Age dynamics of the stomach and intestines’ anatomical parameters of the budgerigar (Melopsittacus undulatus)

The object of research was the morphofunctional organization of the stomach and intestinal of the budgerigar (Melopsittacus undulatus) in the postnatal period of ontogenesis. The aim of the work was to determine the age topography and anatomical structure characteristics of the stomach and intestines from the budgerigar (Melopsittacus undulatus). The material for morphological studies was selected from budgerigars of 9 groups: 1-, 3-, 7-, 14-, 21-day-old, 1-, 2-, 6-month-old and 1-year-old (n = 5). The absolute bodyweight of parrots and their organs was determined using a ВЛКТ-500 balance and a «Techniprot Waga Torsyjna-WT 500» torsion balance. Linear indicators of organs were determined using a ruler (GOST 17485-72) and a calliper (GOST 166-89). According to the research results, it was found that the increase in body weight of parrots during the first year of life was uneven. In the first month, it was increased by 15.3 times, in the second month – by 1.1 times. During the first month, it was increased most intensively in the first week. Parrots reached the mass of an adult bird at the age of 2 months. During the first year of life, the greatest body weight was established at the age of 6 months, and the greatest absolute weight, linear indicators of the glandular and muscular parts of the stomach, as well as the intestines – at the age of 21 days. The glandular stomach of the budgerigar reached the highest relative weight indicators at the age of 3 days, and the muscular part of the stomach and intestines – at the age of 7 days. The length of the intestine increased most intensively in the first week of life. During the first year of life, the relative length of the budgerigars small intestine gradually decreased. The greatest indicators of the duodenal absolute length were established at the age of 60 days, lean – 60 days, ileum – 21 days. The greatest indicators of the duodenal relative length were established at the age of 30 days, jejunum – 7 days, ileum – 14 and 21 days. High linear indices, as well as indices of the stomach and intestines mass of budgerigars, indicated their key importance in providing the body with nutrients and biologically active substances during intensive growth.