This study investigated the effect of GnRH analogues on inducing ovulation of dominant follicle (DF)and subsequent corpus luteum (CL) lifespan in the presence of norgestomet implant in Holstein heifers. Onday 6 to 8 of the estrous cycle (day 0 of the experiment), all heifers (n=15) received norgestomet implantfollowed by prostaglandin injection on days 0 and 1. On day 4, group 1 (n=4) and 2 (n=...

The present study was conducted on buffaloes that were non-cycling (heifers, n=32; lactating, n=13) or cycling (heifers, n=11; lactating, n=27) and in the buffaloes that conceived (heifers; n=11; lactating, n=23)or failed to conceive (heifers, n=32; lactating, n=17) subsequent to artificial insemination. Plasma samples were analyzed for thyroid stimulating hormone, thyroid hormones, glucose, to...

this study was performed to determine the effect of injecting selenium into pregnant heifers at the last stage of gestation on the serum se, cu, zn and fe status of the heifers and their calves. fifty holstein heifers were randomly assigned to one of five treatments. four and two weeks before the expected time of calving, the heifers were injected intramuscularly 10 ml (t1), 20 ml (t2), 30 ml (...

The objective of this study was to investigate the effect of equine chorionic gonadotropin (eCG) on ovarian follicles at three stages of development (emergence, dominance and early static phases) during the first follicular wave (FFW) in Holstein heifers. Heifers (n=20) were randomly assigned into four experimental groups (n=5 in each group). Heifers received eCG (500 IU; Folligon®; Intervet, H...

Decisive heifer management for improved lactation and reduced dystocia requires a systematic analysis of age, body weight (BW), and average daily gain (ADG) using an adequately large sample size. The objective of this study was to determine effects of BW and age at first breeding and ADG until pregnancy on yields of milk, milk fat, and milk protein in the first lactation and the occurrence of d...

Studies were conducted to determine the relationship between allometric measures of growth of Holstein dairy heifers and placing in the show ring, and to compare differences in growth between Holstein heifers that are shown and not shown. In the first study, 494 Holstein show heifers were evaluated at the 2012 and 2013 Georgia Junior National Livestock Shows. Measurements were obtained for weig...

Postweaning heifer development systems were evaluated at 2 locations in a 4-yr study for their effect on performance and subsequent adaptation to grazing corn residue as a pregnant heifer. In Exp. 1, heifers were blocked by BW and randomly assigned to graze winter range (WR) or graze winter range and corn residue (CR). In Exp. 2, heifers were assigned to graze winter range and corn residue (CR)...

The phosphorus requirements for dairy heifers (0.20-0.35%) and endogenous concentrations (0.20-35%) of P in feeds fed to dairy heifers are similar, suggesting that the need for supplemental P in dairy heifer diets may be minimal. Because long-term P feeding studies on dairy heifers are unavailable, 183 Holstein heifers and 182 backcross Holstein × Jersey heifers were offered diets with (SP=0.40...

Ninety crossbred beef heifers averaging 260 kg were blocked by weight and allotted randomly to 15 pens of six heifers each, with three replicates per treatment. The treatments were spayed heifers (S); intact heifers (I); S + Synovex-H7 (SH); I + Synovex-H (IH); and S + Synovex-S7 (SS). The heifers were spayed vaginally with a Willis instrument; intact heifers were rectally palpated for reproduc...

Twenty-four Angus x Holstein heifers were utilized in the single-calf heifer system. Calves were weaned from one-half of the dams between d 64 and 89 postpartum. Dam’s were gradually adapted to a high concentrate diet over a four wk period at the beginning of the trial. Heifers that had their calves early weaned (EW) gained 44.2% faster (P < .01) and consumed 10.8% less (P < .05) DM than lactat...