The behaviour of foals before and after weaning in group

Sammanfattning: Weaning is a standard procedure at most studs, and the methods of weaning varies greatly. The method used at the stud in this particular study is supposed to decrease stress. The purpose of the study was to compare the behaviour of foals in group before and after stepwise removal of their mares. Standardbred foals with their mothers were kept in three different groups at pasture (12, 11 and 11 foals, respectively, mixed sexes). They had free access to silage and the foals were fed concentrate in a creep-feeding area. By the time the foals were 5 months old, the mares were stepwise removed from the pasture. Every or every second day, 2-4 mares were removed, until all mares were gone. The mares were placed so that the foals could not hear or see them. The foals remained in their original group at the pasture throughout the whole weaning process. Observations were performed daily in two hour-shifts from the day before the first removal until the day after the last removal of mares. The three groups were observed for 28, 26 and 20 hours, respectively. A total of 24 different behaviours were recorded, some continuously and others every second minute. Means for periods of 14 minutes were calculated and analysed by the GLM procedure, the Statistical Analysis System. The time budgets of the three groups were very similar to each other. Also the time budgets before and after removal of mares were similar. This indicates that the foals adapted quickly to the new situation. Perhaps this quick adaptation was possible because of the otherwise familiar circumstances. On removal days, the foals without dams were both running and walking more and they were also more vocal than the foals with dams. Apparently, the foals were upset by the removal of their dams. Also on removal days, all foals, both with and without dams, spent less time resting and less time in a recumbent position. This shows that all foals in the group were disturbed on removal days. During days after removal days, the foals without dams spent less time resting alone and less time in lateral recumbency than foals with dams. This indicates that the foals without dams still had not adapted to the new situation. After removal of all mares, the total time of resting were no less than before the removal of mares, but the foals had changed their resting behaviour. Since the foals spent less time in lateral recumbency one might assume that they did not get enough of the important REM-sleep. While the foals still had access to their dams and were able to suckle, they ended the majority of the nursing bouts. This shows that the mares had not yet began to wean their foals themselves. Still twelve days after the first group had been weaned, we noticed that the foals were trying to suckle on each other. For a foal which is developing very rapidly at this age, the separation from it’s dam is a major psychological trauma. The traumatic experience may be irreversible, and will lay a foundation to the development of stereotypies. The subject of weaning foals need more research. This study show that weaning by stepwise removal of the mares from pasture, leaving the foals in a familiar surrounding, is a good weaning method. However, the timing of the weaning, at the age of five months, is too soon for the foals. When and how to wean the foals should be based on knowledge of the horse’s natural behaviour and not tradition.