The ‘teat order’ of suckling pigs: I. Relation to birth weight and subsequent growth

Abstract

Teat orders were determined for 76 litters of Large White and Large White × Landrace pigs. Regression analysis within litters revealed a relationship between suckling position and weight both at birth (P<0·01) and at 3 weeks of age (P<0·001), with the heavier piglets tending to occupy the more anterior teats. The correlation coefficients, however, were very small (r = –0·16 and –0·22 respectively). The correlation between birth weight and 3-week weight was much larger (r = +0·47); and a comparison of pairs of litter-mates showed that a difference in birth weight of 0·25 kg or more persisted at 3 weeks in the majority of cases, regardless of which piglet suckled the more anterior teat. Birth weight accounted for much more of the variation in 3-week weight than did teat number, and, when the effect of birth weight had been taken into account, teat number accounted for only an additional 2·3% of the variation. Even so, the anterior teats did appear to confer some advantage which was independent of that of the birth weight of the piglets suckling these teats. From the results of this and other studies it is concluded that there is only a weak relationship between suckling position and weight at birth and 3 weeks. Other unidentified factors are probably of more importance for the within-litter variation in weight gain of suckling pigs.