Thursday, 16 January 2014

Weighing goats: A dressmaker's tape and arithmetic.

Its just over a year since I weighed the goats so it time to do it again. They will need dosing for worms and in order to know how much to give them I need their weights. I explained how this is done without weigh scales ( they are very expensive) in November 2012, "How to weigh a goat with a piece of string". I have moved on since then and bought a dressmakers measuring tape in the village shop.

Pia's vital statistics
This method can be applied to cattle, goats, sheep and pigs. Goats are the easiest because they will stand still and are not too big. So first secure your goat in a head yoke or get a friend to hold it still on a halter. Pass the tape around the abdomen just behind the shoulder blade and over the fore ribs, this is the "heart girth". Then measure from the pin bone to the point of the shoulder. All of these measurements are in inches!

The maths next; multiply the girth squared by the body length and divide by three hundred. This gives you the weight in pounds because the formula was designed for Americans. In Europe and the rest of the World divide the pounds by 2.2 to get the answer in kilograms.

You can now work out how much wormer your goat needs. However, most wormers are licensed for use in sheep not goats. the market for goat medicines is so small that the pharmaceutical companies don't test for goats and use is, "off label" on veterinary advice.

Because food passes through the gut twice as fast in goats as in sheep you need to give double the sheep dose per kg, body-weight for the medicine to be effective.

Their weights as calculated by the above method are; Pia 71kgs, Acorn 68kgs and little Hebe 53kgs.

If you don't give the correct dose there is a risk that you will encourage resistance to the wormer in the worms. Too much is wasteful and potentially dangerous.

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