Genetics of the Novel Object Test outcome in laying hens

Behavioural Variability in Chicks vs. the Pattern of Behaviour in Adult Hens

“…The present study also confirms that fearfulness is one of the temperament traits differentiating the breeds from the first days of life (Table 6). This trait in animals is characterised by a high inheritance rate, which has also been confirmed in laying hens [6,7]. The study has shown that fearfulness changes over time, exhibiting a downward trend in older chicks, which may be associated with habituation to a given stimulus.…”

“…As demonstrated in many studies, the level of additive variability is so high that selection for modification of chicken's temperament may bring positive effects [6,7,12]. Currently, behavioural selection is mainly targeted at reduction of aggression and pterophagy [13,14].…”

“…Since the behavioural patterns depend on the genetic background, previous bird's experiences, environmental conditions prevailing during embryonic development, and epigenetic effects [4,[6][7][8][9], a question was posed whether the differences observed in the behaviour of the three breeds (Zk, Lg, Pb) were innate breed-specific behavioural patterns or whether they were "generated" by their living environment. In other words, the question was whether the rearing practice, which was not adjusted to the genetic predisposition of the breed, was the cause of the behavioural differences or whether the breed-specific differences occurred regardless of the rearing practices.…”

Analysis of Behavioural Profile of Hens with the Use of Computer Software

“…On the basis of our previous studies (Rozempolska-Rucinska et al, 2017) all hens were classified according to their behaviour, to the one of 6 groups: escape (34 individuals)-birds with sudden movements, attempting to go outside the cage; avoidance (35 individuals)-birds moving away from the object but without sudden movements; avoidance-approach (35 individuals)-birds with alternate reactions: approach and moving away from the object; observation (44 individuals)-birds standing in one position with minor head or torso movements, observing the object and not approaching nor distinctly moving away from the object; approach (23 individuals)-approaching to the object, heading towards the object and observing it; pecking (29 individuals)-approaching to the object with one or multiple pecking on the object. Detailed information on the test performance and classification of laying hens to a specified group was given by Rozempolska et al, 2017aRozempolska et al, , 2017b The next step was the analysis of behavioural reactions with the use of Java-based free software, Tracker 4.95 ® (Brown, 2012) for motion analysis allowing determination of multiple movement parameters. Each video clip was analysed with a frame-by-frame method with step size of 20 frames which refers to an interval of 0.8 second.…”

“…On the other hand, it is possible to evaluate bird behavioural profile ( Table 3). Regarding that statistically significant differences of the results were found, the birds were classified into two behavioural profiles according to Rozempolska-Rucinska et al (2017a, 2017b. Hens manifesting reactions such as escape, avoidance, avoidance-approach were defined as timid birds, on the other hand, the profile of curious/ courageous hens included birds that were observing, approaching and pecking the object.…”