Clearly defined pens for every purpose or operation makes farming so much easier and enjoyable. But keep in mind that animals staying in an enclosed area offer many challenges. It is sensible to place your animal pens downwind and in such a position in relation to the housing and feed processing area that odours and problems with run-off will be limited.
We thank the ARC Institute for Agricultural Engineering in South Africa for making their manual on sheep production and facilities available to the readers of ProAgri Zambia.
After offloading incoming sheep, they have to be inoculated against pulpy kidney, dosed for internal parasites and vitamins A, D and E must be administered. The sheep are weighed, dipped and kept in adapting pens for five days. The purpose of the adapting pens is to gradually make the sheep used to the ration provided in the feeding complex. Sudden exposure to new feed can lead to acidity that may cause sheep to die. Depending on the size of the group, sheep must be sorted on arrival or
after the adaptation period. Sheep with wool older than six months are sheared before being allowed into the feeding complex.
Holding pens (receiving and dispatch pens)
The area provided in front of the loading ramp is used for keeping the sheep in groups for dispatch. In the case of incoming animals, the sheep are gathered there before any treatment is given. The typical space requirement in the holding pens is 0,5 m² per sheep.
Gathering pens and crowding pens
Gathering pens are pens through which sheep pass in small groups to further activities. Gathering pens usually hold 25 sheep for easy handling and a surface of 0,5 m²/ewe or 0,7 m²/ ewe with lamb should be provided. The gathering pen is usually round or funnel-shaped and examples are shown
in figures 1, 2 and 3. The sides of the round gathering pens are usually solid and typical building materials include brickwork, concrete, wood, sheet metal or rubber tyres.
Sheep are collected in post-gathering pens after treatment, before they are moved back to the feeding complex in a group. An area of 0,5 m²/sheep for the post-gathering pen must be provided, usually towards the crush. In lay-outs where sorting pens are placed after the crush, it is not necessary to have post-gathering pens, because the sorting pens can be used for this purpose.
Sorting pens and sorting gates
Sorting pens and sorting gates are used to separate certain sheep from others in the production process. The sorting pen will therefore be used to sort new animals, to separate lambs from ewes or to separate sheep to be sold from the rest. Sorting is done from the crush and usually to the scales with the aid of a number of gates controlling access to specific camps. Figures 4 and 5 show a
typical configuration for the sorting of sheep in two, three or four camps. Sorting pens are used for relatively short periods after which the sheep move back to the feeding pens. The area must, as is the case with gathering pens, provide 0,5 m²/per ewe.
Crushes or working alleys
Crushes are used to classify certain types of animals and to work on sheep or for the treatment of diseases. In the handling facility, distinction is made between crushes, alleys narrower than 600 mm and wider alleys (approximately 1 000 mm), also known as working alleys.
a. Working alleys
Some farmers prefer to be amongst the sheep while working with them. It is also necessary to separate treated sheep from untreated sheep during treatments such as castration and docking. For these actions, the wider, shorter working alley as shown in Figure 6 is preferred. The sides are 1 m
high to keep sheep inside while enabling the handler to climb in and out of the working alley with ease. The working alley is approximately 1 m wide, 6 m long and allows for ± 10 to 15 ewes. In the configuration, the handler can treat the sheep without them passing by him. Treated sheep are let through and are thus separated from the untreated sheep. Vertical sliding gates allow the handler to lift the gates by means of ropes to let sheep in or out.
Two adjacent working alleys can increase efficiency by filling one with sheep while the handler is busy in the other alley. This cuts out the time that the handler must wait for the next group. A portable working table as shown in Figure 7 can be used for individual treatment.
The sheep is caught out of the alley, turned over onto the table, treated and then pushed to the front of the working alley. Material and construction details for working alleys are the same as for those of normal crushes.
For farmers who prefer to work with the sheep from the side, there is a smaller crush which is perfect for treatments such as dosing and injections. The aim of the crush is to get a single row of sheep with their heads in the same direction. Sheep should not be able to turn in the crush. The crush must have smooth solid sides, so that the sheep can only see the opening and sheep in front of them.
Sheet metal or old tyres can be used, or even a brick wall. An opening must be left on the front through which work can be done on a sheep if necessary. A crush width of 375 to 550 mm is recommended, depending on the breed. Arched crushes or crushes in an “S” shape also give good sheep flow, since they cannot see the entrance in front of them and just keep on walking. Where V-shaped crushes are used, a base width of 200 to 300 mm and a top width of 450 to 675 mm is recommended. A gap of 75 to 100 mm between the floor and the sides provide space for the handler’s feet, allows drainage and hoof inspection and prevents young lambs from suffocating. The sides must preferably be a steel frame construction of square tubing or pipe.
Support poles must be planted firmly into the ground and the cross-poles must be bolted to these and welded. The walking surface can be earth or, at larger facilities, a rough concrete surface to prevent trampling. The surface must have a slight slope for runoff water. It is also preferred that crushes be placed under a roof, especially when working on sheep during rainy or very hot days.
Next month we shall look dipping facilities. Published with acknowledgement to the ARC Institute for Agricultural Engineering for the use of their Sheep Facilities Manual. Visit www.arc.agric.za for more information.