Hewett Eleanor, Zaragoza Luis, Lewis Craig, Houdijk Jos, Wilson Andrea, Turner Simon
Animal Behaviour and Welfare, Animal and Veterinary Sciences Department, Scotland's Rural College (SRUC), Edinburgh EH9 3JG, UK.
Global Research and Communication Manager, Pig Improvement Company (PIC), Hendersonville, TN, USA37075.
J Anim Sci. 2025 Jan 4;103. doi: 10.1093/jas/skaf030.
Negative social behaviors between pigs can cause stress, which can compromise welfare. There has been significant interest in exploring the effect of diet on negative social behaviors and the wider social behavior repertoire of pigs. The aim of this study was to determine the effects of dietary Lysine (Lys) and Tryptophan (Trp) levels on the social behavior of commercially housed pigs. A total of 2,293 PIC Camborough barrows with a mean starting weight of 11.87 ± 1.35 kg were used in a randomized complete block design with a 2 × 3 factorial arrangement, with 16 replicates per treatment, of the following factors: 1) Standardized ileal digestible Lys levels: 100% Lys = diets with 100% PIC requirement at the midpoint of the growth phase (Lys 100) vs 80% Lys = diets with 80% PIC requirement at the midpoint of the growth phase (Lys 80); and 2) Trp to Lys ratio of 0.210, 0.185, or 0.160. Pigs were randomly allocated across the 6 treatments over 2 starting dates. Behavior and lesion data were collected. There was an effect of Lys (P = 0.032) on ear-biting behavior, with pigs on the Lys 80 treatments showing a higher level of ear-biting behavior. We also found an effect of the Lys score week interaction on the proportion of pens showing ear lesions (P < 0.001) and an effect of the Lys Trp interaction (P = 0.030) and the Lys score week interaction (P = 0.0104) on the proportion of pens showing severe ear lesions. In conclusion, the lysine content of feed can affect the social behavior of pigs, specifically ear biting, in commercial conditions.
猪之间的负面社交行为会导致压力，进而可能损害其福利。人们对探索饮食对猪的负面社交行为以及更广泛的社交行为模式的影响产生了浓厚兴趣。本研究的目的是确定日粮赖氨酸（Lys）和色氨酸（Trp）水平对商业饲养猪社交行为的影响。总共2293头平均初始体重为11.87±1.35千克的PIC坎布罗公猪被用于随机完全区组设计，采用2×3析因安排，每个处理有16个重复，涉及以下因素：1）标准回肠可消化赖氨酸水平：100% Lys = 在生长阶段中期满足100% PIC需求的日粮（Lys 100），而80% Lys = 在生长阶段中期满足80% PIC需求的日粮（Lys 80）；2）Trp与Lys的比例为0.210、0.185或0.160。猪在两个起始日期随机分配到6种处理中。收集了行为和损伤数据。赖氨酸对咬耳行为有影响（P = 0.032），Lys 80处理的猪表现出更高水平的咬耳行为。我们还发现赖氨酸评分周交互作用对出现耳部损伤的栏舍比例有影响（P < 0.001），赖氨酸与色氨酸交互作用（P = 0.030）和赖氨酸评分周交互作用（P = 0.0104）对出现严重耳部损伤的栏舍比例有影响。总之，在商业条件下，饲料中的赖氨酸含量会影响猪的社交行为，特别是咬耳行为。
