Effect of diets on the dairy potential of cattle in Saharan regions: case of Ghardaïa region (Algeria)

In order to study the impact of diet on the milk potential of dairy cattle in the Saharan context, 83 dairy farms (2150 dairy cows) were surveyed about farm characteristics, feeding practices and milk performance. The results showed the existing of 09 diets with dominance of diets D6, D5 and D2 which indicate the dependance of half of the farms studied on feed concentrate. Average milk yield is 6117 kg/cow/year,which is negatively affected respectively by quantities of UFL required for the production of one kg of milk UFLT/PLR (r = -0.74) and UFL[C]/PLR(r = -0.58). on the other hand, milk yield was positively correlated with green forage area (SF/UGB) (r = 0.3), farm size (SAU (r = 0.26), nutrient intake (PDI/UFL) (r = 0,41 ) and to the amount of ingested dry matter (MST) (r = 0.56). The amount of concentrate consumed was 5.25 ton/cow/year of which the proportion of concentrates according to Part[c]/MST, Part[c]/UFLT and Part[c]/PDIT were respectively 65.1%, 74.8% and 81.2%. The cost of milk production was negatively correlated with SF (r = -0.5), number of cows (r = -0.35), PDI/UFL ratio (r = -0.55) and milk yield (r = -0.52)