The effect of Iranian capripoxvirus vaccine strains on neutralizing antibody titer in cattle

Lumpy skin disease (LSD) virus, Goat-poxvirus (GPV), and Sheep-poxvirus (SPV) are members of genus capripoxvirus (CaPV) and have close genetic similarity. The use of CaPV-vaccine strains would be useful to protect the cattle against LSD. This study aimed to compare the neutralizing antibody titer of Iranian heterologous sheep pox and goat pox vaccines against LSD in cattle. A total of 100 calves was vaccinated with Gorgan-GPV and Ramyar-SPV vaccines on separate farms. Neutralizing antibody titer and side effects of vaccines were evaluated at days 14, 28, 45, 90, and 180 post-vaccination. The mean of rectal temperature in SPV was higher than GPV and persisted for up to 3 days. Also during the onset time of fever, ocular and nasal discharge were observed, whereas in the GPV and control group no clinical signs were observed. In each vaccinated group, the first detectable antibody titer was after 14 days and rose to peak at 28-45 days post-vaccination, then it decreased in the following days. Although, the mean of the neutralizing index (NI) titer between GPV and SPV was relatively similar and there was no statistically significant difference (p > 0.05) at all days of the experiment, but in GPV the titer appeared slightly higher than SPV and reached to protective level (NI ≥ 1.5) on day 45 post-vaccination. There was a high antibody titer (Log101.07) in the day 180 post-vaccination. The results showed that GPV vaccine because of the induction of the protective level of antibody titer, and persisting within  a long period for up to 180 day post-vaccination, has a good immunogenic response, so is considered a suitable vaccine to control LSD.