INFLUENCE OF BULL’S BODY TYPES AND MEAT FORMS EXPRESSION ON THEIR SEXUAL ACTIVITY

In beef cattle breeding, the reproductive capacity of bulls significantly affects the economic efficiency of production. Selection for the meat productivity can negatively affect the ability of bulls to reproduce, so it is necessary to consider the risks of such a connection when selecting them. The study determined the rate of manifestation of Ukrainian beef breed bulls sexual reflexes of different body types and severity of meat forms. According to the type of body structure of bulls divided into two groups: large (high and long-bodied) and compact (low and short-bodied). The distribution performed using the growth index. The severity of meat forms of bulls was determined at 15 months of age on a 60-point scale. The animals on meat forms divided into two groups compared with the average score of experimental bulls. The degree of sexual activity manifestation assessed by the duration of sexual reflexes from bringing the bools to the stuffed animal to the mating attempt. According to the manifestation of libido, animals divided into three groups: active – mating attempt to cage from 10 to 60 seconds, moderate – from 60 to 120 seconds and slow – the time before the mating attempt lasted more than 120 seconds. Subsequently, in experimental bulls recorded the duration of productive use period, the number of leads to the stuffed animal and mating attempts to it and the number of received and rejected ejaculates. It found that the tendency of the distribution of active moderate and slow manifestation of sexual reflexes in bulls of different body types and development of meat forms is similar. In bulls of different groups, moderate sexual activity most often observed, but specific tendencies observed within the groups. The share of high sexual activity was higher in compact bulls compared to large coeval animals. Among animals grouped by the development of meat forms, the share of high sexual activity higher in bulls with better expressed meat forms. In the future, large bulls tend to increase the duration of productive use, predominate in the share of mating attempt and are characterized by a decrease in the share of ejaculate culling. Bulls with better meat forms tend to increase the duration of productive use due to their higher breeding value in terms of meat productivity. No difference was found in the proportion of mating attempts and the percentage of culled ejaculates between animals with different manifestations of meat forms. The obtained results prove that for intensive use at a young age more suitable bulls of compact type, and in adulthood more effective large sires. Better development of meat forms somewhat reduces the sexual activity of young bulls. At a more mature age, the results of the use of bulls are practically unaffected by meat forms.

Increasing the reproductive function of boars by introducing phosphatide concentrate into their diet

As a result of a number of experiments and studies, it was found that the introduction of phosphatide concentrate in addition to the main diet of boars in the amount of 1.0; 2.0; 3.0% allows to increase the manifestation of sexual reflexes. Also, the inclusion of this concentrate increases both quantitative and qualitative indicators of the sperm of experimental boars, which in the experimental groups allows increasing the number of piglets at birth by 7.9; 18.9; 19.7%, respectively, while the cost of obtaining them is reduced by 7.3; 16.0; 16.5%, respectively, compared with the control group.

The sexual activity of the ram-sires, depending on their mode of use

Literary data are presented and their analysis is conducted regarding the mode of use of ram-sires and their effect on sexual activity and sperm productivity. The results of research of scientists with recommendations of optimal modes of use of fetuses for semen production and its cryopreservation in non-pairing and steaming periods are presented. According to the results of the analysis of many researchers, the activity of the sexual reflexes of the rams in the spring and summer decreases by 1.4 times compared to the winter. At the same time quantitative indicators of sperm productivity decrease. However, M.M. Aibazov (1987) experimentally confirmed that sheep-breeders of the Caucasian fine-breed and Australian merenos breed exhibit high sexual activity and produce sperm of satisfactory quality in all seasons. Similar results were obtained by British researchers in the study of sexual activity and sperm productivity of ram-sires of British breeds. A.A. Ivanov (1987) indicates the regime of use of ram sires, for five years with obtaining and subsequent freezing in the unpaired period 6 ejaculates (2 doublets 3 times) per week and in the breeding season 10 ejaculates (2 doublets 5 times) week. P.P. Kundyshev (2004) considers it possible and proposes to obtain from the breeding rams for cryopreservation and storage during the year, both unpaired and steaming periods, with daily ejaculate production. This mode, according to the author, provides a sufficiently high fertility sperm up to 50.3 percent. In the study of sexual activity and sperm productivity of ram-sires of different breeds, including the North Caucasian meat-wool, jalgin merino, Soviet merino, maniche merino, Russian meat merino, Edelbaev, polldore P.P. Mammoth and others. (2018) found that the most active were the rams of the Edinburgh breed, which took 22 seconds. ejaculate secretion, and the slowest texel breeders, which took 39 seconds to ejaculate. The rams of the other breeds listed above spent 25 to 34 seconds to ejaculate. In addition, rams of Texel breed produced the lowest activity sperm, and therefore only 19 sperm were frozen from one ejaculate, with an average of 20 to 26 sperm species tested.

Ejaculate quality is influenced by boar behaviour at the time of collection

Ejaculates were collected from the same boars twice a week, in spring during two years. Most animals had very good sexual reflexes and were scored as 5. They gave ejaculates which had good volume, concentration and motility and could be processed into the largest number of insemination doses. This had an obvious positive economic effect. Age influenced ejaculate quality in young boars, with the exception of a few animals in which sexual reflexes were diminished. Nevertheless, ejaculates had the necessary characteristics and could be processed.