Aneela HAMEED, Muhammad FaqirANJUM, Tahir ZAHOOR, Zia UR-RAHMAN, Saeed AKHTAR, Majid HUSSAIN

Effect of oxytocin on milk proteins and fatty acid profile in Sahiwal cows during lactation periods

Bovine milk, a rich source of proteins and fatty acids, has a beneficial impact on physicochemical and organoleptic properties. The current study was planned to identify oxytocin s effects on protein and fatty acid profiles of cow milk (the Sahiwal breed) at various lactation stages (early, middle, and late) under a controlled atmosphere and feeding inputs. Examination of milk protein and fatty acid profiles by urea polyacrylamide gel electrophoresis and gas chromatography-mass spectrometry respectively revealed the significant effect (P < 0.01) of oxytocin during the cow s lactation stages. In electrophoretic patterns, casein (αs1-CN, αs2-CN, β-CN, and k-CN) and whey protein fractions (Ig, BSA, β-Lg, and α-La) appeared as low-intensity bands in oxytocin-injected milk when compared to the control. Reductions in concentrations of fatty acids C16:0 (25.00%) and C18:1 (21.60%) were observed in oxytocin-treated milk as compared to the control group (29.30% and 29.10%, respectively) at late lactation.

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