The temporal patterns of food intake and allelomimetic feeding by pigs of different ages

Abstract

The feeding behaviour of 4 castrated boars was studied over 24 hours using a photoelectric cell and continuous recorder at 4 body-weight stages, viz. 20, 40, 60 and 80 kg. Two of the pigs were on continuous light, and 2 were on 8.5 h light and 15.5 h of darkness. The 2 pigs in each treatment were in adjacent stalls but well separated from the other pair and other pigs. There were no differences in total food consumption between the animals in the 2 treatments. Eating speed also did not differ between treatments; neither did it differ between body-weight stages when adjusted for body weight. The percentage of the total time devoted to feeding differed between body-weight stages but not between treatments. However, over the first 8-h period of the day, the pigs on the short day-length spent more time feeding, but body weight did not affect this measure. Meal intervals were determined by a logarithm survivorship curve analysis, and it was found that pigs on the long day-length had significantly more meals than the others. Body weight also affected the number of meals, with the youngest taking most. Furthermore, both pairs showed a significant degree of synchronized feeding.