Phenotypic correlations among egyptian buffalo milk production and its major chemical constituents

Nine thousand lactations were used in this work to study the phenotypic correlations among milk production and some of chemical constituents of milk of the Egyptian buffaloes. With regard to the milk yield and its components, all of the correlation coefficients were positive and highly significant (P 0.001), with the exception of coefficients between milk at 1st-lactose and milk at 2nd-fat (P 0.01). The given milk yields and the percentage of its components showed that all of the correlation coefficients were negative and low, with the exception of those between milk at 1st- lactose and total solids (r=0.020 and 0.037), respectively, milk at 3rd-fat and total solids (r=0.066 and 0.004), respectively, milk at 4th-fat (r=0.002), milk at 5th-protein and solid non-fat (r=0.037 and 0.271), respectively. A statistically significant (P 0.05) positive correlation between milk at 5th and lactose (r=0.377*) was recorded. All of the correlation coefficients were positive and highly significant (P 0.001) between daily milk yield and its components, while negative coefficients were noticed among the percentage of fat-protein, lactose and solid non-fat contents (r=-0.131, -0.177 and -0.185), respectively, protein-lactose (r=-0.216), lactose-total solids (r=-0.213).