An update on oestrus synchronisation of goats in Nigeria

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This review is aimed at providing information on current status of oestrus synchronization as a management tool in goats in Nigeria. Oestrus synchronisation is a reproductive tool that enables goat farmers breed their animals within a short pre-determined period. The principle of oestrus synchronisation is chiefly the control of the luteal phase of the oestrous cycle and two basic mechanisms are employed. These include the use of prostaglandins or its analogues to shorten luteal life/induce premature luteolysis or the use of exogenous progesterone to prolong luteal life, thereby simulating the activity of natural progesterone produced by the corpus luteum. The latter is advantageous where the reproductive status of the flock is unknown. However, the former is easy to apply and only effective in cycling animals. Pharmaceutical products that have been employed in ES protocols in Nigeria include Lutalyse?, Estrumate?, EstroPLAN?, Fluorogestone acetate?, Sil-Oestrus?, Medroxyl-progesterone acetate?, Synchromate B?, PMSG?, and more recently, the Controlled Intal Drug Release? (CIDR) devices. Over the last three decades, many attempts have been made at assessing the response of goats to various oestrus synchronisation agents and protocols in Nigeria. However, the low availability of these pharmaceutical agents and cost preclude the widespread use of oestrus synchronisation technique in goat production. The inclusion of gonadotrophins in oestrus synchronisation protocols have been reported to improve oestrus responses in goats, while season has been reported to influence the efficiency of oestrus synchronisation programmes. Increasing the dose levels of exogenous hormones in oestrus synchronisation protocols has caused variable and sometimes inconsistent effects. The effects of combining the male stimulus with exogenous hormones, seasonal variation, extra-label use of products and short-term nutritional manipulation on oestrus responses in goats require further evaluation. It is concluded adoption of oestrus synchronisation practice portends enhanced goat production in Nigeria.
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