Lipid status, paraoxonase-1 activity and metabolic parameters in serum of heifers and lactating cows related to oxidative stress

• Published in: Research in veterinary science 2011-04, Vol.90 (2), p.298-300
• Main Authors: Antončić-Svetina, M., Turk, R., Svetina, A., Gereš, D., Rekić, B., Juretić, D.
• Format: Article
• Language: English
• Subjects: Animal reproduction; Animals; Aryldialkylphosphatase - genetics; Aryldialkylphosphatase - metabolism; Cattle; Cattle - blood; Cattle - metabolism; Cholesterol; Dairy farms; Diet; Energy Metabolism - physiology; Female; HDL; Heifers; Lactating cows; Lactation - physiology; Lipids - blood; Oxidative stress; Oxidative Stress - physiology; Paraoxonase-1; Serum lipids; Veterinary medicine
• ISSN: 0034-5288; 1532-2661
• DOI: 10.1016/j.rvsc.2010.05.022

The objective of this study was to investigate serum lipids, metabolic parameters and activity of the anti-oxidative enzyme paraoxonase-1 (PON1). The study was conducted on non-pregnant heifers with optimal health status and on healthy dairy cows in the period of intensive lactation, assuming that the energy and metabolic demands during lactation reduce anti-oxidative protection. Total cholesterol and HDL-cholesterol concentrations were significantly higher ( P < 0.05) in lactating cows than in heifers. Bilirubin concentration and γ-glutamyltransferase (GGT) activity were also significantly higher in lactating cows ( P < 0.05), indicating increased hepatic efforts of cows to meet energy requirements for lactation. Significantly lower PON1 activity and PON1/HDL ratio in lactating cows compared to heifers ( P < 0.05) showed that metabolic efforts during pregnancy, parturition and lactation influence PON1 activity due to oxidative stress. Concurrent increase in total and HDL-cholesterol during lactation indicated that the HDL particle is a major carrier of cholesterol in cows.