Impact of Piglet Birth Weight, Birth Order and Litter Size on Subsequent Growth Performance, Carcass Quality, Muscle Composition and Eating Quality of Pork

May 6, 2010 — 

The objective of this study was to investigate the relationships between birth weight, birth order or litter size on growth performance, carcass quality and eating quality of the ultimate pork product. Data were collected from 98 pig litters and, with the addition of recording birth weight and birth order, farrowing and piglet management were according to normal barn practices. In the nursery and during growout, the pigs received the normal feeding program for the barn and, with the addition of individual tattooing, were marketed as per normal. From 24 litters, selected because they had at least 12 pigs born alive and represented a range of birth weights, 4 piglets were chosen (for a total of 96 piglets) and sent to AAFC-Lacombe Research Centre (Lacombe, AB, Canada) when they reached 120 kg for extensive meat quality and sensory analysis. Individual BW was measured at birth, on the day of weaning, 5 wk after weaning, at nursery exit, at first pull and at the time of marketing. Litter sizes were divided into 3 categories: small (3 to 10 piglets), medium (11 to 13 piglets) and large (14 to 19 piglets). There were 4 birth weight quartiles: 0.80 to 1.20, 1.25 to 1.45, 1.50 to 1.70 and 1.75 to 2.50 kg. Increased litter size resulted in reduced mean birth weight (P < 0.05), but had no effect on within litter variability or carcass quality (P > 0.05) when slaughtered at the same endpoint. Lower birth weight pigs had reduced BW at weaning, 5 and 7 wk post-weaning and at first pull and had increased days to market (P < 0.05). Birth weight had limited effects on carcass quality, weight of primal cuts, objective quality and overall palatability of the meat at the same slaughter weight (P > 0.05). In conclusion, increased litter size resulted in decreased mean birth weight but no change in days to market. Lower birth weight pigs took longer to reach market. Despite some differences in histological properties, birth weight had limited effects on carcass composition or final eating quality of the pork when slaughtered at the same liveweight and large litter size resulted in more pigs weaned and marketed compared to the smaller litters. We concluded that based on the conditions of this study, other than increased days to market, there is no reason based on pig performance or pork quality to slow down the pork industry's drive to increase sow productivity as a means to increase efficiency.

Beaulieu AD, Aalhus JL, Williams NH, Patience JF, Impact of piglet birth weight, birth order and litter size on subsequent growth performance, carcass quality, muscle composition and eating quality of pork, J Anim Sci. 2010 Apr 23. [Epub ahead of print]