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Foot-and-mouth disease (FMD) is an economically important contagious disease of livestock mainly cattle, buffalo, sheep, goats, and pig. There is limited data available on pathogenesis of foot and mouth disease in goats. In the study, the sheep and goats were infected experimentally with a serotype O foot-and-mouth disease virus by different challenge routes. The sheep and goats challenged by coronary band route and coronary band and intra-dermo-lingual route exhibited FMD clinical signs at 2–5 days post challenge. Whereas intra-dermo-lingual challenged sheep and goats did not exhibit FMD clinical signs. Live virus could be isolated from blood of infected sheep and goats at 2–5 days post challenge. Viral RNA could be detected from blood of infected sheep and goats at 1–10 days post challenge. The neutralizing antibody titre was detected at 10 days post challenge and maintained up to 35 days post challenge in all infected sheep and goats. Non structural protein (NSP) antibodies were detected as early as 5–10 days post challenge and remain positive up to 35 days post challenge in the infected sheep and goats. In conclusion, the pathogenesis of sheep and goats with serotype O foot and mouth disease virus by different challenge routes could be demonstrated.

Abstract: Serology is used to predict vaccine induced protection against challenge with a heterologous strain of the same serotype of foot-and-mouth disease virus (FMDV). To evaluate the accuracy of such predictions, we compared the protection afforded to cattle vaccinated with the O1 Manisa strain of FMDV against challenge with either a homologous (O1 Manisa) or a heterologous strain (O1 Campos). Serology by virus neutralization test (VNT) using O1 Manisa antiserum predicted an acceptable protection against such a challenge. Two experiments were carried out to compare the results for consistency. A total of 78 naïve cattle were vaccinated with different antigen payloads (60–0.94μg) of O1 Manisa. They were challenged by intradermolingual inoculation with live FMDV, either O1 Manisa or O1 Campos. Unvaccinated naïve control cattle (n =20) were also challenged with either the O1 Manisa or O1 Campos viruses and all developed generalized FMD. The protection results for the vaccinated cattle revealed that higher payloads of O1 Manisa vaccine were needed to protect against heterologous challenge compared to that for homologous challenge. The 50% protective dose (PD50) values for the vaccine in experiments 1 and 2 were found to be 28.78 and 9.44 for the homologous challenge and 3.98 and 5.01 for heterologous challenge. Furthermore, protection against O1 Campos required a higher level of vaccine-induced antibody against this virus compared to the level of O1 Manisa neutralizing antibody associated with protection against homologous challenge. The 50% protective level of in vitro neutralizing antibody was found to be log10 1.827 for O1 Campos and log10 0.954 for O1 Manisa based on O1 Manisa based virus neutralization test. [Copyright &y& Elsevier]

Use of recombinant Bm95 isolated from an Argentinean strain of Rhiphicephalus microplus A as a vaccine candidate to control the tick infestation in India was investigated. Recombinant Bm95 expressed in yeast, Pichia pastoris. Purified protein blended into a vaccine using aluminium hydroxide as an adjuvant. An adverse effect on the reproduction of ticks was observed in vaccinated animals indicating reduced the environmental contamination and source of infestation indicating its use of Bm95 in the immunological control of ticks in India. [ABSTRACT FROM AUTHOR]