27/08/2026
Do you leave the scouring calf in the pen, or take it out?
This was the decision weighing on me yesterday.
I had calves scouring, but I did not have calves that looked sick.
They were warm, hydrated and drinking. They stood easily, had a good suck and were still interested in everything happening around them. Their poo had changed, but the calves themselves had not noticeably changed.
I was also seeing calves in several different pens following the same trajectory. Those pens were separate and different groups of calves, but they had all experienced the same disruptions and inconsistencies in feeding.
That pattern made me more confident this was a situational response to what had happened with their feeding, rather than an infection simply passing from one calf to the next.
More confident, but never completely certain.
That is what makes this decision difficult. There genuinely is not one completely right answer.
The science says there are very good reasons to remove a scouring calf from the pen.
Most infectious scour pathogens spread through the faecal-oral route. A calf does not need to deliberately eat poo. Tiny amounts move on bedding, boots, teats, feeders, water, hands and other calves.
A single infected calf can shed enormous numbers of organisms. Rotavirus can be heavily shed for several days. Cryptosporidium oocysts are produced in huge numbers and survive well in the environment.
Even if the other calves have already been exposed by the time I see the scour, the amount of exposure still matters. Leaving that calf in the pen means it continues adding infectious material to the environment.
Removing it may lower the challenge for the calves around it. It also allows me to see exactly what the infected calf drinks, treat it without competition and notice quickly if it begins to deteriorate.
That is a strong argument for isolation.
But then I have to look at what removal means on my farm.
My isolation bay is not inside the greenhouse. I would be taking a calf out of its environment, away from familiar pen-mates and the feeding setup it understands, and putting it into a noticeably different climate.
Calves are also social animals. Research into calf housing has found that socially housed calves generally eat more starter, cope better with change and are less fearful than individually housed calves.
That research does not specifically prove that a scouring calf will recover faster if I leave it with its mates. But it does tell me that removing a calf from everything familiar is not a consequence-free decision.
So I was standing there with two perfectly valid concerns for 8 calves across 3 pens.
If I left these calves where they were and I was wrong about the cause, I could increase the infectious challenge for the rest of the group.
If I moved them and I was right that this was a response to feeding inconsistency, I would be adding another change, another feeding setup, social separation and a climate shift to calves that were still otherwise coping.
Neither option felt entirely comfortable.
The appearance of the poo could not make that decision for me either.
Diarrhoea is a sign, not a diagnosis. Veterinary science describes everything from loose faeces in an otherwise healthy calf through to dehydration, acidosis, weakness, depression and collapse.
The amount of liquid coming out the back does not neatly tell us how systemically sick the calf is. I need to look at the whole calf.
Is it bright?
Does it stand easily?
Is it warm?
Is it hydrated, or are its eyes sinking and its skin beginning to tent?
Is it drinking its normal volume with a strong suck?
Is it steady on its feet?
Is it continuing to compete comfortably within the group?
Then I look beyond the individual calf.
Is this one sudden case in an otherwise healthy pen?
Are the calves immediately around it beginning to follow?
Or, as I was seeing, are calves in several separate pens changing at the same time after experiencing the same disruption?
Patterns do not give us a guaranteed diagnosis. A common infectious source can also reach several pens. But the pattern helps us weigh what is more likely.
Yesterday, mine remained bright and drinking. Several different pens that had experienced the same milk disruption were following the same course. Moving them would not fix the shared cause. It would simply create another change.
So I left them in their established groups.
I had corrected the feeding problem, marked the affected calves and kept watching them closely.
That did not mean I had decided there was no infectious risk. It meant that, with the information I had at that moment, maintaining familiarity and consistent feeding seemed more helpful than moving them.
My threshold for changing that decision remained low.
A calf is coming out if it becomes dull, cold, weak, dehydrated or reluctant to drink. It is coming out if it loses its suck, cannot compete at the feeder, needs tubing or requires repeated individual care.
I would also be much quicker to remove one sudden, profusely scouring calf from a previously unaffected pen, especially if there were blood, fever, rapid spread or another reason to suspect an infectious outbreak.
On the other hand, I may leave a calf where it is, with close monitoring, if it remains bright, warm, hydrated and drinking, particularly when calves in several pens are responding to the same known disruption and the available sick bay would create a significant environmental change.
Leaving it does not mean doing nothing.
It means marking it, checking its temperature and hydration, watching its intake and behaviour, keeping the bedding dry and knowing exactly what change would make me move it.
It also means treating the pen as potentially exposed, not adding younger calves and being careful about carrying contamination on boots and equipment.
The official biosecurity answer is to isolate scouring calves, and the infectious-disease science behind that advice is strong.
But on farm we also have to consider the individual calf, what caused the scour, the pattern across the shed and what our isolation facilities actually offer.
Sometimes removing the calf is clearly the right decision.
Sometimes leaving it in the environment where it is warm, drinking and coping may be the better of two imperfect options.
And sometimes, as it was for me yesterday, there is no beautifully obvious right answer.
There is only the information in front of me, the risks on both sides, and the responsibility of choosing which risk I believe is greater.
Those decisions weigh heavily because I know being wrong in either direction can have consequences.
So I make the best decision I can for the calf in front of me, even if it isn’t text book perfect, keep watching, and stay willing to change my mind when the calf gives me new information.
Picture of an unaffected calf in one of the affected pens, seems breakfast in bed was on the menu.