Raihan Said Majdood, Tsudzuki Masaoki, Kawakami Shin-Ichi
Graduate School of Biosphere Science, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8528, Japan.
Japanese Avian Bioresource Project Research Center, Hiroshima University, Higashi-Hiroshima, Hiroshima 739-8528, Japan.
J Poult Sci. 2017 Oct 25;54(4):296-302. doi: 10.2141/jpsa.0170028.
Chicken agonistic behavior, a type of social behavior related to threatening and fighting, is among the most serious problems in the poultry industry. However, due to luck of effective models for investigating the brain mechanisms of the behavior, no effective measures have been taken. This study, therefore, aimed to select the behavioral tests available for monitoring chicken agonistic behavior. Two behavioral tests, resident-intruder (R-I) test and social interaction (SI) test, were performed for 10 minutes in 10 pairs of male layer chicks at 8, 12, 16, 20, and 24 days of age, and total agonistic frequencies (TAF: Sum of the frequencies of agonistic displays like pecking, biting, kicking, threatening, and leaping) and latency (the period of time from the beginning of the behavioral test to the occurrence of the first agonistic behavior) were measured as indices of agonistic behavior. Two-way repeated measures ANOVA revealed significant differences in TAF and latency between aggressors and opponents in both the behavioral tests. In the R-I test, the TAF of aggressors significantly increased from 8 to 20 days of age, and the latency significantly decreased from 8 to 24 days of age. In the SI test, however, the TAF of aggressors significantly increased and the latency significantly decreased only from 16 to 20 days of age. When the criterion of high agonistic behavior was defined as the TAF, where aggressors showed more than 30 times of TAF and the opponents did less than one-third TAF of aggressors, the aggression establishment rate (AER), which is equal to the number of aggressors showing high agonistic behavior per total behavioral trials, was significantly higher in the R-I test than in the SI test. These results suggest that the R-I test, rather than the SI test, is an effective tool for monitoring agonistic behavior of layer chicks.
鸡的争斗行为是一种与威胁和打斗相关的社会行为，是家禽业中最严重的问题之一。然而，由于缺乏用于研究该行为脑机制的有效模型，尚未采取有效的措施。因此，本研究旨在选择可用于监测鸡争斗行为的行为测试。对10对8日龄、12日龄、16日龄、20日龄和24日龄的雄性蛋鸡雏进行了两项行为测试，即定居者-入侵者（R-I）测试和社交互动（SI）测试，每次测试10分钟，并测量总争斗频率（TAF：啄、咬、踢、威胁和跳跃等争斗表现的频率总和）和潜伏期（从行为测试开始到首次出现争斗行为的时间段）作为争斗行为的指标。双向重复测量方差分析显示，在两项行为测试中，攻击者和对手之间的TAF和潜伏期存在显著差异。在R-I测试中，攻击者的TAF从8日龄到20日龄显著增加，潜伏期从8日龄到24日龄显著缩短。然而，在SI测试中，攻击者的TAF仅在16日龄到20日龄显著增加，潜伏期显著缩短。当将高争斗行为的标准定义为TAF时，即攻击者的TAF超过30次且对手的TAF少于攻击者的三分之一，攻击确立率（AER，等于在总行为试验中表现出高争斗行为的攻击者数量）在R-I测试中显著高于SI测试。这些结果表明，R-I测试而非SI测试是监测蛋鸡雏争斗行为的有效工具。
