Some factors affecting piglet survival

Abstract

The aim of this study was to evaluate the factors that cause losses of piglets on family farms. Effects that may be related to piglet mortality include breed, season of birth, sow parity, age of sow, farmer, litter size at birth and birth weight of piglet. Data consisted of 21,721 litters from the years 2005-2009. Statistical analyses were performed using the SAS package. Piglet losses until weaning per farmer and month were analysed. The model included: genotype, season as year × month interaction, parity, breeder, litter size and lactation length as linear regression. Breeders and season were treated as random effects. Only maternal genotypes of sows were included: Slovenian Landrace (SL), Slovenian Large White (SLW) and crosses SL×SLW and SLW×SL. Lactation lasted 32 days on average and sows had 4 parities. Piglet losses on Slovenian family farms are around 10%. The smallest losses occurred in the first three parities. Differences among individual breeders were significant. Higher losses were related with longer lactations. Cross fostering of piglets among litter presented a problem, as it was not recorded by farmers and as such losses per litter could not be analysed.