When do you give your bitch the CHV?  Just prior to mating or after?

is that the herpes injection? i think it can be 7 days before or 7 days afet, contact your vet, they should be able to help,    

sami,

is the vaccine still in short supply?

Don't think so - I've managed to get it from my vet within 2 days.

my understanding is that it can be given  from  day one of season   to 7-10 days  after mating.  Repeated  6 weeks later i.e.  1-2  weeks before expected date of whelping.