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Animals which are handled constantly, are normally very quiet and can be managed easily with very limited facilities. Larger herds with less individual handling of the animals and new management practices such as artificial insemination, castration, inoculation, dehorning and weighing will increase the need for handling yards. A simple handling yard will include a holding pen, a forcing pen, a race, a crush with a head restraint and a loading ramp. A more complete handling yard may also include drafting facilities and several holding pens for the sorted animals. A dipping tank or spray race can also be included. The size and complexity of the yard depends largely on the number of animals to be handled at any one time.
Handling facilities can be built of inexpensive materials, but should be of such standard that jobs are easily carried out. All fences in the handling yard should look strong and be strong and clearly visible to the animals to prevent bruising. Post and rail fences fit these needs best. Wire fences are suitable only for receiving yards where the animals are held prior to entering the main yard.
The handling yard should be situated centrally to the grazing paddocks in a village and must be on a site with good drainage. Shade and drinking water should be available. The site should also be accessible to lorries throughout the year.
The fences of the holding and forcing yards should be at least 1.65m high if large active zebu cattle are to be retained. Posts 150 to 200mm in diameter should be set at least 0.8m into the ground and spaced not more than 2.5m apart. Four 150mm or five 100mm rails are attached to the inside of the posts with slightly larger spacing at the top of the fence.
Table 13.2 Space Requirement for Holding and Forcing Pens
|Animal||Holding Yard||Forcing Yard|
|Category||m²/ Animal||m²/ Animal|
|> 550 kg||2.0||1.2|
|Ewes with Lambs||1.0|
Holding yards for sheep can have lower fences, but they need smaller rail spacing, especially if lambs are to be handled.
Figure 13.20 Simple cattle yard.
Figure 13.21 Alternative sections for cattle race.
Cattle Races and Crushes
Quick operations such as branding, spraying and giving injections only need a race to position the cattle. More specialised work such as ear marking, dehorning, castration, foot trimming, weighing, artificial insemination, pregnancy testing and veterinary operations requires a crush to firmly restrain an animal. The crush is best located as an extension of the race. Moving cattle into the race is often a slow process, but once a few animals have entered, others will readily follow. The race should therefore be long enough to hold three animals waiting to enter the crush or be at least 6m long. Post and rail fences of the same type as for the holding yard are used for the race, but the height should be increased to 1.8m. Where round timbers are used for rails, they should be arranged so that the thick end of the pole faces the front of the race to minimize the risk of animals injuring themselves on projecting butt-ends. The rails should be joined on posts for extra strength. It is important that the width of the race be correct so that animals can move easily but cannot turn around, i.e. 500 to 700mm between rails depending on the size of the cattle. Cattle with very large horns are a problem.
The only real answer is to build a race with sloping sides and reduce the height of the fence.
It is desirable for the entire length of the race and crush to be floored with concrete. A solid wall about 600mm high at the bottom of the fences will reduce the risk of leg injury if the cattle should slip. Such walls are especially necessary in races with sloping sides.
A simple crush need only consist of a head bail at the end of the race and a side opening gate in the last panel of the race. To improve access to the side of the animal, the gate can be split horizontally in halves so that the top half can be opened while the bottom half restrains the animal. It will also be advantageous to have a sliding gate or tail bar at the entrance of the crush to hold back animals and give easier access to the rear of the animal in the crush. The animals should not have to back up to leave the crush. This can be solved by having a side gate which opens at the front of the crush or the head bail constructed in a gate or a head bail constructed so that it can be opened wide enough for the animal to walk through. The head bail should fix the head of the animal with vertical bars since horizontal bars may cause choking of the animal should it collapse or slip. Dehorning however will require that the head be restrained both vertically and horizontally. In such cases a bar at the top and a chain in a quick release at the bottom will adequately hold the head.
Figure 1 3.22a Cattle crush.
Figure 13.22b Head bail.
Figure 13.22c Sliding gate.
A loading ramp is necessary to load stock into lorries for transport to market or transfer to other grazing areas. Figure 13.23 shows typical dimensions for a cattle loading ramp. Note that the ramp floor has cross battens every 20cm to prevent slipping. The catwalk along the outside is convenient for workers who are urging the animals along. A height of 1. 1 m is a little low for articulated lorries and a little high for most two-axle lorries. However, it should be adequate for either. A ramp slope of approximately 30cm/m is suggested.
Figure 13.23 Loading ramp.
A sorting alley will be useful in a handling yard where large herds must be drafted into several different groups on a frequent basis. A sorting alley is basically a race with side gates which can be swung into the race, thereby directing the animals into holding yards, one for each class of animals. The yards can be located on one or both sides of the race.
Auctioning of animals has the advantage of establishing the market price on animals of the same quality. This will encourage farmers to market better animals and buyers will get access to a central market instead of going around to many different farms (producers).
The auction system demands both good management and a well prepared sales yard. Figure 13.24a shows the principles of a sales yard for approximately 500 cattle and 350 sheep and goats. The yard is calculated for 40 cattle/ sheep in each pen or 1.3m²/cattle and 0.25m²/sheep or goat.
Cattle shall be registered and marked before sorted into size and sex. Each category will then be sold in groups or individually. Note that if sold one by one a maximum of 250-300 cattle can be sold during a day.
A monthly auction will create a widespread interest and buyers and sellers may come from a large area. Normally a market will establish itself near the auction area which should be considered when choosing the site.
The auction should start with the largest cattle first and taken in groups to the collecting point from where 12-15 cattle at a time walk into the auction ring. When sold the cattle shall go to respective buyers pen.
Because of the heavy wear and tear, maintenance has to be done regularly. Especially the gates are weak points.
Access to water in each pen is a necessity especially when dairy cattle are sold.
Figure 13.24a Sales yard.
Figure 13.24b Auction ring in sales yard.
de Veen J.J., The Rural Access Roads Programme, Geneva, International Labour Organization, 1980.
Hindson J., (rev. Howe J., Hathway G.), Earth Roads, Their Construction and Maintenance, London, Intermediate Technology Ltd., 1983.
Longland F., (ea. Stern P.), Field Engineering, An Introduction to Development Work and Construction in Rural Areas, London, Intermediate Technology Ltd., 1983.
Ker A.D.R., et al., Agriculture in East Africa, London, Edward Arnold Ltd., 1979.
Leighton J., Guide to Fencing, Supplement to the New Zealand Farmer, April 27, 1978.
Midwest Plan Service, Beef Housing and Equipment Handbook, Ames, Iowa, Midwest Plan Service, 1975.
Pattison R.J., Cattle Handling Facilities, FAO Informal Technical Report No. 27 UNDP/FAO/ETH 72 006, 1974.
Water, along with food, is one of the essentials of life. Perhaps because of its importance and scarcity in many locations the use of water is encompassed with very strong cultural/social precepts in most societies. Hence the success of projects aiming at improved water supply and quality must be performed with the full participation of the village population, in particular the women as they are the main users of water. While relatively small quantities will sustain human life, much more is needed for cooking, personal hygiene, laundry and cleaning. Water for a sanitary system is desirable but not essential if it is scarce. Water is also required for livestock and perhaps for irrigating crops.
Types of water for the farmstead: a Clean water for use in the home b Reasonably clean water for livestock c Water for irrigation
Quantity for Domestic Use
When determining the volume of clean water for domestic use, the location and convenience is a significant factor as shown in Table 14.1.
Table 14.1 Domestic Water Consumption per Person
The range of consumption given in Table 14.1 has a factor of over 100. It seems obvious that people adapt their needs to the supply. At the low extreme the bare minimum is used for cooking and drinking while at the other extreme water is used with abandon. Under conditions of shortage, much lower quality water may be used for personal hygiene and for washing clothes. The suggestions that follow will hopefully improve both the supply and the quality of water.
Quantity for Livestock
Table 14.2 gives the estimated water requirements for various classes of livestock. From this the total requirements can be determined.
Table 14.2 Water Requirements for Livestock
|Type and Number||Daily needs
|upgraded dairy cow.......||x 70 =||..............|
|upgraded beef cows ........||x 50 =||..............|
|local cattle .................||x 20 =||............|
|sheep .....................||x 5||............|
|goats.....................||x 3 =||............|
|poultry, dipping, biogas etc.........................||...............|
If water for dipping livestock is to be drawn from the same source, then 3 litres per head of livestock per week must be added to the estimated amount needed.
Fish can be raised in the reservoir without any additional volume of water. Chickens, pigeons and turkeys can live on used water from the house, but ducks and geese need about 1 litre of fresh water daily per bird.
For the production of biogas, a weekly consumption of about 100 litres must be included in the total requirement of water for livestock.
Quality of Water
Water from a protected well is nearly always free from harmful bacteria although it may contain dissolved salts that make it less than desirable for drinking. A protected well is located up grade from sources of pollution such as animal yards and privies. Twenty metres is an adequate distance in areas with fairly heavy type soils, while double that distance is necessary for light soils and even more in areas with limestone formations. "Protected" also implies a well head that extends high enough above the ground level to prevent anything from washing or blowing into the well mouth and narrow enough to discourage the users from standing on it. The other essential feature is a concrete apron sloping away from the well on all sides. A sanitary means of lifting the water is also necessary.
Water from roof catchments is generally safe for drinking and other domestic purposes. The dust and bird droppings that accumulate on the roof during dry times are usually carried away at the start of the first rain and should be diverted away from the storage tank. A paved catchment to collect water for domestic use must be fenced to restrict animals and people. It should also be allowed to clean itself before the water is saved. Water that is stored for a week or more in a catchment tank will generally be free of any harmful bacteria such as those causing cholera, typhoid and diarrhea in children as these bacteria cannot live for long outside the human body.
Streams and ponds, whether artificial or natural, are very likely to be contaminated and should be used for domestic purposes only as a last resort.
When the only water available is turbid (cloudy) and suspected of being polluted, it should be filtered through a well-designed sand filter. Even then, the safety of the water for drinking is questionable and boiling or other purification is recommended for complete safety.
Long term storage of drinking water does not give rise to problems as long as the tank is always properly cleaned before the start of the rains, and the top of the tank is covered with fine wire mesh (mosquito nets), to prevent small animals from crowing in the tank.
The use of chemicals, cooking or biological treatment of the water might be necessary, in order that good quality drinking water is obtained.
The success of rain catchment depends on two things:
The type of surface determines both the quality and quantity of water saved.
The catchment area can be divided into:
Total run-off areas such as a hard roof surface or a protected paved area which allows the catching of nearly all the rain that falls on it. If surface dust and impurities are flushed away first, the water collected should be good for domestic use.
Partial run-off areas are hard surfaces such as rocky outcroppings, roads, and compounds which allow the catching of up to half the rain falling on the area. The water obviously will not be as clean, but if stored properly should be satisfactory for livestock requirements.
Other surfaces, even though the soil may be quite loose or covered with vegetation, may have considerable run-off during hard rains. Water from these sources is likely to carry a considerable amount of sediment into the storage, making the water suitable only for crop irrigation.
If wells are dug close to surface water storages they can provide high quality water.
The advantage of roof catchment systems is that even light rain showers will supply clean water and the total run-off is easily stored in a tank situated next to the house.
Types of Storage for Roof Catchments
Granary Basket Tank (UNICEF design) is type of tank uses a granary basket of woven sticks as a built-in framework for a cement-mortar plastered tank. The cost of the framework is only the labor of cutting and weaving sticks into an open-weave basket.
To improve strength and allow the construction of larger tanks, the outside of the basket can be covered with a layer of chicken wire after which barbed wire is wrapped with a 150mm spacing before the basket is plastered inside and out. A rich mortar of about 1:3 portand cement to sand should be used and mixed with just enough water to make the plaster easy to apply.
Without wire reinforcement the tank size should not exceed a diameter of 1.5m and a depth of 2m. If it is reinforced with barbed wire it should not exceed a diameter of 2.5m and a depth of 2m. A cover is desirable and can be made of mortar reinforced with chicken wire.
Figure 14.1 Reinforced mortar tank (Courtesy of Erik Nissen-Petersen).
Large cement jar is tank is a large bag with framework made of cloth or sacks and stuffed with sawdust, sand or rice hulls. Mortar is then plastered on to the bag, chicken wire and barbed wire are tied on to the plaster and another layer of plaster applied. The bag is removed from the inside of the jar after 24 hours, and plaster is applied to the inside to make it waterproof. The bag can be used for many water jars making the cost per tank minimal. A 1:3 portland cement to sand mortar is essential. The same size restrictions apply as for the granary basket tank. In both this tank and the granary basket tank the curved sides contribute to the strength and life of the tank. A cover is desirable.
Concrete ring tank sections can be used to form water tanks of about 2,000 litres capacity. The small tank volumes are suitable for rain catchment from small roofs scattered on a compound and for areas with relatively even annual distribution of rainfall. A reinforced concrete cover should be installed. These tanks are particularly suitable where a form can be obtained for community use. With the casting done on site, expensive transportation is avoided.
Figure 14.2 Concrete ring tank (Courtesy of Erik NissenPetersen).
Concrete block tank must have steel reinforcing incorporated into the walls. Two barbed wires laid completely around the tank and imbedded in the mortar between each course of blocks is adequate. The blocks must be of good quality to be relatively impermeable and keep leakage and evaporation to a minimum.
The site for a tank of this size must be on firm ground with a reinforced concrete base. If the original ground is sloping, it is necessary to dig out the high area but not fill in the low side.
Corrugated galvanised steel tank is the quickest and easiest way of providing a roof catchment storage is to buy and install a corrugated steel tank. The steel sheets are rather easily damaged, but if they are handled carefully and protected from corrosion by coating both the inside and outside with bitumen and then installed on a concrete base, they make a very good storage.
Table 14.3 Storage Tank Selection and Sizes
|Type||Range of capacity (litres)||Relative cost||Notes|
|Waterjar||< 1,000||Low||No reinforcement needed, filled sack used as form|
|Waterjar||< 5,000||Low||Reinforced, sack form|
|Granary basket tank||< 10,000||Low||Woven stick form, reinforced with chickenwire and barbed wire|
|Precaste||2-3,000||Med||Simple to install|
|Concrete rings||Less expensive if cast at site|
|Concrete block||< 20,000||Med||Requires good base and reinforcing|
|> 1,000||High||Simple to build, needs good base and corrosion protection.|
Figure 14.3 Roof catchment (Courtesy of Erik NissenPetersen).
Partial Run-off Catchments
In areas with heavy rainfall during relatively short periods the run-off can be considerably high if the ground level catchment areas are well sloped and hard surfaced, as much as 3/4 of the annual rainfall may be collected, but where there is little slope and a permeable surface, only about 1/4 can be saved. To compensate for a gentle slope, a soft surface, or the need for additional water, the catchment area can be extended or covered with a hard surface material.
For a small group of farmers a compound catchment tank can be enough, while for communal use, dammed reservoirs are more suitable.
If a dependable, continuous source of water is available, no storage facilities are required. However, with an intermittent supply, storage is essential! The theoretical size of the storage required is determined by multiplying the total daily needs, such as the family, livestock and irrigation, by the number of days expected to be without rain. However, it is the amount of water that is available for storage that is likely to be the limiting factor. Water used during the accumulation period must be subtracted from the total.
Figure 4.4 illustrates a method for determining the maximum storage capacity possible using the following procedure:
Figure 14.4 Estimating storage tank size.
Calculation of Tank and Reservoir Volumes
Roof Catchment Tank
One of the strongest and least expensive tank shapes for a roof catchment is cylindrical with a diameter greater than its height. The height is usually determined by the distance between the surface of the tank foundation and the lowest point of the gutters.
The formula for calculating the volume of a cylindrical tank using inside dimensions is as follows:
V = p x r2 x h x 1000 where:
V = volume, l
r = radius, m
h = height, m
V=3.14 x 2.252 x 2.0 x 1000=31,800l
Figure 14.5 Capacity of a cylindrical tank.
Table 14.4 Cylindrical Tank Capacities in 1,000 Iitres (Inside dimensions)
Catchment Tank for the Compound
Where a storage tank must be dug into a relatively level area of ground, an approximate half-sphere shape is easiest. The volume of a half sphere can be found by using its radius in the following formula:
V= 2/3 x p x r3 x 1000 where:
V = volume, 1
r = radius of half sphere, m
V=2/3 x p x 2.133 x 1000
V = 20,250 l
Water that drains from the compound or a large area may be stored in a pond or reservoir behind a dam. Estimating the water behind a dam is difficult because of the uneven topography below the water level. Two formulas that will help to make a rough estimate are as follows:
Figure 14.6 Half sphere tank.
For a long narrow pond, perhaps a dammed-up stream:
V=(1 x w x d/8) x 1000 where:
V = Volume, l
I = length of pond, m
w = width of pond at dam, m
d = depth of pond at dam, m
For a circular shaped pond that has an area in the middle that is quite uniform in depth, the volume is determined in two steps and the results are combined.
V1 = p x r2 x d where:
V1 = volume in uniform depth area, m³
r = radius of the area of uniform depth, m
d = depth of the uniform area, m
V2 = 1/2 x w x d x c where:
V2 = volume of sloping edges of pond, m³
w = width of sloping edges, m
d = depth, m
c = circumference or length of sloping edge, m
(3 x the diameter is a good approximation)
Vt = (V1 + V2) x 1,000 where:
Vt = total volume, I
Figure 14.7 Volume in a circular reservoir.
Assume a pond that is roughly 26m in diameter with a uniform depth of 2m in the center, an area estimated to have a radius of 10m. The approximate volume can be found using the previously described method.
V1= p x 10 x 10 x 2 = 629m³
V2= 1/2 x 3 x 2 x 70=210m³
Vt = (629 + 210) x 1,000 = 839,000 l
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