The use of ultrasound in the dairy industry is a crucial tool for detecting early pregnancies, identifying open cows and fetal sexing. Click to learn more about ultrasound use on dairies.
ReproScan ultrasound equipment provides solutions for all the challenges of dairy cattle reproductive ultrasound. When selecting ultrasound equipment for dairy cattle reproductive examinations, one needs to consider many factors.
A presumptive diagnosis of pregnancy can be made as early as 26 days. This diagnosis is based on the presence of clear uterine fluid and a functional Corpus Luteum greater than 20 mm on the same side as the fluid. These pregnancies must be rechecked as the rate of pregnancy loss at this stage can be quite high. Very early pregnancy testing is usually done with a handheld 6.5 MHz linear rectal probe such as BoviScan HD, BoviScan Linear or ReproScan Flexx (6.5 MHz probe). Pregnancy testing 30 days and up gets considerably easier to perform. The heartbeat in the embryo can be used confirm the viability of the pregnancy. The 4.0 MHz convex rectal probe can be used for early pregnancy exams with the “arm in cow” method. The larger field of view makes some examinations easier but there is a slightly lower resolution with the larger scanning area. Extension arm ultrasound usually starts at 35 days and up in moderate sized seasonally bred dairy cattle.
Ovarian examinations are usually done with a 6.5 to 7.5 MHz linear rectal probe such as the BoviScan HD, BoviScan Linear or ReproScan Flexx (6.5 MHz probe). The presence or absence of a functional Corpus Luteum is often used to determine which estrus synchronization program will best suit an individual cow. Some veterinarians prefer a C20 micro convex probe on their BoviScan or ReproScan Flexx unit. Please contact your ReproScan representative to discuss which ReproScan or BoviScan unit is right for your dairy practice.
Fetal aging in early pregnancies is done by measuring the fetus with the 1 cm grid or 2 cm grid. Fetal aging charts are available. Crown rump length and head diameter are the most commonly used measurements.
Fetal aging dairy cattle in advanced stages of pregnancy is more difficult and less accurate than earlier in gestation. The 4.0 MHz convex rectal probe with its larger field of view is better for later term examinations and dry off checks.
Fetal sexing is usually done by “arm in cow” method from 58 to 80 days with a 6.5 MHz linear rectal probe such as on the BoviScan HD, BoviScan Linear or ReproScan Flexx. Fetal sexing can be done with the 4.0 MHz convex rectal probe with or without the extension arm. Depending on the size of dairy cattle, sexing fetuses from 70 to 90 days often works out better when using the 4.0 MHz convex rectal probe.
Seasonal dairy cows are often smaller framed and easier to pregnancy test. The 4.0 MHz ReproScan XTC and the BoviScan Curve do an excellent job of pregnancy testing seasonal dairy cattle. This type of pregnancy testing is similar to cow-calf pregnancy testing. The ReproArm extension arm is used to increase speed and reduce fatigue and injuries to the veterinarian. Fetuses are often aged in 5 day increments from 35 to 100 days.
Seasonal dairying is a large industry in New Zealand and extension arm ultrasound is used by 100% of veterinarians and technicians that provide pregnancy testing services to these dairies.