[Effect of a paramunity inducer on the incidence of diseases and the plasma cortisol content in Thoroughbred foals before and after weaning].

The effect of the prophylactic application of the paramunity inducer Baypamun on the incidence of diseases among foals (n = 63) in four Thoroughbred studs was evaluated. In a blind study, 38 of the foals received 2 ml of Baypamun intramuscularly while 25 of the foals received a placebo at six and four days before weaning and on the fifth day post-weaning. During the observation period of three weeks, beginning with the first and ending ten days after the last application, 7.9% of the foals treated with Baypamun (3 out of 38) suffered from respiratory infections compared to 24% of the foals treated with placebo (6 out of 25). The blood plasma cortisol concentrations were also measured in 53 of the foals of three studs before and 24 hours after weaning. The cortisol concentration increased in all the foals. However, the increase was significant only for the Baypamun treated foals of one stud while it was significant for the placebo treated foals of all studs (p < 0.01).