INTRODUCTION I t is economical ly important to Thoroughbred breeders that barren and maiden mares exhibit normal, ovulatory oestrous cycles and also conceive as early as possible during the breeding season. In winter, most but not all non-pregnant mares pass through a period of anoestrus, or sexual and ovarian inactivity (anovulatory period), when neither developing follicles nor corpora lutea ...

The incidence of oestrus (6/46) and ovulation (14/46) in ewes given antisera to androstenedione, oestrone, oestradiol and testosterone either separately or as a mixture of these sera at the time of treatment with progestagen sponges alone or progestagen sponges followed by LH-RH was similar to that of control ewes (2/13 and 6/13 respectively). The number of corpora lutea (CL) recorded for those...

Plasma progesterone concentrations measured by radioimmunoassay in the Natal clinging bat remained below 2.01 ng/ml during lactational anoestrus but increased significantly during the period of delayed implantation. Values peaked at implantation but were followed by a significant decrease thereafter. Concentrations remained low (less than 6.0 ng/ml) during the initial period of fetal developmen...

What constitutes audience engagement? What elements of a show produce the most social activity? Much attention has been paid to Twitter’s ability to capture real-time audience reactions and sentiment towards a television show, but little is known about what subjects drive an individual to tweet (or conversely, not to tweet). Though common sense may suggest that especially provocative, humorous,...

A seasonal infertility in pig breeding herds is observed in Australia and overseas. It is characterised before mating by an increase in the incidence of anoestrus, delayed puberty in gilts and prolonged wean-to-mate intervals, and after mating by reduced conception rates, delayed returns to service, an increase in sows not-in-pig when due to farrow and possibly by increased abortions. Litter si...