Synchronization of follicular wave emergence in the seasonally anestrous ewe: the effects of estradiol with or without medroxyprogesterone acetate.

Fertility is often lower in anestrous compared to cyclic ewes, after conventional estrus synchronization. We hypothesized that synchronization of ovarian follicular waves and ovulation could improve fertility at controlled breeding in anestrous ewes. Estradiol-17beta synchronizes follicular waves in cattle.

Effects of treatment with GnRH from 4 to 8 weeks of age on the attainment of sexual maturity in bull calves.

In bull calves an early transient increase in circulating concentrations of LH occurs between 6 and 20 weeks of age. This has been shown to influence reproductive development and performance later in life. In an attempt to hasten the onset of sexual maturity, bull calves (Hereford x Charolais) were treated (im) with 120 ng/kg of GnRH (n=6) twice every day from 4 to 8 weeks of age; control calves received saline (n=6).

Changes in serum luteinizing hormone (LH) concentrations in response to luteinizing hormone releasing hormone (LHRH) in bull calves that attained puberty early or late.

The objectives of this study were to determine if the response to luteinizing hormone releasing hormone (LHRH) could be used to select bull calves capable of early sexual maturation and to establish the optimum route and dose of LHRH. In Trial 1, at 4, 10 and 20 week of age, 20 calves were treated iv with 2 microg/kg body weight of LHRH 1 and 5h after commencing a 9-h period of blood sampling. Bulls were separated into early and late maturing (n=10), based on age at puberty (scrotal circumference (SC) of >or=28 cm).

Effects of treatment with LH or FSH from 4 to 8 weeks of age on the attainment of puberty in bull calves.

A transient increase in gonadotropin secretion between 6 and 20 weeks of age is critical for the onset of puberty in bull calves. To try and hasten the onset of puberty, bull calves were treated (s.c.

Craniomandibular osteopathy in a bullmastiff.

A 6-month-old bullmastiff was presented with bilateral painful swellings of the mandible. Craniomandibular osteopathy was diagnosed based on skull radiographs and histological findings from bone biopsies. Treatment consisted of meloxicam to alleviate the pain.