Call us now
.png)
Quick answer: have your cow or buffalo checked for pregnancy by a veterinarian about 30 days after AI. An ultrasound scan can confirm pregnancy, or show that she is open (not pregnant), from about day 28–32. A rectal examination by an experienced vet is reliable from about 35–45 days. Watching for a return to heat 18–24 days after AI is a useful first sign, but it is not proof. Because some early pregnancies are lost, ask for a second check around day 60 or later, and again before drying off. Do not wait for the belly to show. Each missed month adds about 21 days to the calving interval.
| Days after AI | What to do | What it tells you |
|---|---|---|
| Day 0 | Write down the AI date, bull/semen code and who did the AI | Every later step depends on this date |
| Day 18–24 | Watch closely for heat signs morning and evening | If she comes back into heat, she is very likely open. Call the AI technician for re-insemination. No heat is not proof of pregnancy |
| Day 28–35 | Ultrasound scan by a vet (cows and buffaloes) | Earliest reliable answer on the farm. It can also see the heartbeat (a live embryo) and twins |
| Day 35–45 onwards | Rectal examination (per-rectal, PD) by an experienced vet | Reliable and low cost. Earlier checks need more skill and should only be done by a vet |
| Day 60–90 | Re-confirm pregnancy | Catches early pregnancy loss so the animal can be re-bred quickly |
| Before drying off | Final check | Avoids drying off an open animal and losing a lactation |
A cow or buffalo that is open but not detected loses one heat cycle (about 21 days) every time it is missed. Many farmers find out only at 3–4 months, when the animal comes back into heat or the belly does not grow. By then, one or more chances to conceive are gone. This is one of the main reasons for long calving intervals in India. Our guides on one calf a year and the buffalo calving interval show what each lost month costs. An early check finds the open animals while there is still time to act.
A cow's heat cycle is about 21 days. If she shows heat again 18–24 days after AI, she almost certainly did not conceive. But a cow that shows no heat is not always pregnant. She may have silent heat (common in buffaloes, especially in summer), an ovarian cyst or anestrus. That is why non-return is only a first screen.
A vet passes an ultrasound probe into the rectum and sees the uterus on a screen. The MSD Veterinary Manual notes that ultrasound can identify open cows from about 28–32 days after breeding. It can also confirm the embryo is alive (heartbeat), detect twins and estimate the age of the pregnancy. In buffaloes, a study of 275 animals found ultrasound picked up 100% of pregnancies from day 31 after mating, but fewer than half (44%) when scanned at days 19–24. Ultrasound is the best choice when you want an early answer, and many private vets, dairy co-operatives and state veterinary hospitals now offer it.
This is the traditional "PD" check. The uterus lies just under the rectum, so a trained vet can feel it through the rectal wall. That is why the check is done "through the anus". University of Florida extension guidance notes that experienced examiners can detect pregnancy from about 30–40 days. Checks before about 45 days should only be done by a veterinarian, because rough handling at that stage can harm the pregnancy. Done correctly, it is quick, cheap and reliable. A pus-filled uterus (pyometra) can feel similar to an early pregnancy, which is one more reason to use an experienced vet.
These laboratory tests measure pregnancy-associated glycoproteins (PAGs) released by the placenta. In a US study of Holstein cows, tests at day 32 were 92% accurate on blood plasma and 89% on milk compared with ultrasound. They are useful where a scanning vet is not available. Their availability in India depends on your area, so ask your vet or milk union.
ICAR-Central Institute for Research on Buffaloes, Hisar, developed an early pregnancy diagnosis kit called Preg-D. It tests urine, needs no cold chain, and samples can be processed up to 24 hours at room temperature. In January 2024 ICAR announced that production and marketing rights had been licensed to a company. Ask your vet or local dairy union whether it is available near you. Confirm a positive result with your vet, especially before deciding not to re-breed.
| Method | Earliest useful day | Who does it | Good points | Limits |
|---|---|---|---|---|
| Watching for heat | 18–24 | Farmer | Free, finds many open animals early | Silent heat and anestrus look like "pregnant" |
| Ultrasound | 28–32 | Veterinarian | Earliest firm answer, sees heartbeat and twins | Needs a vet with a scanner |
| Rectal examination | 35–45 | Veterinarian | Cheap, widely available | Needs skill. Early checks only by a vet |
| Blood / milk PAG test | 28–32 | Sample sent to a lab | No rectal handling | Lab access. Re-test later to catch losses |
| Urine kit (Preg-D) | Ask your vet | Vet or trained worker | Simple, no cold chain | Check local availability. Confirm with a vet |
Not every early pregnancy survives. In the same US study, about 13% of cows found pregnant at day 32 had lost the pregnancy by day 102, and the authors advised re-testing cows at 74 days or later. If you assume an animal is pregnant after one early check and she quietly loses the pregnancy, you can lose several months before you notice. A re-check around day 60–90 finds these animals so they can be examined and re-bred.
For the full list of breeding-support options, see our guide to the best uterine tonic for cows and buffaloes and which Cattle Remedies product for which problem.
With ultrasound, from about day 28–32. With a rectal examination by an experienced vet, from about day 35–45. Watching for a return to heat at 18–24 days is a useful early sign but not a confirmation.
The same timing works for buffaloes. In one study of 275 buffaloes, ultrasound detected every pregnancy from day 31 after mating. Because buffaloes often show silent heat, a vet check is even more important than watching for heat.
AI के 18–24 दिन बाद गाय फिर से गर्मी (हीट) में आए तो वह शायद गाभिन नहीं है। पक्की जाँच के लिए AI के लगभग 30 दिन बाद पशु चिकित्सक से अल्ट्रासाउंड या 35–45 दिन बाद गुदा जाँच (PD) कराएँ, और 60–90 दिन पर दोबारा पुष्टि कराएँ।
Yes, when it is done gently by an experienced veterinarian. Very early checks need more skill, which is why checks before about 45 days should be done only by a vet. Ultrasound needs less handling of the uterus.
Some pregnancies confirmed early are lost later. In one study, about 13% were lost between day 32 and day 102. A second check finds these animals quickly so they can be treated and re-bred.
More in this series: buffalo calving interval: how to reduce it; one calf a year; silent heat in cattle; age at first calving in heifers; pregnant cow and buffalo care.
Reviewed for accuracy against the sources above on 29 October 2026. This article is general educational information for dairy farmers and is not a substitute for veterinary advice. Pregnancy diagnosis, reproductive examination and any hormone treatment must be done by a qualified veterinarian. Cattle Remedies products are supportive care and work best alongside good feeding, heat detection and veterinary management.
By Cattle Remedies
