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In order to enhance our knowledge of milk sheep rationing, 30 Sarda primiparous ewes, for which single birth was diagnosed<br />by ultrasonography prior to lambing, were divided into two homogeneous groups (L-NSC and H-NSC) and fed isoproteic<br />diets containing different amounts of non-structural carbohydrates (NSC, 36 vs 40 % DM). The lambs were<br />weighed both at birth (between February and March 2002) and at sale (about one month later) in order to estimate milk<br />produced by their mothers during the lactation period, by using a specific equation developed on Sarda ewes. Individual<br />milk yield and quality were then monitored monthly until the ewes dried off (July 2002). Our results showed that group<br />H-NSC (which received the diet with the highest NSC content) was associated to the highest milk yield (P<0.01) during<br />the suckling period. In contrast, in the milking period group L-NSC showed significantly higher (P<0.05) mean milk yield<br />(996.2 vs 899.8 g/d) and fat and protein corrected milk yield (979.6 vs 877.7 g/d). Dietary treatments did not significantly<br />affect milk composition.<br />In conclusion, considering the milk production of each group as a function of the lactation month, group H-NSC had its<br />best performance during the first two months of lactation, while group L-NSC was more productive during the remaining<br />months. Also the percentage of protein, fat and casein of the milk during milking showed a similar trend. While the latter<br />parameters were higher in the H-NSC group during the first two months of milking, from the 4th control onward higher<br />levels were observed in the L-NSC group. These results suggest, at least for Sarda primiparous ewes, the adoption of<br />diets with different contents of non-structural carbohydrates according to the productive period (40 %, DM basis, in the<br />first two months of lactation, 36 %, DM basis, in subsequent months).