断奶仔猪混群后社会等级重建及生产性能研究

为探讨不同品种断奶仔猪混群后社会等级重建过程中行为差异及其对仔猪生长发育的影响,通过行为评定划分断奶仔猪社会等级,比较保育期民猪仔猪和大白猪仔猪行为差异,分析社会等级与断奶仔猪生产性能关系。采用全事件记录法观测和记录仔猪争斗行为,利用二元交互水平社会关系测量方法确定个体优势等级。研究表明,大白猪仔猪争斗行为次数随所处等级位置升高而增加,民猪仔猪争斗行为次数与其所处等级位置无明显关系;与大白猪相比,民猪仔猪混群后争斗行为次数远低于大白猪仔猪,群居秩序较早达稳定状态;民猪仔猪皮肤损伤程度与所处等级位置呈显著负相关(P<0.05),大白猪仔猪皮肤损伤程度与所处等级位置呈显著正相关(P<0.05)。民猪仔猪等级指数与断奶重存在显著正相关(P<0.05),大白猪仔猪等级指数与断奶重、相对生长速率、日增重均存在显著正相关(P<0.05)。可见,群体结构发生改变时,民猪仔猪争斗行为较少,对新环境适应性较强,群体内社会等级重建对其生产性能影响较小,民猪仔猪更适合混群饲养。

Study on social rank reconstruction of weaning piglets after mixing and its relationship with the growth performance

In order to investigate the behavioral discrepancy of weaning piglets and its influences on the growth performance in different breeds during the process of social rank reconstruction after mixing of weaning, the behaviors between Minpig piglets and Large White piglets during nursery period were compared in this study in order to discuss the relationship of social rank and the growth performance of weaning piglets. The social rank of weaning piglets was determined by behavioral evaluation. The agonistic behavior of every piglet was observed and recorded by the method of full event recording, and used Dyadic Level to determine the dominance rank by rank index. The results showed that the frequency of fighting behavior of Large White piglets increased with the higher rankposition, but there was no significant relationship between the social rank and the frequency of fighting behavior in Minpig group. Moreover, the frequency of fighting behavior in Min pig piglets was lower than that in Large White piglets. Compared with Large White piglets, the social order in Minpig piglets reached stable state quickly. There was a significant negative correlation between the degree of skin lesions and the position of rank(P<0.05) in Min pig piglets, but there was a positive correlation between the degree of skin lesions and the position of rank(P<0.05) in Large White piglets. The rank index of Minpig piglets was only positively correlated with weaning weight(P<0.05). There was the significant positive correlation between rank index of Large White piglets and weaning weight, relative growth rate and average daily gain(P<0.05). This showed that Minpig piglets had less agonistic behavior, stronger adaptability to new environment, and the reconstruction of social rank after weaning mixing had less influence on their growth performance, and it was more suitable for mixed breeding, compared with Large White piglets.