I was told this vaccination protocol for goat kids very recently by a good vet and it makes sense to me:
1. If the Mum was vaccinated within 3 months and the kid is feeding from mum, then start the kid on Lambivac at 3 months as the they should have passive immunity from their mums up till then.
2. If not feeding off mum, or mum not vaccinated, then give lambivac at 2 weeks old for the clostridial diseases. Then 1 week later give Ovipast Plus for pasteurellosis caused by M. haemolytica and P. trehalosi. Obviously Lambivac booster 4- 6 weeks after the first injection and the Ovipast give a booster 4 - 6 weeks after the first injection. Then booster for Lambivac every 6 months. It was suggested to me that the Ovipast is only needed when they are young and also useful to give to a female who is breeding, as again she will pass the passive immunity on to the kid to ensure immunity in the first few weeks/ months.
I would always vaccinate as a viable healthy precaution.