Strain and age differences in behaviour, fear response and pecking tendency in laying hens

Abstract

1. Behaviours associated with a high or low tendency to feather peck could be used as predictors of feather pecking behaviour in selective breeding programmes. This study investigated how strain and age at testing influenced responses in behavioural tests. 2. Four layer-type strains (ISA Brown, Columbian Blacktail, Ixworth and a high feather pecking (HP) and a low feather pecking (LP) line of White Leghorn) were reared in 6 same-strain/line pens of 8 birds from one day old. Birds in half the pens were given an open field test, a novel object test and a test with loose feather bundles between 4 and 12 weeks of age and a tonic immobility (TI) test at 13 weeks of age. All pens were tested with fixed feather bundles at 26 weeks, and undisturbed behaviour in the home pens was videoed at 1 and 27 weeks of age. Daily records of plumage damage were used as an indicator of feather pecking activity in the home pens. 3. Strain did not influence novel object test, open field test or loose feather test behaviour, although age effects in all three tests indicated a reduction in fearfulness and/or an increase in exploratory behaviour with increasing age. 4. White Leghorns showed longer TI durations than the other strains but less pecking at fixed feather bundles than ISA Browns and Columbian Blacktails. 5. There were few associations between behaviour in the 5 different tests, indicating that birds did not have overall behavioural traits that were consistent across different contexts. This suggests hens cannot easily be categorised into different behavioural 'types', based on their test responses and casts doubt on the usefulness of tests as predictors of feather pecking.

Brain gene expression in relation to fearfulness in female red junglefowl (Gallus gallus)

“…The PCA showed a relatively coherent set of correlated behaviors across the different fear tests in a first component. Although only a limited fraction of the variation was explained, the component corresponds relatively well to what other studies have found using multivariate analysis, including our own earlier research (Albentosa et al 2003; Burns et al 1998; Campler et al 2009; Forkman et al 2007). We therefore assume that this component represents a general fearfulness trait, which can be assessed on individual level.…”

Short Copy Number Variations Potentially Associated with Tonic Immobility Responses in Newly Hatched Chicks

“…WL chicks were prone to be induced into the TI status with fewer attempts (low TI ind ), whereas NG had longer TI dur in each successful TI induction. These empirical data strongly support the previous hypothesis that the TI behavior in chickens has a genetic basis with breed- or strain-specific behavioral characteristics [8], [25], [26].…”

Can Non-Beak Treated Hens be Kept in Commercial Furnished Cages? Exploring the Effects of Strain and Extra Environmental Enrichment on Behaviour, Feather Cover, and Mortality

“…In addition, management techniques to reduce IP that work for Lohmanns (e.g., reducing light intensity) may not be practical for Hylines as this has had previous detrimental effects for productivity in this particular farm (C Kirk, personal communications). The extent to which the management affected the outcome variables is uncertain, as inherent breed differences have been reported to exist in other research, with significant differences in overall activity levels as well as feather pecking behaviour [ 36 ]. Not only do commercially available breeds behave differently, but there is evidence to suggest that feather pecking is a heritable trait [ 37 ], as two divergent lines with different propensities for feather pecking have been developed in recent years [ 9 , 38 ].…”