Analysis of interbreeding and age-dependent indexes of reproductive ability of cows.
Authors: Bondarenko Irina , Velikodna Kristinа 
Published: June 2021

Comparative estimation of the periods sexual cycle under futile inseminations cortex and heifers sexual mature age in facilities Sumy region.
The profitability of dairy farming in the farms of Sumy region will remain an unresolved issue to this day, as the indicators of reproductive capacity of breeding cows and repair heifers need analysis and correction. Inadequate feeding and inadequate care of pregnant cows and parturients are often added to this. As a consequence of the above - the reproductive capacity inherent in this species of animals is not fully realized, most cows remain infertile, and farms are short of calves and milk. The percentage of barren animals can be calculated only at the end of the calendar year, taking into account the data of statistical reporting, while infertility must be fought daily. Detection of infertile animals is effective only in the case of regular obstetric and gynecological medical examinations on the farm. It is during this time that experts find out the causes and calculate the percentage of the main components of infertility, which includes anaphrodisia. The article presents the results of the study of the main folds of anaphrodisia of cows and repair heifers of the experimental farm of Sumy region. The results of obstetric and gynecological examination, indicators of reproductive capacity of cows and heifers of mating age, reflect the basis of technology used in the economy, the intensity of use of breeding stock, as well as determine the economic feasibility of livestock in general. The main indicators of reproductive capacity of cows in the conditions of livestock farms are: indicators of inseminations, fertility, number of hotels, indicators of fruitless inseminations, and also duration of the service period The aim of the research was to study and analyze the components of anaphrodisia of cows and repair heifers of the farm during the experimental years. The results obtained will be a criterion for assessing the state of reproductive function of the uterine population of cattle. The research was conducted at Kosivshchynska Agricultural Company, Sumy District, Sumy Region, on Holstein-Friesian cows during 2019-2020. The main indicators of reproduction of uterine cattle were studied on the basis of annual reports. The obtained digital material was processed by methods of variation statistics using Student's parametric t-test. It was found that a significant percentage of culled animals occurred due to functional disorders of reproductive ability, namely due to repeated and ineffective inseminations. It was found that in 2019, 19.3% showed a sexual cycle after calving in less than 30 days, in 2020 - 18.9%, in 31-60 days in 2019 - 27%, in 2020 - 26%, in 61 -90 days in 2020 - 52.7%, in 2019 - 51.8%, for 91-120 days in 2019 - 22.1%, in 2020 - 23.5%. There is a steady growth of the service period, which worsens the performance of the experimental economy. It was found that the largest percentage of culled cows and repair heifers were animals with anaphrodisia: in 2019 33.7% of the total number of culled animals, in 2020 - 51.10%. The number of inseminations during the experimental years decreased, and the insemination index increased : in 2019 it was equal to 60, and in 2020 -80. Studies in this area highlight the problem of infertility in cattle, which encourages the study of this issue, and the search for ways to solve this problem.