Vocabulary: Translate The Following Words Into Vietnamese And Learn By Heart Them. 84468

G H I

J K L

M N O

Exercise 2: Match the words in column A with their definitions in column B.

1. Distemper

2. Cataract

3. Pneumonia

4. Ringworm

5. Rabies

6. Erysipelas

7. Bacillus

8. Anthrax

9. Glanders

10. Tetanus

A. Disease of sheep and cattle transmissible to humans.

B. Inflammation of one or both lungs

C. Disease causing fever and a deep red inflammation of the skin.

D. Contagious viral disease of esp. dogs, transmissible through saliva to humans etc. and causing madness; hydrophobia.

E. Bacterial disease causing painful spasm of the voluntary muscles.

F. Rod-shaped bacterium, esp. one causing disease.

G. Eye condition in which the lens becomes progressively opaque.

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H. Contagious disease of horse.

I. Disease of esp. dogs, with coughing and weakness.

J. Fungal skin infection causing circular inflamed patches, esp, on the scalp.

Chapter 5

CLASSICAL SWINE FEVER (Hog Cholera) MH38 - 05

In this Chapter

Objectives:

By the end of the Chapter, learners are able to

Study aetiology, epidemiology, diagnosis, prevention and control of Classical Swine Fever (Hog Cholera).

Know this disease which we can treat or can’t.

1. Vocabulary: Translate the following words into Vietnamese and learn by heart them.

Aetiology (n) = etiology :

Disinfectant (n) :

Epidemiology (n) :

Transmission (n) :

Spread (v) :

Infection (n) :

Secretion (n) :

Excretion (n) :

Conjunctiva (n) :

Insemination (n) :

Diagnosis (n) :

Incubation (n) :

Hyperaemia (n) :

Haemorrhagic (adj) :

Mortality (n) :

Encephalomyelitis (n) :

Hypoplasia (n) :

Salmonellosis (n) :

Immunofluorescence (n) :

Immunoperoxidase (n) :

Treatment (n) :

Veterinary Practitioners (n) : Quarantine (n) :

Sterilization (n) :

Medical prophylaxis (n) :

Enzootic (adj) :

Eradication (n) :

Vaccination (n) :

Slaughter (n) :

Disinfection (n) :

Investigation (n) :

2. Reading: Read the following text and do the exercises that follow.

CLASSICAL SWINE FEVER (Hog Cholera)

http://www.oie.int/ Office International des Epizooties.

AetiologyEpidemiologyDiagnosisPrevention and control

2.1. AETIOLOGY

Classification of the causative agent

Virus Family Flaviviridae, genus Pestivirus Resistance to physical and chemical action

Temperature: Partially resistant to moderate heat (56ºC) pH: Inactivated by pH<3.0 or pH>11.0

Chemicals: Susceptible to ether, chloroform, ß-propiolactone 0.4%

Disinfectants: Inactivated by cresol, sodium hydroxide (2%), formalin (1%), sodium carbonate (4% anhydrous or 10% crystalline, with 0.1% detergent), ionic and non-ionic detergents, strong iodophors (1%) in phosphoric acid

Survival: Survives well in cold conditions and can survive some forms of meat processing (curing and smoking)

2.2. EPIDEMIOLOGY

Hosts

Pigs and wild boar are the only natural reservoir of classical swine fever

virus

Transmission

 Direct contact between animals (secretions, excretions,semen, blood)

 Spread by farm visitors, veterinarians, pig traders

 Indirect contact through premises, implements, vehicles, clothes, instruments and needles

 Insufficiently cooked waste food fed to pigs

 Transplacental infection

Sources of virus

 Blood and all the tissues, secretions and excretions of sick and dead animals

 Congenitally infected piglets are persistently viraemic and may shed the virus for months

 Infection routes are: ingestion, contact with the conjunctiva, the mucous membranes, skin abrasions, insemination, percutaneous blood transfer

Occurrence

The disease occurs in much of Asia, Central and South America, and parts of Europe and Africa. Many countries are free of the disease

For detailed information on occurrence, see recent issues of World Animal Health and the OIE Bulletin

2.3. DIAGNOSIS

Incubation period is 2-14 days Clinical diagnosis

Acute form

 Fever (41ºC), anorexia, lethargy

 Multifocal hyperaemia and haemorrhagic lesions of the skin, conjunctivitis

 Cyanosis of the skin especially of extremities (ears, limbs, tail, snout)

 Transient constipation followed by diarrhoea

 Vomiting (occasional)

 Dyspnoea, coughing

 Ataxia, paresis and convulsion

 Pigs huddle together

 Death occurs 5-15 days after onset of illness

 Mortality in young pigs can approach 100% Chronic form

Fig 5.1 Larynx of pig with swine fever, note haemorrhaging (red and dark black areas)

 Dullness, capricious appetite, pyrexia, diarrhoea for up to 1 month

 Apparent recovery with eventual relapse and death Congenital form

 Congenital tremor, weakness

 Runting, poor growth over a period of weeks or months leading to death

 Clinically normal but persistently viraemic pigs, with no antibody response Mild form (sows)

 Transient pyrexia and inappetence

 Fetal death, resorption, mummification, stillbirth

 Birth of live, congenitally affected piglets

 Abortion (rare)

Fig 5.2 Kidneys showing small pinpoint heammorrahges.

Lesions Acute form

 Leucopaenia and thrombocytopaenia

 Widespread petechiae and ecchymoses, especially in the skin, lymph nodes, larynx, bladder, kidney, ileocaecal junction

 Multifocal infarction of the margin of the spleen is characteristic but not always present

 Enlarged haemorrhagic lymph nodes are common

 Encephalomyelitis with perivascular cuffing Chronic form

 Button ulcers in the caecum and large intestine

 Generalised depletion of lymphoid tissue

 Haemorrhagic and inflammatory lesions are often absent Congenital form

 Central dysmyelinogenesis, cerebellar hypoplasia, microencephaly, pulmonary hypoplasia, hydrops and other malformations

Differential diagnosis

 African swine fever (indistinguishable clinico-pathologically.It is essential to send samples for laboratory examination)

Fig 5.3 Haemmorrhaging inside chest cavity.

 Infection with bovine viral diarrhoea virus

 Salmonellosis

 Erysipelas

 Acute pasteurellosis

 Other viral encephalomyeliotis

 Streptococcosis

 Leptospirosis

 Coumarin poisoning

Laboratory diagnosis Procedures

For details, refer to the OIE Manual Identification of the agent

 Direct immunofluorescence test on cryostat sections of organs from affected pigs

 Virus isolation in cell culture, with virus detection by immunofluorescence or immunoperoxidase. Confirmatory identification with monoclonal antibodies

Serological tests

 Neutralisation peroxidase-linked assay

 Fluorescent antibody virus neutralisation

 ELISA (prescribed tests in the Manual) Samples

Identification of the agent

 Tonsil

 Lymph nodes (pharyngeal, mesenteric) kept under refrigeration and shipped to laboratory as quickly as possible

 Spleen

 Kidney

 Distal ileum

 Blood in EDTA (live cases)

Serological tests

Fig 5.4 Haemorrhaging in bladder of pig with swine fever

 Serum samples from suspect recovered animals, from sows with suspected congenitally infected litters, or from pigs under surveillance

2.4. PREVENTION AND CONTROL

No treatment is possible. Affected pigs must be slaughtered and the carcasses buried or incinerated

Sanitary prophylaxis

 Effective communication between veterinary authorities, veterinary practitioners and pig farmers

 Effective disease reporting system

 Strict import policy for live pigs, and fresh and cured pig meat

 Quarantine of pigs before admission into herd

 Efficient sterilization (or prohibition) of waste food fed to pigs

 Efficient control of rendering plants

 Structured serological surveillance targeted to breeding sows and boars

 Effective pig identification and recording system Medical prophylaxis

Vaccination with modified live virus strains is effective in preventing losses in countries where classical swine fever is enzootic, but is unlikely, on its own, to eliminate infection entirely. In countries which are free of disease, or where eradication is in progress, vaccination is normally prohibited

Response to outbreaks

 Slaughter of all pigs on affected farms

 Disposal of carcasses, bedding, etc.

 Thorough disinfection

 Designation of infected zone, with control of pig movements

 Detailed epidemiological investigation, with tracing of possible sources (up- stream) and possible spread (down-stream) of infection

 Surveillance of infected zone, and surrounding area

References and Other Information.

o Reference experts and laboratories.

o Classified as an OIE List Adisease (A130)

o Chapter 2.1.13. in the Manual of standards for Diagnostic Tests and Vaccines.

o International Animal Health Code

+ Other references – see the Index

o World Animal Health and the OIE Bulletin.

o Current Animal Health Status (disease Information).