In ovo Feeding as a Tool for Improving Performance and Gut Health of Poultry: A Review

Abstract

Early growth and development of the gastrointestinal tract are of critical importance to enhance nutrients' utilization and optimize the growth of poultry. In the current production system, chicks do not have access to feed for about 48–72 h during transportation between hatchery and production farms. This lag time affects early nutrient intake, natural exposure to the microbiome, and the initiation of beneficial stimulation of the immune system of chicks. In ovo feeding can provide early nutrients and additives to embryos, stimulate gut microflora, and mitigate the adverse effects of starvation during pre-and post-hatch periods. Depending on the interests, the compounds are delivered to the embryo either around day 12 or 17 to 18 of incubation and via air sac or amnion. In ovo applications of bioactive compounds like vaccines, nutrients, antibiotics, prebiotics, probiotics, synbiotics, creatine, follistatin, L-carnitine, CpG oligodeoxynucleotide, growth hormone, polyclonal antimyostatin antibody, peptide YY, and insulin-like growth factor-1 have been studied. These compounds affect hatchability, body weight at hatch, physiological functions, immune responses, gut morphology, gut microbiome, production performance, and overall health of birds. However, the route, dose, method, and time of in ovo injection and host factors can cause variation, and thereby inconsistencies in results. Studies using this method have manifested the benefits of injection of different single bioactive compounds. But for excelling in poultry production, researchers should precisely know the proper route and time of injection, optimum dose, and effective combination of different compounds. This review paper will provide an insight into current practices and available findings related to in ovo feeding on performance and health parameters of poultry, along with challenges and future perspectives of this technique.

Managing Gut Microbiota through In Ovo Nutrition Influences Early-Life Programming in Broiler Chickens

“…Prebiotics and probiotic microorganisms used together help produce synbiotics, which provide advantages superior to those of prebiotics or probiotics on their own. In ovo delivery of some commercial prebiotic (extract of beta-glucans and transgalactooligosaccharides) significantly increased Bifidobacteriaceae and Lactobacillus count in feces of broiler chicks on the day of hatching [97]. Pacifici et al [149] demonstrated that stachyose and raffinose enhanced gut health through improving the growth of beneficial bacteria and preventing the abundance of potentially pathogens.…”

“…During this time, all ecological microbes, including commensals and pathogens, would have an equal opportunity to occupy GIT [ 47 ]. Furthermore, early intervention strategies using commercial probiotics, prebiotics, or their combination (synbiotics) can help modulate the gut microbiota to prevent the colonization of pathogens and enhance the immune system and intestinal development [ 13 , 22 , 97 , 98 ].…”

“…Bioactive substances injected into the air cell can be transferred into the circulatory system via the highly vascularized chorioallantoic membrane. The embryo orally swallows those injected into the amniotic fluid during the late embryonic development before internal piping [ 97 , 113 , 114 ]. In ovo injection in the air cell is safe and recommended for several bioactive substances.…”

“…They found no effects of the treatments on the body weight and feed consumption [ 146 ]. In ovo delivery of a commercial prebiotic (extract of beta-glucans, trans-galactooligosaccharides) and raffinose family oligosaccharides significantly improved body weight gain compared to the control group, particularly throughout the first three weeks [ 97 ].…”

“…Moreover, prebiotics increased the feed intake and the feed conversion ratio. Injection of this prebiotics in ovo followed by the water administration did not reveal a synergistic effect on broiler performance compared to the in ovo injection alone [ 97 ]. Hence, these authors proposed that prebiotic administration through in ovo method can substitute the extended and expensive administration of the bioactive substances post-hatching through drinking water [ 97 ].…”