In ovo and Dietary Supplementation of Probiotics Affects Post-Hatch Expression of Immune-Related Genes in Broiler Chicks

Abstract

During the first week post-hatch, the neonatal chick is immunologically vulnerable and subject to infectious threats found in the environment. Probiotics are live, non-pathogenic microorganisms known to have a positive effect on the host by improving the natural balance of gut microbiota and promoting animal health. The objective of this study was to determine the effects of administering probiotics in ovo and in the diet on broiler chick hatchability, and post-hatch immune organ weights and ileal immune-related gene expression. At embryonic day 18, 1584 eggs were injected with nothing (Dry), 1 × 10 6 , or 1 × 10 7 (P1 and P2 respectively) probiotic bacteria. The remaining 393 eggs were left non-injected to serve as a negative control. Immune organ weights and tissue samples were taken on DOH and d4, 6, 8, 14, and 20. No differences were observed for hatchability or relative bursa weights. Only on d6, the P2 birds receiving the probiotic-supplemented diet had larger spleens as a result of a 2-way interaction between in ovo treatment and post-hatch diet. Both in ovo and dietary administration of probiotics were able to modulate the expression of the immune-related genes in the ileum; however, expression patterns differed based on the gene, treatment, and time point evaluated. In conclusion, these results indicate that in ovo supplementation of this commercial probiotic product does not influence hatchability and is capable of differentially modulating expression of certain genes in the ileum. Furthermore, in ovo administration of probiotics has an effect similar to that of dietary supplementation endorsing its usage to potentially promote early colonization of beneficial bacteria to stimulate intestinal and immune system development.

Effect of in ovo feeding of probiotic, prebiotic and synbiotic to Broiler embryos on growth performance, Mucin-2 gene expression and gut colonization of microbiota

“…Whereas, Mucin-2 gene expression was not affected in other parts of small intestinal. Pender et al (2017a), who found that in ovo inoculation of commercial probiotic at different doses (1×10 5 , 1×10 6 and 1×10 7 cfu) did not affect the expression level of Mucin-2 gene in the ileum of broilers on 4 th , 6 th , 8 th , 15 th and 22 nd day age was contrary to the present finding.…”

Necrotic Enteritis in Broiler Chickens: The Role of Tight Junctions and Mucosal Immune Responses in Alleviating the Effect of the Disease

“…Birds were assigned to one of the three dietary treatments (12 pens/treatment) as follows: Negative Control (NC): corn-soybean meal basal diet (Table 1); Positive control (PC): NC + 20 mg virginiamycin/kg (as 0.450 kg Stafac ® 20) diet from d 0–42; Probiotic: NC + PrimaLac (1.36 kg/ton in the starter and grower 1 diets; 0.91 kg/ton in grower 2 and finisher diets). PrimaLac contains Lactobacillus acidophilus , Lactobacillus casei , Bifidobacterium bifidum , and Enterococcus faecium [22]. All animal protocols were approved and conducted under the guidelines of the Virginia Tech Institutional Animal Care and Use Committee (IACUC # 18-011).…”

“…Average gene expression relative to GAPDH for each sample was calculated using the 2 −ΔΔCt method [24]. The calibrator for each gene was the average ΔCt value from the negative control group [22].…”