In this study the effect of Aloe vera leaf gel on absorption of colostral immunoglobulin from intestinal mucosa in new born calves was investigated at 48 h of age(time I) and 72 h of age (time II). Weight gain was assessed until weaning weekly. Thirteen Holestein calves with average 45 kg were divided into two groups, randomly. Daily, 15 ml Aloe vera gel was given to treatment group with colostrum and milk. Blood specimen was collected from jugular vein at both times (I,II). Total protein γ-, globulin, and weight gain were assayed. The result of acetate cellulose electerophoresis showed the level of γ- globulin in treatment and control groups were 1/33 g/dl and 1/25 g/dl at time I that was not significant but correlation between serum protein and gamaglobulin levels was significant in treatment group (r=0/5832, P=0/05) against control (r=0/0141) at time I. Increasing immunoglobulin absorption and also decreased FPT in treatment group (35 %) in comparison with control (44%) could be the cause of significant correlation. At time II, the level of gamaglobalins decreased briefly in treatment group, conversly. The level of serum IgG by sodium sulfite precipitation test revealed a boot 20 % calves had less than 500 mg/dl IgG in serum in treatment group in contrast to control at time II. The more important correlation in treatment group(r=0/7646 P=0/01) than control (r= 0/5404 P=0/05) represented increasing serum non imunoglobulin proteins in treatment group at time II. On the other hand, differences between r2=0/5846 in treatment group and r2=0/2925 in control may be represented modified protein metabolism in consequence of Aloe vera effect on regulation of protein metabolism in treatment group at time II. predicted serum protein concentration at 1 g IgG /dl serum in treatment and control groups at time II and treatment group at time I were approximately 5.8 g/dl. Therefore cutoff value was not affected by use of Aloe vera gel in three groups. This means Aloe vera does not interfere with diagnosis FPT by measurement of total protein concentration in new born calves. Also, the consumption of Aloe vera gel have not significant effect on gain weight until weaning. In conclusion Aloe veragel has favorable effect on the level of gamaglobulin and decreasing of FPT at time I but it has no effect on gain weight in new born calves.
