Riber, Anja B.; Guzman, Diego A.
Simple Summary Chicks require heat to maintain body temperature during the first weeks after hatch. Heat is normally provided by use of heating lamps or whole-house heating, but an alternative is dark brooders, i.e. horizontal heating elements equipped with curtains. The effects of providing layer chicks with dark brooders during the brooding period on behavior and fearfulness were investigated. Brooders resulted in chicks showing less locomotive activity, feather pecking and fleeing. Also, a long-term reduction of fearfulness in brooder birds was found. Results support the suggestion that rearing with dark brooders can be a successful method of reducing or preventing some of the major welfare problems in layers. Abstract Chicks require heat to maintain body temperature during the first weeks after hatch. This may be provided by dark brooders; i.e., horizontal heating elements equipped with curtains. The objective was to test effects of rearing layer chicks with dark brooders on time budget and fearfulness. Behavioral observations were performed during the first six weeks of age. Three different fear tests were conducted when the birds were age 3–6, 14–15 and 26–28 weeks. During the first four days, brooder chicks rested more than control chicks whereas they spent less time drinking, feather pecking and on locomotion (p ≤ 0.009). On days 16, 23, 30 and 42, brooder chicks spent less time on feather pecking, locomotion and fleeing (p ≤ 0.01) whereas foraging and dust bathing occurred more often on day 42 (p ≤ 0.032). Brooder birds had shorter durations of tonic immobility at all ages (p = 0.0032), moved closer to the novel object at age 15 weeks (p < 0.0001), and had shorter latencies to initiate locomotion in the open-field test at age 28 weeks (p < 0.0001). Results support the suggestion that dark brooders can be a successful method of reducing or preventing fear and feather pecking in layers. PMID:26751482
Riber, Anja Brinch; Guzman, Diego A.
to the novel object at age 15 weeks (p open-field test at age 28 weeks (p ...Chicks require heat to maintain body temperature during the first weeks after hatch. This may be provided by dark brooders; i.e., horizontal heating elements equipped with curtains. The objective was to test effects of rearing layer chicks with dark brooders on time budget and fearfulness....... Behavioral observations were performed during the first six weeks of age. Three different fear tests were conducted when the birds were age 3–6, 14–15 and 26–28 weeks. During the first four days, brooder chicks rested more than control chicks whereas they spent less time drinking, feather pecking...
Avise, John C; Tatarenkov, Andrey; Liu, Jin-Xian
We summarize the genetic literature on polygamy rates and sire numbers per clutch in invertebrate animals that brood their offspring and then compare findings with analogous data previously compiled for vertebrate species displaying viviparity or other pregnancy-like syndromes. As deduced from molecular parentage analyses of several thousand broods from more than 100 "pregnant" species, invertebrate brooders had significantly higher mean incidences of multiple mating than pregnant vertebrates, a finding generally consistent with the postulate that clutch size constrains successful mate numbers in species with extended parental care. However, we uncovered no significant correlation in invertebrates between brood size and genetically deduced rates of multiple mating by the incubating sex. Instead, in embryo-gestating animals otherwise as different as mammals and mollusks, polygamy rates and histograms of successful mates per brooder proved to be strikingly similar. Most previous studies have sought to understand why gestating parents have so many mates and such high incidences of successful multiple mating; an alternative perspective based on logistical constraints turns the issue on its head by asking why mate numbers and polygamy rates are much lower than they theoretically could be, given the parentage-resolving power of molecular markers and the huge sizes of many invertebrate broods.
Viladrich, Núria; Bramanti, Lorenzo; Tsounis, Georgios; Chocarro, Blanca; Martínez-Quitana, Angela; Ambroso, Stefano; Madurell, Teresa; Rossi, Sergio
This study investigates the energetic investment during spawning of two Mediterranean gorgonians characterized by different reproductive strategies: Corallium rubrum (internal brooder) and Paramuricea clavata (surface brooder). Sexual products (number of oocytes and spermatic sacs) were quantified, and biochemical characteristics (lipid content and free fatty acid content and composition) were determined to investigate the parental energetic investment and demand in reproduction. Results suggested that the majority of the energetic cost was due to reproductive activity (i.e., gametogenesis and spawning). The two species exhibited different life history strategies, with P. clavata investing more energy in reproduction than C. rubrum. However, P. clavata is reproductively more sensitive to inter-annual changes in environmental conditions.
Isolamento de enterobactérias em Alphitobius diaperinus e na cama de aviários no oeste do estado do Paraná, Brasil Isolation of enteric and litter organisms from Alphitobius diaperinus in brooder chickens houses in west of Parana State, Brazil
Full Text Available O objetivo deste trabalho foi realizar o isolamento de bactérias da família Enterobacteriaceae em adultos de A. diaperinus, buscando uma correlação entre as bactérias presentes no inseto e na cama, em aviários para produção de frangos de corte no oeste do Paraná, Brasil. No primeiro experimento, insetos adultos foram coletados em 14 granjas. No segundo experimento, foram coletados insetos e material da cama de 12 diferentes aviários. Os adultos foram anestesiados com éter, macerados em solução salina e o material da cama colhido por "swab" de arrasto. O enriquecimento não seletivo foi feito com caldo BHI e o seletivo com Rappaport-Vassiliadis e Tetrationato. Os meios de cultivo para plaqueamento foram o ágar MacConkey, ágar Salmonella-Shigella e ágar verde-brilhante. As enterobactérias isoladas em adultos de A. diaperinus foram: Proteus Vulgaris, P. mirabilis, Escherichia Coli, Enterobacter spp., E. agglomerans, E. gergoviae, E. sakasakii, Citrobacter Diversus e Klebsiella Pneumoniae, enquanto que na cama foram encontrados Proteus Vulgaris, P. mirabilis, Escherichia Coli, Enterobacter Agglomerans. Não foram isoladas Salmonella spp. do inseto nem da cama e P. vulgaris foi a predominante. E. coli foi freqüente nas granjas, tanto na cama como nos insetos e contribuem na disseminação da colibacilose em aviários.This study was conducted to determine bacterial species of Enterobacteriaceae in adults of lesser mealworm, A. diaperinus and make the correlation of the bacterial species in the insects and in the litter that infest poultry brooder houses in West of Parana State, Brazil. In the first experiment, the adults were collected in 14 poultry houses. In the second experiment the insects and the litter were collected in 12 poultry houses. The adults were anaesthetized with eter, macerated in sterile saline solution and the litter material was taken off by swab. The enrichment broth was plated on the BHI and in Rappaport
LIU Xiande; SUI Banliang; WANG Zhiyong; CAI Mingyi; YAO Cuiluan; CHEN Qingkai
We estimated the reproductive success of adult brood fish and the heritability of growthrelated traits for large yellow croaker (Larimichthys crocea).We created two independent full-factorial cross groups (1 and 2) by crossing 4 males×4 females and 4 males×3 females,respectively.We measured the body weight (BW),body length (BL),and body height (BH) of 281 individuals from group 1 and 318 individuals from group 2 at 20 months post hatch (harvest age).We also collected a tissue sample from each individual.The parents and offspring were genotyped using six polymorphic microsatellites.Of the 599 offspring,99.2％ were assigned to a single pair of parents.In both groups,some parent pairs produced a large number of offsprings while other pairs did not produce any offspring.The genetic diversity and putative Ne were lower in the offsprings than in the parents in both groups.The heritability estimates at 20-month age were 0.13±0.10 for BW,0.19±0.13 for BL,and 0.09±0.06 for BH.The genetic and phenotype correlation between BW,BL,and BH was close to 1.The results provide basic information for selective breeding and further genetic characterization of large yellow croaker.
江世贵; 翁少萍; 吕玲; 苏天风; 何建国
感染白斑综合症病毒(white spot syndrome virus,WSSV)的斑节对虾Penaeus monodon亲虾能产出携带WSSV的卵子,这些卵子可完成胚胎发育过程、孵化出无节幼体,并可以培育出蟤状幼体、糠虾幼体和仔虾.在确认只有亲虾作为WSSV传染源的情况下,培育出的部分幼体和部分仔虾携带WSSV;在相同的条件下,不带WSSV的亲虾产出的卵及幼体、仔虾未检测到WSSV.
Full Text Available During the breeding season, lots of physiological changes occur in the bodies of fish which lead to other phenotypical, anatomical and behavioral changes. To evaluate the impact of breeding on the bodily composition of fish, tests were conducted to determine the fatty acid profile of the brooder and Non-brooder wild and farmed fish. Samples were analyzed by gas liquid chromatography using a flame ionization detector.There are non significant differences in the amount of saturated and unsaturated fatty acids in wild and farmed nonbrooder fish whereas in case of brooder there are significant differences. Brooder farmed fish contained more saturates in gonads approximately twice that of wild fish with C16:0 as the dominating fatty acid. C18:2n-6 and C20:5n-6 were the dominating unsaturated fatty acids in the gonads. Non-brooder fish contained more unsaturated fatty acids in the meat as compared to the brooder fish and farmed fish contained higher amounts of saturated fatty acids as compared to wild fish. C18:1n-9 and C20:4n-6 fatty acids were found in higher quantities and among the saturated acids, C16:0 is the dominating one. More or less similar results were found in the case of the liver fatty acid profile of breeding and nonbreeding fish. Fish of lower weight categories contained more unsaturated fatty acids and so better for consumption to leave the brooders of higher weight categories for the breeding of future generation.Durante la época de reproducción numerosos cambios fisiológicos ocurren en el cuerpo de los peces que guían a cambios anatómicos y de comportamiento. Para evaluar el impacto de la etapa de reproducción en la composición de los peces, ensayos para determinar el perfil de ácidos grasos fueron conducidos en peces salvajes y criados, en dos categorías de peso, maduro (booder o inmaduro (non-brooder. Las muestras fueron analizadas por cromatografía de gases usando un detector de ionización de llama. No hubo
Fleming, W.J.; Heinz, G.H.; Franson, J.C.; Rattner, B.A.
Diets mixed to contain 0,0.1, 1.0, 10 and 100 ppm temephos (determined chemically to contain less than 0.5, less than 0.5, 0.89, 6..0 and 59 ppm temephos, respectively) in an Abate ? 4E formulation, were fed to mallard (Anas platyrhynchos) ducklings for 7 d. During this period, half of the ducklings in each dietary treatment group were housed in a heated brooder (39 to 41?C) and half were housed in an unheated brooder (10 to 18?C). Mortality in all dietary groups in the unheated brooder was higher than in the heated brooder. High temephos-related mortality occurred in the 100 ppm group in the unheated brooder but not in any other diet-temperature groups. Ingestion of the 100 ppm temephos diet inhibited plasma cholinesterase (ChE) activity and elevated plasma corticosterone concentration and creatine phosphokinase activity, but other selected plasma chemistries were not affected in a dose-related manner. Brain ChE activity was depressed only in the 100 ppm dietary groups; maximum inhibition of brain ChE activity was 48%. These findings suggest that diets containing up to 10 ppm temephos do not directly affect duckling survival during the first week of life and that the toxicity of 100 ppm temephos is markedly enhanced by cold.
Full Text Available In aquaculture species, maintaining pedigree information and genetic variation in each generation is essential, but very difficult. In this study, we used nine microsatellites to genotype 2,520 offspring from four independent full-factorial crosses (10 males × 10 females of Asian seabass to reconstruct pedigree and monitor the change of genetic variations. In all four crosses, over 96.8% of the offspring could be assigned to their parents, indicating the high power of the nine microsatellites for parentage assignment. This study revealed several interesting results: (1. In all four crosses, the contribution of parents to offspring was significantly uneven, and some dominant breeding fishes (i.e. brooders were found; (2. In two mass crosses where the brooders were carefully checked for reproductive status, a majority (≥ 90% of brooders contributed to offspring, whereas in another two crosses, where the brooders were randomly picked without checking reproductive status, only a few brooders (40.0-45.0% produced offspring; (3. Females had more problems in successful spawning compared to males; and (4. In the two crosses where a few brooders produced offspring, there was a substantial loss in allelic (24.1-34.3% and gene (20.5-25.7% diversities in offspring, while in the other two crosses, the majority of allelic (96.8-97.0% and gene diversities (94.8-97.1% were maintained. These observations suggest that a routine molecular parentage analysis is required to maintain both allelic and gene diversity in breeding Asian seabass.
Ochieng, Justus; Owuor, George; Bebe, Bockline Omedo
In Africa, many rural farming households keep indigenous chickens (Gallus domesticus) in traditional scavenging systems characterized by low input and low output. To improve productivity, African governments and development partners disseminate a management intervention package consisting of feed supplementation, vaccination, brooder, chick rearing equipment and improved housing. Some smallholder farmers adopt the full package, while others adopt the feed supplementation and vaccination only,...
@@ Shiyan Dongfeng Innovation,Brooder, Industrial Zone Ⅰ. The Background of The Project and the Enterprise The project is located at Xiejia Val-lage, Checheng Sub-district, Kaixuan Avenue, invested by Xianglong Real Estate Co., Ltd. It covers an area of 82.3 acres.
Viblanc, Vincent A; Gineste, Benoit; Stier, Antoine; Robin, Jean-Patrice; Groscolas, René
Because glucocorticoid (stress) hormones fundamentally affect various aspects of the behaviour, life history and fitness of free-living vertebrates, there is a need to understand the environmental factors shaping their variation in natural populations. Here, we examined whether spatial heterogeneity in breeding territory quality affected the stress of colonial king penguin (Aptenodytes patagonicus). We assessed the effects of local climate (wind, sun and ambient temperature) and social conditions (number of neighbours, distance to neighbours) on the baseline levels of plasma total corticosterone (CORT) in 77 incubating and 42 chick-brooding birds, breeding on territories of central or peripheral colony location. We also assessed the oxidative stress status of a sub-sample of central vs. peripheral chick-brooders to determine whether chronic stress arose from breeding on specific territories. On average, we found that brooders had 55% higher CORT levels than incubators. Regardless of breeding status, central birds experienced greater social density (higher number of neighbours, shorter distance between territories) and had higher CORT levels than peripheral birds. Increasing social density positively explained 40% of the variation in CORT levels of both incubators and brooders, but the effect was more pronounced in brooders. In contrast, climate was similar among breeding territories and did not significantly affect the CORT levels of breeding birds. In brooders, oxidative stress status was not affected by local density or weather conditions. These results highlight that local heterogeneity in breeding (including social) conditions may strongly affect the stress levels of breeding seabirds. The fitness consequences of such variation remain to be investigated.
Nizamettin Senkoylu; Hasan Akyurek; Fisun Koc; Aylin Agma Okur; Hasan Ersin Samli; Mehmet Levent Ozduven
The experiment was conducted to evaluate the effects of organic acid mixture and/or mannanoligosaccharides (MOS) on growth performance, blood parameters and intestinal microbiota in 120 Ross 308 male broiler chicks, over a period of 21 days. Birds were maintained in battery brooders confined in an environmentally controlled experimental room. There were 4 dietary treatments, each consisting of 6 replicates. Dietary treatments were: (i) basal diet (as a control), (ii) basal diet + MOS 2 kg/ton...
This study was conducted to investigate the effect of mineral biofortified wheat with fungal phytase addition on iron (Fe) and zinc (Zn) availability in broiler chicken breast muscle and liver, their excretion in feces and digestibility in intestines. Furthermore, possible beneficial effect on broiler performance was studied. 90 day-old Ross 308 broiler chickens were placed in brooder cages and received commercial starter diet from day 1-7 posthatch and micromineral deficient s...
Zhu, W; Jiang, W; Wu, L Y
The current intensive indoor production system of commercial Pekin ducks never allows adequate water for swimming or wetting. Therefore, heat stress is a key factor affecting health and growth of ducks in the hot regions and season. Experiment 1 was conducted to study whether heat stress was deleterious to certain organs of ducks. Forty-one-day-old mixed-sex Pekin ducks were randomly allocated to four electrically heated battery brooders comprised of 10 ducks each. Ducks were suddenly exposed to 37 °C ambient temperature for 3 h and then slaughtered, in one brooder at 21 days and in another brooder at 49 days of age. The results showed that body weight and weight of immune organs, particularly liver markedly decreased in acute heat stress ducks compared with the control. Experiment 2 was carried out to investigate the influences of dietary L-arginine (Arg) supplement on weight and compositions of certain lymphoid organs, and growth performance in Pekin ducks, under daily cyclic hot temperature environment. A total of 151-day-old mixed-sex Pekin ducks were randomly divided into one negative control and two treatment groups, fed experimental diets supplemented with 0, 5, and 10 g L-Arginine (L-Arg)/kg to the basal diet respectively. Ducks were exposed to cyclic high temperature simulating natural summer season. The results showed that the addition of L-Arg improves feed conversion ratio (FCR) during a period of 7-week trial, as well as increases hepatic weight relative to body weight at 21 days, while decreases the hepatic water content at 49 days of age. This study indicated that the liver was more sensitive to acute heat stress, and the hepatic relative weight and chemical composition could be regulated by dietary L-Arg supplementation in Pekin ducks being reared at high ambient temperature. These beneficial effects of Arg on liver might be a cause of improved FCR.
Shuster, Katherine A; Brock, Kristie L; Dysko, Robert C.; DiRita, Victor J.; Bergin, Ingrid L
Two groups of chickens (Gallus domesticus; White Leghorn; age, 4 d and 2 wk) housed in a university research vivarium were found dead or moribund without prior signs of illness. The overall mortality rates were 92.3% (60 of 65 birds) for the 4-d-old birds and 80% (8 of 10) for the 2-wk-old birds. All chicks were housed in brooders with heat lamps in a temperature- and humidity-controlled room. Primary gross findings were mild to moderate dehydration and hepatic lipidosis. The most consistent ...
B. Indarsih; R.A.E.Pym
The study was conducted as a completely randomized design, with a factorial arrangement to determine the response of commercial broilers to choice feeding and limiting amino acids on growth and carcass performance. A total of 432 male birds were weighed at one-d-old and randomly distributed to 48 wire-floored brooder cage each 1.0 m2. There were 2 sexes and 4 dietary treatments with 6 replicates each of 9 birds. Birds were given one of three dietary regimens with dietary change every 7 days. ...
The response of Cobb and Ingham strain commercial broilers to a range of dietary amino acids in a factorial experiment (2 strains x 2 sexes x 3 dietary treatments) with 3 replicates was evaluated. A total of 180 birds was sexed and weighed at one-day-old and randomly distributed to 36 brooders. Summit (246 g CP and 16.8 g lysine/kg) and dilution (120 g CP and 6.0 g lysine/kg) diets were prepared in isocaloric at 3100 kcal ME/kg. The estimated dietary level of crude protein for all birds at da...
Chineke THEO CHIDIEZIE
Full Text Available Obvious is the fact that globally the climate is changing. Solar energy and water availability are the key factors affecting agricultural productivity in Subtropical Africa. In this paper is presented the global radiation for Owerri, Nigeria (latitude 5.48oN, longitude 7.03oE between 1985-1997 which has a mean annual value of 76.17 W/m2 per day. With appropriate crop specie selection and management, food production, including poultry output can be boosted in this high solar radiation area. The introduction of solar egg incubator, solar manure dryer and brooder has been strongly advocated.
Foltz, David W; Mah, Christopher L
Patterns of nucleotide substitution differ between marine species that have a pelagic feeding (planktotrophic) larval stage and related species that lack such a stage, for both adaptive and non-adaptive reasons. Here, patterns of nucleotide and inferred amino acid substitution are analyzed for the tandem-repetitive early-stage histone H3 gene in 36 sea star species of the order Forcipulatida with documented larval habitat. The relative rate of nonsynonymous substitution (expressed as ω=d(N)/d(S)) was significantly higher in lineages with a brooded non-feeding (lecithotrophic) larval form than in lineages with a planktotrophic larval form. There was also a significant excess of conservative over radical substitutions. The increase in ω for brooders as compared to non-brooders was much greater than for previously analyzed mitochondrial sequences in echinoderms. These data are consistent with the hypothesis that purifying selection on this gene has been relaxed in brooding lineages compared to non-brooding lineages. The hypotheses of adaptive or neutral evolution are less plausible, although recent pseudogenization following a period of relaxed purifying selection could also explain the results.
Basavaraja, N; Chandrashekhara, B H; Ahamad, Rather Mansoor
Norethindrone(NE) was evaluated for its efficacy on alteration of sex ratio of P. reticulata. Either the young fry or the brooders and the resultant fry were fed a commercial diet incorporated with NE at 0, 25, 50, 75 and 100 mg kg(-1) diet (ppm) for 30-40 d in rectangular glass aquaria; this was followed by 40-60 d rearing on NE-free diet in out-door concrete tanks. In general, the androgen treatment altered sex ratio, leading to the production of a dose dependent increase in the percentage of males. The oral administration of the steroid at 75 ppm for 40 d or 100 ppmfor 30 or 40 d to first feeding fry, yielded 100% males. On the other hand, NE administration to brooders before parturition and the resultant fry also produced an all-male population of guppy. The sex ratio of the untreated control was almost 1:1. The survival of fish in all the trials was high, ranging between 67 and 100%. Mating masculinized males ("XX" male) with normal female resulted in an all-female progeny, while crossing normal male (XY) from treatment groups with normal female sired normal sex ratio (1:1), elucidating XX-XY sex determination system in the guppy.
Full Text Available A study was conducted to evaluate the effect of age of release, strain and farmers location on growth and carcass performance of the indigenous, and two exotic strains (Harco® and Goldline® cockerels, reared on free range; in order to ascertain the best age of release into free range from brooder houses, as well as the effect of farmers location and strain on their growth and carcass characteristics, in South Eastern Nigeria. A total of 315 cockerels comprising 87 indigenous chicks, 114 Harco® chicks, and 114 Goldline® cockerels brooded and raised up to 18 weeks of age were used in this experiment. These birds were randomly released to farmers in the villages at three different ages of 4, 8 and 12 weeks to run on free range. There were significant effects of age of release and strain on the growth characteristics, but none on the carcass characteristics. However, there was also significant effect of the zone on both growth and carcass traits measured. It was concluded that the earlier the exotic birds are released from the brooder house, the better their performance on scavenging rearing. This is beneficial as the farmer will save much from the purchase of compounded feed and other veterinary services.
Olsen, K.; Sneed, J. M.; Paul, V. J.
Settlement is critical to maintaining coral cover on reefs, yet interspecific responses of coral planulae to common benthic macroalgae are not well characterized. Larval survival and settlement of two Caribbean reef-building corals, the broadcast-spawner Acropora palmata and the planulae-brooder Porites astreoides, were quantified following exposure to plastic algae controls and the green macroalga Halimeda opuntia. Survival and settlement rates were not significantly affected by the presence of H. opuntia in either species. However, ~10 % of P. astreoides larvae settled on the surface of the macroalga, whereas larvae of A. palmata did not. It is unlikely that corals that settle on macroalgae will survive post-settlement; therefore, H. opuntia may reduce the number of P. astreoides and other non-discriminatory larvae that survive to adulthood. Our results suggest that the presence of macroalgae on impacted reefs can have unexpected repercussions for coral recruitment and highlight discrepancies in settlement specificity between corals with distinct life history strategies.
Embryonic development, hatching, mineral consumption, and survival of Macrobrachium rosenbergii (de Man reared in artificial seawater in closed recirculating water system at different levels of salinity
Full Text Available This experiment aims to study the effect of different levels of salinity (5, 15 and 25 ppt using artificial sea water on the embryonic development and hatching percentage of the eggs of unripe berried female giant freshwater prawns (Macrobrachium rosenbergii with an average size of 14.3+0.6 cm TL. After incubation through the heart beating stage (grayish black eggs, the brooders in each salinity were separately transferred to the hatching tank with 15 ppt saline water for the second part of the study. After hatching, the healthy larvae from the brooders which were previously incubated in 3 levels of salinity were collected for the larviculture experiment. The closed recirculating water system with trickling filter unit packed with fiberglass and bioballs was used as incubation and larviculture units. The metamorphosis period and survival rate were examined. The rearing water from each larviculture aquarium was collected for determination of sodium, magnesium, potassium, calcium and chloride ions. The result showed that the percentage of ripe berried females (with heart beating stage embryos were not significantly different (p>0.05 between 5 and 15 ppt salinity but their values were significantly higher (p0.05 in the survival rate of post larvae and metamorphosis period among the treatments. The first post larvae stage occurred on the 26th day. During 30 days of larviculture, the survival rate of all treatments was 100% until the 19th day, after which it suddenly decreased. When the concentrations of the ions in the rearing water were determined in all treatments, it was found that the concentration of magnesium ions rapidly declined (p0.05. The low survival rate during the final stage of larviculture might be due to the depletion of the previously mentioned ions especially that of magnesium.
Poulin, Elie; González-Wevar, Claudio; Díaz, Angie; Gérard, Karin; Hüne, Mathias
Continental drift processes such as major gateway openings have been historically advocated to explain the distribution of marine benthic taxa in the Southern Ocean (SO). The separation between Antarctic Peninsula and the southern tip of South America together with the onset of the Antarctic Circumpolar Current (ACC) represent the final step for the complete isolation of the Antarctic region. However, there is still controversy concerning the timing and mode of this process, and especially about the role of the Scotia Arc geodynamics in the development of a fully deep and intensified ACC circulation. Based on mitochondrial Cytochrome c Oxidase Subunit I (COI) sequences obtained from different taxa, we performed molecular comparisons between Antarctic and South American relatives to provide independent time estimations of Antarctica's isolation. We include in the analyses congeneric Antarctic and Patagonian near-shore marine benthic invertebrates including indirect developers (Nacella, Yoldia, Sterechinus, and Parbolasia) and brooders (Xymenopsis and Trophonella). Considering the levels of genetic differentiation between relatives from both regions and assuming the molecular clock hypothesis, we estimated the onset of their respective divergence. On one hand, similar levels of genetic distance in broadcast-spawners (7%-8.3%) support the hypothesis that the development of an effective barrier between Antarctica and South America occurred almost simultaneously for these groups. Divergence time estimations based on specific substitution rates indicate that the separation occurred near the Mio-Pliocene transition, long after the physical separation of both continents. Genetic distance and divergence time estimation in direct developers indicate an older separation time, close to the mid-Miocene. Even when the analyzed groups included both broadcast-spawners and brooder organisms, the divergence between Antarctic and South America lineages rather than being related to
Venkatachalam Uthayakumar; Parathattil Rathan Sreedevi; Dhanapalan Senthilkumar; Subramanian Munirasu; Aathi Kiruba; Venkatachalam Ramasubramanian
Objective: To analyze the effect of seasonal variation and nutritional factors over the fecundity, gonado somatic index (GSI) and sperm motility of fresh water spiny eel Mastacembelus armatus (M. armatus) under artificial cave fitted tanks in laboratory condition. Methods: Forty pairs of M. armatus were collected from River Cauvery and are acclimated under lab condition. The fishes were fed with three different feeds like Fresh water prawns, earthworms and fish larvae for 60 days. Fecundity, sperm motility, Length weight relationship and GSI were analysed using standard procedures. Results: The fecundity rate was increased when body weight and gonad weight increased. The lograthemic relationship of the fecundity-total length and fecundity-body weight were found to be more correlated than the fecundity-gonad weight relationship. Maximum GSI was recorded in both male and female fishes during the breeding season (June-October). The condition factor (K) was maximum at the non breeding seasons and reduced in peak breeding season of M. armatus. In male fishes the sperm motility was recorded maximum (70%-85%) in the breeding season and regressed gradually to 0-15%. Among the feeding groups earthworm fed group showed higher body weight and fecundity rate than the control group which was statistically significant at P <0.05 level. Conclusion: The outcome of the present study shows the seasonal variation and feeding increase the reproductive performance. It can be effectively used for the healthy brooder selection, captive breeding and conservation of M. armatus.
Holstein, Daniel M.; Paris, Claire B.; Vaz, Ana C.; Smith, Tyler B.
Whether mesophotic reefs will behave as refugia for corals threatened by global climate change and coastal development depends on vertical exchange of larvae between diverse habitats. Here we use a biophysical model of larval dispersal to estimate vertical connectivity of a broadcasting ( Orbicella faveolata) and a brooding ( Porites astreoides) species of coral in the US Virgin Islands. Modeling predicts subsidy to shallow areas by mesophotic larvae of both species based on local hydrology, adult reproductive characteristics, larval traits, and a wide range of scenarios developed to test depth-sensitive factors, such as fertilization rates and post-settlement survivorship. In extreme model scenarios of reduced fertilization and post-settlement survivorship of mesophotic larvae, 1-10 % local mesophotic subsidy to shallow recruitment is predicted for both species, which are demographically significant. Although direct vertical connectivity is higher for the broadcaster, the brooder demonstrates higher local multigenerational vertical connectivity, which suggests that local P. astreoides populations are more resilient than those of O. faveolata, and corroborates field studies. As shallow habitat degrades, mesophotic-shallow subsidy is predicted to increase for both species. This study is the first of its kind to simulate larval dispersal and settlement between habitats of different depths, and these findings have local, regional, and global implications for predicting and managing coral reef persistence in a changing climate.
Full Text Available The study was conducted as a completely randomized design, with a factorial arrangement to determine the response of commercial broilers to choice feeding and limiting amino acids on growth and carcass performance. A total of 432 male birds were weighed at one-d-old and randomly distributed to 48 wire-floored brooder cage each 1.0 m2. There were 2 sexes and 4 dietary treatments with 6 replicates each of 9 birds. Birds were given one of three dietary regimens with dietary change every 7 days. All groups were fed free choice of summit and dilution diets. The estimated dietary level of crude protein at day-old was 240 g/kg and the level at 42 d was either 120, 150 or 180 g/kg for females or 130, 160 and 190 g/kg for males. At 43 d of age, all birds from each dietary treatment were slaughtered for measurement of body composition. Results reveal that lysine requirement for maximum gain in this study was higher than NRC recommendation. The free choice-fed bird was significantly higher, in terms of growth and body composition than that obtained on the low dietary protein regimen.Keyword
Drake, P.; Arias, A. M.
The ichthyoplankton of a shallow inlet was sampled for 13 months using conical tide-strained nets. The utilization of this habitat by the young stages of different fish species is analysed. Temporal and spatial distributions are discussed in relation to environmental cycles and gradients, and to feeding rhythms. A total of 110 971 individuals, belonging to 39 species and 19 families of teleosts, was collected. The postlarval stage was the most represented in the samples. Ichthyoplankton density peaked during late winter and early spring. Density was higher during flood tide, resulting in a net input of postlarvae from the bay to the inner inlet. This ecosystem functions primarily as a nursery ground for coastal pelagic spawners and, secondarily, as a spawning area for some benthic egg spawners and pouch-brooder species. Most postlarvae migrate from their spawning area (open sea) to the inlet probably cued by a decreasing gradient of water temperature and salinity, and an increasing gradient of water turbidity and suitable food concentration. The attraction of postlarvae towards the inlet mouth probably results from a combination of biotic (availability of suitable food) and abiotic (temperature, salinity and turbidity) factors. Passive transport contributes to the subsequent penetration and retention of the postlarvae within the shallow, flood-dominated inlet. Vertical migrations observed among some planktonic fish stages were related to light periods and feeding activity rather than tidal phases, and cannot act as a retention mechanism.
Helena Phoenix Baird
Full Text Available Currently there is very limited understanding of genetic population structure in the Antarctic benthos. We conducted one of the first studies of microsatellite variation in an Antarctic benthic invertebrate, using the ubiquitous amphipod Orchomenella franklini (Walker, 1903. Seven microsatellite loci were used to assess genetic structure on three spatial scales: sites (100 s of metres, locations (1-10 kilometres and regions (1000 s of kilometres sampled in East Antarctica at Casey and Davis stations. Considerable genetic diversity was revealed, which varied between the two regions and also between polluted and unpolluted sites. Genetic differentiation among all populations was highly significant (F(ST = 0.086, R(ST = 0.139, p<0.001 consistent with the brooding mode of development in O. franklini. Hierarchical AMOVA revealed that the majority of the genetic subdivision occurred across the largest geographical scale, with N(em≈1 suggesting insufficient gene flow to prevent independent evolution of the two regions, i.e., Casey and Davis are effectively isolated. Isolation by distance was detected at smaller scales and indicates that gene flow in O. franklini occurs primarily through stepping-stone dispersal. Three of the microsatellite loci showed signs of selection, providing evidence that localised adaptation may occur within the Antarctic benthos. These results provide insights into processes of speciation in Antarctic brooders, and will help inform the design of spatial management initiatives recently endorsed for the Antarctic benthos.
Lucey, Noelle Marie; Lombardi, Chiara; Demarchi, Lucia; Schulze, Anja; Gambi, Maria Cristina; Calosi, Piero
Anthropogenic atmospheric carbon dioxide (CO2) is being absorbed by seawater resulting in increasingly acidic oceans, a process known as ocean acidification (OA). OA is thought to have largely deleterious effects on marine invertebrates, primarily impacting early life stages and consequently, their recruitment and species’ survival. Most research in this field has been limited to short-term, single-species and single-life stage studies, making it difficult to determine which taxa will be evolutionarily successful under OA conditions. We circumvent these limitations by relating the dominance and distribution of the known polychaete worm species living in a naturally acidic seawater vent system to their life history strategies. These data are coupled with breeding experiments, showing all dominant species in this natural system exhibit parental care. Our results provide evidence supporting the idea that long-term survival of marine species in acidic conditions is related to life history strategies where eggs are kept in protected maternal environments (brooders) or where larvae have no free swimming phases (direct developers). Our findings are the first to formally validate the hypothesis that species with life history strategies linked to parental care are more protected in an acidifying ocean compared to their relatives employing broadcast spawning and pelagic larval development.
Langhout, D J; Schutte, J B
An experiment was conducted to examine the effect of feeding high-methylated (HM) and low-methylated (LM) pectin on performance and physiological characteristics in broiler chicks. Two levels each (1.5 and 3%) of HM citrus pectin (HMC), LM citrus pectin (LMC), or HM sugar beet pectin (HMS) were added to a semi-purified basal diet. The experiment was conducted in battery brooders, and chicks received the diets as pellets from 6 to 27 d of age. The inclusion of LMC or HMS in the diet had little or no effect on the performance of chicks; however, when HMC was added to the diet growth and feed utilization were reduced significantly (P Waterholding capacity of the diets and the excreta were increased significantly by including one (P 0.05) on the concentration of VFA. In contrast, inclusion of HMS in the diet significantly increased the concentration of VFA in the cecal content (P < 0.05) dose-dependently. Based on the results of the present study, it can be concluded that the effect of dietary pectin on chick performance is dependent on the degree of carboxyl groups that is esterified, the origin of the pectin product, and the amount added to the diet.
Full Text Available Amphiprion sebae kept in the recirculating Marine Research Aquarium spawned a maximum of 0.8 times per month throughout the year. This is the first spawning record from a recirculating aquarium environment. Generally the spawning of A. sebae has been described from fresh seawater by various authors. The present study mainly observes the maintenance of brooders, their pairing and spawning in recirculating aquarium environment. Among the 54 adult fishes collected from the natural environment, three pairs are formed in the aquaria. The parental care of egg guarding male was observed. Three pairs are fed with different feed i.e., prawn meat, fish meat and a combination of prawn, fish and clam meats. The spawning frequency was observed to be moderately high (0.8/month when fed with the mixed feed, whereas a frequency of 0.5 and 0.6 per months was observed when fed with prawn, fish meats respectively. The maximum clutch size (911 was observed also in mixed feeds and it was minimum (395 when the pairs were fed with fish meat alone. The increase in the frequency of spawning was during summer months compared to other months.
Full Text Available The response of Cobb and Ingham strain commercial broilers to a range of dietary amino acids in a factorial experiment (2 strains x 2 sexes x 3 dietary treatments with 3 replicates was evaluated. A total of 180 birds was sexed and weighed at one-day-old and randomly distributed to 36 brooders. Summit (246 g CP and 16.8 g lysine/kg and dilution (120 g CP and 6.0 g lysine/kg diets were prepared in isocaloric at 3100 kcal ME/kg. The estimated dietary level of crude protein for all birds at day-old was 240 g/kg and at 42 days were 120, 140 or 160 g/kg for females or 140, 160 or 180 g/kg for males. Body composition was measured at 42 days. Results revealed that strain Cobb males and females had a higher daily intake than Ingham, but Cobb females were less efficient in converting feed to weight gain than that of Ingham. The quantitative differences did not exist between genotypes, crude protein and lysine. Daily gain and feed utilization efficiency in both sexes were highest in group receiving the high protein diet. Lysine requirement was 14.58 g lysine /kg diet and 12.96 g/kg higher than NRC recommendation (1.05 % or 10.5 g/kg for maximum breast meat and lowest abdominal fat.
Full Text Available The study was conducted as a completely randomized design, with a factorial arrangement todetermine the response of commercial broilers to choice feeding and limiting amino acids on growth andcarcass performance. A total of 432 male birds were weighed at one-d-old and randomly distributed to48 wire-floored brooder cage each 1.0 m2. There were 2 sexes and 4 dietary treatments with 6 replicateseach of 9 birds. Birds were given one of three dietary regimens with dietary change every 7 days. Allgroups were fed free choice of summit and dilution diets. The estimated dietary level of crude protein atday-old was 240 g/kg and the level at 42 d was either 120, 150 or 180 g/kg for females or 130, 160 and190 g/kg for males. At 43 d of age, all birds from each dietary treatment were slaughtered formeasurement of body composition. Results reveal that lysine requirement for maximum gain in thisstudy was higher than NRC recommendation. The free choice-fed bird was significantly higher, in termsof growth and body composition than that obtained on the low dietary protein regimen.
Chee, San-San Amy; Espinoza, Walter A S; Iwaniuk, Andrew N; Pakan, Janelle M P; Gutiérrez-Ibáñez, Cristian; Wylie, Douglas R; Hurd, Peter L
Gonadotropin-releasing hormone (GnRH) expressing neurons in the preoptic area (POA) of the hypothalamus plays a key role in regulating reproductive function through the control of gonadotropin release. Several studies have illustrated the importance of the social environment in modulating the size of GnRH expressing neurons. In the African cichlid fish Astatotilapia burtoni, the size of the soma of GnRH expressing neurons in the POA varies with social status in males, and with breeding state in females. Territorial males have larger GnRH+ cells than non-territorial males, while brooder females have smaller GnRH+ cells than control females. The lek-like breeding system of A. burtoni is, however, only one type of social system within the diverse assemblage of cichlids. To gain a better understanding of GnRH neuronal plasticity in response to the changes in the social environment, we tested whether similar effects occur in the monogamous New World cichlid, the convict cichlid (Cryptoheros nigrofasciatus), a model species for the study of social behaviour. Our results indicate that, indeed GnRH expressing neuron soma size, and not cell number, varies with both male territorial status, and manipulations of female breeding state in this monogamous, biparental, New World cichlid.
Betancourt, Liliana; Rodriguez, Fernando; Phandanouvong, Vienvilay; Ariza-Nieto, Claudia; Hume, Michael; Nisbet, David; Afanador-Téllez, German; Van Kley, Alexandra Martynova; Nalian, Armen
Essential oils have been proposed as alternatives to antibiotic use in food animal production. This study evaluated 3 chemotypes of the Origanum genus, containing varying amounts of secondary metabolites carvacrol, thymol, and sabinene, in the broiler chicken diet. Aerial parts of Origanum vulgare L. (OL), O. vulgare L. ssp. hirtum (OH), and O. majorana (OM) were collected from a greenhouse located in the high altitude Sabana de Bogotá (Savanna of Bogotá) and O. vulgare L. ssp. hirtum (OG) produced and ground in Greece. Oregano essential oils (OEO) from these plants were obtained by steam distillation and analyzed by gas chromatography coupled to a mass spectrometer. Six treatments were evaluated: 200 mg/kg of OEO from OH, OL, and OM, 50 mg/kg of OEO from OG, 500 mg/kg of chlortetracycline, and without additives. Broiler chicks were maintained at 2,600 m above sea level, placed in brooder cages under a completely randomized design. Template DNA was isolated from duodenal, jejunal, ileal, and cecal contents in each group and bacterial 16S rDNA patterns were analyzed by denaturing gradient gel electrophoresis. Dendrograms of denaturing gradient gel electrophoresis band patterns revealed 2 main clusters, OEO-treated chicks and nontreated control chicks, in each intestinal segment. Band patterns from different gut compartments revealed major bacterial population shifts in the foregut (duodenum, jejunum, and ileum) compared with the hindgut (cecum and colon) at all ages evaluated (P < 0.05). The OEO groups showed less shift (62.7% similarity coefficient) between these 2 compartments versus the control groups (53.7% similarity coefficient). A reduction of 59% in mortality from ascites was seen in additive-supplemented groups compared with the control group. This study represents the first work to evaluate the effects of the 3 main chemotypes of Origanum genus in broilers. PMID:25071230
DHANEESH Kottila Veettil; AJITH KUMAR Thipramalai Thankappan; SWAGAT Ghosh; BALASUBRAMANIAN Thangavel
Breeding and mass scale larval rearing of clownfish Amphiprion percula is very limited in brackishwater.We designed an indoor program of A.percula culture in brackishwater with a salinity of 24±1,during which the impacts of feed type,water temperature,and light intensity,on the efficiency of its reproduction,were revealed.The fish were accommodated along with sea anemones in fibre glass tanks to determine the influence of brooder diet on breeding efficiency.Higher reproductive efficiency [number of eggs laid (276±22.3 eggs)] was observed when fish were fed live Acetes sp.rather than clam (204±16.4eggs),trash fish (155±12 eggs) and formulated feed (110±10 eggs).The spawning rate was increased during September and October (water temperature,28.74±0.55℃) on average of 2.4 spawning per month; and low spawning rate was in January (water temperature,24.55±0.45℃) on average of 1 spawning per month.Among three light intensities (100,500,and 900 Ix) set to evaluate larval survival rate,larvae showed the highest survival rate (65.5％) at 900 Ix.The breeding method specifically in brackishwater developed in the present study is a new approach,will help the people from the regions of estuary and backwater to enhance their livelihood and it will lead to reduce the exploitation from the wild habitat.
Doropoulos, Christopher; Ward, Selina; Roff, George; González-Rivero, Manuel; Mumby, Peter J
Tropical reefs are dynamic ecosystems that host diverse coral assemblages with different life-history strategies. Here, we quantified how juvenile (coral demographics influenced benthic coral structure in reef flat and reef slope habitats on the southern Great Barrier Reef, Australia. Permanent plots and settlement tiles were monitored every six months for three years in each habitat. These environments exhibited profound differences: the reef slope was characterised by 95% less macroalgal cover, and twice the amount of available settlement substrata and rates of coral settlement than the reef flat. Consequently, post-settlement coral survival in the reef slope was substantially higher than that of the reef flat, and resulted in a rapid increase in coral cover from 7 to 31% in 2.5 years. In contrast, coral cover on the reef flat remained low (~10%), whereas macroalgal cover increased from 23 to 45%. A positive stock-recruitment relationship was found in brooding corals in both habitats; however, brooding corals were not directly responsible for the observed changes in coral cover. Rather, the rapid increase on the reef slope resulted from high abundances of broadcast spawning Acropora recruits. Incorporating our results into transition matrix models demonstrated that most corals escape mortality once they exceed 50 mm, but for smaller corals mortality in brooders was double those of spawners (i.e. acroporids and massive corals). For corals on the reef flat, sensitivity analysis demonstrated that growth and mortality of larger juveniles (21-50 mm) highly influenced population dynamics; whereas the recruitment, growth and mortality of smaller corals (recruitment in driving rapid increases in coral cover following large-scale perturbation in reef slope environments. PMID:26009892
Full Text Available Tropical reefs are dynamic ecosystems that host diverse coral assemblages with different life-history strategies. Here, we quantified how juvenile (<50 mm coral demographics influenced benthic coral structure in reef flat and reef slope habitats on the southern Great Barrier Reef, Australia. Permanent plots and settlement tiles were monitored every six months for three years in each habitat. These environments exhibited profound differences: the reef slope was characterised by 95% less macroalgal cover, and twice the amount of available settlement substrata and rates of coral settlement than the reef flat. Consequently, post-settlement coral survival in the reef slope was substantially higher than that of the reef flat, and resulted in a rapid increase in coral cover from 7 to 31% in 2.5 years. In contrast, coral cover on the reef flat remained low (~10%, whereas macroalgal cover increased from 23 to 45%. A positive stock-recruitment relationship was found in brooding corals in both habitats; however, brooding corals were not directly responsible for the observed changes in coral cover. Rather, the rapid increase on the reef slope resulted from high abundances of broadcast spawning Acropora recruits. Incorporating our results into transition matrix models demonstrated that most corals escape mortality once they exceed 50 mm, but for smaller corals mortality in brooders was double those of spawners (i.e. acroporids and massive corals. For corals on the reef flat, sensitivity analysis demonstrated that growth and mortality of larger juveniles (21-50 mm highly influenced population dynamics; whereas the recruitment, growth and mortality of smaller corals (<20 mm had the highest influence on reef slope population dynamics. Our results provide insight into the population dynamics and recovery trajectories in disparate reef habitats, and highlight the importance of acroporid recruitment in driving rapid increases in coral cover following large
Johnson, Nathan A.; Mcleod, John; Holcomb, Jordan; Rowe, Matthew T.; Williams, James D.
Accurate distribution data are critical to the development of conservation and management strategies for imperiled species, particularly for narrow endemics with life history traits that make them vulnerable to extinction. Medionidus walkeri is a rare freshwater mussel endemic to the Suwannee River Basin in southeastern North America. This species was rediscovered in 2012 after a 16-year hiatus between collections and is currently proposed for listing under the Endangered Species Act. Our study fills knowledge gaps regarding changes in distribution and early life history requirements of M. walkeri. Spatiotemporal changes in M. walkeri distribution were displayed using a conservation status assessment map incorporating metadata from 98 historical (1916–1999) and 401 recent (2000–2015) site surveys from museums and field notes representing records for 312 specimens. Recent surveys detected M. walkeri only in the middle Suwannee subbasin (n = 86, 22 locations) and lower Santa Fe subbasin (n = 2, 2 locations), and it appears the species may be extirpated from 67% of historically occupied 10-digit HUCs. In our laboratory experiments, M. walkeri successfully metamorphosed onPercina nigrofasciata (56.2% ± 8.9) and Etheostoma edwini (16.1% ± 7.9) but not on Trinectes maculatus, Lepomis marginatus, Notropis texanus, Noturus leptacanthus, Etheostoma fusiforme, orGambusia holbrooki. We characterize M. walkeri as a lure-displaying host fish specialist and a long-term brooder (bradytictic), gravid from fall to early summer of the following year. The early life history and distribution data presented here provide the baseline framework for listing decisions and future efforts to conserve and recover the species.
Full Text Available Problem statement: Because of dramatic declines in stocks of endangered Caspian brown trout males, Salmo trutta caspius in Caspian Sea, each male brooder is stripped indispensably more than once during the spawning season in other to artificial insemination in hatchery. The aim of the present study was to assay the changes of indicators of semen quality (sperm motility, sperm production, semen volume and chemical composition of seminal fluid during these sequential strippings. Approach: The 11 tagged males were stripped four times every 12-14 days with beginning of spermiation period (2 December 2008 towards its end (10 January 2008. One-way Analysis Of Variance (ANOVA was employed to analyze differences between means of semen parameters. Also, the relationships between semen parameters were tested using the bivariate correlation coefficients of Pearson. Results: The semen volume, sperm density, osmolality and the concentrations of Na+, Cl-, K+, Ca2+, Mg2+ and total protein gradually decreased whereas the values of glucose and triglyceride had no significant changes during sequential strippings. Also, the values of semen pH, the percentage (5s post-activation and duration of motility were statistically stable until third stripping but a decrease was recorded for these parameters in the fourth stripping. As well as, significant positive correlations were found for sperm density vs. K+, Cl-, Na+, Ca2+, Mg2+, total protein, spermatocrit; the percentage of motile spermatozoa Vs Ca2+, Mg2+, K+, Cl-, Na+, total protein and also the duration of motility Vs K+, Cl-, total protein and pH. Conclusion: The semen quality of Caspian brown trout males decrease in successive strippings during spawning season. Also, the knowledge on values and correlations between the sperm motility characteristics and the composition of seminal fluid could be useful to formulation of a species-specific extender solution for cryopreservation of semen of Caspian brown trout.
Pinzón, Jorge H C
Aim: Using high-resolution genetic markers on samples gathered from across their wide distributional range, we endeavoured to delimit species diversity in reef-building Pocillopora corals. They are common, ecologically important, and widespread throughout the Indo-Pacific, but their phenotypic plasticity in response to environmental conditions and their nearly featureless microskeletal structures confound taxonomic assignments and limit an understanding of their ecology and evolution. Location: Indo-Pacific, Red Sea, Arabian/Persian Gulf. Methods: Sequence analysis of nuclear ribosomal (internal transcribed spacer 2, ITS2) and mitochondrial (open reading frame) loci were combined with population genetic data (seven microsatellite loci) for Pocillopora samples collected throughout the Indo-Pacific, Red Sea and Arabian Gulf, in order to assess the evolutionary divergence, reproductive isolation, frequency of hybridization and geographical distributions of the genus. Results: Between five and eight genetically distinct lineages comparable to species were identified with minimal or no hybridization between them. Colony morphology was generally incongruent with genetics across the full range of sampling, and the total number of species is apparently consistent with lower estimates from competing morphologically based hypotheses (about seven or eight taxa). The most commonly occurring genetic lineages were widely distributed and exhibited high dispersal and gene flow, factors that have probably minimized allopatric speciation. Uniquely among scleractinian genera, this genus contains a monophyletic group of broadcast spawners that evolved recently from an ancestral brooder. Main conclusions: The delineation of species diversity guided by genetics fundamentally advances our understanding of Pocillopora geographical distributions, ecology and evolution. Because traditional diagnostic features of colony and branch morphology are proving to be of limited utility, the
Nozawa, Yoko; Huang, Yu-Sin; Hirose, Euichi
Sexual reproduction of the cyanobacteriosponge, Terpios hoshinota, was studied at Lyudao (Green Island), Taiwan, from 2011 to 2013 through histological examinations, electron microscopy, and in situ observations of larval release. Histological examinations identified five reproductive structures: oocytes, sperm cysts, cell masses, early-stage embryos, and mature embryos. These reproductive structures were often observed in the same specimens, indicating that T. hoshinota is a hermaphroditic brooder. No cyanobacteria were seen in the gametes, and transmission of symbiotic cyanobacteria from parental tissues to larvae likely occurred during embryogenesis. The cell mass, a loose aggregate of numerous symbiotic cyanobacteria and maternal sponge cells, appeared to be eventually incorporated and constitutes the inner part of pre-hatching larvae, suggesting that the larval type is pseudoblastula instead of parenchymella as previously suggested. A clear lunar periodicity was seen in the reproductive cycle; larvae were released mostly around the full moon and occasionally around the new moon. Reproductive activity declined during months with low temperatures (January-April). The larvae were characterized by negative buoyancy and limited mobility, suggesting a larval dispersal distance on a scale of meters under calm weather. However, long-distance dispersal of larvae could still be possible through occasional strong currents during bad weather, such as typhoons, if the larvae survived during the dispersal period by accessing extra energy from the symbiotic cyanobacteria through their photosynthates and/or consuming the cyanobacteria as a source of nutrients. This study showed that T. hoshinota has high fecundity, with a monthly release of numerous larvae over a long reproductive season. This high fecundity, along with local larval dispersal and rapid post-settlement growth, enables rapid population expansion of T. hoshinota.
Rajkumar, U; Vinoth, A; Shanmugam, M; Rajaravindra, K S; Rama Rao, S V
The present experiment was conducted to evaluate the Hsp-70, 27 and Ubiquitin mRNA expressions and serum T3 concentration in synthetic colored broiler female lines, Punjab Broiler-2 (PB-2), and Naked neck (NN) broiler chicken whose eggs were exposed to 2°C increased incubation temperature for 3 hours each on the 16th, 17 th, and 18th day of incubation. Another set of eggs were incubated at normal conditions that were utilized as the control. A total of 432 chicks, 216 from each breed (PB-2; NN) and treatment (Heat exposed: HE; normal: N), were randomly distributed and reared at high ambient temperatures (32°C-45°C) during the summer season in battery brooders. Birds were sacrificed at 0 and the 28th day post hatch and different tissues (heart, liver, muscle, spleen, and bursa) were collected to study Hsps and ubiquitin mRNA expression. There was no difference between the breeds and age of slaughter in Hsp-70 mRNA expression. The Hsp(70, 27, and ubiquitin) mRNA expression was significantly (P≤0.001) lower in HE birds than that of N birds in PB-2 chickens. Nonsignificant variation was observed in NN chicken. The Hsp-70 mRNA expression was highest in bursa and lowest in muscle and liver. Serum T3 concentration was similar in both HE and N birds. The study concludes that exposure to increased temperature during incubation results in reduced expressions of Hsp mRNA in almost all tissues indicating better thermotolerance of the HE birds. PMID:26158456
Full Text Available Deep-water gorgonian corals are long-lived organisms found worldwide off continental margins and seamounts, usually occurring at depths of ∼200-1,000 m. Most corals undergo sexual reproduction by releasing a planktonic larval stage that disperses; however, recruitment rates and the environmental and biological factors influencing recruitment in deep-sea species are poorly known. Here, we present results from a 4-year field experiment conducted in the Gulf of Maine (northwest Atlantic at depths >650 m that document recruitment for 2 species of deep-water gorgonian corals, Primnoa resedaeformis and Paragorgia arborea. The abundance of P. resedaeformis recruits was high, and influenced by the structural complexity of the recipient habitat, but very few recruits of P. arborea were found. We suggest that divergent reproductive modes (P. resedaeformis as a broadcast spawner and P. arborea as a brooder may explain this pattern. Despite the high recruitment of P. resedaeformis, severe mortality early on in the benthic stage of this species may limit the abundance of adult colonies. Most recruits of this species (∼80% were at the primary polyp stage, and less than 1% of recruits were at stage of 4 polyps or more. We propose that biological disturbance, possibly by the presence of suspension-feeding brittle stars, and limited food supply in the deep sea may cause this mortality. Our findings reinforce the vulnerability of these corals to anthropogenic disturbances, such as trawling with mobile gear, and the importance of incorporating knowledge on processes during the early life history stages in conservation decisions.
Lacharité, Myriam; Metaxas, Anna
Deep-water gorgonian corals are long-lived organisms found worldwide off continental margins and seamounts, usually occurring at depths of ∼200-1,000 m. Most corals undergo sexual reproduction by releasing a planktonic larval stage that disperses; however, recruitment rates and the environmental and biological factors influencing recruitment in deep-sea species are poorly known. Here, we present results from a 4-year field experiment conducted in the Gulf of Maine (northwest Atlantic) at depths >650 m that document recruitment for 2 species of deep-water gorgonian corals, Primnoa resedaeformis and Paragorgia arborea. The abundance of P. resedaeformis recruits was high, and influenced by the structural complexity of the recipient habitat, but very few recruits of P. arborea were found. We suggest that divergent reproductive modes (P. resedaeformis as a broadcast spawner and P. arborea as a brooder) may explain this pattern. Despite the high recruitment of P. resedaeformis, severe mortality early on in the benthic stage of this species may limit the abundance of adult colonies. Most recruits of this species (∼80%) were at the primary polyp stage, and less than 1% of recruits were at stage of 4 polyps or more. We propose that biological disturbance, possibly by the presence of suspension-feeding brittle stars, and limited food supply in the deep sea may cause this mortality. Our findings reinforce the vulnerability of these corals to anthropogenic disturbances, such as trawling with mobile gear, and the importance of incorporating knowledge on processes during the early life history stages in conservation decisions. PMID:23762358
Huff, G R; Huff, W E; Rath, N C; Tellez, G
The development of antibiotic-resistant bacteria has led to a need for alternatives to antibiotics for growth promotion and disease prevention in poultry production. The helical polysaccharide beta-1,3/1,6-glucan is derived from the cell wall of Saccharomyces cervisiae and has immunomodulating activities. The objective of this study was to determine the ability of 2 supplementation programs with a commercial beta-1,3/1,6-glucan product to protect broiler chicks from experimental respiratory challenge with Escherichia coli. Chicks were housed in battery-brooders from 1 d of age and fed a standard starter diet or the same diet containing 20 g/ton (22 ppm) of purified beta-1,3/1,6-glucan either continuously (BG25d) or for only the first 7 d prior to challenge (BG7d). At d 7 one-half of the birds were inoculated in the thoracic air sac with 800 cfu of a serotype O2, nonmotile strain of E. coli. All surviving birds were necropsied at d 25. Body weight of survivors and feed conversion efficiency were protected from the adverse effects of E. coli challenge by BG7d but not by BG25d. Mortality was nominally decreased from 63% (control) to 53% in BG25d and 47% in BG7d, but these decreases were not significant. The relative weights of the liver and heart were increased, and the bursa of Fabricius relative weights were decreased by E. coli challenge, and these effects were modulated by beta-glucan treatment. Despite positive effects of BG7d in E. coli-challenged birds, the BW of nonchallenged birds was decreased by BG7d and BG25d. These results suggest that supplementation of broiler diets with beta-1,3/1,6-glucan may be valuable for decreasing production losses due to E. coli respiratory disease, but that the immune stimulation provided may also result in decreased production values under experimental battery conditions or for birds raised in an environment with minimal disease challenges. PMID:16615344
Sahul Hameed, A S; Bonami, Jean-Robert
Macrobrachium rosenbergii is the most important cultured freshwater prawn in the world and it is now farmed on a large scale in many countries. Generally, freshwater prawn is considered to be tolerant to diseases but a disease of viral origin is responsible for severe mortalities in larval, post-larval and juvenile stages of prawn. This viral infection namely white tail disease (WTD) was reported in the island of Guadeloupe in 1995 and later in Martinique (FrenchWest Indies) in Taiwan, the People's Republic of China, India, Thailand, Australia and Malaysia. Two viruses, Macrobrachium rosenbergii nodavirus (MrNV) and extra small virus-like particle (XSV) have been identified as causative agents of WTD. MrNV is a small icosahedral non-enveloped particle, 26-27 nm in diameter, identified in the cytoplasm of connective cells. XSV is also an icosahedral virus and 15 nm in diameter. Clinical signs observed in the infected animals include lethargy, opaqueness of the abdominal muscle, degeneration of the telson and uropods, and up to 100 % within 4 days. The available diagnostic methods to detect WTD include RT-PCR, dot-blot hybridization, in situ hybridization and ELISA. In experimental infection, these viruses caused 100 % mortality in post-larvae but failed to cause mortality in adult prawns. The reported hosts for these viruses include marine shrimp, Artemia and aquatic insects. Experiments were carried out to determine the possibility of vertical transmission of MrNV and XSV in M. rosenbergii. The results indicate that WTD may be transferred from infected brooders to their offspring during spawning. Replication of MrNV and XSV was investigated in apparently healthy C6/36 Aedes albopictus and SSN-1 cell lines. The results revealed that C6/36 and SSN-1cells were susceptible to these viruses. No work has been carried out on control and prevention of WTD and dsRNA against protein B2 produced RNAi that was able to functionally prevent and reduce mortality in WTD
Full Text Available Early life history stages of marine organisms are generally thought to be more sensitive to environmental stress than adults. Although most marine invertebrates are broadcast spawners, some species are brooders and/or protect their embryos in egg or capsules. Brooding and encapsulation strategies are typically assumed to confer greater safety and protection to embryos, although little is known about the physico-chemical conditions within egg capsules. In the context of ocean acidification, the protective role of encapsulation remains to be investigated. To address this issue, we conducted experiments on the gastropod Crepidula fornicata. This species broods its embryos within capsules located under the female and veliger larvae are released directly into the water column. C. fornicata adults were reared at the current level of CO2 partial pressure (pCO2 (390 μatm and at elevated levels (750 and 1400 μatm before and after fertilization and until larval release, such that larval development occurred entirely at a given pCO2. The pCO2 effects on shell morphology, the frequency of abnormalities and mineralization level were investigated on released larvae. Shell length decreased by 6% and shell surface area by 11% at elevated pCO2 (1400 μatm. The percentage of abnormalities was 1.5- to 4-fold higher at 750 μatm and 1400 μatm pCO2, respectively, than at 390 μatm. The intensity of birefringence, used as a proxy for the mineralization level of the larval shell, also decreased with increasing pCO2. These negative results are likely explained by increased intracapsular acidosis due to elevated pCO2 in extracapsular seawater. The encapsulation of C. fornicata embryos did not protect them against the deleterious effects of a predicted pCO2 increase. Nevertheless, C. fornicata larvae seemed less affected than other mollusk species. Further studies are needed to identify the critical points of the life cycle in this species in light of future ocean
Aspectos reproductivos del acocil Cambarellus (Cambarellus montezumae (Crustacea: Decápoda: Cambaridae en condiciones controladas Breeding aspects of the crayfish Cambarellus (Cambarellus montezumae (Crustacea: Decapoda: Cambaridae under controlled conditions
José Luis Arredondo-Figueroa
Full Text Available El acocil Cambarellus (C. montezumae es una especie endémica cuya distribución está restringida a algunos cuerpos de agua lacustre. Se presentan los resultados sobre aspectos reproductivos de esta especie en condiciones controladas, con el objetivo de determinar la factibilidad de la producción de huevos y juveniles y su potencial aplicación a programas de rescate, repoblación y cultivo. Se realizaron 2 ensayos experimentales, el primero en 4 estanques exteriores de 800 litros conectados a sistemas cerrados de recirculación (SCR y el segundo en recipientes de plástico en laboratorio (RPL, de 2 litros. Para el primer ensayo, se manejaron 219 reproductores durante 335 días, obteniendo 136 hembras ovígeras. Cada hembra produjo en promedio 45 ± 23 huevos por puesta. El 83.7% de los huevos eclosionaron, obteniéndose un total de 3 162 juveniles. En los RPL se manejó una población F1 obtenida a partir de los reproductores del SCR en una relación 1 hembra: 2 machos, con 10 repeticiones. La producción de huevo fue variable con un promedio de 34 por hembra. Los indicadores de desempeño mostraron diferencias significativas (P ≤ 0.05 entre sexos con respecto a 6 de ellos. Los resultados indican la factibilidad para su cultivo y producción de huevos y juveniles.Cambarellus (C. montezumae is an endemic crayfish from Mexico, which actual distribution is restricted to few lacustrine bodies of water. Here we present results on the reproduction of this species under controlled conditions with the aim to determine the feasibility of the production of eggs and juveniles, as an strategy for their rescue, re-population and culture. Two experimental assays were conducted, the first one, in 4 outdoor 800-L tanks recirculation aquaculture systems (RAS and the second, in 2-L plastic containers under laboratory conditions (PCL. For the first assay, 219 brooders were used during 335 days , obtaining 136 ovigerous females. Each female produced an average
Rao, S V Rama; Prakash, B; Raju, M V L N; Panda, A K; Kumari, R K; Reddy, E Pradeep Kumar
Two experiments were conducted to study the effect of supplementing organic forms of zinc (Zn), selenium (Se) and chromium (Cr) on performance, anti-oxidant activities and immune responses in broiler chickens from 1 to 21 days of age, which were reared in cyclic heat-stressed condition under tropical summer in open-sided poultry house. A total of 200 (experiment I) and 450-day-old (experiment II) broiler male chicks (Cobb 400) were randomly distributed in stainless steel battery brooders (610 mm × 762 mm × 475 mm) at the rate of five birds per pen. A maize-soybean meal-based control diet (CD) containing recommended (Vencobb 400, Broiler Management Guide) concentrations of inorganic trace minerals and other nutrients was prepared. The CD was supplemented individually with organic form of selenium (Se, 0.30 mg/kg), chromium (Cr, 2 mg/kg) and zinc (Zn, 40 mg/kg) in experiment I. In experiment II, two concentrations of each Zn (20 and 40 mg/kg), Se (0.15 and 0.30 mg/kg) and Cr (1 and 2 mg/kg) were supplemented to the basal diet in 2 × 2 × 2 factorial design. A group without supplementing inorganic trace minerals was maintained as control group in both experiments. Each diet was allotted randomly to ten replicates in both experiments and fed ad libitum from 1 to 21 days of age. At 19th day of age, blood samples were collected for estimation of anti-oxidant and immune responses. Supplementation of Se, Cr and Zn increased (P 0.05) by the interaction between levels of Zn, Se and Cr in broiler diet. The FE improved (P 0.05) the immune responses (Newcastle disease titre and cell-mediated immune response to phytohaemagglutinin-P) in both the experiments. Based on the results, it is concluded that supplementation of organic form of Se, Cr and Zn (0.30, 2 and 40 mg/kg, respectively) either alone or in combination significantly improved performance and anti-oxidant responses (reduced LP and increased superoxide dismutase) in commercial
Máca, Ondřej; Pavlásek, Ivan
From July to November 2012, preliminary coprological examinations were carried out on 85 pooled faecal samples of different aged ring-necked pheasants (Phasianus colchicus) (hatches from May until July) from an intensive artificial breeding programme in the Czech Republic. Cryptosporidium oocysts were detected in 12 samples (14.1 %) of ages >12 weeks (August-September). These results were supported by findings of Cryptosporidium baileyi and Cryptosporidium meleagridis oocysts in intestinal, or cloacal contents, and/or the bursa of Fabricius in 9 from 36 examined dead pheasants (prevalence 25 %). We describe in detail the various age groups of pheasants after hatching and present graphically the overall results of coprological examinations, showing pathways of infection of C. baileyi and C. meleagridis during the full rearing seasons of 2013 and 2014. We found very similar mean proportions of Cryptosporidium-positive samples over the entire 2013 period in pheasantry (173 pooled samples tested, 25 positive, 14.5 %) and 2014 (238 samples tested, 43 positive, 18.1 %). All tests were verified as being Cryptosporidium positive in 9 from 219 (prevalence 4.1 %) and 4 from 168 (prevalence 2.4 %) post-mortem examinations. Significantly, C. baileyi was found more frequently in faeces, with positivities ranging from 11.1 to 100 % (4->16-week-old pheasants). Oocysts of C. meleagridis were detected at ages 6->15 weeks ranging from 7.1 to 100 % in faeces during the rearing seasons. The burdens of C. baileyi (7 of 14 and 10 of 16) and C. meleagridis (5 of 14 and 7 of 16) for each year, in monitored brooder houses, flight pens and spread across all open areas were recorded. Oocysts of C. baileyi and C. meleagridis obtained from this study, and Cryptosporidium galli (obtained in another aviary from 36-week-old pheasants), were sequenced, and we characterized the highly variable 60-kDa glycoprotein gene of C. meleagridis. These results highlight the real risk of
Full Text Available Broiler introduction and adaptation trial was done at Bahir Dar city in the year 2011/2012. The major objective of the trial was to introduce broiler breeds in to the region and evaluate their performance at smallholder level. A total of 1100 day old chicks of Hubbard Classical breed were purchased from Debre Zeit Agricultural Research Center and transported to Bahir Dar. Each participant received, on average, 109 day old chicks and 400kg started and finisher feed. Brooding was done using electrical brooder. Finished broilers were sold live and in processed form after six weeks of age. The average weight old day old chicks was 45.5g. The average weight of birds at end of 1st, 2nd, 3rd, 4th, 5th and 6th weeks were 136g, 364g, 711g, 1174g, 1665g and 2092g, respectively. The average final weight was 2092g (ranged 1957g - 2216g. The average cumulative mortality was 4.8% (Ranged 1.9%-6.5%. The average daily feed intake and cumulative feed intake of each bird during the entire period was 99g and 4052g, respectively. The average FCR was 1.84. The partial budget analysis result indicated that broiler production was profitable with a net benefit of 10.75 Eth Birr/head and 19.3 Ethi0pian Birr/kg, respectively. The result showed that participants who sold processed broiler meat fetched 8.6 Eth Birr/kg more than those participants who sold live birds. The survey result indicated that all participants were highly satisfied by the breed. According to the producers; the breed has paramount merit than other chicken breeds like; very fast growth, high meat production and short rearing period. The higher final body weight, the lower mortality, higher profitability and higher market demand revealed that broilers could be reared at small holder level in big cities like Bahir Dar. The result of the trial showed that actions should be taken to solve the prevailing constraint including; lack of day old chicks and quality feed. One of the main lessons we learned from
Full Text Available The sexual maturity of female Siamese gourami, Trichogaster pectoralis was studied by determining fecundity and gonadosomatic index (GSI. It was found that the size at sexual maturity of female Siamese gourami was 18.07±1.10 cm (mean±SD in average total length and 94.20±13.39 g in average body weight. The fecundity was 26,261±5,215.81 ova/fish and gonadosomatic index (GSI was 10.9±2.1%.Newly hatched larvae of Siamese gourami were produced by induced spawning using chemical injection (Suprefact and Motilium. The sexually mature fishes were cultured in fiber-glass tank (water volume 300 liters with the ratio of male and female brooders 1:1. The fertilization rate, hatching out and hatching rate experiments were carried out using a 15-liter aquarium (water volume 10 liters containing 1,000 eggs. It was found that the eggs were floating and rounded. The fertilized eggs had a diameter of 908.25±39.13 μm. The average fertilization rate was 91.12%, hatching out was 22 hr 10 min and average hatching rate was 83.03% at a water temperature of 27.0-30.5ºC. Sampling of the newly-hatched larvae was done at 2-hour intervals, when 20 of them were randomly taken and preserved in 10% buffered formalin for later analysis to determine the time of final yolk absorption. Observation using a microscope revealed that newly hatched larvae were 2.73±0.02 mm in total length and had yolk sacs of 153.76±2.49 μm3 in volume. The yolk sacs were completely absorbed within 110 hr after hatching at a water temperature of 27.0-30.5ºC. Up until full mouth development (start of feeding, 2-hourly samplings of twenty newly hatched larvae were taken from an aquarium for observation of the size of mouth opening. All the larvae had open mouths about 60 hr after hatching (3.56±0.04 mm TL, with the mouths measuring 443.64±24.26 μm in height.The feeding experiments were carried out using a 15-liter glass aquarium (water volume 10 liters containing 1,000 larvae aged 1.5 days
Full Text Available The sexual maturity of female snake head fish, Channa striatus was studied by determining fecundity and gonadosomaticindex (GSI. It was found that the size at sexual maturity of female snake head fish was 26.45±3.07 cm (mean ± SD,n=10 in total length and 167.4±48.09 g in body weight. The eggs were floating and rounded. The fertilized eggs had a diameterof 588±20.43 m. The fecundity was 10,279.1±2,527.9 ova/fish and gonadosomatic index (GSI was 5.07±1.04 %.Newly hatched larvae of snake head fish were produced by induced spawning using chemical injection (Suprefactand Motilium. The sexually mature fishes were cultured in a fiber-glass tank (water volume 300 liters with the ratio of maleand female brooders 1:1. The fertilization rate, hatching out and hatching rate experiments were carried out using 3 15-literglass aquaria (water volume 10 liters each containing 1,000 eggs. It was found that the average fertilization rate was 76.50%,hatching out occurred of 28 hr 40 min and average hatching rate was 60.26 % at a water temperature of 26.5-29.0°C. Samplingof the newly-hatched larvae was done at 2-hour intervals, when 20 of them were randomly taken and preserved in 10%buffered formalin for later determination of yolk absorption time. Observation using a microscope revealed that newlyhatched larvae were 3.18±0.11 mm in total length and had yolk sacs of 1,279.71±196.10 m3 in volume. The yolk sacs werecompletely absorbed within 80 hr after hatching at a water temperature of 26.5-29.0°C. Up until full mouth development (startof feeding, 2-hourly samplings of twenty newly hatched larvae were taken from an aquarium for observation of the size ofmouth opening. All the larvae had open mouths about 52 hr after hatching (5.48±0.16 mm TL, and measured 324.30±144.60m in mouth opening.The feeding experiments were carried out using a 15-liter glass aquarium (water volume 10 liters containing 1,000larvae aged 1.5 days post-hatching (just before
Cabral-Tena, Rafael A.; Sánchez, Alberto; Reyes-Bonilla, Héctor; Ruvalcaba-Díaz, Angel H.; Balart, Eduardo F.
Coral δ18O variations are used as a proxy for changes in sea surface temperature (SST) and seawater isotope composition. Skeletal δ13C of coral is frequently used as a proxy for solar radiation because most of its variability is controlled by an interrelationship between three processes: photosynthesis, respiration, and feeding. Coral growth rate is known to influence the δ18O and δ13C isotope record to a lesser extent than environmental variables. Recent published data show differences in growth parameters between female and male coral in the gonochoric brooding coral Porites panamensis; thus, skeletal δ18O and δ13C are hypothesized to be different in each sex. To test this, this study describes changes in the skeletal δ18O and δ13C record of four female and six male Porites panamensis coral collected in Bahía de La Paz, Mexico, whose growth bands spanned 12 years. The isotopic data were compared to SST, precipitation, photosynthetically active radiation (PAR), chlorophyll a, and skeletal growth parameters. Porites panamensis is a known gonochoric brooder whose growth parameters are different in females and males. Splitting the data by sexes explained 81 and 93 % of the differences of δ18O, and of δ13C, respectively, in the isotope record between colonies. Both isotope records were different between sexes. δ18O was higher in female colonies than in male colonies, with a 0.31 ‰ difference; δ13C was lower in female colonies, with a 0.28 ‰ difference. A difference in the skeletal δ18O could introduce an error in SST estimates of ≈ 1.0 to ≈ 2.6 °C. The δ18O records showed a seasonal pattern that corresponded to SST, with low correlation coefficients (-0.45, -0.32), and gentle slopes (0.09, 0.10 ‰ °C-1) of the δ18O-SST relation. Seasonal variation in coral δ18O represents only 52.37 and 35.66 % of the SST cycle; 29.72 and 38.53 % can be attributed to δ18O variability in seawater. δ13C data did not correlate with any of the environmental
Asociación del color de la concha de reproductores de Argopecten purpuratus (Lamarck, 1819 con la supervivencia, crecimiento y desarrollo larval de sus progenies Association between shell color of breeds (Lamarck, 1819 and the survival, growth and larval development of their progenies
Ricardo M García
most frequent shell colors. Knowing that Argopecten purpuratus shell color variation is under genetic control, in this work we test the hypothesis that loci that control shell color variation also affect larvae's growth rate, survival and/or development rate. Survival, growth and development rates were estimated in larvae produced in different crosses between brooders of A. purpuratus having low frequency shell colors (white or orange and "normal" (brown color. Results showed no significant differences in growth rates between larvae produced by crosses that involved brown shell parents, or orange by white parents. However, progenies of self fertilized orange and white parents showed significant differences in growth among them, and a lower growth rate than the remaining crosses. Results suggest that genes that control shell color variation in juvenile and adult A. purpuratus could affect the growth rates of their larvae, but not the development rate or survival.
Full Text Available The sexual maturity of female climbing perch, Anabas testudineus was studied by determining fecundity and gonadosomatic index (GSI. It was found that the size at sexual maturity of female climbing perch was 15.20±1.24 cm (mean±SD in total length and 61.10±17.32 g in body weight. The eggs were floating and rounded. The fertilized eggs had a diameter of 830±39 μm. The fecundity was 24,120.5±3,328.24 ova/ fish and gonadosomatic index (GSI was 10.4±2.5%. Newly hatched larvae of climbing perch were produced by induced spawning using chemical injection (Suprefact and Motilium. The sexually mature fishes were cultured in fiber-glass tank (water volume 300 liters with the ratio of male and female brooders 2:1. The fertilization rate, hatching out and hatching rate experiments were carried out using a 15-liter glass aquarium (water volume 10 liters containing 7,000-9,000 eggs. It was found that the eggs were floating and rounded. The fertilized eggs had a diameter of 830±39 μm. The average fertilization rate was 92.67%, hatching out was 20 hr 30 min and average hatching rate was 87.44% at a water temperature of 27.0-30.5ºC. Sampling of the newly-hatched larvae was done at 2-hour intervals, when 20 of them were randomly taken and preserved in 10% buffered formalin for later deter-mination of yolk absorption time. Observation using a microscope revealed that newly hatched larvae were 2.02±0.20 mm in total length and had yolk sacs of 111.33±46.19 mm3 in volume. The yolk sacs were completely absorbed within 92 hr after hatching at a water temperature of 27.0-30.5ºC. Up until full mouth development (start of feeding, 2-hourly samplings of twenty newly hatched larvae were taken from an aquarium for observation of the size of mouth opening. All the larvae had open mouths about 28 hr after hatching (2.95±0.59 mm TL, with the mouths measuring 328.42±32.23 mm in height. The feeding experiments were carried out using a 15-liter glass aquarium (water
Graybill, H W; Smith, T
other agencies. Whether Heterakis papillosa is the only, or at any rate, the chief accessory agent or whether there are others, living or inert, which when ingested by the turkey assist in preparing the way for the destructive invasion of the walls of the ceca and the liver by Amoeba meleagridis is a question now open to solution by experimentation. The relation of common poultry to outbreaks of blackhead may be accounted for, at least in part, by the fact that they are hosts of Heterakis papillosa. How frequently they also carry Amoeba meleagridis remains to be determined. Since earlier communications have contained certain practical suggestions on the rearing of turkeys and the prevention of blackhead, it is not out of place here to point out that the additional information presented in this article simply emphasizes the suggestions already made. Turkeys should be raised in the incubator and brooder and kept away from older turkeys and poultry. The shelters should be moved from time to time to prevent a too concentrated infection of the soil with Heterakis ova. Inasmuch as the factors producing blackhead may be deposited by certain still undetermined birds on the wing, disease may be looked for at any time during the warm season. It is not, however, very readily transmitted, and in the experiments described elsewhere the mortality from spontaneous blackhead was low. The flock should be looked over as frequently as possible, and whenever a turkey begins to droop, it should be isolated and killed if the drooping continues over several days. If such turkeys are allowed to recover, they should not be returned to the young flock but kept with older, presumably infected birds. Such birds are entirely satisfactory as a source of eggs, since there is no evidence that the latter transmit the infection. PMID:19868419
Kleiber, M; Dougherty, J E
1. An optimum of environmental temperature is to be expected for the utilization of food energy in warm blooded animals if their food intake is determined by their appetite. 2. Baby chicks were kept in groups of five chicks in a climatic cabinet at environmental temperatures of 21 degrees , 27 degrees , 32 degrees , 38 degrees , and 40 degrees C. during the period of 6 to 15 days of age. The intake of qualitatively complete food was determined by their appetite. Food intake, excretion, and respiratory exchange were measured. Control chicks from the same hatch as the experimental groups were raised in a brooder and were given the same food as the experimental chicks. The basal metabolism of each experimental group was determined from 24 to 36 hours without food at the age of 16 days. 3. The daily rate of growth increased with decreasing environmental temperature from 2.74 gm. at 40 degrees C. to 4.88 gm. at 21 degrees C. This was 4.2 to 6.5 per cent of their body weight. 4. The amount of food consumed increased in proportion to the decrease in temperature. 5. The availability of the food, used for birds instead of the digestibility and defined as See PDF for Structure showed an optimum at 38 degrees C. 6. The CO(2) production increased from 2.95 liters CO(2) per day per chick at 40 degrees C. to 6.25 liters at 21 degrees C. Per unit of the 3/4 power of the body weight, 23.0 liters CO(2) per kilo(3/4) was produced at 40 degrees C. and 43.4 liters per kilo(3/4) at 21 degrees C. The CO(2) production per unit of 3/4 power of the weight increased at an average rate of approximately 1 per cent per day increase in age. The R.Q. was, on the average, 1.04 during the day and 0.92 during the night. 7. The net energy is calculated on the basis of C and N balances. A maximum of 11.8 Cal. net energy per chick per day was found at 32 degrees C. At 21 degrees C. only 6.9 Cal. net per day per chick was produced and at 40 degrees C. an average of 6.7 Cal. 8. The composition of the