Effect of Aloe vera gel and conjugated linoleic acid on performance, blood metabolites and immune parameters in sucking Holstein calves

This study was conducted to evaluate the effect of Aloe vera gel and conjugated linoleic acid supplement feeding on performance, blood metabolites and immune parameters in Holstein calves in a completely randomized design with a 2×2 factorial arrangement. This study was carried out using 24 male and female Holstein calves (with average age of 1-10 days and 38±8 kg weight) with four treatments and six replications for 60 days. The treatments were: (1) basal diet including starter and whole milk (control), (2) basal diet + 250 mg/kg body weight Aloe vera gel, (3) basal diet+20 g/kgDM complementary conjugated linoleic acid (CLA) and (4) Basal diet+250 mg/kg body weight Aloe vera gel+20 g/kgDM of CLA. The Dry matter intake, weight gain, feed conversion ratio, blood parameters and immune and health factors were measured. Results showed that there were no significant differences between the control and other groups in terms of feed intake and performance of Holstein calves. The interaction effect of Aloe vera gel and CLA was significant on blood glucose concentration and calves receiving 250 mg Aloe vera gel had the lowest glucose concentration (88.33 mg/dL) (P>0.05). On the other hand, the effect of time on white blood cell, lymphocyte and monocyte was significant (P<0.05) and using 20 g CLA increased blood monocyte (5.33%) compared with no CLA treatments (3.58%; (P<0.05). In general, the interaction effect of aloe vera gel and CLA supplementation was not significant on performance and health status of Holstein calves.