ONTOGENY OF TEAT FIDELITY IN PIGS AND ITS RELATION TO COMPETITION AT SUCKLING

Abstract

The suckling behavior of 55 piglets from six litters was observed daily from birth to 10 d of age to describe the development of teat preference, teat fidelity and teat disputes and to relate these to weight gain. The percentage of piglets suckling from only one teat pair on each day increased from less than 5% on day 1 to 85% on day 10. By 3 d of age, the piglets had chosen their preferred teat pair, since 75% kept the same preferred teat pair between 3 and 10 d of age. The mean percent of nursings on the preferred teat pair increased from 50 to 86% during the first 3 d, and reached 95% on day 10. Teat disputes were most frequent on day 1 and missed nursings most frequent on day 2; frequency of both decreased as the piglets aged. On day 1, piglets that won most of their teat disputes suckled more frequently and had greater 3-d weight gains. After day 1, piglets that gained more weight were more consistent in the use of their preferred teat, pair, had fewer teat disputes and missed fewer nursings. Success at teat disputes was not related to weight gain after day 3. Typically, piglets suckled successfully; most of the variation in suckling behavior was due to the existence of "problem" pigs that were inconsistent in their use of teats, and were involved in teat disputes and missed nursings. Anterior teats were used more often. Piglets suckling from teats in the middle of the udder had a lower teat fidelity than those suckling at either end. Piglets suckling anterior teats gained more weight only between days 4 and 6. This effect disappeared once initial body weight and missed nursings were accounted for. We suggest that a high level of teat fidelity is an advantage to piglets because it reduces teat disputes and the chance of missing nursings. Key words: Piglet, suckling behavior, weight gain, teat order, fighting, teat disputes