Haemoprotozoan of Dairy Animals

This article is beneficial for both veterinarian and for livestock owners, because if farmer can judge the abnormalities in behaviour of animal, only then he/she will be able to recognise the sick animal and be able to call the doctor for treatment. And I will tell very practical clinical signs in different species of dairy animals for veterinarian by seeing those clinical signs he/she can collect the blood sample for laboratory diagnosis, and be able to give some first aid until the lab report is not received. Article is on haemoprotozoan (blood parasites) of dairy animals (cow, & buffalo) These are of two types:

• Intra-erythrocytic ,or live in RBC’S eg: Anaplasma, Theileria or Babesia.
• Extra-erythrocytic or live outside the RBC’S eg: Trypanosomes

Transmission
Also known as tick born diseases, haemoparasites are transmitted from one animal to other animals through ticks, flies. Also transmitted mechanically by blood transfusion, infected surgical instruments or when we do not change the needle during vaccination.

Clinical signs
These haemoprotozoan diseases are seasonal; commonly affect the animals in warm and humid weather when there is lot of tick population.

Common clinical sign which are present in all hemoprotozoan

1. High fever
2. Anaemia
3. History of ticks on animal body.

Apart from common clinical signs there are certain specific signs of each haemoprotozoan disease

Intra- erythrocytic haemoprotozoan

Anaplasmosis
Also know as gall sickness caused by Anaplasma marginale (more pathogenic) and Anaplasma centrale (less pathogenic). The clinical signs are usually very mild in calves below 6 month of age,cattle upto 3 years develop typical and fatal disease, above 3 years disease is per acute and more fatal , infected cattle became carrier of anaplasmosis but are generally immune for further infection. (Handbook on Infectious Animal Diseases Shukriti Sharma, Vishal Mahajan & Kulbir Singh Sandhu 2008 Edition page no 103 )

Clinical signs: Very typical clinical signs of Anaplasmosis are:

• Difficulty in breathing due to exertion, mild coughing and there is open mouth breathing, this is due to anaemia.
• All mucous membranes become pale or yellow rather than healthy pink, we can check from eyes and vulva mucous membrane.
• Constipated faeces due to intestinal stasis and the faeces are coated with mucous membrane
• Staggering gait of animal
• Fever is recurrent (it is not throughout the day), either in the morning or in the evening with rapid bounding pulse.

Post mortem lesion or findings: when we open the body of dead animal there is jaundiced appearance of all visceral organs, enlarged gall bladder, and fatty liver.

Babesiosis or Red water disease
It is vector born disease. Major vector for Babesia bigemina is Rihipicephalus microplus. Haemoprotozoan are pear shaped piroplasm joined at acute angle and present in the RBC’S.

Clinical signs: Apart from high fever and anaemia there is destruction of large number erythrocytes by piroplasm of Babesia resulting in haemoglobinemia and consequently haemoglobinuria,increased respiratory rate, may be diarrhoea or constipation pregnant animal my abort and death due the heavy loss of blood .

Post mortem lesions or findings: Most diagnostic lesion is urinary bladder filled with coffee coloured urine, gall bladder filled with thick granular bile.

Theileriasis in dairy animals
It is also a tick born disease of cattle characterised by high fever and anaemia. Theileria anulata and Theileria parva are two organism causing disease. Theileria ovis is causing Theileriasis in goats. Theileriasis is mainly disease of exotic cattle.

Transmission: Rhipicephalus spp. of tick is responsible for transmission of disease from one animal to other animal. The mechanical transmission is not of much importance. After the bite the schizoints move into the lymphocytes and cause lymphadenopathy and then piroplasm of Theileria in erythrocytes.

Clinical signs: Lymphadenopathy, (inflammation of parotid lymph node in calves along with lacrimation, if not taken care leads to corneal opacity, and there is diarrhoea having blood . Inflammation of pre scapular and pre femoral lymph node along with diarrhoea having blood in adult animals is very typical clinical sign of subclinical Theileriasis. There is difficult respiration in animals (this is due to cystic mediastinal lymph node located in between the lung lobes). In clinical Theileriasis there is fever and anaemia, recumbency followed by death .There is cerebral form of Theileriasis in which animals exhibit circular movements, head pressing, salivation.

Post-mortem lesions and findings: very clear sign is cystic mediastinal lymph node and punched necrotic ulcers in the abomasum.

Extra erythrocytic protozoan

Trypanosomasis
It is also a vector born disease of dairy animals .Caused by Trypanosome evansi. Protozoan is present outside the RBC’S. Incidence of trypanosomiasis is high in rainy season due to large number of biting flies.

Transmission: Trypanosoma evansi is transmitted by biting flies/Tabanus/Glossina flies.

Clinical signs: In per acute form of disease animal dies after showing convulsions. (this is because of hypoglycaemia) high fever ,normocytic normochromic anaemia due to destruction of erythrocytes by flagellar action of parasites (Handbook of infectious animal diseases by Shukriti Sharma, Vishal Mahajan and K.S Sandhu 2008 edition page no 273), head pressing , intermittent fever, gazing of eyes, frequent micturition, corneal opacity unilateral or bilateral ,staggering gate and circling movement, wasting of muscles .

Post-mortem lesions and findings: all organs are anaemic, serous fluid in pericardial sac and abdominal cavity.

Diagnosis of haemoprotozoan diseases

Diagnosis of haemoprotozan diseases is based on clinical signs and laboratory diagnosis

Precautions while collecting samples for laboratory diagnosis

1. Always collect blood sample when there is fever
2. In case of Trypanosomias is always give dextrose saline to animal solution before collecting the sample, and collect blood from ear vein.
3. For the diagnosis of Theileriasis collect lymph node aspirate ( hold the lymph node ,inject 4-5 ml of normal saline solution ,do not withdraw the needle ,just massage the lymph node and try to retract back the injected saline solution. Make on the spot smear of this lymph node aspirate, dry it and fix it with methanol. Or you can send aspirate in syringe as early as possible to laboratory.
4. Send blood in EDTA vacutanior. Try to send as early as possible.

Few tips for laboratory person

1. Mix the blood before making smear.
2. Try to make very thin smear.
3. Always airs dry the blood smear,
4. Fix the slide properly.
5. Use distilled water for diluting Giemsa stain.
6. Field A & Field B stain are very good for staining slides for haemoprotozoan.

Take a small drop of blood ,put on grease free slide ,make thin smear ,dry in air ,put leishman’s stain for 1 min,wash the slide,put feild B stain for 30 sec, wash with water,put feild A stain for 1 min. Wash with water and dry in air . Examine the slide under 100x power of microscope .

Diffrential diagnosis

1. From all diseases having high fever and anaemia.
2. When there are nervous signs in case of Theileriasis, we should not confuse it with trypanosomiasis, confirmation by blood smear examination.
3. Respiratory signs in Theileriasis should not be confuse with Heamorrhagic.
4. After checking slide or after checking CBC it is very clear that there is anaemia with lymphocytocis in theileriasis but in case of H.S. there is neutrophelia.
5. In Babesisosis haemoglobin urea, check the history of parturation (postparturient haemoglobinurea, respond to phosphorus therapy) and braken fern poisoning( history of ingestion of fern), leptospirosis confermation by PCR .

Treatment: It is strongly recommended to all farmers and veterinarians, never treat animals those are suspected for haemoprotozoan without laboratory diagnosis. Always try to give specific treatment to avoid drug resistance and burden on the pocket of the livestok owner. Sometime there is mix infection, like anaplasmosis and theileriasis most of the time ,but from clinical signs we are not able to judge clearly, which treatment is to be given. After taking blood sample we can give suportive treatment like, antipyretic ,dextrose saline etc. After looking the laboratory report specific treatment can be started

Anaplasmosis
Injection oxytetracycline 100ml in normal saline i/v for three days. If there is reoccurance or carrior state of disease then give oxytetracycline LA 20 mg /kg body wt i/m. repeat after 1 wk. Imidocarb is highly effective against anaplasma marginale a single injection @1.5 mg/kg s/c (The Merck Veterinary Manual 8^th Edition Page no 23) suportive treatment with antipyretic, haemetinic syrup .

Theileriasis
Subclinical theileriasis: When blood picture shows only koch’s blue bodies in lymphoblasts and cbc shows lymphocytosis and there is no fever and anaemia we should treat the animal with schizonticidal drug lactate salt of halofuginone @1.2-2.0 mg/kg body weight orally for two days , or we can give injection of oxytetracycline –LA @20 mg /kg body weight i/m. (Handbook of infectious animal diseases by Shukriti Sharma ,Vishal Mahajan and K.S Sandhu 2008 edition page no260-261)

Clinical Theileriasis: when there is high fever with anaemia and blood pictuer shows piroplasms of Theileria anulata we should traeat the animal with buparvaquone(butalex) @2.5 mg/kg body weight i/m repeat after 48 hours. Suportive therapy is must like antipyretic and haematinics.

Trypanosomiasis
Many drugs are used to treat trypanosomiasis in dairy animals. Quinapyramine sulfate @ 5 mg/kg body weight s/c is used for treatment.and combination of quinapyramine sulfate and chloride are used for prophylactic and treatment @7.4 mg/kg body wt. (Handbook of infectious animal diseases by Shukriti Sharma ,Vishal Mahajan and K.S Sandhu 2008 edition page no 275). There is hypoglycaemia in animals so give dextrose saline i/v injections and other suportive treatment

Babesiosis
Injection diminazene aceturate is given i/m @ 3-5 mg/kg body weight. (Injection imidocarb dipropionate s/c injection @1.2 mg/kg body weight (The Merck Veterinary Manual 8^th Edition Page no.25) suportive treatment with antipyretic and haemup syrups .

Controle of haemoprotozoan
Effective control of haemoprotozoan diseases is with control of ticks both on animals and in sheds , 80% of ticks live in sheds in groves of walls and floor of sheds and 20% of ticks on animal body . to kill ticks on body of animals apply drugs like amitraj pour on or butox. we can dipp the animal also when more number of ticks on the body of animals . we can also use injection ivermectin @ dose of 1 ml /33 kg body weigt s/c.

For control of ticks in sheds
1. Burning of sheds with hot air. 2. spray with malathion 0.5%.

For control of flies like tabnid flies
These flies develop in warm and damp places, therefore spray with kerosene oil or turpentine oil to kill the aquatic larvae. The manure should be frequently removed from sheds.

All slides are prepaired, examined and diagnosed by Dr Parvinder kaur, Veterinary Officer NRDDL, Jalandhar Punjab

Refrence:

1. The Merck Veterinary Manual 8^th Edition .
2. Handbook of Infectious Animal Diseases by Shukriti Sharma ,Vishal Mahajan and K.S Sandhu 2008