Video 15 summer scour syndrome
The most important thing to always remember first is common things are common. While I have been talking about this condition for a number of years, every calf not thriving in the early spring and summer is affected by this.
Worms and coccidiosis are still the big two issues for dairy calves in their first grazing season.
However, I noticed about six years ago a significant rise in these cases now often described as summer scour syndrome.
Symptoms
Typically calves would go backwards in the proceeding weeks after turnout or weeks after turnout.
There has been much debate about the cause but I’ve seen enough now to hang my hat on acidosis with potential factors at weaning contributing to the severity of the cases.
Usually, calves would begin scouring, have decreased appetite and start losing weight. I often heard farmers describe calves as “falling a apart” over a period of time. It can happen over a week to more slowly over a fortnight to three weeks.
On clinical exam, some of these calves would have ulcers in their mouths and show very little evidence of rumination.
A watery brown scour would be also often noted. It was interesting to watch them. They would stand with hunched backs, raised tails and zero evidence of rumination. The coats would typically be very dull also.
Potential causes
With calves at turnout with poor thrive, there would be a couple of things you would be thinking. Coccidiosis probably first and worms as the season progressed.
In some cases, molybdenumosis, where copper is being locked up, can also be a factor. Then more rarely giardia, rumen fluke and nemadtodirus. Also, trace element deficiencies can cause issues.
Remember these calves are immunosuppressed and they can pick up other infections easily also.
The important message I keep telling farmers is diagnostics can make a difference here.
While we like to run for a solution it is worth doing some FECs (faecal egg counts) to see what is present. The more samples the more evidence we have to work off.
In many cases when coccidiosis and worms were ruled out, I stood back and looked at the symptoms. I treated what I saw, which was acidosis.
These calves responded well to buffers +/- yeast, B vitamins and adding fibre to their diet. For the much poorer calves in the group back indoors on milk was an option. The worst calves affected could often be the younger ones that had been weaned quickly.
Typically I would see a high % of the group affected.
Research is ongoing and the link with possible new viruses like adenovirus being speculated. I think it is very clear what might be happening.
So what’s happening
If acidosis is a key symptom, we must look at the potential contributing factors.
There is some merit in looking at what calves are affected. If it is the later-born calves then weaning strategies need to be assessed. If the starter was high in starch this may also contribute to the conditions we see.
We must remember any time we change the diet we change the microflora in the rumen and they need about 2 weeks to adjust.
If that change is severe or acute we can have a change in rumen function often leading to a pH drop and acidosis. While calves do well on a high starch concentrate in early life, we must be mindful to have adjustments as they approach weaning to have it balanced with some fibre content as well. The big disruption can occur on some farms at turnout.
The big reasons in my opinion are
Spring grass is very high in oils like CLA (conjugated linoleic acid). To a young rumen, these can be hard to adjust to. We even see it in our adult dairy cows also to a lesser degree where rumen function can be altered at the beginning of the 2nd rotation with a flush of this lush grass.
Lush spring grass in lower covers also has very little fibre. This is an absolutely key substrate for good rumen health. Especially the young rumen of the calf.
Higher sugars and also potentially nitrogen can be hard on a young developing rumen. However, it is the low fibre and high oils, in my opinion, are the key drivers in this.
What are your options?
With many farms not having issues it should be business as usual but be mindful of these symptoms if they do appear.
For farms with issues yearly, things I have suggested was reviewing turnout dates and certainly look at where calves are going. Stronger covers suit these types of calves but may complicate grazing management strategies.
It can vary farm to farm with some people restricting grass in the diet for a period of months or putting calves on rougher ground. They maintain growth with concentrates and are careful about the constituents of the diet. Talk to your nutritionist here when formulating diets.
A simple thing any farm can do is have some roughage available from the word go and review weaning with regards to rumen health. While straw will work ok where it is chopped shorter it works even better. Some farms may decide to use a buffer through the meal for the first 6 weeks and this can work also.
I have found each farm to approach it slightly differently, but the key is to remember fibre is key and reduce the exposure to low covers of lush grass in the first 8-10 weeks.
It was interesting after the drought of 2018 I saw two cases of this which made me think again about time frames and the diet in the first year. A kg of meal doesn’t go astray in the first year at grass I feel. I know I’m not paying for the meal, but my opinion is it pays for itself.
So whats next
I think we are s lucky to be able to grow grass and feed livestock, it is this countries great advantage. We must always remember that we are feeding the rumen bugs and not the animal. Good rumen health is key to growth and performance. So knowing what the rumen wants should be a key focus of our grazing strategies of the future. For young calves, this means fibre and lower oil content. We must respect physiology and biology when broken they are hard to fix.
Thought for the day
Common sense isn’t always common, but it should be practised regularly and often. Common things are common and remember to keep things simple.
Huge thanks to Nettex in helping support me in making this series for more information click the link here http://www.net-tex.co.uk
Happy safe farming