Effects of in ovo feeding of N-acetyl-L-glutamate on early intestinal development and growth performance in broiler chickens

• Published in: Poultry science Vol. 99; no. 7; pp. 3583 - 3593
• Main Authors: Wang, Jiguang, Lin, Jing, Wang, Jing, Wu, Shugeng, Qi, Guanghai, Zhang, Haijun, Song, Zhigang
• Format: Journal Article
• Language: English
• Published: England Elsevier Inc 01.07.2020; Elsevier
• Subjects: absorption; amino acid transporters; Animal Feed - analysis; Animals; chickens; Chickens - anatomy & histology; Chickens - growth & development; Chickens - physiology; Diet - veterinary; Dietary Supplements - analysis; Dose-Response Relationship, Drug; duodenum; eggs; feed conversion; feed intake; gene expression; Glutamates - administration & dosage; Glutamates - metabolism; growth performance; ileum; intestinal development; intestinal morphology; Intestines - anatomy & histology; Intestines - drug effects; Intestines - growth & development; Intestines - physiology; jejunum; Metabolism and Nutrition; N-acetyl-L-glutamate; nutrient transporter; Ovum - physiology; peptide transporters; Random Allocation; villi; growth performance; intestinal development; nutrient transporter; intestinal morphology; N-acetyl-L-glutamate
• ISSN: 0032-5791; 1525-3171; 1525-3171
• DOI: 10.1016/j.psj.2020.04.003

The present study determined the effects of in ovo feeding (IOF) of N-acetyl-L-glutamate (NAG) on early intestinal development and growth performance of broilers. A total of 702 fertile broiler eggs were randomly divided into 3 treatments: 1) non-punctured control group, 2) saline-injected control group, and 3) NAG solution–injected group (1.5 mg/egg). At 17.5 D of incubation, 300 μL of each solution was injected into each egg of injected groups. Results indicated that the hatchability and healthy chicken rate were not affected by NAG injection (P > 0.05). Chicks from NAG solution–injected group had significantly decreased average daily feed intake and feed conversion ratio during 1–14 D than those in the non-punctured control group (P < 0.05). Compared with the non-punctured control group, IOF of NAG significantly increased the density of goblet cells in jejunum at hatch, duodenum at 7 D, and ileum at 14 D; decreased crypt depth in jejunum at hatch; and increased villus height in duodenum and jejunum and villus height:crypt depth ratio in duodenum at 7 D (P < 0.05). The intestinal mRNA expression of Na+-dependent neutral amino acid transporter, peptide transporter, and excitatory amino acid transporter 3 did not differ between groups at 7 or 14 D. However, the mRNA expression level of rBAT in jejunum significantly increased in the NAG solution–injected group than in the non-punctured control group at 7 D (P < 0.05). In conclusion, IOF of NAG (1.5 mg/egg) accelerated the early intestinal development by enhancing intestinal immune and absorption function, thereby positively affecting the feed efficiency for the first 2 wk post-hatch.