In this study, groups of 150 brucella free white Swiss mice, were inoculated with different oily adjuvanated brucella melitensis subunit vaccines alone or both and then were challenged with Br. melitensis virulent strain for the evaluation of the immune response of each subunit vaccine which was judged by testing this potency through spleen to body weight ratio and the number of brucellae per gram spleen. Also two groups of brucella free guinea pigs were inoculated with a combination of different oily adjuvanated Brucella melitensis subunit vaccines combined with either live attenuated Br. abortus strain 19 vaccine, inoculated conjunctivally or RB51 vaccine injected subcutaneously. Then the animals were challenged with virulent Br. melitensis strain. Humeral and cell mediated immune responses were evaluated. The shedding of the vaccinal strains in the different body secretions was detected along the whole days of the experiment. Eighteen serum samples were collected from occupational group working in the vaccine production and application for serological examination. It was found that the protection level in the different mice animals groups was 70%, while in the vaccinated guinea pigs vaccinated with the combined oily adjuvanated Br. melitensis subunit vaccine combined with strain 19 vaccine, was 90%, while in those combined with RB51 vaccine, the protection level was 85%. In addition, no vaccinal strains were detected in the different body secretions of the vaccinated animals along the whole days of the experiments. Only two cases of the occupational group were positive.

A B S T R A C TTen female local breed cows proved to be brucella free (six of them were pregnant, parturated and lactate during the experiment time) were subdivided into two subgroups, the first one vaccinated with combination of HS and OMPs subunit vaccines combined with conjunctival vaccination with Br. abortus strain 19 vaccine and the second group was vaccinated with combination of HS and OMPs subunit vaccines beside vaccination with Br. abortus strain RB51 (S/C). From first day post vaccination to 60 days, saliva, vaginal discharge, fecal and milk samples were collected and examined for the presence of the vaccinal strains. Also, blood samples were collected from vaccinated animals and the serum tested serologically using RBPT, MAT and ELISA. In addition, cell mediated immune response was evaluated using Brucellin test. The results revealed that no vaccinal strains was detected in the different body secretions and the humoral immune response of vaccinated cows reached its peak at the 4 th week post vaccination then decreased gradually and disappeared at the end of the 10 th week. Also, cell mediated immune response revealed that cows vaccinated with the combination of HS and OMPs subunit vaccine combined with conjunctival vaccination with Br. abortus strain 19 vaccine showed remarkable increase in the cell mediated immune response in comparison with in cattle vaccinated with the same combination beside subcutaneous vaccination with Br. abortus strain RB51.