Causative factors and type of anaemia developed in rabbits following chronic consumption of thermally oxidized palm oil diet

Abstract

Several studies have documented negative effects following consumption of thermally oxidized palm oil on various systems of the body. This study seeks to investigate the effects of long term consumption of fresh and thermally oxidized palm oil diets on markers of anaemia. Eighteen male 5 months old New Zealand rabbits weighing 750-1000 g were used for this study. The animals were divided into 3 groups (n = 6), namely; control, fresh palm oil-fed group (FPO) and thermally oxidized palm oil-fed group (TPO). Fresh palm oil diet was prepared by mixing 15 g of fresh palm oil with 85 g of feed while thermoxidised palm oil diet was prepared by mixing 15 g of thermoxidised palm oil with 85 g of feed. At the end of 6 months of feeding, the animals were fasted for 12 h, after which blood samples were collected via cardiac puncture, under chloroform anaesthesia. The blood samples were then used for the different analysis. Red blood cell count, haemoglobin concentration and packed cell volume for TPO (4.58±0.30 millions mm -3, 14.96±0.92 g dL -1, 33.3±1.92%) group was significantly lower (p<0.05) compared with control (5.45±0.15 million mm -3, 17.26±0.40 g dL -1, 38.88±1.3%). Erythropoietin concentration was significantly lower (p<0.01) in TPO group (7.45±0.83 pg mL -1), compared with control (14.45±2.09 pg mL -1) and FPO (11.63 ±0.68 pg mL -1) groups, (p<0.05). Specific gravity of whole blood in the TPO fed group (1042±1.68) was significantly reduced (p<0.05), compared with control group (1052±1.67). On histology, the TPO fed group showed infiltration of the bone marrow with adipose tissue and reduction in the number of blood forming cells, while the liver in the TPO fed group showed extensive diffuse steatosis. This study has revealed the specific causative factors of anaemia following chronic consumption of thermally oxidized palm oil to be reduced serum erythropoietin, increased RBC hemolysis and damage to the bone marrow and kidneys. The class of anaemia has been identified in this study as normocytic and normochromic type.