STUDY ON PHENOTYPIC CORRELATIONS AMONG MILK PRODUCTION AND MILK CHEMICAL COMPOSITION
Keywords:
phenotypic correlations, milk yield, milk chemical components, Romanian Black and White, cowsAbstract
In this study, the phenotypic correlations among quantitative and qualitative
indices of the milk production in Romanian Black and White cows from the
Didactical far Timişoara were studied. Studies were carried out on 125
lactations from 92 cows. Correlations coefficients and their statistical
significance were calculated. Correlations among the milk yield and the yield
of milk chemical components were positive taking values over 0.900, and very
significant (p<0.001). Correlations between milk yield and qualitative indices
of milk (butterfat percentage, protein percentage, lactose percentage, solids
non-fat percentage and total solids percentage) varied between r=-0.002 with
butterfat percentage until r=0.187 with protein percentage, but the values did
not reached the level of statistical significance (p>0.05). Among the
percentage of milk constituents very significant correlations were obtained
(p<0.001), values varied from r=0.427 between butterfat and lactose
percentages to r=0.911 between lactose and solids non-fat percentages.
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