Abstract
ABSTRACT To investigate the protective effect of glutamine (Gln) on lymphocyte proliferation and the intestinal mucosal immune response in heat-stressed broilers, 360 21-day-old Arbor Acres (AA) broilers were assigned to 4 groups in a completely randomized design, each of which included 6 replicates with 15 birds per replicate for 21 days. The chickens were fed a basal diet under no stress (NS group), a basal diet under heat stress (HT group), or a basal diet under heat stress with the addition of either 0.5 % or 1.0 % Gln. The results showed that the broilers in the HT group exhibited fewer proliferating peripheral lymphocytes, a lower growth performance, phagocytic rate and index of neutrophils, fewer goblet cells in whole intestine and intraepithelial lymphocyte (IEL) cells in the ileum, a lower sIgA content in the duodenum and the jejunum, a lower immunoglobulin content of serum and intestinal mucosa, than those of the NS group (p<0.05). Diets supplemented with Gln increased growth performance, the number of proliferating peripheral lymphocytes, the phagocytic rate and phagocytic index of neutrophils, the number of whole intestine goblet cells and ileum IEL cells, the sIgA contents of the duodenum and the jejunum, and the immunoglobulin contents of serum and intestinal mucosa (p<0.05) in broilers exposed to HT. In conclusion, Gln can enhance intestinal immune function in broiler chickens by stimulating T and B lymphocyte proliferation, increasing the number of goblet cells and IEL cells, as well as increasing the content of sIgA and immunoglobulin secretion.
Highlights
Heat stress is a stress response induced by high environmental temperature-relative humidity
The final weight, average daily gain (ADG), and average daily feed intake (ADFI) were significantly lower in the HT group than in the NS group, and feed/ gain ratio (F/G) were significantly higher in the HT group than in the NS group, (p
Fundamental immunological functions are provided by the intestinal mucosal immunity system, which is, in part, composed of gut-associated lymphoid tissue, intraepithelial lymphocyte (IEL), goblet cells (GC), and abundant immunoglobulins
Summary
Heat stress is a stress response induced by high environmental temperature-relative humidity. Many studies have evaluated the effects of biological barriers on intestinal permeability in heat stress animal models These studies show that high temperature can affect nutrient transportation and absorption (Baumgard & Rhoads, 2013), cause a significant decline in the number of lymphocytes and goblet cells in the jejunum (Quinteiro-Filho et al, 2015), and decrease the specific IgA (sIgA) antibody secretion contents of intestinal mucosa lymphatic tissue (Tsujita & Morimoto, 1999). Under these conditions, a functional imbalance of the immune system arises, eRBCA-2019-1207
Sign-in/Register to view highlights & summary 
Published Version (
Free)
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call