Dipping of Farm Animals (Cattle & Sheep /Goats )- Treatment of External Parasites

Dipping of Farm Animals (Cattle & Sheep /Goats )- Treatment of External Parasites

Arthropod pests limit production in the Livestock industry in many ways. External parasites feed on body tissue such as blood, skin, and hair. The wounds and skin irritation produced by these parasites result in discomfort and irritation to the animal. Parasites can transmit diseases from sick to healthy animals. They can reduce weight gain and milk production. In general, infested livestock cannot be efficiently managed.

Ectoparasities of sheep and goats do not generally cause heavy mortalities unless the infestation is extreme, but they will cause unthriftiness and loss of production if not controlled. Animals in poor health or low levels of nutrition are more likely to be affected and young animals are more susceptible.

The main external parasites found in India affecting sheep and goats are

1.    Ticks
2.    Mites
3.    Fleas and lice
4.    Nasal worm (Oestrus ovis)

Ticks

Ticks are more commonly found on goats and unwoolled sheep. They can cause anaemia resulting from blood loss, especially in lambs and kids, and open sores which then become a site for screw-worm infestation.

Ticks also transmit disease – the most common in Zimbabwe being heartwater. They also cause tick toxicosis (sweating sickness) and tick paralysis (also known as Karoo paralysis) These both affect young animals and may be fatal. Tick paralysis may also affect man.

To control ticks, sheep and goats must be dipped regularly with an approved acaracide. (See Dipping Cattle, Sheep and Goats) Most acaricides registered for sheep will control ticks, mites and lice.

Mites

There are many species of mites, but most are harmless. The two economically important conditions caused by mites are SHEEP SCAB and MANGE.

• Mange is caused by several different species but the most important are Sarcoptes Spp which cause Sarcoptic Mange. This is a contagious condition more common in goats than sheep, and rarely seen in woolly sheep. The mites burrow into the skin of the animal causing thickening and wrinkling of the skin with thick crust formation. Other mites include Psoroptes caprae found in the ears of goats, which can result in deafness if not diagnosed and treated. Chorioptes Sp are found on the legs of goats and horses. It causes extreme itchiness and the affected animal will often stamp its legs continually.
• Sheep scab(See picture) is a scheduled disease, luckily not commonly found in Zimbabwe. It is caused by the mite Psoroptes ovis and is highly contagious. It is found only in sheep and the mite does not live anywhere but on the body of the sheep. The life cycle is 10 days in optimum conditions so the spread of disease can be extremely rapid. The mite bites into the skin, feeding on lymph and causing inflammation and irritation. Lymph flows out of the bite wounds, forming thick scabs and causing the wool to drop out. It causes extreme itchiness and distress to the affected animal.

Fleas and Lice

These are found where animals are kept in close confinement, over-crowded and where the environment is warm and humid. Infestation cause anaemia, especially in young animals and damage to the skin leading to losses on hides and wool. Control is by dipping, avoiding over-crowding, regular cleaning of houses and changing of bedding if this is used.

Nasal Bots (Oestrus ovis)

The fly deposits its larvae at the nostrils of the sheep. The larvae or maggots crawl up the nasal passage into the frontal sinuses. The worm grows rapidly in the sinuses, particularly in warm weather and may be fully grown in a month. It has two strong hooks at the front end and is covered in small spines. This obviously causes extreme irritation to the sheep and results in sneezing, head shaking, respiratory distress syndromes and copious nasal discharge. It also may cause secondary bacterial infections. Although the bot does not cause too much damage to the sheep, a heavy infestation causes such irritation that the sheep will feed poorly and lose condition.

Purpose

To eradicate ectoparasites, cure and prevent spread of sheep scab, ward off attacks by sheep blow-flies, remove waste material and dung from the fleece prior to shearing, thus facilitating production of clean wool.

Time : In India, sheep can be dipped immediately before the post-winter shearing and/or before the post-autumn shearing. In addition, they can be dipped 1-4 weeks after shearing, when the fleece has grown long enough to retain dip solution and also allow cuts and scratches incidental to shearing time to heal.

Dipping chemicals : BHC, Lindane (0.25%), DDT (0.5%), Garathion, Malathion (2.0%), Cimathion, Pyrethrin-arsenic sulphide powder (0.2% arsenic), coal tar-creosote (0.76%), nicotine and tobacco dips (0.1% nicotine, 15 kg tobacco leaves in 500 lit water).

Dipping tanks :-

a) Hand bath : In case of small flocks, a tank of galvanized iron (1.2 x 1.0 x 0.5 m) can be used. Sheep can be lifted one by one into the bath and kept for two minutes. The sheep are removed and placed on a drain board to drain off surplus dip back into the dip tank.

b) Swim bath : In large flocks, the dipping tank can be constructed of metal or concrete. It should be 12 feet long at the top and 6 feet long at the bottom, with a incline for the other 6 feet. The tank should be 2 feet wide at the top, sloping to one foot at the bottom, and it should be 6 feet high. The sheep should be completely immersed in the liquid (including their heads and ears).

Precautions :-

1. Follow the manufacturer’s instructions thoroughly for preparation of the dip as well as its disposal.
2. Always water and rest the sheep before dipping to avoid their drinking of dipping solution.
3. Choose a bright, sunny day (neither too hot nor too cold) so that the treated animals will dry quickly and the insecticide will not be diluted by rain.
4. Avoid dipping of sheep in advanced stage of pregnancy.
5. Avoid dipping of sick animals, sheep with wounds, young lambs (less than one month old) and stock being sent for slaughter.
6. Avoid dipping of rams in breeding season to guard against injury to penis or scalding of thigh.
7. Keep sheep in the holding pen for at least five to ten minutes so that they drain properly, thus avoiding wastage of dip and resultant pollution of the environment.
8. Complete each day’s dipping by 4 PM so that the sheep will have some hours to dry before nightfall.
9. Do not return treated sheep to the shed from which they came until it is completely cleaned.

Pouring

When an individual sheep is affected with scab or badly affected with maggots and has open wounds, dipping is not advisable. In such animals, a small quantity of dip is poured into the fleece along the back, sides and belly to achieve the objectives of dipping.

Spraying

Spraying sheep with a fly repellant insecticide solution over the backs and sides is an effective method of controlling ectoparasites in tropical countries. In developed countries, fly-repellant solution is sprayed in the form of a fine mist through a series of nozzles into a roomy tunnel through which the sheep are forced to pass. However, spraying can be done with the help of a power sprayer or hand sprayer in case of small flocks. Spraying is not as economical or efficient as dipping and is recommended only for young lambs which cannot be dipped.

Dipping is an internationally recognised method for treating ectoparasites. Angora goats must be dipped in a controlled and calm way to minimise stress and ensure the thorough application of the ectoparaiste control treatment.

Ectoparasites must be treated to ensure the health and wellbeing of the Angora goats. Other options to dipping include Pour On products and certain injectable products. Speak to your vet.

It is the responsibility of the Mohair producer to ensure the welfare of his goats are taken care of when they are dipped.

Purpose

• To remove waste materials and dung from the fleece, prior to shearing.
• To eradicate ectoparasites.
• To prevent spread of “sheep scab”
• To wart off attacks by blowflies resulting in maggots.
• Dipping is done usually twice a year i.e once before shearing and a second time when the fleece has grown long.

Precautions before dipping

• Do not dip ewes in advanced pregnancy to avoid inducing abortion.
• Always offer water before dipping so that sheep will not drink the dip.
• Always rest sheep before dipping.
•  Do not dip sick animals.
• Dip about a month after shearing when the there is sufficient dip
• Dipping should preferably be completed before noon.
• Allow sheep in a draining pen for sometimes before turning them out on the pasture.
• Chooses a day is possible when the weather is not too hot.
• Dipping should be done during sunny days.
• Care should be taken to avoid contact of eyes and mouth with the solution·
• After dipping place the animal in the open place for quick drying.

Methods of Dipping

• The hand bath used for small flocks. Each sheep is lifted into the bath and turned over on its back.
• The swim bath: this is used for large flocks of sheep.
• The sheep are allowed to swim through and walk up the ramp into the drying pen.
• Sheep dips: the active agents used are

• • Sulphur
  • Arsenic
  • D.D.T. and
  • Carbolic acid etc

• The quantity of dip depends upon the length of the fleece.

Pouring

• means pouring a small quantity of dip into parts of the fleece along the back, sides and belly.

Smearing

• An ointment with a basis of tar and grease is smeared over the skin of the sheep to destroy parasites.

Crutching

• Means removing soiled and dung – stained wool by hand shears from the crutch of the sheep (perineal and inguinal regions).

Jetting

• Is a method adopted in foreign countries in which the sheep are made to run through a race or “shedder” in which is fixed a pipe which plays a jet of water into the lower part of the abdomen and the crutch.

Considerations before dipping:

• Goats should preferably be dipped two to six weeks after shearing, as the Mohair is then long enough to retain dip and hence make the dipping more effective and worthwhile to treat ectoparasites.
• The goats should be separated into various age groups to prevent the larger animals being dipped together with smaller ones.
• The goats must be well and in good condition
• Food should be removed overnight so there is less contamination of the dip by manure. The goats must be provided with clean fresh water before and after dipping.
• Dipping should, as far as possible, be done in early morning on a mild, sunny day. This will allow the animals to dry properly and quickly.
• Hot and tired goats must not be dipped. They should be allowed a period of rest after collection.
• Remember protective equipment for those involved in the dipping process to avoid contact with the treatment.

Dipping procedure:

• Work calmly and quietly, minimise stress
• Each goat should be lowered into the dip tank gently, hindquarters first, and should not be turned on its back.
• The head should remain above the water for a while to allow for normal breathing, and then be submerged twice with a dipping stick, again allowing time for breathing between dipping.
• The goat must be continually checked as it swims through the dip to ensure it does not get into difficulty.
• Mites, lice will move up the body very quickly and reside in dry areas so it is important that the head is submerged. Re-infestation by ectoparisites (especially lice) occurs quickly if the head is not submerged properly. Ensure the goat is breathing comfortably and the goat is not struggling before the head is submerged.
• The distance/time of the swim is important and should be at least 9 m in length or close to a minute in duration.
• Following manufacturer’s guidelines is critical in maintaining a proper concentration of insecticide. The total volume of the dip tank should be carefully calculated for determining the concentration of the dip. The treatment must be thoroughly mixed.
• Replenishment instructions as advised by the manufacturer must be strictly followed.

Considerations after dipping:

• The goats must be monitored in the draining pen.
• The goats should not be driven for long distances immediately after dipping.
• Goats must be provided with fresh clean water.
• Environmental guidelines as stipulated by the RMS must be followed.

 Pests in Cattle – External Parasites

 Livestock production practices, when intensified, create a conducive environment for the multiplication of different pests that reduce animal productivity through competition for food, especially blood feeders, while others act as disease vectors. Some pests are present throughout the production periods and are major challenges to livestock farmers. Some control measures and practices have often resulted in harder-to-control pests due to repeated applications of the same formulation remedy and pest resistance results.

There are two categories of these pests based on the location of their harm to the livestock and they are classified as either internal or external pests. The correct diagnosis is essential. Livestock keepers should be well versed in these various challenges affecting their investments to use the best and economically viable control mechanism to ensure optimal livestock production.

External Parasites

Tick Control

Major losses have been reported in livestock production systems resulting from tick-borne diseases, especially in warm tropical regions. The cattle tick is a significant ectoparasite of cattle and a vector for important diseases such as East Coast Fever, babesiosis and anaplasmosis. Ticks cause physical damage to the animal by feeding on it by sucking blood. The cattle tick is widely distributed, and climatic factors largely determine the distribution. Ticks require high humidity and ambient temperatures of at least 15-20 °C for egg laying and hatching.

Cattle tick infestation causes:  

• Damage to hides;
• Loss of production;
• Anaemia and death,
• Weakness during droughts.

The life cycle involves free-living stages. After feeding on cattle, engorged female ticks drop to the ground and lay eggs (up to 5000). After hatching, the larvae survive on pasture for several months. The larvae then become active, climb up grass, and transfer to animals as they brush past. The larvae attach and feed from the host. A potential risk for introduction to new areas might be transportation through dogs, although egg production is much reduced in this species, and the risk is considered low.

There are four methods available for controlling ticks:  

• Treatment with acaricides
• Pasture spelling
• The use of resistant cattle
• Vaccination

Tick control by acaricide dipping has been widely used in endemic areas. Acaricide used for this purpose includes various synthetic pyrethroids, amitraz, and organophosphates. Dipping may have to be done every 4-6 weeks in heavily infested areas.

Cattle are the main hosts for cattle ticks although they may be found on horses, goats, sheep, deer, camel and buffaloes. Heavy infestation of cattle ticks causes loss of condition and even death because of blood loss. Thicks can also carry and transmit tick fever which cause death and sickness in cattle. If cattle are heavily infested, ticks can be found anywhere on their body. The main places to look on a lightly infected animal are the neck, tail, belly, shoulder, dewlap and ears. Tick bites damage the hides of heavily infested animals. In severe cases hides may become unsaleable.\

Cattle are particularly vulnerable when they first encounter cattle ticks but develop a degree of resistance after repeated exposure. Indigenous breeds (tropical breeds) and their crosses develop better resistance than exotic breeds. Horses, goats and sheep also suffer tick problems but after some time,  they develop strong resistance. The best time to identify the cattle tick is at the adult stage.

Life cycle

Adult females feed for a week, then lay eggs and die. They can lay up to 3000 eggs, and then they die. The eggs hatch into larvae, which can survive on pastures for 2 (warm weather) to 7 (cold weather) months until they find a host. The cattle tick spends about 21 days on one host, during which it goes from a larvae to a nymph and then an adult. Males feed occasionally, but they don’t fill with blood. Cattle ticks can be controlled with resistant cattle, chemical treatments, the cattle tick vaccine, pasture spelling, or a combination of methods. However, resistance to chemicals is a growing problem. Hand dressing is effective but labor-intensive. Using a combination of methods is usually necessary to control tick infestations.

Dipping

To ensure that dipping is both safe and effective, the following principles should be observed:

1. The bath should be roofed to prevent dilution of the acaricide by rain or evaporation hot during the weather
2. The bath must be long, wide, and deep enough to ensure complete animal immersion without injury. These should be access along its whole length to enable help to be brought to any animal in difficulty and to enable an operator, stationed at the side of the bath to duck the head of each animal by means of a dipping crutch.
3. When the required amount of acaricide has been measured out it must be evenly distributed over the bath surface. The animal should have a second dipping
4. The full dip-tank volume should be accurately measured. This should be done at the time of filling (for example, by counting the number of 200 litres drum-full of water it takes to fill the dip-tank
5. The dip tank should be accurately calibrated
6. To mix it, 20 cattle should be passed through the dip at the beginning of dipping. After these cattle should drained and pass through the dip again
7. Each animal should be totally submerged at least once
8. The dipped cattle should be allowed to drain for only 2-3 minutes in the drainage race before releasing them. This results in a wash consumption of 2-21/2 litres per head
9. Ear fringes and trail brushes must be clipped once every six weeks
10. A sample of the dip wash should be taken for analysis once a month. This should be taken while the dip wash is still very agitated after the passage of at least 50 heads or immediately after the last animal has been dipped.
11. The dip tank should be emptied and cleaned once every year
12. Cattle that are hot, tired and thirsty should not be allowed to rest and drink before the treatment
13. Dipping should be carried out early morning
14. Calves should be treated after the treatment of adult cattle
15. Calves under one month of age should be treated with care and attention

Spraying

The mechanical spray race

1. The spray race should be built across a slight slope and at right angles to the prevailing winds
2. The spray race, the sump housing and the power source should be roofed
3. The sump should be filled with water regarding the number of animals which will be treated – allow 2.5 litres per animal and an additional 300-500 litres, depending upon the race, for the sump.
4. It is essential that the spray race carries a pressure gauge and that the recommended pressure is maintained (1-1.4bar)
5. The spray race should be checked before any animal is treated to ensure that there is sufficient pressure, the nozzles are clear and that the spraying works correctly.
6. The sump should be cleaned out between treatments.
7. The sump tank should be accurately calibrated by pouring water into the sump from 200litre and/ or 20litres drums and making off the various levels on a dipstick.
8. The prepared spray wash should be allowed to circulate for 5 minutes through the entire spray race system before spraying commences
9. Two-foot baths must be filled with clean water before the animals start going through the spray race. The footbaths should be cleaned out after the spraying
10. The sprayed animal should drain for 2-3 minutes before being released. This results in a wash consumption of 2-21/2litres per head
11. Ear fringes and tail brushes of cattle should be clipped every six weeks
12. Cattle that are hot, tired or thirsty should not go through the spray race. They should rest and drink before.
13. Spraying should be carried out early morning
14. The animals should be rushed through the spray race
15. Calves should not be sprayed along with adult cattle. The calves should be allowed to go through the spray race after the adults
16. Calves under one month of age should be sprayed with due care and attention

Hand spraying

1. The wash is delivered via one or two lances either manually or by a motor-operated pump
2. Depending on the number of cattle to be sprayed, they may be restrained in a race in single file or a single animal crush
3. The recommended operating pressure for hand spraying is 3 bar with each lance delivering 3.5-4.5litres of wash per minute as a fine spray
4. The wash can be placed in a bucket. ( for each animal, 9-13 litres of wash is used normally)

The following routine should be followed to achieve adequate wetting of the whole animal:-

1. Spray the hind legs, under the scrotum and the tail. The tail should be laid along the back while being sprayed to prevent unnecessary wastage of wash
2. Spray the belly of the animal, followed by the flanks and backline
3. Spray the front legs, brisket, neck, head and ears
4. Spray the inside of the ears last

Mange (Cattles) 

Mange is a condition caused by mites, which look like small arachnids similar to spiders, mites, can infect and harm the skin of both domestic animals and humans. Problems can occur all year round. Three main species of mite affect cattle, the surface mite, the burrowing mite and the sheep scab mite. The surface mite is the most commonly seen.

Usually, the mites are found on the neck, legs, and tail head. It can cause limited hair loss, which increases slowly. However, the lesions are very itchy, resulting in hide damage as the cattle try to rub the affected areas.

The scab mite in sheep is found on the flanks and around the tail head, and anus. Although this mite feeds on the skin’s surface, its mouthparts pierce the skin, producing blisters, which can be very irritating.

The burrowing mite prefers the neck and the loin area next to the tail (leading to the description of the ‘neck and tail’ mange). As the mites burrow into and out of the skin, they produce a much more intense irritating reaction causing skin damage rapidly. In much larger areas, the skin becomes very thickened and crusty. Infection of the damaged areas often develops and affected animals have reduced production.

Life cycle

The surface mite and the sheep scab mite spend their entire life cycle on the skin’s surface. Females lay around 90 eggs which, once hatched, take about ten days to develop into mature adults.

The burrowing mites’ lifecycle is more complex. The female mite tunnels into the animal’s skin and lays around 50 eggs. These hatch in four or five days, each releasing a larva. Some of these tunnel to the surface to become adults, while others develop in the tunnels; this process takes around two weeks. More tunnels are often formed during the mating process.

Infection is spread mainly by direct contact between cattle for all three species. The burrowing mite can survive for some time off the host. Therefore for this species, bedding and other objects that come into contact with the infected animals may become contaminated and help spread the infection.

A range of products is available to treat mange in cattle. The choice is between pour-on products and injections. The first ones are easier and quicker, and cheaper to use. However, in severely infected animals (as is often seen in burrowing mite problems), the skin reaction can mean that contact between the product and the mite is limited. In such cases, scabs may have to be removed before treatment. If very severe situations, injectable products are better. For very severe surface mite problems, the injection should be followed up by a pour-on treatment when the skin has recovered. This happens because in these species (unlike the burrowing mite), injections can control but do not eliminate.

 

Compiled  & Shared by- Team, LITD (Livestock Institute of Training & Development)

 Image-Courtesy-Google

 Reference-On Request.

Control of External Parasites of Sheep and Goats