Different concentrations and sources of dietary fibre may improve the welfare of female broiler breeders.

1. Broiler breeder females were fed restricted allocations of food to meet target body weights. They were fed on a standard wheat-soy ration or on one of three series of rations containing 50, 100 or 200 g/kg of ground oat hulls, ground unmolassed sugar beet pulp or sunflower meal. Changes in behaviour and heterophil-lymphocyte ratio (HLR) were measured at 5, 10 and 15 weeks of age. 2. Body weight at 15 weeks of age decreased in a linear manner with increasing concentrations of the experimental ingredients. 3. Decreased spot pecking was observed in birds fed on the rations containing 50 g/kg of sugar beet pulp and 200 g/kg of oat hulls. 4. The HLR was higher in birds fed on the control diet and diets containing 50 g/kg of the high fibre ingredients. 5. Rations containing sugar beet pulp were associated with higher water contents in the gastrointestinal tract and it is proposed that this improved satiety and welfare.

Genotype, dietary manipulation and food allocation affect indices of welfare in broiler breeders.

1. An experiment was performed to compare the welfare of three broiler breeder genotypes (Label Rouge (LA), experimental dwarf (ER) and standard (SR)) fed on a Control or high Fibre diet. The LA birds were fed ad libitum and the other groups were reared to their recommended body weight targets. A group of standard broiler breeders was also fed a restricted amount of food, but to a lesser degree than SR, to achieve the same proportion of body weight (SE) as ER relative to ad libitum-fed dwarfs based on previous research. LA, ER, SR and SE are referred to as 'groups' in the text. 2. Welfare was assessed by comparing time budgets and heterophil-lymphocyte ratios (HL ratios) at 5, 10 and 15 weeks and immune responses at 15 weeks of age. In addition the weight and water content of the gastrointestinal tract at 4-h intervals at the end of the experiment were studied in LA and SR fed on both diets. 3. Body weights of LA, ER and SR fed on the Fibre diets were depressed and LA ate less of the Fibre than the Control diet. The coefficient of variation of body weight at 15 weeks was 7.9% in LA and similar (10.8 to 11.6%) in the other groups. 4. Drinking, litter-directed behaviour, resting and standing were affected by a group x age interaction with restricted birds showing increased drinking over time and less time spent resting compared to LA. The behaviour of ER birds was similar to SE. 5. HL ratios were within the normal biological range although all restricted-fed birds had an elevated HL ratio at 10 weeks of age relative to week 5 whereas LA birds had a reduced HL ratio at 15 weeks relative to 5 and 10 weeks of age. Immune responses were lower in ER and SE and the highest response was in SR. 6. No effects of diet were identified on behaviour, white blood cell counts or HL ratio. 7. With the exception of the crop, the dry weights of digesta in each section of the gut were similar in LA and SR birds. The results suggest that drinker-directed activity might be a substitute for foraging rather than an attempt to increase gut fill. 8. It is concluded that the replacement of standard with dwarf broiler breeders may improve the welfare of commercial flocks of broiler breeders by decreasing the degree of food restriction resulting in favourable changes in behaviour, for example, reduced 'drinker-directed' behaviour.