Efecto del peso al nacer, tamaño de camada y posición en la ubre sobre el crecimiento de cerdos durante la lactancia y engorda

Growth during lactation and feeding was evaluated for low birth weight (runt) piglets in 32 high prolificacy litters using three birth weight categories (low, medium, and high) and three litter sizes (small, medium and large). The teat secured during birth and lactation by each studied piglet was identified. An analysis was done of the effects of the birth weight and litter size categories the variables weight and weight gain during lactation and feeding; back fat; loin depth; and carcass yield at 160 d. High prolificacy litters had a higher proportion of low birth weight piglets (26 %) than low prolificacy litters (4 %). Low birth weight piglets took longer to suck the teat (50.37 min) than the medium (32.44 min) and high weight piglets (24.34 min). Most (67 %) of the runts were positioned largely on the sow’s posterior teats. Low weight piglets exhibited lower weight gain (181 g/d) than the medium (211 g/d) and high weight piglets (240 g/d). Their weight at 160 d (86.6 kg) was also lower than in the medium (95.7 kg) and high weight piglets (101.1 kg). In high prolificacy litters, low weight piglets (runts) exhibited the lowest growth performance, independent of litter size and lactation teat.