Effect of transport duration and parental age on day-old chick welfare and performance

Most broiler chicks are transported to production sites within 1-2 days post-hatch, which may cause stress, and compromise welfare and productivity. The impact of transport is poorly understood, and could vary between chicks from flocks of breeders of different ages. Therefore, we aimed to investigate the effect of transport duration and breeder age on chick welfare and productivity. Mixed-sex chicks from either 29-wk-old or 60-wk-old Ross 308 breeders were bred in a commercial hatchery. After hatch, 1620 chicks from young and 1620 chicks from old breeders were transported in 36 crates. Eighteen crates were subjected to a 1.5h or 11h road transport. After transport, 2800 chicks were placed in 100 pens (2m2), each containing 28 chicks from one transport crate. On average six chicks were randomly selected per crate (n=228) and assessed for chick quality, weighed and culled to weigh yolk sacs (d1 at farm). Mortality and feed conversion of the remaining chicks were recorded until slaughter (41d of age). No transport x breeder age interaction effects were found. Body and yolk sac weight at d1 were lower for chicks transported for 11h compared to 1.5h (body: 42.3g vs 43.7g; P=0.003; yolk: 3.9g vs 5.2g; P<0.001) and for chicks from young versus old breeders (body:38.4g vs 47.6g; P<0.001; yolk: 3.4g vs 5.7g; P<0.001). This effect of breeder age on body weight persisted until slaughter (2.5kg vs 2.7kg; P<0.001). Chick quality (89.1% vs 92.7%; P=0.001) and feed conversion during d0-14 (1.40 vs 1.47; P=0.048) were lower in chicks from old versus young breeders, but were unaffected by transport duration. Mortality was not affected by either factor. The study did not confirm any interactive effects of transport duration and breeder flock age. Long transport negatively affected d1-yolk and body weight, chicks from old breeders showed reduced quality, slaughter weight and feed conversion.