Milk quality of Assaf ewes raised in central Italy (Tuscany)

Introduction: The demand from outside Italy for Italian cheeses made from sheep milk has recently increased. Due to the agricultural productivity crisis, thousands of dairy farms have closed down. In the farms that have remained, there has been a tendency to increase the average milk production. Thus, in Italy there has been a recent increase in the importation of foreign high-yielding sheep breeds. Aim: this study focuses on the Assaf breed imported from Spain, which is being used to replace traditional breeds. The milk yield and quality from the Assaf sheep were monitored during lactation. Materials and methods: Ten pluriparous Assaf ewes underwent milk sampling. Milk quality, fatty acid composition and coagulation properties were analysed from day 20 to day 170 of lactation. Results and discussion: The Assaf sheep showed a high production capacity (about 1.3+0.50 litres / day, on the average) but lower percentage of fat and protein than Assaf reared in other Mediterranean Countries and than local breeds. The coagulation properties (k20 and a30) were better at the end of lactation (k20=1.37 min, a30=36.51 mm). In this phase, the increase in saturated fatty acids and medium chain fatty acids, the decrease in monounsaturated, and saturated: unsaturated fatty acid ratio, indicated a poorer milk nutritional quality in this period. Conclusions: We confirmed the high productivity of the Assaf sheep. The nutritional quality of its milk fat seems better at the beginning of lactation when less saturated, and more monounsaturated fatty acids are present in the milk. Furthermore, higher protein and better coagulation properties of the milk were observed at the end of lactation