Behavior traits and growth characteristics of newly weaned piglets
Four litters of newly weaned piglets (n=37; 7.01 kg BW) were used to evaluate the potential correlations between weight of the piglet, behavioral traits, and growth rate in the first 7 d following weaning. Piglets were weaned at an average of 27 d-of-age and moved into an environmentally controlled nursery facility. Littermate piglets were penned together and allowed ad libitum access to feed and water. Room temperature was maintained between 26 and 32° C. Above each pen a video camera connected to a data storage unit recorded all piglet behaviors. Feed and water disappearance and piglet weight were recorded daily. Video files of piglet behavior were evaluated for frequency (FREQ) and amount of time (TIME) involved in the following behaviors: mobile/active, aggression, eating, and drinking. Piglet weaning weight in wk 1 was negatively correlated (r = -0.47) to weight change as heavier piglets tended to lose more or gain less weight than their lighter weight contemporaries. The daily correlation of weaning weight to weight change was numerically the least (r = -0.25) on d 1, and the greatest on d 4 (r = -0.48). Using pen averages, feed intake increased linearly (P < 0.05) from d 0 to 7, while water intake increased numerically each day. As expected, FREQ and TIME spent eating and drinking increased linearly (P < 0.05) during the first week post-weaning. On d 1, FREQ of eating behavior was not correlated (r = +0.15) to piglet weight change, while FREQ of drinking and aggression were negatively correlated (r = -0.58 and -0.73, respectively) to piglet weight change. On d 2, FREQ of eating and drinking were positively correlated (r = +0.44 and r = +0.72, respectively) to weight change and FREQ of aggression was not correlated (r = +0.25) to piglet weight change. These correlations seem to show that piglets that lost more weight tended to exhibit less inclination towards eating and exhibited more instances of drinking or fighting on d 1. By d 2 to 7, FREQ of eating behavior was positively correlated (r = +0.50) to FREQ of watering behavior and was positively correlated (r = +0.75) to weight change. Data from this study supports previous work where larger piglets tended to lose more weight than smaller piglets post-weaning, which may be due to increased frequency of aggression and water intake on the first day away from the sow.
Keywords: Piglet, Growth, Behavior