Piglet mortality in organic herds

Summary

Productive performance of organic pig farms is lower compared to conventional farms, but only very few data exist. Better knowledge of the productivity of organic herds regarding litter size at birth, piglet losses around birth and during lactation, as well as housing and management conditions should help to identify critical points and hence to improve the situation. Therefore, a research project was initiated in 6 EU countries (Corepig). As part of this, farmers recorded production data during 3-11 months starting between January and July 2008. Farmers were asked to record the numbers of piglets born dead, born alive as well as the number of piglets at weaning. Taking into account the quality of the records and setting a threshold of ≥ 10 litters/farm, data from 38 farms in 4 countries (France: 14, Germany: 12, Austria: 7, Sweden: 5) were analyzed (mean: 69, 10 to 713 litters/farm). Most farmers were not present at farrowing, meaning the number of piglets that were classified as “born dead” was probably greatly overestimated. Therefore, mean total litter size at birth (born dead + born alive, MTLS), its standard deviation (SDLS), litter size at weaning and percentage of total losses (born dead + lactation losses, pLOSS) were calculated at the farm level. Overall, MTLS was 12.9 ± 1.6 piglets at birth, 9.2 ± 1.1 piglets at weaning and pLOSS was 26.7 ± 7.1 % with a lactation duration of 45.3 ± 5.9 days. Mortality of piglets increased with MTLS (2.1 ± 0.7% additional loss per piglet, p = 0.004) and with SDLS (3.9 ± 1.6% additional loss per unit of SDLS, mean ± SEM, P = 0.021). MTLS was correlated with SDLS (r = 0.44, p = 0.006). These data confirm the detrimental influence of large litter size at birth on piglet mortality. This is commonly observed in conventional pig production and related to a higher proportion of piglets with low birth weight and to increased competition for teats. High variability in litter size may exacerbate these problems, and in addition may be an indicator for other problems on the farm.