To ultrasound, or not to ultrasound, now that is a great question! Using ultrasound for the diagnosis of pregnancy has been around for a while now. You probably all know by now the advantages of ultrasound, but let’s just recap so those of you who are using it remember why and for those of you who are not using it remember why not.
First some disadvantages. Ultrasound can be used to diagnose pregnancy around a week earlier than digital palpation but requires more equipment.
1. Expense - The ultrasound machine and probe are expensive and so there is usually a fee associated with the use of the ultrasound for reproductive work.
2. Perceived Increase in Fetal Loss - This can be a little confusing, but hopefully I can explain. This is not really a disadvantage, just a reality that needs to be accounted for. If ultrasound is used to diagnose pregnancy earlier than manual palpation was, more pregnancy losses due to miscarriage and embryonic death will be recorded. The actual number of these incidences will not go up, but the number you know about will increase because pregnancy is being diagnosed earlier.
Now some advantages. The ultrasound gives a full thickness image of the uterine horn and ovary. This allows us to visualize the fluid of the pregnancy, the developing fetus itself, and the whole cross section of the ovary, not just the surface.
1. Early Diagnosis – Ultrasound can pick up on fluid in the uterus far better than the fingers can. Using fluid and a CL on the same side, we can diagnose positive signs of pregnancy down to around 24 days. For a definitive diagnosis of pregnancy, the developing embryo needs to be observed which can consistently begin to be seen around 28-29 days. The best diagnosis of pregnancy begins at around 30 days when a heartbeat can be observed.
2. Fetal viability – Viability and health of the calf can be determined by presence of a heartbeat on ultrasound. The fluid around the embryo/fetus can also be seen and evaluated for cloudiness which can be a sign of impending fetal/embryonic loss.
3. Sexing – ultrasound allows the added benefit of being able to sex calves after 60 days. After 85-90 days, the calf is often too deep in the cow to get a good view for sexing. For best results, sexing should be done in that 60 to 85-90 day window.
Ultrasound is another tool that can be used in your reproductive program to add value by increasing the information you get from pregnancy check. If you have any more questions, just ask!