Understanding the enteritis syndrome – a guide to diagnosis

Understanding the enteritis syndrome – a guide to diagnosis

viruses nutrition cocci The Enteritis Syndrome Bacterial Enteritis Clostridium perfringens Dysbacteriosis/non-specific bacterial enteritis Clostridial enteritis Cholangiohepatitis Necrotic enteritis

Enteritisisagrowingproblemworldwide Particularly in flocks where: • Cocci vaccines are used • Antibiotic digestive enhancers have been removed • Medication withdrawal times have been extended • Wheat-based diets are fed

Economic and performance impact of enteritis • Feed conversion: 4-10 point decline • Live weight: reduced 30-120g/bird • Mortality: increased 1-5% • Condemnations: increased up to 10% • The performance impact occurs at subclinical levels • The cost of enteritis is estimated at at US$0.05/bird or more

Enteritisis not a single disease Two different causes lead to three forms: • Clostridium perfringens • Clostridial enteritis/necrotic enteritis • Cholangiohepatitis • Non-specific bacterial enteritis • not necessarily associated with C. perfringens • results in dysbacteriosis

Enteritisis not a single disease Accurate diagnosis is necessary for effective treatment, because each form requires a specific treatment protocol.

1. Clostridial enteritis/Necrotic enteritis Disease of the small intestine associated with proliferation of C. perfringens causing mortality and diarrhoea. Costly sub-clinical form often goes undiagnosed. Economic losses begin early, before mortality is seen. Medication protocol: Strategically medicate with antibiotic effective against C. perfringens

Cholangiohepatitis Clostridial infection affecting the liver, leading to enlargement, fibrosis and often jaundice, with condemnations at processing. Medication protocol: Strategically medicate with antibiotic effective against C. perfringens

Dysbacteriosis Presence of abnormal flora in the small intestine that causes diarrhoea and/or malabsorption but does not increase mortality. Not usually associated with C. perfringens. Medication protocol: Treat immediatelywhen observed. Consider using litterbox to detect wet droppings early. Strategic preventive therapy may not work.

viruses nutrition cocci Enteritis Intestinal bacterial overgrowth Clostridium perfringens Dysbacteriosis/non specific bacterial enteritis Clostridial enteritis Cholangiohepatitis Necrotic enteritis

The classical signs of necrotic enteritis Elevated mortality with intestinal necrosis

Other possible signs Wet litter, feed passage and diarrhoea:Is it enteritis?

Diagnosis You are presented with the following clinical signs • Wet litter, diarrhoea • Feed passage • Elevated mortality ? • Increased condemnations ? Examine sacrificed and dead birds

Is it Coccidiosis? Score 4 • Eimeria acervulina • Eimeria maxima Use microscopic examination to confirm or eliminate Eimeria maxima infection

Is it clostridial enteritis? Score 4 Severe and extensive necrosis typical of field cases: classic necrotic enteritis

Diagnosis Clostridial enteritis Post-mortem: • Intestinal necrosis • Clinical signs: • Occurs at 15-25 days • the birds stop growing • mortality • diarrhoea • huddling • depression • rough feathers

Is it clostridial enteritis? Score 3 Larger patches of necrosis

Is it clostridial enteritis? Score 2 Focal necrosis or ulceration Erosions can be removed by gently scraping with a scalpel blade, This is not the case for Eimeria acervulina

What diagnosis do you give this? Score 1 Thin-walled or friable small intestine If this is your only finding and there are no enteritis scores of 2, 3, or 4

Consider a diagnosis of Dysbacteriosis Post mortem: • Intestinal inflammation • Watery intestinal contents • Orange mucus in jejunum • Clinical: • Sticky droppings • Wet litter • Sometimes foamy caecal droppings • Reduced feed intake • Reduced physical activity • Normal or increased water intake • Normal mortality • Selective feeding behaviour • may be observed

Is it Dysbacteriosis? To confirm diagnosis: • Use Plates • Treat with antibiotic, monitor results • Does condition resolve with treatment?

Yes: Continue antibiotic treatment. • To get the best results treatment should be initiated as early as possible • No: Enteritis not related to cocci or bacterial overgrowth • Viruses • Feed issues, • e.g. mycotoxins, fat quality, • biogenic amines

Understanding the enteritis syndrome – a guide to diagnosis