Dogs' mating may be natural and artificial, which is more and more popular. Bull Terriers' mating is often processed with enforcement upon female and it's justified till certain point. Many females are more dominant than a male so mating is possible with enforcement only. Some of them are quite aggressive so artificial impregnation is recommendable. Bitches are capable to mate during their first driving, but it's not recommended, kynological rules don't allow mating at that age also. Optimal age for first litter is about 18 months, apropos with completion of physical and mental development.
Before mating bitch's owner must define exact term that is optimal for mating. The easiest and quite reliable way in estrus determination is bringing of "tester" male. Since the day when female accepts male for the first time (stands still under the male with her tale set astray) must elapse another 2-4 days before mating. I accentuate that female shall not bleed, and if she's bleeding wait a little bit longer or ask veterinarian for advice. Optimally date for mating could be determined by examination of vaginal excretion. For natural mating male's courtship is important. Stimulated by female's scent, by sniffing and licking of vulval area, he's preparing for a jump. Female stands still, trying to find the best position. Then male jumps female with partially erected penis, penetrates into female. After several penetrating movements full erection is achieved, which results copulation which may last to 30 minutes. Even if copulation is not achieved it is possible to succeed in female's impregnation but it's advisable to keep female with her hind part up for 15 minutes (this could also be done while copulation is in process). At the end female should be taken for a walk while not letting her urinate for some time.
| Male ejaculates sperm in three phases. First fraction of ejaculation is unessential for impregnation and it occurs after several penetrating movements. Second fraction is ejaculating when male stops penetrating movements and it's plentiful of spermatozoas therefore it's of the most significance. Then follows third fraction, which is not rich in sprematozoas but it has great volume so it is important for pushing second fraction to ovary's egg. During the third phase male comes down of female posturing characteristic position - heads reversed one from another while their hind parts are combined. |  |
Mating should be processed, in environment that is known to male, in peace, with familiar persons in fewest possible number (don't make a circus of it). It is significant to provide surface that is not slippery. Mating is possible in environment that is strange to male, but before mating male should enquire that particular environment. If male rejects mating immediately after two dogs have met, often reasons are psychic brake of sexual reflexes, which occurs due to pain, fear, strange people or strange dogs presence, bad, rough treatment of a dog. It's important to be decent with dog (it is better for you to authorize other person to take over leading of the dog until mating is processed than to be nervous, to transmit anxiety on dog and on other people). Beside this aspect of male's disability to impregnate female there are also:
- inborn impotency - different inborn anomalies of male's sexual organs;
- physical impotency - caused by injuries and infections on sexual organs or by injuries and infections of other parts of the body due to which jump and mating are impossible (injuries of legs, paws, chest);
- hormonal impotency - due to hormonal disturbance;
- nutritive impotency - occurs due to fault nutrition;
- sexual exhaustion - occurs due to frequent mating;
- senile impotency - it can happen to old dogs.
Reason of unsuccessful mating also could be female sterility (curable or permanent), impregnation outside of estrus, or impossibility of impregnation due to sperm transformation (spermatozoas' wrong build, weakly movable or dead spermatozoas, faults in chromosomes...).