When we talk about fertility in the cow, it is always worth having a quick refresher around what the normal cycle is. When we refer to the reproductive cycle we talk about a cow’s ability to produce a healthy egg every 21 days or within this range. This healthy egg is released into a small duct called the fallopian tube where it is wafted down to meet sperm and the process of fertilisation begins. Without this healthy egg, very little can happen. When the egg is released from the ovary, a hormone-secreting structure called a corpeus luteum replaces it. This produces progesterone which, if fertilisation occurs, supports the new embryo. If no fertilisation occurs, the corpeus luteum regresses and the cycle begins again. Many farmers will be familiar with a hormone called prostaglandin, which acts on the corpeus luteum to return a cow to cycle or bring a cow around. This will only work at certain times of the cycle.
A dairy cow can return to cycle quite quickly after calving – anywhere between 15 and 30 days is normal. A suckler cow can take longer, with the young suckling calf having a negative effect on the return to cycle.
By measuring calving interval we can judge the ability of a herd to get cows back in calf within a certain time period. The target for most herds will be fewer than 365 days, but there can be problems and most of these are problem cows that delay this calving interval.
What is a problem cow?
Problem cows are cows that do not return to heat or maybe have not been seen cycling at breeding time. They delay the annual calving cycle and often cost the farming system money. By identifying these cows early and going after them we can keep our reproductive performance on track and profitable.
The aim is to keep the breeding season compact, and we only have about three heats every 21 days to get our cows in calf. The longer these problem cows are not cycling or showing heats, the narrower this window becomes – down to two heats or even one. When we are chasing problem cows late in the summer, we are really losing money. So my key message is to chase the problem cows before breeding starts.
Where do I start?
Any herd can draw up a problem cow list right now. Through the law of averages and based on risk, some will struggle to return to cycling:
Cows that have had a hard calving.Cows that calved down twins.Cows that retained their cleanings or afterbirth.Cows that had milk fever or any illness such as mastitis or displaced stomachs.Cows that are in poor body condition after calving are potentially the biggest problems.If we pull these ladies out and get them examined pre-breeding it will be the beginning of getting them back into the system. My strong advice is to give them a full reproductive MOT – get their wombs scanned or scooped for any infections and scan the ovaries to see if they are cycling.
The problems and the treatments
Some of the common things we might see in these problem cows are:
1 Metritis or a dirty womb, where after calving these cows picked up uterine infections. Some cows can be quite sick with them. A lot of these cows with severe infections won’t be cycling. Even if they are, the environment for the sperm and the egg is unfavourable for fertilisation.
Treatment: these cows will typically receive a wash-out with antibiotics. I have tried all types of wash-out over the years and reverted to antibiotic preparations locally into the womb for the last number of years with the best results.
We should always aim to have herd levels of metritis well below 5% and should be asking ourselves why is it any higher. We need to be chasing the causes – usually energy imbalance, milk fever issues or selenium/vitamin E deficiency.
2 Cysts on the ovaries can cause problems. Either the follicle with the egg becomes cystic or the corpus luteum becomes cystic. With a cystic follicle you can often see erratic and more frequent heat patterns. With a cystic corpus luteum you will see no heats. Both of these can be treated by your vet with pretty good results once picked up early.
3 Acyclic, or in very simple terms nothing is happening, probably the most common finding in problem cows. This means there is no evidence of the cow starting to cycle.
Treatment: check body condition score and any other problems. By the fact they aren’t cycling, hormones would have had poorer results but it is worth considering a coil or CIDR. My advice with all these cows is once-a-day milking for three weeks also, regardless of the history, then a repeat scan in three weeks.
Nutrition the biggest driver
Feeding of the cow before and at breeding time is critical. This, along with genetics, has the greatest impact on ovulation of a healthy egg.
Cows in poor body condition that are under negative energy balance will not be cycling. Cows that lose a significant amount of body condition score between calving and breeding will not return to cycling.
Cows will be often be at peak milk yield around breeding time. Where you have thin cows, put them on once-a-day milking. This will drop production back to about 60% of capacity and allow these cows to balance out metabolically.
Right now is the time to pull out thin cows and put them on once-a-day milking for three to four weeks. For me, the best time to milk them is in the morning. Make sure they still get fed in the parlour in the evening if needed.
One other area where I have seen issues with nutrition is people underestimating grass or over-estimating how much milk production it is supporting. We just want to maximise intakes around this time of peak yield. The table above shows concentrates needed based on grass intakes.
Prebreeding tail paint and scanning
Having tail paint applied for three weeks before breeding allows farmers see what might not be cycling, particularly cows calved over five weeks. A pre-breeding scan with your vet of all these non-cycling, thin cows plus your list of problem cows is a great investment of time and money. Having done this for many farmers, you find that most cows will be cycling but you can pick up problems earlier and get these cows in calf quicker
A final word about hormones
Hormones are used to manipulate the cow’s ovarian cycle. They work well when timed correctly and most importantly used on cows cycling. A shot of prostaglandin will only work if there is a corpeus luteum present. These are expensive products, so administer carefully and correctly. Fixed-time AI or synchronisation programmes offer a fantastic way of tightening up your calving interval also.
So, fewer problem cows means more success. Go after the problem cows now to get them back in calf earlier. Remember, one of the most simple things you can do with problem cows is put them on once-a-day milking for three to four weeks with no impact on their overall lactation.
When we talk about fertility in the cow, it is always worth having a quick refresher around what the normal cycle is. When we refer to the reproductive cycle we talk about a cow’s ability to produce a healthy egg every 21 days or within this range. This healthy egg is released into a small duct called the fallopian tube where it is wafted down to meet sperm and the process of fertilisation begins. Without this healthy egg, very little can happen. When the egg is released from the ovary, a hormone-secreting structure called a corpeus luteum replaces it. This produces progesterone which, if fertilisation occurs, supports the new embryo. If no fertilisation occurs, the corpeus luteum regresses and the cycle begins again. Many farmers will be familiar with a hormone called prostaglandin, which acts on the corpeus luteum to return a cow to cycle or bring a cow around. This will only work at certain times of the cycle.
A dairy cow can return to cycle quite quickly after calving – anywhere between 15 and 30 days is normal. A suckler cow can take longer, with the young suckling calf having a negative effect on the return to cycle.
By measuring calving interval we can judge the ability of a herd to get cows back in calf within a certain time period. The target for most herds will be fewer than 365 days, but there can be problems and most of these are problem cows that delay this calving interval.
What is a problem cow?
Problem cows are cows that do not return to heat or maybe have not been seen cycling at breeding time. They delay the annual calving cycle and often cost the farming system money. By identifying these cows early and going after them we can keep our reproductive performance on track and profitable.
The aim is to keep the breeding season compact, and we only have about three heats every 21 days to get our cows in calf. The longer these problem cows are not cycling or showing heats, the narrower this window becomes – down to two heats or even one. When we are chasing problem cows late in the summer, we are really losing money. So my key message is to chase the problem cows before breeding starts.
Where do I start?
Any herd can draw up a problem cow list right now. Through the law of averages and based on risk, some will struggle to return to cycling:
Cows that have had a hard calving.Cows that calved down twins.Cows that retained their cleanings or afterbirth.Cows that had milk fever or any illness such as mastitis or displaced stomachs.Cows that are in poor body condition after calving are potentially the biggest problems.If we pull these ladies out and get them examined pre-breeding it will be the beginning of getting them back into the system. My strong advice is to give them a full reproductive MOT – get their wombs scanned or scooped for any infections and scan the ovaries to see if they are cycling.
The problems and the treatments
Some of the common things we might see in these problem cows are:
1 Metritis or a dirty womb, where after calving these cows picked up uterine infections. Some cows can be quite sick with them. A lot of these cows with severe infections won’t be cycling. Even if they are, the environment for the sperm and the egg is unfavourable for fertilisation.
Treatment: these cows will typically receive a wash-out with antibiotics. I have tried all types of wash-out over the years and reverted to antibiotic preparations locally into the womb for the last number of years with the best results.
We should always aim to have herd levels of metritis well below 5% and should be asking ourselves why is it any higher. We need to be chasing the causes – usually energy imbalance, milk fever issues or selenium/vitamin E deficiency.
2 Cysts on the ovaries can cause problems. Either the follicle with the egg becomes cystic or the corpus luteum becomes cystic. With a cystic follicle you can often see erratic and more frequent heat patterns. With a cystic corpus luteum you will see no heats. Both of these can be treated by your vet with pretty good results once picked up early.
3 Acyclic, or in very simple terms nothing is happening, probably the most common finding in problem cows. This means there is no evidence of the cow starting to cycle.
Treatment: check body condition score and any other problems. By the fact they aren’t cycling, hormones would have had poorer results but it is worth considering a coil or CIDR. My advice with all these cows is once-a-day milking for three weeks also, regardless of the history, then a repeat scan in three weeks.
Nutrition the biggest driver
Feeding of the cow before and at breeding time is critical. This, along with genetics, has the greatest impact on ovulation of a healthy egg.
Cows in poor body condition that are under negative energy balance will not be cycling. Cows that lose a significant amount of body condition score between calving and breeding will not return to cycling.
Cows will be often be at peak milk yield around breeding time. Where you have thin cows, put them on once-a-day milking. This will drop production back to about 60% of capacity and allow these cows to balance out metabolically.
Right now is the time to pull out thin cows and put them on once-a-day milking for three to four weeks. For me, the best time to milk them is in the morning. Make sure they still get fed in the parlour in the evening if needed.
One other area where I have seen issues with nutrition is people underestimating grass or over-estimating how much milk production it is supporting. We just want to maximise intakes around this time of peak yield. The table above shows concentrates needed based on grass intakes.
Prebreeding tail paint and scanning
Having tail paint applied for three weeks before breeding allows farmers see what might not be cycling, particularly cows calved over five weeks. A pre-breeding scan with your vet of all these non-cycling, thin cows plus your list of problem cows is a great investment of time and money. Having done this for many farmers, you find that most cows will be cycling but you can pick up problems earlier and get these cows in calf quicker
A final word about hormones
Hormones are used to manipulate the cow’s ovarian cycle. They work well when timed correctly and most importantly used on cows cycling. A shot of prostaglandin will only work if there is a corpeus luteum present. These are expensive products, so administer carefully and correctly. Fixed-time AI or synchronisation programmes offer a fantastic way of tightening up your calving interval also.
So, fewer problem cows means more success. Go after the problem cows now to get them back in calf earlier. Remember, one of the most simple things you can do with problem cows is put them on once-a-day milking for three to four weeks with no impact on their overall lactation.
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