Hatching method correlates to early growth in chickens but not later performance

On-farm hatching has emerged as an alternative to conventional hatchery practices, in order to improve chick welfare, early growth, and overall production efficiency by reducing stress associated with post-hatch handling and transport. This study investigated the interactive effects of hatching method and dietary hydrolyzed yeast inclusion on growth performance, organ development, protein digestibility, and litter quality in broiler chickens. A total of 1,680 mixed-sex chicks obtained from either on-farm or conventional hatching systems were offered one of three starter diets containing 0, 5, or 10 g/kg of hydrolyzed yeast. The experiment followed a 2 × 3 factorial design with eight replicates per treatment and 35 birds per replicate pen. Growth performance was monitored until day 39, and organ weights, protein digestibility, and litter parameters were assessed during the starter phase. On-farm hatched birds were significantly heavier at placement and day 14 (P < 0.01), with increased feed intake and feed conversion ratio (FCR) during the starter phase. However, these early advantages diminished by day 39, with no significant difference in final body weight or carcass yield. Apparent ileal protein digestibility was not impacted by hatching method but was the highest in birds offered diet containing 5 g/kg hydrolyzed yeast (P = 0.005). The body weight advantage of on-farm hatched birds was maintained until day 28 (P = 0.011) but disappeared by day 39 (P = 0.213). No significant effects were observed on relative organ weights at day 14, litter moisture and pH during the starter phase, footpad dermatitis and hock burns at day 38. The findings suggest that on-farm hatching improves early growth performance up to day 28 and may offer advantages for markets targeting smaller birds. Hydrolyzed yeast inclusion enhanced protein digestibility at day 14 but this did not translate into improved performance or carcass traits under the conditions tested. Further research is warranted to explore the potential benefits of hydrolyzed yeast in diets containing higher levels of poorly digestible protein ingredients, as well as the advantages of on-farm hatching under conditions of prolonged fasting and transportation stress.