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991.
1. The objective of this trial was to study the effects of chromium nicotinate (Cr) supplementation on the performance, carcase characteristics and blood constituents of 9 to 22 week-old male turkeys. 2. Fifty-four 8-week-old male turkeys weighing 2.9 +/- 0.28 kg were allocated at random into 9 groups with 3 dietary treatments and 3 replicates. The dietary treatment was different dietary concentrations of chromium in the basal diet, to provide 0 (control), 1 or 3 mg/kg. The feeding trial lasted for 14 weeks. 3. Results showed that 1 mg/kg chromium supplementation significantly improved weight gain and food intake at 9 to 18 weeks of age but did not significantly influence performance at 19 to 22 week of age. The breast and thigh muscle were significantly increased in birds receiving 1 mg/kg chromium supplementation but were decreased by 3 mg/kg of supplementation. 4. Dietary chromium supplementation did not significantly influence other serum constituents, including insulin, HDL, VLDL+LDL, HDL-C, VLDL-C+LDL-C, total protein, albumin, and gamma-globulin at 18 and 22 weeks of age. 5. The serum triacylglycerol (TG) and uric acid contents were significantly increased, while glycerol and alpha-globulin were significantly reduced by 3 mg/kg chromium supplementation. However, 1 mg/kg chromium supplementation significantly reduced serum cholesterol and glycerol at 18-weeks old. At 22 weeks of age, 1 mg/kg chromium supplementation significantly increased serum glucose and decreased the uric acid concentration whereas 3 mg/kg chromium supplementation significantly increased the creatinine concentration and decreased beta-globulin concentration. 相似文献
992.
Kishnani PS Faulkner E VanCamp S Jackson M Brown T Boney A Koeberl D Chen YT 《Veterinary pathology》2001,38(1):83-91
A canine model of glycogen storage disease Ia (GSD Ia), similar clinically, biochemically, and pathologically to the human disease, was established by crossbreeding Maltese and Beagle dogs carrying a mutated, defective glucose-6-phosphatase (G-6-Pase) gene. Ten puppies were born in three litters from these crossbreedings. Six were homozygous for the previously described M121I GSD Ia mutation. Of these six affecteds, two were stillborn, and one died at 2, 32, and 60 days of life, respectively (puppies A, B, C, D, E), while one is alive at age 15 months (puppy F). Affected puppies exhibited tremors, weakness, and neurologic signs when hypoglycemic. They had postnatal growth retardation and progressive hepatomegaly. Biochemical abnormalities included fasting hypoglycemia, hyperlactacidemia, hypercholesterolemia, hypertriglyceridemia, and hyperuricemia. Microscopic examination of tissues from affected puppies showed diffuse, marked hepatocellular vacuolation, with distended clear hepatocytes and central to marginally located rounded nuclei. In the kidneys of puppies D and E, there was segmental glomerular sclerosis and vacuolation of proximal convoluted tubular epithelium. Biochemical analysis revealed increased liver glycogen content and isolated markedly reduced G-6-Pase enzyme activity in liver and kidney. The canine G-6-Pase gene was characterized by screening a canine genomic library. It spans approximately 11.8 kb and consists of five exons with >90% amino acid sequence homology to the derived human sequence. The first 1.5 kb of the 5' region was sequenced and contains several putative response element motifs homologous to the human 5' region. Establishment of this canine colony of GSD Ia that closely resembles human disease and isolation of the canine genomic gene provides an excellent model for studying pathophysiology and long-term complications and an opportunity to develop novel therapeutic approaches such as drug and gene therapy. 相似文献
993.
采用NaF水溶液进行累代或隔代添食的方法,选择"研137"、"丰一"、"7N"、"湘F"四个元母种,组配成四元杂交组合"研·丰×7N·湘F"进行室内及农村试养,并参加广东省新蚕品种品比鉴定.结果表明,该杂交组合耐氟性能强,综合经济性状优于现行生产品种"9·芙×7·湘". 相似文献
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995.
通过几种药剂防除麦田恶性杂草的试验表明,对以碱茅、荠菜为优势杂草的小麦田,宜采用50%异丙隆120 g/667m2 75%巨星1.25 g/667m2的配方,株防效和鲜重防效分别达到95%和100%,同时对小麦安全。 相似文献
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997.
998.
侵染观赏南瓜的黄瓜绿斑驳花叶病毒的初步鉴定 总被引:26,自引:2,他引:26
从广西某农业展示中心观赏南瓜上分离到一种直杆状病毒,长约300nm,该病毒分离物P-3(NN)在测试的葫芦科作物上表现为系统花叶、褪绿斑及明脉症状,在曼陀罗上为局部褪绿斑,在测试的其它茄科作物及豆科和藜科作物上无任何症状反应.其致死温度为95~100℃.经DAC-ELISA测定,P-3(NN)与黄瓜绿斑驳花叶病毒有密切的血清学关系.根据以上结果,初步鉴定P-3(NN)为黄瓜绿斑驳花叶病毒(CGMMV)的一个分离物. 相似文献
999.
1000.