Pregnancy rate, calving interval, birth weight, weaning weight, and quarterly BCS were collected for 5 consecutive years on 454 fall-calving multiparous British crossbred cattle (3 to 10 yr of age) to evaluate associations of age with BCS and production parameters. Body weight and BCS were collected pre-calving, prebreeding, at weaning, and midway through the second trimester of pregnancy (Augu...

Background: Presynchronization could enhance fertility in timed breeding programs. The best presynchronization method has to justify biological requirements and to provide practical and economic advantages. OBJECTIVES: Present study investigated the effectiveness of presynchronization with equine chorionic gonadotropin (eCG) before ovsynch (eCG-ovsynch) compared to conventional presynch-ovsynch...

We investigated the effect of stage of pregnancy on estimates of breeding values for milk yield and milk persistency in Gyr and Holstein dairy cattle in Brazil. Test-day milk yield records were analyzed using random regression models with or without the effect of pregnancy. Models were compared using residual variances, heritabilities, rank correlations of estimated breeding values of bul...

Environmental effects on fertility measures early in lactation, such as the interval from calving to first luteal activity (CLA), proportion of samples with luteal activity during the first 60 days after calving (PLA) and interval to first ovulatory oestrus (OOE) were studied. In addition, traditional measurements of fertility, such as pregnancy to first insemination, number of inseminations pe...

Five experiments evaluated the effects of supplemental Ca salts of PUFA on reproductive function of Bos indicus beef cows. In Exp. 1, nonlactating and multiparous grazing cows (n = 51) were assigned to receive (as-fed basis) 0.1 kg of a protein-mineral mix + 0.1 kg of ground corn per cow/d, in addition to 0.1 kg per cow/d of 1) Ca salts of PUFA (PF), 2) Ca salts of SFA (SF), or 3) kaolin (contr...

d before initiating treatments. Cows were blocked by lactation number and assigned randomly to 3 treatments consisting of variations of the Ovsynch protocol. Cows in Cosynch-48 and Ovsynch received injections of GnRH 7 d before and 48 h after a PGF injection. Fixed-time inseminations (TAI) were made at the time of the second GnRH injection (0 h; Cosynch-48) or 24 h (Ovsynch). Those in Cosynch-7...

in recent years, sexed semen has been commercially available. due to its lower fertility and higher price compared to conventional semen, economic evaluation should be undertaken before recommending the technology to dairy producers in each country. the objectives of the present study were to evaluate the advantages and disadvantages of the sexed semen usage at farm level in economic conditions...

background: the pregnancy was a risk factor for excessive weight gain for women. however, there is no information about the prevalence of obesity and its relationship with a history of pregnancy in girls. therefore, the purpose of this study was to investigate differences in the prevalence of obesity in adolescent females with a history of pregnancy and fac­tors associated with it, in korea. me...