Cows suffering from subclinical ketosis will take longer to return to oestrus and will be less likely to get pregnant, making ketosis one of the unseen factors driving down fertility on many farms.
With one-quarter of farms affected by ketosis in the UK, Elanco’s Kate Heller believes it could be suppressing fertility performance on a large-scale.
She says: “If you have issues with fertility, you should see if cows are suffering with ketosis, as it could be contributing to the problem.”
Ketosis is caused when cows go into extreme negative energy balance around calving and are forced to mobilise excess body tissue.
This leads to higher than acceptable ketone levels in the blood.
Energy balance is key to return to cyclicity, so on average, cows with ketosis take 22 days longer to return to service.
Energy balance also has a significant impact on the viability of the egg.
Ms Heller says: “Follicles that produce the eggs we serve at first service start to be produced in the transition period, so energy balance in transition and early lactation is key to the viability of the eggs.”
Ketones and fatty acids produced from the breakdown of body fat reserves are toxic to the eggs.
Consequently, Ms Heller urges farmers to establish their herd’s ketosis status, so steps can be put in place to curtail any issues that could be suppressing fertility.
Farmers can sign up for a free farm ketosis report carried out by a member of the Elanco team at farmanimalhealth.co.uk/SOTN.
The report looks at incidence and risk factors on-farm.
Actions, such as treating at-risk cows with a bolus three weeks from calving, can then be taken.
In the long run, regular ketone testing as part of milk recording can be a useful way to monitor ketosis levels.
Elanco currently analyses milk recording data from about 200 herds, representing 33,500 cows across England, Scotland and Wales. Analysing individual cow milk fat to protein ratio gives an indication of whether an animal may be affected by ketosis. A ratio of >1.4 suggests excess body fat may be being mobilised. The problem can then be investigated.
Visit the Ketosis State of the Nation Hub at FGinsight.com/KetosisSOTN
to find out what the ketosis incidence is in your region and view resources to help you manage the problem
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