BACKGROUND: Bovine Herpes Virus-1 (BHV-1) belongs to the  Alpha herpesviral family. The virus is the cause of Infectious Bovine Rhinotracheitis (IBR) and Bovine Abortion. In the initial infection, the virus proliferates excessively. Moreover, shedding the virus leads to conditions in the latent phase of the disease. Infectious Bovine Vulvovaginit (IPV ) is the genital form of the disease that represents a genital infection and transmits via pustules and mucopurulent secretions. Exposure to the virus in genital mucosa leads to IPV infection through mating or artificial insemination and the diseases that can be transmitted to healthy livestock by frozen sperm during artificial insemination.OBJECTIVES: Viral contamination of the semen is one of the routes to spread the disease among dairy cattle. Therefore, we investigated the presence of the virus in domestic and frozen imported semen consumed in industrial dairy cattle farms.METHODS: In the present study, 140 frozen straws were collected. After melting each straw, 200 µl of obtained semen was used for DNA extraction, which was done directly on the semen samples and via a Genome Extraction Kit. Subsequently, to ensure the accuracy of the extraction, the PCR technique was done using PRM-1 gene primer. Tracking the viral genome was done using the PCR technique and known primers.RESULTS: In total, one out of 140 samples was found to be virally contaminated, and IBR contamination was confirmed by repeating all the steps and determining the gene sequence.CONCLUSIONS: It is necessary to further investigate the possibility that contamination can be transmitted via frozen semen, given that even one out of 140 samples is contaminated, and the importance of the disease.

Objective: The Newcastle disease virus (NDV) is an infectious disease that causes very high eco¬nomic losses due to decreased livestock production and poultry deaths. The vaccine's ineffec¬tiveness due to mutation of the genetic structure of the virus impacts obstacles in controlling the disease, especially in some endemic areas. This study aimed to provide an alternative treatment for NDV infection by observing the viral replication inhibitor activity of Clostridium perfringens sialidase in primary chicken embryo fibroblast (CEF) cells. Materials and Methods: The virus was adapted in CEF monolayer cells, then collected thrice using the freeze–thaw method and stored at −20&#xb0;C for the next step in the challenge procedure. C. perfringens crude sialidase was obtained, but it was further purified via stepwise elution in ion exchange using Q Sepharose® Fast Flow and affinity chromatography with oxamic acid agarose. The purified sialidase was tested for its toxicity, ability to breakdown sialic acid, stopping viral replication, and how treated cells expressed their genes. Results: According to this study, purified C. perfringens sialidase at dosages of 187.5, 93.75, and 46.87 mU effectively hydrolyzes CEF cells' sialic acid and significantly inhibits viral replication on the treated cells. However, sialidase dosages of 375 and 750 mU affected the viability of mono¬layer CEF cells. Interestingly, downregulation of toll-like receptor (TLR)3 and TLR7 (p < 0.05) in the sialidase-treated group indicates viral endocytosis failure. Conclusions: By stopping endocytosis and viral replication in host cells, sialidase from C. perfrin¬gens can be used as an alternative preventive treatment for NDV infection. [J Adv Vet Anim Res 2022; 9(2.000): 335-345]