Parasites and Parasite Control
May 22, 2016 5:06:52 GMT 10
Post by Tom Meulman on May 22, 2016 5:06:52 GMT 10
Parasites and Parasite Control
Parasites may be divided into two groups, internal parasites and external parasites.
To treat both these groups effectively you need to know as much as you can about their life cycle, the part of the body they invade and the likely signs of their presence, particular during the summer months when both internal and external parasites tend to thrive.
The kennels and yards may also require treating when a severe infestation occurs.
Treatment of kennels and yards must be done in such a way, that any chance of toxicity to the greyhound is avoided.
There are two main categories of worms; they are Round - Hook & Whipworms (NEMATODES) and Tapeworms (CESTODES).
It is the Nematodes that cause the most amount of damage to the greyhounds system, mainly because part of their lifecycle involves travelling through the greyhound’s body, not just living in the gut or the intestines, even though that on its own is bad enough.
Internal Parasites Nematode group
Roundworms 2 species, TOXASCARIS LEONIA and TOXASCARIS CANIS
Adults of both species are round, tapering to a point at each end, cream coloured, and may vary in length from 7 to 18 centimetres (3 to 7 inches)
Greyhounds become infested by swallowing the eggs off the ground in a contaminated yard, or even by licking contaminated dirt of their feet or coat.
Once ingested, the larva hatches out of the egg and start maturing into adults. It is probably interesting to note that it is in fact the dog’s own digestive juices that assist in the hatching process.
Toxascaris Leonia
The lava of this species burrows into the wall of the small intestine and in the process causes inflammation and interferes with the intestines ability to absorb nutrients effectively.
The most damage occurs in young pups, the typical signs are; thin potbellied pups, with a dry staring coat and a likelihood of intermittent diarrhoea or constipation.
Toxascaris Canis
These are the more common of the two species and the more dangerous to the health of the dog.
The larva of this species will penetrate the intestinal wall and migrate through the blood vessels to the lungs, once there, the inflammation they cause will make the pup cough, bringing the larva into the throat and they are then swallowed.
Re-entering the small intestine they mature into adults and continue the cycle.
Pups with large numbers of these parasites can die from the damage done by the larva.
The larva also migrate into the muscle tissue and other body organs where they may stay dormant for years, only being reactivated by a bitches pregnancy, pass across the uterus and infest the unborn puppies.
Due to this part of the worm’s life cycle many pups are born with roundworm infestation, making it imperative that all pups are wormed regularly.
Pups infested with Toxascaris Canis roundworm will not only have all the symptoms such as being thin with a potbelly, but will also have an intermittent cough and possibly laboured breathing, if enough lung damage has been done.
It takes only 3 weeks for roundworm larva to mature into adults and start laying eggs, for this reason worm the pups at two weeks of age and then every two weeks until at least 3 months of age.
Brood bitches must be wormed before whelping, preferably during the third to sixth week of pregnancy.
To reduce the chance of re-infestation, yards should be cleaned daily during the dry weather and twice daily when it is raining to avoid the eggs being washed into the soil. (That's what should be done but we all know it seldom happens)
Hookworms
3 species in total, 2 types of the ANCYLOSTOMA variety and 1 called UNCINARIA.
Hookworms are small worms, 7 to 16 millimetres in length as adults (5/16 to 5/8 inches) grey in colour until they drink blood when they will look redish pink.
From all the worms that may affect a greyhound, hookworms can cause the most amount of damage due to the fact that they bite into the wall of the intestine and drink blood.
In many respects they resemble mosquitoes in this action, as in order to drink the blood, they first inject a substance that stops the blood from clotting.
Those of you that have greyhounds would have seen a greyhound puppy with a coat where much of the hair shows a distinct kink or hook at the end of each hair.
This is often seen in pups after they have been reared at a property where the soil has become severely contaminated by hookworm larva due to neglect by the proprietor.
It is the substance injected by the hookworm to keep the blood flowing that causes toxicity in the body and it is the toxicity that causes the hooky hair.
To a lesser extent this hooky hair is also seen in greyhounds suffering toxicity due to other causes.
The other interesting aspect of hookworm infestation is this: as you can imagine the greyhound is infested with hookworm and each of the adult worms is producing larva.
If all the larva so produced mature into adults and start drinking blood it would not be long before the host died, and all the worms along with it, not a very efficient way for a parasite to behave.
To stop this from happening the hookworm produces an enzyme in its faeces that stops the larva from maturing, and so limiting the number of adults.
This creates a problem when you treat the hookworm infestation, because the wormer will only kill the adult worms, once they are gone more larva’s mature, and the process starts all over again.
Therefore to treat a greyhound for a hookworm infestation, it is essential that the treatment be repeated every two weeks for a minimum of three doses.
Ancylostoma Hookworms
The larva of the Ancylostoma hookworm thrives in damp conditions, such as moist concrete and sand.
Greyhounds may become infested by eating the larva of the ground or by the larva penetrating the skin of the greyhound between the toes and the skin under the chest or abdomen.
Ingested larva enters the small intestine and develops into adults.
Some of the larva that enter via the skin, migrate through the blood stream to the lungs where they are coughed up and swallowed, again entering the intestine and maturing into adults, while other larva, after penetrating the skin lodge in the muscle tissue where they stay dormant until activated by late stage pregnancy.
They then make their way to the mammary gland, invade the milk, infesting the pups while they are suckling, making it a real possibility that pups at one month of age will be infested by adult worms.
As always the signs of an infestation are most severe in young puppies, as they cause massive blood loss and anaemia.
Pups with a severe infestation will show pale gums, weight loss, weakness, dry staring coat, and dark coloured manure due to the blood in it, and may die suddenly.
Uncinaria Hookworms
Greyhounds infested with this species of hookworm will show milder signs of infestation such as failure to thrive, poor coat and depression.
Greyhounds do acquire some resistance to repeat infestation of hookworm with age or after having been exposed to infective larva.
As always prevention from infestation requires cleanliness and good animal husbandry.
Contaminated yards maybe treated with a Chlorine spray, after which lime is raked through the soil and the yard rested for at least 4 weeks.
As mentioned earlier hookworm larva thrive on wet concrete, therefore in kennels where the floor is hosed daily to remove urine and faeces, and where there is poor ventilation a real chance exists of continuing infestation from hookworm larva.
Whipworms
Whipworms as their name implies have a thin front section and a thicker rear half and are 4 to 8 centimetres in length (1-1/2 to 3 inches).
The eggs of the Whipworm can survive in the soil or dirt in the kennels for several years and greyhounds become infested after eating the eggs off contaminated ground.
After ingestion the eggs hatch and within 6 weeks to 3 months, the larva’s develop into adult worms in the large intestine.
Heavy infestations cause signs of diarrhoea (sometimes containing blood), abdominal pain and weight loss. Because whipworms also suck blood from the greyhound a heavy infestation may also cause various degrees of anaemia.
Unlike round or hookworm infestations, the symptoms of the whipworm develop slowly over a period of 2 to 3 months and may therefore be easily misdiagnosed and treated as a basic health problem.
Diagnosis of whipworm infestation is made by finding the barrel-shaped eggs in a faecal examination.
Heartworm
Within the NEMATODE group of internal parasites is a blood parasite DIROFILARIA IMMITIS, commonly known as heartworm.
Heartworms are a major danger to greyhounds in areas of Australia where there are high temperatures, humid conditions and the presence of a certain species of mosquito.
While formerly limited to the northeastern states of Australia, the incidence of heartworm infestations appears to be spreading to the southern states.
This is aided by the fact that many trainers based in the south are taking their greyhounds north for specific races without taking the appropriate measures to protect their greyhounds against heartworm.
The parasite is a roundworm whose larval stage of its lifecycle is passed from greyhound to greyhound by a mosquito.
When a mosquito infected with the larva bites a greyhound the larva go into the tissue.
There over approximately 70 days, the larva goes through maturation stages and enters the blood vessels that carry the blood from the heart to the lungs.
Once there, the larva grow into adult worms that measure between 12 to 30 centimetres (4 to 12 inches) long and start producing larvae called MICROFILARIA in 85 to 120 days after the initial infection by the mosquito.
Heartworms cause inflammation of the blood vessel walls and partial blockage of blood flow and may survive for as long as 7 years.
A Greyhound may be infected with the adult worms for up to 9 to 10 months without showing any outward symptoms, while in the later stages of infestation performance will be compromised due to the reduced blood flow to the tissues.
Greyhounds may develop a chronic cough or may collapse or show weakness after a race or trial, the severity of the symptoms depending on the degree of blockage of the blood flow.
In addition the right side of the heart enlarges and may result in fluid accumulation in the lungs, kidneys and liver.
A worsening of the symptoms is seen when adult worms die or are killed by medication, due to worm fragments blocking blood flow in the lungs, resulting in severe coughing, bringing up blood tinged fluids from the lungs and difficulty in breathing.
These greyhounds will need immediate care by a Veterinarian as heart failure may occur and sudden death of the greyhound.
A diagnosis of heartworm infestation is made by either detecting the microfilaria in a blood test or testing for the antigens produced by the adult worms.
Prevention of heartworm infestation is a far better option that trying to treat an affected greyhound.
A once a month dose of IVERMECTIN (Heartgard) prevents heartworm disease by destroying the larva up to one month after an infective mosquito bite, the dose depending on the greyhound’s weight.
MILBEMYCIN OXIME (Interceptor) not only prevents heartworm disease by eliminating the larva, but also treats hookworm infestation, and is suitable for pups from 8 weeks of age.
Cestodes
Tapeworms, 3 species, TAENIA SPECIES, DIPYLIDIUM CANIUM and HYDATID SPECIES
Greyhounds become infested with the Taenia tapeworm by eating meat from infested sheep and cattle, or by eating rodents or rabbits.
The more common tapeworm Dipylidium Caninum infests the greyhound when they bite at and ingest fleas or lice.
Many people have the habit of picking a flea off their dog and squashing it between the fingernails, I doubt they would continue to do so if they realized that that is the surest way of getting tapeworms themselves.
The Hydatid tapeworm infests the greyhound when they eat offal from infected sheep.
You can tell by the appearance of the tapeworm segments which species has infested your greyhound. The first species the Taenia tapeworm has flat, thin white segments; the second species the tapeworm Dipylidium has pink moving segments about 1 centimetre in length.
The Hydatid tapeworm has extremely small pink segments similar to the Dipylidium species but only about one-quarter the size.
These segments may be noted in the manure of infested greyhounds, or if the infestation is severe, on the hair around the anal area.
While the tapeworm does no specific structural damage to the intestines or the organs, the reality is that a tapeworm does a lot of harm to the general health of the greyhound.
The tapeworm is nothing more than a factory producing eggs; the head of the tapeworm is embedded in the wall of the gut, while the rest of the worm extends throughout the intestines.
The tapeworm has no gut, no intestines, it does not eat food, but absorbs nutrients and amino acids directly into its body, and those nutrients are no longer available to the greyhound. Because a tapeworm is about 40% nervous system, the main nutrients it takes away from the greyhound are those amino acids required for building and maintaining a healthy nervous system.
A common reason for pups that are reared while infested with tapeworm, being more nervy and timid than their littermates
Protozoa
2 species, COCCIDIA, GIARDIA
Coccidia are a single celled organism that invades the intestines of the greyhound, rapidly multiplying and causing massive inflammation throughout the digestive system.
Greyhounds suffering from Coccidiosis may have diarrhoea, vomiting, fever, and reluctance to eat. The diarrhoea is severe, often containing blood, the overall effect of the infestation causing dehydration weakness and depression.
Finding the eggs in the manure when examined with a microscope will provide a positive diagnosis.
TREATMENT:
Sulfadimethoxine at 27.5 mg per kg of body weight twice a day for 7 to 10 days
Or Nitrofurazone at 11 mg per kg of body weight daily for 7 to 10 days.
Giardia are also a single celled organism that invade the small intestine of the Greyhound, but unlike Coccidia there is less inflammation and therefore the symptoms are not as severe, except in pups where there is often severe mucous diarrhoea sometimes with blood. The lining of the intestine coming away is what causes the mucous appearance of the diarrhoea.
In adult greyhounds the manure is produced as a soft mound (cow plat).
As with Coccidia infestation the overall result will be dehydration, weakness and depression.
In the case of Giardia Canis, finding the parasite in the manure, not the eggs during microscopic faecal examination, provides the diagnosis.
TREATMENT:
Metronidazole (Flagyl) at 66 mg per kg of body weight daily for 5 days, repeat treatment may be required, as this strain of Protozoa is resistant to treatment.
A high protein diet is beneficial in aiding the recovery from Protozoal infestations.
Many Protozoa infestations are often caused by a contaminated water supply
Neosporosis
There is now no doubt that the disease is here, as the ANZGA has confirmed laboratory reports of its presence in blood samples taken from clinical cases seen by veterinarians in several States of Australia.
However, we currently have no indication as to the prevalence of the infection in breeding and racing stock – or, what steps must be taken to control or eliminate the disease.
Neosporosis is caused by the coccidian organism – Neospora Caninum – and there are at least three well-defined clinical syndromes (disease symptoms), namely:
1. Reproductive – in which the pregnant bitch may present with a greenish black vaginal discharge heralding a pending abortion – usually in the last three weeks of pregnancy.
Consequently, some pups are born dead, while those surviving fail to thrive. Those that do survive will remain small in stature and commonly develop a hopping gait, which progresses to a spastic paralysis of the hind limbs, and a fatal outcome.
The infected bitch often has a personality change leading to a loss of motherly behavior during the latter term of pregnancy, and aggression towards the surviving pups.
2. Musculoskeletal – where greyhounds that are physically fit exhibit generalized muscle soreness after a handslip, trial, race, or even the stress of long car or plane travel. Trainers, and their vet, inevitably confuse this with an Acidosis (Exertional Rhabdomyolysis) attack, even though the workload was nowhere near severe or hard enough to induce an Acidosis.
Repeated attacks often lead to suspecting that the greyhound has some genetic predisposition to Acidosis, or, has “a weak constitution and poor muscle structure”.
3. Neurological – this occurs when the Neospora invade the brain and spinal cord causing fits or convulsions in the catching pen after a trial or race. At other times, the trainer observes muscle twitches in the head or limb muscles, or, repeated attacks of muscle cramp after even mild exercise runs.
Breeders and trainers must be aware that all three of the above syndromes have been observed, and positively diagnosed with laboratory confirmation by blood testing of greyhounds, in at least three States.
The full life cycle of the organism has not been determined as yet, but university research has shown that the dog is the definitive (natural) host for Neospora Caninum – and surprisingly, it has been proven to be a major cause of abortion in dairy cattle, beef cattle, and sheep, both in Australia, New Zealand, as well as in Europe, and America.
Neospora are transmitted directly from mother to pups in the womb during pregnancy. They are also spread in the droppings of infected canines, and are known to be transmitted in fresh meat from infected cattle. Fortunately, cooking infected meat for 15 minutes, and, even freezing infected meat for 24 hours will destroy the organism.
There are treatments available for infected greyhounds, but despite this, longstanding symptoms may not be resolved completely.
Diagnosis requires a special blood test – an Immuno Fluorescent Antibody Titre test (IFAT Test) – in which 10 milliliters of whole blood are centrifuged to extract a few milliliters of serum for submission to the laboratory for analysis.
External Parasites
Fleas
There are several species of fleas that affect greyhounds and they tend to be a continuous problem for some trainers, but more often a problem for rearing kennel proprietors.
They are one of the most common causes of skin irritations in greyhounds and the most common cause of tapeworm infestations.
Only the adult fleas are seen on the dog, the eggs and the larva are found in the soil and bedding.
Rules of Greyhound Racing prohibit greyhounds with a flea infestation from competing in a race.
(Australian Greyhound Racing Rules, Rule 28)
While I have some sympathy for the boarding kennel proprietor who has some difficulty controlling the flea population, I personally have no time at all for the so-called greyhound trainer who presents their greyhound for kennelling when it is infested with fleas.
In correctly constructed racing kennels with the appropriate level of cleanliness there is no excuse at all for any greyhounds to be suffering a flea infestation.
And suffer they do, I am sure not one trainer with fleas on their dog, could handle having those same fleas on themselves for half an hour, I can guarantee they would be ripping their gear off and jumping under a shower.
I suggest that anyone that has a flea problem with his or her racing greyhounds reads page 145 Care of the Racing Greyhound and takes a long hard look at their kennels. It’s not difficult to clean the kennels properly; seal up all the cracks with a silicon sealant, and to provide bedding that can be washed or replaced every couple of weeks.
However, I do have one concern with the use of flea killing substances, there are only two species of animal on this earth that are extremely sensitive to liver damage from the Cholinesterase inhibiting compounds found in flea killing products, and they are Brahma cattle and GREYHOUNDS.
When treating greyhounds for flea infestations, the product label should be carefully read and products listed, as Cholinesterase inhibiting should avoided, or at least used strictly as directed.
There are other products on the market that are more effective and less toxic to greyhounds unfortunately they are also rather expensive, but there again what is the cost of possibly damaging the greyhounds liver and destroying a racing career before it starts.
Whenever possible avoid the use of products containing MALDISON or DIAZINON.
If these products are to be used as a spray to kill flea infestations in the kennels, leave on for 48 hours, then thoroughly clean all sprayed surfaces with a detergent and leave for a further 48 hours before allowing greyhounds access to the area.
Fly bite dermatitis
This is exactly what the name suggests, that is DERMA meaning skin and ITIS meaning inflammation.
Fly bites on the ears are a problem generally confined to the summer months, and occur mainly at the tips of the ears. And it sounds so simple, the flies bite the dog on the tips of the ears, it causes dermatitis and you treat the problem with fly repellent and healing ointment, end of problem.
But lets look at this logically, why should the flies bite the dog on exactly the very tips of the ears?
Simple, the flies buzz around the dog’s head looking for moisture and protein, and I’m sure dogs smell great to flies. The dog vigorously shakes it head to get rid of the flies, the shaking forces a little fluid out of the hair follicle’s at the tips of the ears, and fly says great dinner has arrived and attacks a little harder.
So the dog shakes its ears some more and so on, until the end result is burst capillaries at the tips of the ears, black crusty scabs and Fly Bite Dermatitis.
Simple solution, keep the flies out of your racing kennels in the same manner as you would keep them out of your own house.
Lice
Infestations are thankfully uncommon in greyhounds, and represent a management problem and are easily cleared up by two treatments a week apart with an insecticide for lice.
My own thoughts on the matter are that any greyhound trainer with lice on his greyhounds needs their registration revoked and a swift kick under the butt of their tail.
Mites
Of the mites that infest the dog three are of importance, 2 species of mange causing mites, Demodectic mange mites and Sarcoptic mange mites, and 1 species of ear mites.
Demodectic Mange
Demodectic mange is an inflammatory disease of the skin caused by a larger than normal population of Demodectic mites in the skin. (DEMODEX CANIS)
Most Greyhounds have some mites as part of the normal flora that live on and in the skin, and are acquired from the dam prior to weaning. It is only when there are problems with the dog’s immune system, that they multiply and invade the hair follicles by the thousands, causing inflammation and hair loss.
Demodectic mange is normally only seen in young dogs around 3 to 6 months of age and seldom in dogs older than 18 months and generally only in a small localized area. It usually affects one or two small patches around the eyes or lips and occasionally on the front legs or elsewhere on the body, and may clear up without treatment as the immune system recovers.
Treatment consists of gently rubbing in a topical Rotenone ointment to the affected area daily for 2 to 3 weeks or applying 1 ml of ECTODEX daily for 5 days and repeating the treatment after 3 or 4 days. To reduce the itchiness and allergic reaction it is advisable to also provide daily oral treatment with Prednisolone tablets.
In approximately 10% of the affected dogs the problem spreads all over the body, as a result of a genetic defect in the immune system. It is one of the most severe forms of skin diseases and can result in the death of the dog.
In the racing greyhound the treatment of the generalized form of Demodectic mange is possibly not warranted, for two reasons, (1) the treatment is difficult and not always successful and (2) because the problem is caused by a genetic defect the greyhound should not be bred with.
Examining skin scrapings under the microscope and identifying the mite involved provides the diagnosis for Demodectic mange.
Sarcoptic Mange
Sarcoptic mange is an inflammatory disease of the skin caused by SARCOPTES mites.
The mites burrow and eat their way into the skin, causing an extremely itchy, reddened scabby area with hair loss and secondary bacterial infections. It mainly affects elbows, hocks and the underside of the chest, in other words all the areas where a dog may cause some trauma to the skin by laying on contaminated concrete or nonexistent bedding; occasionally it will also affect the abdomen and earflaps.
As with other mite infestations, it is diagnosed by taking skin scrapings and examining those under a microscope.
In the case of Sarcoptic mange several scrapings may be required, as the numbers of mites causing the damage is much smaller than in Demodectic mange, making identification more difficult, however the affected area will have a distinct “mousy” odour.
Sarcoptic mange is highly contagious, and particularly in the case of pups kennelled together, it is likely that most of them will be affected.
Treatment is based on bathing the area once a week with an insecticidal shampoo or flea wash for 3 treatments and the daily application of a skin softening soothing antibacterial cream. As for other infestations that cause itchiness, oral treatment with Prednisolone is indicated.
Ear Mites
In young Greyhounds, ear mite (OTODECTES CYNOTIS) infestations can be quite common and not normally a major health problem but will require treatment as soon as the problem is noted to avoid the more serious secondary bacterial infections.
The mites are small and white and may be seen in the ear with a magnifying glass, they feed on tissue fluids and waxy secretions, the affected ear will be inflamed and showing a black sticky discharge.
Treatment involves gently cleaning the affected ear with cotton swabs moistened with warm soapy water and treatment with the appropriate eardrops 3x daily, such as OTERNA, VETIOX or VS Eardrops.
Ticks
2 species, DOG PARALYSIS TICK (IXODES HOLOCYCLUS) and the BROWN DOG TICK (RHIPICEPHALUS SANGUINEUS)
The dog paralysis tick is found in the northern warmer regions of Australia and as the name implies causes progressive paralysis starting at the hind limbs, and includes disturbed limb co-ordination, respiratory failure and if the infestation is severe enough, death of the infected animal.
The first signs that are noted are a higher pitched bark, depression and limb weakness on standing or turning quickly.
Tick species may cause anaemia as each life cycle engorges on blood, the other problem that ticks may cause is an infestation of the Protozoa that causes a disease called BABESIOSIS, and this causes severe anaemia and liver damage.
Treatment revolves around removal of the ticks and supportive treatment, and in the case of a severe infestation of the paralysis tick, treatment with an antiserum. In areas where there is a tick infestation, careful daily examination of the skin for ticks is extremely important as a preventative measure.
This includes inspecting the inside of the ears as well as between toes, with ticks having been found on the inside of the edges of the mouth.
While there are a number of products on the market designed to stop a tick from attaching themselves to the dog, they have a very limited and short term effect, and are often toxic to greyhounds. While some of the latest products designed to kill the tick as soon as it ingests blood have also not been proven to be safe to use with greyhounds.
In areas where ticks are prevalent the safest option is to ensure that grass is cut short in yards, and that there is no long grass or any bushes along fence lines where ticks can attach themselves to your greyhounds. This combined with regular grooming and careful daily examination should keep the tick problem to a minimum.
Parasites may be divided into two groups, internal parasites and external parasites.
To treat both these groups effectively you need to know as much as you can about their life cycle, the part of the body they invade and the likely signs of their presence, particular during the summer months when both internal and external parasites tend to thrive.
The kennels and yards may also require treating when a severe infestation occurs.
Treatment of kennels and yards must be done in such a way, that any chance of toxicity to the greyhound is avoided.
There are two main categories of worms; they are Round - Hook & Whipworms (NEMATODES) and Tapeworms (CESTODES).
It is the Nematodes that cause the most amount of damage to the greyhounds system, mainly because part of their lifecycle involves travelling through the greyhound’s body, not just living in the gut or the intestines, even though that on its own is bad enough.
Internal Parasites Nematode group
Roundworms 2 species, TOXASCARIS LEONIA and TOXASCARIS CANIS
Adults of both species are round, tapering to a point at each end, cream coloured, and may vary in length from 7 to 18 centimetres (3 to 7 inches)
Greyhounds become infested by swallowing the eggs off the ground in a contaminated yard, or even by licking contaminated dirt of their feet or coat.
Once ingested, the larva hatches out of the egg and start maturing into adults. It is probably interesting to note that it is in fact the dog’s own digestive juices that assist in the hatching process.
Toxascaris Leonia
The lava of this species burrows into the wall of the small intestine and in the process causes inflammation and interferes with the intestines ability to absorb nutrients effectively.
The most damage occurs in young pups, the typical signs are; thin potbellied pups, with a dry staring coat and a likelihood of intermittent diarrhoea or constipation.
Toxascaris Canis
These are the more common of the two species and the more dangerous to the health of the dog.
The larva of this species will penetrate the intestinal wall and migrate through the blood vessels to the lungs, once there, the inflammation they cause will make the pup cough, bringing the larva into the throat and they are then swallowed.
Re-entering the small intestine they mature into adults and continue the cycle.
Pups with large numbers of these parasites can die from the damage done by the larva.
The larva also migrate into the muscle tissue and other body organs where they may stay dormant for years, only being reactivated by a bitches pregnancy, pass across the uterus and infest the unborn puppies.
Due to this part of the worm’s life cycle many pups are born with roundworm infestation, making it imperative that all pups are wormed regularly.
Pups infested with Toxascaris Canis roundworm will not only have all the symptoms such as being thin with a potbelly, but will also have an intermittent cough and possibly laboured breathing, if enough lung damage has been done.
It takes only 3 weeks for roundworm larva to mature into adults and start laying eggs, for this reason worm the pups at two weeks of age and then every two weeks until at least 3 months of age.
Brood bitches must be wormed before whelping, preferably during the third to sixth week of pregnancy.
To reduce the chance of re-infestation, yards should be cleaned daily during the dry weather and twice daily when it is raining to avoid the eggs being washed into the soil. (That's what should be done but we all know it seldom happens)
Hookworms
3 species in total, 2 types of the ANCYLOSTOMA variety and 1 called UNCINARIA.
Hookworms are small worms, 7 to 16 millimetres in length as adults (5/16 to 5/8 inches) grey in colour until they drink blood when they will look redish pink.
From all the worms that may affect a greyhound, hookworms can cause the most amount of damage due to the fact that they bite into the wall of the intestine and drink blood.
In many respects they resemble mosquitoes in this action, as in order to drink the blood, they first inject a substance that stops the blood from clotting.
Those of you that have greyhounds would have seen a greyhound puppy with a coat where much of the hair shows a distinct kink or hook at the end of each hair.
This is often seen in pups after they have been reared at a property where the soil has become severely contaminated by hookworm larva due to neglect by the proprietor.
It is the substance injected by the hookworm to keep the blood flowing that causes toxicity in the body and it is the toxicity that causes the hooky hair.
To a lesser extent this hooky hair is also seen in greyhounds suffering toxicity due to other causes.
The other interesting aspect of hookworm infestation is this: as you can imagine the greyhound is infested with hookworm and each of the adult worms is producing larva.
If all the larva so produced mature into adults and start drinking blood it would not be long before the host died, and all the worms along with it, not a very efficient way for a parasite to behave.
To stop this from happening the hookworm produces an enzyme in its faeces that stops the larva from maturing, and so limiting the number of adults.
This creates a problem when you treat the hookworm infestation, because the wormer will only kill the adult worms, once they are gone more larva’s mature, and the process starts all over again.
Therefore to treat a greyhound for a hookworm infestation, it is essential that the treatment be repeated every two weeks for a minimum of three doses.
Ancylostoma Hookworms
The larva of the Ancylostoma hookworm thrives in damp conditions, such as moist concrete and sand.
Greyhounds may become infested by eating the larva of the ground or by the larva penetrating the skin of the greyhound between the toes and the skin under the chest or abdomen.
Ingested larva enters the small intestine and develops into adults.
Some of the larva that enter via the skin, migrate through the blood stream to the lungs where they are coughed up and swallowed, again entering the intestine and maturing into adults, while other larva, after penetrating the skin lodge in the muscle tissue where they stay dormant until activated by late stage pregnancy.
They then make their way to the mammary gland, invade the milk, infesting the pups while they are suckling, making it a real possibility that pups at one month of age will be infested by adult worms.
As always the signs of an infestation are most severe in young puppies, as they cause massive blood loss and anaemia.
Pups with a severe infestation will show pale gums, weight loss, weakness, dry staring coat, and dark coloured manure due to the blood in it, and may die suddenly.
Uncinaria Hookworms
Greyhounds infested with this species of hookworm will show milder signs of infestation such as failure to thrive, poor coat and depression.
Greyhounds do acquire some resistance to repeat infestation of hookworm with age or after having been exposed to infective larva.
As always prevention from infestation requires cleanliness and good animal husbandry.
Contaminated yards maybe treated with a Chlorine spray, after which lime is raked through the soil and the yard rested for at least 4 weeks.
As mentioned earlier hookworm larva thrive on wet concrete, therefore in kennels where the floor is hosed daily to remove urine and faeces, and where there is poor ventilation a real chance exists of continuing infestation from hookworm larva.
Whipworms
Whipworms as their name implies have a thin front section and a thicker rear half and are 4 to 8 centimetres in length (1-1/2 to 3 inches).
The eggs of the Whipworm can survive in the soil or dirt in the kennels for several years and greyhounds become infested after eating the eggs off contaminated ground.
After ingestion the eggs hatch and within 6 weeks to 3 months, the larva’s develop into adult worms in the large intestine.
Heavy infestations cause signs of diarrhoea (sometimes containing blood), abdominal pain and weight loss. Because whipworms also suck blood from the greyhound a heavy infestation may also cause various degrees of anaemia.
Unlike round or hookworm infestations, the symptoms of the whipworm develop slowly over a period of 2 to 3 months and may therefore be easily misdiagnosed and treated as a basic health problem.
Diagnosis of whipworm infestation is made by finding the barrel-shaped eggs in a faecal examination.
Heartworm
Within the NEMATODE group of internal parasites is a blood parasite DIROFILARIA IMMITIS, commonly known as heartworm.
Heartworms are a major danger to greyhounds in areas of Australia where there are high temperatures, humid conditions and the presence of a certain species of mosquito.
While formerly limited to the northeastern states of Australia, the incidence of heartworm infestations appears to be spreading to the southern states.
This is aided by the fact that many trainers based in the south are taking their greyhounds north for specific races without taking the appropriate measures to protect their greyhounds against heartworm.
The parasite is a roundworm whose larval stage of its lifecycle is passed from greyhound to greyhound by a mosquito.
When a mosquito infected with the larva bites a greyhound the larva go into the tissue.
There over approximately 70 days, the larva goes through maturation stages and enters the blood vessels that carry the blood from the heart to the lungs.
Once there, the larva grow into adult worms that measure between 12 to 30 centimetres (4 to 12 inches) long and start producing larvae called MICROFILARIA in 85 to 120 days after the initial infection by the mosquito.
Heartworms cause inflammation of the blood vessel walls and partial blockage of blood flow and may survive for as long as 7 years.
A Greyhound may be infected with the adult worms for up to 9 to 10 months without showing any outward symptoms, while in the later stages of infestation performance will be compromised due to the reduced blood flow to the tissues.
Greyhounds may develop a chronic cough or may collapse or show weakness after a race or trial, the severity of the symptoms depending on the degree of blockage of the blood flow.
In addition the right side of the heart enlarges and may result in fluid accumulation in the lungs, kidneys and liver.
A worsening of the symptoms is seen when adult worms die or are killed by medication, due to worm fragments blocking blood flow in the lungs, resulting in severe coughing, bringing up blood tinged fluids from the lungs and difficulty in breathing.
These greyhounds will need immediate care by a Veterinarian as heart failure may occur and sudden death of the greyhound.
A diagnosis of heartworm infestation is made by either detecting the microfilaria in a blood test or testing for the antigens produced by the adult worms.
Prevention of heartworm infestation is a far better option that trying to treat an affected greyhound.
A once a month dose of IVERMECTIN (Heartgard) prevents heartworm disease by destroying the larva up to one month after an infective mosquito bite, the dose depending on the greyhound’s weight.
MILBEMYCIN OXIME (Interceptor) not only prevents heartworm disease by eliminating the larva, but also treats hookworm infestation, and is suitable for pups from 8 weeks of age.
Cestodes
Tapeworms, 3 species, TAENIA SPECIES, DIPYLIDIUM CANIUM and HYDATID SPECIES
Greyhounds become infested with the Taenia tapeworm by eating meat from infested sheep and cattle, or by eating rodents or rabbits.
The more common tapeworm Dipylidium Caninum infests the greyhound when they bite at and ingest fleas or lice.
Many people have the habit of picking a flea off their dog and squashing it between the fingernails, I doubt they would continue to do so if they realized that that is the surest way of getting tapeworms themselves.
The Hydatid tapeworm infests the greyhound when they eat offal from infected sheep.
You can tell by the appearance of the tapeworm segments which species has infested your greyhound. The first species the Taenia tapeworm has flat, thin white segments; the second species the tapeworm Dipylidium has pink moving segments about 1 centimetre in length.
The Hydatid tapeworm has extremely small pink segments similar to the Dipylidium species but only about one-quarter the size.
These segments may be noted in the manure of infested greyhounds, or if the infestation is severe, on the hair around the anal area.
While the tapeworm does no specific structural damage to the intestines or the organs, the reality is that a tapeworm does a lot of harm to the general health of the greyhound.
The tapeworm is nothing more than a factory producing eggs; the head of the tapeworm is embedded in the wall of the gut, while the rest of the worm extends throughout the intestines.
The tapeworm has no gut, no intestines, it does not eat food, but absorbs nutrients and amino acids directly into its body, and those nutrients are no longer available to the greyhound. Because a tapeworm is about 40% nervous system, the main nutrients it takes away from the greyhound are those amino acids required for building and maintaining a healthy nervous system.
A common reason for pups that are reared while infested with tapeworm, being more nervy and timid than their littermates
Protozoa
2 species, COCCIDIA, GIARDIA
Coccidia are a single celled organism that invades the intestines of the greyhound, rapidly multiplying and causing massive inflammation throughout the digestive system.
Greyhounds suffering from Coccidiosis may have diarrhoea, vomiting, fever, and reluctance to eat. The diarrhoea is severe, often containing blood, the overall effect of the infestation causing dehydration weakness and depression.
Finding the eggs in the manure when examined with a microscope will provide a positive diagnosis.
TREATMENT:
Sulfadimethoxine at 27.5 mg per kg of body weight twice a day for 7 to 10 days
Or Nitrofurazone at 11 mg per kg of body weight daily for 7 to 10 days.
Giardia are also a single celled organism that invade the small intestine of the Greyhound, but unlike Coccidia there is less inflammation and therefore the symptoms are not as severe, except in pups where there is often severe mucous diarrhoea sometimes with blood. The lining of the intestine coming away is what causes the mucous appearance of the diarrhoea.
In adult greyhounds the manure is produced as a soft mound (cow plat).
As with Coccidia infestation the overall result will be dehydration, weakness and depression.
In the case of Giardia Canis, finding the parasite in the manure, not the eggs during microscopic faecal examination, provides the diagnosis.
TREATMENT:
Metronidazole (Flagyl) at 66 mg per kg of body weight daily for 5 days, repeat treatment may be required, as this strain of Protozoa is resistant to treatment.
A high protein diet is beneficial in aiding the recovery from Protozoal infestations.
Many Protozoa infestations are often caused by a contaminated water supply
Neosporosis
There is now no doubt that the disease is here, as the ANZGA has confirmed laboratory reports of its presence in blood samples taken from clinical cases seen by veterinarians in several States of Australia.
However, we currently have no indication as to the prevalence of the infection in breeding and racing stock – or, what steps must be taken to control or eliminate the disease.
Neosporosis is caused by the coccidian organism – Neospora Caninum – and there are at least three well-defined clinical syndromes (disease symptoms), namely:
1. Reproductive – in which the pregnant bitch may present with a greenish black vaginal discharge heralding a pending abortion – usually in the last three weeks of pregnancy.
Consequently, some pups are born dead, while those surviving fail to thrive. Those that do survive will remain small in stature and commonly develop a hopping gait, which progresses to a spastic paralysis of the hind limbs, and a fatal outcome.
The infected bitch often has a personality change leading to a loss of motherly behavior during the latter term of pregnancy, and aggression towards the surviving pups.
2. Musculoskeletal – where greyhounds that are physically fit exhibit generalized muscle soreness after a handslip, trial, race, or even the stress of long car or plane travel. Trainers, and their vet, inevitably confuse this with an Acidosis (Exertional Rhabdomyolysis) attack, even though the workload was nowhere near severe or hard enough to induce an Acidosis.
Repeated attacks often lead to suspecting that the greyhound has some genetic predisposition to Acidosis, or, has “a weak constitution and poor muscle structure”.
3. Neurological – this occurs when the Neospora invade the brain and spinal cord causing fits or convulsions in the catching pen after a trial or race. At other times, the trainer observes muscle twitches in the head or limb muscles, or, repeated attacks of muscle cramp after even mild exercise runs.
Breeders and trainers must be aware that all three of the above syndromes have been observed, and positively diagnosed with laboratory confirmation by blood testing of greyhounds, in at least three States.
The full life cycle of the organism has not been determined as yet, but university research has shown that the dog is the definitive (natural) host for Neospora Caninum – and surprisingly, it has been proven to be a major cause of abortion in dairy cattle, beef cattle, and sheep, both in Australia, New Zealand, as well as in Europe, and America.
Neospora are transmitted directly from mother to pups in the womb during pregnancy. They are also spread in the droppings of infected canines, and are known to be transmitted in fresh meat from infected cattle. Fortunately, cooking infected meat for 15 minutes, and, even freezing infected meat for 24 hours will destroy the organism.
There are treatments available for infected greyhounds, but despite this, longstanding symptoms may not be resolved completely.
Diagnosis requires a special blood test – an Immuno Fluorescent Antibody Titre test (IFAT Test) – in which 10 milliliters of whole blood are centrifuged to extract a few milliliters of serum for submission to the laboratory for analysis.
External Parasites
Fleas
There are several species of fleas that affect greyhounds and they tend to be a continuous problem for some trainers, but more often a problem for rearing kennel proprietors.
They are one of the most common causes of skin irritations in greyhounds and the most common cause of tapeworm infestations.
Only the adult fleas are seen on the dog, the eggs and the larva are found in the soil and bedding.
Rules of Greyhound Racing prohibit greyhounds with a flea infestation from competing in a race.
(Australian Greyhound Racing Rules, Rule 28)
While I have some sympathy for the boarding kennel proprietor who has some difficulty controlling the flea population, I personally have no time at all for the so-called greyhound trainer who presents their greyhound for kennelling when it is infested with fleas.
In correctly constructed racing kennels with the appropriate level of cleanliness there is no excuse at all for any greyhounds to be suffering a flea infestation.
And suffer they do, I am sure not one trainer with fleas on their dog, could handle having those same fleas on themselves for half an hour, I can guarantee they would be ripping their gear off and jumping under a shower.
I suggest that anyone that has a flea problem with his or her racing greyhounds reads page 145 Care of the Racing Greyhound and takes a long hard look at their kennels. It’s not difficult to clean the kennels properly; seal up all the cracks with a silicon sealant, and to provide bedding that can be washed or replaced every couple of weeks.
However, I do have one concern with the use of flea killing substances, there are only two species of animal on this earth that are extremely sensitive to liver damage from the Cholinesterase inhibiting compounds found in flea killing products, and they are Brahma cattle and GREYHOUNDS.
When treating greyhounds for flea infestations, the product label should be carefully read and products listed, as Cholinesterase inhibiting should avoided, or at least used strictly as directed.
There are other products on the market that are more effective and less toxic to greyhounds unfortunately they are also rather expensive, but there again what is the cost of possibly damaging the greyhounds liver and destroying a racing career before it starts.
Whenever possible avoid the use of products containing MALDISON or DIAZINON.
If these products are to be used as a spray to kill flea infestations in the kennels, leave on for 48 hours, then thoroughly clean all sprayed surfaces with a detergent and leave for a further 48 hours before allowing greyhounds access to the area.
Fly bite dermatitis
This is exactly what the name suggests, that is DERMA meaning skin and ITIS meaning inflammation.
Fly bites on the ears are a problem generally confined to the summer months, and occur mainly at the tips of the ears. And it sounds so simple, the flies bite the dog on the tips of the ears, it causes dermatitis and you treat the problem with fly repellent and healing ointment, end of problem.
But lets look at this logically, why should the flies bite the dog on exactly the very tips of the ears?
Simple, the flies buzz around the dog’s head looking for moisture and protein, and I’m sure dogs smell great to flies. The dog vigorously shakes it head to get rid of the flies, the shaking forces a little fluid out of the hair follicle’s at the tips of the ears, and fly says great dinner has arrived and attacks a little harder.
So the dog shakes its ears some more and so on, until the end result is burst capillaries at the tips of the ears, black crusty scabs and Fly Bite Dermatitis.
Simple solution, keep the flies out of your racing kennels in the same manner as you would keep them out of your own house.
Lice
Infestations are thankfully uncommon in greyhounds, and represent a management problem and are easily cleared up by two treatments a week apart with an insecticide for lice.
My own thoughts on the matter are that any greyhound trainer with lice on his greyhounds needs their registration revoked and a swift kick under the butt of their tail.
Mites
Of the mites that infest the dog three are of importance, 2 species of mange causing mites, Demodectic mange mites and Sarcoptic mange mites, and 1 species of ear mites.
Demodectic Mange
Demodectic mange is an inflammatory disease of the skin caused by a larger than normal population of Demodectic mites in the skin. (DEMODEX CANIS)
Most Greyhounds have some mites as part of the normal flora that live on and in the skin, and are acquired from the dam prior to weaning. It is only when there are problems with the dog’s immune system, that they multiply and invade the hair follicles by the thousands, causing inflammation and hair loss.
Demodectic mange is normally only seen in young dogs around 3 to 6 months of age and seldom in dogs older than 18 months and generally only in a small localized area. It usually affects one or two small patches around the eyes or lips and occasionally on the front legs or elsewhere on the body, and may clear up without treatment as the immune system recovers.
Treatment consists of gently rubbing in a topical Rotenone ointment to the affected area daily for 2 to 3 weeks or applying 1 ml of ECTODEX daily for 5 days and repeating the treatment after 3 or 4 days. To reduce the itchiness and allergic reaction it is advisable to also provide daily oral treatment with Prednisolone tablets.
In approximately 10% of the affected dogs the problem spreads all over the body, as a result of a genetic defect in the immune system. It is one of the most severe forms of skin diseases and can result in the death of the dog.
In the racing greyhound the treatment of the generalized form of Demodectic mange is possibly not warranted, for two reasons, (1) the treatment is difficult and not always successful and (2) because the problem is caused by a genetic defect the greyhound should not be bred with.
Examining skin scrapings under the microscope and identifying the mite involved provides the diagnosis for Demodectic mange.
Sarcoptic Mange
Sarcoptic mange is an inflammatory disease of the skin caused by SARCOPTES mites.
The mites burrow and eat their way into the skin, causing an extremely itchy, reddened scabby area with hair loss and secondary bacterial infections. It mainly affects elbows, hocks and the underside of the chest, in other words all the areas where a dog may cause some trauma to the skin by laying on contaminated concrete or nonexistent bedding; occasionally it will also affect the abdomen and earflaps.
As with other mite infestations, it is diagnosed by taking skin scrapings and examining those under a microscope.
In the case of Sarcoptic mange several scrapings may be required, as the numbers of mites causing the damage is much smaller than in Demodectic mange, making identification more difficult, however the affected area will have a distinct “mousy” odour.
Sarcoptic mange is highly contagious, and particularly in the case of pups kennelled together, it is likely that most of them will be affected.
Treatment is based on bathing the area once a week with an insecticidal shampoo or flea wash for 3 treatments and the daily application of a skin softening soothing antibacterial cream. As for other infestations that cause itchiness, oral treatment with Prednisolone is indicated.
Ear Mites
In young Greyhounds, ear mite (OTODECTES CYNOTIS) infestations can be quite common and not normally a major health problem but will require treatment as soon as the problem is noted to avoid the more serious secondary bacterial infections.
The mites are small and white and may be seen in the ear with a magnifying glass, they feed on tissue fluids and waxy secretions, the affected ear will be inflamed and showing a black sticky discharge.
Treatment involves gently cleaning the affected ear with cotton swabs moistened with warm soapy water and treatment with the appropriate eardrops 3x daily, such as OTERNA, VETIOX or VS Eardrops.
Ticks
2 species, DOG PARALYSIS TICK (IXODES HOLOCYCLUS) and the BROWN DOG TICK (RHIPICEPHALUS SANGUINEUS)
The dog paralysis tick is found in the northern warmer regions of Australia and as the name implies causes progressive paralysis starting at the hind limbs, and includes disturbed limb co-ordination, respiratory failure and if the infestation is severe enough, death of the infected animal.
The first signs that are noted are a higher pitched bark, depression and limb weakness on standing or turning quickly.
Tick species may cause anaemia as each life cycle engorges on blood, the other problem that ticks may cause is an infestation of the Protozoa that causes a disease called BABESIOSIS, and this causes severe anaemia and liver damage.
Treatment revolves around removal of the ticks and supportive treatment, and in the case of a severe infestation of the paralysis tick, treatment with an antiserum. In areas where there is a tick infestation, careful daily examination of the skin for ticks is extremely important as a preventative measure.
This includes inspecting the inside of the ears as well as between toes, with ticks having been found on the inside of the edges of the mouth.
While there are a number of products on the market designed to stop a tick from attaching themselves to the dog, they have a very limited and short term effect, and are often toxic to greyhounds. While some of the latest products designed to kill the tick as soon as it ingests blood have also not been proven to be safe to use with greyhounds.
In areas where ticks are prevalent the safest option is to ensure that grass is cut short in yards, and that there is no long grass or any bushes along fence lines where ticks can attach themselves to your greyhounds. This combined with regular grooming and careful daily examination should keep the tick problem to a minimum.