Animal science departments of the future.

Departments of animal science were established in agricultural colleges of public universities just over 100 yr ago, shortly before the founding of today's American Society of Animal Science. These departments and colleges have been remarkably resilient, changing little structurally. Yet, the future portends significant changes in these departments and colleges in response to shifts in how public higher education is financed and how society views the roles of animals in providing food and companionship.

Role of gonadotropin-releasing hormone pulse frequency in differential regulation of gonadotropins in the gilt.

We tested the hypothesis that different GnRH pulse frequencies will affect serum LH and FSH differently. Ovariectomized gilts (n = 6), immunized against GnRH, were given 200-ng pulses of GnRH agonist (GnRH-A) every 180 min for 3 days (pretreatment), followed by GnRH-A pulses every 30, 60, or 180 min for 3 days (treatment) in a Latin rectangle design. Mean gonadotropin concentrations did not change over time when GnRH pulses were administered every 180 min.

Evidence for a local role of inhibin or inhibin alpha subunits in compensatory ovarian hypertrophy.

The aim of this study was to determine whether immunoneutralization of inhibin altered compensatory ovarian hypertrophy. Crossbred postpubertal gilts actively immunized with a synthetic bovine inhibin peptide fragment (bINH) conjugated to human alpha globulins (HAG, n = 4 gilts) or HAG alone (control; n = 5) were unilaterally ovariectomized at mid-cycle. After unilateral ovariectomy, the remaining ovary was removed between day 8 and day 12 of the subsequent oestrous cycle.

Concentrations of hormones and metabolites, estimates of metabolism, performance, and reproductive performance of sows actively immunized against growth hormone-releasing factor.

Cyclic females actively immunized against growth hormone-releasing factor (GRF; n = 5) or human serum albumin (HSAi; n = 4) were used to determine the effects of reduced serum somatotropin (ST) and IGF-I on metabolism and production in gestating and lactating sows. Sows farrowed, pigs were weaned at 28 d of lactation, and sows were observed for estrus after weaning. Blood samples were collected at 15-min intervals for 5 to 6 h on d 110 of gestation and d 21 of lactation.

Ovulatory and endocrine responses after active immunization of gilts against a synthetic fragment of bovine inhibin.

The objective of this study was to determine whether neutralizing endogenous inhibin would affect ovulation rate and serum concentrations of FSH, LH, estradiol-17 beta, and progesterone in gilts. At wk 0, during their second postpubertal estrous cycle, gilts (195 +/- 2.4 d of age) were given a primary immunization against the 1-26 gly-tyr NH-terminal amino acid sequence of bovine inhibin-alpha conjugated to human alpha globulin (INH; n = 10) or against human alpha globulin alone (control; n = 10).