EFFECT OF MATERNAL CONTACT, HOUSING SYSTEM AND PROBIOTICS SUPPLEMENTATION ON SOME PLASMA METABOLITES AND THYROID HORMONES LEVELS OF CAMEL-CALVES DURING WEANING PERIOD

There are some factors influence on productive performance and physiological responses of camel-calves during weaning period. Mothering is an important factor for maintain the biological functions, immune-competence and calf survival. At weaning, calves were housed either with their dams or separated from their dams. Therefore, this study performed to investigate the effects of calf-dam contact system [completely contact system, (CCS) vs. completely separation system, (CSS)]; housing system [grouping, (G) vs. individually, (I)] and probiotics supplementation [control, (C) vs. probiotic, (P)] on some plasma biochemical parameters and thyroid gland activity of Maghreby camel-calves for 28 days period. Twenty female of camel calves aged 280 days with initial live body weight (LBW) of 236.76 ? 0.224 kg were used. The study was carried out at Maryout Research Station of the Desert Research Center (DRC), Cairo, Egypt. Weekly blood plasma samples was analyzed for plasma total proteins (TP), albumin (A), plasma urea nitrogen (PUN), total cholesterol (CHO), triglycerides (TG), glucose (GLU), alanine amino transferase (ALT), aspartate amino transferase (AST), alkaline phosphatase (ALP), lactate dehydrogenase (LDH) concentrations and thyroid gland activity (T3 and T4 hormones) were determined. Results indicated that calf-dam contact system as Psychological stress and housing system as social stress, influenced significantly (P<0.05) on plasma TP, G, PUN, CHO, TG and GLU concentrations whereas the presence of dam and grouping housing system has the higher levels of these parameters compared with absence of dam and individually housing system. Calves housed under completely contact with their dams or grouped housing system has higher (P<0.05) concentrations in circulatory T3 and T4 hormones compared with calves separated from their dams or individually housed during weaning period, while probiotics supplementation had no statistically significant effect on circulatory T3 and T4 levels. Interactions of treatment and sampling time (P < 0.01) were detected for plasma T3 and T4 levels under all three experimented factors. Liver enzymes (ALT, AST, ALP and LDH) activities were unaffected significantly (P>0.05) by calf-dam contact system, housing system and probiotics supplementation.It be concluded that camel-calves were more sensitive to the effects of calf-dam contact and housing system during weaning process. The results suggest that the calves remained with their dams and group-housing system can be the better as anti-psychological and social stressors than those separated from their dams or individually housed ones as management system at weaning process.