Résumé
Fifty mature albino male rats were divided equally into five groups. The first group [control group] was fed on a control diet, in the 2nd group and 3rd group, about 20% and 40% of the carbohydrate in the control diet were substituted by fish oil, but in the 4th, and 5th group beef fat substituted the carbohydrate in a ratio of 20% and 40% respectively. After two weeks of feeding, the animals were sacrificed, the plasma and liver samples were obtained and kept at -20 till analysis. PLasma levels of glucose, free fatty acids [FAAs], total lipids and insulin were measured, moreover, liver FFAS and total lipids were measured. The results indicated that the plasma glucose level was increased by 73% in groups [4 and 5] fed on diets containing 20% and 40% beef fat, while [FFAs] in plasma significantly increased in the same groups. On the other hand, plasma [FFAs] level revealed 40% and 50% decrease in the animal groups fed on the diets containing 20% and 40% fish oil respectively. The plasma insulin levels were significantly increased by 109% and 135% in the same respective groups. In the animals fed on the diet containing 40% fish oil, the total plasma lipids showed a significant decrease of 32%. But the level showed a significant increase of 40% and 53% in the animal groups fed on the diet containing 25% and 40% beef fat respectively. The total lipids in liver tissues was significantly increased in all tested groups. It was concluded that, feeding on the beef fat "a hyperlipidaemic fat" resulted in increased plasma glucose, FFAs and total lipids concentration without any significant changes in the insulin level. On the other hand feeding on fish oil resulted in a decrease in plasma FFAs and total lipids with significant increase in insulin level without any changes in plasma glucose in adult male albino rats