The effect of theileriosis on the reproductive function on Boran/Friesian cross heifers

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Rufus M R
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Rufus M R
This thesis describes studies that were undertaken to evaluate the effect of T. parva infection on the reproductive function of BoranlFriesian cross heifers. The study was conducted in four separate experiments. In Experiments 1 and 2, the animals were monitored for cyclical status post-infection. In Experiments 3 and 4, the infected animals were divided into two groups: one group was monitored for cyclical status and the other for both cyclical and pregnancy status after exposure to a bull. The reproductive function was assessed by routine monitoring of oestrus behaviour, palpation of the genital reproductive tract per rectum and determination of serum progesterone (P4) concentrations. Further, in view of observed acyclicity in the early work, attempts were made to assess the pituitary response to gonadotrophin releasing hormone (GnRH) in a group of animals (Ch. 5) in an attempt to explain partly the mechanisms involved in the impairment. Animals were monitored for the progression of disease by clinical and parasitological responses. Further, subject to death or sacrifice, a macroscopic and histological examination of target and various other organs and tissues was undertaken in an effort to establish the part played by observable pathological changes in the development of impaired reproductive function.