Growth and development indicators of cross-breed young sheep in the conditions of the Republic of Tuva

The aim of the study is to investigate the growth and development of crossbreeds obtained by crossing Tuvan coarse-wool short-fat-tailed ewes and a Gorno-Altai breed stud ram. The studies were conducted in 2023 in a private subsidiary farm in the village of Bayan-Kol, Kyzyl District, Kuu-Dag locality. As a result of crossing, first-generation crossbreed offspring were obtained. The obtained Gorno-Altai-Tuvan crossbreed young animals (experimental group) and purebred young animals of the Tuvan coarse-wool short-fat-tailed breed (control group) were selected for the experiment. Live weight was studied; absolute, average daily and relative gains were calculated. Measurements were also taken from the animals under study and body condition indices were calculated. The studies showed that the live weight of the crossbred young animals at birth was 5.16 kg, and at six months of age it was 37.48 kg, which is 1.28 and 1.14 times higher than that of the Tuvan short-fat-tailed breed, respectively. The crossbred animals grew well in width and had a more developed skeleton: the width at the hips (18.18 cm), chest girth (93.13 cm) and metacarpus girth (8.88 cm) were 1.37, 1.04 and 1.1 times higher, respectively. The measurements confirm the calculated indices of constitution: the index of massiveness of the crossbred young animals was 165.2 %, the index of bone content was 15.75 %, which is higher than that of purebred animals by 1.08 times and 1.14 times, respectively. However, the relative increase was 1.05 times higher in purebred young animals and was 156.0 %, which is most likely a consequence of the higher adaptability of Tuvan short-fat-tailed sheep to natural and climatic, feed conditions and their resistance to unfavorable factors.