Milking Parlour

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On commercial farms where several cows are milked at the time, a milking parlour becomes a feasible investment. Several types of milking parlours are in use in dairy regions throughout the world. Figure 10.16 a, b, c and d, illustrate some of the most common types.

Any type of parlour should have a high quality concrete floor and metal railings for durability and ease of cleaning. Walls are not required, but if supplied they should at least be plastered masonry walls. The pit where the milker stands should have a floor level 900mm below that of the cattle stands for the most comfortable work position.

The number of stands is determined by the allowable milking time of the herd or time taken to the concentrate ration.

Abreast Parlour

The abreast parlour allows cows to enter and leave individually. The variation of this parlour shown here, in which the front of the stands can be opened so that the cows can proceed forward out of the parlour after milking has proved effective. The main drawback with the abreast parlour is the relatively long distance to walk between milking points, and cows obstructing the herdsman, since they share the same floor space.

The stands should be 1.0 to 1.1m wide when a bucket milking machine is used or when hand milking is practiced, while 0.7 to 0.8m is adequate when a pipeline milking system is installed. In both cases the width for the milker should be 0.6 to 0.8m. A two-level abreast parlour, in which the milker works at a lower level than the cows stand, is more difficult to construct and has no outstanding advantages over the single level type. The abreast parlour has been common in East Africa for herds of more than 40 cows, but its uses is decreasing and giving way to the double herringbone parlour.

Tandem Parlour

The tandem parlour also allows for individual care of the cows. It is used mostly for smaller commercial herds and in particular, for herds with high yielding cows. The main drawbacks with this type of parlour are its larger space requirement and more expensive construction when compared to other types of parlours; of similar capacity. The parlour capacity in terms of cows milked per hour and labour efficiency can compare to that of a small herringbone parlour.

Figure 10.15 Milking parlour for a medium size herd.

Walk-through Parlour

In walk-through or chute parlours cows enter and leave in batches. They have been used mainly for small herds. Their narrow width can be an advantage where a parlour is to be fitted in an existing building, but it is inferior to other types in most other respects, however, it is cheaper to construct than a tandem parlour.

Herringbone Parlour

The herringbone parlour layout results in a compact working area and allows feeders to be fixed to the side walls. Four stands on each side of the pit, as shown in Figure 10.16c, is the minimum size of this type for high labour efficiency. If the herd has fewer than 80 cows, then a double-three parlour will keep the investment lower with only a small drop in labour efficiency. The popularity of the herringbone parlour is mainly due to its simplicity and its high capacity measured in numbers of cows milked per man-hour. (A man-hour is the equivalent of one man working for one hour). However, the risk of cows kicking the herdsman is greater in this type than in parlours where the herdsman stands alongside the cow.

Double 6, 8, 10 and even 12 stand parlours are used for very large herds. These larger parlours allow more cows to be milked per hour, but because of the need for more workers and the increased waiting time to allow all cows on one side to finish before they are released, the output per man-hour is usually less.

Grain Feeders

It is advantageous to equip milking parlours with grain feeders which allow each cow to be fed in ratio to her production. Since cows are more likely to enter the parlour when they expect to be feds some labour will be saved. Manual distribution of the concentrates with a measuring scoop is recommended except in the largest herds. Semi automatic and automatic systems are expensive to install and require spare parts and mechanics for their maintenance and these may not be available when needed.

Figure 10.16a Abreast parlour.

Figure 10.16c Walk through parlour.

Figure 10.16b Tandem parlour.

Figure 10.16d Herring-bone parlour.

Collecting Yard

The cows are normally assembled in a collecting yard (holding area) before milking. This may be a portion of the yard that is temporarily fenced off with chains. The collecting yard should have a minimum size of 1.1 to 2.0m² per cow. Large horned cows and a low herd number will require the largest space per cow. Provision must be made for water for the cows awaiting their turn to enter the parlour. The area should slope away from the parlour 20 to 100mm/m. This not only improves drainage, but also encourages the cows to face the entrance.

The collecting yard should be paved for easy cleaning and to allow for sanitary conditions in the parlour. A roof is desirable for shade and to avoid wet cows entering the parlour in the rainy season and it will reduce the amount of rainwater that has to be stored in the manure pit.

Entrance and Exit

An entrance into the parlour that is straight (no turns) will ensure a smooth and convenient operation. Once trained, cows and heifers will walk readily into the parlour. A single step of about 100mm will help to keep manure from being carried into the parlour.

An exit leading into an uncrowded area will facilitate animal flow. A straight exit is desirable but not as important as a straight entry. If exiting alleys are needed they should be narrow (700 to 900mm depending on cow size), to keep the cows from turning around.

Feeding Equipment

One advantage of loose housing of cattle is the opportunity to construct the feed trough in the fence allowing easy access for filling. The simplest type of manger consists of a low barrier with a rail fixed above. However, cattle have a tendency to throw feed forwards while eating, but a wall in front, as shown in Figure 10.18, will reduce this problem. The dimensions of the trough must be chosen to conform with the height, reach and required width of the feeding space for the animals to be fed, while providing enough volume for the amount of feed distributed at each feeding time. Figures 10.17, 10.18 and 10.19.

Although timber construction is simple to install, concrete should be considered because of its greater durability. When timber is used, the base should be well treated with wood preservative. However, the preservative should not be used on any surface which cattle can reach to lick as some preservative materials are toxic to animals. When concrete is used, it should be at least C20, or a nominal mix of 1:2:4; since a lower grade concrete would soon deteriorate due to chemical attack by feed stuffs and the cow's saliva. The cows will press against the barrier before and during the feeding so that the head rail must be firmly fixed to the vertical posts, which are immovably set in the ground.

A 2.5m wide concrete apron along the feed trough will reduce the accumulation of mud. A narrow step next to the trough will help to keep the trough free of manure as animals will not back up on to such a step. The bottom of the feed trough should be at a level 100 to 400mm above the level at which the cow is standing with her front feet.

A slightly more elaborate feed trough separates the cattle by vertical rails or tomb stone barriers, as shown in Figure 10.19, to reduce competition during eating. The tombstone barrier may also reduce fodder spillage because the cow has to lift her head before withdrawing it from the trough.

A simple roof constructed over the feed trough and the area where the cows stand to eat will serve as a shade and encourage daytime feeding in bright weather while serving to protect the feed from water damage in rainy periods.

Watering Equipment

Drinking water for cattle must be clean. Impurities may disturb the microbiological activities in the rumen. Table 10.7 shows the requirement of drinking water, but a hot environment may considerably increase it. In dairy cows the need for water will increase with milk yield.

Figure 10.17 Dimension for feed trough design for cattle.

Figure 10.18a Perspective view of Timber Feed Trough.

Figure 10.18b Timber Trough.

Figure 10.18c Concrete Trough and a Step in front of the Trough.

Figure 10.18d Masonry Walls in the Trough.

Figure 10.19a Perspective view.

Figure 10.19b Section.

Figure 10.19c Alternative Design.

Table 10. 7 Drinking Water Requirement for Cattle

Water Troughs

The size of a water trough depends on whether the herd is taken for watering periodically or is given water on a continuous basis. If water is limited, the length of the trough should be such that all of the cows can drink at one time. A trough space of 60 to 70cm should be allowed for each cow. For free choice, the trough should be sized for 2 to 3 cows at a time. One trough should be provided for each 50 animals. Figure 10.20a and b shows a well designed trough made of concrete. The length may be increased if necessary. A float valve installed on the water supply pipe will control the level automatically. A minimum flow rate of 5 to 8 litres per minute for each cow drinking at one time is desirable. To prevent contamination of the water trough with manure, the trough should preferably have a 300 to 400mm wide step along the front. The animals will readily step up to drink, but will not back up onto the raised area. An alternative is to make the sides facing the cattle sloping as shown in Figure 10.20c.

Young stock held in a loose housing system require one water trough for each 50 to 60 animals. A 60cm height is satisfactory. A minimum flow rate of 4 to 5 litres per minute for each animal drinking at one time is desirable.

Figure 10.20 Concrete water trough.

Automatic Drinkers

Automatic drinkers which are activated by the animals provide a hygienic means of supplying water for cows and young stock. Figure 10.21. When used in loose housing systems for cows the bowl should be placed at a height of 100cm and be protected by a raised area beneath it. (1m² and 150 to 200mm heigh). One bowl should be provided for each 10 to 15 cows.

A nipple drinker without bowl provides the most hygienic means of watering for young stock, but most nipples have limited flow rate and can therefore not be used for calves older than 6 months.

Feed Handling

The types and quantities of feed stuffs to be handled varies greatly from farm to farm.

Figure 10.21 Automatic Drinker.

Dry Hay or Forage

If an adequate supply of green forage can be grown throughout the year, then only temporary forage storage and space for chopping is required. On the other hand if a prolonged dry season makes it necessary to conserve dry forage, a storage method that will prevent spoilage is essential. A raised slatted floor with a thatched or corrugated steel roof will provide good protection for hay. A simple storage similar to the sunshade shown in Figure 10.4 will be adequate.

If the store is filled gradually, it may help to have some poles in the top of the shed on which to spread hay for final drying before it is packed into the store. Loose hay weighs about 60 to 70 kg/m³. Although requirements will vary greatly a rough guide is 3 to 5 kg of hay or other forage per animal per day of storage.

Silage

Good quality silage is an excellent feed for cattle. However, it is not practical for the small holder with only a few cows because it is difficult to make small quantities of silage without excessive spoilage.

Successful silage making starts with the right crop. The entire maize plant including the grain is ideal as it has enough starch and sugar to ferment well. In contrast many grasses and legumes do not ferment well unless a preservative such as molasses is added as the forage is put into the silo.

It takes a good silo to make good silage. The walls must be smooth, air-tight and for a horizontal silo the walls should slope about 1:4 so that the silage packs tighter as it settles. The forage to be made into silage should be at about 30 to 50% moisture content and must be chopped finely and then packed tightly into the silo. The freshly placed material must be covered and sealed with a plastic sheet. Failure at any step along the way spells disaster.

The large commercial farmer, with well constructed horizontal or tower silos and the equipment to fill them, has the chance to make excellent feed. However, good management is no less important, regardless of size.

Concentrates and Grains

Again the amount to be stored is highly variable. The method of storing is little different from food grains and suitable storage facilities are discussed in Chapter 9.

Manure Handling

Careful waste management is needed:

• to utilize the fertilizing qualities of the manure, urine and other wastes;
• to maintain good animal health through sanitary facilities;
• to avoid pollution of air and water and to provide good hygiene around the farmstead.

The method of disposal depends on the type of wastes being handled. Solids can be stacked and spread on fields at the optimum time of year, while liquids must be collected in a tank and may be spread from tank-wagons.

Manure from a livestock production unit may contain not only faeces and urine, but also straw or other litter materials, spillage from feeding, and water. If silage is produced on the farm, the runoff from the silos should be led to the urine collection tank. Depending on the wilt the amount of effluent can vary from zero to 0.1 m³ or more per tonne of silage but normal storage allowance is 0.05 m³ per tonne.

Manure is handled as solid when the dry matter content exceeds 25%. In this condition the manure can be stacked up to a height of 1.5 to 2 metres. This condition of the manure is only obtained when urine is drained away immediately and a prescribed amount of litter, like straw or sawdust, is used. The use of 1 to 2.5 kg of litter per cow per day will ensure that the manure can be handled as a solid. Manure with less than 20% solids has the consistency of thick slurry. It must be collected in a tank or pit but is too thick to handle effectively with pumps. It must be diluted with water to less than 15% solids before it can be pumped with a conventional centrifugal pump. If diluted in order to use irrigation equipment for spreading liquid manure, the solids must be below 4%.

The amount of manure as well as the composition varies depending upon factors such as feeding, milk yield, animal weight, position in the lactation period, and health of the animal. Cattle fed on 'wet' silages or grass produce more urine. Table 10.8 shows the manure production in relation to the weight of the animals.

To estimate the volume of manure and bedding, add the volume of manure from Table 10.8 to half the volume of bedding used. Heavy rains requires removal of liquid for stacked manure, within the storage period. Similarly the storage capacity must be increased by about 50% or a roof should be built over the storage when slurry or liquid manure.

Example

Find suitable dimensions for a slurry manure pit with access ramp given the following:

Animals: 5 dairy cows 500 kg

Storage period: 30 days

Maximum slope of access ramp: 15%

Storage capacity (V) needed (see Table 10.8);

V = 5 x 30 x 0.055 = 8.25m³

Table 10.8 Manure Production in Cattle

* These values are for manure only - no bedding is including. Washing water used in the milking parlour may amount up to 300 litres/stall/milking. Usually 50 litres/head/day to allowed.

(Normal variation can be as much as ±20% of the tabled figures).

Assume the pit will be 0.5m deep and 5m long, see sketch

Total width (W) will then be:

W = V / (l₁ + 0 5l₂) h

I₂ = h / 0.15 = 0.5 / 0.15 = 3.3m

l₁= l - 1₂ = 5 - 3.3 = 1.7m

W = 8.25 / ( 1.7 x 0.5 x 3.3) x 0.5 = 4.9m

A pit 5 x 5 x 0.5m with a slope on the access ram of 15% is chosen.

Cattle Dips

Ticks continue to be one of the most harmful livestock pests in East Africa. As vectors of animal diseases ticks have been a great hindrance to livestock development especially in areas where breeds of cattle exotic to the environment have been introduced.

At present the only effective method of control for most of these diseases is control of the vector ticks. Dipping or spraying with an acaricide is the mose efficient way of reducing the number of ticks.

Siting a Dip

The ground where a dip is to be built, and the area around should be slightly sloping and as hard as possible, but not so rocky that a hole for the dip cannot be dug. Laterite (murram) soil is ideal: The ground must:

• support the structure of the dip;
• be well drained and not muddy in wet weather, and
• be resistant to erosion or gullying of cattle tracks.

Cattle must not be hot or thirsty when they are dipped, so it is important to have a water trough inside the collecting yard fence.

Figure 10.22 Manure pit with access ramp.

Waste Disposal and Pollution

All dipping tanks need to be cleaned out from time to time and disposed of the accumulated sediment. It is normal for all the waste dip-wash to be thrown into a 'waste pit' that is dug close to the dip. In addition dipping tanks may crack with leakage of acaricide as a result.

The siting of the dip and the waste pit must therefore ensure that there is no risk of acaricide getting into drinking water supplies, either by overflowing or by percolating through the ground. The waste pit should be at least 50 metres from any river or stream, 100 metres from a spring or well, and considerably more than that if the subsoil is sandy or porous. Figure 10.23 shows a typical site layout and describes the features in the order that the cattle come to them.

Footbaths

Footbaths are provided to wash mud off the feet of the cattle to help keep the dip clean. At least two are recommended, each 4.5 metres long and 25 to 30cm deep, but in muddy areas it is desirable to have more. Up to 30 metres total length may sometimes be required. Figure 10.23.

The floor of the baths should be studded with hard stones set into the concrete to provide grip, and to splay the hoofs apart to loosen any mud between them.

The footbaths should be arranged in a cascade, so that clean water added continuously at the end near the dip, overflows from each bath into the one before it, with an overflow outlet to the side near the collecting pen. Floor level outlet pipes from each bath can be opened for cleaning.

If water supply is extremely limited, footbath water can be collected in settling tanks and reused later.

Jumping Place A narrow steep flight of short steps ensures:

• that animals can grip and jump centrally into the dip,
• that their heads are lower than their rumps at take-off,
• that they jump one at a time, and
• that dip-wash splashing backwards returns to the dip.

The lip of the jumping place experience extreme wear and should be reinforced with a length of 10cm diameter steel pip.

Figure 10.24 shows the jumping place 40cm above the dip-wash level. While such a height is desirable to give maximum immersion, there could be some danger to heavily pregnant cows if the water level was allowed to fall a further 40cm. (The dipping of 1,000 cattle without replensihment would lower the water level to 60cm below the jumping place).

Splash walls and ceiling are provided to catch the splash and prevent the loss of any acaricide. The ceiling will protect a galvanized roof from corrosion. The walls can be made of wood, but masonry is most durable.

Figure 10.23 Cattle dip layout.

Figure 10.24 Cattle dip.

The Dipping Tank

The dipping tank is designed to a size and shape to fit a jumping cow and allow her to climb out, while economizing as far as possible on the cost of construction and the recurrent cost of acaricide for refilling. A longer tank is needed if an operator standing on the side is to have a good chance of reimmersing the heads of the animals while they are swimming, and increased volume can slightly prolong the time until the dip must be cleaned out. In areas with cattle of the 'Ankole' type with very long horns, the diptank needs to be much wider at the top.

Poured reinforced concrete is the best material to use in constructing a dipping tank in any type of soil although expensive if only a single tank is to be built, because of the cost of the form-work involved, the forms can be reused. If 5 tanks are built with one set of forms the cost per tank is less than the cost of building with other materials, such as concrete blocks or bricks. A reinforced concrete dipping tank is the only type with a good chance of surviving without cracking in unstable ground. In areas prone to earthquakes a one-piece tank is essential.

Catwalk and hand rails are provided to allow a person to walk between the splashwalls to rescue an animal in difficulty.

In addition to providing shade, a roof over the dipping tank reduces evaporation of the dip-wash, prevents dilution of the dip-wash by rain, and in many cases, collects rain water for storage in a tank for subsequent use in the dip.

Draining Race

The return of surplus dip-wash to the dipping tank depends on a smooth, watertight, sloping floor in the draining race.

A double race reduces the length and is slightly cheaper in materials, but a very long single race is preferable where large numbers of cattle are being dipped. Side-sloping of the standing area towards a channel or gutter increases the back-flow rate. The total standing area of the draining race is the factor that limits the number of cattle that can be dipped per hour, and the size shown in the drawings should be taken as the minimum.

A silt trap allows settling of some of the mud and dung from the dip-wash flowing back to the tank from the draining race. The inlet and outlet should be arranged so that there is no direct cross-flow. Provision must be made to divert rain water away from the dip.

Cattle Spray Race

A spray race site requires the same features as a dip site and these have already been described. The only difference is that the dip tank has been changed for a spray race. The race consists of an approximately 6m long and 1m wide tunnel with masonry side walls and a concrete floor. A spray pipe system on a length of 3 to 3.5m in the tunnel having 25 to 30 nozzles place in the walls, ceiling and floor, discharge dip liquid at high pressure and expose the cattle passing through to a dense spray. The fluid is circulated by a centrifugal pump giving a flow of 800 litres per minute at 1.4 kg/ cm² pressure. Power for the pump can be supplied by a 6 to 8 horsepower stationary engine, a tractor power take-off, or a 5-horse-power electric motor. The discharged fluid collected on the floor of the tunnel and draining race is led to a sump and re-circulated. In addition to being cheaper to install than a dipping tank the spray race uses less liquid per animal and operates with a smaller quantity of wash, which can be freshly made up each day. Spraying is quicker than dipping and causes less disturbance to the animals. However, spray may not efficiently reach all parts of the body or penetrate a fur of long hair. The mechanical equipment used requires power, maintenance and spare parts and the nozzles tend to get clogged and damaged by horns.

Handspraying is an alternative method that can work well if carried out by an experienced person on an animal properly secured in a crush. The cost of the necessary eqyuipment is low, but the consumption of liquid is high as it is not re-circulated. The method is time consuming and therefore only practicable for small herds where there is no communal dip tank or spray race.

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