Reproductive well-being and performance of farm animals is largely dependent on their nutritional status, which is often less than optimum in developing tropical countries. More often than not, they are malnourished, particularly with regards to micronutrients. Evidence was presented to show that because these micronutrients are involved in such functions as intracellular detoxification of free radicals, synthesis of reproductive steroids and other hormones, carbohydrate and protein and nucleic acid metabolism, their deficiencies and/or excesses may impair spermatogenesis and libido in the male, fertility, embryonic development and survival, post-partum recovery activities, milk production and offspring development and survival. A plea was made for intensified research efforts, farmer education and quality control of vitamin-mineral pre-mixes, in order to improve micronutrient nutrition, and, consequently, the reproductive performance and overall productivity of farm animals in developing tropical countries.