LINE OF TREATMENT OF SURRA-(trypanosomosis) IN CATTLE
Post no 1325 dt 19th of July 2019.
Compiled and shared by Dr Rajesh kumar singh, jamshedpur, jharkhand, India,
9431309542,rajeshsinghvet@gmail.com
Trypanosomosis popularly known as surra is one of the most important hemoprotozoan diseases affecting human and animal health in the tropics especially in the South East Asia & India in particular. The prevalence of surra peaks around the monsoon when the animals are under maximum work-stress owing to agricultural plantations, besides other contributing factors, viz., concurrent disease, poor nutrition, innate and acquired resistance, parasite pathogenicity, and strain of parasite. Effective surveillance for Trypanosoma evansi is constrained by a lack of sensitive diagnostic tests and information on T. evansi distribution in India. Although the level of awareness in veterinarians and diagnostic laboratories with regard to T. evansi is almost adequate, lack of diagnostic techniques of high sensitivity hinders quick identification. Microscopy is the only diagnostic tool besides animal inoculation with virtues of high specificity, ease of use, lack of cold chain . However, its low sensitivity (approximately 100,000 parasites/ml for wet blood film examination, leads to an erroneous judgment of false negativity which often results in even death of the infected individual in the absence of treatment . Only with concentration methods such as microhematocrit centrifugation , quantitative buffy coat technique , and mini-anion-exchange centrifugation technique can detect parasitemia as low as 50 parasites/ml. This limits the utility of microscopy in resource-poor settings.
It is the first trypanosome shown to be pathogenic to mammals identified by Griffith Evans a British Vet in India.
HOST———-
- Natural hosts-Camel, horse, donkey, mule, ox, goat, pig, dog, water buffalo, elephant , mongoose , deer and other wild animals like fox, hyena and tiger.
• Experimental hosts- Many laboratory animals including mouse , rat, rabbit, guinea pig and chicken.
LOCATION————
–
- Blood and lymph. The disease is called trypanosomosis.
• Name of the disease is different in different countries- most widely used is surra.
• Classical disease entity in Indian sub-continent and occurs in horses and is known as surra.
• It is a Hindi word meaning rotten (or) putrified.
• Disease in camel is called Gufar; murrina – in panama; dorrengadera in Veninzula.
• T.equinum now regarded as dyskinetoplastic strain ofT.evensi causes mal de caderes in horses in South America.
PREVALENCE -Common in Northern Africa, Asia, Northern and South America
SYMPTOMS—————-
-
High fever 41C
• Intense excitement alternative to those of severe depression (coma)
• Animals move aimlessly in circles frequently falling down, show colic, grinding of teeth, eyes staring wide open , breathing hard and noisy
• Goring against wall apparent blindness stamping of feet following groaning, micturition, profused salivation, twitching of muscles followed by partial loss of senses and prostration
• Parasitaemia due to factors unknown becomes too high; blood smears are seen with large number of parasites which occlude cerebral capillaries.
• Death may occur in 18 hr to 3 days.
• Sudden death may be mistaken for poisoning or snake bite or anthrax.
• In per acute cases death occurs in 2-3 hours. The nervous form of the disease show symptoms as above. - Sub acute and chronic
- The animals look dull, sleepy
lacrimation of eye, progressive emaciation rapid pulse
3. Intermittent fever, oedema of leg, diarrhoea and death
4. Corneal opacity – twitching of muscles below eye
5. Sub normal temp
• Progressive anaemia, weight loss and weakness.
• Abortions, infertility and stillbirth may occur in buffaloes.
• Cattle may have a chronic course with high mortality and may last up to 2 years.
• Death may occur in 2 weeks to 2 months.
• Oedematous swellings of the lower parts of the body (legs, briskets and abdomen) may be seen.
• Lymph nodes also may be swollen.
• Nervous signs like head tilt, circling, blindness, hyper-excitability, paddling movements may also be seen.
PATHOGENESIS———–
- Mainly anemia (Hemolytic Anemia).
1. This may be due to immunological mechanism resulting in haemolysis and erythrophagocytosis.
2. Trypanosome antigen attaches to RBCs and increases erythrophagocytosis.
3. Anaemia may result due to reduction in half – life of circulating cells.
4. Due to immune mechanism – enhanced haemolysis occurs; a hemolytic factor produced resulting in direct hemolysis of RBC.
5. Anemia is also associated with disorders of clotting like thrombocytopenia and disseminated intravascular clotting ( DIC).
6. Damages to blood forming organs by trypanosomes.
• Hypoglycemia
• Trypanosome absorbs glucose in blood leading to increased production of lactic acid. This leads to less intake of O2 by RBCs resulting in asphyxia. and acidosis.
• Serum potassium level is increased due to destruction of blood cells. Calcium and phosphorous ratio is disturbed.
• The lysed trypanosomes release endotoxin resulting in toxemia and death.
• Due to the anaemia, mucous membrane is pale. - Some of the clinical signs are———-
- Petechial hemorrhages and emaciation.
2. Enlargement of spleen, lymph gland and liver.
3. Congestion of mucosa of intestine, stomach, kidney and bone marrow
4. Oedema of dependant parts is common. Animal will be unable to get up.
5. Keratitis and conjunctivitis.
6. Nervous symptoms.
7. CSF section of the brain will show perivascular cuffing, infiltration meningitis and encephalitis.
CAUSE OF DEATH————–
To sum – up, death in surra is mainly due to
• High fever, toxaemia
• Anaemia – PCV is less than 25 and 30 and decreased haemoglobin
• damage of bone narrow due to trypano toxin
• Increase in erythrocyte sedimentation rate
• Hypoglycemia – reduction of blood glucose level by 30%
• Exhaustion of glycogen reserves
• Failure of liver cells to compensate the loss in glycogen reserve
Treatment and Prevention:
• Trypanocidal drugs (eg. Diminazene aceturate, 8-10mg/kg IM).
• Quinapyramine sulphate (4mg/kg).
• Quinapyramine prosalt (3-5mg /kg BW)
• Cymerlasan (0.3 to 0.6mg/ kg BW IM).
THERAPEUTIC CONCEPT OF LINE OF TREATMENT OF SURRA—
Trypanosomiases can be treated by trypanocidal drugs. In order for the drugs to be effective, early treatment is essential. The drugs can be classified as for therapeutic and prophylactic purposes. The therapeutic drugs for cattle include diminazene aceturate, homidium chloride and homidium bromide. The prophylactic drugs for cattle include homidium chloride, homidium bromide and isometamidium. Because most of these drugs have been in use for many years, many stains of trypanosomes have developed drug resistance towards these drugs. In order to try to overcome this difficulty, some countries have policies in restricting the use of drugs. Some drugs are reserved in the case of that drug resistance develops towards the drugs in use.
Tartar emetic 1.5 to 2 mg/kg in 10% saline as 2% solution to be given by slow I/V administration.Death may occur due to occlusion of dead parasites. Care must be taken not to spill over sub-cutis, otherwise cellulitis will result
• Suramin (Antrypol) 12 mg/kg as 10% solution I/V injection
• Quinapyramines used as curative and prophylactic.
o Antrycide methyl sulphate
It is soluble in water.§
It is curative at the dose rate of 3 mg /kg given as 10% solution by S/C route.§
o Antrycide chloride
It is insoluble in water and produces depot under skin. This serves as prophylactic.§
o Antrycide prosalt
It is combination of both the above salts in the ratio of 3:2 given at the dose rate of 7.4 mg/kg to be repeated after 8 weeks in fly -borne areas.§
It is available by trade name Tribexin, Triquin and the dose is 1.3 ml/kg maximum of 10 ml.§
• Diminazine(Berenil)
o It is given at @ 8-16 mg/kg B.W by deep I/M route.
o This drug is well tolerated by cattle, less tolerated by equines, camel and in dogs, general reaction occurs.
- Homeopathy Treatment :
-
1. Hyocyamus 200 : twitching of eye lids,
• Dose :One dose every hr till relief.
•
• 2. Belladonna 200 : When convulsions, nasal discharge and conjunctivitis .
• Dose :One dose every 1 hr till relief.
•
• 3. Strychinum 30 or 200 : Convulsion and twitching, salivation.
• Dose : One dose every 1 hr till relief.
•
• 4. Circuta virosa 30 or 200 : Grinding of teeth, convulsions
• Dose : One dose every one hr till relief
CONTROL – TRYPANOSOMA THEILERI
-
Surra is seasonal synchronizing with breeding of tabanid flies. So control of tabanids and bush clearing for malaria control have indirectly contributed much to decrease the incidence of tryps.
• Chemotherapy of ailing and susceptible animal.
• Destruction of reservoir host (or) game animals.
• Chemoprophylaxis in horse 2-4 months with Antrycide prosalt at 5 mg /kg.
• Breeding trypanotolerant breeds like – N’dama cattle.
• Quarantine measures.
• Control measures:
Trypanosomiasis can be prevented by the use of prophylactic drugs. The prophylactic drugs currently used for cattle are homidium and isometamidium. After properly injecting into the animals, these drugs can usually provide three months protection. Prophylactic drugs are very effective to be used to protect animals at times when they are exposed to constant disease challenge. Unfortunately, because these drugs have been in use for many years and in many places they were not properly used, resistance has been developed in some places. Another effective control method is to eradicate the vectors, tsetse flies, which transmit the disease. Various strategies have been used to control tsetse flies. These include spraying insecticide on tsetse habitat, destruction of tsetse habitat and alteration of vegetation so that it becomes not suitable for tsetse flies.
