Effect of in ovo feeding on morphometric parameters of the intestinal tract and postnatal development of egg-bearing chickens

Abstract

Goal. To study the effect of in ovo feeding on postnatal development indicators of egg-bearing chickens. Methods. Studies on poultry were carried out following the standards of its breeding, maintenance, and feeding. Methods of physicochemical and biochemical analysis, as well as morphological and embryological methods were used, and biological control was carried out during incubation. Results. It was found that the chickens of experimental group 1, to which the carbohydrate component was added in ovo, during the first 4 weeks of growing had preservation rates 4.2% higher, and the chickens of group 2, to which the probiotic component was added, 2.8% higher compared to the chickens of the control group. At the end of the observation period, the preservation of chickens in the experimental groups remained 1.4% higher than in the control. Carbohydrates additionally obtained by group 1 chickens before hatching had a positive effect on their live weight, but a noticeable weight advantage of experimental chickens was observed only during the first 2 weeks. At 17 weeks of age, the weight of the chickens of experimental group 1 was 62.3 g greater than that of the control group. As for the chickens of experimental group 2, a steady increase in weight was observed from the 8th to the 17th week of growing, and at the end of the study period, their superiority over the control was 108,6 g. Given the results of hematological studies, it can be assumed that the chickens of experimental group 2 were in a better physiological state and had greater resistance against diseases compared to the chickens of control and experimental group 1. Evaluation of indicators of intestinal development and internal organs showed the superiority of the young birds of the experimental groups, primarily of the experimental group 2, over the control one at both 4 and 17 weeks of age: the experimental chickens had a larger mass and length of the intestine, as well as a larger mass of the spleen and cloacal pouch. Higher indicators of chickens of experimental groups were gained mainly due to the better functional state of the digestive system due to feeding in ovo. The introduction of carbohydrates stimulated the development of the gastrointestinal tract, affecting the production of mucin by goblet-like intestinal cells. As for the chickens of group 2, their advantages in development could be explained by the positive influence of probiotics. Lactobacilli probably contributed to the appearance of colonization resistance against the background of displacement and competition with conditionally pathogenic microflora. In addition, the intestinal microflora contributed to the formation of immunobiological reactions in the body, namely: stimulating the lymphoid apparatus, increasing the activity of lysozyme, provided the synthesis of immunoglobulins, interferon, and cytokines. Conclusions. Feeding in ovo using carbohydrates and probiotics as suppositories of prenatal nutrition of chicken embryos had a positive effect on the development and functional state of the digestive system, providing experimental chickens with additional development benefits during the initial growing period. According to research results, feeding in ovo has a positive effect on the postnatal development of chickens.