TY - JOUR AU - S. V. Kuzebny, AU - G. S. Sharapa AU - S. Y. Demchuk PY - 2018/05/15 Y2 - 2024/03/29 TI - Methodological aspects of assessment of reproduction ability of cows JF - Animal Breeding and Genetics JA - Anim. Breed. and Genet. VL - 55 IS - 0 SE - Reproduction DO - 10.31073/abg.55.28 UR - https://abg-journal.com/index.php/journal/article/view/185 AB - Problems in cattle breeding in Ukraine and around the world are the reproduction and implementation of reproductive potential of cows. It is not possible to objectively compare the situation with the reproduction of bovine animals that has developed in different countries. In most cases, this is due to the different genetic characteristics of the livestock, the conditions for feeding and maintenance, even in a small territory, the peculiarities of national approaches in the organization of insemination and veterinary provision of animals, the application of various criteria for assessing the reproductive capacity of cattle, etc. Only in Ukraine for the characterization of reproduction ability is used a number of indicators such as calves output per 100 cows, the duration of restorative, service and interotional periods, the index of insemination, insemination of animals, reproduction capacity index (index), etc. Not isolated cases when the indicators used to evaluate are those that, until the physiological process of breeding, have only indirect effects, in particular the duration of the dry period, the keeping of calves, and others. One of the major drawbacks of most methods for assessing the reproductive capacity of animals is that each index reflects information about the specific aspect of reproduction, and has its own special meaning and its limitations. Therefore, in order to assess the state of play for a certain date or during a period, it is necessary to use a number of indicators at a time. Some indicators are used to assess the herd or population of cows, while others - to characterize the reproductive capacity of individual animals.The article presents the definition of indices and indices that reflect both group and individual assessment of animals for reproduction ability, and the advantages and disadvantages of each of the applied indicators: fertility from the first insemination, the index of ossification, the recovery period, service period, inter-hospital period, calves output for 100 cows, hunting index (level), index of carniveness, reproductive capacity, fertility index of cows (for Doha), index of fertility of cows (Wilcox). In addition to the main indicators in the article the definition and characteristics of certain additional factors that can change the level of reproduction in animals – the detection of sexual hunting, while distinguishing its intensity and accuracy. Intensity of detection of a larvae is the ratio of detected cows to their total number, and accuracy is the ratio of the number of animals in the nigger to the number of detected and the duration of the sexual cycle, which allows to control the determination of animals in hunting and to identify part of the cows with violations of physiological regulation. There are five ranges of duration of the sexual cycle: 2–17 days, 18–24 days (normal sexual cycle), 25–35 days, 36–48 days (two sexual cycles) and more than 48 days. In farms with a hunting detection system, the percentage of animals with a sexual cycle duration of 18–24 days should exceed 45%. If the number of animals with a cycle duration of 36-48 days increases and decreases with a cycle of 18–24 days, this indicates an inadequate detection of sexual hunting. An increase in the percentage of animals with 2–17 daily cycles indicates an increase in the number of animals with follicular cysts, and from 25–35 days and more than 48 days is an indicator of the early death of the embryo.According to the authors, the most objective indicators of the group evaluation are the duration of the service or interotional period, while for the characteristics of individual animals – the duration of the recovery period, the duration of the service period and the index of insemination. Taking into account the influence of a large number of factors on the reproductive capacity of cows, for their objective characteristics, it is necessary to use a set of indicators in order to be able to comprehensively assess the state of reproduction in the household and determine the main causes of reproductive losses. ER -