The effect of kaolin feeding on efficiency, health status and course of diarrhoeal infections caused by enterotoxigenic <i>Escherichia coli</i> strains in weaned piglets

The purpose of the present study was to assess the effect of kaolin feeding on health status, body weight gain (BWG), course of diarrhoeal infections caused by enterotoxigenic strains of <i>Escherichia coli</i> (ETEC) and the level of mycobacterial contamination in weaned piglets. The testing was performed in two experiments involving 40 weaned piglets at the age of 28 days. In the infection-free experiment, piglets were fed a diet without (C0) or with 1% content of kaolin (K0) for 20 days. Subsequently, all of them were fed the same diet without kaolin supplementation for 39 days. Identical diets were fed during the infection experiment, and moreover, both groups (CI and KI) were orally infected with ETEC (O141:F18ac, STa+) on Day 1 of experiment. The short-term feeding of kaolin to weaned piglets had a significant positive effect on their BWG. During the period of feeding the kaolin-containing diets, BWG in C0 and K0 were 0.20 and 0.29 kg, respectively (<i>P</i> < 0.05), and in CI and KI 0.13 and 0.19 kg, respectively (<i>P</i> < 0.05). There was no evidence of side effects to their health, neither was there any change in biochemical and haematological profiles. In the infection experiment, a protective effect of kaolin on the course of ETEC infection was evident. Colonization and shedding of ETEC by piglets fed the kaolin diet were milder and had a shorter duration in comparison with control piglets. The culture examination of pure kaolin and kaolin containing diets for mycobacteria were negative. Potentially pathogenic mycobacteria occurring in the environment were isolated from faeces and tissues of pigs. According to these results, supplementation of diets with 1% kaolin to prevent diarrhoea in piglets and to support their growth in the critical post-weaning period could be recommended.