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This study critically reviews the literature on the prevalence and genotypic distribution of Bovine Leukemia Virus (BLV) in Asia, specifically targeting enzootic bovine leukosis, a chronic disease affecting cattle’s life and milk production along with reduced fat yield, that causing economic losses due to increased susceptibility to pathogens. European countries are eradicating BLV but Asia has a high prevalence, particularly in Asian cattle. Enzootic bovine leukosis (EBL) has distinct clinical stages: asymptomatic, persistent lymphocytosis, and lymphosarcoma. It typically occurs in adult animals, with 60% being asymptomatic during the aleukemic stage, 30% developing persistent lymphocytosis, and 5% developing lymphoma. Databases like PubMed and Google Scholar were used to search molecular and prevalence studies from 2000-2024, focusing on Asian countries. Prevalence of bovine leukosis (BL) in Asia varies significantly, with high rates in central and eastern regions. BLV is a global disease, has increased in Asia with highest prevalence in central Asia about 40.0–84.0% (Kazakhstan), 35% in Eastern Asia (Japan), and 58.3% in Southeast Asia (Thailand). BLV genotypes G1, G4, G6, G7, G12, G3, G4, G6, G7, and G10 are prevalent in various regions of Asia, with G1 being most prevalent globally. These genotypes might be spread due to animal trading, and animal domestication, affecting various countries. This review provides the current status of enzootic bovine leukosis in Asia, emphasising the need for a closed trading system to control the disease.

Necrotic enteritis is an important disease of poultry that causes economic loss to the broiler industry. Clostridium perfringens is an important bacterium that is responsible for causing necrotic enteritis. Antibiotics are mainly used to control C. perfringens but due to resistance antibiotics are banned in many countries like Canada, Hong Kong, and the European Union. Many alternatives such as probiotics, essential oils, and postbiotics have been developed to control C. perfringens. Among them, probiotics are very important because they can increase beneficial bacteria in the intestine, create a competitive environment in the gut region, and prevent the adhesion and colonization of pathogenic bacteria such as C. perfringens. Probiotics cause immune system modulation, reducing inflammatory markers such as cytokines. Lactobacillus based probiotics also cause weight gain, improve feed conversion ratio, and decrease mortality in poultry which in turn increase profit margin. Several studies have reported that when poultry populations were challenged with C. perfringens then these probiotics prevented intestinal lesions, provided anti-inflammatory effects to the intestine, prevented damage to the villi, and did not allow C. perfringens to form its colony in the intestine. The main aim of this review paper is to explain the updated information on necrotic enteritis, the damages caused to the gut, and the mechanism of actions through which Lactobacilli work against C. perfringens.

The growing global population has amplified the demand for food, making the international trade of livestock a significant threat to animal and public health due to the increased risk of zoonotic disease transmission through animal movement or the consumption of their products. Biosecurity measures (BSMs) and vaccination are two essential tools that, when effectively implemented, can significantly reduce the spread of diseases from livestock. However, their failure not only escalates the burden of disease but also compromises food security and public health. Weak or poorly enforced BSMs can undermine the efficacy of vaccinations, creating challenges against disease prevention efforts. Conversely, robust BSMs such as nutritional and environmental management, routine monitoring of disease, farm management, and hygiene provide a critical foundation for successful vaccination programs by minimizing disease exposure and ensuring vaccine effectiveness. Inappropriate vaccination administration, inadequate cold chain management, and the frequency of immunosuppressive illnesses are also reported as contributing factors to vaccine failure. This review delves into the interconnected roles of BSMs and vaccination, unveiling the importance of the implementation of biosecurity principles in preventing vaccine failure. It also explores how the integration of biosecurity practices and vaccination strengthens animal health systems, mitigates zoonotic risks, and enhances overall food safety. Future research should concentrate on integrated biosecurity techniques by strengthening on-farm biosecurity protocols, proper handling and administration of vaccines, careful disease surveillance, and awareness programs thereby increasing the resilience of our livestock industry against notable diseases.