For want of a better word, how would you define a slip mating? Would the dog have had to tie albeit outside the bitch for it to be a slip mating that could result in pregnancy, or could he have started to ejaculate before any tie has occurred?

Its when the dog ejaculates inside the bitch but no tie occurs

Same response as lel

So can a male dog ejaculate WITHOUT the glands that causes a tie being swollen?

The dog will be swollen to ejaculate anyway, just that there is no tie inside the bitch. When he comes out of the bitch he can stay enlarged for a bit. Some say it is the bitch that causes the tie to occur

Thanks -this is what I was thinking.

Yes, it is deffinatly the bitch that 'creates' the tie.

Well no the glans penis swelling inside the bitch and her contracting her muscles do.