**4. Vaccination**

Vaccination is an important component for the constructive management of cattle diseases. In-order to ensure effective vaccination of animals, knowledge about the pathogen, its disease-causing ability, host factors, immune status, stress and optimal vaccination timings should be taken into considerations [58].

For the management of respiratory diseases in cattle, modified live-virus vaccines are generally recommended. The live vaccines were available commercially since 1970s. Vaccination is considered to be effective considering it should be biologically active and stimulate active immunity against the pathogenic agent present in the vaccine. It should reduce the clinical illness, improve animal weight and should be economical with long-lasting immunity in commercial setting. However, the existing data suggests that the vaccine immunity gets compromised because during the transportation of animals, the release of pro-inflammatory factors put the animal under stress. Therefore, it would be beneficial to administer vaccine before animal shipment [58].

Excellent animal based surveillance studies along with vaccination might play a crucial role in the management of *Brucella* infection. In case of *B. meletensis*, the two commonly used vaccines are Rev1 and RB51. These vaccines do not interfere with the result of serodiagnosis and therefore can be used in the susceptible animal population for controlling *Brucella*-induced infection and relative abortions [47].

In veterinary virology, both live and killed vaccines are used for controlling livestock diseases, however their efficacy have been compromised due to new and re-emerging virus infections. Therefore, it is necessary to develop new vaccines containing prevailing serotypes and subtypes. Nano-particles have gained considerable fame in veterinary science due to their small size, large surface area and their ability to act as carrier vehicle for antigen delivery and immunogenicity [13]. In case of FMD infection, inactivated vaccines are used mostly but in order to initiate a protective immune response, a time period of almost 7 days is required. Therefore, in order to avoid such situation, silver nanoparticles were used as an adjuvant for the polyvalent inactivated FMD vaccines. Silver nano-particles have been shown to induce a much stronger humoral and mucosal immunity by enhancing interleukin production. Therefore, for long-lasting immunity, silver nanoparticles can be used as adjuvant in vaccine subunits [59]. Further, understanding the molecular mechanism of pathogen and their interaction with host and environment might also be beneficial for future vaccination studies.

### **5. Conclusion**

Management is key to disease prevention and is utmost necessary for global and national food security and animal wellbeing. Dairy cattle and buffaloes play important role in economic development because of their milk and meat production ability. However, livestock and dairy animals are vulnerable to variety of metabolic and infectious diseases, the introduction of new animal in the herd increases the likelihood of disease. Besides this, antimicrobial resistant strains are also circulating in the environment. The dissemination of antibiotics resistant genes in animals from the surrounding environment poses threat to animal in the form of abortion and reproductive disorder. Procedures to reduce the risk seem plausible. Many live and inactivated vaccines are administered to animals to protect them from diseases. However, these vaccines may not provide lifelong immunity Therefore, a comprehensive surveillance system and mass vaccination programs are needed in light of current dilemma to cope with the scenario.
