Viabilty of week old poo sample for egg count

chrissie1

chrissie1

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I took a sample from a stable last Wednesday morning, so passed overnight 22nd/23rd March, and sent it off 1st class right away to a well known company. I needed to know the result fairly quickly so rang after lunch today, and the chap I spoke to asked the details and 'hummed and haa'd' a bit and said he'd call me back.

He rang and said that as it so happened they were looking at this sample as I rang. Of course that may well be the sheerest coincidence or maybe they hadn't actually examined it until my call? But either way that sample is all but a week old by now.

Question is this - given that from the horse passing it, me posting it, and them receiving it has to be at least 36 hours, even if they chill the samples on arrival is this result going to be anything like accurate? I asked our vets reception staff about doing a count recently and they were very against me posting it saying that the time in the post at room temperature allowed eggs to hatch out, and that people literally drove to them and handed them over fresh. She also said that chilling the sample to be looked at another day didn't work either. I appreciate that she was not a Lab. technician so may not have that quite right.

But this experience today has raised the question in my mind as to how accurate the egg counts can be since they are always more than a few hours old by the time they get to a processing company.
 
If it had been a nice warm balmy 25 degree C plus they might start to hatch out in 48 hours. However with our current temperature and refrigeration (which does stop development so you can easily refrigerate overnight - they don't have to come steaming hot direct from horse to lab) it should be OK. You just need to check with the lab when they actually received it.
 
Well, our vet does the egg-counts for us. She collects from us on her way to her clinic and does the count that day or the next.

I did ask her if I could get one from the field for the non-stabled pony and she replied that no, it does really need to be fresh.
 
Well,let's assume for the sake of argument that it was received as intended on the Thursday. Would refrigeration stop development from Thursday until the next Tuesday?

I find it interesting that JackyandRosie's vet is working on them pretty much as fresh as possible?
 
I did some tests on this earlier in the year. A wormy sample was tested each day, having been stored in a cool room but not refrigerated. The count was a medium one of about 600 epg and remained broadly similar each day until day 6. After that the count dropped away to <50 epg over a couple of days.

Generally samples remain viable for several days in my experience.
 
Not collecting it from the field is because free living nematodes move into the sample and lay eggs into it. If you follow the pony around the field and collect it as or very soon after its deposited it is certainly usable. In my experience refrigerating the sample soon after collection i.e. within 24/48 hours if not too high an ambient temperature maintains the egg count for months.
 
I actually posted a reply yesterday aafternoon, but see it hasn't appeared.

I accept what has been said, thank you and will therefore take the result on face value, but think that I will use either another company next time or since the vet will be here with routine stud work when she is due a retest, ask him to take it with him.
 
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