Jarvie B D, Trotz-Williams L A, McKnight D R, Leslie K E, Wallace M M, Todd C G, Sharpe P H, Peregrine A S
Department of Population Medicine, Ontario Veterinary College, University of Guelph Ontario, Canada, N1G 2W1.
J Dairy Sci. 2005 May;88(5):1801-6. doi: 10.3168/jds.S0022-0302(05)72854-X.
Thirty-one Holstein bull calves were purchased at birth from 3 dairy farms in Eastern Ontario. Each calf was assigned at random to oral treatment with either 5 mg of halofuginone lactate in 10.0 mL of aqueous carrier solution (Halocur, base comprised 10 mg of benzoic acid, 100 mg of lactic acid, and 0.3 mg of tartrazine) or 10 mL of placebo (Halocur base minus the active ingredient, halofuginone lactate) administered 15 to 30 min after morning milk feeding for the first 7 d of life. Intakes of milk, calf starter, and water, and fecal consistency score were recorded daily for 56 d. Calf weights were recorded weekly for 56 d. Fecal samples were taken from all calves at approximately 2, 7, 14, 21, and 28 d of age for isolation of Cryptosporidium parvum oocysts. Logistic and linear regression analyses were used to assess the effect of treatment on the incidence of diarrhea and C. parvum infection status. The odds of C. parvum shedding among calves in the halofuginone lactate-treated group was 70% lower than the odds of shedding among calves in the placebo group. In calves treated with halofuginone lactate, no oocyst shedding occurred until 2 wk of age, whereas 12.5% of calves in the placebo group began shedding oocysts during wk 1. From all ages of placebo-treated calves, 31 of 73 samples (42.5%) were positive for C. parvum, whereas only 15 of 67 samples (22.4%) from all ages of halofuginone lactate-treated calves tested positive. The largest number of C. parvum-positive samples occurred in the third week of life. There was a significant delay of 3.1 d in the incidence of diarrhea among calves treated with halofuginone lactate. Intake of milk and starter, body weight gains, and age at weaning were not significantly different between treatment groups.
从安大略省东部的3个奶牛场购买了31头荷斯坦公牛犊，这些牛犊均在出生时购入。每头小牛被随机分配接受口服治疗，一组在出生后第1周的每天早晨喂奶后15至30分钟，给予10.0 mL含5 mg乳酸盐卤夫酮的水性载体溶液（Halocur，基质包含10 mg苯甲酸、100 mg乳酸和0.3 mg柠檬黄），另一组给予10 mL安慰剂（不含活性成分乳酸盐卤夫酮的Halocur基质），持续7天。在56天内每天记录牛奶、犊牛开食料和水的摄入量以及粪便稠度评分。在56天内每周记录犊牛体重。在大约2、7、14、21和28日龄时从所有犊牛采集粪便样本，用于分离微小隐孢子虫卵囊。采用逻辑回归和线性回归分析评估治疗对腹泻发病率和微小隐孢子虫感染状况的影响。乳酸盐卤夫酮治疗组犊牛排出微小隐孢子虫的几率比安慰剂组犊牛低70%。在用乳酸盐卤夫酮治疗的犊牛中，直到2周龄才出现卵囊排出，而安慰剂组12.5%的犊牛在第1周开始排出卵囊。在所有年龄的安慰剂治疗犊牛中，73份样本中有31份（42.5%）微小隐孢子虫呈阳性，而在所有年龄的乳酸盐卤夫酮治疗犊牛中，67份样本中只有15份（22.4%）检测呈阳性。微小隐孢子虫阳性样本数量最多出现在出生后第三周。用乳酸盐卤夫酮治疗的犊牛腹泻发病率显著延迟3.1天。治疗组之间牛奶和开食料的摄入量、体重增加以及断奶年龄没有显著差异。
