| Sumario: | A review of genetic and environmental influences on the growth of sheep and goats in West and Central Africa shows that the effects of year, season, month, type of birth, flock, parity, ewe/ doe and breed are important. Most of the work has been on sheep. The effects of year, season and month of birth are expressed through their influence on feed availability for dams and their progeny. The season and month of birth effects” roll ” with regions. While effects of year and season of birth can be noticeable up to 12 months of age, month of birth effects diminishes at about 5 months. Flock differences are important. Ewe effect is important up to about 12 months of age. While the effect of parity disappears before 12 months, the effects of type of birth and sex are still very noticeable up to 2 years at least. Breed effects are important up to 5 months of age, the oldest age studied. However, few studies have involved more than one breed. Estimates of heritability of body weight at various ages were moderate. Estimates of genetic correlations between birth and 4 months weights and between 4 month and ....... month weights were medium but had large standard errors. From this review, it is evident, that goats have not been given as much attention as has been given sheep. Future work should supply information on genetic and non-genetic factors influencing the growth of goats. For both species, attention should be given to breed evaluation on a comparative basis. The need for genetic parameter estimates cannot be over emphasized. If informed designing of breeding programmes is to be made, the availability of required genetic and non-genetic factors influencing the growth of small ruminants in West and Central Africa is imperative.
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