comparative study of probiotic, acidifier, antibiotic growth promoters and prebiotic on activity of humoralimmune and performance parameters of broiler chickens

the aims of this study were the comparative study of probiotic, acidifier,antibiotic growth promoters and prebiotic on activity of humoral immune and performance parameters of broiler chickens.500 one day old male broilers (308 ross strain) were divided into 5 groups: a, b, c, d and e. each group with equal numbers of male included 4 replicates (25 chicks per replicate). group a was as control and the other groups were administrated with distinct dose of drugs, comprised: virginamycine 150 gr/ton, protexin 100 gr/ton, salkil 6 kg/ton, immunoval 1 kg/ton, respectively. 40 broilers were selected from each group randomly and performance parameters such as weight, mortality, amount of grain for consumption, feed conversion rate (fcr) were calculated by means of scale and reference formula. moreover, at three time points (9th, 17th and 24th days) about 1 cc of blood was taken from broilers’ brachial vein, within each of the five groups. laboratory analysis conducted on blood samples featured hemagglutination inhibition (hi) test performed on sera and humoral immunity assessed as antibody production to newcastle disease virus. the results showed that the group c and the group e were the best groups in terms of the performance parameters and the hi rate.