Ucar O. , M. Kaya, S. Yildiz , F. Onder , M. Cenesiz , M. Uzun: Effect of Progestagen/PMSG Treatment for Oestrus Synchronization of Tuj Ewes to be Bred after the Natural Breeding Season. Acta Vet. Brno 74, 2005: 385-393. The aim of this study was to investigate the effect of pregnant mare serum gonadotrophin (PMSG) and progestagen sponge on oestrus synchronization of Tuj ewes mated after breedi...

The objective of this study was to investigate the effect of hCG administration 5 days after breeding on plasma progesterone (P4) concentration and reproductive performance of oestrous-induced nulliparous dairy goats. A total of 59 nulliparous goats (36 Alpine and 23 Saanen) received intravaginal sponges with 60 mg medroxyprogesterone acetate for 9 days plus 200 IU equine chorionic gonadotrophi...

The chemical profiles of vaginal fluid collected from cows in oestrus and nonoestrus were analysed by gas chromatography-mass spectrometry (GC-MS) to establish any qualitative differences that might have potential value in bovine biocommunication. Eight different organic compounds were detected using the two chromatograms. The chemical profiles of oestrus vaginal fluid were distinguished signif...

Treatment of female mice with bromocriptine on Day 1 or 3 of pregnancy induced many of the females to return to oestrus. The incidence of extended cycles (7--10 days) and pseudopregnancies following this return to oestrus was significantly higher than in unmated control females. These observations are consistent with the existence of a 'mnemonic' component of the luteotrophic system in the mouse.

Control of oestrus in dog and cat can be divided into 2 parts, contraception and induction of oestrus and ovulation. For contraception, either dog or cat is operated by hormonal applications in the same way. Progestins have been used for a long time to postpone estrus with their major side effects. Nowadays, other hormonal remedies become more accepted such as a long term implants of GnRH agoni...

Lactation delays the re-initiation of oestrous cyclicity in rats, resulting in physiological sterility for the duration of suckling. During this phase, the secretion of pituitary gonadotrophins is suppressed by an unknown mechanism. Continued application of the suckling stimulus by litter replacement (Bruce, 1958; Nicoll & Meites, 1959), or injections of prolactin (Meites & Nicoll, 1959), have ...

Ewes in which oestrus had been synchronised were artificially inseminated (at the second synchronised oestrus) 17 to 21 days after placement on plots containing either oestrogenic (Trifolium subterraneum L. c% Dinninup) or non oestrogenic pasture. A comparison of the reproductive performance indicated that grazing oestrogenic pasture prior to and during joining reduced the proportion of ewes in...

To compare an injectable progesterone (MAD-4) with an intravaginal device (IPD), and natural O17 with synthetic oestradiol (OB) in a synchronisation protocol, 51 cows were divided into four groups. Each group was treated with one of the two sources of progesterone and one of the two oestradiol formulations. Oestrus behaviour, follicle diameter, and pregnancy rates were evaluated. Oestrus behavi...

This paper reviews the influence of social mechanisms on oestrus and sexual motivation in pigs. The social relations between the animals and the signals they send out can inhibit as well as encourage their social motivation. Social stimuli from both boars and other sows in oestrus tend to induce and synchronise oestrus and ovulation amongst sows. The courting behaviour of boars is also facilita...