The influence of colostrum on infection of calves around 7 months of age with Schistosoma mattheei

Abstract

Studies have indicated that the intake of colostrum could modulate the offspring reaction towards early schistosome infections. The effect of colostrum (containing immunoglobulins, parasite antigens, immune cells and other cell-related products) on late Schistosoma infections is to our knowledge not documented. The objective of the present study is to determine whether the intake of colostrum from Schistosoma mattheei infected cows will modify late S. mattheei infection patterns in their offspring. Six calves born to confirmed non-infected cows and 10 calves born to confirmed infected mothers were purchased after intake of colostrum. All calves were exposed to a total experimental challenge of 2500 cercariae around the age of 7 months. Serum samples were collected before and after intake of colostrum and monthly thereafter for the determination of specific antibody levels. Faecal samples were collected monthly from 42 days after infection for the determination of faecal egg counts. Six calves of each group were slaughtered around the age of 15 months for worm recovery and tissue egg counting. No differences between both groups were observed in immunoglobulin levels and faecal egg counts after infection, and in worm counts and tissue egg counts at necropsy. In conclusion colostral effects, which were noticed at an early age, are no longer present around the age of 7 months. As such calves which are born during a season of high Schistosoma transmission will still be under colostral influence and therefore be more protected against a primary challenge than calves born during a low transmission season, as the latter will only receive their first challenge when colostral protective effects have disappeared.