Salmonella infections of poultry (other common poultry dx / control stratergies)

What are the important foodborne strains of salmonella?

• Salmonella Typhimurium (ST)

• Salmonella Enteritidis (SE)

What are the two other important strains of salmonella?

• Fowl Typhoid (S. gallinarum)

• Pullorum disease (S. pullorum)

Which birds are more susceptable to salmonella?

Young chicks

What are the clinical signs associated with salmonella (general)?

• Anorexia

• Dullness

• Dehydration

• Retarded growth

What are the clinical signs associated with salmonella in complicated severe cases?

• Ascites

  

What are the lesions associated with salmonella in poultry?

• Enteritis

• Focal necrotic lesions in the mucosa of small intestines

• Caecal cores

• Inflammation of the spleen, liver and kidney.

Why is salmonella of public health importance?

• Causes gastroenteritis, nausea, V+, D+ and fever in humans

• Transmission critical for infants, children & immunocompromised populations

How is salmonella controlled at the farm level?

• Biosecurity —> Sanitation/disinfectants, rodent control etc.

• Vaccination

• Minimise stress

• Surveillance and corrective measures (eg. Culling) —> Testing at intervals

• Probiotics, competitive exclusion products

• Feed supply (Quality and microbiology)

• Removal of dead birds

What type of production system is best used?

• All in all out

• Thinning at intervals

What is important to consider with live salmonella vaccinations?

Detection methods are able to differentiate the vaccine strains from wild strains

What are the different areas of control at consumer level?

• Shops & supermarkets

• Restaurants

• Home-consumers

  • Storage

  • Handling

  • Proper cooking

What is an important parasitic disease in birds?

Coccidiosis —> Eimeria

• E. aacervulina

• E. brunetti

• E. maxima

• E. mitis

• E. necatrix

• E. preacox

• E. tenella

How do you diagnose coccidiosis?

• Farm history

• Clinical examination

• Sampling the feed

• Post-mortem examination

• Microscopic examination

How do you control coccidiosis?

• Biosecurity

• Management

  • Density

  • Hygiene & sanitation

What are the internal protozoal parasites that affect birds?

• Histomonosis (Blackhead) —> H. gallinarum intermediate host

• Trichomonosis (cancker)

• Hexamitosis

What does histomonosis cause?

Yellow D+, fatality if not attended early

How do you prevent trichomonosis?

• Worm regularly & cider vinegar ( 7 days/month) d/water

• Probiotics

What are the important mites in poultry?

• Northern fowl mite (Ornithonyssus sylviarum)

  

• Common red chicken mite (Dermanyssus gallinae)

What are the different ways you can use parasite control?

• Protect the birds/flocks

• Treat the hideaways

What are the internal parasites of poultry?

What is a parasite that is a differential for Infectious Laryngotracheitis?

Gapeworm (syngamus trachea) —> respiratory problem due to haemorrhage

What is the licenced worming drug in poultry?

• Flubendazole —> licensed wormer

• In food for 7 days

What does Hexamitosis cause?

Diarrhoea and unthriftiness

What are the different routes of infection in the farm?

• Wild birds/ animals

• Chicken hospital —> within farm

• Multi-age flocks

• Suppliers

• Human workers/visitors

• Poor biosecurity and hygiene

What are some examples of strategic medications?

• Anti-coccidials

• Health protectors

  • Herbal eg. Oregano

  • Propionic acids

• Anti-helminthics

What are the different reasons for the use of vaccinations?

• Disease incidence, severity or to reduce carcass condemnation

• Mortality

• LBW or FCR

• Drop in egg production/quality

• Drop in fertility/hatchability

What are the different routes of administration of vaccinatons?

• Coarse spray —> e.g. live respiratory vaccines

  • Vaccine is inhaled or pecked off the feathers

• Drinking water —> e.g. live respiratory, coccidial, salmonella

  • nipple drinkers (chicks) / bell drinkers

• On-food —> e.g. live coccidial

• Injection —> e.g. SC – live Marek’s & SC or IM mostly killed vaccines

• In-ovo —> eg. Marek’s disease (live - only live one given this way)

  • embryo bathed in vaccine —> immune response begins early

What are the different ways course sprays are delivered?

What is the process of vaccinating in the drinking water effectively?

• Withdraw water to make birds thirsty

• Make up vaccine in tank, allow to run through lines —> check with blue dye

• Allow birds to drink

• Ensure sufficient drinkers

• Check that birds actually drank – blue dye on their bodies

What are the features of killed vaccines?

• Given before Coming into lay(16-18 wks)

• Following a live primer in many cases e.g., IB, ART

• Always include adjuvants

When is an in ovo vaccination carried out?

18 days of incubation

Why could you have vaccination failure?

• Host factors —> inappropriate age, immunosuppression

• Environment —> temp, ventilation

• Agent —> wrong strain, storage, dilution, admin

• Monitoring