系统发生学与进化生物学杂志

Effect of Weaning Age on Stress-Related Behavior in Foals (Equus Caballus) by Abrupt - Group Weaning Method

Abstract

Haixia Xiao, Tuohuti Ajide, Li Zhang, Guobin Lu, Guoqing Shi and Hai Li

Weaning is one of the most stressful periods in a foal’s life. The traditional and most common weaning method is total and abrupt in China. The purpose of the research was to examine the stress-related behavioral response of foals and find the optimal weaning age by using abrupt and group weaning method. A total of 15 thoroughbred mare-foal pairs were divided into three groups A (6-month foals, n=5), B (7-month foals, n=5) and C (8-month foals, n=5) according to the weaning age. These foals were observed for 3 days before weaning and 9 days after separation, and 15 behavioral patterns were compiled. All statistical analysis was performed by R2.14.2 (R Development Core Team). Comparing to pre-weaning, frequency of drinking, urination, fast-moving, aggression behaviors increased and the frequency of standing, lying and individual rolling behaviors decreased after separation for three groups. On the weaning day (Day 0), drinking, urination, social game, friend were most pronounced and standing, slow-moving, individual rolling was least pronounced in foals of group A (p<0.05). Except for the same pronounce with group A, the frequency of fast-moving and individual nibbling were the highest in foals of group B (0.53 ± 0.49, 0.77 ± 0.15 times /h, respectively) and the frequency of defecation, social kidding, individual nibbling behaviors were the highest in foals of group C (0.38 ± 0.11, 1.75 ± 0.87, 0.71 ± 0.08 times /h, respectively) on the weaning day, whilst the frequency of slow-moving were strongly decreased in foals of group B (10.88 ± 0.69 times /h) and the frequency of social suck were strongly decreased in foals of group C (0.33 ± 0.07 times /h ) on the weaning day. 8, 12 and 13 behavior categories had changes in group A, group B and group C during the observation phase. Weaning is associated with stress but 6-month years old was least pronounced in foals by abrupt - group weaning method in China.