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131.
The objectives of this study were to examine the structural and metabolic integrity of isolated sheep external intercostal muscle bundles following variable lengths of preincubation (0 to 192 h). Samples of intact external intercostal muscle (10 to 15 g), with tendons attached, were prepared from growing wethers and maintained at their resting lengths during preincubation for 0 to 192 h. Protein synthesis (PS), protein degradation (PD), acetate oxidation and ultrastructural integrity of muscle samples were examined at 0 to 192 h, 0 to 96 h, 0 to 48 h and 0 to 96 h following isolation, respectively. Additionally, the effects of variable fetal calf serum (FCS) concentrations (0 to 20%; w/v) on PS and PD and acetate oxidation were examined. Rate of PS increased as preincubation time increased to 192 h; however, most of this increase was due to the proliferation of fibroblasts on the surface of the muscle sample. Addition of cytosine arabinoside to the incubation media prevented the fibroblast-dependent increase in PS; however, it did not entirely prevent the preincubation time-dependent increase in PS. Rate of PD increased greatly upon preincubation. The nitrogen balance of incubated muscles was negative at all times examined. Acetate oxidation was maintained through 12 h of preincubation and thereafter declined. Relatively normal myofibrillar structure was maintained through 48 h of preincubation; however, loss of mitochondrial integrity and dissolution of Z-disks at 48 h and at 96 h of preincubation were evident. Isolated tissues were able to respond to FCS concentration in medium following 48 h of preincubation.  相似文献   
132.
本文采用典型调查法 ,就小尾寒羊在豫西地区的饲养方式及农户适度饲养规模进行了评定。结果表明 ,在海拔 40 0 m以下的丘陵地区或牧坡陡峭的山区宜采用舍饲 ,在丘陵和浅山区宜采用半舍饲的饲养方式。根据对比分析 ,豫西地区农户小尾寒羊的最佳饲养规模为每个劳动力可平均饲养成年母羊 4~ 6只 ,其年末最佳存栏量为 2~ 3只成年母羊  相似文献   
133.
One-day-old Taiwan native male chicks were fed with maize-soybean rearing diets without supplemental vitamin E to 23 weeks of age. From 23 to 52 weeks of age, the cockerels (n = 90) were assigned at random to 5 dietary treatments and fed with maize-soybean diets supplemented with 0, 20, 40, 80 and 160 mg/kg of vitamin E (dl-alpha-tocopherol acetate). Pullets (225) of the same age were fed with standard diets throughout. They were artificially inseminated with one dose of 0.04 ml/bird intact and 5-fold diluted pooled semen at 31 to 43 weeks of age and at 49 weeks of age, respectively. The criteria evaluated included: semen quality, fertility and maximum and effective duration of fertility, blood characteristics, body and testes weight. Supplemental vitamin E did not affect cockerels' effective duration of fertility and percentage of fertility. However, when pullets were inseminated with diluted semen, supplementing 160 mg/kg vitamin E increased the maximum duration of fertility at 49 weeks of age. Cockerels receiving 40 to 160mg/kg supplements had higher sperm viability and motility after 39 weeks of age and those fed 80 mg/kg had higher sperm concentration at 39 weeks of age. Cockerels receiving supplements of more than 40 mg/kg vitamin E had higher body weight gain. Plasma cholesterol and testosterone were not affected by supplemental vitamin E. However, plasma luteinising hormone (LH) concentration was lower in cockerels fed 160 mg/kg. Lack of supplemental vitamin E over 39 weeks was associated with lower semen quality but did not reduce the proportion of fertile eggs laid by inseminated hens, perhaps because the insemination dose compensated for low sperm quality. We found that the maximum duration of fertility might be improved by supplementing 160 mg/kg vitamin E at 49 weeks of age.  相似文献   
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Rats were successfully infected with Japanese Fasciola sp. by transplantation of juvenile worms (JW) or metacercariae (MC) into the abdominal cavity. Moreover, the rat was investigated on its suitability for different experiments with liver flukes. JWs or MCs transplanted intraperitoneally (IP) matured in the bile duct of rats. Moreover, more stable infections were established by inoculation of JWs than MCs. About 3 of 10-15 JWs transplanted into the abdominal cavity of a rat matured and laid eggs in the bile duct. The mean prepatent period was 63.5 days in the JW inoculated group. EPG values were kept constant at a level of 10(2)-10(3) about 100 to 230 days after the transplantation of JWs. The life span of Japanese liver flukes was estimated to be about 400 days in rats. From these results, it was concluded that the rat is suitable for various experiments with Fasciola sp.  相似文献   
139.
Follicle growth, oocyte quality or oocyte growing environment (follicular fluid) were evaluated in cows with severe liver damage (haemorrhage, telangiectasis, cholangitis and abscess) that were visually diagnosed at the slaughterhouse. Holstein cows aged 40–90 months with either a healthy liver (HL cow) or damaged liver (DL cow) were selected as donors. Follicle development kinetics was evaluated by counting the follicles at various developmental stages. In addition, the biochemical characteristics of the follicular fluids, developmental competence of preantral follicles cultured for 16 days in vitro and the ability of oocytes to develop to the blastocyst stage 8 days after fertilization were examined. DL cows had fewer secondary follicles than HL cows, and the correlation between the number of secondary follicles and the number of primary follicles differed among DL and HL cows. The follicular fluid of DL cows contained significantly lower levels of albumin and a higher total protein content than that of HL cows. Oocyte nuclear maturation assessed at 5, 16 and 21 h after beginning of culture was slower in DL cows than in HL cows, although the final maturation rates did not differ. The rate of polyspermic fertilization was significantly higher and the proportion of cleavage at 48 h after insemination and blastulation lower in DL cows compared with HL cows. When preantral follicles were cultured in vitro, the rate of follicles with normal morphology was lower in DL cows than in HL cows. These findings suggest that the kinetics of folliculogenesis differ among DL and HL cows and the developmental ability of preantral follicles and oocytes is lower in DL cows than in HL cows.  相似文献   
140.
Background: Obese people with heart failure have improved survival compared with their normal or underweight counterparts. The purpose of this study was to determine if there is a relationship between body weight or body condition and survival in cats with heart failure. Hypothesis: Body weight and body condition score (BCS) are predictors of survival in cats with heart failure. Animals: One‐hundred and one cats with heart failure (International Small Animal Cardiac Health Council Classes II, IIIa, or IIIb) evaluated between March 2007 and June 2009. Methods: Data regarding initial body weight and BCS, subsequent changes in body weight, and treatment were collected from records and compared with survival times. Results: Median initial body weight was 5.1 kg (range, 2.2–9.5 kg). Median BCS was 5 (range, 3–9). Of the 68 cats that were discharged from the hospital, median body weight change was 0.0 kg (range, ?2.6 to +2.3 kg). Survival time for all 101 cats was 93 days (0–811 days). Survival could be predicted using a model combining initial body weight (P= .02), body weight squared (P= .02), and survival to discharge (P < .001) with a resulting global P value for this model of P < .0001. Conclusions and Clinical Importance: Cats with the lowest and highest body weights had reduced survival times compared with those with body weights in the intermediate ranges, suggesting a U‐shaped relationship between body weight and survival. Additional research into the effects of body composition could help to determine optimal management of cats with heart failure.  相似文献   
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