Bovine Flashcards
What type of bacteria causes Anthrax
Gram-positive rod bacteria, Bacillus anthracis
Is Anthrax reportable? zoonotic?
yes and yes
What are Anthrax spores resistant to?
heat, drying, and many disinfectants
bloody discharge from orifices, absence of rigor mortis, rapid bloating, and dark blood that does not clot.
Anthrax
If you suspect anthrax, what should you absolutely not do?
Open the carcass
a. Staggering
b. Convulsions
c. High fever
d. Extensive swelling
e. Cardiac or respiratory distress
f. Depression/stupor
Clinical Signs of Anthrax
How is Anthrax Diagnosed?
submitting a blood or tissue sample
DO NOT perform a necropsy
What is the most common presentation for humans infected with Anthrax.
Cutaneous Anthrax (95% of cases)
What do clostridial bacteria produce?
Endospores
Epidemiology of Blackleg
mainly cattle between 6 months and 2 years of age. In sheep, it is almost always due to a wound or at parturition.
Clinical Signs of Blackleg
● Lameness, fever, depression, anorexia
● Swelling with possible palpable crepitus from gas bubbles
● Animals die rapidly without signs of illness (within 12-48 hours)
Diagnosis of Blackleg
● Presumptive diagnosis can be based on gaseous swelling in a young animal.
● On postmortem, the infected area is black and necrotic with gas bubbles.
a. A foul, sweet odor, often described as resembling “rancid butter”, is present
Treatment of Blackleg
The disease is often fatal unless identified early and treated with penicillin.
a. Survivors may have permanent deformity.
Carcass should be immediately disposed of without contaminating environment.
Prevention of Blackleg
Prevented by vaccination with 7-way bacterin vaccine: two doses at one-month intervals.
a. Often given as a “7-way” vaccine against Clostridium chauvoei, septicum, novyi types A and B, sordellii and perfringens types C & D.
What causes Blackleg?
Clostridium chauvoei
What causes Redwater Disease?
(Clostridium haemolyticum)- Bacillary Hemoglobinuria
How does Clostridium haemolyticum cause infection
● Endospores are ingested and the bacteria lodge in the liver.
● When damage occurs in the liver (often due to the liver fluke, Fasciola hepatica),
the bacteria replicates.
● The toxin released results in red blood cell lysis.
Clostridium haemolyticum (Redwater) clinical signs
●Reddish discoloration of urine due to hemoglobinuria secondary to red blood cell lysis
● Labored breathing
● Anemia, icterus
● Dehydration, fever
Clostridium haemolyticum (Redwater) Diagnosis
● Extremely pale animal with red urine in the bladder and thin, watery blood.
● Often a large necrotic area in the liver.
Clostridium haemolyticum (Redwater) Treatment and Prevention
● Early treatment with antibiotics (penicillin or tetracycline) and antitoxin serum.
● Prevented by vaccination with two doses of bacterin with booster given every 6 months,
and by controlling liver flukes.
What causes Black Disease
(Clostridium novyi Type B) - Infectious Necrotic Hepatitis
How does Clostridium novyi Type B cause disease
● Endospores are ingested, and the bacteria lodge in the liver (similar to C. haemolyticum).
a. In sheep, the liver fluke, Fasciola hepatica, plays an important role in the disease in creating a desirable environment for the bacteria to grow.
● Toxins released cause severe liver damage and result in red blood cell destruction.
What species does Black Disease Clostridium novyi Type B primarily effect?
Sheep
Black Disease, Clostridium novyi Type B clinical signs
Sheep are often found dead, with no evidence of clinical signs
Diagnosis of Clostridium novyi Type B (Black Disease)
Large areas of damaged tissue in liver appear gray to black with a foul smell.
Prevention of Clostridium novyi Type B (Black Disease)
Prevented by two doses of 7-way bacterin vaccine.
What causes Tetanus?
Clostridium tetani
Transmission and Epidemiology
of Tetanus
● Found worldwide and can affect most animals, although horses and pigs are most susceptible.
● Organism is found widespread in soil and is introduced through injuries such as puncture wounds, castration sites, banding, and dehorning.
a. Organism does not actively invade or create a larger wound.
● Incubation period of 10-21 days followed by production of a potent nervous system toxin
What species are most susceptible to tetanus
horses and pigs
Clinical Signs of Tetanus
● Extended “sawhorse” stance
● Difficulty chewing food (“lock jaw”)
● Stiff tail, prolapsed third eyelid, flared nostrils
● Severe muscle tremors/spasms
● Sensitivity to noise and movement
Treatment of Tetanus
tranquilization and antibiotics (penicillin), tetanus antitoxin, and supportive care to prevent dehydration or starvation.
Prevention of Tetanus
vaccination and by diligent cleaning of surgical instruments, placing animals in clean
environment after surgical procedures.
What causes Botulism
Clostridium botulinum
How do animals get botulism
Usually introduced through contaminated feed (dead cat or rabbit in silage or hay)
Shaker foal syndrome is another name for…
Botulism
Botulism Clinical Signs
Starts with muscle tremors and fasciculations, then ascending paralysis leading to respiratory
paralysis and death. Mydriasis and ptosis, as well as a weak tongue often seen.
Diagnosis of Botulism
Detection of toxin in serum, intestine, or feed for confirming the diagnosis and type.
Prevention of Botulism
Type B vaccine available; requires 3 doses at 4-week intervals. Booster dose to mare 8 weeks before foaling. Colostrum will protect foal for 8 to 12 weeks.
Transmission and Epidemiology of Enterotoxemia (Clostridium perfringens Type B, C and E)
Usually seen in **calves, lambs, kids, piglets, or foals less than 7 days old. **
A normal GI tract inhabitant that only causes disease under certain circumstances.
At what age is Enterotoxemia (Clostridium perfringens Type B, C and E) most frequently seen
calves, lambs, kids, piglets, or foals less than 7 days old
Diagnosis of Enterotoxemia (Clostridium perfringens Type B, C and E)
Extremely reddened sections of fluid-filled small intestines; “purple gut”.
Treatment and Prevention of Enterotoxemia (Clostridium perfringens Type B, C and E)
● Usually fatal once signs are present. Can attempt to treat by correcting dehydration and electrolyte imbalances with IV fluids and giving broad spectrum antibiotics and specific antitoxin.
● Prevention by herd vaccination. Can administer antitoxin (antiserum) at birth or can vaccinate dam twice with bacterin/toxoid.
What causes Overeating Disease in cattle, Pulpy kidney in sheep
Clostridium perfringens Type D
Why is Clostridium perfringens Type D called Overeating disease
Because it is a normal GI tract inhabitant that only causes disease after excessive ingestion of feed or grain.
Prevention of Clostridium perfringens Type D
two doses of 7-way bacterin vaccine
What does Clostridium perfringens Type A cause?
jejunal hemorrhage syndrome (JHS also called hemorrhagic bowel syndrome, or
hemorrhagic enteritis in adult dairy cattle), as well as yellow lamb disease, intestinal clostridiosis in horses and others.
Clinical Signs of Clostridium perfringens Type A
● Cows affected with JHS may be found dead acutely or have normal to subnormal temperature, increased HR, enlarged abdomen (ileus), and may have digested or clotted blood in feces if they live long enough.
● Lambs show icterus, weakness, and death occurs rapidly.
jejunal hemorrhage syndrome diagnosis
abdominal US and finding increased small intestinal
diameter. Hyperglycemia, hyponatremia, hypochloremia, hypokalemia, and hypermagnesemia frequently occur.
yellow lamb disease clinical signs
hemolysis, anemia, hemoglobinuria, icterus, fever. Death occurs rapidly.
Clostridium perfringens Type A prevention
NO vaccine in the US
increasing the amount of long
stem fiber in the diet has decreased the number of cases of JHS in cattle.
