It is important to know the accurate weight of your animal to administer drugs as well as predict feeding requirements. The most reliable information about the weight of an animal is obtained by the use of a weighing scale. A good weighing scale for cattle will cost you about Sh210,000, which is out of reach for most small-scale farmers. Fortunately for the purposes of drug administration, the body weight of an animal should be estimated accurately to within 20 per cent of their true weight.
This gives room for safe weight estimation.
Most seasoned animal health practitioners are able to estimate the weight by observation and using the known average by age of a given breed. The guide is as given in the table right.
However, the weight band is an alternative way of accurately estimating the body weight of an animal. It exploits the high correlation between the circumference of the chest and body weight. With the right amount of tension on the tape, one will get within 5 per cent of the real weight. Commercially available bands have the weights printed on them.
In the absence of a weight band, an ordinary 3 metres tape measure is used.
This tape gives the circumference measurements in centimetres which are then converted to kilogramme using a conversion table.
135cm = 214kg
182cm = 500kg
When taking measurements, the band/tape is placed just behind the front legs under the body behind the elbow and all the way around to the point behind the shoulder blade.
It is important to note that the information acquired using these two methods is less accurate than the one obtained by the weighing.
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