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171.
Martin Bonamy Sabrina Kluska Elisa Peripolli Marcos Vinícius Antunes de Lemos Sabrina Thaise Amorim Roberto Jose Vaca Raysildo Barbosa Lbo Letícia Mendes de Castro Carina Ubirajara de Faria Fabio Borba Ferrari Fernando Baldi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(1):15-22
The aim of this study was to estimate genetic parameters for different precocious calving criteria and their relationship with reproductive, growth, carcass and feed efficiency in Nellore cattle using the single‐step genomic BLUP. The reproductive traits used were probability of precocious calving (PPC) at 24 (PPC24), 26 (PPC26), 28 (PPC28) and 30 (PPC30) months of age, stayability (STAY) and scrotal circumference at 455 days of age (SC455). Growth traits such as weights at 240 (W240) and 455 (W455) days of age and adult weight (AW) were used. Rib eye area (REA), subcutaneous fat thickness (SFT), rump fat thickness (RFT) and residual feed intake (RFI) were included in the analyses. The estimation of genetic parameters was performed using a bi‐trait threshold model including genomic information in a single‐step approach. Heritability for PPC traits was moderate to high (0.29–0.56) with highest estimates for PPC24 (0.56) and PPC26 (0.50). Genetic correlation estimates between PPC and STAY weakened as a function of calving age. Correlation with SC455, growth and carcass traits were low (0.25–0.31; ?0.22 to 0.04; ?0.09 to 0.18, respectively), the same occurs with RFI (?0.09 to 0.08), this suggests independence between female sexual precocity and feed efficiency traits. The results of this study encourage the use of PPC traits in Nellore cattle because the selection for such trait would not have a negative impact on reproductive, growth, carcass and feed efficiency indicator traits. Stayability for sexual precocious heifers (PPC24 and PPC26) must be redefined to avoid incorrectly phenotype assignment. 相似文献
172.
Antibody phage display libraries are a useful tool in proteomic analyses. This study evaluated an antibody recombinant library for identification of sex-specific proteins on the sperm cell surface. The Griffin.1 library was used to produce phage antibodies capable of recognizing membrane proteins from Nelore sperm cells. After producing soluble monoclonal scFv, clones were screened on Simental sperm cells by flow cytometry and those that bound to 40–60% of cells were selected. These clones were re-analyzed using Nelore sperm cells and all clones bound to 40–60% of cells. Positive clones were submitted to a binding assay against male and female bovine leukocytes by flow cytometry and one clone preferentially bound to male cells. The results indicate that phage display antibodies are an alternative method for identification of molecules markers on sperm cells. 相似文献
173.
174.
Genetic structure of the Amur tiger (Panthera tigris altaica) population: Are tigers in Sikhote‐Alin and southwest Primorye truly isolated?
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Pavel A. SOROKIN Vyatcheslav V. ROZHNOV Anna U. KRASNENKO Victor S. LUKAREVSKIY Sergey V. NAIDENKO Jose A. HERNANDEZ‐BLANCO 《Integrative zoology》2016,11(1):25-32
We used molecular genetic analyses to noninvasively identify individual Amur tigers and define subpopulations of tigers in the Russian Far East. We identified 63 individuals after genotyping 256 feces, 7 hair and 11 blood samples collected within southern, central and northern Sikhote‐Alin, as well as Southwest Primorye. Analysis of nuclear DNA at 9 microsatellite loci demonstrated greater genetic similarity between animals from southern and northern Sikhote‐Alin (some 500 km apart) than between animals from Ussuriskii State Nature Reserve and Southwest Primorye (less than 10 km apart at their nearest point), suggesting that a true barrier exists preventing movements of tigers between Southwest Primorye and the southern Sikhote‐Alin Mountains. 相似文献
175.
Isolation of Escherichia fergusonii from the feces and internal organs of a goat with diarrhea
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Hariharan H López A Conboy G Coles M Muirhead T 《The Canadian veterinary journal. La revue veterinaire canadienne》2007,48(6):630-631
A fecal sample from a 42-year-old goat with a 2-month history of poor weight gain and diarrhea yielded a moderate growth of an organism resembling Salmonella spp. on MacConkey agar. The organism was identified as Escherichia fergusonii. The animal was euthanized. Samples of intestine, lung, liver, and kidney yielded the same organism, E. fergusonii. 相似文献
176.
Aurielle S. Medeiros Mércia V. F. dos Santos Márcio V. da Cunha Alexandre C. L. de Mello Djalma E. Simões Neto Osniel F. de Oliveira James P. Muir Jose C. B. Dubeux Jr André E. dos Santos 《Grass and Forage Science》2023,78(1):161-172
The use of legumes is an important strategy for animal feeding, especially during the dry season. The aim was to evaluate the effect of planting densities (40,000; 15,625 and 10,000 plants ha−1) and harvest heights (20 and 40 cm) on the morphology, accumulation and survival of Desmanthus (Desmanthus pernambucanus [L.] Thellung), cultivated in subhumid tropical region, as well as to estimate the repeatability of the evaluated characteristics and the optimal number of measurements. The treatments were randomized in blocks, with subdivided plots and four replicates. Planting densities were evaluated in the plots and the harvest heights in the subplots. Eight harvests were carried out with an interval of 84 days. Morphological and productive characteristics and survival were evaluated. Cultivation under density of 40,000 plants ha−1 produced taller plants, with higher leaf area index (LAI = 0.98), light interception (LI = 49%), individual accumulations (18.8 g DM plant−1) and by area (576.5 kg DM ha−1 harvest−1), although resulting in reduced plant stand (66%). Harvest heights do not affect accumulation and survival. It is possible to reduce the number of measurements for stem diameter, number of leaflets per leaf (R2 = 95%), plant height, canopy diameter, LAI, LI, leaf length and width, number of leaves per branch, branch diameter and LBR (R2 = 90%), optimizing resources for future research. Desmanthus has potential for use in protein banks, being harvested in the rainy season, conserved and supplied in addition to animals, but plant growth is minimal during the dry season under rainfed conditions. 相似文献
177.
Victor Manuel Ocaño‐Higuera Alfonso Nivardo Maeda‐Martínez María Elena Lugo‐Sánchez Gillermina García‐Sánchez Enrique Márquez‐Ríos Silvia Gómez‐Jimenez Ramón Pacheco‐Aguilar 《Aquaculture Research》2011,42(8):1087-1095
Currently, there is an increasing interest in shipping live adult scallops to markets and broodstock to hatcheries; nevertheless, information about the shipping effect on live scallops physiology is very scarce. In a previous study, a method in emersion was developed to ship scallop seed out of water, but it was not known whether this method is useful to transport adult organisms. As a consequence, the purpose of this study was to evaluate the effects of transportation by the emersion method on the physiological status of the adductor muscle of adult giant lion's paw scallop. Live specimens were packaged in a container and transported in emersion for 11 h. Six scallops were frozen in a farm and a similar number were frozen as soon as they arrived to the laboratory. Physiological indices were determined in each lot and the survival was estimated 24 h after re‐immersion. As a result of the transportation, a significant loss (P<0.05) of total carbohydrates, glycogen, adenosine 5′‐triphosphate and adenilated energetic charge, and a significant increase (P<0.05) in the free amino acids concentration were observed. Eighty‐eight per cent survival was achieved; therefore, we conclude that this method is appropriate for shipping live adult scallops of Nodipecten subnodosus. 相似文献
178.
Elva Mayra Toledo‐Cuevas Francisco J Moyano López Dariel Tovar Ramírez Carlos A Strüssmann Carlos Alfonso Álvarez‐González Carlos Cristian Martínez‐Chávez Carlos A Martínez‐Palacios 《Aquaculture Research》2011,42(6):776-786
The early development of the digestive biochemistry of three cultured Atherinopsids (two Odontesthes species and Chirostoma estor) was investigated. Relatively high lipolytic and high alkaline proteolytic activities were found in all species. In addition, gene expression of lipase and trypsin during the early development of C. estor not only indicates an early onset of the lipase activity but also demonstrates a major importance of protein digestion in this species. However, despite all of them share similar habitats, differences in their digestive activities were evident. The rise in the activities of brush border membrane enzymes correlated with the decrease in cytosolic activities, used as indicator of maturation of the digestive tract, was detected in both species of Odontesthes at 9 weeks after hatching. In contrast, no similar signs were measured in C. estor, this being in agreement to the long weaning period (nearly 5 months) reported for this species. 相似文献
179.
Cranial osteological development and abnormalities in northern palm ruff,Seriolella violacea (Guichenot, 1848), larvae and juveniles
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Milton Bohórquez‐Cruz Wilfrido Argüello‐Guevara Alfonso Silva 《Aquaculture Research》2017,48(2):624-632
Seriolella violacea, a new species to be potentially farmed in Chile and Peru, has shown cranial malformations during farming that could adversely affect its commercial development. This study seeks to generate early knowledge of the osteological development and type of cranial abnormalities that this species presents under culture conditions. Larvae from wild caught broodstock were reared from 1 to 60 days post hatching (DPH) (4.8 ± 0.1 mm TL and 11.8 ± 1.0 mm TL respectively). Larvae samples were collected throughout the experimental trial for recording cranial osteological development and abnormalities in cartilage and bone. At 5.7 ± 0.1 mm TL, coraco‐scapular, sclerotic, ethmoid plate and quadrate cartilages were present. At 8.0 ± 0.6 mm TL, early ossification was observed in the jaw, premaxilla and maxilla. At 11.8 ± 1.0 mm TL, the branchiostegal rays, jaw, maxilla and opercular complex were ossified. The first cartilaginous structures observed were the Meckel's cartilage, the branchial arches and the suspensory ligament. The first cranial malformations were detected at 5.7 ± 0.1 mm TL, coinciding with mouth opening. The most frequent malformations were a curvature of the lower jaw (23.1%), abnormal separation between branchial arches and the Meckel's cartilage (19.4%) and bulging jaws (15.7%). 相似文献
180.
Marcelino Herrera Ismael Hachero-Cruzado Catarina Oliveira José F. Ferrer José M. Márquez Montserrat Rosano Jose I. Navas 《Aquaculture International》2010,18(3):475-485
The weaning phase can be decisive in fish-culture viability. In this work, the relationship between the initial size and weaning
success has been studied in wedge sole (Dicologoglossa cuneata). For each age (30, 50, and 70 days after hatching, DAH), two to three sizes were selected, and all were put on the same
feeding schedule for 20 days. Each batch (three replicates) was sampled at 1, 10, and 20 days. Specific growth rate (SGR)
and survival were compared at the end of the co-feeding period, after 10 days on dry feed only. The best results for survival
and growth were found with the smallest larvae, and vice versa. The SGRs and survival rates recorded during the co-feeding
period were higher (0.8–15.6 day−1 and 68.3–97.8%) than those from the dry-food phase (0.9–4.7 day−1 and 56.3–66.7%). Successful weaning (survival = 65% and SGR = 9.3 day−1) is possible with 30 DAH larvae (7.6–8.1 mm and 3.9–4.6 mg). In conclusion, the most effective weaning would be possible
at 30 DAH, implying significant Artemia savings (25–50%). 相似文献