To measure is to know and therefore you will not be a successful farmer if you don’t weigh your cattle on a regular basis. This is the fifth part in our beef cattle handling series and this month we look at scales and the importance of weight record keeping. We thank the ARC-Institute for Agricultural Engineering in South Africa who made their manual on handling facilities available to ProAgri Zambia so that our readers can benefit from their research and knowledge.

Sufficient, accurate knowledge is the first prerequisite for effective decision-making. This also holds true for cattle husbandry, may it be stud farming or beef production. Regular weighing of cattle is necessary to tell the farmer whether he is still on the right track and to warn him in time to make rectifications if needed.

Great demands are placed on scale operators, and psychological and physical exhaustion give rise to inaccurate results, rough handling of the animals and mistakes on the information gained. Special attention must therefore be given to the choice and placement of a scale to ensure easy and effective handling of animals.

There are basically four categories of scales, namely:

• Spring balance scale
• Hydraulic scale
• Oil bath scale
• Electronic scale

Position of the scale in the handling complex

Depending on the specific set-up, a scale can be placed in the working area. This is the cheapest option, as an additional passage is not required for weighing. Ensure that the scale has a locking mechanism, to prevent the scale from being subjected to unnecessary shock loads when cattle move over it for other purposes.

General suggestions for the placing of a scale:

• Ensure that sufficient shade is pro-vided for the scale operator.
• Ensure that the scale is placed on a hard, level (preferably a concrete slab) surface. This will prevent inaccurate readings.
• Place the scale in such a way that animals that have been weighed can move to either the loading platform or the holding pen.

Access gates

Access to the scale can be controlled in different ways:

• Access gate that swings outwards:

The disadvantage of this gate is that it is opened into the face of the approaching animal. To prevent this, animals can be held back in the crush with the aid of a crossbeam. If the animals are used to this type of access gate, they will leave sufficient space for the gate to open.

• Trapdoor

This type of gate does not take up much space, but the operation of the gate can be an exhausting exercise because it has to be lifted with a rope. A counter mass can however be affixed to the gate to make it easier to operate.

• Pipe:

Instead of using an access gate, a pipe can be affixed in the crate at a point which can be adapted to the size of the animal. This pipe is held in position with hooks in the side beams.

The choice of control at the entrance depends largely on the conditions on the farm.

Body clamps and crates

Some crates are provided with swinging body clamps that serve two purposes:

• To adapt the width of the crate when calves or smaller animals are handled.
• To keep an anxious, unwilling animal tightly against the side of the crate so that the mass can be determined accurately.

These body clamps work satisfactorily if the locking mechanism is designed in such a way that accidental unlocking is prevented. The body clamp must also run the entire length of the crate to prevent calves from landing up on the wrong side of the clamp.

Exit gates

There are mainly two types, namely:

• Open-beam type exit gate

It enables the animal to see past the beams and be reassured it that it will not enter an enclosed space. The gate swings open to the outside.

• Gate with neck clamp

This type of gate, combined with a neck clamp to a scale, can also be used for veterinary purposes. The neck clamp must be designed to control animals safely, and it must be provided with an easy releasing mechanism. It is essential that the mass measuring mechanism of the scale should be disconnected when the steel crate is used for dosing, branding or dehorning.

Crate floors

Most scale crates have hard wooden floors. Cross bars on the floors prevent animals from slipping and getting injured. The bars must remain firmly in position at all times.

Some scales have floors made of thick steel. These are durable and are also fitted with cross bars. The farmer must examine the bars beforehand for sharp edges.  Anxious animals that stamp about on the steel floors often create a noise that may upset all animals. A thin layer of sawdust can be strewn on the floor to prevent this. Slippery floors must be prevented at all times.

If manure or urine collects on the scale, it must continuously be removed during the weighing action. It can be swept away, flushed away or covered with sand. Ensure that the scale is “zeroed” before each mass reading.

High, solid sides (approximately 450 mm high) on a scale will prevent animals from stepping sideways and hurting themselves. High walls will also make it easier to weigh calves.

Installation of a scale

It is essential that the scale is calibrated at regular intervals. Scales must then be tested with masses of the same size as the average animal to be handled. Bags of cement, fertiliser or grain can be used for this purpose, if their masses have been determined on an accurate platform scale.

Re-calibration can be done as follows:

• Set the system on nil.
• Place the mass on the platform and get the correct reading.
• Remove all dirt from the platform and make the necessary adjustments.

Maintenance

The general requirements must be adhered to in order to ensure maximum performance from a scale for as long as possible:

• The scale must be kept clean to prevent a build-up of dirt and manure, as this can influence the performance of the parts.
• The authenticity of the readings must be examined regularly for re-calibration.
• Use the correct type of oil in the dashpot.
• The spring balance and reading column must be removed after weighing.
• The spring balance must be mounted carefully so that the parts can move freely.
• The wooden floor and scantlings must be examined regularly to ensure that there are no breaks or cracks.
• In the case of an oil bath scale, the oil level in the container must be checked regularly.
• Bearings and hydraulic pressure cells (where applicable) must be examined regularly.
• Ensure that a lightning deflector is coupled to the scale.
• Make provision for wheels on the scale to make it portable (if applicable).
• New-born calves can be weighed with a simple, cheap suspended scale, as shown in figure 1.

Next month we shall look at loading platforms, tilting tables, hoof-lifting crates and dipping facilities.

Published with acknowledgement to the ARC-Institute for Agricultural Engineering for the use of their Beef Cattle Handling Manual. Visit www.arc.agric.za for more information.