Fayer R, Lynch G P
Parasitology. 1979 Dec;79(3):325-36. doi: 10.1017/s0031182000053737.
Two 8-week experiments were conducted to determine the relationships between nutritional stress and pathophysiological changes in male Holstein calves infected with Sarcocystis cruzi. Calves were infected by oral inoculation with 200 000 S. cruzi sporocysts. In the first experiment weight gain reduction was greatest in inoculated calves during weeks 4 and 5 after inoculation. Feed intake was reduced during the 5th week. Erythrocyte count was reduced during week 5 and haemoglobin was reduced during week 6. The 24-h excretion of urinary and urea nitrogen from the inoculated calves was increased by treatment. In the 2nd experiments, both the feed-restricted and inoculated calves lost weight during weeks 4 and 5; feed intake was lower from week 5 to 8 inclusive. Urine volume from inoculated calves was lower during week 8. Lower urine excretions of sodium and potassium resulted from S. cruzi inoculation. There was a non-significant trend for higher urinary zinc excretion in the inoculated group during week 4. Urine nitrogen excretion from inoculated calves was higher during week 6. The urinary excretion of 3-methylhistidine from the inoculated calves was higher during week 4 and excretion of guanine was higher during weeks 4, 5 and 8. S. cruzi has several specific pathophysiological effects on calves beyond those induced by nutritional stress.
进行了两项为期8周的实验，以确定感染克氏肉孢子虫的雄性荷斯坦犊牛营养应激与病理生理变化之间的关系。通过口服接种20万个克氏肉孢子虫孢子囊使犊牛感染。在第一个实验中，接种后的第4周和第5周，接种犊牛的体重减轻最为明显。第5周期间采食量减少。第5周红细胞计数减少，第6周血红蛋白减少。接种犊牛24小时尿氮和尿素氮排泄量因处理而增加。在第二个实验中，限饲组和接种组犊牛在第4周和第5周体重均下降；从第5周到第8周（含第8周）采食量较低。接种犊牛在第8周尿量较低。克氏肉孢子虫接种导致钠和钾的尿排泄量降低。接种组在第4周尿锌排泄量有升高的趋势，但不显著。接种犊牛在第6周尿氮排泄量较高。接种犊牛在第4周3-甲基组氨酸的尿排泄量较高，在第4周、第5周和第8周鸟嘌呤的排泄量较高。除营养应激所诱发的影响外，克氏肉孢子虫对犊牛还有几种特定的病理生理效应。
