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用堆型艾美耳球虫早熟株对雏鸡进行一次免疫和二次免疫试验 ,研究雏鸡血清抗体的动态变化。试验结果显示 ,在一次免疫试验中 ,各剂量组雏鸡均在免疫后 2天血清抗体出现较高的 OD值 ,之后呈下降趋势 ,11天后逐渐上升 ,到 12~ 13天时出现第 2个峰值 ,各组间的血清抗体 OD值比较 ,3 0 0 0个卵囊 /只剂量组极显著 (P<0 .0 1)高于 10 0 0个 /只、2 0 0 0个 /只和 5 0 0 0个 /只剂量组。在二次免疫试验中 ,8日龄首免、14日龄二免组雏鸡的抗体水平动态变化整体呈上升趋势 ,峰值 (0 .3 75 )出现在二免后第 10天 ,其后稳定地维持在较高水平 (平均 OD值为 0 .3 5 ) ,并且其抗体水平显著地高于 6日龄首免、12日龄二免组 (P<0 .0 5 )。抗体水平动态变化表明 ,堆型艾美耳球虫早熟株有较强的免疫保护力 ,其免疫方式可选用一次免疫 ,剂量为 3 0 0 0个卵囊 /只 ,也可采用二次免疫 ,即 8日龄首免 (15 0 0个 /只 ) ,14日龄二免 (15 0 0个 /只 ) ,从抗体动态变化的稳定性看 ,二次免疫更佳 相似文献
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A single, artificially-induced fly-strike with Lucilia sericata larvae was associated with a rapid (decline in food intake in sheep, with a consequent reduction in liveweight. Loss of weight ranged from 0.5 to 5.5 kg over four to six days and recovery to pre-infestation liveweight took three to 36 days. Pair-fed, uninfested partners of these sheep also showed a reduction in liveweight, whereas uninfested sheep in some experiments fed ad libitum showed either little change or a gain in liveweight over the same period. In general, maggot infested sheep took less time to regain weight than did their pair-fed partners although the weight lost as a proportion of initial weight was similar in both groups. Loss of appetite alone would appear to account for these events. 相似文献
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Corneal sequestrum was diagnosed upon clinical examination of 12 cats. The cornea of seven were examined histologically and had focal necrosis and inflammation of the stroma and epithelium. As the simple excision of the corneal lesions had been unsuccessful in two of the cats, repair of these was effected by construction of a tarso-conjunctival pedicle flap after the excision of the sequestrum. 相似文献
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Kerckhoff AC 《Science (New York, N.Y.)》1988,239(4842):922-923
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A condition resembling chronic malignant catarrhal fever was seen in a 9-month-old pet sika hind (Cervus nippon). From an initial acute depression, pyrexia, and anorexia, the condition progressed to include hypopyon, keratitis, lethargy, loss of condition, sloughing of one hoof and eventually death after seven weeks. There were multiple, 5 to 8mm diameter dark-red nodules throughout the mesenteries and mediastinum, along abdominal organ ligaments, and about the uterus and kidneys. Histopathology showed the nodules to be organising vascular thrombi. Concurrent perivascular mononuclear infiltrations and intravascular thrombi in many tissues confirmed that the condition was malignant catarrhal fever. 相似文献
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The pathology of carcinoma of the small intestine in six adult cattle is described. The lesions were similar to those of carcinoma of the small intestine of sheep although a slightly less fibrous stroma and a greater tendency to metastasise was observed. Initial findings suggest the disease resembles small-intestinal carcinoma of sheep and cola-rectal carcinomas of man in having a higher prevalence in New Zealand than most other countries. This highlights the need to investigate common environmental factors which may be responsible for the induction and promotion of these tumours in both grazing ruminants and man. 相似文献