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B.D.H. van NIEKERK P. W. LABUSCAGNE and S. P. J. ELLIS Agricultural Research Institute Middelburg, C.P.


THE construction and uses of a type of self-feeder for sheep, which was developed at Grootfontein College of Agriculture, have already been described in Farming in South Africa (November 1958 and January 1960). This feeder was used extensively in various experiments with sheep and lambs and some minor modifications have since been made in the design.

A detailed description of the re-designed feeder unit, as well as the layout of a large-scale feedlot, is discussed below.



The construction of the basic 8-feet feeder unit is illustrated in Sketch 1. Most of the dimensions given in the sketch must be followed strictly. If they are indiscriminately changed the feeder will not operate efficiently.



The length of the feeder unit may vary, but should preferably not exceed 10 feet. If it is longer than that, the pressure of the feed causes the feeder and the adjustable frame to bulge outwards. This in turn reduces the six-inch gap between the inside edge of the crib and the adjustable frame and impairs the normal flow of feed into the crib. With the necessary support every eight to ten feet, however, the feeder can be extended to any length.

Prevent the animals from contaminating the feed with manure by fixing a beam (or any other suitable obstruction such as a length of piping) nine inches above the edge of the crib. This not only prevents the animals from treading inside the crib, but also reduces feed wastage caused by certain animals, which develop the habit of scraping feed out of the crib with their front feet.



One of the most important features of this feeder is the adjustable frame, which makes it possible to regulate the level of feed in the crib.

With these frames any ration may be fed with the minimum of feed wastage. When lucerne meal which has been milled through the ¼-inch sieve of a hammer-mill is fed, the lower edge of the frame must be set about level with the edge of the crib. With coarsely ground lucerne (1½-inch sieve) the lower edge of the frame must be above the level of the crib. For a mixture of maize meal and lucerne meal (¼-inch sieve), the frame must be lowered so that its lower edge is approximately half an inch below the level of the crib. If milled straw (which is unpalatable and flows readily) is added, the lower edge of the frame must be set still lower, about 2 inches below the level of the crib.

However, we can set down no hard and fast rules; only trial and error will give the correct setting for any given feed. The frame must always be set low enough to prevent feed wastage but not so low that the feeder becomes clogged.

If the frames are properly adjusted, the feeder will feed automatically and limit feed wastage to a minimum. Always re-adjust the feeder after any change in ration composition. The feeder is very sensitive and an adjustment of half an inch may make the difference between no feed wastage and considerable feed wastage.



The feeder unit can hold about 112 cubic feet of feed, depending on the type and physical composition of the feed. It will for example contain approximately 1250 to 1300 lb of coarsely ground lucerne (1½-inch sieve) or at least 2000 lb of a 60 percent lucerne meal and 40 per cent maize meal mixture (¼-inch sieve).



The amount of feeder space occupied by an animal will naturally depend on the size of the animal. A mature sheep needs at least one foot of crib space. Lambs occupy considerably less room because they are smaller and less aggressive.

Sheep have been observed to spend only about 20 percent of their time actively feeding at the self-feeders. Unfortunately, this feeding period is not evenly distributed over 24 hours, so that the feeding space can accommodate somewhat less than five sheep per unit of feeder space. If we assume that approximately four sheep can be fed per unit of feeder space, then an 8-feet feeder unit should be able to accommodate 64 sheep, provided that the animals are given free access to the feed at all times. Ewes with Iambs at foot need more room since the Iambs start feeding within the first 10 days after birth.



Construction costs will depend on the type of material used. With second-hand material sand creosote-treated poles, such a feeder unit would cost about R50 - a capital investment of less than R1 per sheep.



Self-feeders for large numbers of sheep can be constructed by combining various feeder units in almost any possible combination. The best design would be the one which makes the most efficient use of labour and equipment. There are probably many possible designs which will comply with these requirements.

Sketch 2 illustrates a self-feeder system consisting of a feed shed, feeding paddocks and self-feeders built in a semi-circle around a centrally located hammermill. The hammer-mill grinds the feed and blows it directly from the feed shed into the storage space above each feeder unit (or series of feeder units). Fences separate the feeder units from one another so that the animals can be fed in adjacent self-feeders.



This design has several advantages. The feed can be milled directly from the feed shed into the self-feeders. This eliminates unnecessary handling of the feed and having to move the hammermill from feeder to feeder.

This feeding system can also be readily adapted to feed large numbers of sheep with a minimum of labour. All you have to do is to increase the distance (R) between the feeders and the hammer-mill or to couple two or three feeder units in a row (L). The feedlot dimensions for various numbers of sheep up to 2850 are given in Sketch 2. The storage space above the feeder units makes it possible to grind and store enough feed for large numbers of sheep over a long period.

Sketch 3 illustrates an alternative feedlot design. This system consists of a feed shed, feeding paddocks and several rows of feeder units. The feedlot serving these feeder units can be so partitioned that different rations can be fed in each series of feeder units.



Feed can be blown directly into the storage space by means of a centrally located hammer-mill fitted with an extendible blowpipe. The number of rows of feeder units which can be served in this way will depend on how far the hammer-mill can blow the milled feed. If a large number of feeders are served, the hammer-mill will have to be mounted on a trailer so that it can be put wherever necessary. An alternative procedure would be to blow the feed into a bin located at one end of the row of feeders and from there to transport the milled feed by means of an auger to any point within the feed loft.



Whatever design you decide upon, always take the following factors into consideration:

This additional paddock is also useful when ewes are to lamb at the self-feeders. Ewes which lamb in overcrowded small paddock sometimes have difficulty in identifying their lambs, especially in cases of twinning. When lambs are tagged, it is also easier then to identify the ewe, and lamb. Once the ewes have accepted their lambs and the lambs have been tagged, they may once again be kept in the smaller feeding paddocks.


Feeder for self-feeder unit

You will need the following materials for building a self-feeder unit:

About 12 square feet per sheep are adequate where sheep are being fattened in dry lot. The additional paddocks, which are used only during rainy weather or .while the ewes are lambing, can provide approximately 45 square feet per sheep.

There are especially two reasons for restricting the area of the feeding paddocks: when the paddocks are too big, plants start growing there and may become a source of internal parasite infestation; secondly, a better quality manure is obtained in smaller paddocks.



G. N. LOUW and P. W. LABUSCAGNE, (1958). Bold experiment may be of great value to sheep farmers, Fmg. S. Afr. 34(8), 10.12.

B. D. H. VAN NIEKERK and P. W. LABUSCAGNE, (1960). Portable self-feeder for sheep. Fmg. S.Afr., 35(10), 29.



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