In the presented study, we developed a nanogold lateral glow immunoassay-based technique (LFI-COVID-19 antigen test) for the detection of SARS-CoV-2 nucleocapsid proteins; the developed LFI-COVID-19 Ag test has been tested for limit of detection (LOD), cross-reactivity and interfering substances, and performance. It was found that the performance of the developed LFI-COVID-19 antigen test when it was evaluated by RT-qPCR indicated 95, 98, and 97% for sensitivity, specificity and accuracy, respectively. This complies with the WHO guidelines. It was concluded that the developed LFI-COVID-19 antigen test is a point of care and an alternative approach to current laboratory methods, especially RT-qPCR. It provides an easy, rapid (within 20 min), and on-site diagnostic tool for COVID-19 infection, and it is a cheap test if it is manufactured on a large scale for commercial use.

In this research Romanian Sheep pox virus was identified and confirmed by using PCR, Live attenuated Romanian Sheep pox vaccine (RSPV) was prepared and its titer on VERO cell was log 10 2.5 TCID50/dose. It was sterile, safe and potent. We used eight susceptible calves 6-8 months old, five calves vaccinated with 0.5 ml of prepared RSP vaccine intra dermally (I/D) in tail folds while three calves kept as control. Evaluation of both acquired humoral and cellular immunity by using lymphocyte proliferation assay, SNT, ELISA and Interferon Gamma Bioassay (IFN-ᵧ). The result showed that lymphocyte proliferation began to increase till reach to its peak (1.629) at 10 th day then decrease after that, While Interferon gamma (IFN-ᵧ) detected in 1 st day till 7 th day post vaccination then decreases after that. Results of SNT and ELISA revealed that Protective serum neutralizing antibody titer started at three weeks (1.5), (1.09) post vaccination then reach to its peak at 12 th weeks (2.5), (1.85) respectively and persisted till 28 weeks. From this study we found that live attenuated RSP vaccine a good immunogenic response where it was induced a high level of antibody titer with prolonged duration of immunity and higher lymphocyte and interferon gamma levels, So It considered good vaccine to control Lumpy Skin Disease (LSD).

Rift Valley fever (RVF) is a viral zoonosis that primarily affects animals but also has the capacity to infect humans. The disease also results in significant economic losses due to death and abortion among RVF-infected livestock. A lateral flow device (LFD) was developed for the rapid detection of IgG and IgM anti-RVF antibodies in infected and vaccinated ovine sera. The conjugated RVF antigen with nano-gold was used as a detector antigen and was laid on a conjugated pad. The staphylococcal protein A was used as the capture complex (antibodies IgG-antigen conjugated with nanogold) at the first test line of device and anti-IgM antibodies were used as the capture complex (antibodies IgM-antigen conjugated with nanogold) at the second test line of device. When compared with RVF specific ELISA, The sensitivity, specificity, and accuracy of developed LFD for detection of IgG were found to be 88.2, 96.9 and 94.0%, respectively, while the same for detection of IgM was found to be 100, 96, and 96%, respectively.

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