Semen testing may be of interest for producers looking for peace of mind when it comes to herd fertility. And new tech means they can take a close – and objective – look at semen quality on farm.
TEXT JULIETTE MCDANIEL
There are a handful of scenarios for a semen fertility test or analysis, including checking a bull before breeding season, or a sale, or to ensure semen straws stored in a liquid-nitrogen tank, which are often sent from a bull stud to be stored on farm then used for artificial insemination at a later date, still have good motility.
While most vets and breeding technicians can examine semen samples taken from bulls or AI straws under a microscope, this traditional analysis is subjective and relies on a trained eye.
Aware of the drawbacks of this process, and looking to overcome them by creating more reliable and accurate technology, Vincent Martinez set out to develop a fully portable semen analyser.
Dynescan is the result of his work and, since its launch in 2022, is now being used by producers across six continents. The technology, which has also won several awards, has analysed more than 4,000 samples and is building up a strong data set across a variety of beef and dairy breeds.
“There is so little known about fertility because, until now, the on-farm analysis process up has been subjective,” explains Dr Martinez.
“It requires technological accuracy and measurements that producers can rely on to make breeding decisions. Current technologies only work for a narrow range of concentrations, which creates added complications when testing fresh or sex-sorted semen.
Semen analysis
“So we developed an automated and portable instrument for semen analysis, which works across a wide range of concentrations, from one million sperm cells per millilitre to around 500 million. It can also analyse sex-sorted and conventional semen straws, as well as diluted fresh semen, providing measurements with errors of less than 5%.”
AHDB reports that 76.5% of dairy semen sold in the UK in 2023 was sex-sorted, making this technology more applicable today than 20 years ago, when it only accounted for 15% of sales.
“Fertility efficiencies are vital for successful herd management. Producers need to understand the effect semen performance can have on conception rates and profit margins when breeding herd replacements,” adds Dr Martinez.
“The real power of this semen analysis technology is that it can monitor performance over time. So this becomes the first machine capable of measuring the lifetime of semen motility, essentially seeing how long it can swim for and in conditions similar to the reproductive tract,” he explains.
Semen sample: loading a test slide
Metabolic health
In continuous-measurement mode, the equipment collects data at regular intervals during a two-hour period.
“It can measure speed and percentage of motility, which gives an insight into the metabolic health of the sperm cells. The motility should not change during this time, but we see some samples where it plummets. The sperm cells are unable to handle the low-oxygen conditions, which are similar to those experienced in cows’ reproductive tract.”
He says that this semen-performance insight is key to explaining poor conception rates, which would not otherwise be picked up on a quick visual assessment of a semen sample. “So can producers be sure that the existing method of semen analysis is telling them much?” he asks.
Data collected by the Dynescan technology has enabled Dyneval to create its own fertility marker, called sustained motility lifetime (SML). This is the time period during which the initial percentage of progressive motility halves, providing new insights into whether semen motility is likely to be sustained within the cow.
In 2023, independent vets took measurements using the technology and compared these with conception rates in the field. Testing more than 2,000 inseminations and 22 batches of semen, the research showed that if the semen could sustain motility well for more than two hours, conception rates were 8% higher. Recent results received from Argentina indicate an improvement of 10%, corroborating this finding.
“In a commercial herd environment, having a clearer picture of semen quality helps to support accurate planning, tighter calving patterns and more effective breeding strategies. It will, ultimately, allow businesses to improve efficiency and sustainability,” says Dr Martinez.
“A conception rate increase of just a few percentage points can add up across the herd and, for the sake of sacrificing one straw within each batch, it could offer significant cost savings. For some producers accurate testing will mean peace of mind, but it could reveal areas that require improvement, such as semen straw storage or transport.”
Dynescan can also be a useful tool for assessing damage to semen straws during transport and storage. Research shows that straws can be damaged by lifting them out of AI flasks for only 10 seconds, reducing progressive motility by 11%.
Tank checks
Semen quality is key to AI success. “So not only is it essential to ensure that it is performing as expected, but it is also important to maintain the integrity of liquid nitrogen tanks to safeguard this investment,” he says.
“Substantial degradation of semen quality decreases conception rates, so regular tank-health checks and training are imperative to mitigate risks.”
One of the newest services available from Dynescan is the tank auditing tool, which is used to test tank integrity and safety. The audit allows vets and AI technicians to evaluate storage conditions and semen performance.
As part of the audit, testing a single straw, representing each batch, is required. Any changes in the quality over time will alert tank owners to address potential causes promptly before further deterioration occurs.
“This technology is slowly making its way onto dairy units, via vets who are using it to improve the accuracy of the semen-analysis service they provide to their producer customers,” explains Dr Martinez.
“The awareness of the need for accurate data on semen quality, herd fertility and conception rates is increasing, and will continue to do so as producers continue to strive for greater efficiencies.”
Producers interested in using Dynescan, via their vet, should fill out the form at: www.dyneval.com/tell-your-vet.
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