With a huge interest in sexed semen and increased use of high beef merit bulls, dairy farmers are taking steps to protect their farm businesses from the vagaries of the calf trade.
The conventional approach to breeding in the dairy herd is to use dairy AI for five or six weeks followed by another five or six weeks of a beef stock bull.
In this situation, a high proportion of the calves born are dairy bull calves whose main market is mainland Europe.
Weather and other issues outside of farmers’ control mean the live transport of these calves can often be disrupted which leads to demand and prices falling.
There is also more regulatory pressure coming on the live transport of unweaned calves, thus moves by the industry to investigate flying calves overseas as a way to reduce travel times and stress on calves.
The quality of beef calves from the dairy herd is another issue that often comes up. The typical beef stock bull is failing to deliver the quality of calf required in terms of carcase size. Higher beef merit AI bulls will deliver much higher beef merit calves which are sought after by astute calf buyers.
On the face of it, sexed semen has the potential to deliver solutions to all of the issues identified above.
Using sexed dairy semen on fewer cows to deliver the required amount of dairy replacement heifers means that more cows can be inseminated with high merit beef AI bulls.
This means far fewer dairy bull calves for shipping and far more beef calves with a variety of market options.
Sexed semen
While the choice of bulls available for sexed semen has increased dramatically, there are still drawbacks in terms of cost and conception rate.
The golden rules of sexed semen must be adhered to fully in order to minimise the reduction in conception rate. These rules are:
Cows selected should be between lactation one and four.Cows should be more than 50 days in milk on the day of AI.Cows should have a body condition score of greater than three.Cows should be cycling regularly prior to inseminationCows should be free of disorders such as lameness, mastitis and uterine infections.Even where these rules are followed, some reduction in conception rate is to be expected compared to conventional semen. Therefore, sexed semen should only be used in the first part of the breeding season to minimise the impact.
The Teagasc advice is to use sexed semen in the first three weeks or, ideally, in the first 10 days.
The rules around using sexed semen will limit what cows are available for being sexed anyway, but the timing of AI is also a key consideration.
Essentially, a longer time period between the onset of heat and insemination is required for sexed semen. This is because sexed semen is a distorted product and therefore has a shorter shelf life in the uterus. Inseminating the cow later than one would with conventional semen means that there is more sperm activity at ovulation.
The ideal time for inseminating with sexed semen is 14 to 20 hours after the onset of heat, which is the first time the cow was mounted. This has knock-on effects for those using once-a-day AI because if the cow is seen bulling for the first time in the morning, it shouldn’t be inseminated with sexed semen until later that evening or early the following morning.
Those who want to use a high proportion of sexed semen must be practising AM-PM AI and must be good at heat detection so they know when the cow came on to heat and can plan AI accordingly.
Over the next few weeks, farmers should be selecting cows in the herd into two panels – one for sexed semen and one for beef.
The sexed semen panel should contain cows that tick all of the boxes for sexed semen suitability, plus one key factor which is to be high EBI.
There is some confusion out there as to where to go to identify good cows from bad cows
As these cows are the ones that will be breeding future cows in the herd, they must be good cows.
There is some confusion out there as to where to go to identify good cows from bad cows. I hear of some farmers looking through the milk recording results to identify the good cows going to get dairy AI and the bad cows going to get beef AI.
There are a few golden rules to be followed when using sexed semen. \ Donal O'Leary
The problem with this is that there is more than just genetics at play when it comes to milk performance.
For example, take two cows; one with an EBI of €100 and one with an EBI of €200. As a calf, the higher-EBI cow got pneumonia, which resulted in her having stunted growth that still affects her performance.
Milk recording
On the milk recording results, the lower-EBI cow outperforms her.
Presuming both cows are inseminated with the same high-EBI bull and both have a heifer calf, which calf would you expect to perform better as a cow?
The higher-EBI calf should perform better even though her dam doesn’t perform as well as the lower-EBI cow. Therefore, EBI should be used to select which cows are to get dairy AI and which are to get beef.
Alongside using a panel of dairy AI bulls, farmers should also use a panel of beef AI bulls if they are to maximise the beef value of the calves.
Easier-calving beef bulls should be used on first-lactation cows, but a third- or fourth-calver should be well able to handle a harder calving but higher beef value bull. Most of the AI companies have options for each age category.
Where to now for
those crossbreeding?
The introduction of genotyping and the commercial beef value (CBV) presents an opportunity for farmers who use high beef merit bulls to be rewarded in the market, even in crossbred herds with Jersey in the background and a JEX or FRX on the blue card.
The CBV of a calf is made up of half the beef merit of the dam and half the beef merit of the sire.
Cows with a low beef merit, such as Jersey crossbreds, will need to be crossed with beef bulls with a higher beef merit – the beef part of the dairy beef index (DBI) – in order to have a high CBV. Calf buyers must “buy into” the CBV and reward all farmers who are breeding high-CBV calves by paying more for them and less for lower CBV calves.
With genotyping, they should have full confidence in the parentage of the calves. Of course, herds with higher beef values in the EBI will find it easier to breed high CBV calves.
With a huge interest in sexed semen and increased use of high beef merit bulls, dairy farmers are taking steps to protect their farm businesses from the vagaries of the calf trade.
The conventional approach to breeding in the dairy herd is to use dairy AI for five or six weeks followed by another five or six weeks of a beef stock bull.
In this situation, a high proportion of the calves born are dairy bull calves whose main market is mainland Europe.
Weather and other issues outside of farmers’ control mean the live transport of these calves can often be disrupted which leads to demand and prices falling.
There is also more regulatory pressure coming on the live transport of unweaned calves, thus moves by the industry to investigate flying calves overseas as a way to reduce travel times and stress on calves.
The quality of beef calves from the dairy herd is another issue that often comes up. The typical beef stock bull is failing to deliver the quality of calf required in terms of carcase size. Higher beef merit AI bulls will deliver much higher beef merit calves which are sought after by astute calf buyers.
On the face of it, sexed semen has the potential to deliver solutions to all of the issues identified above.
Using sexed dairy semen on fewer cows to deliver the required amount of dairy replacement heifers means that more cows can be inseminated with high merit beef AI bulls.
This means far fewer dairy bull calves for shipping and far more beef calves with a variety of market options.
Sexed semen
While the choice of bulls available for sexed semen has increased dramatically, there are still drawbacks in terms of cost and conception rate.
The golden rules of sexed semen must be adhered to fully in order to minimise the reduction in conception rate. These rules are:
Cows selected should be between lactation one and four.Cows should be more than 50 days in milk on the day of AI.Cows should have a body condition score of greater than three.Cows should be cycling regularly prior to inseminationCows should be free of disorders such as lameness, mastitis and uterine infections.Even where these rules are followed, some reduction in conception rate is to be expected compared to conventional semen. Therefore, sexed semen should only be used in the first part of the breeding season to minimise the impact.
The Teagasc advice is to use sexed semen in the first three weeks or, ideally, in the first 10 days.
The rules around using sexed semen will limit what cows are available for being sexed anyway, but the timing of AI is also a key consideration.
Essentially, a longer time period between the onset of heat and insemination is required for sexed semen. This is because sexed semen is a distorted product and therefore has a shorter shelf life in the uterus. Inseminating the cow later than one would with conventional semen means that there is more sperm activity at ovulation.
The ideal time for inseminating with sexed semen is 14 to 20 hours after the onset of heat, which is the first time the cow was mounted. This has knock-on effects for those using once-a-day AI because if the cow is seen bulling for the first time in the morning, it shouldn’t be inseminated with sexed semen until later that evening or early the following morning.
Those who want to use a high proportion of sexed semen must be practising AM-PM AI and must be good at heat detection so they know when the cow came on to heat and can plan AI accordingly.
Over the next few weeks, farmers should be selecting cows in the herd into two panels – one for sexed semen and one for beef.
The sexed semen panel should contain cows that tick all of the boxes for sexed semen suitability, plus one key factor which is to be high EBI.
There is some confusion out there as to where to go to identify good cows from bad cows
As these cows are the ones that will be breeding future cows in the herd, they must be good cows.
There is some confusion out there as to where to go to identify good cows from bad cows. I hear of some farmers looking through the milk recording results to identify the good cows going to get dairy AI and the bad cows going to get beef AI.
There are a few golden rules to be followed when using sexed semen. \ Donal O'Leary
The problem with this is that there is more than just genetics at play when it comes to milk performance.
For example, take two cows; one with an EBI of €100 and one with an EBI of €200. As a calf, the higher-EBI cow got pneumonia, which resulted in her having stunted growth that still affects her performance.
Milk recording
On the milk recording results, the lower-EBI cow outperforms her.
Presuming both cows are inseminated with the same high-EBI bull and both have a heifer calf, which calf would you expect to perform better as a cow?
The higher-EBI calf should perform better even though her dam doesn’t perform as well as the lower-EBI cow. Therefore, EBI should be used to select which cows are to get dairy AI and which are to get beef.
Alongside using a panel of dairy AI bulls, farmers should also use a panel of beef AI bulls if they are to maximise the beef value of the calves.
Easier-calving beef bulls should be used on first-lactation cows, but a third- or fourth-calver should be well able to handle a harder calving but higher beef value bull. Most of the AI companies have options for each age category.
Where to now for
those crossbreeding?
The introduction of genotyping and the commercial beef value (CBV) presents an opportunity for farmers who use high beef merit bulls to be rewarded in the market, even in crossbred herds with Jersey in the background and a JEX or FRX on the blue card.
The CBV of a calf is made up of half the beef merit of the dam and half the beef merit of the sire.
Cows with a low beef merit, such as Jersey crossbreds, will need to be crossed with beef bulls with a higher beef merit – the beef part of the dairy beef index (DBI) – in order to have a high CBV. Calf buyers must “buy into” the CBV and reward all farmers who are breeding high-CBV calves by paying more for them and less for lower CBV calves.
With genotyping, they should have full confidence in the parentage of the calves. Of course, herds with higher beef values in the EBI will find it easier to breed high CBV calves.
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