Anti-fertility Activity of Ingestion of Nigerian Bonny Light Crude Oil Contaminated Feed in Male Rat Reproduction: A Possible Hypothalamo- Pituitary Axis Mechanism

Over the past decades, particularly in the Niger Delta region of Nigeria, oil and gas flared and/or oil-spilled microscopic pathogens are continually introduced into the environment and the immediate or short term impact on humans (as well as wildlife) can hardly be noticed except when damage has been done. This study therefore investigated the potentially dangerous adverse reproductive fertility impact of continuously exposure to short-term low-levels of Nigerian Bonny Light crude oil (BLCO) contaminated feed. Virgin fertile male rats of reproductive age were exposed to 0.3ml, 1.0ml and 2.5ml of BLCO mixed with 20g of rat feed respectively for two weeks. Thereafter, one group were mated with fertile virgin female rats also of reproductive age till parturition. Whereas another group were sacrificed and the testes were removed for histological examination, and hormonal profiles and semen qualities were analysed. Our results showed histologically no detectable differences in the testicular architecture, but dose-response decrease association between the crude oil polluted diet, hormonal and semen parameters, growth rate and pups with low birth rate compared with control (p < 0.05). It is suggestive that the hypothalamus part of the brain may be “turned off” when triggering the pituitary glands to produce sex hormones. More so, the environmental pollutant probably acted in the control of reproduction fertility by interfering with the feedback mechanisms on the hypothalamicpituitary-gonadal axis, thereby bringing about oxytocin-like type of contractions of the uterus as in the females. The values of the calculated reproduction indices indicated that BLCO adversely affected reproductive fertilities-sexual life quality-sperm quality and their productions as well. The significance of the environmental pollutant induced reproductive fertility hazards is discussed.