Exponentially weighted moving average control charts and neural networks were used for oestrus detection in dairy cows. The analysis involved 373 cows, each with one verified oestrus event. Model inputs were the traits activity, measured by pedometer, and the period (days) since last oestrus. In total 10,386 records were available, which were partitioned into training and validation subsets to ...

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 ...

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...

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...