Vet's corner: CCN, cow bloat and pneumonia all in one week

With the sun shining and silage being made, the calls are definitely decreasing. Last week, I got a call to a calf with meningitis. On arrival, I examined the calf – a three-month-old Friesian heifer that was staggering. On clinical examination, the calf was stretching its head up and backwards. On closer examination, the calf appeared blind. The calf had a condition we refer to as CCN (cerebrocortical necrosis), brought on by a thiamine deficiency, more commonly known as a B1 deficiency.

These calves had come off concentrates and were moved to fairly lush pasture five days previously. A B1 deficiency can often be brought on in younger calves by a dietary change, especially where abnormal ruminal fermentation produces thiaminases. These break down B1, leading to low blood levels that affect the brain. B1 has a role to play in glucose production, which results in these symptoms. This calf’s symptoms were classical for this condition.

We treated the calf with IV B1 and also followed up with six-hourly injections for 36 hours. He also got a steroid to reduce cerebral swelling. It was brought in and penned up to prevent any injuries due to the blindness. The next day, it had responded well. We discussed putting the calves back on to concentrates and also changing from the current pasture. CCN can always be a risk in calves and lambs two to six months of age where there is a sudden change of diet.

Urgent call

This morning I got quite an urgent call to a cow with bloat. The cow had been out grazing that morning and a keen eye spotted her. She was hugely distended on both sides, but particularly the left where her main stomach or rumen is. We diagnosed an acute gassy bloat.

There are two types of bloat:

Both types of bloat are an emergency, but treatments vary slightly. The first thing I did with this cow was insert a stomach tube to relieve the gas. I then gave some oral medications to settle its rumen, along with a painkiller. We didn’t find the cause of the bloat, but it may have occurred due to some sort of blockage. She recovered well. Time is not on your side with severe bloating, so these are real emergency cases.

Pneumonia

Finally, one other issue I have seen in two flocks of sheep in the last week is pneumonia in lambs.

On both farms, I did post-mortems on the lambs they lost in the last two weeks, which revealed pneumonia as the most likely cause of death. When we examined both flocks, we spotted that the lambs had lost condition, with some running temperatures and with increased respiratory rates at rest.

In the first flock, which had more severe symptoms, we treated all lambs with a long-acting antibiotic and suggested vaccinating them in four to five days, depending on their response to treatment. This was simply due to the fact that more than 60% of the lambs were affected.

In the second flock, we only treated the sick lambs. Those without a temperature which looked healthy received the first shot of a pasteurella vaccine. Less than 10% of this flock was affected.

In my experience with pneumonia, pasteurella in particular seems to be an issue in flocks at this time of year. Of course, it is worth remembering to check for any other causes of immunosuppression that might be playing a role, such as parasites, etc.

Neither flock has reported any more losses, so it looks like treatments have worked so far. However, there is no doubt that lamb performance is affected and they will take time to get back on track.

Read more

Vet’s corner: A rare case of two cows with heart problems