24 October 2023
Selecting AI sires for autumn breeding on Future Beef farms
A number of farmers enrolled in Teagasc’s Future Beef Programme operate either entirely autumn-calving or a combination of spring and autumn-calving herds. In this article, Aisling Molloy, Future Beef Programme Advisor, looks at sire selection on a number of the farms enrolled.
Eamon and Donnchadh McCarthy
Farming in Carrigeen, Glendine, Co. Waterford, father and son team Eamon and Donnchadh McCarthy will start breeding their autumn herd on October 5th. 12 cows have been selected for breeding to maternal bulls and 12 cows will be bred to more terminal bulls.
The maternal bulls selected are: SI4147; SI4250; AU4683; and SA4604. The five heifers and seven cows selected for breeding to maternal bulls have a minimum Replacement Index value of €123, which stretches up to €184.
Their daughter milk figures range from 3.6kg to 18.2kg and the carcass weight ranges from -2.3kg to 31.6kg. The bulls selected are individually chosen to produce a replacement that is better than its mother, so if she is low in milk a bull with a higher milk index will be used etc.
SI4147 (Curaheen Gunshot P) has a Replacement Index Value of €170. He has a daughter milk figure of +8.2kg and a daughter calving interval of -3.48 days. Carcass weight is good at 32.9kg and the cow calving difficulty is 7.2%.
SI4250 (Lis-Na-Ri Gucci) has a Replacement Index of €161, with a daughter milk figure of +6.4kg and a daughter calving interval of -3.56 days. The carcass weight figure is 19.4kg and the beef cow calving difficulty is 3.1%.
AU4683 (Turloughmore Magnificent) has a Replacement Index of €209. His daughter milk figure is +3.2kg and the daughter calving interval is -7.76 days. He can be used on the milkiest cows in the herd, as he does not add as much milk as the previous bulls. His carcass weight is 18.8kg and he has a beef cow calving difficulty of 2.7%.
SA4604 (Knottown Roy) has a Replacement Index of €241, which consists of a daughter milk figure of +8.3kg and daughter calving interval of -6.58 days. His carcass weight is 20.5kg and the beef cow calving difficulty is only 1.8%.
Terminal bulls
A total of 11 animals have been selected for breeding to terminal bulls – one heifer and 10 cows. Their Replacement Index values ranged from €30 to €130. The bulls being used on the cows breeding terminal calves are SI2152, CH4321 and CH7503.
SI2152 (Curaheen Earp) is often used as replacement bull, as well as for his terminal traits. He has a Terminal Index of €91 with a carcass weight of 22.8kg and carcass conformation of 1.56. His beef cow calving difficulty is 3.6%.
CH4321 (Lapon) has a Terminal Index of €160, with a beef cow calving difficulty of 5.1%. He has a figure of 41.8kg carcass weight and 2.26 carcass conformation.
CH7503 (Cloonradoon Ricky) has a Terminal Index of €123, a carcass weight of 35kg and a carcass conformation of 2.13. His beef cow calving difficulty figure is 9.1%, so he will be used on more mature cows that have lower terminal traits.
For more information on the McCarthy’s herd, including an update on the spring-calving herd, animal health and animal performance, click here.
Ken Gill
Ken Gill’s breeding season will start on October 30th this year. Ken, who farms in Clonbullogue, Co. Offaly, plans to stick with a six-week breeding season and aims to have 70 cows calving next autumn.
Due to a high replacement rate of 30%, he will have to breed 42 cows to maternal bulls in the hope of having 21 potential replacement heifers born. Due to the extra in calf heifers this year, Ken has 102 potential replacements to breed from. However, some of these have been selected for culling due to being very thin, having big udders, losing a calf or difficult calvings. He culled hard last year for mastitis and temperament and so far has not chosen any culls for either reason.
Sires for use on heifers
He has selected two Angus bulls, AA4640 (HW Farghal T516) and AA4303 (Lisduff Red Pepper R368), for breeding with his heifers. These have: Replacement Index values of €119 and €170, respectively; a beef heifer calving difficulty of 6% or less, with over 96% reliability; daughter milk of 10.5kg and 8.7kg, respectively; and a carcass weight figure of over 14kg to increase the herd average, which is 10kg. The aim is that the heifers will be potential replacements, but the bulls will still have good terminal traits for finishing.
Maternal bulls
The replacement bulls selected are AU4683, LM4351, SI4083, CH4202, LM4302 and SA2189. The Replacement Index values of these sires range from €155 to €209; beef cow calving difficulty is less than 6% at over 97% reliability; the daughter milk figure ranges from 3.2kg to 9.1kg; and the daughter calving interval is -0.72 days to -7.76 days. Additionally, the carcass weight figures for the replacement bull team selected range from 18.8kg to 40.2kg, with carcass conformation of 1.05 to 2.29. All of these sires have been choose to further improve the breeding potential of the herd.
Terminal bulls
The cows selected for breeding to more terminal bulls have a Replacement Index value of less than €124. The bulls chosen are AA4087, BJG and AA4303. They have a Terminal Index of €86 to €105; a carcass weight figure of 14kg to 25.1kg; carcass conformation of 0.93 to 1.12; and are less than 4.6% calving difficulty for beef cows at over 96% reliability.
For more information on Ken Gill’s farm, including a calving update, slaughter performance of 2021-born cattle, and farm safety, click here.
Eamon and Donnchadh McCarthy and Ken Gill are participants in Teagasc’s Future Beef Programme. To learn more about the programme and to sign up to regular updates from the farms enrolled, click here.