van der Host, GerhardMenkveld, RoelofSeier, Jurgen Victor2023-05-102024-11-042023-05-102024-11-041995https://hdl.handle.net/10566/17250>Magister Scientiae - MScIn biomedical research limited use has been made internationally of African non-human primates. As a result, their reproductive physiology has been less well defined, when compared to the more commonly used macaque species. There have also been no extensive developments in the associated field of assisted reproduction for African non-human primates. To contribute to the knowledge of the reproductive physiology of African non-human primates, this study presents semen characteristics from the vervet monkey. The focus is on abnormal sperm morphology which has not been described in detail. AII individuals utilized here either wild caught or colony bred and maintained in an indoor laboratory breeding colony. A detailed description of the frequency and prevalence of specific morphologically abnormal forms of sperm from vervet monkeys and illustrations of the different types of abnormalities is provided for the first time. Most features, such as the prevalence of tail abnormalities, particularly coiled and bent tails, were similar to what has been reported for other OId World cercopithecines. A total of 28 types of morphologically abnormal forms were found including 13 head abnormalities, seven midpiece abnormalities and eight principal- and endpiece abnormalities. Sperm head abnormalities were rare, occurring at a rate of less than 2t in each group. Except for the nipple defect, there was no difference between colony bred and wild caught individuals in the rate at which defective forms occurred. on the other hand not aII types of abnormalities were found in each group. A relationship between morphology and fertility could not be established because some individuals with the highest rate of abnormal morphology were successful breeders. Evaluation of consecutive ejaculates revealed highly variable semen characteristics both within and amongst different individuals. This observation extends to other sperm characteristics such as the concentration, vitality, speed of forward progression (F.P) and motility. The evaluation of reproductive potential based on one or two ejaculates is therefore not possible. The pH of vervet monkey semen was similar to that of humans. out of two indicator papers tested to determine this variable, only one was found to be reliable in terms of reference values obtained with a pH meter. Another aim of the study was to develop a cryopreservation method which yields a satisfactory post-thaw recover of progressively motile sperm. No specialized equipment other than a liquid nitrogen storage container was needed. Semen samples were diluted with a Tes-Tris extender containing 5% glycerol before being cooled to 50 over 3O minutes. This was followed by aspiration of the samples into paillettes and freezing to a plunge temperature of -139oC for 20 minutes in liquid nitrogen vapour. The paillettes were finally stored in liquid nitrogen. Conspicuous features of this method were the addition of glycerol at 32oc, a short glycerol equilibration time, a fast freezing rate, a low plunge temperature and a fast thawing rate.enReproductive physiologyMale vervet monkeysLaboratory environmentsAbnormal sperm morphologyCryopreservation methodsUniversity of the Western Cape