A lot of diseases affect animals which need treatment. Antibiotics and other
drugs have been widely used in the treatment. Drug residues in milk and meat are the
main issues and pose health risks to humans. A vaccine is the only solution to keep
animal products safer from drug residues. Modern veterinary vaccine history started in
the 19th century when Edward Jenner used antigens from cowpox pustules. A vaccine
is a weakened organism or part of an organism that is given to animals to produce
immunity by the body. Soon after the development of vaccines, safety issue arises.
Especially live attenuated vaccine was a matter of concern as it may revert to cause
disease. Nowadays, most of the livestock vaccines are live attenuated or killed.
Vaccines have been developing against bacteria, viruses and parasites also. Animal-origin products are also contaminated with parasite infection and are a source of
infection to other animals and humans. Parasites usually stay in the gastrointestinal
tract of animals, and oocytes are disseminated through feces into the environment,
which are transmitted to other animals. Vaccines are cost-effective methods to prevent
diseases in animals and humans. It not only enhances animal meat and milk production
but also saves humans from zoonotic diseases. Without vaccines against major animal diseases, it will not be possible to feed 7 billion people with proteins. Zoonotic
diseases, such as brucellosis and Leptospirosis, will be more prevalent in the world
without the vaccination of animals. Rinderpest is almost eradicated from the globe and
will be the second disease after smallpox which is diminished through proper
vaccination and surveillance.
Keywords: Immunity, Recombinant vaccine, Subunit vaccine.
