ANALYSIS OF CAUSES OF PIGLET MORTALITY BEFORE WEANING - INFLUENCE OF BREED AND PARITY

The mortality of piglets before weaning was analyzed in an experimental herds. The breed of parents, either Large White (LW) or Pietrain (PP) and the parity of the litter were studied. From 1973-1978, 1020 litters were registered, with 9510 piglets born, of which 8903 were born alive; there were 519 liters from gilts (154 from 2 PP parents and 348 from 2 LW parents) and 501 2nd litters (154 from 2 PP parents and 347 from PP sire and LW dam). The average rate of stillborn piglets was 6.4%, it was significantly higher for piglets from PP than for those from LW dam; the average rate of death during the suckling period was 20.8%; it was significantly lower for PP .times. LW piglets than for other breeds. The number and rate of dead piglet significantly increased with the prolificacy of the dam. Four main causes representing 72% of mortality cases before weaning were trampled down by the dam (35.4% of cases), important whatever the breed or the parity; splayleg (14%), significantly higher for piglets from 1 or 2 PP parents; weakness of piglets at birth (11.6%) higher in 1st litters and for LW dams; and total or parital aglactia of dam (11%) more frequent in LW sows. The death was very quick (75% of cases during the 1st wk, 50% the day of birth of the following day), especially in cases of splayleg. These data are compared with those of the literature; the importance of housing, the influence of breed upon rate and causes of mortality and the interest of crossbreeding for improving the survival rate of piglets are emphasized.