Sexed semen lab to be established at Teagasc Moorepark: accelerating genetic gain and improving beef output from dairy herds

Dairy and beef production are inextricably linked. A dairy cow must have a calf to initiate lactation, but in all dairy herds the total number of calves born is greater than the required number of replacement females. Hence, in most herds, more than 70% of the calves born are destined for beef production, of which approximately 30% are male dairy calves.

The genetics of these male dairy calves have been selected for dairy traits, however, resulting in low economic value, as well as welfare and environmental concerns. With financial support from FBD Trust, a new project was launched at Teagasc Moorepark to use Bovine Assisted Reproductive Technologies to achieve two complimentary objectives:

1. Use sexed semen to generate female dairy calves and reduce the number of male dairy calves.
2. Use In Vitro Embryo Production (IVP) to accelerate genetic gain in both dairy breeds (Economic Breeding Index) and beef breeds suitable for crossing with dairy cows (Dairy Beef Index).

Sexing Technologies is the global leader in the production of sex-biased semen, and will establish a sexed semen laboratory at the Teagasc Moorepark Animal and Grassland Research and Innovation Centre, starting in November 2021. This lab will provide a semen sorting service open to all companies in the Irish AI industry. The presence of a sexed semen lab in Ireland will result in an increase in both the size of the team of bulls and the quality (EBI) of that team available to farmers (i.e., more bulls and higher EBI bulls selected for sorting). In addition, the presence of a sexed semen lab in Ireland will provide access to a key tool to facilitate genetic gain, as both X-sorted (female offspring) and Y-sorted (male offspring) semen will be potentially available from a wide range of bulls. With future use of sexed semen in dairy herds to generate heifer calves set to increase, there are three important consequences:

1. in the face of a marked decline in the number of male dairy calf births, an effective strategy is required to breed the next generation of elite breeding stock that are suitable to sustain or accelerate genetic gain in the national herd (measured by EBI);
2. in the context of a smaller proportion of the dairy herd being inseminated with dairy semen, greater efforts are required to breed the next generation of elite beef breeding stock that are suitable for crossing with dairy dams that are not suitable for generating replacements (measured by DBI);
3. with increasing scrutiny on the beef value of the calves from dairy dams with poor beef merit, it is necessary to investigate the feasibility of mass-producing beef embryos for transfer into dairy dams that are not themselves suitable to generate replacement heifers. This will facilitate generation of a beef calf with high economic value, being readily marketable to beef farmers.

A technology that would address all three of these objectives is In Vitro Embryo Production (IVP). Explaining how this works, Dr. Stephen Butler, Reproductive Physiologist at Teagasc, said that; “In Vitro Embryo Production involves collection of oocytes from either live donors, in the case of elite genetic merit dams, or from ovaries collected after slaughter in the case of commercial beef embryos. In all cases, the oocytes are fertilized and cultured in a lab for seven days before being transferred to a surrogate dam that has been synchronized to be on day seven of her estrous cycle. Using this technology, an elite genetic merit dam can be scheduled to have oocytes collected weekly for several weeks. This would facilitate the dam moving from having one calf per year to having multiple calves per year, and thus increasing the chances of producing a calf with greater genetic merit than the current generation.”

Commenting at the launch of the new laboratory facilities to develop this state of the art Bovine Assisted Reproductive Technology in Ireland, Michael Berkery Chairman of FBD Trust said that FBD was delighted to support this innovative development that offers immense commercial potential for the Dairy and Beef industries. He said; “commercialising the availability of sexed semen will greatly contribute to the sustainability of both the Irish dairy and beef industries, as this will help to stimulate a marked increase in the demand for sexed semen to generate replacement heifers. It will also stimulate greater usage of beef breed bulls in the dairy herd, thereby improving the financial value of the calf crop from the dairy herd. Following the recent phase of dairy herd expansion, this is critically important technology for the Irish dairy industry and I congratulate Teagasc for taking the initiative in establishing this Assisted Reproductive Technology Centre in Moorepark under the leadership of Dr. Stephen Butler”. FBD Trust has committed to providing financial support of €200,000 over the next four years to help get the project off the ground.

Also at the launch, the Teagasc Director, Professor Gerry Boyle highlighted that “like all the other sectors of our economy, the dairy industry must improve its sustainability credentials. Accelerating genetic gain, improving the efficiency of milk and meat production and meeting environmental and animal welfare targets are all simultaneously achievable by embracing the appropriate use of Assisted Reproductive Technologies”.

Professor Pat Dillon, Head of the Animal and Grassland Research and Innovation Programme at Teagasc noted that “the application of these new technologies has great potential for animal breeding, and there is a need to test and validate their performance in Irish grazing systems. Teagasc are very grateful for the financial support provided by FBD Trust to support this research”.