I was on two dairy farms on Tuesday this week and both farmers just had the vet in the yard treating a case of suspected ketosis. On the first farm the cow was a third-calver which had been dried off in early November and had calved down in a good condition score of at least 3.5. The farmer noticed something wrong when the cow, one week after calving, came into the parlour off-form and with not much milk. Her eyes had sunk in and she was slow to react to any movement.

On the second farm the cow in the crush was a fifth-calver who had again been dried off in late October and had calved down in the second week of February. Two weeks later (this week) she came in for milking and the farmer noticed she was off-form – slow to move around the yard and standing at the back of the collecting yard in a world of her own.

Ketosis is a signal that the cow is in negative energy balance and this happens when output exceeds input or, in other words, when she is milking more than the energy she is consuming. Clinical ketosis (cows actually showing signs like the two cows above) is reported to be less than 2 to 5% but vets often suggest that prevalence of sub-clinical ketosis (no sign of sickness) can suppress the immune system and open the door to other problems such as retained placentas, metritis and displaced abomasums. Vets also say research shows cows that get sub-clinical ketosis are slower to come back in heat by up to 30 days.

Prevention

One of the most important issues in freshly calved cows is to try and keep feed intakes up after calving.

This can be very difficult on cows that calve down over-fat so be very careful feeding too much high-quality feed to late March-calving cows. Fat cows reduce intakes considerably before calving.

Another very simple thing you can do is to ensure dry cows have enough feed space because if you have limited feed space it can often be the trigger for reducing intakes and hence lower energy.

Indicators of negative energy balance include high incidence of ketosis, retained placentas, displaced abomasums, high milk fat to milk protein ratio (over 1.5 ratio – so this means results such as a fat of 4.5% and protein of 3% should send an alarm signal) and low milk yield post calving.

New test

Elanco Animal Health recently introduced a cow-side milk test, Keto-test™. I met Elanco vet Francis Cosgrove earlier this spring and he stressed clinical symptoms in a few cows could represent the tip of a very large ketosis iceberg.

He said: “We feel it is vital to test for subclinical ketosis in cases of reduced fresh cow performance and the development of what are most likely to be ketosis-related post calving, health disorders. Our new Keto-Test allows the immediate identification of the metabolic disorder using milk stripped from individual cows.

Both high risk herds and individual high risk cows can be identified using the test.” The cost of the Ketotest is approximately €45 for 20 cow tests.

Up to now, blood samples were the key to testing for ketosis but now individually testing milk from fresh cows is possible. High-risk cows are cows that have twins, fat cows and heifers calving down for the first time at 28 to 30 months old.

For both farms I was on this week the vets recommended drenching the cows with propylene glycol to try and improve energy levels and taking the cows out into a paddock near the yard where they had access to grass and forage and were not in competition for feed with other fresh calvers. Research suggests drenching cows with glycol increases insulin by 200-400% within 30 minutes after drenching. It also increases plasma glucose.

When I was speaking to Francis Cosgrove he said they also had a bolus that is authorised to reduce the incidence of ketosis.

The bolus is called Kexxtone (monensin sodium) and he said some farmers use the slow-release bolus on high-risk cows such as over-fat cows at calving. The bolus minimises the risk of negative energy balance over 95 to 100 days and costs €45 to €50 per bolus.

Ketosis costly when undetected - read more here.