Factors associated with average pig weight at weaning on farms using early weaning

Abstract The objective of this study was to investigate the effect of various factors on average pig weight at weaning on farms using early weaning. Farms were selected based on average weaning age and whether they recorded lactation food intake and litter weights at weaning. The database contained 9834 litter weights and 8903 food intake records. Average pig weight at weaning, litter size at weaning, weaning age, and average daily food intake during lactation (ADFl) were 4·9 (s.d. 1·0) kg, 9·3 (s.d. 1·6) pigs, 16·8 (s.d. 2·8) days, and 4·9 (s.d. 1·1) kg, respectively. Litter size, weaning age, parity, farrowing season, and ADFl groups influenced average pig weight at weaning (P < 0·01). Three two-way interactions between parity and season, weaning age and farrowing season, and weaning age and ADFl groups were found fP < 0·01). Average pig weights for litter sizes between six and 10 were higher than those between litter sizes one and four, and 11 and 22. Parity 1 sows produced lighter pig weights than any other parity group during any other season (P < 0·01). Average weights of weaned pigs farrowed during the summer in all parities groups were lighter (P < 0·01) than those during the autumn. Pig weights for weaning ages between 22 and 21 days during the summer tended to be lighter than those during the autumn. Pigs weaned between days 16 and 22 of age in the high ADFI group (>5·6 kg) were heavier (P < 0·01) than those in the low ADFl (> 4·2 kg) group.