Profile of Maternally Derived Antibody in Broiler Chicks and In-Ovo Vaccination of Chick Embryo against Newcastle Disease

In this study, we determined the suitability of lentogenic LaSota and naturally occurring avirulent I2 vaccine strains of Newcastle disease (ND) virus for efficacious in-ovo vaccination of broiler chickens. A total of 114 embyonated eggs divided into five groups (A, B, C, D and E) consisting of 25 eggs in each of groups A and B, 20 eggs in each of groups C and D and 24 eggs in group E were used in the study. Eighteen-day-old embryonated eggs in group A were vaccinated in-ovo with ND-I2 vaccine while the same age of embryos in group B were vaccinated with ND-LaSota. Thirteen-day-old embryonated eggs in groups C and D were vaccinated with ND-I2 and ND-LaSota respectively. Group E served as unvaccinated control. There was significant difference (p 2) used for the in-ovo vaccination were pathogenic for chick embryos, however, ND-I2 vaccine was better tolerated when administered to 18-day-old chick embryo.

Nutritional stimulation by in-ovo feeding modulates cellular proliferation and differentiation in the small intestinal epithelium of chicks

Nutritional stimulation of the developing small intestine of chick embryos can be conducted by in-ovo feeding(IOF).We hypothesized that IOF of glutamine and leucine can enhance small intestinal development by promoting proliferation and differentiation of multipotent small intestinal epithelial cells.Broiler embryos(n=128)were subject to IOF of glutamine(IOF-Gln),leucine(IOF-Leu),NaCl(IOF-NaCl)or no injection(control)at embryonic d 17(E 17).Multipotent,progenitor and differentiated cells were located and quantified in the small intestinal epithelium between E 17 and d 7 after hatch(D 7)in all treatment groups by immunofluorescence of SRY-box transcription factor 9(Sox9)and proliferating cell nuclear antigen(PCNA),in-situ hybridization of leucine-rich repeat containing G-protein coupled receptor 5(Lgr5)and peptide transporter 1(PepT1)and histochemical goblet cell staining.The effects of IOF treatments at E 19(48 h post-IOF),in comparison to control embryos,were as follows:total cell counts increased by 40%,33%and 19%,and multipotent cell counts increased by 52%,50%and 38%,in IOF-Gln,IOF-Leu and IOF-NaCl embryos,respectively.Only IOF-Gln embryos exhibited a significance,36%increase in progenitor cell counts.All IOF treatments shifted Lgr5+ stem cell localizations to villus bottoms.The differentiated,PepT1+region of the villi was 1.9 and 1.3-fold longer in IOF-Gln and IOF-Leu embryos,respectively,while goblet cell densities decreased by 20%in IOF-Gln embryos.Postehatch,crypt and villi epithelial cell counts were significantly higher IOF-Gln chicks,compared to control chicks(P<0.05).We conclude IOF of glutamine stimulates small intestinal maturation and functionality during the peri-hatch period by promoting multipotent cell proliferation and differentiation,resulting in enhanced compartmentalization of multipotent and differentiated cell niches and expansions of the absorptive surface area.