Perfil de natimortalidade de acordo com ordem de nascimento, peso e sexo de leitões

Abstract

To examine the influence of birth order, gender, and birth weight of piglets on stillbirth, records of 575 farrowings were analyzed. Out of 7,061 piglets, 90.2%, 6.0%, and 3.8% were born alive, stillborns and mummified, respectively. The percentage of farrowings with stillborns was 44.5%. Farrowings with two or more stillborns accounted for 63.1% of losses, although they produced 17.2% of the litters. Stillbirth rate increased with the increase of the birth order. Piglets born from the 14th order onward had the highest stillbirth rate (21.7%). Piglets born from the 1st to the 9th and from the 10th to the 13th order had stillbirth rates of 3.6% and 10.1%, respectively. For piglets weighting up to 500g, the stillbirth rate was 52.1%, which was higher than that recorded for heavier piglets. Piglets weighting from 501 to 1,200g had a stillbirth rate of 10.1%, which was higher than that observed for piglets weighing more than 1,200g (4.0%). There was no effect of gender of piglets on stillbirth occurrence, which reachead 6.2% and 5.8% for males and females, respectively. The stillbirth occurrence was higher for low weight piglets or higher birth order. © 2008 Escola de Veterinária UFMG.