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The objective of the work was to establish the effect of an ovaries hand massage on the reproductive activity and hormonal changes during winter anestrus and luteal phase of estrous in mares. The examinations were done on 10 mares (Polish pony) in January 1992 during winter anestrus and in August 1993 during luteal phase of estrous cycle (diestrus), divided into 2 groups: experimental and control. In the experimental group ovaries were massaged ever day for 30 sec. Sexual behavior of mares was checked every day with the help of a stalion, ovaries were examined per rectum and by USG. The level of progesterone and estradiol was determined every second day in venous blood (from the external jugular vein). It was found that ovarial massage did not significantly affect reproductive activity and hormonal activity of ovaries during winter anestrus. A possibility of shortening of estrus during reproductive season during the luteal phase of estrous (diestrus) was found.
Semen quality undergoes seasonal changes induced by multiple environmental factors of which the lenght of day­light plays the most important role. The pineal gland and its secretions are mediators in the transmission of light information. Sexual activity in rams increases during the shortening of daylight length. Therefore an application of artificial light programme enables to obtain a few breeding seasons within a year. Many experiments have shown that maintenance of proper light rigour may extend the period of a high sexual activity typical for a breeding season. Currently performed studies try to explain what systems are responsible for photosensitivity in these animals and in what way theoretical studies may be used in practice of the species reproduction.
Fecundity and reproductive activity of 179 females of Argas (A.) reflexus in laboratory conditions, i.e. at temperature 23 ± 1°C and 75% of relative humidity were observed. Under these conditions reproduction activity of females fed in spring lasted since March till August. However, most of females (63.0-91.8%) laid eggs in June and July. Disturbances in egg-laying process of Argas (A.) reflexus females fed in abnormal time, i.e., in autumn and kept in laboratory conditions, were stated. These females were active since December till July (maximum activity was observed in February-34.3% and March-40.0%). Preoviposition and oviposition periods were observed in this study, too.
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