“The use of fresh semen is up 6%, with over 200 AI technicians being supplied it over the last number of weeks.” This is according to Ross Hamilton of Progressive Genetics.

The fresh semen programme, which is run by Progressive Genetics and Munster Bovine, has grown in popularity over the last few years in Ireland.

Speaking about the benefits of fresh semen, Ross said: “The advantage of fresh semen is you can produce more straws for the highest genetic merit sires to meet the peak seasonal demand on one hand while using fresh semen simplifies the on-farm insemination process.

“However, fresh semen has a limited shelf life, unlike frozen semen, so a high demand is required to justify the rollout of the programme.”

The fresh semen programme kicked off on Wednesday, April 15, and it is due to wrap up on June 1.

To find out the ins and outs of the fresh semen programme, AgriLand spoke with Dr. Ciara O’Meara, who works in the National Cattle Breeding Centre in Naas, Co. Kildare.

What’s involved in it?

Talking to AgriLand about the process involved in harvesting fresh semen, Dr. O’Meara said: “Semen is collected from the chosen bulls each Monday, Wednesday and Friday. It is then processed; stored at room temperature; and distributed around the country.

“At the moment, 20 bulls are being ‘jumped’ for fresh semen.

“The process of semen collection and transportation to the central laboratory is almost the same as for conventional frozen semen, except we use a different semen extender which can maintain cell viability for a number of days at room temperature – ideally between 15º to 20°.

Due to Covid-19 this year, we have a specific designated ‘fresh semen production’ laboratory.

“From there, we measure semen volume and assess concentration in order to determine our fresh semen dilution rate.

“Furthermore, we check the semen quality for total and progressive motility: on arrival to the laboratory; after filling into semen straws; and again on each of the next three mornings.

“The straws used for fresh semen are slightly different to frozen semen straws and the labelling on the straws is also slightly adjusted. The main difference being, we don’t include barcoding and indicate clearly that it is a fresh straw.

“We package the straws into a temperature-regulated box at 17° and dispatch them to AI technicians for further dissemination in the field.

“Moreover, we monitor and record in vitro motility daily, while the bull straws are still in use.”

Can any bull be used for the programme?

When asked if any bull can be used for the programme, Dr. O’Meara replied by saying no, citing that certain criteria have to be met in order for a bull to be used.

She explained: “A number of factors come into play when deciding what bulls are to be used. The selection process can take up to a couple of months.

“Bulls are chosen on the basis of: what customers are looking for; genomic assessments from the most relevant genomic data on a bull’s economic breeding index (EBI); their semen production capacity; their semen quality over time; and field fertility.”

What are the advantages/disadvantages of fresh semen over frozen semen, if any?

Speaking about the advantages and disadvantages of fresh semen compared to frozen semen, Dr. O’Meara said: “The dilution rate for fresh semen is higher than conventional semen, which allows us to produce more doses of high-demand bulls.

“The benefits are really with maximising output and having the availability of semen from the top EBI bulls to meet customer requirements during peak demand.

The advantages of fresh semen for the AI technicians is that there is no thawing of the straws necessary, which helps to simplify and speed up the process on the farm.

“The straws are stored at room temperature, so liquid nitrogen is not required. Another advantage is that the AI technician will have access to scarce high genetic merit bulls for his customers.

“The top genetic merit sires are often young bulls due to the use of genomics. However, these bulls do not have the capacity to produce large quantities of semen in advance of the breeding season, so by employing fresh semen technology we can make these bulls available to more farmers during the spring compared to what would be possible with frozen semen.

“The only disadvantage of fresh is that the sperm only survive for a finite amount of time and we start to see a decrease in fertility after three days. Therefore, we recommend straws are used within this time-frame.”