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91.
C.R. Bjornvad T. Thymann A.Z. Budek D.H. Nielsen C. Mlgaard K.F. Michaelsen P.T. Sangild 《Livestock Science》2007,109(1-3):30-33
Cow's milk stimulates growth in neonates and supplementation with specific milk proteins may benefit immuno-compromized neonates exhibiting poor growth. We investigated the effects of specific milk proteins (casein and whey) and plant protein (hydrolysed soy) on body and organ growth and bone mineralization in colostrum-deprived newborn pigs. Six days after birth, both casein and whey increased body and small intestinal weight relative to soy protein. Villus morphology and epithelial permeability were similar among groups. Casein significantly increased bone mineralization, while whey stimulated soft tissue growth (internal organs, muscle and fat). The differential effects of casein and whey proteins in the early postnatal period show that specific milk proteins rapidly affect whole body and gut development, even in a state of impaired growth induced by artificial feeding of colostrum-deprived pigs. 相似文献
92.
日粮中添加不同酶制剂对肉鸡表观代谢能的影响 总被引:1,自引:0,他引:1
为探讨酶制剂对肉鸡表观代谢能的影响,选用180只21日龄公鸡,分别饲喂A、B、C、D、E、F共6种日粮,A组为正对照组,B组为负对照组,C组为在B组基础上添加0.1%的康地恩复合酶101M,D、E、F组为在B组基础上分别添加0.05%的康地恩复合酶Ⅰ、酶a、酶b.结果表明,C、D、F组表观代谢能显著高于B组(p《0.05),E组与B组差异不显著(P》0.05),C、D、F组之间差异不显著(P》0.05),氮校正代谢能和表观代谢能结论一致.低能量日粮添加0.1%的康地恩复合酶101M、0.05%的康地恩复合酶Ⅰ及酶b可以提高日粮的表观代谢能和氮校正代谢能(P《0.05). 相似文献
93.
樟树叶水浸液对钉螺过氧化物酶等的影响 总被引:1,自引:0,他引:1
用1%~0.1%浓度梯度的新鲜樟树叶的水浸液处理血吸虫的唯一中间寄主———钉螺,设清水饲养为对照。结果表明:樟树叶水浸液处理4~5d后可达到100%的杀灭钉螺效果。采用聚丙稀酰胺电泳技术分离经浓度为1%~0.1%的樟树新鲜叶水浸液处理钉螺样品的过氧化物酶同工酶,经处理24h时样品的酶活高于对照组,而处理48h样品的酶活则大大减弱。由此在微观领域探究了樟树化感作用导致钉螺的病理变化等方面所表现出的杀伤钉螺的机理,获得强他感作用植物樟树灭螺的证据。 相似文献
94.
The purpose of this study was to evaluate oxidative stress and neurotoxic potential of organophosphorus (OP) insecticide diazinon in the sentinel freshwater fish, Oreochromis niloticus. Antioxidant and acetylcholinesterase (AChE) enzyme activities and malondialdehyde (MDA) and protein levels were measured spectrophotometrically in gill, kidney, alimentary tract, and muscle tissues of fish treated with sub-lethal diazinon concentrations for 1, 7, 15, and 30 days. Dose-dependent inhibitions of AChE were observed in all the experimental fish. On the contrary of alimentary tract, MDA levels were elevated in kidney and muscle and gill was not affected. AChE and MDA levels intercorrelated in kidney and muscle tissues. Diazinon had increased superoxide dismutase (SOD) activities in all the tissues, while kidney was the most affected tissue. Tissue-specific alterations were observed on catalase (CAT) and glutathione peroxidase (GPx) activities; however, the activities were not changed in gill and muscle tissues for GPx and in gill, muscle, and kidney tissues for CAT. Protein levels decreased in kidney, muscle, and alimentary tract, while increased in gill and alimentary tract in 15 days. With respect to these results, diazinon has oxidative and neurotoxic potentials in O. niloticus. Observed changes with diazinon treatment were generally tissue-specific and dose-dependent. 相似文献
95.
《The Journal of Applied Poultry Research》2007,16(1):150-159
The potential exists for vitamins and feed enzymes to counteract some metabolic disorders and challenges in poultry. Recent research indicates that increased levels of vitamins E and C are able to reduce ascites-related mortality in broiler chickens. Fatty liver and kidney syndrome is a nutritionally induced metabolic disorder that has been eliminated under practical production conditions due to regular supplementation of poultry diets with biotin. There is also experimental evidence for beneficial effects of 25-hydroxycholecalciferol on the incidence and severity of skeletal and performance anomalies in broilers. Another challenge is the presence of high levels of indigestible and partly soluble nonstarch polysaccharides in many cereals and other plant feed ingredients, resulting in various antinutritive effects. The use of feed enzymes, in particular endo-1,3-1,4-β-glucanase and endo-1,4-β-xylanase, to counteract these adverse effects is well implemented by the feed industry. A typical example of metabolic challenge is the reduced availability of phytate P in plant feed ingredients and the potential for phytate to act as an antinutritional component. Microbial phytase provides a practical solution for improving P availability in plant ingredients. In addition, recent studies suggest phytate can stimulate endogenous losses, and phytase can help prevent those losses. 相似文献
96.
97.
98.
应用单克隆抗体的免疫组织化学法研究雏鸭体内鸭瘟病毒的分布 总被引:3,自引:1,他引:3
本实验应用了免疫组织化学的单克隆抗体间接酶标染色法,对人工感染鸭瘟病毒雏鸭的组织切片进行染色观察。旨在研究病毒在鸭体内分布,对其进行定位。研究结果显示,鸭的心脏、肝脏、脾、胸腺、肠、法氏囊、胰、肺、肾等组织的细胞浆内均出现了染色的特异阳性反应物。结果表明,鸭瘟病毒广泛分布于感染雏鸭的各种组织器官,并造成一定的组织病理变化。 相似文献
99.
膨化与加酶玉米对断奶仔猪生长性能和肠黏膜形态的影响 总被引:1,自引:0,他引:1
通过2个饲养试验,研究了膨化及加酶处理玉米对断奶仔猪的生长性能和肠黏膜形态的影响。试验一分别用普通玉米、膨化玉米、普通玉米加酶及膨化玉米加酶为主要能量原料的饲料饲喂仔猪做4种处理,每个处理6个重复,定时记录体质量和耗料量.计算日增重、日采食量和料肉比。结果表明,膨化和加酶玉米均可提高日增重,降低料肉比。试验二分别用普通玉米、膨化玉米、普通玉米加酶及膨化玉米加酶为主要能量原料的饲料饲喂仔猪做4种处理,每个处理6个重复,分别在断奶后第14天和第28天各屠宰1头公猪。取十二指肠、空肠前、中、后段以及回肠做组织切片,观察其黏膜厚度、绒毛高度、隐窝深度和绒毛宽度。结果表明,断奶后14d,与普通玉米组相比,膨化玉米组和加酶玉米组都显著提高了十二指肠的绒毛高度,二者共同处理组使十二指肠的绒毛高度极显著提高;2种处理组都显著降低了空肠中段的隐窝深度;显著增加了十二指肠、空肠前段、后段和回肠的黏膜厚度。断奶后28d,2种处理组都显著增加了十二指肠的黏膜厚度。 相似文献
100.