Behavioural Variability in Chicks vs. the Pattern of Behaviour in Adult Hens
Institute of Biological Basis of Animal Production, University of Life Sciences in Lublin, Akademicka 13, 20-950 Lublin, Poland
Author to whom correspondence should be addressed.
Received: 22 December 2019 / Revised: 5 February 2020 / Accepted: 6 February 2020 / Published: 9 February 2020
Environmental requirements ensuring behavioural welfare to laying hens may vary depending on the breed. Chickens representing various breeds and reared in the same environment were found not only to differ in the level of activity, emotional arousal, and degree of curiosity, but also to prefer different enrichments of the environment, which was reflected by different levels of stress in these birds. Hence, a question was posed whether the behavioural differences observed were innate behavioural patterns typical of the breed or whether they are an effect of the modifying impact of the environment, which varies between breeds. It has been hypothesised that differences observed already in chicks of different breeds may not be associated with the modifying effect of the environment. Instead, they may be a genetically determined breed-specific behaviour. The present investigations consisted in behavioural tests and assessment of the behaviour of chicks of three laying hen breeds. The study involved 60 green-legged partridge (Zk), 60 Polbar (Pb), and 60 Leghorn (Lg) chicks. The investigations have demonstrated that the birds from the analysed breeds exhibit behavioural differences already on the first days of life. The effect of the breed was evident in the case of such traits as strategy for acquisition of food resources, fearfulness/curiosity, and interest in elements of the environment. With age, chicks may exhibit changes in their emotions, e.g., more pronounced fearfulness, and environmental preferences. However, in the latter case, there is clear tendency towards breed-specific behaviours exhibited from the first days of life. The level of activity, which largely differentiates adult birds, does not discriminate between chicks.