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71.
The prolificacy of the ewes was measured as the number of lambs born per ewe mated (NLB) when the ewes were 1–4 years of age. The ewe productivity related to the same age interval was measured by special ewe production indices (EPI). The genetic parameters for these traits were estimated by a series of bivariate REML analyses using animal models. The material used for the genetic analysis contained records on 193 213 ewes. The heritability estimates for NLB were h2 = 0.17, 0.13, 0.11, 0.10 for the four respective age classes. Corresponding estimates for EPI were h2 = 0.16, 0.17, 0.17, 0.15. The genetic correlations among NLB at different ages ranged from 0.63 to 0.98 and among EPI from 0.82 to 0.99. The genetic correlations between NLB and EPI were generally low. The material used for estimating the breeding values by the MT‐BLUP Animal Model consisted of 1.5 million individuals in the pedigree file. In total 815 782 ewes had records for the NLB and 763 491 ewes had production index (at least 1 year). The records were registered in the years 1990–2006. All possible missing patterns were present in the data. In the iteration process expected values for missing traits were generated and solutions were obtained on canonical transformed scale. The genetic evaluations were run independently for NLB and EPI for computational convenience given the correlations between these traits were negligible.  相似文献   
72.
Neoplasms in the perianal region are frequently diagnosed in dogs. The aetiology is unknown, and most of them are benign. In this study, 240 neoplasms of the perianal glands of dogs were retrieved from the Department of Pathology archives of the Faculty of Veterinary Medicine and Zootechny of University of São Paulo (FMVZ/USP), from 1984 to 2004. All 240 cases were re‐examined by two pathologists. Nine cases (4%) were diagnosed as hyperplasia, 49 (20%) as group I adenoma, 81 (34%) were classified as moderately differentiated adenomas of the group II, 46 (19%) were poorly differentiated adenomas of group II, 48 (20%) were carcinoma of the group III according to the classification proposed by Berrocal, and 7 (13%) were other kind of tumours. Males over 8 years of age were predominantly affected. Cell proliferation was quantified by counting proliferating cell nuclear antigen (PCNA) positive nuclei, and apoptosis was quantified by counting fluorescent eosin‐stained apoptotic corpuscles (AC) in normal tissue, hyperplasia and in different histologic types of neoplasia of these glands. A parallel pattern of increase in both parameters (cell proliferation and apoptosis) was obtained. The net growth index (NGI), represents how much a cell population is proliferating or dying and was achieved by dividing the mean PCNA count in 1000 cells by the mean AC stain count in 1000 cells. NGI was different between hyperplasia and neoplasia; group I adenomas have a much higher potential of growth, and NGI decreases from benign towards malignant lesions. These results show up the importance of studying cell proliferation and apoptosis to understand the carcinogenesis of dog perianal gland.  相似文献   
73.
Cataracts are among the most common ocular diseases, and are a leading cause of vision loss in humans and dogs. Jack Russell Terriers (JRT) and Labrador Retrievers (LR) are among the most popular canine breeds in the United Kingdom, and also among the most affected by cataracts.This study aimed to analyze the clinical features and the surgical outcome of cataracts in JRT and LR in an ophthalmologic reference Veterinary Hospital in the United Kingdom. For that purpose, medical records from JRT and LR diagnosed with cataracts between January 2015 and December 2016 were retrospectively evaluated. Data related to identification, clinical history, preoperative features, and surgical outcomes were analyzed.Forty-four dogs (81 eyes), including 26 JRT and 18 LR, were enrolled in the study. Mean ages were 10.2 ± 3.2 years in JRT and 8.5 ± 3.7 years in LR. Twenty-eight (63.6%) were females and 16 (36.4%) were males. Most dogs (84.1%) presented with bilateral cataracts. Nuclear and cortical cataracts were the most prevalent type in both breeds (JRT: n?=?30, 61.2%; LR: n?=?16, 50.0%), although subcapsular cataracts were also frequent in LR (n?=?10, 31.3%). Significant differences in cataract location within the lens were detected between the two breeds (P?=?.002).Senile in JRT (n?=?7) and genetic in LR (n?=?7) were the most common etiologies. Concomitant ocular lesions were more frequent in dogs presented with cataracts in advanced stages, and included lens (n?=?18; JRT: n?=?15; LR: n?=?3) and retinal alterations (n?=?8; JRT: n?=?2; LR: n?=?6), and glaucoma (n?=?6; JRT: n?=?5; LR: n?=?1). Thirty-three animals (75.0%, 51 eyes) were submitted to phacoemulsification with intraocular lens placement. Of these, 28 eyes (54.9%; JRT: n?=?21; LR: n?=?7) were visual, 19 eyes (37.3%; JRT: n?=?11; LR: n?=?8) presented impaired vision and four eyes (7.8%; JRT: n?=?0; LR: n?=?4) were blind at last clinical record. Postoperative complications were detected in 11 eyes (21.6%), and were more frequent in dogs presented with cataracts in advanced stages.These results and the multifactorial nature of cataracts call for further studies to identify and characterize the variables in a broader assessment, including other breeds and influencing factors.  相似文献   
74.
75.
This study investigated possible immunotoxic effects of Senna occidentalis (So) seeds incorporated in broiler chicken rations at different concentrations (0.0%, 0.25%, 0.50% and 0.75%), for 28 or 42 days. We evaluated innate immune function (macrophage activities of spreading, phagocytosis, peroxide and nitric oxide production) and acquired immune function (humoral and cellular immune responses), as well as lymphoid organ weights and pathology. There was enhanced macrophage activity, as hydrogen peroxide production increased (P < 0.05) in cells of birds given 0.75%So, but there were no other pro-inflammatory effects. Birds receiving 0.75% of So in ration for 42 days gained less weight (P < 0.01), and showed a decrease in relative weight of the bursa of Fabricius (P < 0.05) and spleen (P < 0.01). In addition, morphological changes were also noted in these lymphoid organs, with depletion of lymphoid cells on the spleen and bursa of Fabricius, resulting in lower relative weight of both lymphoid organs. No impairment of humoral immune response against Newcastle disease and in cellular immune response after a phytohaemagglutinin challenge was found. It is probable that mitochondrial damage and related apoptosis may be responsible for the enhanced peroxide production and the reduced relative weight of the bursa of Fabricius and spleen.  相似文献   
76.
The effects of a double replacement of fish oil (FO) and fish meal (FM) by dietary vegetable ingredients in juvenile gilthead sea bream (Sparus aurata L. 1758) on some indices of lipid metabolism and plasma insulin levels were analysed. Four experimental diets with a replacement of 75% of FM by plant proteins (PP) were administered. Added oil was either FO (75PP/FO diet), or a vegetable oil mix (VO), replacing 33%, 66% or 100% of FO (75PP/33VO, 75PP/66VO, 75PP/100VO diets). Another diet with 50% of substitution of FM by PP and with 100% of VO was also tested (50PP/100VO diet). Final body weight was similar in all diet groups, except for the 75PP/100VO group, which presented lower values. Circulating insulin levels increased with feed administration in all groups and no differences between diets were observed, with the exception of the 75PP/FO group, which presented higher plasma insulin values. In adipose tissue, glucose‐6‐phosphate dehydrogenase and malic enzyme activities decreased with the inclusion of vegetable oil, especially 5 h after feeding. Diet had no significant effect on the hepatic activity of either enzyme. Lipoprotein lipase activity decreased in white muscle and adipose tissue with the replacement of fish oil in 75PP diets, 5 h after feeding. In conclusion, the use of a combined replacement of fish oil and fish meal by vegetable ingredients in gilthead sea bream permits satisfactory growth, with moderate changes in tissue lipogenesis and lipid uptake.  相似文献   
77.
Fish are able to select a balanced diet according to their nutritional needs by choosing among incomplete feeds or even pure macronutrients. However, the relevance of both the organoleptic properties of diet and the postingestive signals that they produce remains unclear. Thus, sharpsnout seabream were allowed to select between diets containing different edible oils with their organoleptic properties masked by using gelatine capsules. Fish were fed capsules of two different colours so that they could associate the capsule colour with its corresponding postingestive effect. The longitudinal experiment included a first phase during which the fish were adapted to consuming the gelatine capsules. In a second phase, the fish were challenged with two different encapsulated diets: one comprising a complete diet containing fish oil and the other a fat‐free diet. Sharpsnout seabream showed a preference for the fish oil capsules (3.8 ± 1.1 g kg?1 body weight (BW), 66.8% of total intake) over the fat‐free capsules, showing that they were able to associate the colour of the capsule with their nutritional content through postingestive signals. After that, the fish were challenged to select between the capsules containing the fish oil diet and capsules containing a vegetable oil (linseed or soybean), in which case they showed no preference between diets (2.4 ± 0.3: 2.1 ± 0.5 g kg?1 BW of fish oil versus linseed oil capsules and 2.2 ± 0.2: 1.8 ± 0.6 g kg?1 BW of fish oil versus soybean oil capsules), indicating that the fatty acid composition of the different oils was not sufficient to affect dietary selection through postingestive signals. So, in conclusion, when orosensorial information from food is absent, the fish are able to select between diets at a macronutrient level by using postingestive information. However, this information is not sufficient for distinguishing between diets that differ in the type of oil used.  相似文献   
78.
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   
79.
Two trials were conducted to determine the efficacy of fish fed live yeast Debaryomyces hansenii strain CBS 8339 on immune and antioxidant systems in leopard grouper Mycteroperca rosacea infected with Aeromonas hydrophila. Juveniles (12±0.5 g) were fed with a control diet or a D. hansenii‐supplemented diet (106 colony‐forming units per gram) for 5 weeks. The live weight of fish was registered on a weekly basis. After 4 weeks, fish from each treatment were immunocompromised with pathogenic A. hydrophila and further fed for 1 week in order to evaluate the effect on immunological and antioxidant parameters. Generally, the results showed enhanced growth performance in fish fed the diet containing yeast compared with the control. Addition of live yeast had no significant effect on the immunological parameters after 4 weeks of feeding. However, post infection with A. hydrophila fish fed the yeast‐supplemented diet resulted in a significant increase in the levels of plasmatic immunoglobulin M. Superoxide dismutase and catalase (CAT) activities were significantly higher in the yeast group. In this fish, CAT and heat shock protein 70 genes were up‐regulated before and after infection of A. hydrophila. The present study is the first one reporting that yeast (D. hansenii) can enhance immunity and resistance against A. hydrophila.  相似文献   
80.
Abstract

This three-year study (2003–2005) aimed to improve the yield and quality of pastures growing naturally that are colonized by naturally occurring vegetation without agricultural input under hazelnut (Corylus sp.) orchards in the middle and eastern Black Sea regions of Turkey. There were eight treatments: 1) control; 2) fertilizer only (triple superphosphate 44% and calcium ammonium nitrate 26%) (80kg ha?1 P and 60 kg ha?1 N in Samsun; 100 kg ha?1 P and 80 kg ha?1 N in Ordu; 100 kg ha?1 P and 40 kg ha?1 N in Giresun); 3) lime only (calcium carbonate 94%) (3.0 t ha?1 lime in Samsun; 4.5 t ha?1 lime in Ordu and Giresun); 4) early cut only; 5) soil aeration only; 6) fertilizer+lime; 7) fertilizer+lime+early cut; 8) fertilizer+lime+soil aeration, laid out in a randomized complete block design with four replicates at each location. The highest dry matter (DM) yield of kg ha?1 and crude protein content (%) was obtained from the treatments that included fertilizer. There was no difference in DM production between any of the combination treatments that involved fertilizer and the fertilizer alone treatment. Only lime and aeration applications also increased yield compared to control, but not as much as did any treatment including fertilizer. Crude protein content of the pasture ranged from 13.3 to 18.1% across locations. Nitrogen and phosphorus fertilizer are recommended to improve DM yields and herbage quality for pastures under hazelnut orchards.  相似文献   
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