EFFECT OF ASCORBIC ACID ON ERYTHROCYTE OSMOTIC FRAGILITY OF YANKASA SHEEP SUBJECTED TO 12-HOUR FEED AND WATER DEPRIVATION DURING THE HOT-DRY SEASON

Abstract

Study was conducted to evaluate changes in erythrocyte osmotic fragility (EOF) in Yankasa sheep, subjected to 12-hour feed and water deprivation during the hot-dry season. Sixteen sheep of both sexes, aged 1-2 years and weighing 12-25 kg served as subjects. Eight of the sheep were given vitamin C (ascorbic acid, AA), dissolved in 25 ml of distilled water per os, and deprived of feed and water for 12 hours, while eight others were deprived of feed and water for 12 hours only, without prior AA administration. Blood sample (1 ml) was collected from each sheep from the jugular vein before AA administration and/or 12-h feed and water deprivation, using standard aseptic procedures. into test tubes, containing sodium citrate. The EOF was determined spectrophotometrically. The percentage EOF rose as the percentage concentration of NaCl in the solution decreased in the sheep before they were deprived of feed and water. The haemolysis decreased predominantly in the sheep administered with AA after the 12-h starvation. In the sheep subjected to only 12-h of feed and water deprivation, the percentage EOF rose with a decrease in concentration of NaCl in the solution at 0.5% NaCl concentration. The EOF after the 12-h feed and water deprivation in the group administered with the AA did not differ significantly (P>0.05), when compared with that of the control group. The findings of the study showed that sheep subjected to nutritional stress of feed and water starvation may be susceptible to increased haemolysis. The increased EOF recorded in the study, especially at 0.5% NaCl concentration, demonstrated that the EOF test may be a valuable diagnostic tool in the determination of feeding status of animals. In conclusion, 12-h feed and water deprivation increased EOF in sheep, and the EOF test may be of value in the diagnosis of feed and water deprivation in sheep during the hot-dry season in the Northern Guinea Savannah zone of Nigeria.