
Hi,
Although I haven't had a need to use it myself, in your position:
- IF it's a bitch worthy of mating
- IF it's an appropriate mating
- IF it can be arranged for her to have a settled whelping with the appropriate care (as she may whelp before you get back from your holiday)
- IF it would be a major problem for you not to be able to breed from this bitch later
.......... then I'd let it run it's course.
As I say, not personal experience, but many people who've used the injection do seem to report problems with subsequent seasons and pyometra - OK, it may be urban myth, but that's no help if you do it and then find out it's true - I don't think I'd take the chance.
M.