Comparative Analysis of Milk Quality Collected from Holstein Cows and Sicilo-Sarde Sheep Breed in Tunisia

Abstract

The objective of this study was to compare the quality of milk produced from Tunisian Holstein cows and Sicilo-Sarde ewes during their milking period. The experience concerned 80 Holstein (means age 5.2 years; mean weight = 530 kg) and 54 of Sicilo-Sarde ewes (mean age = 6 years; mean weight = 45 kg). The milk samples was taken from the morning and the afternoon milking and added with potassium dichromate. Refrigerated samples were used to determine milk content in fat (MG) and protein (MP) using Milkoscan 4000 after 24 hours of conservation for both cows and ewes. ANOVA was carried using SAS software (version 1997). The results showed that for cows the mean rate of fat (MG) and protein (MP) was respectively 3.3 ± 0.5 % and 3.4 ± 0.5 %. However, for ewe MG and MP were respectively 7.3 ± 0.7 % and 6.3 ± 1.1 %. We found also that the milk component in MG and MP cow’s varied during the milking period (p <0.05) compared to the milk ewe’s which present only a variation in MG component during the milking period (p <0.05). Besides, the total milk production for ewes was affected by the sex of foetus and the rank of milking (p <0.05). We conclude that the milk quality of Tunisian Sicilo-Sarde ewe contains rates of fat and protein greater than those in Tunisian Holstein cows. The chemical quality of the two kinds of milks is also affected by the stage of lactation. Moreover, milk ewe production is also affected by the sex of fœtus and the rank of milking.