Parental Age is not a Decisive Factor Influencing Gut Development, Nutrient Utilization, or Growth Performance in...

Progeny from older breeder hens exhibit higher feed intake but less efficient nutrient utilization than those from younger breeders. Multi-enzyme supplementation (MES) can serve as a practical dietary intervention to address this challenge. This study aimed to assess the effect of broiler breeder hen age (BBA) and MES on growth performance, gastrointestinal tract traits, nutrient digestibility, and cecal microflora profile of broilers. A total of 780 one-day-old straight-run Ross 308 chicks were arranged in a 2 × 3 factorial design according to two breeder ages (39 or 60 weeks) and three types of diet: a basal diet (CNT), basal diet supplemented with a commercial multi-enzyme product (AVZ, or Avizyme 1500^®), and a laboratory-formulated multi-enzyme preparation (LTE). Each treatment group consisted of five replicates with 26 birds. No significant interaction was observed between BBA and MES for any of the studied variables. Neither MES nor BBA influenced any growth performance trait. However, from days 28 to 42, the offspring of older parents showed an increased feed intake (P < 0.05). On day 9, MES lowered pancreatic weight (P < 0.05), pancreatic amylase activity (P < 0.01), and sulfite-reducing anaerobic bacteria in the cecum compared to the CNT treatment. Additionally, on days 9 and 42, LTE supplementation reduced (P < 0.01) pancreatic lipase activity and improved (P < 0.05) the digestibility of ether extract. The present results indicate that, when diets are formulated to meet or approach the nutritional requirements, chickens may not derive substantial additional benefits from AVZ or LTE supplementation. This may explain the absence of the anticipated interaction between BBA and MES.