Effects of Glucomannan Feed Additives on Large White Turkey Female Performance, Gastrointestinal Microbial Population, and Blood Corticosterone Levels in a Simulated Transport Challenge

Abstract

Turkeys may experience stress due to conditions of transport, heat, and in some cases, feed and water restrictions. This may include experiencing conditions present when female turkeys are transported from the brooder house to the grow-out house, typically at 4 to 5 wk of age. This study’s objective was to determine the effect of glucomannan feed additives on performance and corticosterone response in Large White commercial females after an application of simulated conditions which birds might experience during transportation at 4 to 5 wk of age. The transport simulation consisted of reducing the space per bird from 0.198 m2 /bird to 0.028m2 /bird, with no food and water, and exposed to heat lamps, for no more than 18 h. Fourteen hundred and forty Large White female turkeys were randomly assigned to 48 concrete, pine shavings covered floor pens. The experimental design was a completely randomized block design with a one-factor arrangement of 2 sources of glucomannans (medium-chain and long-chain) with two inclusion levels of each (0.02 and 0.20% of the diet). These treatments were compared to two control treatments (no glucomannans), however, one with no simulated transport conditions and one exposed to simulated transport conditions. Bird’s performance, bursa, spleen, and blood corticosterone levels were analyzed in SAS 9.4 in a mixed model. No effects on growth performance of birds fed 0.02% glucomannans were observed. Birds fed glucomannans at 0.20% in the diet had a higher corticosterone level after the transport simulation was applied when compared to other treatments. However, birds fed medium-chain glucomannans at 0.20% had an improved performance after the transport simulation compared to birds fed the other glucomannan treatments. All birds recuperated their performance by d 45. No differences were found in the spleen and bursa weights at 45 d of age. Both glucomannans reduced the stress impact on intestinal bacteria by controlling the overgrowth of Lactobacillus and Fusobacteria while maintaining Bacteroidetes. In conclusion, glucomannans can be used in diets with no change in performance or health at 45 d of age while preserving intestinal microbiota from the negative effects of stress. At 45d, all birds recuperated from the simulated transport conditions applied at 29 d. Thus, the effects of glucomannans on turkey performance and health should be further investigated.