Effects of condensed tannin on natural coccidian infection in goat kids

This study was carried out to test the efficacy of a particular type of Quebracho extract, rich in condensed tannins on coccidian infections and growth performances of kids naturally infected with Eimeria spp. Thirty-nine male kids aged 52–81 days were randomly allocated in 4 groups: A control group (CG, 9 kids) and three tannin-treated groups (TG, 10 kids each), that received a feed supplement containing Quebracho tannin (Silvafeed BYPRO Q). During the 45-day study period, kids received the treated feed, regularly once a day according to a varying schedule: For a week in a month (TG1), for a day every 5 days (TG2) and for 3 days every 15 days (TG3). Faecal samples were taken from each kid at 0, 5, 10, 15, 30, 35, 40, 45 days and individual oocyst counts per gram (OPG) were performed using the double FLOTAC® technique. In addition, animals were weighed at 15, 30 and 45 days of the trial. The results showed that the number of Eimeria oocysts in the treated groups decreased since the first 5 study days and was significantly different (P < 0.0001) from study 15-day period onwards. The percentage of oocyst reduction higher than 95% was found in 58% of the kids on study day 5. Comparison in OPG counts obtained from TG groups highlighted that in order to obtain a significant control of the Eimeria population, a high dose or a prolonged administration of Quebracho was required. In fact, OPG counts recorded in the TG1 kids receiving CT for 14 days resulted in the lowest oocyst count. Further, kids from TG2 recorded a lower least-square mean (LSM) value for OPG than the TG3 group showing that a single and more frequent administration of CT (TG2) seems to be more effective than treatments supplied repeatedly for 3 days (TG3). All kids consuming the CT weighed significantly heavier than the kids of the control group, and weight gain of kids from TG2 was higher than those of the other tannin-treated groups.