You can determine if a sow is pregnant through various methods, with veterinary diagnosis being accurate approximately 30 days after breeding, while visual signs may appear later.
Here's a breakdown of how to tell if a sow is pregnant:
1. Veterinary Diagnosis:
- Ultrasound: A veterinarian can perform an ultrasound examination approximately 30 days after breeding to detect pregnancy. This is a reliable and early method.
- Blood Test: Blood tests can also be used to detect pregnancy by measuring specific hormone levels. Your vet can advise on the timing and accuracy of this method.
2. Observation of Physical and Behavioral Changes:
- Failure to Return to Estrus (Heat): A primary indicator is the absence of the sow returning to heat approximately 18-24 days after breeding. If the sow doesn't show signs of estrus, it's a positive sign.
- Abdominal Distention: A slight abdominal distention might be noticeable by perceptive owners around 80-90 days of gestation.
- Mammary Development: Mammary gland development will occur later in the gestation period. The teats will become more prominent.
- Behavioral Changes: Sows may exhibit calmer behavior, increased appetite, and a tendency to nest-build as they approach their farrowing date (around 114 days gestation). These are not definitive signs but can be suggestive.
3. Summary Table of Methods and Timing
| Method | Timing | Accuracy |
|---|---|---|
| Ultrasound | ~30 days after breeding | High |
| Blood Test | Consult veterinarian for optimal timing | High |
| Absence of Estrus | 18-24 days after breeding | Moderately reliable early indicator |
| Abdominal Distention | ~80-90 days of gestation | Can be difficult to discern early on |
| Mammary Development | Later stages of gestation | More noticeable as farrowing approaches |
Important Considerations:
- False negatives are possible, especially with visual observation.
- Stress or illness can disrupt the estrus cycle, so absence of heat is not always a definitive sign of pregnancy.
- Consulting a veterinarian is crucial for accurate diagnosis and management of the pregnant sow.
