Trials on the Use of Gum Arabic for the Control of Experimentally Induced Hyperlipaemia in Donkeys (Equus asinus asinus)

Abstract

Hyperlipaemia is a pathophysiological response to prolonged negative energy balance associated with gross lipaemia. In donkeys, hyperlipaemia was associated with high mortality rates. A series of two studies was conducted to evaluate the therapeutic and/or prophylactic potential of Gum Arabic as antihyperlipidaemic agent. The first study was designed to determine whether treating with Gum Arabic would lower plasma lipids in a group of donkeys with experimentally induced hyperlipidaemia. Three groups each of six male donkeys, 4-10 years of age, were subjected to four days fasting to induce hyperlipidaemia and then they were randomly assigned to receive either 25 or 50g /day orally for seven successive days gum Arabic or left untreated. Following fasting triglycerides level was increased significantly (P<0.05) in the plasma of donkeys in the three groups. Simultaneous increase in Plasma level of cholesterol, urea, creatinine and albumin was also observed in the three groups following fasting. No significant difference was observed in total protein, glucose concentration as well as AST and ALT activities. Treatment of donkeys with gum Arabic with 25mg/day resulted in significant decrease in the plasma level of triglycerides, cholesterol, urea and creatinine. The level of triglycerides in the group treated with 50g/day exhibited no significant decrease and remained at high level up to the end of the experiment. The concurrent decrease in urea and creatinine may indicate a further additive effect in kidney function. Another experiment was conducted to evaluate the prophylactic effect, if any, of gum Arabic against experimentally induced hyperlipidaemia in donkeys. For this purpose, three groups of donkeys each of six were either: drenched with gum Arabic at dose rate of 25 g/day (PG1) or 50 g/day (PG2) for seven successive days, or left without treatment as control group. Animals then were subjected to five successive days fasting. During gum Arabic supplementation triglycerides concentration showed fluctuation with no significant (P>0.05) change. Significant increase (P<0.05) during the 2nd, 3rd, and 4th days of fasting was observed in the control and the PG1, while the level increased significantly (P<0.05) only at the 4th day of fasting PG2 and to a level that was noticed to be lower when compared with the level of the control and PG1. A similar pattern for cholesterol was observed in the control and PG1, where significant (P<0.05) increase was observed at the 2nd, 3rd, and 4th day of fasting; while the significant increase was only observed at the fourth day of fasting in the PG2. The level returned to normal by the end of the experiment. Urea concentration increased significantly (P<0.05) in the three groups during fasting period and returned to normal level by the end of the experiment. ALT activity was significantly (P<0.05) increased during fasting in the control and the first group (PG1), while the increase in the second group did not reach the level of significance. The fluctuation in albumin, creatinine and glucose concentration did not show any significant difference following either administration of gum Arabic or five days fasting. Significant increase in total protein concentration was observed in the first prophylactic group (PG1) during fasting. The level returned to non-significant change by the end of the experiment Significant increase in AST activity was observed only in the second prophylactic group (PG2) during fasting period and at post fasting the level returned to a non significant (P>0.05) change by the end of the experiment. Here it is to be concluded that gum Arabic at dose rate of 25g/day for seven successive days has positive effect in lowering plasma triglycerides level in donkeys with experimentally induced hyperlipidaemia; and that the increase in the gum Arabic dose was not necessary to affect the level of triglycerides in donkeys. Gum Arabic supplementation at dose rate 50 g/day would exert prophylactic effect against experimentally induced hyperlipidaemia in donkeys. Daily intake of gum Arabic at dose rate of 50g/day for seven successive days delayed the increase in triglycerides as well as cholesterol concentration when compared with control group, that considered to be of value in controlling hyperlipaemia. Keywords: Lipid profile, hyper-triglyceridaemia,gum Arabic, donkeys