as international cooperation to protect essential at-sea foraging habitats for this imperiled species.

  2. Respuesta productiva de conejos alimentados con forraje verde hidropónico de avena, como reemplazo parcial de concentrado comercial Productive response of rabbits fed with green hydroponic oats forage as partial replacement of commercial concentrate

    Directory of Open Access Journals (Sweden)

    Francisco Fabián Fuentes Carmona

    2011-04-01

    Full Text Available La respuesta productiva de conejos raza californiana alimentados con forraje verde hidropónico (FVH de avena como reemplazo parcial de concentrado comercial (CC, fue evaluada en condiciones de desierto en el norte de Chile. Se establecieron cinco tratamientos de alimentación, equivalentes a 0, 25, 50, 75 y 100% de reemplazo de la dieta diaria con FVH, el cual fue cosechado y utilizado directamente diez días después de la siembra. Cuarenta y cinco conejos destetados a los 31 días fueron evaluados en un diseño completamente al azar hasta alcanzar un peso de sacrificio de 2 kg de peso vivo. La calidad del FVH de avena fue considerada como buena, presentando similar valor nutritivo que el CC. Las variables evaluadas y sus respectivos rangos fueron: consumo de materia seca promedio (59.17 - 104.73 g/día, ganancia de peso vivo promedio (16.35 - 29.10 g/animal por día, conversión alimenticia promedio (3.31 - 3.93 kg MS/kg PV, tiempo de peso vivo a sacrificio (53 - 91 días, peso vivo final (1430 - 2044 g/animal, peso de la canal (1235 - 1385 g/animal y rendimiento de la canal (59.19 - 62.25%. El reemplazo de hasta 50% de la dieta base con FVH de avena no afectó significativamente (P The productive response of Californian rabbits fed with hydroponic green oats forage (HGOF as a partial replacement of commercial concentrate (CC was evaluated under desert conditions in northern Chile. Five treatments were established as follow: 0, 25, 50, 75 and 100% replacement of daily diet with HGOF, which was harvested and used directly at 10 days after sowing. Forty-five rabbits weaned at 31 days were evaluated in a completely randomized design until slaughter weight of 2.0 kg. HGOF quality was considered as good, presenting similar nutritional value to CC. The variables assessed and range values were: average dry matter intake (59.17-104.73 g/d, average weight gain (16.35-29.10 g/ rabbit for day, feed conversion average (3.31-3.93 kg DM/ kg LW, time of

  3. PLANT RAW MATERIAL EXTRACTS AS COMPONENTS OF COSMETIC PRODUCTS AND FORMULATIONS FOR TOPICAL ADMINISTRATION: THE PRODUCT RANGE, THE PRODUCTION CHARACTERISTICS (REVIEW)

    OpenAIRE

    S. B. Evseeva; B. B. Sysuev

    2016-01-01

    In contemporary pharmaceutical practice extracts are used as a separate cosmetic product and as an intermediate for external medicinal forms (ointments, gels, liniments) and cosmetic forms. Their range is highly diverse.The aim is an overview of the scientific and technical information concerning plant  raw materials extracts using in the external drug and cosmetic products.Methods. To describe the range of extracts proposed for external use the analysis of the proposals of Russian and foreig...

  4. Source levels of foraging humpback whale calls.

    Science.gov (United States)

    Fournet, Michelle E H; Matthews, Leanna P; Gabriele, Christine M; Mellinger, David K; Klinck, Holger

    2018-02-01

    Humpback whales produce a wide range of low- to mid-frequency vocalizations throughout their migratory range. Non-song "calls" dominate this species' vocal repertoire while on high-latitude foraging grounds. The source levels of 426 humpback whale calls in four vocal classes were estimated using a four-element planar array deployed in Glacier Bay National Park and Preserve, Southeast Alaska. There was no significant difference in source levels between humpback whale vocal classes. The mean call source level was 137 dB RMS re 1 μPa @ 1 m in the bandwidth of the call (range 113-157 dB RMS re 1 μPa @ 1 m), where bandwidth is defined as the frequency range from the lowest to the highest frequency component of the call. These values represent a robust estimate of humpback whale source levels on foraging grounds and should append earlier estimates.

  5. Passive FOG IMU for short-range missile application: from qualification toward series production

    Science.gov (United States)

    Trommer, Gert F.; Mueller, R.; Opitz, S.

    1996-11-01

    An inertial measurement unit (IMU) with angular rate, angular increment and linear acceleration measurement systems for short range missile application is described. It consists of a three axis fiber optic gyroscope (FOG) cluster, three linear vibrating beam accelerometers and an electronics device for signal evaluation and data transmission via a serial transputer link. The FOG cluster is realized by means of a passive all-fiber open loop configuration. Due to the inherent optical phase shift of 3 by 3 couplers, completely passive operation near the quadrature point is achieved without the need for a non- reciprocal optical phase modulation in the fiber loop. Basing on that concept more than 50 rugged IMUs have been built for implementation into a short range air to air missile. Verification tests for flight clearance with stresses simulating air carriage and missile free flight environments have been computed. The operation under extreme vibration and shock environments without the use of vibration isolator fixings due to very tight requirements on data time delay has been demonstrated. The first telemetered missile firings have been performed successfully. The line- setup for large quantity series production is progressing. The implementation of the workstations for the integration of the IMU is finished. The production equipment for calibration and acceptance testing of IMUs in parallel allowing for a rate of more than 150 unit per month has been installed and will be operational in autumn this year.

  6. 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

  7. The effects of kale (Brassica oleracea ssp. acephala), basil (Ocimum basilicum) and thyme (Thymus vulgaris) as forage material in organic egg production on egg quality

    DEFF Research Database (Denmark)

    Hammershøj, Marianne; Steenfeldt, Sanna

    2012-01-01

    /kg basil, 3) maize silage incl. 30 g/kg basil, 4) maize silage incl. 15 g/kg thyme, or 5) fresh kale leaves. Each was supplied to three replicates of 20 hens. A total of 300 hens was used. 3. Feed intake, forage intake and laying rate did not differ with treatment, but egg weight and egg mass produced...... with the thyme treatment. By sensory evaluation, the kale treatment resulted in eggs with less sulphur aroma, higher yolk colour score, and more sweet and less watery albumen taste. Furthermore, the eggs of the kale treatment had significantly higher lutein and -carotene content. Also, violaxanthin, an orange...

  8. Prevalence of gastrointestinal helminth infections in free-range laying hens under mountain farming production conditions.

    Science.gov (United States)

    Wuthijaree, K; Lambertz, C; Gauly, M

    2017-10-27

    1. A cross-sectional study was conducted from September 2015 to July 2016 in South Tyrol, Northern Italy to examine the prevalence of gastrointestinal helminths in free-range laying hens under mountain farming production conditions. 2. A total of 280 laying hens from 14 free-range mountain farms (4 organic, 10 conventional) were randomly collected at the end of the laying period. Faecal samples were taken to analyse faecal egg counts (FEC) and faecal oocyst counts (FOC). The gastrointestinal tracts were removed post mortem and examined for the presence of helminths. 3. In faeces, FEC values averaged 258 eggs per g of faeces, which were dominated by Ascaridia galli and Heterakis gallinarum. Mean FOC was 80 oocysts/g. In the gastrointestinal tract, at least one nematode species was found in 99.3% of the examined hens. H. gallinarum was the most prevalent nematode (95.7%), followed by Capillaria spp. (66.8%) and A. galli (63.6%). Thirty per cent of the chickens were infected with cestodes (tapeworms). Correlation coefficients between worm counts of H. gallinarum, Capillaria spp. and A. galli ranged from 0.41 to 0.51. 5. The helminth prevalence did not differ between conventional and organic farms, whereas total worm burden was higher in organic compared with conventional farms (318.9 vs. 112.0). Prevalence and infection intensity did not differ between farms that used anthelmintic treatments and those that did not. 6. In conclusion, free-range laying hens under the studied mountain farming conditions are at high risk of nematode infection, especially in organic systems. The vast majority of hens are subclinical infected with at least one helminth species.

  9. Feasibility study of wood stork foraging habitat mapping using landsat multispectral data

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, J.R.; Hodgson, M.E.; Coulter, M.; Mackey, H.E. Jr.

    1986-01-01

    The wood stork is a large wading bird which forages in shallow wetlands up to 70 kilometers from the colony. Landsat data were evaluated to determine if remote sensing data were suitable for locating and estimating the extent of potential foraging habitat for this species over such a large range. Thematic Mapper data of north-central Georgia and the Savannah River floodplain in South Carolina were obtained May 5, 1984. Spectral signatures from known foraging sites near a colony in Georgia were identified. Computer clustering techniques were used to identify and map shallow water and marsh wetland foraging habitats. Foraging acreages were computed, and maps of the locations of candidate foraging sites were produced for a 1520-square-kilometer area. Remote sensing appears to provide a feasible method of evaluating the regional wetland foraging habitat available to this wide-ranging species.

  10. Yield and nutritive quality of forage legumes on reclaimed surface mined land

    Energy Technology Data Exchange (ETDEWEB)

    Ditsch, D.C.; Collins, M. [University of Kentucky, Quicksand, KY (United States). Robinson Experiment Station

    1998-07-01

    Legumes are important in the long-term nitrogen economy of surface mined lands and for establishing and maintaining quality livestock forage. Little information is available to reclamation specialists for use in selection of forage legume species based on productivity potential, persistence and nutritive quality for livestock. A study was initiated at two sites in the Appalachian coal fields of Kentucky to evaluate monocultures of alfalfa (Medicago sativa L.), red clover (Trifolium pratense L.) and birdsfoot trefoil (Lotus corniculatus L.) under management regimes suitable for livestock production. Legumes were harvested at the early bloom stage throughout the growing season for dry matter (DM) yield determination. Forage quality was determined by measuring crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), cellulose (CEL) and acid detergent lignin (ADL). High DM yields were produced by all species during the first production season (range 6.2-9.2 Mg ha{sup -1}) but yields of all species declined rapidly by year three. Birdsfoot trefoil demonstrated slightly greater drought tolerance during mid-season (July/August) than alfalfa and red clover. With the exception of site {number_sign}1 in 1992 (4 harvests), no more than 3 harvests were made during a single growing season. Crude protein concentration of these forage legumes was found to be within the range commonly measured on undisturbed lands. However, high NDF and ADF values were observed above those reported by others for the same species. These results indicate that it may be difficult to maintain a high level of productivity throughout the five-year bonding period under hay management. Management practices such as summer stockpiling may be necessary to compensate for the rapid and wide fluctuations in DM yield and quality due to low water-holding capacity of mine spoils. 15 refs., 2 figs., 7 tabs.

  11. Produção e composição química da palma forrageira micropropagada in vitro Production and chemical composition of forage palm micropropagated in vitro

    Directory of Open Access Journals (Sweden)

    Luiz Barreto de Morais Neto

    2010-12-01

    Full Text Available Avaliou-se a relação entre o tamanho das plântulas, a produção e a composição química da palma forrageira cv. Gigante micropropagada in vitro. O experimento foi realizado no setor de Forragicultura do Departamento de Zootecnia, UFC, em Fortaleza-Ceará, em solo com textura arenosa. Utilizou-se o delineamento experimental em blocos ao acaso, com três tratamentos (mudas com 10-20, 20-30 e maiores que 30cm e quatro repetições. O espaçamento utilizado foi o semi-adensado (1,0m entre fileiras e 0,5m entre plantas, com parcelas experimentais de área igual a 3,5 x 1,5m, com quatro plantas úteis por parcelas. Após dois anos do plantio, as plantas foram cortadas à altura do terço inferior da raquete secundária, onde foram avaliadas a produção de cladódios e a composição química da palma forrageira. Foram retiradas amostras, levadas ao Laboratório de Nutrição Animal para realização das análises. No tratamento com plântulas maiores que 30cm houve uma produção de 102,6t/ha de massa verde, que diferiu a um nível de significância de 5%, dos tratamentos 10-20cm e 20-30cm, com valores de 53,4 e 53,2t/ha, respectivamente. Não houve diferença significativa ao nível de 5% de significância pelo teste t de Student para a composição química. Conclui-se que as mudas de palma forrageira devem ser transplantadas com tamanho superior a 30cm, contudo o tamanho da muda não interferiu na composição química da palma forrageira.We evaluated the relationship between the size of seedlings, production and chemical composition of forage palm cv. Giant micropropagated in vitro. The experiment was conducted at the Forage Department of Animal Science, UFC, Fortaleza, Ceará, in soils with sand texture. We used the experimental design of randomized blocks with three treatments (seedlings with 10-20, 20-30 and bigger than 30cm and four replications. The spacing used was a semi-dense (1.0m between rows and 0.5m between plants, and

  12. Primary production in an impounded baldcypress swamp (Taxodium distichum) at the northern limit of the range

    Science.gov (United States)

    Middleton, B.A.; McKee, K.L.

    2005-01-01

    The ability of baldcypress (Taxodium distichum)swamps to maintain themselves near the northern limit of their range depends on their levels of production, which is not only are response to climate but also to local environmental factors(e.g., impoundment). We asked if primary production was reduced under impounded conditions and if species' responses to impoundment were individualistic or more generalized. To examine long-term production trends in a permanently impounded baldcypress swamp, a 6-year study of leaf litterfall was conducted in Buttonland Swamp, Illinois, which had been impounded for 10 years before the beginning of the study. Buttonland Swamp is at the northern boundary of the baldcypress swamp region along the Cache River, Illinois, in the Mississippi River Alluvial Valley of the United States. When the litter production of impounded sites was compared to those with natural hydrology in the same region, impounded sites had about half of the total litterfall of natural sites. Overall, leaf litterfall rates declined during the study(201 vs. 113 gm-2 yr-1), but the pattern was negatively correlated with water depth, which explained 97% of the variation in the data. Along the transect with the lowest mean minimum water depth(<0.5 cm), leaf litterfall decreased linearly over 6 years from 377 to 154gm-2 yr-1. Total leaf litterfall rates were lower at the other three depths(5, 43, and 49 cm mean minimum water depths)and remained below 200 gm-2 yr -1 throughout the study. Acer saccharinum, Nyssa aquatica, and Salix nigra were most responsible for the decline in total leaf litterfall. Amounts of leaf litterfall of T. distichum and Liquidambar styraciflua also generally decreased, while that of Cephalanthus occidentalis increased overtime. Because species' responses to environmental factors such as impoundment are individualistic, models should be based on the responses of individual species, rather than on communities. Our study further suggests that the

  13. Nitrogen regulation of algal biomass, productivity, and composition in shallow mountain lakes, Snowy Range, Wyoming, USA

    Science.gov (United States)

    Nydick, Koren R.; Lafrancois, Brenda Moraska; Baron, Jill S.; Johnson, Brett M.

    2004-01-01

    We investigated the effects of increased nitrate (NO3), alone and in combination with phosphorus (P), on phytoplankton, epilithon, and epipelon in shallow lakes of the Snowy Range, Wyoming, using two enclosure experiments during early and late summer. Phytoplankton responded strongly to N and N + P, but not to P, with increased cell density, chlorophyll a, and photosynthesis and shifts in composition from chrysophytes to cyanophytes, chlorophytes, and diatoms. Zooplankton density and biomass were unaltered despite the additional phytoplankton stock, probably as the result of poor food quality. In the late summer, algae on tiles responded to N and N + P additions with greater chlorophyll a and increases in cyanophyte and chlorophyte density. Algae on sediment dominated whole-enclosure algal biomass but were spatially variable and responded insignificantly to nutrients. Consequently, N controlled productivity and community composition of phytoplankton and algae on hard substrates but had less impact on ecosystem algal biomass because of the large pool of nutrient-sufficient sediment algae. Phytoplankton were more photosynthetically efficient than the benthos, however, such that primary productivity did shift more toward the water column.

  14. Dynamics of r.f. production of Stellarator plasmas in the ion cyclotron range of frequency

    Energy Technology Data Exchange (ETDEWEB)

    Moiseenko, V.E. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Center; Lysoivan, A.I. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Center; Kasilov, S.V. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Center; Plyusnin, V.V. [Kharkov Inst. of Phys. and Tech. (Ukraine). Nat. Center

    1995-01-01

    The present study investigated numerically the process of r.f. production of plasma in the URAGAN-3M torsatron in the frequency range below the ion cyclotron frequency ({omega}<{omega}{sub ci}). The dynamics of r.f. plasma build-up at the stages of neutral gas burnout and plasma heating were studied using a zero-dimensional transport code, in which the plasma confinement law was determined by large helical device scaling. Two models for input r.f. power were used. In the first case, the r.f. power absorbed by the electrons was computed by a one-dimensional r.f. code solving Maxwell`s boundary problem equations. The mechanisms of electron heating through direct excitation of the slow wave (SW) by antennae as well as the conversion of fast wave (FW) into SW in the vicinity of Alfven resonance (scenario of Alfven heating) were taken into account in the computations. In the second case, an `ideal` model of r.f. power deposition onto the electrons as a linear function of plasma density was employed. A noticeable difference in plasma production dynamics computed for these two cases was found. Better agreement with experimental data obtained from the URAGAN-3M torsatron was found for the first case resulting from combination of the one-dimensional r.f. and zero-dimensional transport codes. ((orig.)).

  15. Field energetics and foraging mode of Kalahari lacertid lizards

    Energy Technology Data Exchange (ETDEWEB)

    Nagy, K.A.; Huey, R.B.; Bennett, A.F.

    1984-04-01

    The authors examined the energetic costs associated with foraging mode in the widely foraging lizard Eremias lugubris (mean mass 3.83 g) and the sit-and-wait lizard Eremias lineoocellata (3.27 g). These lizards are broadly sympatric in the Kalahari desert. The widely foraging species had significantly higher field metabolic rates (800 vs. 544 J/d, as measured with doubly labeled water), feeding rates (metabolizable energy of 1165 vs. 739 J/d), production rates (365 vs. 195 J/d) and water influx rates (0.285 vs. 0.156 mL/d). Measurements were made before the reproductive season began; there were no significant differences in these measures between sexes within either species. Resting metabolic rates (measured as O/sub 2/ consumed) were similar at 37/sup 0/C (0.240 vs. 0.252 mL g/sup -1/ H/sup -1/) and 26/sup 0/ (0.094 vs. 0.103 mL g/sup -1/ h/sup -1/), the field active and nocturnal burrow temperatures respectively, of both species. Field metabolic rates, on a 24-h basis, were 3.1 x resting in E. lugubris and 2.2 x resting in E. lineoocellata. Energy expenditures during the activity period were 12.0 x resting in the wide forager and 2.8 x resting in the sit-and-wait predator. Foraging efficiency (metabolizable energy gained while foraging/total energy spent while foraging) was higher in the wide forager (2.0 than in the sit-and-wait predator. The wide forager grew nearly twice as fast as did the sit-and-wait predator during this study. On an annual basis, variation in food availability or differences in predation rate may alter the relative fitness of these foraging modes.

  16. 5 CFR 532.253 - Special rates or rate ranges for leader, supervisory, and production facilitating positions.

    Science.gov (United States)

    2010-01-01

    ... to the same occupational series and title, that lead, supervise, or perform production facilitating..., supervisory, and production facilitating positions. 532.253 Section 532.253 Administrative Personnel OFFICE OF....253 Special rates or rate ranges for leader, supervisory, and production facilitating positions. (a...

  17. 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...

  18. Determination of Nutrient Contents and In vitro Gas Production Values of Some Legume Forages Grown in the Harran Plain Saline Soils.

    Science.gov (United States)

    Boga, M; Yurtseven, S; Kilic, U; Aydemir, S; Polat, T

    2014-06-01

    The aim of this study was to determine the nutritive value of some legume species in salt-affected soils of South-East Anatolian region using chemical composition and in vitro gas production kinetics. In this study, Lotus corniculatus, Trifolium alexandrinum, Medicago sativa were sown and tested in four different locations. A 3 by 4 factorial design with 3 legume species and 4 salt levels (non salty electrical conductivity (EC)ECECEC) was used in the study. Results indicated that salinity and plants had no significant effect on ash and ether extract. Dry matter (DM), acid detergent fiber, digestible dry matter, dry matter intake (DMI) were affected by plant, salinity and plant×salinity interaction. On the other hand neutral detergent fiber, relative feed value (RFV), and DMI were affected by salinity and plant×salinity interaction. Mineral contents were affected by plant species, salinity and salinity×plants interactions. In vitro gas production, their kinetics and estimated parameters such as were not affected by salinity whereas the gas production up to 48 h, organic matter digestibility, metabolizable energy (ME), and net energy lactation (NEL) were affected by plant and plant×salt interaction. Generally RFVs of all species ranged from 120 to 210 and were quite satisfactory in salty conditions. Current results show that the feed value of Medicago sativa is higher compared to Lotus corniculatus and Trifolium alexandrinum.

  19. Balancing organization and flexibility in foraging dynamics.

    Science.gov (United States)

    Tabone, Michaelangelo; Ermentrout, Bard; Doiron, Brent

    2010-10-07

    Proper pattern organization and reorganization are central problems facing many biological networks which thrive in fluctuating environments. However, in many cases the mechanisms that organize system activity oppose those that support behavioral flexibility. Thus, a balance between pattern organization and pattern flexibility is critically important for overall biological fitness. We study this balance in the foraging strategies of ant colonies exploiting food in dynamic environments. We present discrete time and space simulations of colony activity that uses a pheromone-based recruitment strategy biasing foraging towards a food source. After food relocation, the pheromone must evaporate sufficiently before foraging can shift colony attention to a new food source. The amount of food consumed within the dynamic environment depends non-monotonically on the pheromone evaporation time constant-with maximal consumption occurring at a time constant which balances trail formation and trail flexibility. A deterministic, 'mean field' model of pheromone and foragers on trails mimics our colony simulations. This reduced framework captures the essence of the flexibility-organization balance, and relates optimal pheromone evaporation to the timescale of the dynamic environment. We expect that the principles exposed in our study will generalize and motivate novel analysis across a broad range systems biology. 2010 Elsevier Ltd. All rights reserved.

  20. GPS tracking devices reveal foraging strategies of black-legged kittiwakes

    Science.gov (United States)

    Kotzerka, Jana; Garthe, Stefan; Hatch, Scott A.

    2010-01-01

    The Black-legged Kittiwake Rissa tridactyla is the most abundant gull species in the world, but some populations have declined in recent years, apparently due to food shortage. Kittiwakes are surface feeders and thus can compensate for low food availability only by increasing their foraging range and/or devoting more time to foraging. The species is widely studied in many respects, but long-distance foraging and the limitations of conventional radio telemetry have kept its foraging behavior largely out of view. The development of Global Positioning System (GPS) loggers is advancing rapidly. With devices as small as 8 g now available, it is possible to use this technology for tracking relatively small species of oceanic birds like kittiwakes. Here we present the first results of GPS telemetry applied to Black-legged Kittiwakes in 2007 in the North Pacific. All but one individual foraged in the neritic zone north of the island. Three birds performed foraging trips only close to the colony (within 13 km), while six birds had foraging ranges averaging about 40 km. The maximum foraging range was 59 km, and the maximum distance traveled was 165 km. Maximum trip duration was 17 h (mean 8 h). An apparently bimodal distribution of foraging ranges affords new insight on the variable foraging behaviour of Black-legged Kittiwakes. Our successful deployment of GPS loggers on kittiwakes holds much promise for telemetry studies on many other bird species of similar size and provides an incentive for applying this new approach in future studies.

  1. Produção, caracterização nutricional e fermentativa de silagens de sorgo forrageiro e sorgo duplo propósito = Production, fermentation and nutritional characteristics of forage and double purpose sorghum silages

    Directory of Open Access Journals (Sweden)

    Fernando Reimann Skonieski

    2010-01-01

    Full Text Available Objetivou-se com o trabalho avaliar a produtividade de cinco híbridos de sorgo forrageiro e cinco híbridos de sorgo duplo propósito, bem como caracterizar os parâmetros fermentativos e nutricionais das silagens confeccionadas a partir desses materiais. O delineamento experimental foi de blocos ao acaso, com três repetições portratamento. Os resultados foram submetidos à análise de variância e as médias dos híbridos, submetidas ao estudo de contrastes ortogonais, sorgo forrageiro “versus” sorgo duplo propósito. Todos os híbridos apresentam condições de ensilagem por meio da avaliação dos parâmetros fermentativos. As silagens elaboradas a partir de sorgoforrageiro apresentam menor teor de MS (33,01% e pH (3,86, contra 38,32% de MS e 3,97 de pH das silagens de sorgo duplo propósito. Silagens de sorgo forrageiro e sorgo duplo propósito apresentam valor nutricional semelhantes, porém, as silagens de sorgo duplo propósito apresentam maior teor de CEL (25,30% e K (1,16%. Os híbridos desorgo forrageiro produziram em média 17.527 kg ha-1 de MS, superior à produtividade média dos híbridos de sorgo duplo propósito de 13.006 kg ha-1 de MS.This work was set out to evaluate productivity, nutritional and fermentation characteristics of different sorghum cultivar silages. The experimental design was randomized blocks with three replications. The results were submitted to ANOVA and mean values of each cultivar were used for an orthogonal contrasts study (forage sorghum vs. double purpose sorghum silages. Results of fermentative characteristics showed that all cultivars presented potential forensilage. Double purpose sorghum silages showed higher (p < 0.05 dry matter content (38.32% when compared to forage sorghum silage (33.01%, as well as for pH values. Likewise, double purpose sorghum silages showed significant, increased levels of CEL (25.30% and K (1.16%. Forage sorghum cultivars showed higher (p < 0.05 productivity (17527 kg

  2. Alfalfa (Medicago Sativa L As A Promising Forage In Indonesia

    Directory of Open Access Journals (Sweden)

    Sajimin

    2011-06-01

    Full Text Available Alfalfa (Medicago sativa L or Lucerne is a perennial herbaceous legume with superior forage quality. It is the most important forage crop in the world and it was the first domesticated forage crop. Alfalfa is able to fix nitrogen from the air through a symbiotic relationship with Rhizobium bacteria with N production 7.85 – 10.37 g/m2. Its rooting system can reach 4.5 m that allows it to escape drought. Forage production can reach 15.48 tons of dry matter per ha/year and containing 18.0 – 29.1 % crude protein. Plants can live 3 to 12 years depending on climatic conditions and crop varieties. However, alfalfa is not a tropical plant, thus it has not been widely cultivated in Indonesia. The problem of alfalfa cultivation are high pest attacks and competition with weeds. Therefore, alfalfa cultivation requires attention and good management to obtain optimum yield.

  3. The Dynamics of Foraging Ants

    Science.gov (United States)

    Baxter, G. William

    2009-03-01

    We experimentally study the foraging of small black ants, Formicinae lasius flavus, in order to describe their foraging behavior mathematically. Individual ants are allowed to forage on a two-dimensional surface in the absence of any food sources. The position of the ant as a function of time is determined using a high-resolution digital camera. Analysis of the average square displacements of many ants suggests that the foraging strategy is a non-reversing random walk. Moreover, the ants do not retrace their steps to return home but instead continue the random walk until it brings them back near their starting point.

  4. 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.

  5. Simulation modeling to understand how selective foraging by beaver can drive the structure and function of a willow community

    Science.gov (United States)

    Peinetti, H.R.; Baker, B.W.; Coughenour, M.B.

    2009-01-01

    Beaver-willow (Castor-Salix) communities are a unique and vital component of healthy wetlands throughout the Holarctic region. Beaver selectively forage willow to provide fresh food, stored winter food, and construction material. The effects of this complex foraging behavior on the structure and function of willow communities is poorly understood. Simulation modeling may help ecologists understand these complex interactions. In this study, a modified version of the SAVANNA ecosystem model was developed to better understand how beaver foraging affects the structure and function of a willow community in a simulated riparian ecosystem in Rocky Mountain National Park, Colorado (RMNP). The model represents willow in terms of plant and stem dynamics and beaver foraging in terms of the quantity and quality of stems cut to meet the energetic and life history requirements of beaver. Given a site where all stems were equally available, the model suggested a simulated beaver family of 2 adults, 2 yearlings, and 2 kits required a minimum of 4 ha of willow (containing about10 stems m-2) to persist in a steady-state condition. Beaver created a willow community where the annual net primary productivity (ANPP) was 2 times higher and plant architecture was more diverse than the willow community without beaver. Beaver foraging created a plant architecture dominated by medium size willow plants, which likely explains how beaver can increase ANPP. Long-term simulations suggested that woody biomass stabilized at similar values even though availability differed greatly at initial condition. Simulations also suggested that willow ANPP increased across a range of beaver densities until beaver became food limited. Thus, selective foraging by beaver increased productivity, decreased biomass, and increased structural heterogeneity in a simulated willow community.

  6. Forest response to elevated CO2 is conserved across a broad range of productivity

    Science.gov (United States)

    Norby, Richard J.; DeLucia, Evan H.; Gielen, Birgit; Calfapietra, Carlo; Giardina, Christian P.; King, John S.; Ledford, Joanne; McCarthy, Heather R.; Moore, David J. P.; Ceulemans, Reinhart; De Angelis, Paolo; Finzi, Adrien C.; Karnosky, David F.; Kubiske, Mark E.; Lukac, Martin; Pregitzer, Kurt S.; Scarascia-Mugnozza, Giuseppe E.; Schlesinger, William H.; Oren, Ram

    2005-01-01

    Climate change predictions derived from coupled carbon-climate models are highly dependent on assumptions about feedbacks between the biosphere and atmosphere. One critical feedback occurs if C uptake by the biosphere increases in response to the fossil-fuel driven increase in atmospheric [CO2] (“CO2 fertilization”), thereby slowing the rate of increase in atmospheric [CO2]. Carbon exchanges between the terrestrial biosphere and atmosphere are often first represented in models as net primary productivity (NPP). However, the contribution of CO2 fertilization to the future global C cycle has been uncertain, especially in forest ecosystems that dominate global NPP, and models that include a feedback between terrestrial biosphere metabolism and atmospheric [CO2] are poorly constrained by experimental evidence. We analyzed the response of NPP to elevated CO2 (≈550 ppm) in four free-air CO2 enrichment experiments in forest stands. We show that the response of forest NPP to elevated [CO2] is highly conserved across a broad range of productivity, with a stimulation at the median of 23 ± 2%. At low leaf area indices, a large portion of the response was attributable to increased light absorption, but as leaf area indices increased, the response to elevated [CO2] was wholly caused by increased light-use efficiency. The surprising consistency of response across diverse sites provides a benchmark to evaluate predictions of ecosystem and global models and allows us now to focus on unresolved questions about carbon partitioning and retention, and spatial variation in NPP response caused by availability of other growth limiting resources. PMID:16330779

  7. Resource heterogeneity and foraging behaviour of cattle across spatial scales.

    Science.gov (United States)

    Utsumi, Santiago A; Cangiano, Carlos A; Galli, Julio R; McEachern, Mary B; Demment, Montague W; Laca, Emilio A

    2009-04-24

    Understanding the mechanisms that influence grazing selectivity in patchy environments is vital to promote sustainable production and conservation of cultivated and natural grasslands. To better understand how patch size and spatial dynamics influence selectivity in cattle, we examined grazing selectivity under 9 different treatments by offering alfalfa and fescue in patches of 3 sizes spaced with 1, 4, and 8 m between patches along an alley. We hypothesized that (1) selectivity is driven by preference for the forage species that maximizes forage intake over feeding scales ranging from single bites to patches along grazing paths, (2) that increasing patch size enhances selectivity for the preferred species, and that (3) increasing distances between patches restricts selectivity because of the aggregation of scale-specific behaviours across foraging scales. Cows preferred and selected alfalfa, the species that yielded greater short-term intake rates (P < 0.0001) and greater daily intake potential. Selectivity was not affected by patch arrangement, but it was scale dependent. Selectivity tended to emerge at the scale of feeding stations and became strongly significant at the bite scale, because of differences in bite mass between plant species. Greater distance between patches resulted in longer patch residence time and faster speed of travel but lower overall intake rate, consistent with maximization of intake rate. Larger patches resulted in greater residence time and higher intake rate. We conclude that patch size and spacing affect components of intake rate and, to a lesser extent, the selectivity of livestock at lower hierarchies of the grazing process, particularly by enticing livestock to make more even use of the available species as patches are spaced further apart. Thus, modifications in the spatial pattern of plant patches along with reductions in the temporal and spatial allocation of grazing may offer opportunities to improve uniformity of grazing by

  8. Visualising and animating visual information foraging in context

    OpenAIRE

    Chen, C.; Cribbin, T

    2001-01-01

    Optimal information foraging provides a potentially useful framework for modelling, analysing, and interpreting search strategies of users through a spatial-semantic interface. Improving the understanding of behavioural patterns of users in such environments has implications for the design and refinement of a range of user interfaces. In this article, we outline the role of optimal information foraging in the study of visual information retrieval and how one may use visualisation and animatio...

  9. 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 (CTmax). 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.

  10. Foraging niche segregation in Malaysian babblers (Family: Timaliidae).

    Science.gov (United States)

    Mansor, Mohammad Saiful; Ramli, Rosli

    2017-01-01

    Tropical rainforests are considered as hotspots for bird diversity, yet little is known about the system that upholds the coexistence of species. Differences in body size that are associated with foraging strategies and spatial distribution are believed to promote the coexistence of closely related species by reducing competition. However, the fact that many babbler species do not differ significantly in their morphology has challenged this view. We studied the foraging ecology of nine sympatric babbler species (i.e., Pellorneum capistratum, P. bicolor, P. malaccense, Malacopteron cinereum, M. magnum, Stachyris nigriceps, S. nigricollis, S. maculata, and Cyanoderma erythropterum) in the Krau Wildlife Reserve in Peninsular Malaysia. We investigated; i) how these babblers forage in the wild and use vegetation to obtain food, and ii) how these trophically similar species differ in spatial distribution and foraging tactics. Results indicated that most babblers foraged predominantly on aerial leaf litter and used gleaning manoeuvre in intermediate-density foliage but exhibited wide ranges of vertical strata usage, thus reducing interspecific competition. The principal component analysis indicated that two components, i.e., foraging height and substrate are important as mechanisms to allow the coexistence of sympatric babblers. The present findings revealed that these bird species have unique foraging niches that are distinct from each other, and this may apply to other insectivorous birds inhabiting tropical forests. This suggests that niche separation does occur among coexisting birds, thus following Gause' law of competitive exclusion, which states two species occupying the same niche will not stably coexist.

  11. Product range of two-stroke engines on motorcycles. Produktpalette von Zweitaktmotoren in motorisierten Zweiraedern

    Energy Technology Data Exchange (ETDEWEB)

    Scheibe, J. (IFA-Kombinat fuer Zweiradfahrzeuge, Suhl (Germany, F.R.))

    1990-01-01

    At present there are five different types of engines in the production range: 50 cc engines for lawnmowers and vehicles for the disabled; 50/70 cc engines for 'Mokicks', rollers, light motorcycles (mopeds), garden equipment; 125/150 cc engines for motorcycles; 250 cc engines for motorcycles. Data on standardized design principles are given, together with extensive component sketches, for these series of engines. They extent to air-cooling while in motion, aluminium cylinders, reverse flushing, crankshafts in roller bearings, multi-disc oil bath clutch, 4 or 5 speed gearbox, mixture lubrication and a 12 V electrical supply. The carburettor used in 2-stroke engines of motorcycles has a separate cold start and tickover system. The harmful emission from the motorcycles is appreciably below the limits of EEC regulation 40. In order to be able to comply with the legal limits for the exhaust gas components CO, CH and NO{sub x} in Switzerland and Austria, these 2-stroke engined motorcycles must, however, be provided with an oxidation catalyst. (HWJ).

  12. Expanding the range of auxetic polymeric products using a novel melt-spinning route

    Science.gov (United States)

    Ravirala, N.; Alderson, A.; Alderson, K. L.; Davies, P. J.

    2005-03-01

    The first auxetic fibre was successfully produced in polypropylene using a novel melt-spinning route. These fibres were extruded at 159 °C with a screw speed 10 rpm (1.05 rad s-1) and 2 mpm (0.03 m s-1) take-up speed. Characterisation of these fibres involved optical techniques (videoextensometry) to measure the strains along both the length and the width simultaneously during deformation. The unique processing route has now been developed to expand the range of auxetic extruded polymeric products. We report here that auxetic polypropylene films have been developed, and auxetic polyester and polyamide fibres have now been produced. We also report the development of a simple rough particle model to predict auxetic behaviour that may be applicable to the developed fibres and films. Finally, a review of some potential applications for auxetic fibres and films will be presented. These include as reinforcements in composites, anchoring devices, smart bandages for health-care, breathable packaging and tear resistant films.

  13. Excitation of Lamb waves over a large frequency-thickness product range for corrosion detection

    Science.gov (United States)

    Zeng, Liang; Luo, Zhi; Lin, Jing; Hua, Jiadong

    2017-09-01

    For corrosion detection, it is often desirable that a Lamb wave mode is highly sensitive to surface thinning and enjoys some degree of mode purity at a particular frequency. In view of this, this paper aims to generate a variety of Lamb wave modes over broad frequency bands to ensure an abundant supply of candidates for corrosion detection, and further, establish a strategy to find appropriate operation points efficiently and effectively. Firstly, a short-duration laser pulse is applied to generate Lamb waves over a large frequency-thickness product range. The selection of symmetric modes or anti-symmetric modes is obtained by addition or subtraction of signals captured by two identical transducers which are symmetrically coupled on both sides of the plate. Subsequently, the S0 mode at a non-dispersive frequency bandwidth is employed to improve the accuracy of the transmitter-receiver distance. Based on those, three selection criteria including mode separability, amplitude ratio and corrosion sensitivity, are presented to efficiently determine the suitable operation points (i.e., mode types and frequencies). The experimental results show that the simulated corrosion could be correctly detected and accurately localized at the chosen modes and frequencies.

  14. Effects of forage polyphenols on chemistry of ruminant excreta and fate of nitrogen in soils and the environment

    Science.gov (United States)

    The chemical composition of forages consumed by ruminants affects forage intake, digestion, meat and milk production, as well as manure chemistry and manure impacts on the environment. The digestion of forages by ruminants and the decomposition of organic materials applied to soils are governed by s...

  15. Choice and foraging

    OpenAIRE

    Abarca, Nureya; Fantino, Edmund

    1982-01-01

    In Experiment 1, six naive pigeons were trained on a foraging schedule characterized by different states beginning with a search state in which completion of a fixed-interval on a white key led to a choice state. In the choice state the subject could, by appropriate responding on a fixed ratio of three, either accept or reject the schedule of reinforcement that was offered (either a variable-interval five-second or a variable-interval 20-second). If the subject accepted the schedule, it enter...

  16. Foraging Online Social Networks

    OpenAIRE

    Koot, Gijs; Huis in ’t Veld, Mirjam; Hendricksen, Joost; Kaptein, Rianne; Vries, Arnout; van den Broek, Egon; den Hengst, M; Israël, M; Zeng, D.; Veenman, C.; Wang, A.

    2014-01-01

    A concise and practical introduction is given on Online Social Networks (OSN) and their application in law enforcement, including a brief survey of related work. Subsequently, a tool is introduced that can be used to search OSN in order to generate user profiles. Both its architecture and processing pipeline are described. This tool is meant as a flexible framework that supports manual foraging (and not replaces it). As such, we aim to bridge science’s state-of-the-art and current security of...

  17. Effects of Forage Sources on Rumen Fermentation Characteristics, Performance, and Microbial Protein Synthesis in Midlactation Cows

    Directory of Open Access Journals (Sweden)

    Jun Xu

    2014-05-01

    Full Text Available Eight multiparous Holstein cows (632±12 kg BW; 135±16 DIM were used in a replicated 4×4 Latin square design to evaluate the effects of forage sources on rumen fermentation characteristics, performance, and microbial protein (MCP synthesis. The forage portion of the diets contained alfalfa hay (AH, oat hay (OH, Leymus chinensis (LC, or rice straw (RS as the primary source of fiber. Diets were isonitrogenous and isocaloric, and cows were fed four corn silages based total mixed rations with equivalent nonfiber carbohydrate (NFC and forage neutral detergent fiber (NDF. Dry matter intake was not affected by the source of dietary forages, ranging from 18.83 to 19.20 kg/d, consequently, milk yield was similar among diets. Because of the numerical differences in milk fat and milk protein concentrations, 4% FCM and ECM yields were unchanged (p>0.05. Mean rumen pH, NH3-N content, and concentrations of volatile fatty acids in the rumen fluid were not affected by the treatments (p>0.05. Dietary treatments did not affect the total tract apparent digestibility of dry matter, organic matter, and crude protein (p>0.05; however, digestibility of NDF and acid detergent fiber in RS diet was higher compared with AH, OH, and LC diets (p<0.05. Total purine derivative excretion was higher in cows fed AH, OH, and LC diets compared with those fed RS diet (p<0.05, consequently, estimated MCP synthesis was 124.35 g/d higher in cows fed AH diet compared with those fed RS diet (p<0.05. The results indicated that cows fed AH, OH, LC, and RS diets with an equivalent forage NDF and NFC have no unfavourable effect on the ruminal fermentation and productive parameters.

  18. Influence of fresh forage-based diets and αs₁-casein (CSN1S1) genotype on nutrient intake and productive, metabolic, and hormonal responses in milking goats.

    Science.gov (United States)

    Bonanno, A; Di Grigoli, A; Di Trana, A; Di Gregorio, P; Tornambè, G; Bellina, V; Claps, S; Maggio, G; Todaro, M

    2013-04-01

    Polymorphism at the αS1-casein locus (CSN1S1) in goats influences several milk production traits. Milk from goats carrying strong alleles, which are associated with high αS1-casein (αS1-CN) synthesis, has higher fat and casein contents, longer coagulation time and higher curd firmness than milk from goats with weak alleles linked to low αS1-CN content. Nutrition also affects these milk properties; therefore, it is important to better understand the interaction between dietary characteristics and the CSN1S1 genotype in goats. This study aimed to investigate the effect of fresh forage based diet or energy supplement on feeding behavior, milk production, and metabolic and hormonal parameters of Girgentana goats with different genotypes at CSN1S1 loci. From a group of goats genotyped by PCR at the DNA level, 12 were selected because they had the same genotype for αS2-CN, β-CN, and κ-CN but a different genotype for αS1-CN: 6 were homozygous for strong alleles at the CSN1S1 loci (AA) and 6 were heterozygous for a weak allele (AF). Goats of each genotype were allocated to 3 subgroups and fed 3 diets ad libitum in a 3×3 Latin square design. The diets were sulla (Hedysarum coronarium L.) fresh forage, sulla fresh forage plus 800 g/d of barley meal (SFB), and mixed hay plus 800 g/d of barley meal (MHB). Diet had a stronger effect than CSN1S1 genotype. The SFB diet led to the highest energy intake, dry matter (DM) digestibility, and milk yield. The fresh forage diets (SFF and SFB) increased DM and crude protein (CP) intake, CP digestibility, and milk CN compared with the MHB diet. The diets supplemented with energy (SFB, MHB) reduced milk fat and urea, improved CP utilization for casein synthesis, and limited body fat mobilization, in accordance with a lower level of nonesterified fatty acids and higher levels of glucose and IGF-1. With regard to CSN1S1 genotype, AA goats showed higher CP digestibility and lower free thyroxine hormone and cholesterol levels than AF

  19. 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...

  20. Produção e qualidade de forragem da mistura de aveia e azevém sob dois métodos de estabelecimento Forage production and quality of oats and ryegrass mixture under two establishment methods

    Directory of Open Access Journals (Sweden)

    Marta Gomes da Rocha

    2007-02-01

    Full Text Available Neste trabalho, comparou-se a sobre-semeadura de aveia (Avena strigosa Schreb. e azevém (Lolium multiflorum Lam. em pastagem de coastcross (Cynodon dactylon (L. Pers. ao cultivo estreme como métodos de implantação de pastagens de inverno em sistema de pastejo rotacionado com vacas holandesas em lactação. Foram avaliados a produção total de MS (PTF, a massa de forragem de entrada (MFE, o resíduo (RES, as perdas de forragem (PD, a taxa de acúmulo diário de MS (TAD, a carga animal (CA, a oferta de forragem (OF e a biomassa de lâminas foliares (BLF. Para determinação da composição botânica, foram separados em cada espécie (aveia, azevém e coastcross os componentes estruturais folha, colmo e material senescente. Na entrada e saída dos animais da pastagem, foram colhidas amostras por simulação de pastejo para determinação dos teores de PB e FDN. Não houve diferença entre tratamentos para PTF, MFE, RES, PD, TAD, OF e CA. A oferta média de lâminas foliares foi de 1,3±0,67 kg LF/100 kg PV. A sobre-semeadura proporcionou maior biomassa de lâminas foliares disponibilizando forragem com maior teor de PB e menor de FDN na entrada e saída dos animais da pastagem.The oats (Avena strigosa Schreb. and ryegrass (Lolium multiflorum Lam. sodseeding in pasture of coastcross (Cynodon dactylon (L. Pers. was compared to oats and ryegrass in extreme tillage, as establishment methods of winter pastures under rotational stocking with lactating Holstein dairy cows. The total DM production (DMP, pre-grazed herbage mass, residue (RES, forage losses (FL, daily DM accumulation rate (DAR, stocking rate (SR, forage on offer (FO and leaf blade biomass (LBB were evaluated. For botanical composition, oats, ryegrass and coastcross were separated in the structural components: leaves, stems and dead material. Hand plucking samples for CP and NDF determinations were collected during pre- and post-grazing. The DMP, HM, RES, FL, DAR, SR and FO were not

  1. Traffic noise reduces foraging efficiency in wild owls

    Science.gov (United States)

    Senzaki, Masayuki; Yamaura, Yuichi; Francis, Clinton D.; Nakamura, Futoshi

    2016-08-01

    Anthropogenic noise has been increasing globally. Laboratory experiments suggest that noise disrupts foraging behavior across a range of species, but to reveal the full impacts of noise, we must examine the impacts of noise on foraging behavior among species in the wild. Owls are widespread nocturnal top predators and use prey rustling sounds for localizing prey when hunting. We conducted field experiments to examine the effect of traffic noise on owls’ ability to detect prey. Results suggest that foraging efficiency declines with increasing traffic noise levels due to acoustic masking and/or distraction and aversion to traffic noise. Moreover, we estimate that effects of traffic noise on owls’ ability to detect prey reach >120 m from a road, which is larger than the distance estimated from captive studies with bats. Our study provides the first evidence that noise reduces foraging efficiency in wild animals, and highlights the possible pervasive impacts of noise.

  2. Dimorphic foraging behaviors and the evolution of hominid hunting.

    Science.gov (United States)

    Fessler, Daniel M T

    2002-01-01

    In contemporary foraging societies men typically hunt more than women. This observation has played an important role in many reconstructions of hominid evolution. The gender difference in human hunting, likely a product of both ecological and cultural factors, is mirrored by a similar sex difference among nonhuman primates. Existing explanations of such primate behavioral dimorphism are augmented by the recognition of an additional factor that may contribute to differences between males and females in the value of meat. Episodic female immunosuppression is a normal part of reproduction. Because meat is a source of pathogens, females can be expected to exhibit less constant attraction to meat. Sexual dimorphism in the attraction to meat may then contribute to dimorphic foraging specializations, a divergence that is likely augmented by the differential value of insectivory across the sexes. With the rise of cultural transmission of foraging knowledge, dimorphic foraging behaviors would have been reinforced, creating a more comprehensive gender-based division of labor.

  3. PLANT RAW MATERIAL EXTRACTS AS COMPONENTS OF COSMETIC PRODUCTS AND FORMULATIONS FOR TOPICAL ADMINISTRATION: THE PRODUCT RANGE, THE PRODUCTION CHARACTERISTICS (REVIEW

    Directory of Open Access Journals (Sweden)

    S. B. Evseeva

    2016-01-01

    Full Text Available In contemporary pharmaceutical practice extracts are used as a separate cosmetic product and as an intermediate for external medicinal forms (ointments, gels, liniments and cosmetic forms. Their range is highly diverse.The aim is an overview of the scientific and technical information concerning plant  raw materials extracts using in the external drug and cosmetic products.Methods. To describe the range of extracts proposed for external use the analysis of the proposals of Russian and foreign producers submitted their official websites and online trading platforms was used. The specificity of extraction of biologically active substances of plant extracting agents: water, ethyl alcohol, glycols, vegetable oils, carbon dioxide used to obtain extracts was described on the basis of available scientific literature (eLIBRARY, PubMed, Cyberleninca, Google Books. Results. Examples of external drugs and cosmetic products based on plant raw materials extracts from a range of pharmaceutical organizations are given. It was found that from the extracting solvent used the range is presented by hydrophilic, such as glycol (propylene glycol, glycerin, water, alcoholic extracts; lipophilic (oil, CO2-extracts, and two-phase (caprylic/caprate triglyceride/water extracts. The main features of the extracting solvent used for this category of extracts: the specifics of the use in cosmetics (the skin specific effect, in particular selectivity to groups of biologically active plant substances, microbiological purity, are noted. Results of research data on the study of the prospects for the use of cosmetic ingredients – silicones, caprylic/ capric triglyceride, isopropyl myristate both solvents. The extraction techniques: classical (maceration, percolation and intensified (electro-plasma dynamic extraction, vacuum extraction circulation, CO2 supercritical extraction used in industry to produce cosmetic extracts are described

  4. Forage maize nutritional quality according to organic and inorganic fertilization

    Directory of Open Access Journals (Sweden)

    Alejandro Moreno-Reséndez

    2017-01-01

    Full Text Available The research was conducted on a commercial land plot from the ejido Granada, municipality of M atamoros, Coahuila, situated inside the Comarca Lagunera, from April to August 2015, in order to establish the effect of two fertilization sources – organic and inorganic, upon the nutritional quality of forage maize during the spring - summer cycle with a r andomized block experimental design. T 1 = Acadian soil +Acadian foliage (marine algae extracts and T 2 = Regional control, with 16 replications. The evaluated variables were the nutritional quality of forage maize and the milk production (L•t - 1 dry matter an d L•ha - 1 . Due to the effect of the evaluated treatments, statistical differences were registered, both for, nutritional values of forage maize, such as: neutral and acid detergent fiber, non - fiber carbohydrates, total digestible nutrients, total net energ y for lactation and for milk production, in favor of organic fertilization. Therefore, it can be concluded that fertilizers of marine origin applied to forage maize increased both nutritional quality of forage maize and milk yield per ton of dry matter and per hectare of this forage.

  5. Produção de híbridos de amendoim forrageiro por meio de hibridação artificial Production of forage peanut hybrids through artificial hybridization

    Directory of Open Access Journals (Sweden)

    Marilda Augusta Peres Oliveira

    2002-06-01

    Full Text Available O objetivo deste trabalho foi a obtenção de híbridos de amendoim forrageiro por meio da hibridação artificial. O experimento foi realizado na Embrapa-Centro Nacional de Pesquisa de Recursos Genéticos e Biotecnologia, durante a época de florescimento dos acessos de Arachis pintoi Krap. & W. C. Gregory e de A. repens Handro. Cerca de 700 polinizações produziram 27 segmentos de frutos, com taxas de fecundação que variaram entre 1,1 e 12,9%, considerando-se todas as combinações híbridas. Os híbridos intra-específicos de A. pintoi produziram sementes F2, e os interespecíficos não produziram semente. A técnica de hibridação utilizada nas espécies forrageiras necessitou de ajustes, devido a diferenças observadas em relação ao amendoim cultivado, entre elas o hábito de crescimento.The purpose of this work was to obtain forage peanut hybrids through artificial hybridization. The experiment was conducted in a screenhouse at Embrapa-Centro Nacional de Pesquisa de Recursos Genéticos e Biotecnologia during the flowering period of Arachis pintoi Krap. & W. C. Gregory and A. repens Handro accessions. About 700 pollinations produced 27 fruit segments and the fertilization rates ranged from 1.1 to 12.9% for all cross combinations. The intraspecific hybrids produced F2 seeds, which did not occur to the interspecific hybrids. To effect the hybridization technique, adjustments were necessary to forage Arachis species, in relation to cultivated peanut, since differences in the growth habit were verified.

  6. Variation in home range size of red foxes Vulpes vulpes along a gradient of productivity and human landscape alteration

    Science.gov (United States)

    2017-01-01

    Home range size is a fundamental concept for understanding animal dispersion and ecological needs, and it is one of the most commonly reported ecological attributes of free-ranging mammals. Previous studies indicate that red foxes Vulpes vulpes display great variability in home range size. Yet, there has been little consensus regarding the reasons why home range sizes of red foxes vary so extensively. In this study, we examine possible causes of variation in red fox home range sizes using data from 52 GPS collared red foxes from four study areas representing a gradient of landscape productivity and human landscape alteration in Norway and Sweden. Using 90% Local Convex Hull home range estimates, we examined how red fox home range size varied in relation to latitude, elevation, vegetation zone, proportion of agricultural land and human settlement within a home range, and sex and age. We found considerable variation in red fox home range sizes, ranging between 0.95 km2 to 44 km2 (LoCoH 90%) and 2.4 km2 to 358 km2 (MCP 100%). Elevation, proportion of agricultural land and sex accounted for 50% of the variation in home range size found amongst foxes, with elevation having the strongest effect. Red foxes residing in more productive landscapes (those in more southern vegetation zones), had home ranges approximately four times smaller than the home ranges of foxes in the northern boreal vegetation zone. Our results indicate that home range size was influenced by a productivity gradient at both the landscape (latitude) and the local (elevation) scale. The influence of the proportion of agriculture land on home range size of foxes illustrates how human landscape alteration can affect the space use and distribution of red foxes. Further, the variation in home range size found in this study demonstrates the plasticity of red foxes to respond to changing human landscape alteration as well as changes in landscape productivity, which may be contributing to red fox population

  7. Higher measured than modeled ozone production at increased NOx levels in the Colorado Front Range

    Science.gov (United States)

    Baier, Bianca C.; Brune, William H.; Miller, David O.; Blake, Donald; Long, Russell; Wisthaler, Armin; Cantrell, Christopher; Fried, Alan; Heikes, Brian; Brown, Steven; McDuffie, Erin; Flocke, Frank; Apel, Eric; Kaser, Lisa; Weinheimer, Andrew

    2017-09-01

    Chemical models must correctly calculate the ozone formation rate, P(O3), to accurately predict ozone levels and to test mitigation strategies. However, air quality models can have large uncertainties in P(O3) calculations, which can create uncertainties in ozone forecasts, especially during the summertime when P(O3) is high. One way to test mechanisms is to compare modeled P(O3) to direct measurements. During summer 2014, the Measurement of Ozone Production Sensor (MOPS) directly measured net P(O3) in Golden, CO, approximately 25 km west of Denver along the Colorado Front Range. Net P(O3) was compared to rates calculated by a photochemical box model that was constrained by measurements of other chemical species and that used a lumped chemical mechanism and a more explicit one. Median observed P(O3) was up to a factor of 2 higher than that modeled during early morning hours when nitric oxide (NO) levels were high and was similar to modeled P(O3) for the rest of the day. While all interferences and offsets in this new method are not fully understood, simulations of these possible uncertainties cannot explain the observed P(O3) behavior. Modeled and measured P(O3) and peroxy radical (HO2 and RO2) discrepancies observed here are similar to those presented in prior studies. While a missing atmospheric organic peroxy radical source from volatile organic compounds co-emitted with NO could be one plausible solution to the P(O3) discrepancy, such a source has not been identified and does not fully explain the peroxy radical model-data mismatch. If the MOPS accurately depicts atmospheric P(O3), then these results would imply that P(O3) in Golden, CO, would be NOx-sensitive for more of the day than what is calculated by models, extending the NOx-sensitive P(O3) regime from the afternoon further into the morning. These results could affect ozone reduction strategies for the region surrounding Golden and possibly other areas that do not comply with national ozone regulations

  8. Higher measured than modeled ozone production at increased NOx levels in the Colorado Front Range

    Directory of Open Access Journals (Sweden)

    B. C. Baier

    2017-09-01

    Full Text Available Chemical models must correctly calculate the ozone formation rate, P(O3, to accurately predict ozone levels and to test mitigation strategies. However, air quality models can have large uncertainties in P(O3 calculations, which can create uncertainties in ozone forecasts, especially during the summertime when P(O3 is high. One way to test mechanisms is to compare modeled P(O3 to direct measurements. During summer 2014, the Measurement of Ozone Production Sensor (MOPS directly measured net P(O3 in Golden, CO, approximately 25 km west of Denver along the Colorado Front Range. Net P(O3 was compared to rates calculated by a photochemical box model that was constrained by measurements of other chemical species and that used a lumped chemical mechanism and a more explicit one. Median observed P(O3 was up to a factor of 2 higher than that modeled during early morning hours when nitric oxide (NO levels were high and was similar to modeled P(O3 for the rest of the day. While all interferences and offsets in this new method are not fully understood, simulations of these possible uncertainties cannot explain the observed P(O3 behavior. Modeled and measured P(O3 and peroxy radical (HO2 and RO2 discrepancies observed here are similar to those presented in prior studies. While a missing atmospheric organic peroxy radical source from volatile organic compounds co-emitted with NO could be one plausible solution to the P(O3 discrepancy, such a source has not been identified and does not fully explain the peroxy radical model–data mismatch. If the MOPS accurately depicts atmospheric P(O3, then these results would imply that P(O3 in Golden, CO, would be NOx-sensitive for more of the day than what is calculated by models, extending the NOx-sensitive P(O3 regime from the afternoon further into the morning. These results could affect ozone reduction strategies for the region surrounding Golden and possibly other areas that do not comply with national ozone

  9. 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

  10. Ranging Behaviour of Commercial Free-Range Laying Hens

    Science.gov (United States)

    Chielo, Leonard Ikenna; Pike, Tom; Cooper, Jonathan

    2016-01-01

    Simple Summary Commercial free-range production has become a significant sector of the fresh egg market due to legislation banning conventional cages and consumer preference for products perceived as welfare friendly, as access to outdoor range can lead to welfare benefits such as greater freedom of movement and enhanced behavioural opportunities. This study investigated dispersal patterns, feather condition and activity of laying hens in three distinct zones of the range area; the apron area near shed; enriched zone 10–50 m from shed; and outer range beyond 50 m, in six flocks of laying hens under commercial free-range conditions varying in size between 4000 and 24,000 hens. Each flock was visited for four days to record number of hens in each zone, their behaviour, feather condition and nearest neighbour distances (NND), as well as record temperature and relative humidity during the visit. Temperature and relative humidity varied across the study period in line with seasonal variations and influenced the use of range with fewer hens out of shed as temperature fell or relative humidity rose. On average, 12.5% of the hens were observed on the range and most of these hens were recorded in the apron zone as hen density decreased rapidly with increasing distance from the shed. Larger flocks appeared to have a lower proportion of hens on range. The hens used the range more in the early morning followed by a progressive decrease through to early afternoon. The NND was greatest in the outer range and decreased towards the shed. Feather condition was generally good and hens observed in the outer range had the best overall feather condition. Standing, pecking, walking and foraging were the most commonly recorded behaviours and of these, standing occurred most in the apron whereas walking and foraging behaviours were recorded most in the outer range. This study supported the findings of previous studies that reported few hens in the range and greater use of areas closer

  11. Produção de forragem do capim-Tanzânia (Panicum maximum Jacq. cv. Tanzânia-1 pastejado em diferentes alturas Forage production of Tanzaniagrass (Panicum maximum Jacq. cv. Tanzania-1 grazed at different heights

    Directory of Open Access Journals (Sweden)

    Clovenilson Cláudio Perissato Cano

    2004-12-01

    randomized design was used with two replications and five evaluation periods were performed. The GLLM, GSSM, MDM, GMF, FM, LAI, DMAR, and TFM increased by increasing of the pasture height, the percentage of NCS, SCWL and dead material decreased with the pasture height. Tanzaniagrass management, based on the pasture height from 40 to 60 cmshowed good morphologic composition and high leaves availability for grazing, good ground cover and dry matter accumulation rate, while the heights of 20 and 80 cm shall not be recommended for the Tanzania grass management when the objective is high production of forage quality.

  12. The economic impact of longer range weather information on the production of peas in Wisconsin

    Science.gov (United States)

    Smith, K. R.; Torkelson, A. W.

    1972-01-01

    The extent of benefits which will be realized in the pea industry as a result of improved long range weather forecasts are outlined. Particular attention was given to planting and harvesting operations.

  13. Preliminary Products of Precise Orbit Determination Using Satellite Laser Ranging Observations for ILRS AAC

    OpenAIRE

    Young-Rok Kim; Sang-Young Park; Eun-Seo Park; Hyung-Chul Lim

    2012-01-01

    In this study, we present preliminary results of precise orbit determination (POD) using satellite laser ranging (SLR) observations for International Laser Ranging Service (ILRS) Associate Analysis Center (AAC). Using SLR normal point observations of LAGEOS-1, LAGEOS-2, ETALON-1, and ETALON-2, the NASA/GSFC GEODYN II software are utilized for POD. Weekly-based orbit determination strategy is applied to process SLR observations and the post-fit residuals check, and external orbit comparison ar...

  14. Understanding investors' decisions to purchase innovative products : Drivers of adoption timing and range

    NARCIS (Netherlands)

    Hoffmann, A.O.I.; Broekhuizen, T.L.J.

    2010-01-01

    This paper integrates findings from marketing and finance literature to increase our understanding of consumers' decisions to purchase innovative investment products. Two different surveys administered to individual investors examine the psychological and sociological drivers of dispositional

  15. Root foraging influences plant growth responses to earthworm foraging.

    Directory of Open Access Journals (Sweden)

    Erin K Cameron

    Full Text Available Interactions among the foraging behaviours of co-occurring animal species can impact population and community dynamics; the consequences of interactions between plant and animal foraging behaviours have received less attention. In North American forests, invasions by European earthworms have led to substantial changes in plant community composition. Changes in leaf litter have been identified as a critical indirect mechanism driving earthworm impacts on plants. However, there has been limited examination of the direct effects of earthworm burrowing on plant growth. Here we show a novel second pathway exists, whereby earthworms (Lumbricus terrestris L. impact plant root foraging. In a mini-rhizotron experiment, roots occurred more frequently in burrows and soil cracks than in the soil matrix. The roots of Achillea millefolium L. preferentially occupied earthworm burrows, where nutrient availability was presumably higher than in cracks due to earthworm excreta. In contrast, the roots of Campanula rotundifolia L. were less likely to occur in burrows. This shift in root behaviour was associated with a 30% decline in the overall biomass of C. rotundifolia when earthworms were present. Our results indicate earthworm impacts on plant foraging can occur indirectly via physical and chemical changes to the soil and directly via root consumption or abrasion and thus may be one factor influencing plant growth and community change following earthworm invasion. More generally, this work demonstrates the potential for interactions to occur between the foraging behaviours of plants and soil animals and emphasizes the importance of integrating behavioural understanding in foraging studies involving plants.

  16. Root foraging influences plant growth responses to earthworm foraging.

    Science.gov (United States)

    Cameron, Erin K; Cahill, James F; Bayne, Erin M

    2014-01-01

    Interactions among the foraging behaviours of co-occurring animal species can impact population and community dynamics; the consequences of interactions between plant and animal foraging behaviours have received less attention. In North American forests, invasions by European earthworms have led to substantial changes in plant community composition. Changes in leaf litter have been identified as a critical indirect mechanism driving earthworm impacts on plants. However, there has been limited examination of the direct effects of earthworm burrowing on plant growth. Here we show a novel second pathway exists, whereby earthworms (Lumbricus terrestris L.) impact plant root foraging. In a mini-rhizotron experiment, roots occurred more frequently in burrows and soil cracks than in the soil matrix. The roots of Achillea millefolium L. preferentially occupied earthworm burrows, where nutrient availability was presumably higher than in cracks due to earthworm excreta. In contrast, the roots of Campanula rotundifolia L. were less likely to occur in burrows. This shift in root behaviour was associated with a 30% decline in the overall biomass of C. rotundifolia when earthworms were present. Our results indicate earthworm impacts on plant foraging can occur indirectly via physical and chemical changes to the soil and directly via root consumption or abrasion and thus may be one factor influencing plant growth and community change following earthworm invasion. More generally, this work demonstrates the potential for interactions to occur between the foraging behaviours of plants and soil animals and emphasizes the importance of integrating behavioural understanding in foraging studies involving plants.

  17. The forager oral tradition and the evolution of prolonged juvenility.

    Science.gov (United States)

    Scalise Sugiyama, Michelle

    2011-01-01

    The foraging niche is characterized by the exploitation of nutrient-rich resources using complex extraction techniques that take a long time to acquire. This costly period of development is supported by intensive parental investment. Although human life history theory tends to characterize this investment in terms of food and care, ethnographic research on foraging skill transmission suggests that the flow of resources from old-to-young also includes knowledge. Given the adaptive value of information, parents may have been under selection pressure to invest knowledge - e.g., warnings, advice - in children: proactive provisioning of reliable information would have increased offspring survival rates and, hence, parental fitness. One way that foragers acquire subsistence knowledge is through symbolic communication, including narrative. Tellingly, oral traditions are characterized by an old-to-young transmission pattern, which suggests that, in forager groups, storytelling might be an important means by which adults transfer knowledge to juveniles. In particular, by providing juveniles with vicarious experience, storytelling may expand episodic memory, which is believed to be integral to the generation of possible future scenarios (i.e., planning). In support of this hypothesis, this essay reviews evidence that: mastery of foraging knowledge and skill sets takes a long time to acquire; foraging knowledge is transmitted from parent to child; the human mind contains adaptations specific to social learning; full assembly of learning mechanisms is not complete in early childhood; and forager oral traditions contain a wide range of information integral to occupation of the foraging niche. It concludes with suggestions for tests of the proposed hypothesis.

  18. The forager oral tradition and the evolution of prolonged juvenility

    Directory of Open Access Journals (Sweden)

    Michelle Scalise Sugiyama

    2011-08-01

    Full Text Available The foraging niche is characterized by the exploitation of nutrient-rich resources using complex extraction techniques that take a long time to acquire. This costly period of development is supported by intensive parental investment. Although human life history theory tends to characterize this investment in terms of food and care, ethnographic research on foraging skill transmission suggests that the flow of resources from old to young also includes knowledge. Given the adaptive value of information, parents may have been under selection pressure to invest knowledge—e.g., warnings, advice--in children: proactive provisioning of reliable information would have increased offspring survival rates and, hence, parental fitness. One way that foragers acquire subsistence knowledge is through symbolic communication, including narrative. Tellingly, oral traditions are characterized by an old-to-young transmission pattern, which suggests that, in forager groups, storytelling might be an important means by which adults transfer knowledge to juveniles. In particular, by providing juveniles with vicarious experience, storytelling may expand episodic memory, which is believed to be integral to the generation of possible future scenarios (i.e., planning. In support of this hypothesis, this essay reviews evidence that: mastery of foraging knowledge and skill sets takes a long time to acquire; foraging knowledge is transmitted from parent to child; the human mind contains adaptations specific to social learning; full assembly of learning mechanisms is not complete in early childhood; and forager oral traditions contain a wide range of information integral to occupation of the foraging niche. It concludes with suggestions for tests of the proposed hypothesis.

  19. [Application and prospect of near infrared reflectance spectroscopy in forage analysis].

    Science.gov (United States)

    Ren, Xiu-Zhen; Guo, Hong-Ru; Jia, Yu-Shan; Ge, Gen-Tu; Wang, Kun

    2009-03-01

    Forage was the material basis of animal husbandry production, and its quality is directly related to the quality of animal products. It was very important to control the forage quality and detect the composition of forage raw materials in forage production. Predication of forage quality was often completed by the traditional and classical methods in the past, which were complex, time consuming and expensive, and could not acquire the nutritional value of forage timely. Near infrared reflectance spectroscopy was a highly efficient and rapid modern analysis technique developed in 1970's. It comprehensively applied the latest research results of computer technique, spectroscopy and chemometrics, and has been widely used in various fields owing to its unique advantages such as being timely, less expensive, non-destructive, and so on. Near infrared reflectance spectroscopy has gained more and more importance though its application to forage analysis was very late. Presently, not only conventional composition (such as moisture, dry matter, crude protein, crude fiber, crude fat, crude ash neutral detergent fiber, acid detergent fiber, etc.), but also non-conventional composition (including minerals, trace elements, enzyme and anti-nutritional factors etc. ) and anti-nutritional factors in forage were determined by means of near infrared reflectance spectroscopy. Testing and analyzing the conventional composition in forage was the traditional applied field of near infrared reflectance spectroscopy, a lot of studies of which were done and it has already been one of the standard methods of testing the conventional composition. Forage bioavaibility was also evaluated by near infrared reflectance spectroscopy, so as to assess the utilization rate and nutritional value of forage. Moreover, near infrared spectroscopy could be used successfully to predict the botanical composition in grassland and leaf/stem ratios. Near infrared spectroscopy technique and its application and

  20. Forage yield and quality response of annual ryegrass ( Lolium ...

    African Journals Online (AJOL)

    Water and nitrogen shortages in annual ryegrass (Lolium multiflorum) production can be improved by using proper irrigation and nitrogen scheduling methods. The aim of this research was to analyse the effect of water and nitrogen application on dry matter production and forage quality of annual ryegrass. Treatments ...

  1. Southern African pasture and forage science entering the 21st ...

    African Journals Online (AJOL)

    Given the global challenges of mitigating and alleviating land degradation and ensuring food security, particularly through protein production, pasture and forage science together with rangeland science will remain imperative to sustainable livestock production systems. Recognising the scientific principles developed in this ...

  2. Bumble bee nest abundance, foraging distance, and host-plant reproduction: implications for management and conservation.

    Science.gov (United States)

    Geib, Jennifer C; Strange, James P; Galenj, Candace

    2015-04-01

    Recent reports of global declines in pollinator species imply an urgent need to assess the abundance of native pollinators and density-dependent benefits for linked plants. In this study, we investigated (1) pollinator nest distributions and estimated colony abundances, (2) the relationship between abundances of foraging workers and the number of nests they represent, (3) pollinator foraging ranges, and (4) the relationship between pollinator abundance and plant reproduction. We examined these questions in an alpine ecosystem in the Colorado Rocky Mountains, focusing on four alpine bumble bee species (Bombus balteatus, B. flavifrons, B. bifarius, and B. sylvicola), and two host plants that differ in their degrees of pollinator specialization (Trifolium dasyphyllum and T. parryi). Using microsatellites, we found that estimated colony abundances among Bombus species ranged from ~18 to 78 colonies/0.01 km2. The long-tongued species B. balteatus was most common, especially high above treeline, but the subalpine species B. bifarius was unexpectedly abundant for this elevation range. Nests detected among sampled foragers of each species were correlated with the number of foragers caught. Foraging ranges were smaller than expected for all Bombus species, ranging from 25 to 110 m. Fruit set for the specialized plant, Trifolium parryi, was positively related to the abundance of its Bombus pollinator. In contrast, fruit set for the generalized plant, T. dasyphyllum, was related to abundance of all Bombus species. Because forager abundance was related to nest abundance of each Bombus species and was an equally effective predictor of plant fecundity, forager inventories are probably suitable for assessing the health of outcrossing plant populations. However, nest abundance, rather than forager abundance, better reflects demographic and genetic health in populations of eusocial pollinators such as bumble bees. Development of models incorporating the parameters we have measured

  3. Relação entre características morfológicas e produtivas de clones de palma-forrageira Relationship between morphological characteristics and productivity of cactus forage clones

    Directory of Open Access Journals (Sweden)

    Nalígia Gomes de Miranda e Silva

    2010-11-01

    Full Text Available Objetivou-se avaliar a relação entre as características morfológicas e produtivas de clones de palma-forrageira para identificação daqueles que contribuem diretamente na produção. Foram avaliados 50 clones de palma-forrageira estabelecidos no palmal há cinco anos e submetidos ao primeiro corte dois anos antes da avaliação. Foram avaliadas as características da planta e do cladódio, e os dados foram analisados pela estatística descritiva, correlação de Pearson e pela análise de trilha das variáveis-independentes explicativas sobre a produção de matéria seca em t/ha/2anos (variável-dependente principal. A produção variou entre clones e foi maior nos clones 8, 782 e 418, cujas produções de matéria seca de 40,8; 18,1 e 12,1 t MS/ha/2anos, respectivamente. Houve baixa correlação entre quase todas as variáveis explicativas e a produção considerada variável principal, por isso, foi necessária a associação de características. As características altura associada à largura da planta explicaram melhor o potencial de produção de matéria seca em t/ha/2anos por apresentarem alta correlação com a produção (r = 0,71 e maior efeito direto (0,69. A seleção indireta e não-destrutiva para a produção deve ser baseada em plantas com maior altura e largura.This research evaluated the relationship among the morphological and productive characteristics of clones of cactus forage for identification of those that directly contribute to the production. It was evaluated 50 clones of cactus forage planted five years ago and submitted to the first cut two years before the evaluation. Characteristics of the plant and of the cladode were evaluated and data were analyzed by descriptive characteristics, Pearson correlation and by path analysis of the explanatory independent variables on the dry matter production in t/ha/2 years (main dependent variable. Production varied among clones and it was the highest in clones 8, 782 e 418

  4. Food foraging of honey bees in a microwave field (2. 45 GHz CW)

    Energy Technology Data Exchange (ETDEWEB)

    Gary, N.E.; Westerdahl, B.B.

    1982-02-15

    Honey bees were trained to fly 400 m from their colony to an indoor laboratory foraging arena exposed to 2.45 GHz continuous wave microwaves at 5 power densities (0, 5, 10, 20, and 40 mW/cm/sup 2/). Foraging behavior did not differ from controls foraging within an unexposed sham arena in (1) number of round trips completed during a 3-h exposure session, (2) round trip time between the colony and the foraging arena, and (3) the length of time required to navigate the illuminated foraging arena. This study indicates that honey bees would not be adversely affected by foraging within a similar microwave field that would exist in future receiving antennae for the proposed solar power satellite energy transmission system in which power levels are expected to range from 23 mW/cm/sup 2/ at the antenna center to 1 mW/cm/sup 2/ at the edge.

  5. Treatment of tropical forages with exogenous fibrolytic enzymes: effects on chemical composition and in vitro rumen fermentation.

    Science.gov (United States)

    Díaz, A; Ranilla, M J; Giraldo, L A; Tejido, M L; Carro, M D

    2015-04-01

    The effects of three treatments of fibrolytic enzymes (cellulase from Trichoderma longibrachiatum (CEL), xylanase from rumen micro-organisms (XYL) and a 1:1 mixture of CEL and XYL (MIX) on the in vitro fermentation of two samples of Pennisetum clandestinum (P1 and P2), two samples of Dichanthium aristatum (D1 and D2) and one sample of each Acacia decurrens and Acacia mangium (A1 and A2) were investigated. The first experiment compared the effects of two methods of applying the enzymes to forages, either at the time of incubation or 24 h before, on the in vitro gas production. In general, the 24 h pre-treatment resulted in higher values of gas production rate, and this application method was chosen for a second study investigating the effects of enzymes on chemical composition and in vitro fermentation of forages. The pre-treatment with CEL for 24 h reduced (p < 0.05) the content of neutral detergent fibre (NDF) of P1, P2, D1 and D2, and that of MIX reduced the NDF content of P1 and D1, but XYL had no effect on any forage. The CEL treatment increased (p < 0.05) total volatile fatty acid (VFA) production for all forages (ranging from 8.6% to 22.7%), but in general, no effects of MIX and XYL were observed. For both P. clandestinum samples, CEL treatment reduced (p < 0.05) the molar proportion of acetate and increased (p < 0.05) that of butyrate, but only subtle changes in VFA profile were observed for the rest of forages. Under the conditions of the present experiment, the treatment of tropical forages with CEL stimulated their in vitro ruminal fermentation, but XYL did not produce any positive effect. These results showed clearly that effectiveness of enzymes varied with the incubated forage and further study is warranted to investigate specific, optimal enzyme-substrate combinations. Journal of Animal Physiology and Animal Nutrition © 2014 Blackwell Verlag GmbH.

  6. Potency Of Clitoria Ternatea As Forage For Livestock

    Directory of Open Access Journals (Sweden)

    Endang Sutedi

    2013-06-01

    Full Text Available Availability of forage is one of the factors determining the success of ruminant livestock production, especially during drought that resulting in poor livestock condition. Forage legume is an important group of forage plants, containing high nutritive value. One of the legume plants which potential as ruminant feed is Clitoria ternatea. This plant can grow well in all types of soil and dry conditions, also produces seed continously. The production of forage was 25-29 ton DM/ha with seed production was 2.2 ton DM/ha per harvest (42 day cutting interval. The crude protein and crude fiber contents of C. ternatea leaf were 21.5 and 29%, respectively. Meanwhile, the crude protein, crude fat and sugar contents of C. ternatea seed were 25-38,10 and 5%, respectively. This plant can be fed to ruminant as fresh forage or hay with no negative effect on growth performance of animal. The average daily gain of cattle grazing on mixture of Brachiaria mutica grass and C. ternatea was 680 g/day. The value of DM and OM digestibilities of C. ternatea in cattle were 50.15 and 53.47%, respectively. Feeding C. ternatea to dairy cow impoved the content of fat and total solid of milk, meanwhile feeding it to male sheep improved quality of semen.

  7. Evidence for foraging -site fidelity and individual foraging behavior of pelagic cormorants rearing chicks in the gulf of Alaska

    Science.gov (United States)

    Kotzerka, J.; Hatch, Shyla A.; Garthe, S.

    2011-01-01

    The Pelagic Cormorant (Phalacrocorax pelagicus) is the most widespread cormorant in the North Pacific, but little is known about its foraging and diving behavior. However, knowledge of seabirds' foraging behavior is important to understanding their function in the marine environment. In 2006, using GPS dataloggers, we studied the foraging behavior of 14 male Pelagic Cormorants rearing chicks on Middleton Island, Alaska. For foraging, the birds had high fidelity to a small area 8 km north of the colony. Within that area, the cormorants' diving activity was of two distinct kinds-near-surface dives (1-6 m) and benthic dives (28-33 m). Individuals were consistent in the depths of their dives, either mostly shallow or mostly deep. Few showed no depth preference. Dive duration, time at maximum depth, and pauses at the water surface between consecutive dives were shorter for shallow dives than for deep dives. The cormorants made dives of both types throughout the day, but the frequency of deep dives increased toward evening. Maximum foraging range was 9 km; maximum total distance traveled per trip was 43.4 km. Trip durations ranged from 0.3 to 7.7 hr. Maximum depth of a dive was 42.2 m, and duration of dives ranged from 4 to 120 sec. We found that Pelagic Cormorants at Middleton Island were faithful to one particular foraging area and individuals dived in distinct patterns. Distinct, specialized foraging behavior may be advantageous in reducing intra- and interspecific competition but may also render the species vulnerable to changing environmental conditions. Copyright ?? The Cooper Ornithological Society 2011.

  8. Capacidade de produção e consumo específico de energia em picadoras forrageiras tipo desintegrador/picador/moedor Production capacity and specific energy consumption in forage choppers of the disintegrator/ chopper/grinder type

    Directory of Open Access Journals (Sweden)

    Luiz H. de Souza

    2009-02-01

    Full Text Available Avaliaram-se a capacidade de produção e o consumo específico de energia em picadoras de forragem tipo Desintegrador/Picador/Moedor no processamento de capim-elefante considerando-se, como tratamentos, três picadoras (DPM-1, DPm-2 e DPM-4, cinco diferentes rotações, três ângulos oblíquos das facas e dois ângulos do gume das facas. O delineamento experimental foi o inteiramente casualizado com duas repetições e os resultados avaliados por meio da análise de regressão. O ângulo oblíquo de 10º propiciou, aos três DPMs, maior eficiência e, em algumas situações o ângulo oblíquo de 38º proporcionou melhor desempenho aos DPMs 1 e 2; enquanto em outras, o ângulo de 30º proporcionou ao DPM-4, melhor desempenho. É possível baixar o custo de produção quando se trabalha em menores rotações, em virtude do valor do consumo específico ser reduzido. Embora o DPM-4 tenha apresentado menor demanda energética, ressalta-se que esta máquina possui maior preço de aquisição que os outros dois modelos e maior dificuldade de alimentação, obrigando o produtor a contratar mais uma pessoa para executar este processo.The production capacity and specific energy consumption in forage choppers type Disintegrator/Chopper/Grinder for elephant grass processing were evaluated. The treatments consisted of the combination of three forage choppers (DPM-1, DPm-2 and DPM-4, each operating in five different rotations, three oblique angles of the knives and two angles of the knives' edges. The experimental design used was completely randomized with two repetitions, and the results were evaluated by means of the regression analysis. The oblique angle of 10º led to greater efficiency for the three DPMs. In some situations, the oblique angle of 38º provided better performance for DPMs 1 and 2, while in others, the angle of 30º provided better performance for DPM-4. It is possible to lower production costs, when working at lower rotation speeds, due

  9. Optimizing the biocatalytic productivity of an engineered sialidase from Trypanosoma rangeli for 3′-sialyllactose production

    DEFF Research Database (Denmark)

    Zeuner, Birgitte; Luo, Jianquan; Nyffenegger, Christian

    2014-01-01

    -linked Tr6, and (iv) Tr6 catalysis in a membrane reactor. Tr6 immobilized on MNPs gave a biocatalytic productivity of 84mg 3′-sialyllactose/mg Tr6 after seven consecutive reaction runs. Calcium-alginate and membrane immobilization were inefficient. Using free Tr6 in a 10kDa membrane reactor produced a 9......-fold biocatalytic productivity increase compared to using free Tr6 in a batch reactor giving 306mg 3′-sialyllactose/mg Tr6 after seven consecutive reaction runs. The 3′-sialyllactose yield on α-2,3-bound sialic acid in CGMP was 74%. Using circular dichroism, a temperature denaturation midpoint of Tr6...

  10. Power laws in cone production of longleaf pine across its native range in the United States

    Science.gov (United States)

    Xiongwen Chen; Qinfeng Guo; Dale G. Brockway

    2017-01-01

    Longleaf pine (Pinus palustris Mill.) forests in the southeastern United States are considered endangered ecosystems, because of their dramatic decrease in area since European colonization and poor rates of recovery related to episodic natural regeneration. Sporadic seed production constrains restoration efforts and complicates sustainable management of this species....

  11. Animal production off grassland. | J.E. | African Journal of Range ...

    African Journals Online (AJOL)

    Potential grassland constitutes 37% of South Africa, 45% and 55% of this being sweet and sour respectively. The major factors limiting animal production in the sweetveld are a reduction in the grazing capacity of the veld through veld deterioration, and the fact that the stocking rates applied are in excess of the current ...

  12. Dynamic optimization of the complex adaptive controlling by the structure of enterprise’s product range

    Directory of Open Access Journals (Sweden)

    Andrey Fyodorovich Shorikov

    2013-06-01

    Full Text Available This paper reviews a methodical approach to solve multi-step dynamic problem of optimal integrated adaptive management of a product portfolio structure of the enterprise. For the organization of optimal adaptive terminal control of the system the recurrent algorithm, which reduces an initial multistage problem to the realization of the final sequence of problems of optimal program terminal control is offered. In turn, the decision of each problem of optimal program terminal control is reduced to the realization of the final sequence only single-step operations in the form of the problems solving of linear and convex mathematical programming. Thus, the offered approach allows to develop management solutions at current information support, which consider feedback, and which create the optimal structure of an enterprise’s product lines, contributing to optimising of profits, as well as maintenance of the desired level of profit for a long period of time

  13. Portable milk product quality analyzer based on spectrometry in the near IR range

    Science.gov (United States)

    Kalinin, A. V.; Krasheninnikov, V. N.

    2008-03-01

    We have used near IR spectrometry and multiple regression analysis to construct the calibration models for determining the weight fractions of the major components of milk blends, and we have used the latter to study the feasibility of using a portable spectrophotometer (designed at the Institute of Spectroscopy) based on a silicon CCD linear array as a working tool for monitoring the quality of biotechnological products.

  14. Improved forage strategies for high-yielding dairy cows in Vietnam : report of a workshop

    NARCIS (Netherlands)

    Wouters, A.P.; Lee, van der J.

    2013-01-01

    This report presents results of the workshop "Improved forage strategies for high-yielding dairy cows in Vietnam" which was held with Vietnamese stakeholders on January 17-18, 2013 in Ho Chi Minh City as part of the project "Forage and Grass Production for Dairy Development in Vietnam" funded by the

  15. Anaerobic co-digestion of forage radish and dairy manure in complete mix digesters

    Science.gov (United States)

    Farmers are increasingly using forage radish as a winter cover crop to achieve multiple soil and environmental benefits. In this study, pilot-scale mixed digesters were used to quantify methane (CH4) and hydrogen sulfide (H2S) production when using forage radish, a sulfur-rich cover crop, as a co-d...

  16. Nutritional composition of a full diallel-crossed forage pearl millet of ...

    African Journals Online (AJOL)

    The productivity of local cattle depends mainly on the quality of forage they consume, the search of which induces conflicts between herdsmen and farmers. The objective of this study was to evaluate the nutritional quality of 'maiwa' Pennisetum glaucum, for forage, in Ibadan, Nigeria. Three inbred lines, namely, 25-2, 28-1 ...

  17. Effects of seeding rates on forage yield and quality of oat ( Avena ...

    African Journals Online (AJOL)

    Forage availability and quality during the dry and cool season is a major constraint to dairy development in the Highlands of Madagascar. The objective of the present study was to determine optimal seeding of oat and common vetch mixtures for increased production and quality of forage. The study was conducted under ...

  18. 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.

  19. Production traits of artificially and naturally hatched geese in intensive and free-range systems: I. Growth traits.

    Science.gov (United States)

    Boz, M A; Sarica, M; Yamak, U S

    2017-04-01

    1. This study investigated the effect of incubation type and production system on geese growth traits. 2. A total of 216 geese were either naturally (114) or artificially (102) hatched and reared in intensive or free-range production systems (4 replicates each) until 18 weeks of age. 3. Weights of naturally hatched goslings (NHG) were significantly higher than artificially hatched goslings (AHG) at 2 weeks (644 vs. 536 g); however, weights of AHG were significantly higher than NHG at both 6 weeks (3245 vs. 3010 g) and 18 weeks (5212 vs. 4353 g). 4. AHG had better feed conversion ratios (FCRs) than NHG (6.21 vs. 6.46 at 18 weeks). Feed consumption of naturally hatched geese was found higher in first 4 weeks when compared to artificially hatched geese and artificially hatched geese consumed more feed than naturally hatched geese after 8 weeks. 5. Production system had insignificant effects on feed consumption, FCRs, viability and mutilation rates. 6. Slipped wings were more frequent in NHG than AHG (8.32% vs. 1.68% at 6 weeks; 23.84% vs. 5.12% between 7 and 18 weeks) and in free-range production when compared to intensive production (17.88% vs. 11.08% over the course of the production period). 7. The study results indicate that both artificially and NHG can be reared in free-range production systems without any loss in performance and in deference to animal welfare.

  20. Fatty acid composition of forage herb species

    DEFF Research Database (Denmark)

    Warner, D.; Jensen, Søren Krogh; Cone, J.W.

    2010-01-01

    The use of alternative forage species in grasslands for intensive livestock production is receiving renewed attention. Data on fatty acid composition of herbs are scarce, so four herbs (Plantago lanceolata, Achillea millefolium, Cichorium intybus, Pastinaca sativa) and one grass species (timothy......, Phleum pratense) were sown in a cutting trial. The chemical composition and concentration of fatty acids (FA) of individual species were determined during the growing season. Concentrations of crude protein and FA were generally higher in the herbs than in timothy. C. intybus had the highest nutritive...

  1. Are seabirds foraging for unpredictable resources?

    Science.gov (United States)

    Weimerskirch, Henri

    2007-02-01

    It is generally assumed that the extreme life history traits of pelagic seabirds, such as low fecundity or slow growth of chicks, result from the difficulties obtaining energy at sea from unpredictable and patchily distributed resources. However, little information on seabird prey distribution and availability exists to sustain this widely accepted hypothesis. Using tracking studies of 68 sub-populations of flying seabirds, I examine whether it is possible to gain information on the predictability of their marine resources. Because prey are clustered from fine to large scale in nested unities, from swarms to patches and concentrations of patches, it is important to take into account spatial scale. In temperate and polar regions, at large and meso-scales, seabirds appear to have a good knowledge of the location and concentrations of patches and generally use a commuting type of trip to reach foraging zones. Predictability appears to be high at large and meso-scales, with individuals from each sub-population heading in a particular direction from the colony to reach favoured habitats of known enhanced productivity such as shelf edges, frontal zones, upwellings. Within these mesoscale features, the animals use an area-restricted search behaviour to search for patches and swarms at finer scales. Using information on foraging site fidelity of individual birds, I show that differences in predictability at coarse scales are related to the distance and time spent foraging, and in particular to the specific types of foraging habitat. Some habitats appear to be more predictable than others: birds return consistently to the same coarse-scale sectors on shelf edges, whereas predictability is low in oceanic waters, even in frontal zones. Preliminary results on tropical species suggest that the environment here is less predictable in tropic than in temperate or polar zones. This review highlights that patchiness and predictability of marine resources are complex notions

  2. Range, energy loss, energy straggling and damage production for [alpha]-particles in uranium dioxide

    Science.gov (United States)

    Matzke, Hj.

    Energy loss and energy straggling of α-particles in UO 2 were measured for α-energies up to 8.78 MeV. α-sources of Pu-239 and a `multi-energy source' emitting α-particles of five different energies obtained by recoil implantation from a Th-228 source were coated with UO 2 layers of 17 different thicknesses. Confirmation of these results was obtained from Rutherford backscattering spectroscopy, RBS/channeling experiments with UO 2 single crystals preimplanted with He-ions. The measured energy loss values were used to deduce the range-energy relation. The results are in good agreement with calculations using the code TRIM 96. The energy straggling results are discussed in the frame of Bohr's theory. Finally, defects and damage produced by α-particles and He-ions in UO 2 are briefly treated.

  3. Preliminary Products of Precise Orbit Determination Using Satellite Laser Ranging Observations for ILRS AAC

    Directory of Open Access Journals (Sweden)

    Young-Rok Kim

    2012-09-01

    Full Text Available In this study, we present preliminary results of precise orbit determination (POD using satellite laser ranging (SLR observations for International Laser Ranging Service (ILRS Associate Analysis Center (AAC. Using SLR normal point observations of LAGEOS-1, LAGEOS-2, ETALON-1, and ETALON-2, the NASA/GSFC GEODYN II software are utilized for POD. Weekly-based orbit determination strategy is applied to process SLR observations and the post-fit residuals check, and external orbit comparison are performed for orbit accuracy assessment. The root mean square (RMS value of differences between observations and computations after final iteration of estimation process is used for post-fit residuals check. The result of ILRS consolidated prediction format (CPF is used for external orbit comparison. Additionally, we performed the precision analysis of each ILRS station by post-fit residuals. The post-fit residuals results show that the precisions of the orbits of LAGEOS-1 and LAGEOS-2 are 0.9 and 1.3 cm, and those of ETALON-1 and ETALON-2 are 2.5 and 1.9 cm, respectively. The orbit assessment results by ILRS CPF show that the radial accuracies of LAGEOS-1 and LAGEOS-2 are 4.0 cm and 5.3 cm, and the radial accuracies of ETALON-1 and ETALON-2 are 30.7 cm and 7.2 cm. These results of station precision analysis confirm that the result of this study is reasonable to have implications as preliminary results for administrating ILRS AAC.

  4. Variation in Biomass Composition Components among Forage, Biomass, Sorghum-Sudangrass, and Sweet Sorghum Types

    Energy Technology Data Exchange (ETDEWEB)

    Stefaniak, T. R.; Dahlberg, J. A.; Bean, B. W.; Dighe, N.; Wolfrum, E. J.; Rooney, W. L.

    2012-07-01

    Alternative biomass sources must be developed if the United States is to meet the goal in the U.S. Energy Security Act of 2007 to derive 30% of its petroleum from renewable sources, and several different biomass crops are currently in development. Sorghum [Sorghum bicolor (L.) Moench] is one such crop that will be an important feedstock source for biofuel production. As composition influences productivity, there exists a need to understand the range in composition observed within the crop. The goal of this research was to assess the range in dietary fiber composition observed within different types of biomass sorghums. A total of 152 sorghum samples were divided into the four end-use types of sorghum: biomass, forage, sorghum-sudangrass, and sweet. These samples were analyzed chemically using dietary fiber analysis performed at the National Renewable Energy Laboratory using published protocols. Significant variation among the groups was detected for glucan and ash. Positive and highly significant correlations were detected between structural carbohydrates in the biomass and sweet sorghums while many of these correlations were negative or not significant in the forage and sorghum-sudangrass types. In addition, a wide range of variation was present within each group indicating that there is potential to manipulate the composition of the crop.

  5. Relationship Between Forage Allowance and Grazing Efficiency in the Great Plains: Implications for Managing Rangelands for Both Livestock Production and Desired Ecosystem Goods and Services

    Science.gov (United States)

    Emergence of desired ecosystem goods and services from rangelands as a societal benefit and a potential income source for land managers has implications regarding the management of plant communities traditionally used primarily for livestock production. Contemporary decision-making on rangelands in ...

  6. Prevalence and sources of Campylobacter spp. contamination in free-range broiler production in the southern part of Belgium

    Directory of Open Access Journals (Sweden)

    Vandeplas, S.

    2010-01-01

    Full Text Available A one year epidemiological study was carried out between February 2005 and February 2006 in the southern part of Belgium to assess the Campylobacter prevalence in free-range broiler production. Three successive broiler flocks from six Belgian farms were investigated for the presence of Campylobacter spp. during the rearing period. Each flock was visited four times, before and after the outdoor rearing period. During each visit, samples were taken in the broiler house (litter, cecal droppings, water-lines, feed, anteroom as well as from the outer rearing environment (open-air range. The Campylobacter detection in all samples was carried out according to the ISO 10272 standard. Identification was based on colonial morphology, microscopic examination, and biochemical tests. PCR multiplex was used for genetic confirmation. Campylobacter jejuni was the main species isolated from all contaminated samples. Overall, mixed infections C. jejuni / Campylobacter coli represented 40.6%, while C. jejuni and C. coli represented 46.9% and 12.5% of chicken samples respectively. A 100% flock contamination was observed in the 6 farms during the summer-autumn period, whereas only 66.7% and 33.3% of the flocks became Campylobacter-positive in spring and winter respectively, at the end of the rearing period. Half of contaminated flocks were infected before chickens have access to the open-air range. Environmental samples, especially the open-air range soil, were found to be Campylobacter-positive before flock infection. The other potential sources of contamination were delivery tray, anteroom floor and water-lines. Other animal productions like cattle on the farm, no applied rodent control, no cleaning and disinfection of water-lines between flocks, no detergent used for cleaning and thinning were recorded as risk factors. In conclusion, the contact with the environment, particularly the access to an open-air range, appeared to be the major way of Campylobacter

  7. A Breath of Fresh Air in Foraging Theory: The Importance of Wind for Food Size Selection in a Central-Place Forager.

    Science.gov (United States)

    Alma, Andrea Marina; Farji-Brener, Alejandro G; Elizalde, Luciana

    2017-09-01

    Empirical data about food size carried by central-place foragers do not often fit with the optimum predicted by classical foraging theory. Traditionally, biotic constraints such as predation risk and competition have been proposed to explain this inconsistency, leaving aside the possible role of abiotic factors. Here we documented how wind affects the load size of a central-place forager (leaf-cutting ants) through a mathematical model including the whole foraging process. The model showed that as wind speed at ground level increased from 0 to 2 km/h, load size decreased from 91 to 30 mm2, a prediction that agreed with empirical data from windy zones, highlighting the relevance of considering abiotic factors to predict foraging behavior. Furthermore, wind reduced the range of load sizes that workers should select to maintain a similar rate of food intake and decreased the foraging rate by ∼70% when wind speed increased 1 km/h. These results suggest that wind could reduce the fitness of colonies and limit the geographic distribution of leaf-cutting ants. The developed model offers a complementary explanation for why load size in central-place foragers may not fit theoretical predictions and could serve as a basis to study the effects of other abiotic factors that influence foraging.

  8. Sublethal imidacloprid effects on honey bee flower choices when foraging.

    Science.gov (United States)

    Karahan, Ahmed; Çakmak, Ibrahim; Hranitz, John M; Karaca, Ismail; Wells, Harrington

    2015-11-01

    Neonicotinoids, systemic neuro-active pesticides similar to nicotine, are widely used in agriculture and are being investigated for a role in honey bee colony losses. We examined one neonicotinoid pesticide, imidacloprid, for its effects on the foraging behavior of free-flying honey bees (Apis mellifera anatoliaca) visiting artificial blue and white flowers. Imidacloprid doses, ranging from 1/5 to 1/50 of the reported LD50, were fed to bees orally. The study consisted of three experimental parts performed sequentially without interruption. In Part 1, both flower colors contained a 4 μL 1 M sucrose solution reward. Part 2 offered bees 4 μL of 1.5 M sucrose solution in blue flowers and a 4 μL 0.5 M sucrose solution reward in white flowers. In Part 3 we reversed the sugar solution rewards, while keeping the flower color consistent. Each experiment began 30 min after administration of the pesticide. We recorded the percentage of experimental bees that returned to forage after treatment. We also recorded the visitation rate, number of flowers visited, and floral reward choices of the bees that foraged after treatment. The forager return rate declined linearly with increasing imidacloprid dose. The number of foraging trips by returning bees was also affected adversely. However, flower fidelity was not affected by imidacloprid dose. Foragers visited both blue and white flowers extensively in Part 1, and showed greater fidelity for the flower color offering the higher sugar solution reward in Parts 2 and 3. Although larger samples sizes are needed, our study suggests that imidacloprid may not affect the ability to select the higher nectar reward when rewards were reversed. We observed acute, mild effects on foraging by honey bees, so mild that storage of imidacloprid tainted-honey is very plausible and likely to be found in honey bee colonies.

  9. Effects of diet forage source and neutral detergent fiber content on milk production of dairy cattle and methane emissions determined using GreenFeed and respiration chamber techniques.

    Science.gov (United States)

    Hammond, K J; Jones, A K; Humphries, D J; Crompton, L A; Reynolds, C K

    2016-10-01

    Strategies to mitigate greenhouse gas emissions from dairy cattle are unlikely to be adopted if production or profitability is reduced. The primary objective of this study was to examine the effects of high maize silage (MS) versus high grass silage (GS) diets, without or with added neutral detergent fiber (NDF) on milk production and methane emission of dairy cattle, using GreenFeed (GF) or respiration chamber (RC) techniques for methane emission measurements. Experiment 1 was 12wk in duration with a randomized block continuous design and 40 Holstein cows (74d in milk) in free-stall housing, assigned to 1 of 4 dietary treatments (n=10 per treatment), according to calving date, parity, and milk yield. Milk production and dry matter intake (DMI) were measured daily, and milk composition measured weekly, with methane yield (g/kg of DMI) estimated using a GF unit (wk 10 to 12). Experiment 2 was a 4×4 Latin square design with 5-wk periods and 4 dairy cows (114d in milk) fed the same 4 dietary treatments as in experiment 1. Measurements of DMI, milk production, and milk composition occurred in wk 4, and DMI, milk production, and methane yield were measured for 2d in RC during wk 5. Dietary treatments for both experiments were fed as total mixed rations offered ad libitum and containing 500g of silage/kg of dry matter composed (DM basis) of either 75:25 MS:GS (MS) or 25:75 MS:GS (GS), without or with added NDF from chopped straw and soy hulls (+47g of NDF/kg of dry matter). In both experiments, compared with high GS, cows fed high MS had a higher DMI, greater milk production, and lower methane yield (24% lower in experiment 1 using GF and 8% lower in experiment 2 using RC). Added NDF increased (or tended to increase) methane yield for high MS, but not high GS diets. In the separate experiments, the GF and RC methods detected similar dietary treatment effects on methane emission (expressed as g/d and g/kg of DMI), although the magnitude of the differences varied between

  10. 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

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

    Directory of Open Access Journals (Sweden)

    Marianna Chimienti

    2014-09-01

    Full Text Available 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

  12. Ruminal silage degradability and productivity of forage and grain-type sorghum cultivars Degradabilidade ruminal das silagens e produtividade de cultivares de sorgo de tipo forrageiro e granífero

    Directory of Open Access Journals (Sweden)

    José Antônio Resende

    2003-01-01

    Full Text Available Forages for feeding dairy cows should conciliate the potential for high dry matter yield per unit area, maximizing animal stocking rate, with high nutritive value, which enables decreasing the amount of concentrate feedstuffs per milk unit produced. Eighteen sorghum cultivars were cultivated 0.70 m apart and with 12 plants per linear meter. Plants harvested at the milk-to-dough stage were ensiled in the laboratory. Eleven agronomic and chemical traits were evaluated. Silage samples were incubated in situ and the effective ruminal dry matter degradation (DEF was calculated assuming a fractional passage rate of -0.04 h-1. Dry matter yield was 13.0 ± 2.3 (mean ± S.D. t ha-1. The neutral detergent fiber content was 50.3 ± 3.8 and the DEF was 48.8 ± 2.8% (dry matter basis. The average sorghum DEF was 84% of the DEF of a composite sample of 60 corn hybrids simultaneously cultivated, ensiled and ruminally incubated. The 12 forage-type cultivars were taller, more productive, had higher fiber content and lower DEF than the 6 grain and dual purpose-type cultivars. The acid detergent fiber content had the greatest correlation with DEF (r= -0.64. The linear model correlating DEF with productivity was: DEF=54.694 - 0.4449 x t of dry matter ha-1 (r²=0.14. Although there are cultivars that show high productivity and digestibility, it seems to be difficult to conciliate the maximum nutritive value with the maximum productivity of the sorghum crop.Forrageiras para alimentação de vacas leiteiras devem conciliar a alta produção de matéria seca por área, maximizando a taxa de lotação animal, com o alto valor nutritivo, capaz de reduzir a necessidade de alimentos concentrados por litro de leite produzido. Dezoito cultivares de sorgo foram cultivados com espaçamento de 0,70 m e 12 plantas por metro linear. As plantas colhidas ao atingirem o estádio leitoso-pastoso foram ensiladas em laboratório. Onze características agronômicas e químicas foram

  13. Plot showing ATLAS limits on Standard Model Higgs production in the mass range 100-600 GeV

    CERN Multimedia

    ATLAS Collaboration

    2011-01-01

    The combined upper limit on the Standard Model Higgs boson production cross section divided by the Standard Model expectation as a function of mH is indicated by the solid line. This is a 95% CL limit using the CLs method in the entire mass range. The dotted line shows the median expected limit in the absence of a signal and the green and yellow bands reflect the corresponding 68% and 95% expected

  14. Plot showing ATLAS limits on Standard Model Higgs production in the mass range 110-150 GeV

    CERN Multimedia

    ATLAS Collaboration

    2011-01-01

    The combined upper limit on the Standard Model Higgs boson production cross section divided by the Standard Model expectation as a function of mH is indicated by the solid line. This is a 95% CL limit using the CLs method in in the low mass range. The dotted line shows the median expected limit in the absence of a signal and the green and yellow bands reflect the corresponding 68% and 95% expected

  15. Spectral range optimization for the near-infrared quantitative analysis of petrochemical and petroleum products: naphtha and gasoline.

    Science.gov (United States)

    Lee, Youngbok; Chung, Hoeil; Kim, Nakjoong

    2006-08-01

    The proper selection of the spectral range in partial least squares (PLS) calibration is critical when highly overlapping spectra from compositionally complex samples are used, such as naphtha and gasoline. In particular, the relevant spectral information related to a given property is frequently localized in a narrow range, and the most selective region may be difficult to locate. We have presented the importance of range optimization in near-infrared (NIR) spectroscopy for the analyses of petrochemical and petroleum products that are generally highly complex in composition. For this purpose, the determination of a detailed compositional analysis (so called PIONA) and the distillation temperature of naphtha were evaluated. In the same fashion, the research octane number (RON) and Reid vapor pressure (RVP) were selected for gasoline. By optimizing the range using moving window (MW) PLS, the overall calibration performance was improved by finding the optimal spectral range for each property. In particular, for a detailed compositional analysis of naphtha, it was effective to search for localized spectral information in a relatively narrow range with fewer factors.

  16. 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...

  17. Notes on foraging activity of female Myotis leibii in Maryland

    Science.gov (United States)

    Joshua B. Johnson; J. Edward Gates; W. Mark Ford

    2009-01-01

    Information on home range and habitat characteristics of eastern small-footed myotis (Myotis leibii) consist only of anecdotal accounts and unpublished research despite the need for such data for conservation of this rare species. We used radio telemetry to determine foraging site selection of four female eastern small-footed myotis in Allegany...

  18. Intestinal digestibility of protein of adapted forages and by-products in Brazilian Northeast by three-steps technique Digestão intestinal da proteína de forrageiras e co-produtos da agroindústria produzidos no Nordeste Brasileiro por intermédio da técnica de três estágios

    Directory of Open Access Journals (Sweden)

    José Gilson Lousada Regadas Filho

    2010-06-01

    Full Text Available It was aimed to estimate the intestinal digestibility (ID of rumen-undegradable protein (RUDP of several feeds by a three-steps procedure. The evaluated forages were algaroba (Prosopis juliflora, canafístula (Pithecellobium multiflorum, flor-de-seda (Calotropis procera, jitirana (Ipomea sp., juazeiro (Ziziphus joazeiro, mata-pasto (Senna obtusifolia, sabiá (Mimosa caesalpiniaefolia Benth, palma gigante (Opuntia ficus indica and xique-xique (Cereus gounellei, and the agroindustry byproducts were pineapple (Ananas comosus L., barbados cherry (Malpighia emarginata, cashew (Anacardium occidentale, coconut (Cocos nucifera L., melon (Cucumis melo, passion fruit (Passiflora eduli, grape (Vitis labrusca and anatto seeds (Bixa orellana L.. The feeds were incubated in rumen during 16 hours to determine the RUDP, and the residue was submitted to the digestion with pepsin solution during one hour, and pancreatic solution during 24 hours at 38ºC, those residues were analyzed for total nitrogen. The estimative of RUDP forage ranged from 13.37 to 83.6%, and the RUDP by-product ranged from 39.14 to 89.06%. The intestinal digestion of RUDP of the forages ranged from 26.09 to 80.68%, while for by-products varied from 22.26 to 76.82%. The sabiá was the forage that presented the highest intestinal digestibility and digestive rumen-undegradable protein (RUDPd, and the flor-de-seda, the lowest digestibility; while for by-products, melon and cashew presented, respectively, the highest values for DI and RUDP. The coconut presented the lowest values for ID and RUDPd. Although, some formulation systems of diets for ruminant consider that the RUDP present constant ID, the data obtained in this work suggest variation among the different feeds.A pesquisa objetivou estimar a digestibilidade intestinal (DI da proteína não-degradada no rúmen (PNDR de alimentos por intermédio da técnica de três estágios. As forragens avaliadas foram algaroba (Prosopis juliflora

  19. 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.

  20. Development of Oscillating Classifiers for Forage Chop Length ...

    African Journals Online (AJOL)

    The chop length produced by forage harvesting systems is an important factor in many aspects of silage production. The only reliable method being tedious hand measurement of every particle in a sample of chopped material. Three oscillating particle length classifiers have been developed. Each of them differed from one ...

  1. Forage yield and soil improvement potential of some annual and ...

    African Journals Online (AJOL)

    Six annual and semi-perennial legumes were evaluated for forage production and their effect on soil properties at two sites, Pokoase (transition zone) and Nyankpala (Guinea savanna zone). The common legumes evaluated at the two sites were Lablab purpureus, Desmodium distortum, Crotalaria ochroleuca, and ...

  2. Nutritive value response of forage chicory cultivars to phosphorus fertility

    Science.gov (United States)

    Forage chicory (Cichorium intybus L.) is a productive plant that appears particularly well suited to improving summer yield of pastures in the USA. Poor palatability of some chicory cultivars in locations with low soil phosphorus fertility has been linked to high levels of sesquiterpene lactones, b...

  3. Foraging behavior of egg parasitoids exploiting chemical information

    NARCIS (Netherlands)

    Fatouros, N.E.; Dicke, M.; Mumm, R.; Meiners, T.; Hilker, M.

    2008-01-01

    Female parasitic wasps seek hosts for their offspring often in a dynamic environment. Foraging egg parasitoids rely on a variety of chemical cues originating from the adult host, host products, or the host plant rather than from the attacked host stage¿the insect egg itself. Besides pupae, insect

  4. Response Of Three Forage Legumes To Soil Moisture Stress ...

    African Journals Online (AJOL)

    The mean P content of the plants decreased with decreasing soil moisture content while, that of K increased as moisture stress increased. The overall plant performance pointed to Centrosema as a more favoured for-age plant for dry environments . Keywords: Crop productivity, legumes, food security, water use efficiency ...

  5. Foraging task specialisation and foraging labour allocation in stingless bees

    NARCIS (Netherlands)

    Hofstede, Frouke Elisabeth

    2006-01-01

    Social bees collect nectar and pollen from flowering plants for energy of the adult bees and for feeding the larvae in the colony. The flowering patterns of plants imply that periods of high food availability are often followed by periods of meagre foraging conditions. Being dependent on such a

  6. Forage polyphenol oxidase and ruminant livestock nutrition

    Science.gov (United States)

    Lee, Michael R. F.

    2014-01-01

    Polyphenol oxidase (PPO) is predominately associated with the detrimental effect of browning fruit and vegetables, however, interest within PPO containing forage crops (crops to be fed to animals) has grown since the browning 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 [feed N into product N (e.g., Milk): NUE] when fed to ruminants. A further benefit of red clover silage feeding is a significant reduction in lipolysis (cleaving of glycerol-based lipid) 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 catalyzing 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 (e.g., protease or lipase) 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 undegraded dietary protein flow to the small intestine. The mechanism for protecting glycerol-based PUFA has yet to be fully elucidated but may be associated

  7. Forage polyphenol oxidase and ruminant livestock nutrition.

    Science.gov (United States)

    Lee, Michael R F

    2014-01-01

    Polyphenol oxidase (PPO) is predominately associated with the detrimental effect of browning fruit and vegetables, however, interest within PPO containing forage crops (crops to be fed to animals) has grown since the browning 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 [feed N into product N (e.g., Milk): NUE] when fed to ruminants. A further benefit of red clover silage feeding is a significant reduction in lipolysis (cleaving of glycerol-based lipid) 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 catalyzing 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 (e.g., protease or lipase) 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 undegraded dietary protein flow to the small intestine. The mechanism for protecting glycerol-based PUFA has yet to be fully elucidated but may be associated

  8. 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

  9. 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

  10. Effects of season, browse species and polyethylene glycol addition on gas production kinetics of forages in the subhumid subtropical savannah, South Africa.

    Science.gov (United States)

    Basha, Nasreldin A D; Scogings, Peter F; Nsahlai, Ignatius V

    2013-04-01

    This study was conducted to investigate the effects of season, species and polyethylene glycol addition on gas production (GP) and GP kinetic parameters by in vitro incubation (72 h) of five plant species from the subhumid subtropical savannah, South Africa. Plant species used were Acacia natalitia, Acacia nilotica, Dichrostachys cinerea, Scutia myrtina and Chromolaena odorata, leaves of which were harvested during the dry (June/July), early wet (November/December) and late wet (February/March) seasons. An automated in vitro gas production technique was used in two experiments carried out with nine replicates. The first experiment was to test the effect of season and species, while the second experiment tested the effect of tannins using polyethylene glycol 4000 (PEG). The PEG treatment was applied to samples in the early wet and late wet seasons. There were wide variations among seasons and species in crude protein (CP), neutral detergent fibre (NDF), acid detergent fibre (ADF) and condensed tannin (CT). Season and species affected the maximum GP and GP kinetic parameters. During the three seasons, C. odorata had the highest CP (186-226 g kg(-1) dry matter (DM)) and GP (87-104 mL g(-1) DM) and S. myrtina had the lowest CP (105-129 g kg(-1) DM), while A. nilotica, A. natalitia, D. cinerea and S. myrtina had similar and low GP (23-50 mL g(-1) DM). The maximum GP, its degradation rate and GP from the soluble fraction were positively correlated with CP both without and with PEG. With PEG, GP from the soluble fraction was negatively correlated with NDF, ADL and CT; without PEG, it was negatively correlated with CT. Both season and species affected the GP parameters. The addition of PEG emphasises that the inhibitory effect of tannins on rumen microbes was greater for all but C. odorata, confirming that these browse species can be used as feed supplements. © 2012 Society of Chemical Industry.

  11. Egg production and egg quality in free-range laying hens housed at different outdoor stocking densities.

    Science.gov (United States)

    Campbell, D L M; Lee, C; Hinch, G N; Roberts, J R

    2017-09-01

    Free-range laying hen systems are increasing in number within Australia. Variation in outdoor stocking densities has led to development of a national information standard on free-range egg labeling, including setting a maximum density of 10,000 hens per hectare. However, there are few data on the impacts of differing outdoor densities on production and egg quality. ISA Brown hens in small (150 hens) flocks were housed in identical indoor pens, each with access (from 21 weeks) to different sized ranges simulating one of three outdoor stocking densities (2 replicates each: 2,000 hens/hectare (ha), 10,000 hens/ha, 20,000 hens/ha). Hen-day production was tracked from 21 through 35 weeks with eggs visually graded daily for external deformities. All eggs laid on one day were weighed each week. Eggs were collected from each pen at 25, 30, and 36 weeks and analyzed for egg quality. There were no effects of outdoor stocking density on average hen-day percentage production (P = 0.67), egg weight (P = 0.09), percentages of deformed eggs (P = 0.30), shell reflectivity (P = 0.74), shell breaking strength (P = 0.07), shell deformation (P = 0.83), or shell thickness (P = 0.24). Eggs from hens in the highest density had the highest percentage shell weight (P = 0.004) and eggs from the lowest density had the highest yolk color score (P < 0.001). The amount of cuticle present did not differ between densities (P = 0.95) but some aspects of shell colors (P ≤ 0.01) and location of protoporphyrin IX (P = 0.046) varied. Hen age affected the majority of measurements. Stocking density differences may be related to hen diet as previous radio-frequency identification tracking of individual hens in these flocks showed birds used the range for longer in the lowest density and the least in the highest density, including depleting the range of vegetation sooner in the smaller ranges. An additional study assessing the relationship between individual hen range use, nutrition, and egg

  12. Complex scaling behavior in animal foraging patterns

    Science.gov (United States)

    Premachandra, Prabhavi Kaushalya

    This dissertation attempts to answer questions from two different areas of biology, ecology and neuroscience, using physics-based techniques. In Section 2, suitability of three competing random walk models is tested to describe the emergent movement patterns of two species of primates. The truncated power law (power law with exponential cut off) is the most suitable random walk model that characterizes the emergent movement patterns of these primates. In Section 3, an agent-based model is used to simulate search behavior in different environments (landscapes) to investigate the impact of the resource landscape on the optimal foraging movement patterns of deterministic foragers. It should be noted that this model goes beyond previous work in that it includes parameters such as spatial memory and satiation, which have received little consideration to date in the field of movement ecology. When the food availability is scarce in a tropical forest-like environment with feeding trees distributed in a clumped fashion and the size of those trees are distributed according to a lognormal distribution, the optimal foraging pattern of a generalist who can consume various and abundant food types indeed reaches the Levy range, and hence, show evidence for Levy-flight-like (power law distribution with exponent between 1 and 3) behavior. Section 4 of the dissertation presents an investigation of phase transition behavior in a network of locally coupled self-sustained oscillators as the system passes through various bursting states. The results suggest that a phase transition does not occur for this locally coupled neuronal network. The data analysis in the dissertation adopts a model selection approach and relies on methods based on information theory and maximum likelihood.

  13. 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.

  14. Effects of the juvenile hormone analogue methoprene on rate of behavioural development, foraging performance and navigation in honey bees (Apis mellifera).

    Science.gov (United States)

    Chang, Lun-Hsien; Barron, Andrew B; Cheng, Ken

    2015-06-01

    Worker honey bees change roles as they age as part of a hormonally regulated process of behavioural development that ends with a specialised foraging phase. The rate of behavioural development is highly plastic and responsive to changes in colony condition such that forager losses, disease or nutritional stresses accelerate behavioural development and cause an early onset of foraging in workers. It is not clear to what degree the behavioural development of workers can be accelerated without there being a cost in terms of reduced foraging performance. Here, we compared the foraging performance of bees induced to accelerate their behavioural development by treatment with the juvenile hormone analogue methoprene with that of controls that developed at a normal rate. Methoprene treatment accelerated the onset of both flight and foraging behaviour in workers, but it also reduced foraging span, the total time spent foraging and the number of completed foraging trips. Methoprene treatment did not alter performance in a short-range navigation task, however. These data indicate a limitation to the physiological plasticity of bees, and a trade off between forager performance and the speed at which bees begin foraging. Chronic stressors will be expected to reduce the mean age of the foraging force, and therefore also reduce the efficiency of the foraging force. This interaction may explain why honey bee colonies react to sustained stressors with non-linear population decline. © 2015. Published by The Company of Biologists Ltd.

  15. 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.

  16. Métodos de plantio de gliricídia (Gliricidia sepium (Jacq. Walp. em estacas para produção de forragem Establishment methods of gliricidia (Gliricidia sepium (Jacq. Walp. from stakes for forage production

    Directory of Open Access Journals (Sweden)

    Benedito Marques da Costa

    2004-12-01

    Full Text Available Gliricídia, uma leguminosa arbórea utilizada no sombreamento de cacaueiros e na produção de forragem, é comumente empregada como cerca viva, madeira e lenha e pode ser multiplicada por sementes e por frações do caule ou de estacas. Conduziu-se este estudo na Escola de Agronomia da UFBA, em Cruz das Almas - Bahia, com o objetivo de avaliar métodos de plantio por estaquia, a fim de se identificar aquele de maior índice de pegamento das estacas, maior produção de forragem e menor custo de implantação. O delineamento experimental foi em blocos casualizados, com cinco tratamentos e cinco repetições. Os tratamentos foram os seguintes: 1 estacas de 1 m de comprimento plantadas verticalmente em covas; 2 estacas de 0,5 m de comprimento plantadas verticalmente em covas; 3 estacas de 0,25 m de comprimento plantadas verticalmente em covas; 4 estacas de 1 m de comprimento plantadas horizontalmente dentro do sulco; 5 estacas de 0,5 m de comprimento plantadas horizontalmente dentro sulco. As estacas de 1,0 m de comprimento plantadas verticalmente dentro de covas (método 1 ou horizontalmente dentro de sulcos (método 4, após 14 dias de colhidas, são os métodos mais recomendáveis por apresentarem menores custos na preparação das estacas e operações de plantio, proporcionando melhores lucros por hectare quando consideradas as receitas das produções de matéria seca.Gliricidia sepium has been used as shade tree in cocoa plantations, living fences, wood, fuel wood and livestock forage. It can be grown from seeds and from cuttings or stakes. This experiment was carried out to evaluate five grown methods from Gliricidia cuttings in other to identify the one showing highest stake sprouting indexes, forage production and least implantation costs. The experiment was in a randomized block design with five treatments and five replications. The treatments were the followings: 1 stakes with 1m in length placed vertically in pits; 2 stakes with .5 m

  17. 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.

  18. 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

    2015-05-01

    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.

  19. 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

  20. Novel forages for growth and health in farmed deer.

    Science.gov (United States)

    Barry, T N; Hoskin, S O; Wilson, P R

    2002-12-01

    This paper reviews recent research on the use of new forages in deer farming that may be useful for increasing growth in weaner deer for venison production, increasing the trace element status of deer, and for developing systems less reliant on chemical inputs, notably of anthelmintics used to control internal parasites. Grazing on pure swards of red clover (Trifolium pratense) or chicory (Chicorium intybus) increased weaner growth during autumn by 26-47% and during spring by 10-14%, relative to red deer (Cervus elaphus) grazed on perennial ryegrass (Lolium perenne) /white clover (Trifolium repens) pasture (0.8/0.2). Pre-weaning growth during lactation was increased by approximately 20%. These increases were due to increased rate of degradation of feed particles in the rumen, leading to higher digestibility and higher voluntary feed intakes (VFI). Red clover and chicory produce a greater proportion of their total dry matter (DM) during late summer and autumn than perennial ryegrass/white clover pastures, and are therefore better aligned with the seasonal feed requirements of deer. Grazing on the legume, sulla (Hedysarum coronarium), in autumn and spring increased the growth of weaner deer by 33% and 10%, respectively, relative to pasture-fed animals. Plants containing substantial concentrations of secondary compounds such as condensed tannins (CT) show promise for reducing problems caused by internal parasites. CT present in some legumes and the presence of low concentrations of both CT and sesquiterpene lactones in chicory are reviewed. Feeding sulla containing 35g CT /kg DM reduced abomasal nematode establishment and tended to reduce lungworm (Dictyocaulis eckerti) larval counts in faeces. Relative to weaner deer grazing pasture, weaner deer grazing chicory during autumn required fewer anthelmintic treatments without depressing growth rates. CT extracted from a range of legumes, and CT and sesquiterpene lactones extracted from chicory reduced the in vitro

  1. An evaluation of the accuracy and precision of methane prediction equations for beef cattle fed high-forage and high-grain diets.

    Science.gov (United States)

    Escobar-Bahamondes, P; Oba, M; Beauchemin, K A

    2017-01-01

    The study determined the performance of equations to predict enteric methane (CH4) from beef cattle fed forage- and grain-based diets. Many equations are available to predict CH4 from beef cattle and the predictions vary substantially among equations. The aims were to (1) construct a database of CH4 emissions for beef cattle from published literature, and (2) identify the most precise and accurate extant CH4 prediction models for beef cattle fed diets varying in forage content. The database was comprised of treatment means of CH4 production from in vivo beef studies published from 2000 to 2015. Criteria to include data in the database were as follows: animal description, intakes, diet composition and CH4 production. In all, 54 published equations that predict CH4 production from diet composition were evaluated. Precision and accuracy of the equations were evaluated using the concordance correlation coefficient (r c ), root mean square prediction error (RMSPE), model efficiency and analysis of errors. Equations were ranked using a combined index of the various statistical assessments based on principal component analysis. The final database contained 53 studies and 207 treatment means that were divided into two data sets: diets containing ⩾400 g/kg dry matter (DM) forage (n=116) and diets containing ⩽200 g/kg DM forage (n=42). Diets containing between ⩽400 and ⩾200 g/kg DM forage were not included in the analysis because of their limited numbers (n=6). Outliers, treatment means where feed was fed restrictively and diets with CH4 mitigation additives were omitted (n=43). Using the high-forage dataset the best-fit equations were the International Panel on Climate Change Tier 2 method, 3 equations for steers that considered gross energy intake (GEI) and body weight and an equation that considered dry matter intake and starch:neutral detergent fiber with r c ranging from 0.60 to 0.73 and RMSPE from 35.6 to 45.9 g/day. For the high-grain diets, the 5 best

  2. Biomass production, forage quality, and cation uptake of Quail bush, four-wing saltbush, and seaside barley irrigated with moderately saline-sodic water

    Energy Technology Data Exchange (ETDEWEB)

    Bauder, J.W.; Browning, L.S.; Phelps, S.D.; Kirkpatrick, A.D. [Montana State University, Bozeman, MT (United States)

    2008-07-01

    The study reported here investigated capacity of Atriplex lentiformis (Torr.) S. Wats. (Quail bush), Atriplex X aptera A. Nels. (pro sp.) (Wytana four-wing saltbush), and Hordeum marinum Huds. (seaside barley) to produce biomass and crude protein and take up cations when irrigated with moderately saline-sodic water, in the presence of a shallow water table. Water tables were established at 0.38, 0.76, and 1.14m below the surface in sand-filled columns. The columns were then planted to the study species. Study plants were irrigated for 224 days; irrigation water was supplied every 7 days equal to water lost to evapotranspiration (ET) plus 100mL (the volume of water removed in the most previous soil solution sampling). Water representing one of two irrigation sources was used: Powder River (PR) or coalbed natural gas (CBNG) wastewater. Biomass production did not differ significantly between water quality treatments but did differ significantly among species and water table depth within species. Averaged across water quality treatments, Hordeum marinum produced 79% more biomass than A. lentiformis and 122% more biomass than Atriplex X aptera, but contained only 11% crude protein compared to 16% crude protein in A. lentiformis and 14% crude protein in Atriplex X aptera. Atriplex spp. grown in columns with the water table at 0.38m depth produced more biomass, took up less calcium on a percentage basis, and took up more sodium on a percentage basis than when grown with the water table at a deeper depth. Uptake of cations by Atriplex lentiformis was approximately twice the uptake of cations by Atriplex X aptera and three times that of H. marinum. After 224 days of irrigation, crop growth, and cation uptake, followed by biomass harvest, EC and SAR of shallow groundwater in columns planted to A. lentiformis were less than EC and SAR of shallow ground water in columns planted to either of the other species.

  3. Bumblebee foraging rhythms under the midnight sun measured with radiofrequency identification

    Directory of Open Access Journals (Sweden)

    Chittka Lars

    2010-06-01

    Full Text Available Abstract Background In the permanent daylight conditions north of the Arctic circle, there is a unique opportunity for bumblebee foragers to maximise intake, and therefore colony growth, by remaining active during the entire available 24-h period. We tested the foraging rhythms of bumblebee (Bombus terrestris and B. pascuorum colonies in northern Finland during the summer, when the sun stays above the horizon for weeks. We used fully automatic radio-frequency identification to monitor the foraging activity of more than 1,000 workers and analysed their circadian foraging rhythms. Results Foragers did not use the available 24-h foraging period but exhibited robust diurnal rhythms instead. A mean of 95.2% of the tested B. terrestris workers showed robust diurnal rhythms with a mean period of 23.8 h. Foraging activity took place mainly between 08:00 and 23:00, with only low or almost no activity during the rest of the day. Activity levels increased steadily during the morning, reached a maximum around midday and decreased again during late afternoon and early evening. Foraging patterns of native B. pascuorum followed the same temporal organisation, with the foraging activity being restricted to the period between 06:00 and 22:00. Conclusions The results of the present study indicate that the circadian clock of the foragers must have been entrained by some external cue, the most prominent being daily cycles in light intensity and temperature. Daily fluctuations in the spectral composition of light, especially in the UV range, could also be responsible for synchronising the circadian clock of the foragers under continuous daylight conditions.

  4. Foraging behavior and at-sea distribution of White-Tailed Tropicbirds in tropical ocean.

    Science.gov (United States)

    Campos, L F A S; Andrade, A B; Bertrand, S; Efe, M A

    2017-11-09

    We used miniaturized GPS loggers and site observations to access foraging patterns and nest behaviour of the White-tailed Tropicbird Phaethon lepturus (WTTB), an endangered species at its South Atlantic breeding colony. Dual foraging pattern was observed with alternation between long and short foraging trips. Birds responsible for nest attendance engaged in short foraging trips with mean distance from colony of 25 ± 17 km, total distance covered of 79 ± 65 km and mean duration of 4.02 ± 5.28 hours. Birds flew by dawn and returned before dusk while partners were at sea for long foraging trips that ranged from four to 11 days, with mean maximum distance from colony of 105 ± 47.48 km. Chicks were usually left alone for hours and chick predation by Land Crab Johngartia lagostroma, egg consumption by Goniopsis cruentata and intra-specific competition are suspected to be responsible for high chick mortality rates.

  5. Forages from intensively managed and semi-natural grasslands in the diet of dairy cows

    NARCIS (Netherlands)

    Bruinenberg, M.H.

    2003-01-01

    Keywords : Intensively managed grass, semi-natural grasslands, forage species, dairy cows, in vivo digestibility, feed degradation, energy metabolism, milk production, ruminant nutrition, rumen fermentation, rumen kinetics, voluntary intake, feed

  6. African Journal of Range and Forage Science - Vol 17 (2000)

    African Journals Online (AJOL)

    Estimation of the herbaceous standing crop of the grassy plains of 01 Choro Oiroua in the Masai Mara region of Kenya · EMAIL FULL TEXT EMAIL FULL TEXT DOWNLOAD FULL TEXT DOWNLOAD FULL TEXT. LD van Essen, JP Bothma, N van Rooyen, WSW Trollope ...

  7. African Journal of Range and Forage Science: Advanced Search

    African Journals Online (AJOL)

    Search tips: Search terms are case-insensitive; Common words are ignored; By default only articles containing all terms in the query are returned (i.e., AND is implied); Combine multiple words with OR to find articles containing either term; e.g., education OR research; Use parentheses to create more complex queries; e.g., ...

  8. African Journal of Range and Forage Science: Contact

    African Journals Online (AJOL)

    Support Contact. Susi Vetter Email: s.vetter@ru.ac.za. ISSN: 1022-0119. AJOL African Journals Online. HOW TO USE AJOL... for Researchers · for Librarians · for Authors · FAQ's · More about AJOL · AJOL's Partners · Terms and Conditions of Use · Contact AJOL · News. OTHER RESOURCES... for Researchers · for Journals ...

  9. Book Reviews | Slingsby | African Journal of Range and Forage ...

    African Journals Online (AJOL)

    The GEO Handbook on Biodiversity Observation Networks Edited by Michele Walters and Robert J Scholes 2017, Springer Open, Springer International Publishing AG, Gewerbestrasse 11, 6330 Cham, Switzerland 330 pages, hardcover and ebook ISBN 978-3-319-27286-3 (hardcover), 978-3-319-27288-7 (eBook).

  10. Short-range correlations in hadron pair production at p sub T >= 2GeV/c

    Energy Technology Data Exchange (ETDEWEB)

    Bellogianni, A.; Stassinaki, M.; Vassiliadis, G.; Vichou, I. (Athens Univ. (Greece). Dept. of Nuclear Physics); Benayoun, M.; Kahane, J.; Leruste, P.; Malamant, A.; Narjoux, J.L.; Safarik, K.; Sene, M.; Sene, R.; Volte, A. (College de France, 75 - Paris (France). Lab. de Physique Corpusculaire); Beusch, W.; French, B.R.; Jacholkowski, A.; Kirk, A.; Knudson, K.; Quereigh, E. (European Organization for Nuclear Research, Geneva (Switzerland)); Bloodworth, I.J.; Carney, J.N.; Kinson, J.B.; Trainor, M.T.; Villalobos Baille, O.; Vortruba, M.F. (Birmingham Univ. (United Kingdom). Dept. of Physics); Di Bari, D.; Fini, R.; Ghidini, B.; Lenti, V.; Navach, F.; Palano, A. (Bari Univ. (Italy). Ist. di Fisica Istituto Nazionale di Fisica Nucleare, Bari (Italy)); Zitoun, R. (Paris-6 Univ., 75 (France). Lab. de Physique Nucleaire et de Hautes Energies Paris-7 Univ., 75 (France). Lab. de Physique Experimentale des Hautes Energies); WA77 Collaboration

    1992-06-01

    Production of oppositely charged particle pairs at large p{sub T} is studied, where both particles are in the central rapidity region within one unit of rapidity and nearby in azimuth. The data sample, which comes from {pi}{sup -}Be interactions obtained using the CERN OMEGA spectrometer, contains events with a pair of oppositely charged particles having p{sub T}{>=}2 GeV/c recoiling against a third one with p{sub T}{>=}1 GeV/c. Our data provide new information on short range correlations involving the production of the nine possible pairs made from ({pi}{sup +}, K{sup +}, p) and ({pi}{sup -}, K{sup -}, anti p). Comparison with Lund Monte Carlo predictions is made. Apart from proton yields, the model reproduces correctly our data. The main discrepancies observed with protons can be attributed to hard scattering of diquarks from the target nucleons. (orig.).

  11. Sterility Testing of Stem Cell Products by Broad-Range Bacterial 16S Ribosomal DNA Polymerase Chain Reaction.

    Science.gov (United States)

    Tokuno, Osamu; Hayakawa, Akira; Yanai, Tomoko; Mori, Takeshi; Ohnuma, Kenichiro; Tani, Ayumi; Minami, Hironobu; Sugimoto, Takeshi

    2015-01-01

    To evaluate broad-range 16S ribosomal DNA (rDNA) polymerase chain reaction (PCR) as a rapid screening tool to detect bacterial contamination of stem-cell products. We performed the evaluation using whole blood spiked with serially diluted bacterial-type strains. Detection sensitivity was defined as the bacterial concentration for which all replicates were positive at each concentration (100% detection). We tested the sterility of 29 bags of autologous peripheral blood stem cell (PBSC) products harvested at our facility using the 16S rDNA PCR method. The detection sensitivity of 16S rDNA PCR in spiked whole blood was 10¹ to 10² colony-forming units (CFU) per mL, depending on the bacterial strain. We detected no amplified 16S rDNA among the PBSCs we used in this study. The BacT/ALERT automated bacterial culture system that we used also showed no positive signals in any of the PBSCs tested. Our data indicate that bacterial 16S rDNA PCR is a useful alternative for rapid sterility testing, not only for blood products used in transfusion medicine but also for stem-cell products used in regenerative medicine. Copyright© by the American Society for Clinical Pathology (ASCP).

  12. Zn-Mo/HZSM-5 Catalyst for Gasoil Range Hydrocarbon Production by Catalytic Hydrocracking of Ceiba pentandra oil

    Directory of Open Access Journals (Sweden)

    Yustia Wulandari Mirzayanti

    2018-01-01

    Full Text Available Biofuel from vegetable oil becomes one of the most suitable and logical alternatives to replace fossil fuel. The research focused on various metal ratio Zinc/Molybdenum/HZSM-5 (Zn-Mo/HZSM-5 catalyst to produce liquid hydrocarbon via catalytic hydrocracking of Ceiba penandra oil. The catalytic hydrocracking process has been applied in this study to crack Ceiba pentandra oil into a gasoil range hydrocarbon using Zn-Mo/HZSM-5 as a catalyst. The effect of various reaction temperature on the catalytic hydrocracking of Ceiba pentandra oil were studied. The Zn-Mo/HZSM-5 catalyst with metal ratio was prepared by incipient wetness impregnation method. This process used slurry pressure batch reactor with a mechanical stirrer. A series of experiments were carried out in the temperature range from 300-400 oC for 2 h at pressure between 10-15 bar. The conversion and selectivity were estimated. The liquid hydrocarbon product were identified to gasoline, kerosene, and gas oil. The results show that the use of Zn-Mo/HZSM-5 can produce gas oil as the most component in the product. Overall, the highest conversion and selectivity of gas oil range hydrocarbon was obtained when the ZnMo/HZSM-5 metal ratio was Zn(2.86 wt.%-Mo(5.32 wt.%/HZSM-5 and the name is Zn-Mo/HZSM-5_102. The highest conversion was obtained at 63.31 % and n-paraffin (gas oil range selectivity was obtained at 90.75 % at a temperature of 400 oC. Ceiba pentandra oil can be recommended as the source of inedible vegetable oil to produce gasoil as an environmentally friendly transportation fuel. Copyright © 2018 BCREC Group. All rights reserved Received: 8th September 2017; Revised: 9th September 2017; Accepted: 17th September 2017; Available online: 22nd January 2018; Published regularly: 2nd April 2018 How to Cite: Mirzayanti, Y.W., Kurniawansyah, F., Prajitno, D.H., Roesyadi, A. (2018. Zn-Mo/HZSM-5 Catalyst for Gasoil Range Hydrocarbon Production by Catalytic Hydrocracking of Ceiba pentandra

  13. Avian foods, foraging and habitat conservation in world rice fields

    Science.gov (United States)

    Stafford, J.D.; Kaminski, R.M.; Reinecke, K.J.

    2010-01-01

    Worldwide, rice (Oryza sativa) agriculture typically involves seasonal flooding and soil tillage, which provides a variety of microhabitats and potential food for birds. Water management in rice fields creates conditions ranging from saturated mud flats to shallow (waste rice) is typically the most abundant potential food of birds in rice fields, with estimates of seed mass from North America ranging from 66672 kg/ha. Although initially abundant after harvest, waste rice availability can be temporally limited. Few abundance estimates for other foods, such as vertebrate prey or forage vegetation, exist for rice fields. Outside North America, Europe and Japan, little is known about abundance and importance of any avian food in rice fields. Currently, flooding rice fields after harvest is the best known management practice to attract and benefit birds. Studies from North America indicate specific agricultural practices (e.g. burning stubble) may increase use and improve access to food resources. Evaluating and implementing management practices that are ecologically sustainable, increase food for birds and are agronomically beneficial should be global priorities to integrate rice production and avian conservation. Finally, land area devoted to rice agriculture appears to be stable in the USA, declining in China, and largely unquantified in many regions. Monitoring trends in riceland area may provide information to guide avian conservation planning in rice-agriculture ecosystems.

  14. Tropical forage legumes for environmental benefits: An overview

    Directory of Open Access Journals (Sweden)

    Rainer Schultze-Kraft

    2018-01-01

    Full Text Available Ruminant livestock production in the tropics, particularly when based on pastures, is frequently blamed for being detrimental to the environment, allegedly contributing to: (1 degradation and destruction of ecosystems, including degradation and loss of soil, water and biodiversity; and (2 climate change (global warming. In this paper we argue that, rather than being detrimental, tropical forage legumes can have a positive impact on the environment, mainly due to key attributes that characterize the Leguminosae (Fabaceae family: (1 symbiotic nitrogen fixation; (2 high nutritive value; (3 deep-reaching tap-root system; (4 wide taxonomic and genetic diversity; and (5 presence of particular secondary metabolites. Although there are also potential negative aspects, such as soil acidification and the risks of introduced legumes becoming invasive weeds, we submit that legumes have potential to contribute significantly to sustainable intensification of livestock production in the tropics, along with the provision of ecosystem services. To further assess, document and realize this potential, research for development needs in a range of areas are indicated.

  15. Future Interagency Range and Spaceport Technologies (FIRST) Formulation Products: 1. Transformational Spaceport and Range Concept of Operations. 2. F.I.R.S.T. Business Case Analysis

    Science.gov (United States)

    2005-01-01

    The Baseline Report captures range and spaceport capabilities at five sites: KSC, CCAFS, VAFB, Wallops, and Kodiak. The Baseline depicts a future state that relies on existing technology, planned upgrades, and straight-line recapitalization at these sites projected through 2030. The report presents an inventory of current spaceport and range capabilities at these five sites. The baseline is the first part of analyzing a business case for a set of capabilities designed to transform U.S. ground and space launch operations toward a single, integrated national "system" of space transportation systems. The second part of the business case compares current capabilities with technologies needed to support the integrated national "system". The final part, a return on investment analysis, identifies the technologies that best lead to the integrated national system and reduce recurring costs..Numerous data sources were used to define and describe the baseline spaceport and range by identifying major systems and elements and describing capabilities, limitations, and capabilities

  16. Southern Elephant Seals Replenish Their Lipid Reserves at Different Rates According to Foraging Habitat.

    Directory of Open Access Journals (Sweden)

    Gaëtan Richard

    Full Text Available Assessing energy gain and expenditure in free ranging marine predators is difficult. However, such measurements are critical if we are to understand how variation in foraging efficiency, and in turn individual body condition, is impacted by environmentally driven changes in prey abundance and/or accessibility. To investigate the influence of oceanographic habitat type on foraging efficiency, ten post-breeding female southern elephant seals Mirounga leonina (SES were equipped and tracked with bio-loggers to give continuous information of prey catch attempts, body density and body activity. Variations in these indices of foraging efficiency were then compared between three different oceanographic habitats, delineated by the main frontal structures of the Southern Ocean. Results show that changes in body density are related not only to the number of previous prey catch attempts and to the body activity (at a 6 day lag, but also foraging habitat type. For example, despite a lower daily prey catch attempt rate, SESs foraging north of the sub-Antarctic front improve their body density at a higher rate than individuals foraging south of the sub-Antarctic and polar fronts, suggesting that they may forage on easier to catch and/or more energetically rich prey in this area. Our study highlights a need to understand the influence of habitat type on top predator foraging behaviour and efficiency when attempting a better comprehension of marine ecosystems.

  17. Short communication: Forage particle size and fat intake affect rumen passage, the fatty acid profile of milk, and milk fat production in dairy cows consuming dried distillers grains with solubles.

    Science.gov (United States)

    Ramirez Ramirez, H A; Harvatine, K J; Kononoff, P J

    2016-01-01

    Four ruminally cannulated Holstein cows averaging (± SD) 116 ± 18 d in milk and 686 ± 52 kg of body weight were used in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments to test the effects of forage particle size and concentration of corn oil on milk fat depression. Cows were housed in individual stalls, milked daily at 0700 and 1800 h, and individually fed daily at 0900 h for ad libitum consumption allowing approximately 10% orts. Four 28-d periods, in which each cow was offered 1 of 4 total mixed rations, included reduced-fat dried distillers grains with solubles at 30% of dietary dry matter and differed in forage particle size by inclusion of chopped grass hay (LONGP) or grass hay pellets (SHORTP) and 0 or 2% corn oil (CO). Dietary treatments were 0% corn oil + short particle size (CO0+SHORTP), 0% corn oil + long particle size (CO0+LONGP), 2% corn oil + short particle size (CO2 + SHORTP), and 2% corn oil + long particle size (CO2 + LONGP). Dry matter intake and milk yield were not affected by treatment averaging 26.5 ± 1.19 kg/d and 32.8 ± 3.34 kg/d, respectively. A decrease was found in 3.5% fat-corrected milk with the inclusion of oil resulting in 34.6 and 26.6 ± 2.6 kg/d for 0 and 2% oil diets, respectively. An oil × size interaction was found for milk fat concentration resulting in 2.27, 3.02, 3.62, and 3.62 ± 0.23% for CO2+SHORTP, CO2 + LONGP, CO0 + SHORTP, and CO0 + LONGP, respectively. Fat yield was reduced from 1.22 to 0.81 ± 0.09 kg/d with 2% oil diets. Cows consuming diets with long particle size spent 29 more minutes eating compared with the cows consuming short particle size (198 and 169 ± 15 min/d). Rumination time decreased from 504 to 400 ± 35 min/d for cows consuming short particle size compared with long particle size. Total chewing was reduced from 702 to 570 ± 4 min/d when cows consumed short particle size. Feeding long particle size decreased rate of passage of dry matter from 3.38 to 2.89 ± 0.42%/h

  18. Forragem hidropônica de milheto: produção e qualidade nutricional em diferentes densidades de semeadura e idades de colheita Hydroponic millet forage: production and naurishing quality in different sowing densities and harvest ages

    Directory of Open Access Journals (Sweden)

    Liziany Müller

    2006-08-01

    Full Text Available Com objetivo de avaliar a produtividade e a qualidade nutricional da forragem hidropônica de milheto, realizou-se um experimento no Departamento de Fitotecnia da Universidade Federal de Santa Maria (UFSM - RS, identificando a densidade adequada de sementes e a idade ideal de colheita. Adotou-se o delineamento experimental inteiramente casualizado; os tratamentos foram distribuídos em esquema fatorial 4x2, constituídos por quatro densidades de semeadura (0,5, 1,0, 1,5 e 2,0kg m-2 e duas colheitas (10 e 20 dias. Não foi observada significância à interação densidade x idade de colheita para nenhuma das variáveis analisadas. A estatura, a fitomassa seca, a hemicelulose e a lignina não foram influenciadas pela densidade de semeadura. O aumento da densidade de semeadura promoveu incremento na fitomassa fresca e no teor de proteína bruta e redução nos teores de fibra em detergente neutro e ácido e em celulose. A colheita aos 10 dias permitiu maiores valores de fitomassa fresca e seca, de hemicelulose, de celulose e menores valores de fibra em detergente neutro e ácido, e de lignina. Em relação à proteína bruta, não foi observada diferença significativa para as colheitas aos 10 e 20 dias. Pode-se sugerir o cultivo da forragem hidropônica de milheto, com densidade de semeadura de 2kg m-2, e colheita aos 10 dias, para se obter boa produção com qualidade nutricional.This study aimed to evaluate the effect of different harvest dates and sowing densities on growth and bromatological composition of hydroponic millet forage. The experiment was carried out in the Crop Production of the Universidade Federal of Santa Maria, RS, Brazil. A randomized experimental design was used. Treatments consisted of four sowing densities (0.5, 1.0, 1.5 e 2.0kg seed m-2 and two harvest dates (10 and 20 days after germination distributed in a 4x2 factorial scheme. There was no interaction between sowing densities and harvest date for all analyzed variables

  19. Geographic structure of adelie penguin populations: overlap in colony-specific foraging areas

    Science.gov (United States)

    Ainley, D.G.; Ribic, C.A.; Ballard, G.; Heath, S.; Gaffney, I.; Karl, B.J.; Barton, K.J.; Wilson, P.R.; Webb, S.

    2004-01-01

    In an investigation of the factors leading to geographic structuring among Ade??lie Penguin (Pygoscelis adeliae) populations, we studied the size and overlap of colony-specific foraging areas within an isolated cluster of colonies. The study area, in the southwestern Ross Sea, included one large and three smaller colonies, ranging in size from 3900 to 135000 nesting pairs, clustered on Ross and Beaufort Islands. We used triangulation of radio signals from transmitters attached to breeding penguins to determine foraging locations and to define colony-specific foraging areas during the chick-provisioning period of four breeding seasons, 1997-2000. Colony populations (nesting pairs) were determined using aerial photography just after egg-laying; reproductive success was estimated by comparing ground counts of chicks fledged to the number of breeding pairs apparent in aerial photos. Foraging-trip duration, meal size, and adult body mass were estimated using RFID (radio frequency identification) tags and an automated reader and weighbridge. Chick growth was assessed by weekly weighing. We related the following variables to colony size: foraging distance, area, and duration; reproductive success; chick meal size and growth rate; and seasonal variation in adult body mass. We found that penguins foraged closest to their respective colonies, particularly at the smaller colonies. However, as the season progressed, foraging distance, duration, and area increased noticeably, especially at the largest colony. The foraging areas of the smaller colonies overlapped broadly, but very little foraging area overlap existed between the large colony and the smaller colonies, even though the foraging area of the large colony was well within range of the smaller colonies. Instead, the foraging areas of the smaller colonies shifted as that of the large colony grew. Colony size was not related to chick meal size, chick growth, or parental body mass. This differed from the year previous to

  20. 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

  1. Evaluación de indicadores productivos en conejas mestizas con una dieta basada en forraje y pienso criollo Evaluation of productive indicators in crossbred does with a diet based on forage and homemade concentrate

    Directory of Open Access Journals (Sweden)

    O López

    2011-03-01

    Full Text Available Con el objetivo de evaluar el comportamiento productivo de conejas mestizas se utilizaron un total de 24 reproductoras, entre 10 y 18 meses de edad, con un peso promedio superior a los 3,0 kg durante cuatro meses. Las reproductoras consumieron una dieta constituida por: forraje de morera (Morus alba: 0,30 kg; caña (Saccharum officinarum molida: 0,25 kg, glycine (Neonotonia wightii: 0,40 kg y pienso criollo: 0,06 kg. Las crías se pesaron al nacimiento, a los 20 y a los 45 días de edad. En las reproductoras se controló las crías nacidas vivas y destetadas por parto. Se obtuvo como promedio 6,4 gazapos vivos por parto con 0,054 kg de PV al nacimiento y se destetaron 5,4 crías a los 45 días de edad con un peso de 0,694 kg. Además, se encontró un 84,4% de supervivencia durante la etapa de lactación. La ganancia media diaria durante la lactancia fue de 0,014 kg/animal/día. Los resultados evidenciaron que con la dieta propuesta se obtuvieron indicadores productivos alentadores en reproductoras mestizas.With the objective of evaluating the productive performance of crossbred does, a total of 24 animals were used, between 10 and 18 months old, with average weight higher than 3,0 kg, during four months. The does ate a diet constituted by mulberry (Morus alba forage: 0,30 kg; ground sugarcane (Saccharum officinarum: 0,25 kg; glycine (Neonotonia wightii: 0,40 kg and homemade concentrate: 0,06 kg. The young rabbits were weighed at birth, 20 and 45 days after birth. In the does the offspring born alive and weaned per parturition, were controlled. As average, 6,4 live rabbits were obtained per parturition, with 0,054 kg LW at birth and 5,4 rabbits were weaned being 45 days old and weighing 0,694 kg. In addition, 84,4% survival was found during the lactation stage. The mean daily gain during lactation was 0,014 kg/animal/day. The results proved that with the proposed diet encouraging productive indicators were obtained in crossbred does.

  2. Produção de forragem do capim-tanzânia sob intervalos de corte e doses de potássio Forage production of Tanzania grass under cutting intervals and potassium doses

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    Milena Rízzia Ferreira de Souza

    2007-10-01

    Full Text Available O experimento foi conduzido em campo, numa área estabelecida com o capim-tanzânia em novembro de 1997, em Lavras - MG, de agosto de 2001 a maio de 2002. Objetivou-se avaliar a influência de quatro intervalos de corte (4, 6, 8 e 10 semanas e três doses de K2O (0, 100 e 200 kg/ha na produção de forragem de Panicum maximum Jacq. cv. Tanzânia 1. O experimento, um fatorial 4 x 3, teve como delineamento experimental blocos ao acaso, com quatro repetições. A adubação de manutenção constituiu de N de 150 kg/ha, como sulfato de amônio, de P2O5 de 60 kg/ha, como superfosfato simples, e de K2O de 50 kg/ha, como cloreto de potássio. A adubação potássica foi aplicada a lanço, nas entrelinhas do capim-tanzânia, sendo em duas aplicações. Registrou-se incrementos lineares da altura de perfilho e da produção de MS do capim-tanzânia com o aumento dos intervalos de corte. A densidade de perfilhos e a relação folha/colmo foram independentes dos tratamentos aplicados.The experiment was carried out in a field previously seeded in November of 1997, with Tanzania grass, at Lavras-MG, Brazil from August of 2001, to May of 2002, with the objective to evaluate the influence of four cutting intervals (4, 6, 8 and 10 weeks and three K2O doses (0, 100 and 200 kg/ha on growth and forage production of Panicum maximum Jacq. cv. Tanzania 1. Soil analysis of the experimental area was made and a maintenance fertilization was done, by applying 150 kg/ha of N, as ammonium sulfate, 60 kg/ha of P2O5, as simple superphosphate, and 50 kg/ha of K2O, as potassium chloride. The treatments were combined in a factorial 4x3 design, in randomized blocks with four replications. Potassium fertilization was done in broadcast method between lines of tanzania grass, in two applications. Linear increments of tiller height and dry matter production of tanzania grass were observed by increasing the cutting intervals. The tiller density and the leaf/stem ratio were

  3. Lâminas de água e doses de nitrogênio na produção de aveia (Avena sativa L. para forragem Irrigation depths and nitrogen levels for forage oat (Avena sativa L. production

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    J. A. Frizzone

    1995-12-01

    Full Text Available Foi realizado experimento visando estudar os efeitos da irrigação suplementar e da adubação nitrogenada na produtividade de aveia (Avena sativa L., variedade UPF7, para ferragem. O delineamento experimental foi o de blocos ao acaso com parcelas subdivididas, com quatro repetições. Os tratamentos constaram da combinação de quatro lâminas de irrigação aplicadas quando a evaporação acumulada no tanque "Classe A" (ECA atingia aproximadamente 30 mm (I = 0%, I = 50%, I = 100% e I = 150% de ECA e quatro níveis de adubação nitrogenada (N = O, N = 80, N = 160 e N = 240 kg.ha-1 de nitrogênio. A máxima produtividade total de matéria seca (6,9 Lha-1 foi estimada para 319,2 mm de água e 152,4 kg.ha-1 de nitrogênio. Aos preços considerados para insumos e produto, a máxima receita líquida (R$ 897.ha-1 foi obtida para 310 mm de água e 120 kg.ha-1 de nitrogênio.This study was conducted to determine the effects of supplemental irrigation and nitrogen fertilization on forage oat (Avena sativa, L. productivity, variety UPF7. The experiment was a split-plot randomized block design with four replications. The experimental unit consisted of combinations of four irrigation depths applied when cumulative Classe A pan evaporation (ECA approximately reached 30 mm, (I = 0%, I = 50%, I = 100% and I = 150% of ECA, and four nitrogen levels (N = O, N = 80, N = 160 e N = 240 kg.ha-1. The total maximum productivity of dry matter (6,9 t.ha-1 was obtained for the water depth of 319,2 mm and 152,4 kg.ha-1 of nitrogen. For the considered prices, the water and nitrogen levels that induced the maximum net income were 310 mm and 120 kg.ha-1, respectively, reaching a maximum net return of R$ 897.ha-1.

  4. Utilization of male sterility in forage crops

    Energy Technology Data Exchange (ETDEWEB)

    Suginobu, Ken-ichi (National Grassland Research Inst., Nishinasuno, Tochigi (Japan))

    1982-03-01

    The genetic nature of male sterility in forage crops was reviewed. Many workers have suggested that hybrids in forage crops are quite promising. First, the selection of the most desirable parental genotype from a large original population is improtant in heterosis breeding programs. After the more promising inbreds or clones have been selected on the basis of good general combining ability, it is necessary to identify the particular single, three-way or double cross that will produce the highest yields. A high seed yield potential is also important in a new variety so that the seeds can be sold at lower prices than other varieties. A tentative scheme for hybrid seed production by using inbred lines of male sterile or normal parents is proposed. At a breeding station, the seeds for male sterile F/sub 1/(AB), maintainer S/sub 1/(C-S/sub 1/) and either maintainer or restorer S/sub 1/s(D-S/sub 1/, E-S/sub 1/) are produced from the parental clones. At a seed increase agency, the seeds for male sterile F/sub 1/(ABC) and either maintainer or restorer S/sub 2/(D-S/sub 2/) are produced. In the case that D-S/sub 2/ seed production is difficult, maintainer or restorer F/sub 1/(DE) should be produced from D-S/sub 1/ x E-S/sub 1/. These seeds are used for commercial seed production. Seeds of hybrid F/sub 1/(ABCD) or hybrid F/sub 1/(ABCDE) are for practical use.

  5. Legume-Cereal Intercropping Improves Forage Yield, Quality and Degradability.

    Science.gov (United States)

    Zhang, Jie; Yin, Binjie; Xie, Yuhuai; Li, Jing; Yang, Zaibin; Zhang, Guiguo

    2015-01-01

    Intercropping legume with cereal is an extensively applied planting pattern in crop cultivation. However, forage potential and the degradability of harvested mixtures from intercropping system remain unclear. To investigate the feasibility of applying an intercropping system as a forage supply source to ruminants, two consecutive experiments (experiments 1 and 2) involving a field cultivation trial and a subsequent in vivo degradable experiment were conducted to determine the forage production performance and the ruminally degradable characteristics of a harvested mixture from an alfalfa/corn-rye intercropping system. In experiment 1, the intercropping system was established by alternating alfalfa and corn or rye with a row ratio of 5:2. Dry matter (DM) and nutrient yields were determined. In experiment 2, forages harvested from the different treatments were used as feedstuff to identify nutrient degradation kinetics and distribution of components between the rapidly degradable (a), potentially degradable (b) and the degradation rate constant (c) of 'b' fraction by in sacco method in Small-Tail Han wether Sheep. The intercropping system of alfalfa and corn-rye provided higher forage production performance with net increases of 9.52% and 34.81% in DM yield, 42.13% and 16.74% in crude protein (CP) yield, 25.94% and 69.99% in degradable DM yield, and 16.96% and 5.50% in degradable CP yield than rotation and alfalfa sole cropping systems, respectively. In addition, the harvest mixture from intercropping system also had greater 'a' fraction, 'b' fraction, 'c' values, and effective degradability (E value) of DM and CP than corn or rye hay harvested from rotation system. After 48-h exposure to rumen microbes, intercropping harvest materials were degraded to a higher extent than separately degraded crop stems from the sole system as indicated by visual microscopic examination with more tissues disappeared. Thus, the intercropping of alfalfa and corn-rye exhibited a greater

  6. Information Foraging for Perceptual Decisions

    OpenAIRE

    Ludwig, Casimir J.H.; Evens, David R

    2016-01-01

    We tested an information foraging framework to characterize the mechanisms that drive active (visual) sampling behavior in decision problems that involve multiple sources of information. Experiments 1 through 3 involved participants making an absolute judgment about the direction of motion of a single random dot motion pattern. In Experiment 4, participants made a relative comparison between 2 motion patterns that could only be sampled sequentially. Our results show that: (a) Information (abo...

  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. Effect of Feed Additives on Productivity and Campylobacter spp. Loads in Broilers Reared under Free Range Conditions

    Directory of Open Access Journals (Sweden)

    Muriel Guyard-Nicodème

    2017-05-01

    Full Text Available The poultry reservoir, especially broiler meat, is generally recognized as one of the most-important sources for human Campylobacteriosis. The measures to control Campylobacter targeted essentially the primary production level. The aim of this work was to evaluate the effectiveness of different treatments against natural Campylobacter colonization in a French experimental farm of free-range broilers during the whole rearing period. Five commercial products and a combination of two of them were tested and all the products were added to feed or to water at the dose recommended by the suppliers. Campylobacter loads in caeca and on carcasses of broilers at the slaughter were determined by culture methods. Natural contamination of the flock occurred at the end of the indoor rearing period between day 35 and day 42. At day 42, the multispecies probiotic added to the feed reduced the contamination of 0.55 log10 CFU/g (p = 0.02 but was not significant (p > 0.05 at the end of rearing at day 78. However, another treatment, a combination of a cation exchange clay-based product in feed and an organic acid mixture (formic acid, sodium formate, lactic acid, propionic acid in water, led to a slight but significant reduction of 0.82 ± 0.25 log10 CFU/g (p = 0.02 compared to the control group at day 78. Testing this combination in field conditions in several flocks is needed to determine if it is biologically relevant and if it could be a valuable measure to reduce Campylobacter in broiler flocks.

  9. Geographic profiling and animal foraging.

    Science.gov (United States)

    Le Comber, Steven C; Nicholls, Barry; Rossmo, D Kim; Racey, Paul A

    2006-05-21

    Geographic profiling was originally developed as a statistical tool for use in criminal cases, particularly those involving serial killers and rapists. It is designed to help police forces prioritize lists of suspects by using the location of crime scenes to identify the areas in which the criminal is most likely to live. Two important concepts are the buffer zone (criminals are less likely to commit crimes in the immediate vicinity of their home) and distance decay (criminals commit fewer crimes as the distance from their home increases). In this study, we show how the techniques of geographic profiling may be applied to animal data, using as an example foraging patterns in two sympatric colonies of pipistrelle bats, Pipistrellus pipistrellus and P. pygmaeus, in the northeast of Scotland. We show that if model variables are fitted to known roost locations, these variables may be used as numerical descriptors of foraging patterns. We go on to show that these variables can be used to differentiate patterns of foraging in these two species.

  10. Foraging patterns in online searches

    Science.gov (United States)

    Wang, Xiangwen; Pleimling, Michel

    2017-03-01

    Nowadays online searches are undeniably the most common form of information gathering, as witnessed by billions of clicks generated each day on search engines. In this work we describe online searches as foraging processes that take place on the semi-infinite line. Using a variety of quantities like probability distributions and complementary cumulative distribution functions of step length and waiting time as well as mean square displacements and entropies, we analyze three different click-through logs that contain the detailed information of millions of queries submitted to search engines. Notable differences between the different logs reveal an increased efficiency of the search engines. In the language of foraging, the newer logs indicate that online searches overwhelmingly yield local searches (i.e., on one page of links provided by the search engines), whereas for the older logs the foraging processes are a combination of local searches and relocation phases that are power law distributed. Our investigation of click logs of search engines therefore highlights the presence of intermittent search processes (where phases of local explorations are separated by power law distributed relocation jumps) in online searches. It follows that good search engines enable the users to find the information they are looking for through a local exploration of a single page with search results, whereas for poor search engine users are often forced to do a broader exploration of different pages.

  11. Compositions of seed, forage, and processed fractions from insect-protected soybean MON 87701 are equivalent to those of conventional soybean.

    Science.gov (United States)

    Berman, Kristina H; Harrigan, George G; Riordan, Susan G; Nemeth, Margaret A; Hanson, Christy; Smith, Michelle; Sorbet, Roy; Zhu, Eddie; Ridley, William P

    2009-12-09

    Monsanto Co. has developed biotechnology-derived, insect-protected soybean MON 87701 that produces the Cry1Ac insecticidal crystal (delta-endotoxin) protein derived from Bacillus thuringiensis (Bt) subsp. kurstaki. Cry1Ac provides protection from feeding damage caused by certain targeted lepidopteran pests. The purpose of this work was to assess whether the compositions of seed, forage, and processed fractions (meal, oil, protein isolate, and lecithin) of MON 87701 are comparable to those of conventional soybean. Compositional analyses were conducted on seed and forage tissues harvested from MON 87701 and conventional soybean grown in multiple replicated sites in the United States during the 2007 growing season and in Argentina during the 2007-2008 growing season. Seed, forage, and processed fractions from conventional soybean varieties currently in the marketplace were included in the analyses to establish a range of natural variability for each compositional component; the range of variability was defined by a 99% tolerance interval. Additional seed was collected from soybean grown in a separate U.S. production during the 2007 season. This seed and processed fractions (meal, oil, protein isolate, and crude lecithin) derived from it were also subjected to compositional analyses. Forage samples were analyzed for levels of proximates (ash, fat, moisture, and protein), carbohydrates by calculation, and fiber. Seed samples were analyzed for proximates, carbohydrates by calculation, fiber, amino acids, fatty acids, antinutrients, and vitamin E. Toasted, defatted (TD) meal was analyzed for proximates, fiber, amino acids, and antinutrients. Refined, bleached, and deodorized (RBD) oil was analyzed for fatty acids and vitamin E. Protein isolate was analyzed for amino acids and moisture. Crude lecithin was analyzed for phosphatides. Overall, results demonstrated that the seed, forage, and processed fractions of MON 87701 are compositionally equivalent to those of

  12. Soil microbial communities and elk foraging intensity: implications for soil biogeochemical cycling in the sagebrush steppe.

    Science.gov (United States)

    Cline, Lauren C; Zak, Donald R; Upchurch, Rima A; Freedman, Zachary B; Peschel, Anna R

    2017-02-01

    Foraging intensity of large herbivores may exert an indirect top-down ecological force on soil microbial communities via changes in plant litter inputs. We investigated the responses of the soil microbial community to elk (Cervus elaphus) winter range occupancy across a long-term foraging exclusion experiment in the sagebrush steppe of the North American Rocky Mountains, combining phylogenetic analysis of fungi and bacteria with shotgun metagenomics and extracellular enzyme assays. Winter foraging intensity was associated with reduced bacterial richness and increasingly distinct bacterial communities. Although fungal communities did not respond linearly to foraging intensity, a greater β-diversity response to winter foraging exclusion was observed. Furthermore, winter foraging exclusion increased soil cellulolytic and hemicellulolytic enzyme potential and higher foraging intensity reduced chitinolytic gene abundance. Thus, future changes in winter range occupancy may shape biogeochemical processes via shifts in microbial communities and subsequent changes to their physiological capacities to cycle soil C and N. © 2017 John Wiley & Sons Ltd/CNRS.

  13. IN VITRO NUTRITIONAL EVALUATION OF SMALL-GRAIN CEREAL FORAGE FOR SMALL-SCALE DAIRY SYSTEMS

    Directory of Open Access Journals (Sweden)

    Felipe López González

    2017-12-01

    Full Text Available Small-grain cereals are promoted as forage alternatives that may substitute for other traditional crops when short cycle forages are required for cattle feeding. The objective of the work was to assess in vitro the nutritive quality, ruminal fermentation kinetics and digestibility by the gas production technique of forage from common oat (Avena sativa cv. Canadiense = AC, black oat (Avena strigosa cv. Saia = AN, Triticale (×Triticosecale Wittm. cv. Criollo = T, and rye (Secale cereale of national production = C. The forage crops were sown in 250 m2 plots, harvested and sampled 72 days after sowing in a completely randomised design with five replicates. Both oat species (AC and AN had significantly higher crude protein and neutral detergent fibre contents (P0.05 for the evaluated forages. There were also no differences in the estimated ME content (P>0.05. Results indicate that black and common oats are forages with a better nutritive quality when harvested at a similar time compared to triticale and rye forage.

  14. Evaluation of turnip forage residue extracted from biodiesel production as supplement for grazing beef cattle Avaliação do resíduo de nabo forrageiro extraído da produção de biodiesel como suplemento para bovinos de corte em pastagens

    Directory of Open Access Journals (Sweden)

    Ana Vera Martins Franco

    2008-04-01

    Full Text Available Two experiments were performed to evaluate the use of the turnip forage residue extracted from biodiesel production as alternative protein source for grazing zebu cattle. At the first experiment, the performance of Nellore zebu cattle was evaluated on grazing grass. Twenty four animals were distributed in three treatments and allocated on six paddocks, with four animals each and two repetitions. Treatments consisted of supplements with two levels of turnip forage residue (7.5 and 15.0% dry matter and without turnip forage (control. Pasture availability and quality were also evaluated. At the second trial, degradability of the residue turnip forage was measured in six rumen fistulated zebu cattle fed basal diet composed by grass coast-cross hay and concentrate (35% CP with 15% of turnip forage. No difference was observed among the treatments for the animal performance, but the steers fed 7.5% of turnip forage residue showed the highest daily gain weight (0.575 kg DGW. The turnip forage residue showed high and fast ruminal effective degradability of the dry matter (83.8%, crude protein (88.9% and neutral detergent fiber (52.1%. In conclusion, the turnip forage residue can be used as protein source in supplement diet for cattle, shifting the conventional protein sources up to 15% in supplement with 35% of total crude protein.Dois experimentos foram realizados visando avaliar o uso do resíduo de nabo forrageiro extraído da produção de biodiesel como fonte de proteína alternativa de suplementos para bovinos de corte em pastejo de gramíneas. No primeiro experimento, avaliou-se o desempenho de bovinos Nelore a pasto (ganho diário de peso, utilizando-se 24 animais, distribuídos em três tratamentos em seis piquetes com quatro animais cada e duas repetições. Os tratamentos consistiram de suplementos com dois níveis do resíduo de nabo forrageiro (7,5 e 15,0% na matéria seca e sem nabo forrageiro (testemunha. A disponibilidade e qualidade da

  15. Group foraging in Socotra cormorants: A biologging approach to the study of a complex behavior.

    Science.gov (United States)

    Cook, Timothée R; Gubiani, Rob; Ryan, Peter G; Muzaffar, Sabir B

    2017-04-01

    Group foraging contradicts classic ecological theory because intraspecific competition normally increases with aggregation. Hence, there should be evolutionary benefits to group foraging. The study of group foraging in the field remains challenging however, because of the large number of individuals involved and the remoteness of the interactions to the observer. Biologging represents a cost-effective solution to these methodological issues. By deploying GPS and temperature-depth loggers on individuals over a period of several consecutive days, we investigated intraspecific foraging interactions in the Socotra cormorant Phalacrocorax nigrogularis , a threatened colonial seabird endemic to the Arabian Peninsula. In particular, we examined how closely birds from the same colony associated with each other spatially when they were at sea at the same time and the distance between foraging dives at different periods of the day. Results show that the position of different birds overlapped substantially, all birds targeting the same general foraging grounds throughout the day, likely following the same school of fish. There were as many as 44,500 birds within the foraging flock at sea at any time (50% of the colony), and flocking density was high, with distance between birds ranging from 8 to 1,380 m. Birds adopted a diving strategy maximizing time spent underwater relative to surface time, resulting in up to 72% of birds underwater in potential contact with prey at all times while foraging. Our data suggest that the benefits of group foraging outweigh the costs of intense aggregation in this seabird. Prey detection and information transmission are facilitated in large groups. Once discovered, shoaling prey are concentrated under the effect of the multitude. Fish school cohesiveness is then disorganized by continuous attacks of diving birds to facilitate prey capture. Decreasing population size could pose a risk to the persistence of threatened seabirds where group size

  16. Season and landscape composition affect pollen foraging distances and habitat use of honey bees.

    Science.gov (United States)

    Danner, Nadja; Molitor, Anna Maria; Schiele, Susanne; Härtel, Stephan; Steffan-Dewenter, Ingolf

    2016-09-01

    Honey bees (Apis mellifera L.) show a large variation in foraging distances and use a broad range of plant species as pollen resources, even in regions with intensive agriculture. However, it is unknown how increasing areas of mass-flowering crops like oilseed rape (Brassica napus; OSR) or a decrease of seminatural habitats (SNH) change the temporal and spatial availability of pollen resources for honey bee colonies, and thus foraging distances and frequency in different habitat types. We studied pollen foraging of honey bee colonies in 16 agricultural landscapes with independent gradients of OSR and SNH area within 2 km and used waggle dances and digital geographic maps with major land cover types to reveal the distance and visited habitat type on a landscape level. Mean pollen foraging distance of 1347 decoded bee dances was 1015 m (± 26 m; SEM). In spring, increasing area of flowering OSR within 2 km reduced mean pollen foraging distances from 1324 m to only 435 m. In summer, increasing cover of SNH areas close to the colonies (within 200 m radius) reduced mean pollen foraging distances from 846 to 469 m. Frequency of pollen foragers per habitat type, measured as the number of dances per hour and hectare, was equally high for SNH, grassland, and OSR fields, but lower for other crops and forests. In landscapes with a small proportion of SNH a significantly higher density of pollen foragers on SNH was observed, indicating that pollen resources in such simple agricultural landscapes are more limited. Overall, we conclude that SNH and mass-flowering crops can reduce foraging distances of honey bee colonies at different scales and seasons with possible benefits for the performance of honey bee colonies. Further, mixed agricultural landscapes with a high proportion of SNH reduce foraging densities of honey bees in SNH and thus possible competition for pollen resources. © 2016 by the Ecological Society of America.

  17. Product/Process (P/P) Models For The Defense Waste Processing Facility (DWPF): Model Ranges And Validation Ranges For Future Processing

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, C. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Edwards, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2015-09-25

    Radioactive high level waste (HLW) at the Savannah River Site (SRS) has successfully been vitrified into borosilicate glass in the Defense Waste Processing Facility (DWPF) since 1996. Vitrification requires stringent product/process (P/P) constraints since the glass cannot be reworked once it is poured into ten foot tall by two foot diameter canisters. A unique “feed forward” statistical process control (SPC) was developed for this control rather than statistical quality control (SQC). In SPC, the feed composition to the DWPF melter is controlled prior to vitrification. In SQC, the glass product would be sampled after it is vitrified. Individual glass property-composition models form the basis for the “feed forward” SPC. The models transform constraints on the melt and glass properties into constraints on the feed composition going to the melter in order to guarantee, at the 95% confidence level, that the feed will be processable and that the durability of the resulting waste form will be acceptable to a geologic repository.

  18. 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

  19. Efecto del forraje de Morus alba en los indicadores productivos y de salud de bovinos jóvenes en pastoreo Effect of Morus alba forage on the productive and health indicators of grazing calves

    Directory of Open Access Journals (Sweden)

    Mildrey Soca

    2010-12-01

    Full Text Available Con el objetivo de evaluar las potencialidades de la morera (Morus alba var. Cubana para la suplementación de bovinos jóvenes en pastoreo y sus efectos en la productividad y la salud de los animales, se desarrolló esta investigación en la EEPF "Indio Hatuey" durante la época lluviosa, con dos tratamientos: el grupo experimental recibía 6 kg de morera fresca troceada y 500 g de concentrado/animal/día (A; mientras que en el grupo control la suplementación era de 1 kg de concentrado/animal/día y heno de pangola a voluntad (B. Se evalúo la composición bromatológica y fitoquímica de la morera, el peso vivo, la ganancia media diaria (GMD y el conteo fecal de huevos (CFH de nemátodos gastrointestinales en los animales. Se observaron diferencias significativas (PIn order to evaluate the potential of mulberry (Morus alba var. Cubana for the supplementation of young grazing cattle and its effects on the productivity and health of the animals, this study was conducted at the EEPF "Indio Hatuey" during the rainy season, with two treatments: the experimental group received 6 kg of fresh chopped mulberry and 500 g of concentrate/animal/day (A; while in the control group supplementation was 1 kg of concentrate/animal/day and pangola grass hay ad libitum (B. The bromatological and phytochemical composition of mulberry, live weight, mean daily gain (MDG and fecal egg count (FEC of gastrointestinal nematodes in the animals were evaluated. Significant differences (P<0,001 were observed in the live weight between treatments (186,06 vs 169,01 kg. Likewise, a significant effect (P<0,05 of the MDG was detected, with values higher than 600 g in the supplemented animals. On the other hand, the FEC showed significant differences (P<0,01 since the second month of evaluation, with stable performance and values lower than 100 epg in the experimental group. Seven groups of secondary metabolites were found; the most representative ones were phenols, tripertene

  20. Effect of diatomaceous earth on parasite load, egg production, and egg quality of free-range organic laying hens.

    Science.gov (United States)

    Bennett, D C; Yee, A; Rhee, Y-J; Cheng, K M

    2011-07-01

    The effectiveness of diatomaceous earth (DE) as a treatment against parasites and to increase feed efficiency and egg production of organically raised free-range layer hens was evaluated in 2 breeds of commercial egg layers [Bovan Brown (BB) and Lowmann Brown (LB)] that differ in their resistance to internal parasitic infections. Half the hens of each breed were fed diets supplemented with DE (2%). Their internal parasite loads were assessed by biweekly fecal egg counts (FEC) and by postmortem examination of the gastrointestinal tract. Supplementing DE in diets of LB hens, the more parasite-resistant breed, did not significantly affect their FEC and adult parasite load. However, BB hens treated with dietary DE had significantly lower Capillaria FEC, slightly lower Eimeria FEC, fewer birds infected with Heterakis, and significantly lower Heterakis worm burden than control BB hens. Both BB and LB hens fed the diet containing DE were significantly heavier, laid more eggs, and consumed more feed than hens fed the control diet, but feed efficiency did not differ between the 2 dietary treatments. Additionally, BB hens consuming the DE diet laid larger eggs containing more albumen and yolk than hens consuming the control diet. In a subsequent experiment, the effectiveness of DE to treat a Northern fowl mite (Ornithonyssus sylviarum) infestation was tested. Relative to controls, both breeds of hens that were dusted with DE had reduced number of mites. The results of this study indicate the DE has the potential to be an effective treatment to help control parasites and improve production of organically raised, free-range layer hens.

  1. Changes in forage lichen biomass after insect outbreaks and fuel reduction treatment in the Blue Mountains, Oregon

    Science.gov (United States)

    Bruce McCune; Sarah Jovan; Amanda. Hardman

    2008-01-01

    Forage lichens are pendulous, hairlike species eaten by a wide range of mammals. Our overall goal was to estimate losses of Bryoria, a genus of ecologically important forage species, in forests subjected to disease and fuel reduction treatments at Starkey Experimental Forest in the Blue Mountains of northeastern Oregon. Specific objectives were to...

  2. Optimal foraging, not biogenetic law, predicts spider orb web allometry

    Science.gov (United States)

    Gregorič, Matjaž; Kiesbüy, Heine C.; Quiñones Lebrón, Shakira G.; Rozman, Alenka; Agnarsson, Ingi; Kuntner, Matjaž

    2013-03-01

    The biogenetic law posits that the ontogeny of an organism recapitulates the pattern of evolutionary changes. Morphological evidence has offered some support for, but also considerable evidence against, the hypothesis. However, biogenetic law in behavior remains underexplored. As physical manifestation of behavior, spider webs offer an interesting model for the study of ontogenetic behavioral changes. In orb-weaving spiders, web symmetry often gets distorted through ontogeny, and these changes have been interpreted to reflect the biogenetic law. Here, we test the biogenetic law hypothesis against the alternative, the optimal foraging hypothesis, by studying the allometry in Leucauge venusta orb webs. These webs range in inclination from vertical through tilted to horizontal; biogenetic law predicts that allometry relates to ontogenetic stage, whereas optimal foraging predicts that allometry relates to gravity. Specifically, pronounced asymmetry should only be seen in vertical webs under optimal foraging theory. We show that, through ontogeny, vertical webs in L. venusta become more asymmetrical in contrast to tilted and horizontal webs. Biogenetic law thus cannot explain L. venusta web allometry, but our results instead support optimization of foraging area in response to spider size.

  3. Horse owners to learn about forage and grazing management during 2008 forage conference

    OpenAIRE

    Greiner, Lori A.

    2007-01-01

    Virginia Cooperative Extension and the Virginia Forage and Grassland Council will explore how horse owners can maintain a healthy animal, pasture, and environment at this year's equine forage conference, Feb. 11-13.

  4. Persistence of forage fish ‘hot spots’ and its association with foraging Steller sea lions (Eumetopias jubatus) in southeast Alaska

    Science.gov (United States)

    Gende, Scott M.; Sigler, Michael F.

    2006-02-01

    Whereas primary and secondary productivity at oceanic 'hotspots' may be a function of upwelling and temperature fronts, the aggregation of higher-order vertebrates is a function of their ability to search for and locate these areas. Thus, understanding how predators aggregate at these productive foraging areas is germane to the study of oceanic hot spots. We examined the spatial distribution of forage fish in southeast Alaska for three years to better understand Steller sea lion ( Eumetopias jubatus) aggregations and foraging behavior. Energy densities (millions KJ/km 2) of forage fish were orders of magnitude greater during the winter months (November-February), due to the presence of schools of overwintering Pacific herring ( Clupea pallasi). Within the winter months, herring consistently aggregated at a few areas, and these areas persisted throughout the season and among years. Thus, our study area was characterized by seasonally variable, highly abundant but highly patchily distributed forage fish hot spots. More importantly, the persistence of these forage fish hot spots was an important characteristic in determining whether foraging sea lions utilized them. Over 40% of the variation in the distribution of sea lions on our surveys was explained by the persistence of forage fish hot spots. Using a simple spatial model, we demonstrate that when the density of these hot spots is low, effort necessary to locate these spots is minimized when those spots persist through time. In contrast, under similar prey densities but lower persistence, effort increases dramatically. Thus an important characteristic of pelagic hot spots is their persistence, allowing predators to predict their locations and concentrate search efforts accordingly.

  5. Research Note Testing for a decline in secondary productivity under ...

    African Journals Online (AJOL)

    We suggest that this counterintuitive result reflects the combing out, and therefore loss, of hair in the densely vegetated site. This study failed to demonstrate a decline in secondary productivity in desertified thicket and highlights the importance of replicating such studies in space and time. African Journal of Range & Forage ...

  6. Flexible foraging tactics by a large opportunistic seabird preying on forage- and large pelagic fishes

    OpenAIRE

    Montevecchi, W. A.; Benvenuti, S.; Garthe, Stefan; Davoren, G. K.; Fifield, D.

    2009-01-01

    Generalist and opportunistic marine predators use flexible foraging behaviour to exploit prey bases that change in diversity and spatial and temporal distributions, Behavioural flexibility is constrained by characteristics Such as individual cognitive and physical capabilities, age, reproductive condition and central place foraging. To assess flexibility in the foraging tactics of a marine bird, we investigated the diets and foraging behaviour of the largest seabird predator in the North Atla...

  7. THE INFLUENCE OF PRECIPITATION ON FORAGE PEA SEED YIELDS

    Directory of Open Access Journals (Sweden)

    Svetislav Popović

    2015-12-01

    Full Text Available Field pea (Pisum arvense L., also known as Austrian winter pea, is increasingly being planted in Croatia and its surrounding to produce high-quality roughage. The main characteristics of the variety are short vegetation, high forage yields and excellent forage quality that is reflected in the high protein production. Seed production of peas is a very complex process. In agricultural production the yield is under the influence of plant genetic potential and environmental factors, especially of the precipitation amount during the growing season. Seed production of forage pea variety 'Osječki zeleni' along with the climatic conditions for a nine-year period (2004-2012 were analysed. The analyses showed large variability in yields, germination and 1000 grain weight as well as oscillations in the amounts of precipitation during the growing period of winter peas in the analysed years. Pearson's correlation coefficient analysis showed a lack of relation between yield, germination and 1000 grain weight. There was no correlation observed between the tested parameters and the total amount of precipitation during the growing period. Thus it can be concluded that the observed parameters were substantially influenced by other environmental factors.

  8. Developing Cyber Foraging Applications for Portable Devices

    DEFF Research Database (Denmark)

    Kristensen, Mads Darø; Bouvin, Niels Olof

    2008-01-01

    This paper presents the Locusts cyber foraging framework. Cyber foraging is the opportunistic use of computing resources available in the nearby environment, and using such resources thus fall into the category of distributed computing. Furthermore, for the resources to be used efficiently......, parallel computing techniques must also be employed. Distributed and parallel computing are two concepts that are both notoriously known for being very hard for developers to grasp. Because of this one might think that techniques such as cyber foraging would have a hard time surviving outside of research...... environments. In this paper a framework is presented that has special focus on making cyber foraging accessible for all developers....

  9. Social foraging with partial (public) information.

    Science.gov (United States)

    Mann, Ofri; Kiflawi, Moshe

    2014-10-21

    Group foragers can utilize public information to better estimate patch quality and arrive at more efficient patch-departure rules. However, acquiring such information may come at a cost; e.g. reduced search efficiency. We present a Bayesian group-foraging model in which social foragers do not require full awareness of their companions' foraging success; only of their number. In our model, patch departure is based on direct estimates of the number of remaining items. This is achieved by considering all likely combinations of initial patch-quality and group foraging-success; given the individual forager's experience within the patch. Slower rates of information-acquisition by our 'partially-aware' foragers lead them to over-utilize poor patches; more than fully-aware foragers. However, our model suggests that the ensuing loss in long-term intake-rates can be matched by a relatively low cost to the acquisition of full public information. In other words, we suggest that group-size offers sufficient information for optimal patch utilization by social foragers. We suggest, also, that our model is applicable to other situations where resources undergo 'background depletion', which is coincident but independent of the consumer's own utilization. Copyright © 2014 Elsevier Ltd. All rights reserved.

  10. 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,...

  11. 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,...

  12. Guanaco’s diet and forage preferences in Nothofagus forest environments of Tierra del Fuego, Argentina

    Energy Technology Data Exchange (ETDEWEB)

    Quinteros, C.P.; Bava, J.; Gobbi, M.E.; Defossé, G.E.

    2017-11-01

    Aim of study: Guanaco (Lama guanicoe Müller), is a South American native ungulate widely distributed in Patagonia, which in the island of Tierra del Fuego (TF), extends its habitat into Nothofagus spp. forests. Within these forests, guanacos consume lenga (Nothofagus pumilio) leaves and twigs, and other understory species. The aim of this work was to determine: 1) the spring and summer diet of free ranging guanacos, and 2) which plants, grown in the forest understory, guanacos do prefer, or avoid, in these seasons of great forage abundance. Area of study: Tierra del Fuego (Argentina), on three representative areas which combined Nothofagus forests and adjacent meadows (vegas). Material and Methods: uanacos’ diet was determined by comparing epidermal and non-epidermal plant fragments with micro-histological analyses of feces. The analysis was made from composite samples of fresh feces, collected at the seasons of maximum forage productivity (spring and summer). Main results: During spring, 48% of guanacos’ diet was composed of lenga leaves, 30% of grass-like species, 15% of grasses, and less than 7% of herbs, shrubs, and lichens. In summer, 40% of the diet was composed of grasses, 30% of lenga leaves, 25% of grass-like species and the rest corresponded to herbs, shrubs, and lichens. Within the forest understory, guanaco selected lenga leaves and twigs, grass species were consumed according to their availability (or sometimes rejected), while other herbs were not consumed at all. Research highlights: Guanacos’ consumption preference for lenga, even considering the high availability of other forages, could adversely affect forest regeneration.

  13. A framework for testing assumptions about foraging scales, body mass, and niche separation using telemetry data.

    Science.gov (United States)

    Cumming, Graeme S; Henry, Dominic A W; Reynolds, Chevonne

    2017-07-01

    Ecological theory predicts that if animals with very similar dietary requirements inhabit the same landscape, then they should avoid niche overlap by either exploiting food resources at different times or foraging at different spatial scales. Similarly, it is often assumed that animals that fall in different body mass modes and share the same body plan will use landscapes at different spatial scales. We developed a new methodological framework for understanding the scaling of foraging (i.e. the range and distribution of scales at which animals use their landscapes) by applying a combination of three well-established methods to satellite telemetry data to quantify foraging patch size distributions: (1) first-passage time analysis; (2) a movement-based kernel density estimator; and (3) statistical comparison of resulting histograms and tests for multimodality. We demonstrate our approach using two sympatric, ecologically similar species of African ducks with quite different body masses: Egyptian Geese (actually a shelduck), and Red-billed Teal. Contrary to theoretical predictions, the two species, which are sympatric throughout the year, foraged at almost identical spatial scales. Our results show how ecologists can use GPS tracking data to explicitly quantify and compare the scales of foraging by different organisms within an animal community. Our analysis demonstrates both a novel approach to foraging data analysis and the need for caution when making assumptions about the relationships among niche separation, diet, and foraging scale.

  14. Evidence of Lévy walk foraging patterns in human hunter–gatherers

    Science.gov (United States)

    Raichlen, David A.; Wood, Brian M.; Gordon, Adam D.; Mabulla, Audax Z. P.; Marlowe, Frank W.; Pontzer, Herman

    2014-01-01

    When searching for food, many organisms adopt a superdiffusive, scale-free movement pattern called a Lévy walk, which is considered optimal when foraging for heterogeneously located resources with little prior knowledge of distribution patterns [Viswanathan GM, da Luz MGE, Raposo EP, Stanley HE (2011) The Physics of Foraging: An Introduction to Random Searches and Biological Encounters]. Although memory of food locations and higher cognition may limit the benefits of random walk strategies, no studies to date have fully explored search patterns in human foraging. Here, we show that human hunter–gatherers, the Hadza of northern Tanzania, perform Lévy walks in nearly one-half of all foraging bouts. Lévy walks occur when searching for a wide variety of foods from animal prey to underground tubers, suggesting that, even in the most cognitively complex forager on Earth, such patterns are essential to understanding elementary foraging mechanisms. This movement pattern may be fundamental to how humans experience and interact with the world across a wide range of ecological contexts, and it may be adaptive to food distribution patterns on the landscape, which previous studies suggested for organisms with more limited cognition. Additionally, Lévy walks may have become common early in our genus when hunting and gathering arose as a major foraging strategy, playing an important role in the evolution of human mobility. PMID:24367098

  15. Evidence of Levy walk foraging patterns in human hunter-gatherers.

    Science.gov (United States)

    Raichlen, David A; Wood, Brian M; Gordon, Adam D; Mabulla, Audax Z P; Marlowe, Frank W; Pontzer, Herman

    2014-01-14

    When searching for food, many organisms adopt a superdiffusive, scale-free movement pattern called a Lévy walk, which is considered optimal when foraging for heterogeneously located resources with little prior knowledge of distribution patterns [Viswanathan GM, da Luz MGE, Raposo EP, Stanley HE (2011) The Physics of Foraging: An Introduction to Random Searches and Biological Encounters]. Although memory of food locations and higher cognition may limit the benefits of random walk strategies, no studies to date have fully explored search patterns in human foraging. Here, we show that human hunter-gatherers, the Hadza of northern Tanzania, perform Lévy walks in nearly one-half of all foraging bouts. Lévy walks occur when searching for a wide variety of foods from animal prey to underground tubers, suggesting that, even in the most cognitively complex forager on Earth, such patterns are essential to understanding elementary foraging mechanisms. This movement pattern may be fundamental to how humans experience and interact with the world across a wide range of ecological contexts, and it may be adaptive to food distribution patterns on the landscape, which previous studies suggested for organisms with more limited cognition. Additionally, Lévy walks may have become common early in our genus when hunting and gathering arose as a major foraging strategy, playing an important role in the evolution of human mobility.

  16. Individual specialization in the foraging habits of female bottlenose dolphins living in a trophically diverse and habitat rich estuary

    Science.gov (United States)

    Rossman, Sam; Ostrom, Peggy H.; Stolen, Megan; Barros, Nélio B.; Gandhi, Hasand; Stricker, Craig A.; Wells, Randall S.

    2015-01-01

    We examine individual specialization in foraging habits (foraging habitat and trophic level) of female bottlenose dolphins (Tursiops truncatus) resident in Sarasota Bay, Florida, USA, by analyzing time series of stable isotope (δ15N and δ13C) values in sequential growth layer groups within teeth. The isotope data provide a chronology of foraging habits over the lifetime of the individual and allowed us to show that female bottlenose dolphins exhibit a high degree of individual specialization in both foraging habitat and trophic level. The foraging habits used by adult females are similar to those they used as calves and may be passed down from mother to calf through social learning. We also characterized the foraging habits and home range of each individual by constructing standard ellipses from isotope values and dolphin sightings data (latitude and longitude), respectively. These data show that Sarasota Bay bottlenose dolphins forage within a subset of the habitats in which they are observed. Moreover, females with similar observational standard ellipses often possessed different foraging specializations. Female bottlenose dolphins may demonstrate individual specialization in foraging habits because it reduces some of the cost of living in groups, such as competition for prey.

  17. Costs associated with tail autotomy in an ambush foraging lizard ...

    African Journals Online (AJOL)

    . Most studies on the effects of tail loss have focused on active foraging lizards, but few data exist for ambush foraging lizards. We investigated potential costs associated with tail autotomy in an extreme ambush foraging cordylid lizard, ...

  18. Foraging behaviour of the Tawny-flanked Prinia Prinia subflava ...

    African Journals Online (AJOL)

    ) was studied at Morogoro, eastern Tanzania during the late winter, 2016. TFP foraged mostly in dense subcanopy or weedy vegetation. They foraged alone or in loosely constructed groups, and stayed in contact using calling. Foraging ...

  19. Interactions between shoal size and conformity in guppy social foraging

    NARCIS (Netherlands)

    Day, R.L.; Macdonald, T.; Brown, C.; Laland, K.N.; Reader, S.M.

    2001-01-01

    Previous experimental studies have established that shoaling fish forage more effectively in large than small groups. We investigated how shoal size affects the foraging efficiency of laboratory populations of the guppy, Poecilia reticulata, exposed to different foraging tasks. Experiment 1

  20. Produção e avaliação bromatológica de espécies forrageiras irrigadas com água salina Production and bromatological evaluation of forage species irrigated with saline water

    Directory of Open Access Journals (Sweden)

    Sebastião B. de Carvalho Júnior

    2010-10-01

    Full Text Available Uma das alternativas para a destinação de rejeito de dessalinizadores é a utilização em tanques de piscicultura e carcinocultura e posterior reúso na irrigação de culturas tolerantes a salinidade. O trabalho foi conduzido no município de Barra de Santa Rosa, PB, objetivando verificar a taxa de germinação da semente, brotação das mudas e características bromatológicas de maniçoba (Manihot glaziovii Muell Arg, erva-sal (Atriplex nummularia, flor de seda (Calotropis procera e jureminha (Desmanthus virgatus, cultivadas e irrigadas com água excedentes de tanques de piscicultura e carcinocultura, oriundos de rejeito de dessalinizadores, com condutividade elétrica de 5.800 e 5.200 μS cm-1, respectivamente. A flor de seda e erva-sal apresentam maiores taxas de germinação (96,0% e brotação (70,0%, respectivamente, seguidas da taxa de brotação da maniçoba (62,0% e da jureminha (51,0%. Do total de mudas transplantadas 95,0; 93,0; 82,7 e 80,5% das plantas de flor de seda, maniçoba, atriplex e jureminha, foram viáveis, respectivamente. As forrageiras apresentaram boa taxa de brotação e germinação e propagação e boa composição bromotologica, onde a jureminha e o atriplex apresentaram teor de proteína, matéria orgânica e energia bruta de 9,4 e 17,8%; 95,0 e 76,3% e 4.295,8 e 3.575,9 cal g-1 de energia bruta, respectivamente.One of the alternatives for the disposal of desalinization waste is its use in fishponds and shrimp production and later reuse for irrigation of crops tolerant to salinity. This work was conducted in Barra de Santa Rosa, PB, with the aim of verifying the rate of seed germination, sprouting and bromatologic characteristics of maniçoba (Manihot glaziovii Muell Arg, erva-sal (Atriplex nummularia, silk flower (Calotropis procera and 'jureminha' (Desmanthus virgatus, cultivated and irrigated with excess water of fishponds and shrimp production, coming from desalinization waste, with electrical conductivity