On-farm hatching can improve welfare, chicks quality, breast yield and daily body weight gain
Résumé
On-farm chick hatching is significantly growing in many European countries. Three days before hatching, eggs are transferred from a hatchery to the farm, allowing chicks to access feed and water while avoiding the perturbations generated by sorting, sexing, vaccination and transportation. Despite real benefits of this practice in terms of welfare, its long-term impacts on zootechnical criteria and meat quality when different types of barn heaters are used. This study proposes a multi-criteria evaluation of Ross 308 broiler production with two different heating systems (radiant heating system or gas cannon heater) compared with conventional hatching and two pre-incubation storage durations for eggs (5d vs. 15d). Chick quality, as evaluated based on Tona score, was improved for chicks hatched on-farm compared to chicks from the experimental hatchery. Behavioural and health indicators were collected by observation of the animals (adapted EBENE®) method). No impact of heating system or pre-incubation storage duration on the occurrence or severity of pododermatitis, on the number of lame, dirty and nervous broilers, or on pecking, grooming, exploring and resting behaviour. Regarding zootechnical values, average daily body weight gain was higher (+3 g/d) for on-farm hatched group resulting in a difference of 100–120g/broiler at slaughter age compared to controls. Breast yield followed this trend by showing +0.4 points on average. Feed conversion ratio as well as meat quality indicators (fat percentage, colour, breast defects) remained unchanged. Eggs stored for 15 days pre-incubation were negatively impacted on embryo mortality, hatching rate, mortality on farm, duration of the hatching window (37h vs. 29h with short storage) independently of the hatching practice. This study demonstrates that on-farm hatching, although improving broiler welfare, can also show zootechnical and economical benefits. However, results reveal that hatching temperature must be well controlled, to avoid temporal and spatial fluctuation, especially for long-stored eggs.