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41.
试验旨在研究菊苣酸对放牧牦牛围产期生长性能、血清生化指标及抗氧化能力的影响。选择体况良好、体重接近(195~205kg)的围产期牦牛16头,随机分为2组,每组8头,对照组饲喂精料补充料+燕麦青干草,试验组饲喂精料补充料+燕麦青干草+0.15kg/d菊苣酸。试验期60d(从产前30d到产后30d),于产前第15天、产前第7天、分娩当天、产后第7天、产后第15天采集血液,进行相应指标的测定。结果显示:在产后第15天,试验组牦牛血清尿素氮(BUN)显著低于对照组(P<0.05);在分娩当天和产后第7天,试验组牦牛血清葡萄糖(GLU)含量、碱性磷酸酶(ALP)活性及总抗氧化能力(T-AOC)显著高于对照组(P<0.05),谷草转氨酶(AST)活性显著低于对照组(P<0.05);在分娩当天,试验组牦牛血清谷胱甘肽过氧化物酶(GSH-Px)、超氧化物岐化酶(SOD)活性显著高于对照组(P<0.05),血清丙二醛(MDA)含量显著低于对照组(P<0.05)。综合试验结果,添加菊苣酸能有效缓解围产期放牧牦牛氧化应激状态,提高其抗氧化能力。 相似文献
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It has been found that fibroblast growth factor receptor (FGF-FGFR) signaling can regulate the expression of adipocyte differentiation genes. FGF9 is one of the members of FGFs that mainly binds receptors FGFR2 and FGFR3. FGF9 is highly expressed in the adipose tissue of humans and mice, but there are few reports on the role of FGF9 in goat intramuscular adipocyte differentiation. Therefore, this study explored the effect of FGF9 on adipocyte differentiation through cell culture, interference, and overexpression. The expression of receptors FGFR1–FGFR4 in adipocyte differentiation and their effects on differentiation were detected to screen receptor gene of FGF9. Finally, the interaction between FGF9 and the receptor was tested by cotransfection. Our results showed that FGF9 interacts with FGFR2 to inhibit goat intramuscular adipocyte differentiation by regulating peroxisome proliferator-activated receptor gamma (PPARγ) and preadipocyte factor 1 (Pref1), which is a data support for subsequent pathway research. 相似文献
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OBJECTIVE: To investigate the relationship between diet, growth rate and the presence of caudal cervical malformation in Doberman puppies. DESIGN: A prospective study of 15 Dobermann puppies from three unrelated litters, aged from 0 to 16 weeks. PROCEDURE: The growth rate in terms of body weight gain and increase in ulna length were measured weekly for all puppies. In addition the nutritional quality of the diets was assessed. Radiographs of the cervical spine were taken at 6 and between 12 and 16 weeks of age and examined for the presence of caudal cervical vertebral malformation. A mixed model for repeated measures data was used to investigate the relationship between the growth rate of the puppies and the fixed effects age, dam, diet, gender and presence of caudal cervical malformation. RESULTS: Five of the puppies had changes consistent with caudal cervical malformation. The diets fed were either balanced or transiently deficient in protein, calcium, phosphorus and/or magnesium. There was no significant association between growth rate and the variables dam, gender and the presence of caudal cervical vertebral malformation. There was no significant association between diet and increase in ulna length, but a trend existed between body weight gain and the feeding of a balanced diet (P = 0.0672). CONCLUSION: Caudal cervical vertebral changes can be detected radiographically as early as 6 weeks of age in some Dobermann puppies. A balanced diet and growth rate are not significant factors in its initial development. 相似文献
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为了掌握海兰褐蛋鸡早期的生长发育规律,运用Gompertz、vonBertalanffy和Richards三种非线性模型对0~10周龄的海兰褐蛋鸡体重数据进行了拟合与分析。结果表明:三种模型均能很好地模拟海兰褐蛋鸡早期的生长过程,拟合度均在0.99以上,但vonBertalanffij模型拟合效果更好,此模型拟合的生长曲线拐点周龄为19.98周,拐点体重为2358.44g,最大周增重为159.94g/周。yonBertalanffy模型在模拟海兰褐蛋鸡早期生长状况方面为理想的数学模型,此研究结果可作为科学饲养该鸡种的重要参考。 相似文献