Clostridial Diseases Flashcards
What causes blackleg? What animals are most commonly affected?
Clostridium chauvoei
mainly cattle between 6 months to 2 years of age + sheep due to a wound or postparturition
What is the transmission of blackleg like?
- endospores of C. chauvoei are ingested and cross the GI tract into the bloodstream
- endospores are deposited throughout the body or enter through a wound
- bacteria become activated and multiply in an anaerobic environment, particularly bruised or damaged muscle (most commonly occurring during transport, handling, injection, or rough activity)
What is the classic clinical sign indicative of blackleg? What else is commonly observed?
swelling with possible palpable crepitus from gas bubbles
- lameness
- fever
- depression
- anorexia
- rapid death without signs of illness, usually within 12-48 hours
How is blackleg diagnosed? What is seen postmortem?
presumptive diagnosis based on gaseous swelling in a young animal
infected area is black and necrotic with gas bubbles –> foul, sweet odor resembling rancid butte is commonly present
What treatment is recommended for cases of blackleg? What are 2 options of prevention?
Penicillin –> requires early identification and survivors may have permanent deformities
- immediately dispose carcasses without contaminating the environment
- 7-way bacterin vaccine: 2 doses at one month intervals
What are the contents of the 7-way clostridial bacterin vaccine?
- C. chauvoei
- C. septicum
- C. novyi A
- C. novyi B
- C. sordellii
- C. perfingens C
- C. perfringens D
What animals are affected by malignant edema? How does this disease develop?
cattle, sheep, goats, and horses of any age
an open wound is infected with the bacteria –> injury, castration, difficult parturition, fighting, etc.
What is bighead?
form of malignant edema in sheep caused by Clostridium novyi type A
What clinical signs are indicative of malignant edema?
- localized swelling and edema that may gravitate to dependent portions of the wound
- depression, anorexia, high fever
- death often occurs within 24-48 hours
How is malignant edema diagnosed?
postmortem = infected area is darkened with a foul odor, there is swelling WITHOUT gas accumulation
How is malignant edema treated? How is it prevented?
Penicillin –> requires early identification
- vaccination with 7-way bacterin vaccine
- clean surgery
- clean environment following a surgical procedure
What causes redwater disease?
Clostridium haemolyticum
do not confuse with other conditions referred to as Redwater, including Babesiosis
What animals are most commonly affected by Redwater disease? What is transmission like?
cattle and sheep
- endospores are ingested and bacteria lodge in the liver
- when damage occurs to the liver (most commonly caused by liver fluke, Fasciola hepatic), the bacteria replicates
- toxin released results in RBC lysis
What clinical signs are indicative of Redwater disease?
- reddish discoloration of urine due to hemoglobinuria secondary to RBC lysis
- labored breathing
- anemia
- icterus
- dehydration, fever
What 2 lesions are indicative of Redwater disease? How is it treated?
- extremely pale animal with red urine in the bladder and thin, watery blood
- large, necrotic areas in the liver
early treatment with Penicillins or Tetracyclines and antitoxin serum
How is Redwater disease prevented?
- vaccination with 2 doses of bacterin with a booster every 6 months
- control of liver flukes
What causes black disease? What animals are most commonly infected?
Clostridium novyi Type B - infectious necrotic hepatitis
sheep > cattle on a high grain ration