If you’re worried about getting doggy sperm on your trousers when your fixed dog humps your leg, the answer is yes, you can.
Dogs who have been neutered or spayed (commonly referred to as “fixed”) can still ejaculate, but the composition of their ejaculate will be different from that of intact dogs.
Why dogs can ejaculate even when they’re fixed
Neutering involves the removal of your male dog’s testicles (or the ovaries and uterus in the case of spaying a female dog). This takes away the primary source of sperm production, and also the hormones responsible for making your male dog want to hump and pee on everything.
After neutering, while dogs can still produce some residual sperm, it’s typically in much smaller quantities than in intact males.
Ejaculation, if it occurs, would primarily involve the secretion of a small amount of fluid from the prostate gland and seminal vesicles (little sperm ingredient factories). This fluid is mostly devoid of sperm and won’t serve up the same reproductive magic of intact dogs.
So, while neutered dogs may still show some sexual desires (like humping your leg or female dogs in the park), and can still ejaculate, it’s not usually associated with reproduction.
The ejaculate produced by a fixed dog does not contain the same reproductive capacity as that of intact males.