A successful breeding starts months before the animals ever meet. The dam carries the pregnancy, whelps the litter, and does the hard biological work — her preparation determines almost everything about how it goes. Here's the timeline experienced breeders follow.
3–6 months out: full veterinary exam, updated vaccinations, parasite screening, and brucellosis testing for dogs. Review her health clearances and confirm they're current — eye exams and cardiac evaluations expire, and you don't want to discover a lapsed clearance two weeks before the breeding. This is also the time to finalize your breeding partner, review the contract, and calculate the expected coefficient of inbreeding for the pairing.
1–2 months out: optimize body condition. She should be lean but not thin — you should feel ribs easily without seeing them, with a visible waist from above. Overweight females have smaller litters and more whelping complications; underweight females may not conceive at all. Transition to a high-quality, highly digestible diet now, not after conception. Many reproduction veterinarians recommend beginning folic acid supplementation before conception to reduce the risk of cleft palates — ask yours.
When her cycle begins: track from day one of visible discharge or vulvar swelling, and mark it on a calendar. Progesterone testing for dogs typically starts around day 5–7 and pinpoints ovulation far more accurately than counting days alone — ovulation timing varies enormously between individuals, and mistimed breedings are the most common cause of 'infertility' that isn't. Plan for testing every 2–3 days once you start, and share results with the stud owner immediately so travel can be timed correctly. For cats, who are induced ovulators, the logistics differ — but tracking cycles is just as important.
Breeding itself should be calm, supervised, and brief. Introduce the animals in neutral territory if possible, allow natural courtship, and never leave them unattended. For dogs, expect a tie lasting 5–30 minutes — this is normal and should never be forced apart. Plan for two breedings 24–48 hours apart when possible, which meaningfully improves conception rates.
Afterwards, confirm pregnancy by ultrasound around day 28–30 — earlier than that is unreliable. If confirmed, transition to a growth or all-life-stages formula diet around week five, increasing calories gradually through the final trimester. Set up the whelping area by week six so she can claim it as her own, and have your vet's emergency number and a plan for after-hours care ready well before day 63.
The PetsRulez.com guidelines page has more resources for every stage, and our messaging feature makes coordinating timing with your match simple — share progesterone results, arrange travel, and keep a written record of everything agreed.