Broilers (<i>Gallus gallus</i>) are less stressed if they can smell a mother odorant

Abstract

Performance, physiological and behavioural parameters of two groups of domestic chickens were compared. Chickens were raised in classical commercial conditions in buildings housing 12000 birds. One group acted as a control, while the environment of the other was perfused with MHUSA (Mother Hens' Uropygial Secretion Analogue), a synthetic analogue of a mother-hen odorant secretion which has shown its potential in reducing stress-related reactions in chickens. At the end of the rearing period the animals treated, appeared less stressed, as determined by a range of behavioural and physiological parameters. Even if there was no treatment effect on live weight, the carcasses of MHUSA treated animals were heavier and showed less scarring from fights. The influence of MHUSA was proven when it was removed from the atmosphere. Sex and age appeared to have an importance with regard to the action of MHUSA on the number of suffocated animals. There were no differences between the two groups in a variant of the tonic immobility test. Thus this semiochemical appears to have a positive effect on broiler welfare. Keywords: Broilers, welfare, behaviour, physiology, semiochemicalSouth African Journal of Animal Science Vol. 38 (3) 2008: pp. 201-206