Thesis (MSc (Veterinary Sciences))--University of Pretoria, 2001. / Includes bibliographical references.

Thesis (Ph. D.)--Rutgers University, 2009. / "Graduate Program in Endocrinology and Animal Biosciences." Includes bibliographical references (p. 94-104).

Abstract This study evaluated the effect of repeated superovulation and embryo recovery in 15 Boer goat does. Does were synchronised for oestrus using CIDR’s for 17 days and superovulated with pFSH during the natural breeding season (autumn). Cervical inseminations with fresh undiluted semen were performed 36 h and 48 h following CIDR removal and the embryos surgically flushed six days after the second AI. Does superovulated for the first time recorded a shorter mean (± s.e.) induced duration of oestrus (20.8 ± 1.0 h), when compared to those repeatedly superovulated (30.4 ± 6.7 h). The mean (±s.e.) number of structures and embryos recovered were significantly lower in does treated repeatedly (6.0 ± 1.7 and 3.8 ± 1.7) than does superovulated for the first time (12.9 ± 0.5 and 11.7 ± 0.5), respectively. The mean (±s.e.) number of unfertilised ova per donor was significantly higher in repeatedly superovulated does (5.5 ± 1.6), compared to does superovulated for the first time (0.1 ± 0.1). The fertilisation rate and the number of transferable embryos were significantly lower in does treated repeatedly, compared to does superovulated for the first time. These results indicate that the number of times that a Boer goat doe can be utilised as the embryo donor may be limited to three times.

Derivative free restricted maximum likelihood (DFREML) was used to calculate variance and covariance components for cumulative milk yield, cumulative fat yield and cumulative protein yield, of Alpine, Toggenburg, Saanen and Nubian dairy goat breeds. First lactation records of 691 Alpine, 641 Toggenburg, 439 Saanen and 433 Nubian goats freshening between 1986 and 1995, and a combined data set of all breeds, were analysed. Two basic models, either including or excluding coefficients for phantom groups, besides the random and fixed effects, were fitted for each trait and breed. Included fixed effects were age at first kidding and flock-year for the single breed data sets and an additional breed effect for the multiple breed data set. Random effects in sub-models were fitted to estimate direct effects (model 1), direct and maternal effects (model 2) and direct effects, maternal effects and the covariance between direct and maternal genetic effects (model 3). (Abstract shortened by UMI.)

Transport, a common cause of stress in livestock, has been documented to increase cortisol, and epinephrine in goats. However, little is known about the timing of changes in the immune system in these stressed animals. The objective of this study was to determine whether expression of immune-related genes changes in goats that are exposed to transport stress. In this study, 15 Spanish-Boer goats ranging from 3 to 4 yrs of age were transported for 12 h. Goats were divided into 5 groups of 3 and placed in 1.219 m x 1.219 m pens. Blood samples were collected via jugular veni-puncture from each animal at 0 h, 3 h, 6 h, 9 h, and 12 h of transport, plasma and leukocytes were harvested for cortisol analysis and PCR analysis for gene expression. Data was analyzed using trailer location (group) as the experimental unit in a mixed model, repeated measures analysis of variance with compound symmetry and autoregressive covariance structures, depending on the best fit for each model. Percent weight losses were analyzed using a diagonal covariance mixed model. Hourly temperature humidity index (THI) values inside the trailer and from the shade were analyzed using a two-independent sample T-test. Cortisol concentrations were significantly elevated during transport (P<.049), indicating that goats experienced stressful events during hours of transport. Cortisol concentrations peaked after 6 hours, and returned to near basal concentrations after 12 h of transport. There was an overall trend for greater expression of many of the genes of interest to increase expression after 12 h of transport, but none were significantly different from pre-transport expression values. Overall, the data suggests that the goats transported during this study experienced transport stress, as indicated by the elevation in cortisol concentrations, but did not have significant changes in expression of the immune-related genes after 12 h of transport.

Thesis (MSc. (Veterinary Tropical Diseases)--University of Pretoria, 2008. / Includes bibliographical references. Also available in print format.

Thesis (PhD (Veterinary Science))--University of Pretoria, 2007. / Includes bibliographical references. Also available in print format.

Thesis (M.S.)--West Virginia University, 2008. / Title from document title page. Document formatted into pages; contains vii, 91 p. : ill. (some col.). Includes abstract. Includes bibliographical references.

Thesis (MMedVet. (Vet. Public Health))--University of Pretoria, 2003. / Includes bibliographical references.

Thesis (PhD. (Surgery, Companion Animal Clinical Studies))--University of Pretoria, 1999. / Also available in print format.