Blood lipids and liver fatty acid composition in brown hares (Lepus europaeus) from two different Croatia habitats

The purpose of the study was to examine the concentration of blood lipids and fatty acid composition of liver in autochtonous brown hares (Lepus europaeus Pallas, 1778) from two different ecological habitats in Croatia. The 31 blood and tissue samples were collected during the regular hunting operation in November at two different hunting grounds, island Vir (area 1) located in mid Dalmatia and Međimurje region (area 2) situated in the continental north west Croatia. Both areas are naturally ihabited with brown hares. The body weights (BW), the liver fatty acid composition, as well as plasma total cholesterol and tryglicerades concentrations were determined during the same months of hunting period. The significant area differences were observed in body weight and fatty acid composition of liver tissue. The significantly higher BW (3, 68 kg vs. 2, 77 kg) and proportion of miristic (C14:0) and palmitic acid (C16:0) was determined in the liver of hares from area 2, whereas significantly higher content of margaric (C17:0) and stearic acid (C18:0) was observed in the liver of hares inhabited area 1. No area differences were observed in total plasma cholesterol and tryglicerades concentration. The Spearman correlation coefficient revealed the positive correlation of total plasma cholesterol level and stearic and margaric acid (r=0, 94 ; p<0, 05), and negative correlation of total plasma cholesterol with palmitoleic acid (r= - 0, 83 ; p<0, 05) in livers of hares. The significant differences of liver fatty acids composition in hares from two different habitats may indicate the difference in fatty acid metabolism regarding the food niches they occupy, but also might have been indirectly related to population density and predation risk that should be further studied.