The first vaccination

Only when MDA falls to a moderate to low level, will the puppy or kitten respond to vaccination and produce its own ("active") antibody levels. Vaccination at this point simply takes over the mother's role in providing protection.

In general, the earliest age for vaccination of puppies is between 6 and 12 weeks.

However, as most puppies do not leave the breeder until they are 8 - 9 weeks old, this in practice is the age at which the majority of puppies receive their first vaccination. For kittens, vaccination may start from 9 weeks of age. It is important to note that the primary course always consists of two or more vaccinations. This is because:-

timing for effective vaccination varies from puppy to puppy and kitten to kitten (because of unknown MDA levels). some vaccines such as Leptospirosis need to be administered twice in order to achieve a high enough level of immunity.

Based upon local experience, your own veterinary surgeon will advise the best schedule to adopt, but the aim will always be to provide your pet with the best possible protection.