THE LIVE WEIGHT AND BODY MEASUREMENTS OF THE RABBIT CROSS «HYLA» IN VARIOUS PERIODS

Introduction. At the present stage of livestock development in Ukraine, rabbit breeding as a sub-sector of livestock that meets the needs of society in dietary meat, fur and furs develops rather unstable, which is associated with numerous problems, the unsatisfactory level of breeding. Rabbit breeding features such as live weight, growth rate, meat yield, etc. are required to be improved. This will increase the production of valuable meat products rabbit meat. The main indicator of meat productivity of rabbits is their live weight. It is this sign of breeding that is the main factor in obtaining more meat.  The increase in live weight is associated with the biological ability of rabbits to intensive growth, which is characterized by daily increments. It is proved that in rabbits of specialized breeds of meat – New Zealand and California – the highest average daily gain is observed in the age from 20 to 135 days and makes up 35 g, while in rabbits of meat-and-fur breeds in the period from 45 to 150 days is 30 g. The studies confirm the existence of a connection between body measurements and live weight of rabbits, in particular between the chest and livestock weight between 0.45 and 0.56 and between the width of the lumbar and the live weight of 0.44–0.55, as well as a reliable positive the correlation between the width of the lower back and the slaughtered level at the level of 0,35–0,83, which makes it possible to increase the meat productivity due to the selection of rabbits with a wider width. According to the recommendations for working with the "HYLA" cross, the rabbit of the final hybrid in certain age periods should have the following values of live weight: when weaning at 35 days – 950–1050 g; at the age of 42 days – 1150–1400 g; at the age of 56 days – 1800–2300 g; at the age of 70 days (when slaughtered) – 2350–2650 g. The average daily gains of rabbit from weaning to slaughter, according to recommendations, should be from 43.5 to 47.5 g. The relevance of the work is in the studying of weight and linear growth of rabbits will reveal the most valuable genotypes of rabbits that are capable for intensive growth and production of enough valuable rabbit meat and allow to efficiently control the process of rabbit production. Purpose. The purpose of the research is to study the intensity of the weight and linear growth of the rabbits of the final hybrid of the "HYLA" cross, depending on the live weight of their father. Materials and methods of research. Studies of the weight and linear growth dynamics of the rabbits of the final hybrid of the "HYLA" cross were conducted in the conditions of LLC "Krolikoff" of Cherkasy oblast. For the experiment, there were formed 5 groups of rabbits, which were obtained from various male-female parents of the parental form of HYLA MAX and females of the HYLA NG cross type "HYLA". Dynamics of weight and linear growth of rabbits was studied after they were weaned from the mother. The following indices were determined: live weight, straight length of the body, chest circumference, shoulder width, lumbar width. To determine the type of body structure of animals, the mortality index was calculated, which is equal to the percentage of the chest circumference of the shoulders to the straight length of the trunk. Volume of ejaculate of males was determined according to zootechnical records. The live weight, the body size of the rabbits and the index of infirmity were determined in the corresponding age periods – 35, 56 and 70 days. The dynamics of animal growth was determined by absolute and average daily increments of live weight and body measurements.  Biometric processing of the obtained results was carried out using the PC in the MS Excel spreadsheet using the accepted techniques. Main results of research. At the age of 70 days, the highest value of live weight was found in the V-grope rabbits, which outweighed the young rabbits of the II group in 163.95 g (p < 0.001). Rabbits of I, III and IV groups have 0.45, 6.55, and 30.94 less live weight, compared to the young group V. In the chest circumference of the rabbit's shoulders of group I, the youngest of the group V was 0.81 cm dominant (p < 0.01). The width of the waist in the rabbits of this age was in the range from 5.14 (group IV) to 5.24 (V group). Obvious difference between these groups on this basis was not detected. In the period from weaning rabbits to slaughter, the young rabbits of V group were characterized by the highest absolute increments of live weight and width of the waist – 1590.01 g and 1.70 cm respectively.  However, with an absolute increase in the direct length of the trunk, the rabbit of the group I were ahead from those in group II by 0.94 cm (p < 0.001), while the young II group was 1.71 cm higher than the IV group (p < 0.001). It should be noted that for these characteristics, low and average coefficients of variation are observed during this period. By studying the average daily increments in live weight and rabbit weights from weaning to slaughter, it was found that the rabbits of the V group were characterized by the largest increase in live weight gain and dominated by analogues from the second group to 2.86 g (p < 0.001).  During this period, the direct length of the trout body of the I group was increased most intensively – the average daily gain of the sample was 0.34 cm, which is 0.03 cm more than the young of the second group (p < 0.01). For the period from 35 to 70 days of age, the coefficients of variation of average daily increments in live weight and body weight of the rabbits were low and average, indicating the consolidation of the studied characteristics in the crossbars of the final hybrid of the "HYLA" cross. Conclusion. The results of the conducted studies provide the opportunity to state that the rabbits, which are characterized by high growth intensity from weaning to slaughter, were obtained from the most-live-weight mass (26301 – 7.12 kg) (AP = 1590.01 g, SDP = 45,43 g), whereas the offspring of a male with a close to average live weight (No. 26351 – 6.90 kg) has the lowest rates of growth (AP = 1489.88 g, SDP = 42.57 g).  In general, the weight and linear growth of the rabbits of the final hybrid is at a high level and complies with the recommendations for working with the "HYLA" cross.