Nutritive physiological effect of dietary fats in growing swine rations. 3. Effect of sunflower and coconut kernels on protein and fat retention, backfat fatty acid pattern and various blood parameters in piglets

Two groups, each of 9 castrated male piglets of the German Landrace breed, body weight 13-29 kg, were fed ad libitum for a 5 week period in order to determine the influence of the fatty acid composition of the dietary fat on protein and fat retention. The concentrations of urea, insulin, glucose, free glycerol and triglycerides were also determined. That fat in ration I (derived from 27% sunflower seed) contained 50% linoleic acid while that of ration II (derived from 12,5% coconut kernels) had a maximum lauric acid content of 41,8%. The relationship between digestible crude protein and ME-content was calculated to be similar in both rations. In addition protein quality was calculated to be similar in both rations. Protein deposition was determined from both nitrogen and comparative slaughter procedures. The results can be summarized as follows: The animals fed ration I had a higher daily ME-intake and growth rate than those fed ration II, although no great difference was observed in ME required per kg body weight gain. The efficiency of protein utilization was significantly better in group I and this was associated with a lower blood urea concentration. The concentrations of insulin and glucose in the blood, measured before as well as 20, 45, 60 and 120 minutes following feeding, showed little differences between the groups. The triglyceride concentration measured before and 1 and 5 hours following feeding was significantly higher (p less than 0,01) in group II. There was no significant difference in the protein and fat content of the body as well as in the daily protein and fat deposition. The fatty acid composition of the back fat was significantly influenced by the fatty acid pattern of the dietary fat. In group I the linoleic acid content was 3,6 times higher and the lauric- and myristic acid content 11,7 times lower compared to that of group II.