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911.
北大营示范场黑麦草引种与品比试验研究 总被引:5,自引:2,他引:3
利用1998年2-11月在云南省北大营示范场引种的10个黑麦草品种的观测资料,统计分析了在高、中、低3种施肥水平下黑麦草的累计产量、月平均产量及其生长速度的变化规律,研究了影响产量的主导因子及其监测模型。结果表明,在10个品种中,伯生(Bison Intermdiate)及安巴瑟(Embassy)具有良好的生产性能。黑麦草产量主要受气候、土壤肥力及品种等因素的影响,其中测草盘高度、降水量、蒸发量、日照时数和牧草生长天数等5个因子,可以较好地模拟、评估黑麦草产量的变化动态。 相似文献
912.
In this study, supplementation of two levels (5 and 25 parts per million; ppm) of boron into broiler diets including 125 IU kg(-1) (inadequate) and 2000 IU kg(-1) (adequate) vitamin D3 was investigated. The effects of supplementation on performance and biochemical characters (Ca, P, Mg, glucose and AP) of broilers from 1 to 45 days of age were evaluated. Boron provided significant increases in performances of chicks fed both adequate and inadequate vitamin D3-containing diets. The improvements in the inadequate vitamin D3-containing group were higher than that of adequate vitamin D3-containing group. The boron addition had a positive effect on Ca, P and alkaline phosphatase levels of chicks. Boron might be regarded as beneficial in inadequate vitamin D3-containing broiler feed. 相似文献
913.
Mariëlle M.C. Goossens Ad Rijnberk Jan A. Mol Jeannette Wolfswinkel George Voorhout 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1995,9(5):361-365
Central diabetes insipidus was diagnosed by vasopressin measurements during hypertonic stimulation in a 9-year-old male giant Schnauzer with polyuria and polydipsia. The impaired release of vasopressin was believed to be caused by a large pituitary tumor, which was visualized by computed tomography. Studies of the function of the anterior lobe and the pars intermedia of the pituitary gland were conducted, and high concentrations of ACTH and α-melanotrophic hormone (α-MSH) were found without concomitant hyperadrenocorticism. Studies of the molecular size of the immunoreactive ACTH in plasma by gel filtration revealed that most of the circulating immunoreactivity was not ACTH but its precursor pro-opiomelanocortin (POMC) and low-molecular-weight POMC-derived peptides. The pituitary tumor of this dog probably originated from melanotrophic cells of the pars intermedia. The sensitivity of the pituitary-adrenocortical system for the suppressive effect of dexamethasone was unaffected. 相似文献
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918.
J Gr?ndalen 《Nordisk veterinaermedicin》1979,31(2):69-75
Occurrence, clinical and radiographical findings in ununited medial coronoid process in the ulna and osteochondritis dissecans in the humeral condyle in dogs are presented. One hundred and twelve dogs were examined because of forelimb lameness. Lesions were mostly seen in young dogs of heavy breeds especially the Rottweiler. The ratio male: female was about 2:1. Most of the dogs had bilateral lesions. The lameness varied between grade 1 and 3, judged according to a scale ranging from 1 to 5. The affected limbs were somewhat rotated outwards from the elbow and down. Since the ununited coronoid process is almost impossible to detect on a plain radiograph, it is necessary to look for the presence of secondary developed osteophytes, indicative of an arthrosis. Diagnosis is based upon clinical and radiographical findings, the age and the breed of the dog taken into consideration. Osteochondritis dissecans in the humeral condyle is usually easily seen on the dorsopalmar radiograph. 相似文献
919.
P Schmidt V Wiedemann R Kühlmann R Wanke E Linckh U L?sch 《Zentralblatt für Veterin?rmedizin. Reihe B. Journal of veterinary medicine. Series B》1989,36(8):619-628
Specific antibodies directed against enterotoxic E. coli strains from the yolk of immunized hens were exposed in vitro to the influence of varying digestive phenomena like reduction of pH and proteolytic digestion. The remaining antibody activity was tested in a specific ELISA system. It could be shown that already within the stomach a considerable loss in antibody activity caused by a lowering of pH and peptic cleavage can be expected. A further loss in antibody activity is due to the proteolytic effect of the pancreas proteases trypsin and chymotrypsin. It was found that antibodies in protein rich solutions like egg or yolk suspensions were more resistant than mere globulin fractions or antibodies isolated by affinity chromatography. Prospects for further in vivo tests are discussed. 相似文献
920.