EFFICIENCY OF DIFFERENT METHODS OF DETERMINATION AND STIMULATION ESTROUS CYCLE OF CATTLE
Authors: Kuzebnyі S. V. 
Published: December 2018

In the conditions of industrial milk production and productivity growth in cows, the increase in the duration of the inter- calving period is noted. This is due to a somewhat prolonged process of involution of the uterus after calving in high-yielding animals and prolongation of the service-period due to lack of detection of animals in estrous cycle. Depending on the technology of maintenance and qualification of service personnel, the number of such animals may increase. The contributing factors include the year-round stall system of keeping cows, the uncontrolled retention of animals in large groups, short intervals of detection of animals in hunting and others. The paper uses the materials of the first-time animal and veterinary record of a number of husbandries specializing in industrial milk production with different systems of keeping animals and the detection of animals in hunting. Methods of hormonal stimulation of sexual intercourse in cows were studied in the state enterprise "Khrystynivske" (n = 243) for the binding system for the maintenance of cows and auto-mated control of motor activity of cows for unbroken maintenance for the detection of animals in hunting – LLC "Nd. a. Lesia Ukrainka" (n = 74). For hormonal stimulation, methods using estrogens and prostaglandins were used: the protocol Ovsinh (n = 164) and the use of progesterone (preparation Delta® Ceva Santa Animale) (n = 79). The obtained results were sorted by the methods of variation statistics in the software product Statistica 12.5. An analysis of the detection of spontaneous hunting in animals by the traditional method - observing them during the walk allowed us to establish that in the first cows, the indicators of regenerative (VP) and service-periods (SP), under the same conditions of abstinence and feeding, differed from full-age cows in the duration of only one sexual cycle (20–21 days), for almost identical index of insemination (IO). Analysis of the results of determining the sexual cycles of cows using the help of DATA SLOW software and Triolact sensors conducted at the LLC nd. a. Lesia Ukrainka of Kovel region of Volyn oblast (n = 74) showed that even short-term hunting, which takes place within 2–3 hours, can detect and carry out insemination of animals. The obtained results coincide with the duration of the service-period during the systematic visual detection of animals in the stage of sexual hunting, but there is a reduction of the three-fold of the recovery period, the duration of which is associated with certain difficulties of visual detection in animals of the first hunting (irreducible manifestation , short duration and others). Also, the results of the analysis confirm the increase in the service-period in cows-primates for approximately the duration of one sexual cycle. In the following cases, there is a decrease in the variability of reproduction rates. The growth of milk productivity negatively correlated with the indicator of the duration of service-period in cows. The force of influence was almost 96% (P < 0.01). In cases of tied animals maintenance in the first place, methods of hormonal stimulation of sexual hunting in cows are obtained. Indicator of efficiency of detection of animals in hunting during the period of maintenance was 28–35%, and during the summer-camp – grew to 47–62%. Analysis of the duration of the service period and the index of insemination with the synchronization of cows according to the protocol "Ovsinh" has shown a decrease in the effectiveness of insemination of cows for stimulated hunting. Fertility of animals after the first insemination was 20.1%, and after the second procedure the introduction of hormonal drugs increased by 8–12% and was 38%. In the application of progesterone in the form of vaginal applicators "Pride Delta" results were better – the fertility rate from the first insemination was 37%, and from two – 56%. As with the use of prostaglandin, and in the application of the protocol "Ovsinh" there is a tendency to increase the effectiveness of insemination, depending on the duration of the recovery period, that is, the time from calving to the use of the drug.