REGULARITIES OF MEAT-TYPE RABBITS’ GROWTH AND MEAT FORMATION PRODUCTIVITY DURING COMBINED TYPE OF FEEDING
The results of our own experimental studies of the patterns and characteristics of animal growth, the formation of meat productivity and its quality in the postnatal period (at the age of 1–30–45–60–90–120–150 days) in meat-type rabbits with a combined type of feeding were represented in the article. It was revealed that the highest growth energy of animals is observed in the period of 90 days. So, the absolute increase in this period is 1119.7 grams. The mass increase of the newborn in relation to an adult animal at 4-5 months of age is respectively 45-55 times. It was determined that both the body length and the chest girth behind the shoulder blades throughout the study period were increasing proportionally. So, the body length at 4-5 months of age corresponded to 52.0 and 54.1 cm, in comparison with the monthly age, this indicator increased by 1.8 and 1.9 times. The greatest mass in all age periods is characterized by the liver, lungs and kidneys. Throughout the study period, the specific gravity of the liver relative to body weight was from 3.4 to 4.4 %. Slightly less specific weight in the formation of liver was accounted for by the kidneys 0.4-0.6 % and lungs 0.4- 0.7 %.
It was found that the highest rate of increase in all parts of the body was characterized by a period from 120 to 150 days of age. The highest growth rates for the entire period were characterized by the mass of ears, skins and hind legs. From birth to 150 days, their mass increased by 48.0, 44.2 and 42.5 times. It should be noted that muscle tissue plays the main role in the weight formation of meat productivity, its largest increase in 3 months and is 75.3 percent relative to the mass of carcasses with fat without a head and liver, g. In addition, the slaughter yield indicator was determined. It was estimated that the rate of slaughter yield rises as well as age of rabbits increases, it was the highest at 5 months and was 49 percent, respectively. The quality of meat products was determined by studying the samples of experimental rabbits meat by chemical and technological indicators. The laboratory studies results of rabbit meat samples during different periods indicate the increase of the protein and fat amount with age increasing. The highest protein value was found in 150 daily rabbits of 20.6%, fat 6.4%, respectively. The corresponding ratio between parts of meat was determined by the unequal amount of protein and fat in different age periods of the rabbits. The greatest amount of protein per unit of fat was during rabbits slaughter in 90 days and is respectively 3.6: 1. The water-holding ability was determined by the technological indicators characterizing the carcass and meat. This indicator increased when the age of rabbits’ slaughter were also rising and months it was equal to 61.2% at 5 months. The measurements of skins at different age periods were determined. The skin area at the age of 90 days was 1647.4 cm² and belonged to the large skins group and increased to 1.0 and 1.1 times to 120 and 150 days old, which corresponded to 1720.6 and 1814.0 cm². The yield of products in rabbit breeding depends on the length, width and area of the skin. With the increasing of body length and chest girth behind the shoulder blades, the length and width of the skin also increased which were determined by the results of the studies