Swine Dysentery:

• It is muco hemorrhagic diarrheal disease of pigs that affects large intestine.
• It is characterized by bloody to mucoid diarrhea and severe dehydration.
• It is most often observed in growing-finishing pigs and associated with reduced growth performance and variable mortality.

Etiology:

• Brachyspira hyodysenteria
• These spirochetes consistently produce strong β-hemolysis
• Gram-ve, helically coiled, oxygen tolerant, anerobic spirochete.

Transmission:

• Ingestion of infected feces
• Transmission can also occur through birds, flies, and fomites.
• Infected mice on premise may also be source of infection.
• Contaminated lagoon water and contaminated vehicles are important source of transmission.

Pathogenesis:

• Disease has got incubation period of 5-21 days
• Organism reaches to large intestine where it colonizes, proliferates and penetrates mucosal layer
• Bacteria produce toxins and hemolysin which cause tissue destruction and ultimately to mucohemorrhagic colitis.

Clinical Signs:

• Diarrhea; usually grey-yellow color, mucoid feces
• Diarrhea continues to become mucohemorrhagic with excess mucus and fresh blood apparent and moderate fever.
• Slightly depressed with reduced appetite.
• Skin discoloration in terminal stages
• Perineal area may be blood stained.
• Sunken eyes, marked weakness, hollow flanks
• Sudden death

PM Findings:

• Lesion are restricted to colon and cecum.
• Mesentery and serosa are edematous
• Large intestine is heavy, thick walled, congested and edematous
• Mucosa covered with fibrin, necrotic debris and mucus.
• Serosal hyperemia

Diagnosis:

• Based on clinical findings
• Based on PM findings
• Demonstration of spirochetes in stained smear made from colonic scrapping
• Serological test: ELISA

Treatment:

• Tiamulin @10-15 mg/kg, b.wt. IM x SD
• Carbadox @ 50mg/kg, of feed for 30 days
• Carbadox combined with sulfamethazine @100 mg/kg, of feed for 30 days
• Lincomycin @ 11mg/kg, b.wt. IM, OD, for 5-7 days

Control Measures:

• Strict quarantine measures should be followed.
• Biosecurity measures such as restriction of movement of vehicles, animals, humans onto farms.
• Disinfection of farm premises with suitable disinfectant; sodium hypochlorite, iodophores.
• Mass medication and sanitation program should be followed.