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There are a number of monkey species in Kenya, but of particular interest are olive baboon (Papio cynocephalus anubis), Vervet monkeys (Chlorocebus aethiops, commonly known as African green monkeys) and Sykes (Cercopithecus mitis). Among the three species, baboon and vervet monkey seem to be more promising as models for human heath studies including reproductive research. Vervet monkey as a model has a number of advantages including being more readily available, successful in breeding in captivity, a relatively short time to reach maturity (3-4 years) and its small size allows easy handling and low maintenance cost. However, few reproductive studies have been undertaken in this species with the result that limited laboratory-based scientific information is available. One of the major drawbacks of vervet monkey as a model in human reproductive studies is probably the lack of external indication of ovulation with the implication that monitoring of the menstrual cycle is difficult. In addition, vervet monkey is more susceptible to stress than any other East African primates.
Baboon is an ideal model for human reproductive studies because they closely resemble human in terms of reproductive biology, immunological responsiveness, anti-fertility mechanisms, immuno-pathological reactions and sequel associated with use of vaccines. Like humans, baboons have no breeding seasonality and more importantly, they have an external (overt) indication of the stage of menstrual cycle. The stage of the menstrual cycle in baboon is easily determined by assessing the periannal sex skin. Dramatic changes in colour and size occur throughout the cycle and the degree of inflation (swelling) or tumescence in any individual animal indicates the stage of the cycle. Ovulation is estimated to occur 2-3 days before detergescence (deflation) or the last 2-3 days of maximum tumescence and this appears to be the optimal time for single mating. With regard to pregnancy studies, placenta in baboons is deciduate discoid similar to that in human. * Because baboons are phylogenetically close to humans, they are suitable model for the study of reproductive health issues relevant to humans. Monkeys and humans share similar reproductive anatomies, physiology, immunology, pathology and hormonal cycles. This has enabled scientists at IPR to utilise the baboon for studies aimed at developing male contraceptive vaccines. A new class of birth control methods are required for use by both men and women. These would include immunological-based contraceptives, which are likely to offer advantages over other fertility control methods in terms of efficacy, reversibility and safety and may be more acceptable within the African cultural setting. Other studies currently on-going include development of assisted reproductive technologies such as in-vitro fertilisation (IVF) and studies on the role of endogenous retroviruses on placental development and survival of foetus. The interaction between human contraceptives and human immunodeficiency virus (HIV/AIDS) is an interesting subject, since it has been suggested that because of their effects on mucosal linings contraceptives can potentiate HIV infection. In addition, diseases that are associated with female infertility such as endometriosis, a gynaecological disease characterised by chronic pelvic pain and recurrent pregnancy losses in women is under intense scrutiny at IPR. Studies are aimed at producing simple diagnostic procedures for endometriosis and in partnership with pharmaceutical companies and European collaborators; IPR scientists are testing new drugs against endometriosis. The department is also involved in the development of microbicidal contraceptives to prevent pregnancy and HIV infections. For most of its work, the department receives research funding from International organisations and Agencies including WHO, Drug Companies and Collaborating Organisations and Institutes. Training is an important facet of all the work carried out in the area of reproductive health and training is conducted for postgraduates, undergraduates and post secondary students.
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