This study was designed to compare four different medicinal plants, cinnamon (Cinnamomum verum), cumin (Cuminum cyminum), fenugreek (Trigonella foenum-graecum) and ginger (Zingiber officinale), as natural feed additives with the Doxystin: “Doxycycline HCl 50 mg and Colistin sulfate” (known antimicrobial growth promoter) on plasma biochemical values of broiler chicks includes total protein, albumin, globulin, albumin/ globulin (A/G) ratio and the Alkaline phosphatase activity. Two hundred and forty, (one day-old) broiler chicks were randomly assigned to six groups of similar mean weight each included four replicates of ten chicks. The control group received broilers basal diet. For the treated groups, the basal diet was supplemented with one of the following: the antimicrobial (Doxystin) as 0.5% or one of the spices C. verum, C. cyminum, T. foenum-graecum and Z. officinale as 2%. The results showed significant (P<0.05) increase in the serum total protein and the globulins concentrations in T.foenum-graecum group compared to the control group and other spice treated groups, also the globulins levels were significantly (P<0.05) higher in Doxystin and C. cyminum groups compared to the control group. The serum albumin/globulin ratio was significantly (P<0.05) decreased in all experimental groups compared to the control group.
Treatment with different spices in the present work increased the total proteins and the serum globulins fraction of the blood proteins, albumin remains unchanged and this effect lowered A/G ratio. These findings suggest improved rate of growth and immunity in the broiler chicks. The results also showed no significant difference between the experimental groups and the control group for the serum alkaline phosphatase (ALP) activity. This suggested that no significant liver problem will arise from the use of the spices as treatments