Turkey Breeder Hen Age Affects Growth and Systemic and Intestinal Inflammatory Responses in Female Poults Examined at Different Ages Posthatch

Abstract

This trial examined the effect of 2 turkey breeder hen ages (33 or 55 wk of age) on performance, intestinal histology, and inflammatory immune response of female turkey poults grown to market weight. Using a randomized design, female poults were separated by breeder flock age (n = 8 floor pens/breeder flock age; n = 26 poults/pen; 0.195 m(2)/bird), fed identical commercial diets (9 phases), and grown to market weight (approximately 11.4 kg/ bird). At young ages, poults from the older breeder flock tended to have higher BW (P < 0.01 for d 7, P < 0.09 for d 63), although feed consumed was not significantly different due to breeder flock age (P > 0.20 for all ages). After approximately 63 d posthatch, no difference in BW was observed, suggesting that poults from the younger breeder flock were eventually able to compensate for initial reductions in performance. In addition to growth measurements on d 10, 24, and 65 posthatch, poults were vaccinated with lipopolysaccharide (LPS, from Salmonella Typhimurium; 0.5 mg/kg of BW intraabdominally) or not vaccinated (control), and intestinal histology and plasma haptoglobin were assessed at 24 h postadministration. In control birds, intestinal villus length was greater for poults from the older breeder flock (P < 0.05), as was crypt depth (P < 0.05 for d 11 and 25). Plasma haptoglobin levels did not change in 11-d-old poults after LPS administration, but they increased with LPS at d 25 and 66 posthatch (P < 0.05 for each). At d 66 posthatch, poults from the younger flock had increased haptoglobin levels post-LPS compared with those from the older breeder flock (P < 0.05). In general, LPS administration increased villus width in the jejunum and ileum (P < 0.05 for each), increased lamina propria width in the duodenum and ileum (P < 0.05 for each), and decreased ileum crypt depth (P < 0.05). Overall, poults from the older breeder flock had reduced inflammatory responses, even at 9 to 10 wk posthatch, even though performance was similar in poults from the 2 flocks by this age.