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Counting worms
A gelding I bought last July came with a huge worm burden. Despite worming him as soon as I got him and three months later, in December his health fell apart.
I found he was anaemic, had mouth ulcers and a faecal egg count of 600/gm. He was wormed by the equine vets and had teeth done; five weeks later his FEC was 1100 red worms. His paddock mate’s egg count was zero. I treated him with Panicur for five days and then Genesis, and his egg count was zero after that.
My horse is nine. The vet told me he probably wasn’t wormed regularly enough around the age of two and I need to have him on a strict worming programme, with regular FECs. It costs me $45 to get this done from here. Can you tell me how I can do my own egg count? There seem to be lots of second-hand microscopes around for sale. Exactly what equipment do I need?
Lee Barraclough, via email
A : Faecal egg counts are easy to do once you have the equipment, and after a brief lesson on how to recognise a worm egg.
There are two common methods of doing a faecal egg count – the easiest gives an approximation of the worm burden, the other will give a more exact measurement in eggs per gram of faeces.
Method A: You need a microscope, two small 50 ml containers, a test tube, a small sieve, microscope slides and cover slips and a flotation solution.
This flotation solution can be any solution with a high specific gravity. This is easily made – you can use a concentrated solution of salt and water by mixing salt with an amount of water until no more salt will dissolve.
You then thoroughly mix a small amount of faeces (say about half a teaspoon) with approx 25ml of the flotation solution. Then sieve it into another container to remove most of the larger particles.
Pour it into the test tube, right to the top so that the meniscus of the fluid is just above the top. Then place a cover slip on top so it comes into contact with the fluid. Any eggs in this solution will slowly float to the top.
After about five minutes, remove the cover slip and place it on a microscope slide and examine it under the microscope. Any eggs in the mix will be included in the drop of fluid that will adhere to the cover slip. You will get a rough idea of the concentration of faecal eggs in the manure.
Method B: You need a set of scales capable of accurately measuring about 5g manure. You also need a McMaster slide, which is a special microscope slide which has two chambers which each contain a small but measured volume of fluid. They also have a grid pattern on them – this helps you count the number of eggs in a certain volume of fluid.
In this method you mix a small, measured amount of manure with a measured volume of the flotation solution. You then sieve the fluid and immediately take a small volume of fluid with an eye dropper and fill the McMaster slide. You then wait about five minutes for any eggs in the chambers on the slide to rise to the top. Then examine under the microscope and count the eggs.
With this method, because you know the weight of manure, the volume of original fluid and the amount of fluid in the McMaster slide you are able to work out the number eggs per gram of faeces.
Standing or lying?
I have been advised that it is preferable for a colt to be castrated in a standing position rather than lying down on the side or back.
It has been suggested to me that there can sometimes be damage done to the hip joint when anaesthetised and relaxed ligaments are manipulated into abnormal positions when castration is done while lying down.
Have you any opinions about this? Are there any veterinary surgeons in New Zealand who will carry out the operation in a standing position?
Castration, Auckland
A : Normally, when a horse is castrated lying down, the uppermost leg is held forward with a rope. There is never a lot of tension used with this rope and the leg is not placed in an abnormal position.
I am not aware of any horse that has been damaged in this way.
With a general anaesthetic there is possibly a very slight risk of injury when a horse goes down or gets up, but this risk is very small. It is safer now than it used to be, because the anaesthetic agents used now facilitate a very gentle collapse and a relaxed recovery up on to his feet again.
There are a lot of vets in New Zealand who are comfortable doing a standing castration. I do most of mine standing. It is only really the colts that have had very little handling, and those that are too small to comfortably “work underneath”, that I choose to do on the ground.
Nosebleed nasty
My horse had a nosebleed (from both nostrils) the other day while I was riding him in the forest. He hadn’t had a knock to the nose that I was aware of, and it didn’t seem to upset him. Can you please tell me if I need to get the vet to see him, or is it a one-off?
Bridget, West Auckland
A : While a nosebleed can be an indication of a serious problem, I would not be too concerned with a one-off minor bleed that is not accompanied by any other problem.
If it happens again, or if there is any other concern that may be associated, eg. a cough, poor performance, excess respiratory noise or a reluctance to work, then it would be best to have your vet investigate.
This would best be done with an endoscope, to try and determine the source of the blood. Only then, are you adequately able to assess the significance.
If this examination is done on the day of the bleed, it will be much easier for your vet.
