Morphological characteristics of the digestive tube organs in broiler chickens after feeding coarsely ground mussel shells

The relevance of the study is conditioned by the practical and scientific interest in feeding mineral feed additives from marine aquatic organisms and the effect of their particle size on the performance and condition of the digestive system in broiler chickens. In this regard, the purpose of the present study was to determine the effects of a feed additive made from sea mussel shells by coarse grinding on the growth rate and structure of the digestive organs of broiler chickens. To clarify this issue, histological studies of the tube-like digestive organs of chickens of the control and experimental groups were conducted, and their morphometric parameters were determined. Broiler chickens of the experimental group were fed with coarsely ground sea mussel shells in addition to the standard diet by free feeding. According to the findings of the study, the body weight of chickens in the experimental group stayed unchanged. In chickens of the experimental group, a decrease in the weight of the muscular part of the stomach and intestines and an increase in the length of the small intestine were found. An increase in the thickness of the epithelium and the area of the secretory portions of glands was observed in the crop and oesophagus, and an increase in the thickness of the cuticle and the mucosal lamina propria in the muscular part of the stomach. In the mucous membrane of the oesophagus and proventriculus, a larger number and area of lymphoid tissue accumulations in the form of small diffuse fields and lymph nodules were detected. In the duodenum of broiler chickens, the height of villi and the depth of crypts were lower, and in the caecum, the depth of crypts was lower. The morphological features of the crop, oesophagus, stomach, and small intestine, established upon the use of a mineral feed additive from mussel shells indicated the development of protective and adaptive reactions of the oesophagus and stomach to the traumatic effect of coarse particles of mussel shells, and the small intestine – to the increased calcium content in the chyme. The experimentally substantiated feeding of mineral feed additives from mussel shells to broiler chickens proved the need for their thorough grinding and dosed use in poultry feeding