Early and precise pregnancy diagnosis is critical for efficient livestock reproduction. Identifying open (non-pregnant) animals – the “problem animals” – allows farmers to make timely management decisions and improve herd fertility. Traditionally, producers have relied on methods like estrus observation, rectal palpation and hormone tests. In cattle and other large livestock, rectal palpation and ultrasonography have been the most common direct pregnancy tests. Estrus observation (watching for return to heat at ~21–24 days post-breeding) is simple but often unreliable. Blood or milk assays for progesterone or pregnancy-associated glycoproteins (PAGs) can confirm pregnancy around 28–30 days, but require lab processing. By contrast, ultrasound imaging (which the user’s guidelines call “ultrasound” instead of “B-mode”) offers real-time visualization of the conceptus and thus has reshaped pregnancy detection on farms.

Traditional Pregnancy Detection Methods

Common on-farm methods include:

• Estrus Observation: Detecting return to heat (~18–24 days after insemination) suggests non-pregnancy. This method requires no equipment, but miss silent heats and can falsely indicate pregnancy when animals have other cycle issues.

• Rectal Palpation: A trained technician palpates the uterus per rectum (or abdomen in pigs) for fluid, membranes or the fetus. In cattle, this is reliable only after about 35–45 days of gestation. Palpation is inexpensive and immediate, but it requires skill (and can risk embryonic loss if done too early.

• Hormone/Protein Tests (Indirect): Assays of progesterone or PAGs in blood/milk detect pregnancy around 28–30 days. These tests are pregnancy-specific and cheap per sample, but results take 1–4 daysand they do not show fetal viability. For example, PAG tests can predict ultimate calving rates by detecting late embryonic loss that ultrasound cannot.

Each method has trade-offs in timing, accuracy and labor. Table analyses show palpation works later (35–50 days) and costs little, whereas ultrasound can detect by ~28 days but costs more. Indirect tests are early and cheap but delayed by lab time. No single traditional method is ideal, but all require interpretation and, except for hormone tests, on-site examination.

Handheld Ultrasound Technology

Handheld ultrasound scanners are compact, battery-powered imaging systems that project sound waves into an animal’s body and display live cross-sectional images. These devices often connect to a tablet or smartphone (e.g. a Samsung device with a 3.5 MHz wireless probe) and are designed for farm use. Modern units are rugged and portable, with imaging depth (~10–20 cm) sufficient for most cattle, sheep, pigs, and goats. In practice, handheld scanners provide B-mode (2D) grayscale images of the uterus and fetus in real time. No radiation is involved, and scanning can be done quickly on awake animals in the barn. As one review noted, advances in design have made units “durable, waterproof, and easily operated by both vets and trained farmers”.

These portable machines bring ultrasound’s power onto the farm. Farmers can carry the probe and wireless display unit from pen to pen, using rechargeable batteries without cords. For example, a field study used a Samsung tablet and Clarius SV1 wireless probe (3.5 MHz sector) to scan sows for pregnancy up to ~25 days post-breeding. Such setups achieve image quality comparable to mid-range consoles, and devices are increasingly affordable as production grows. Handheld ultrasound is now common enough that market analysts forecast a doubling of the portable Veterinary ultrasound market by 2030.

Comparing Ultrasound to Traditional Methods

Handheld ultrasound essentially extends the capabilities of conventional ultrasonography while matching the convenience of on-farm testing. Key points of comparison include timing, information gained, and practicality:

• Timing: Studies show ultrasound can detect pregnancy as early as ~26–28 days after breeding. In cattle, fetal heartbeat may be visible by day 26, whereas palpation is not accurate before about day 35. A survey table confirms ultrasound detection around 28–30 days vs palpation after 35 days. Indirect PAG tests also flag pregnancy by day 28–30, but ultrasound yields instant results on the spot, avoiding lab delays.

• Information: Rectal palpation only indicates pregnant vs open and rough uterine size. Ultrasound imaging reveals more: number of embryos (twins or singles), fetal heartbeat (viability), and can image the ovaries and uterus for health issues. Hormone tests tell only pregnant/open, whereas ultrasound shows the actual conceptus. For example, ultrasound will image an embryo’s shape and heartbeat by ~30 days, something PALPATION cannot. Conversely, PAG tests may detect an embryo that ultimately fails, but ultrasound can immediately identify embryos that lack a heartbeat.

• Skill & Safety: Both palpation and ultrasound require trained operators. However, ultrasound is minimally invasive (only passes a transducer externally or rectally) and poses no known risk to a viable fetus. In fact, research suggests palpation in early gestation can increase embryonic loss, whereas ultrasound scanning (with care) is safer. Handheld scanners have made training easier by displaying clear live images; their portability helps operators scan multiple animals quickly. No special facilities are needed beyond handling chutes.

• Practicality: Traditional palpation needs no battery or capital equipment, whereas ultrasound devices cost more up front. Yet portable ultrasound adds convenience: it works in daylight and dirt, often has long battery life, and is repairable. Recent generations weigh just a few pounds and sometimes fold into a tablet form. For many farmers, the higher cost is offset by labor savings. In one dairy study, portable ultrasound reached cows (for pregnancy check) far faster than waiting for a palpation technician, “saving 10–15 open days per cow per year”. In short, handheld ultrasound combines the immediacy of palpation with the depth of information of a lab test, offering a more complete picture of each animal’s status.

Applications Across Livestock

Handheld ultrasound is used in cattle, pigs, sheep, goats and even exotic species. In cattle herds it is the go-to method: as soon as 28 days post-insemination a trained user can confirm pregnancy with a scan. In commercial swine operations, similar scanners (often with curved probes on a tablet) are used transabdominally; studies report >90% pregnancy detection sensitivity in sows by 21 days using this technology. In small ruminants (sheep and goats), transabdominal scans reliably detect pregnancy (and fetal count) by ~45–90 days of gestation. Veterinarians also use handheld units for other species (e.g. horses, alpacas), but the rapid pregnancy checks in herds are most widespread in food animals.

Globally, producers report major benefits. In North America, Europe and Australia, the adoption of real-time ultrasound has greatly increased diagnosis accuracy and herd productivity. For instance, U.S. cattle ranchers report a ~20% boost in pregnancy detection rates and better selection of replacement animals when using ultrasound compared to older methods. In places where veterinary resources are scarce, farmers have incorporated handheld units into routine work, or contract scanning services for entire regions. By eliminating guesswork (e.g. “observe and guess” breeding outcomes), ultrasound has become a cornerstone of herd reproduction programs worldwide.

Practical Benefits on the Farm

In practical farm terms, handheld ultrasound yields several key advantages:

• Timely Rebreeding: By confirming pregnancy at ~28–30 days (vs 35–45 days), non-pregnant females can be rebred sooner, reducing the unproductive interval. Quick action on open animals improves overall herd fertility.

• Economic Efficiency: Fewer open days and avoidable feed costs translate into savings. A Wisconsin farm study found that using ultrasound to identify open cows saved roughly 10–15 animal-days of upkeep per cow each year compared to palpation. Faster culling or reinsemination of open cows avoids wasted feed and housing expenses.

• Animal Welfare: Ultrasound scanning is minimally invasive and stress-free. Animals are only briefly restrained (often standing quietly), with no sedation or physical exertion. This improves welfare and reduces injury risk compared to chasing animals for palpation or pregnancy confirmation by rough means.

• Data-Driven Decisions: Scanning creates digital records (images, measurements). Farmers can track a fetus’s growth or identify issues (like fetal mummification or twin pregnancies) early. Such data helps tailor feeding programs (pregnant vs dry) and plan group management. For example, identifying twins early can change nutrition or handling for those ewes/cows.

• Versatility: Beyond pregnancy, the same handheld unit can diagnose other conditions (ovarian cysts, uterine infections, muscle evaluation, etc.), making the investment multi-purpose.

These benefits are not merely theoretical: farms using portable ultrasound routinely note faster decision-making and higher reproductive returns. One veterinarian reports that simply having an ultrasound on-site removes much of the guesswork, as “ultrasound allows producers to see inside the animal – safely, instantly, and with remarkable accuracy”.

Conclusion

Handheld ultrasound has redefined pregnancy detection in modern livestock production. By merging the early detection and diagnostic power of traditional ultrasonography with unprecedented portability, these devices make precise, on-farm pregnancy screening routine. Producers can identify open animals in time to rebreed them, verify twins or fetal health, and synchronize herd management around confirmed breeding dates. In effect, ultrasound scanning turns reproduction management from guesswork into data-driven science. As equipment costs fall and training spreads, more farms worldwide are expected to adopt handheld ultrasound as a standard tool, improving efficiency, animal welfare and profitability in livestock operations.

References:

• Balhara, A.K., Gupta, M., Singh, S., Mohanty, A.K. & Singh, I. (2014). Early Pregnancy Diagnosis in Bovines: Current Status and Future Directions. Veterinary Medicine International. PMC 3870866. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3870866/

• Pohler, K.G. et al. (2016). Past, present and future of pregnancy detection methods. Applied Reproductive Strategies in Beef Cattle (BeefRepro). https://beefrepro.org/wp-content/uploads/2020/09/21-pohler-251-259.pdf

• Parker, H. (2011). Three Benefits of Using Portable Ultrasound on a Dairy Farm. E.I. Medical Imaging (blog). https://www.eimedical.com/blog/bid/57619/Three-Benefits-of-Using-Portable-Ultrasound-on-a-Dairy-Farm

• Giles, R. (2020). Bovine Palpation vs Ultrasound. E.I. Medical Imaging (blog). https://www.eimedical.com/blog/bid/89522/bovine-palpation-vs-ultrasound

• Kim, T.-K. et al. (2025). Deep Learning-Enhanced Diagnosis of Sow Pregnancy Through Low-Frequency Ultrasound Imaging. Animals (Basel) 15(3):318. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC11815955/

• BXL Vet. (2025). Boosting Animal Health Through Real-Time Ultrasound Imaging on Farms. BXL Veterinary Technologies. https://www.bxlvet.com/news/boosting-animal-health-through-real-time-ultrasound-imaging-on-farms.html