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The aim of this research was to study the effects of seasons (rainy and dry) on the composition of the fatty acids (FAs) in milk of Creole goats in a semiintensive production system. Milk sampling was carried out in the dry season (June) and just after the rainy season (November) in an arid region of Baja California Sur, Mexico. The goat diet was composed of native species it grazed on in the rangeland, as well as hayed forages with some supplements containing approximately equal amounts of sorghum and maize. The results for different types of FAs in goat milk showed that there were no significant differences in saturated, polyunsaturated, branched, and omega-6 FAs, with differences for monounsaturated and omega-3 FAs. In terms of individual FAs, the majority of changes were not significant. The FA constituents showed that significant differences existed for C12:0, C23:0, C14:1 n-5, C14:1 n-7, C18:1 n-9, C18:3 n-3 cis, C22:5 n-3, and-C22:6 n-3, and 2 branched fatty acids, C12:0 iso and C15:0 anteiso. The rest showed a trend of higher quantities of FAs during the rainy season, but it was not significant. In conclusion, goat milk quality as measured by FAs is for the most part very similar year round, independent of seasons in this semiintensive production system.