Diseases of commercial waterfowl Flashcards
List 4 viral diseases of Ducks
Duck viral hepatitis
Duck viral enteritis
Newcastle disease virus
Avian influenza
List some bacterial diseases of ducks
E.coli
Pasteurella multicidia
Erysipelas
Salmonella
Staphylococci
Chlamydia
What type of virus is duck viral hepatitis?
Picornavirus
Which ages of ducks are most affected by duck viral hepatitis?
- Highly infectious in ducklings, acute onset
- Most affecting ages of 2 days to 3 weeks old
- Adults birds are immune to infection, 7+ weeks completely immune
Describe the spread of Duck viral hepatitis
- Entry into birds by ingestion
- Contaminated people, vehicles, equipment and other farm materials could spread the virus
- NO vertical transmission
- High morbidity within susceptible birds
What are the clinical signs of duck viral hepatitis?
- Picornavirus strain causes death within 1 hour
- Opisthotonus (dramatic abnormal posture)
List three DDx for duck viral hepatitis
Bacterial septicaemia
Duck Viral enteritis
Mycotoxicosis
Describe the pathological lesions caused by duck viral enteritis
- Hepatomegaly, petechial haemorrhages
- Fatty kidneys
- Septicaemic carcass
How is duck viral enteritis controlled?
Breeders – live and inactivated vaccines
Ducklings – live vaccination
Biosecurity and Management measures
Duck viral enteritis is what type of virus?
Herpes virus
Name the two hosts of duck viral enteritis
Ducks
Geese
Which birds are most susceptible to duck viral enteritis?
Breeding birds
How is duck viral enteritis spread?
- Presence of water essential
- Oral and cloacal routes
- Wild waterfowls can spread to domestic ducks
- Latency has been reported, virus shed for many years
What are the clinical signs of duck viral enteritis?
Ataxia
Eye discharge, pasty eyelids
Nasal discharge
Diarrhoea – water with blood, vent blood stained
Photophobia
Normally body condition good
Describe the lesions caused by duck viral enteritis
- Multiple haemorrhage in tissues
- Free blood in body cavity – particularly abdomen
- Petechial haemorrhages on visceral organs
- Haemorrhage on oesophageal mucosa, other GIT
- Necrotic foci on liver and oesophagus
How is duck viral enteritis diagnosed?
- History, clinical signs and lesions, eg. significant drop in egg production
- Virus isolation confirmatory
- PCR
How is duck viral enteritis controlled?
- Biosecurity
- Avoid contact with wild birds
- Vaccination
Describe the signs of avian influenza in waterfowl in the UK
- Small increase in mortality
- Drop in egg production, little slowly to 30%
- Decreased in feed and water consumption
- Little subdued
Describe Newcastle disease in ducks
- Ducks are relatively resistant to NDV
- Common problem – major drop in egg production
- No clinical signs in younger birds
- Vaccination works well
Describe E.coli infections in ducks
- Mostly from environment
- 1-8 weeks old young birds susceptible
- Egg peritonitis in laying birds
How are E.coli infections in ducks diagnosed?
history, clinical signs, necropsy, laboratory support
How are E.coli infections in ducks treated/prevented?
Treatment – antibiotics
Prevention
- Hygiene and sanitation
- Management
- Vaccinate breeders
Riemerella anatipestifer causes what lesions in the body?
Polyserositis, exudates and fibrin covering visceral organs, cavity
Lymphoid necrosis of the white pulp of spleen
What is polyserositis?
Inflammation and effusion of the pericardium, pleura or peritoneum
Describe salmonella infections in ducks
Little clinical signs
Infrequent mortality 0-7 days-old
Vertical and horizontal transmission
How are salmonella infections in ducks treated/prevented?
- Live and inactivated vaccines
- Antibiotics
- Competitive exclusion
- Hygiene and sanitation, biosecurity at breeding farm and hatchery important
Describe Chlamydia infections in ducks, including clinical signs
All ages can be affected
C psittaci - zoonotic
Clinical signs – conjunctivitis, anorexia, ruffled feathers
How are chlamydia infections in ducks treated/prevented?
No vaccine available
Antibiotics
Hygiene and sanitation, biosecurity at breeding farm and hatchery important
What is the source of Aspergillosis fumigatus?
Contaminated environment – litter, feed
What are the clinical signs of Aspergillosis fumigatus in ducks?
Gasping, weight loss, anorexia, death
Stress exacerbates susceptibility and disease
How is Aspergillus fumigatus treated/prevented?
Use of fresh bedding materials
Anti-fungal, in-feed
Hygiene and sanitation, biosecurity at breeding farm and hatchery important
