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Background and Aim: Equine herpesvirus-1 infection in horses causes a wide range of manifestations affecting the respiratory tract. The virus can cause serious economic losses through sporadic abortion in pregnant mares, perinatal death, respiratory disease in young foals. This study was designed to prepare inactivated equine herpesvirus-1 (EHV-1) vaccine using both 0.005 M binary ethylenimine (BEI) and 0.0006% formaldehyde (FA) to decrease the use of BEI and provide a good immunological response. The efficacy, safety, and duration of immunity of the prepared inactivated EHV-1 vaccine were evaluated. Materials and Methods: The prepared FA/BEI-inactivated EHV-1 vaccine was adjuvanted with Alhydrogel and then evaluated by inoculation into guinea pigs, followed by comparison with the commercial inactivated EHV-1 vaccine. These two vaccines were evaluated by testing the safety and immunogenicity in horses classified into two groups. Group A was vaccinated with two doses of the prepared vaccine at a 4-week interval, while Group B was vaccinated with two doses of the commercial vaccine only. Anti-EHV-1 antibodies were detected in horse serum using enzyme-linked immunosorbent assay (ELISA) and virus neutralizing test (VNT). Results: Regarding the time required to inactivate EHV-1 vaccine, this was decreased using 0.005 M BEI and 0.0006% FA from 24 to 8 h. ELISA in Group A horses demonstrated a significant increase in EHV-1 antibody titer at 2 weeks after the booster dose compared with that for the pre-booster one, from 485 to 855 antibody titer, which then peaked at 1240 in the 3rd month post-vaccination; after that, it began to decline gradually until the 6th month. Meanwhile, in Group B, the ELISA reading increased from 420 to 790 and then peaked at 1215. The VNT mean in Group A increased from 1.1 to 2.5 within 2 weeks after administration of the booster dose, while in Group B it increased from 0.8 to 2.1. Moreover, ELISA in Group A pigs indicated mean antibody titers at the 3rd week post-inoculation of 576 for Group A and 554 for Group B. Conclusion: The inactivated EHV-1 vaccine, with fewer chemicals, was prepared in a shorter time. It is safe and also more potent to protect horses for up to 6 months against EHV-1 infection than the commercially produced vaccine.

A total of 150 pigeons of 45 days old was used and divided into three groups; the first one was vaccinated with tissue culture adapted pigeon pox vaccine (TCAPPV), and the second was vaccinated with egg adapted pigeon pox vaccine (EAPPV) and the third as a nonvaccinated control group. Birds were observed for ten days postvaccination (DPV) for the presence of takes. Cellular immunity was detected by lymphocyte proliferation assay on the whole blood for 21 DPV, and serum samples were collected weekly. The level of induced antibodies was detected by the neutralization test for six months postvaccination. Twenty pigeons of each group were challenged by virulent pp virus at 28 th DPV Takes were recognized at the site of vaccination at 4 th DPV and increased to the maximum at7 th DPV to reach 90% for TCAPPV and 98% for EAPPV. The peak of the cellular immunity by lymphocyte proliferation assay was at the 12 th DPV when TCAPPV recorded 1.534 and EAPPV 2.037. Protection was 90% for TCAPPV and 100% for EAPPV. The peak of neutralizing index (NI) at 35 th D.P.V for both vaccinated groups; It was 2.75 for TCAPPV and 3.25 for EAPPV. Both vaccines are still potent to the end of examination at the 6 th month when NI was 1.5 for TCAPPV and 2.0 for EAPPV. This result shows that both eggs adapted PP and tissue culture PP vaccines are efficient in the protection of pigeons in Egypt despite the egg adapted vaccine is more preferable.

In different countries and sometimes within a country, various live attenuated vaccine have existed from time to time for capripox with varying degrees of protective efficacy. An experiment applied on eight groups of susceptible calves, were individually inoculated intradermally (I/D) or subcutaneously (S/C); In order to pinpoint the optimum program of vaccination against lumpy skin disease in the tail fold with one of the alternative vaccination programs by using attenuated Lumpy skin disease (LSD) vaccine, attenuated Romanian sheep pox (RSP) vaccine and inactivated LSD vaccine (separate; simultaneous or successive); in an attempt to obtain a safe and protective vaccination regem for cattle against lumpy skin disease. The humoral immunity was checked out by serum neutralization test (SNT) and enzyme linked immunosorbent assay (ELISA) for 6 months post inoculation, while the cell mediated immune response was performed by the hypersensitivity reaction at the inoculation site after I/D inoculation with 0.5 ml of attenuated undiluted LSD vaccine and its results corroborate the humoral results. The results of humoral and cellular immune response proved that successive vaccination of cattle with live attenuated RSP vaccine prior to the inactivated LSD vaccine create relative acquired immunity subsequent to the homologous live attenuated LSD vaccine and overcome the immunological effect of the other used vaccines. Our results nominate the homologous attenuated LSD vaccine (GP1) and successive vaccination (GP4&5) with attenuated RSP vaccine before inactivated LSD vaccine for absolute protection of cattle from LSD. It was concluded that the successive vaccination (with attenuated RSP vaccine before inactivated LSD vaccine) is considered more safe and avoid viral reversion and transmission of the virus by the blood feeding arthropods.

The experiment applied on four groups of calves, each of four calves. Three calves from each group were vaccinated with one of the following attenuated vaccines: Lumpy skin disease vaccine (LSD), Romanian sheep pox (RSP) vaccine, Held goat pox (HGP) vaccine and dual (bivalent) vaccine of SPV and GPV. All vaccines were evaluated by estimating the cellular immunity using lymphocyte blastogenesis measured by XTT assay, and humeral immunity using serum neutralization and ELISA tests of vaccinated calves. The NI coincided with the ELISA antibody results and corroborated the results of cell mediated immunity which demonstrated the capacity of LSD and dual vaccines to induce immune response higher than SP vaccine and GP vaccines. In conclusion, the current study proved that the LSD and dual vaccines were highly immunogenic than the RSP and HGP vaccines, and dual vaccine could be safely used for vaccination of cattle against lumpy skin disease.