bovine causes & transmission

Question 1

• Complex of viral and bacterial infection and stress.
• Young cattle most likely affected:
- Beef calves during the first 45 days at the feedlot.
- Dairy calves less than 6 months of age.
• The viral infection comes first, then a secondary bacterial infection.

Answer 1

Bovine Respiratory Disease Syndrome (BRDS)

Question 2

• Uterine infection
• Abortion
• Birth defects

Answer 2

Bovine Viral Diarrhea- BVD

Question 3

Spread by the bull to cows and heifers.

Answer 3

Leptospirosis and Vibriosis

Question 4

Excessive quantities of highly fermentable carbohydrates, such as grain, cause the bacteria in the rumen (which breaks down lower quality feed) to make lactic acid.
• The excess lactic acid decreases the pH of the rumen
• The low pH degrades the lining of the rumen.
• Lactic acid leaks out into the blood stream causing metabolic acidosis.

Answer 4

Rumen Acidosis

Question 5

• Perforation of the reticulum and rumen by an ingested foreign object.
• The object causes an abscess in the abdomen or pericardium.
• Vagal indigestion: the Vagus nerve controls the movements of the digestive tract and heart rate. If the nerve is inflamed, the movement of the digestive tract slows down as well as the heart rate (>65 bpm)

Answer 5

Hardware Disease or Traumatic Reticuloperitonitus (TRP)

Question 6

Calves > 6 mo. infected by oral-fecal route.

Answer 6

Johne’s Disease

Question 7

Colostrum containing Mycoplasma bovis may be a source of infection.

Answer 7

Mycoplasma pneumonia

Question 8

infection with anaerobic bacteria in the Clostridium family
• Spores from the bacteria enter the tissues through:
- GI tract
- Injuries

Answer 8

Black Leg and Malignant Edema

Question 9

• Most new infections occur in early lactation.
• High producing cows are at higher risk – more stressed
• Poor management of housing and bedding.
• Poor maintenance of milking equipment.
• Poor milking hygiene.
• Teat ends or streak canal is damaged, allowing bacteria to gain entry.
• Or, improperly functioning milking equipment force milk up the streak canal.
• Or, the cow lays down in manure and mud right after milking, when the streak canal is open.

Answer 9

Mastitis

Question 10

3 GI parasites:
	- Haemonchus 
	- Ostertagia
	- Trichostrongyle
• Most common in young animals 4 to 12 weeks of age.
• Can occur at any age.

Answer 10

H.O.T. Complex

Question 11

• Oocyst (like eggs) are in the soil and feces and can survive for years.
• Oocysts must sporulate to become infective.
• Oral route of infection of sporulated oocysts.

Answer 11

Coccidiosis

Question 12

a deficiency in the B vitamin, Thiamine (B1)

Answer 12

Polioencephalomylacia in Sheep and Goats (Polio)

Question 13

• Overweight ewe or doe: Fat takes up space in the abdomen, limiting feed intake.
• Multiple fetuses: huge nutritional drain on doe/ewe & lack of space for rumen.
• Overfed doe/ewe during the last 2 months of gestation (same as over wt).
• Undernutrition: Starvation or parasitism.
• Feeding alfalfa – link to hypocalcemia.

Answer 13

Pregnancy Toxemia or Ketosis

Question 14

a combination of bacteria from the environment.

Occurs shortly after farrowing.

Answer 14

MMA (Mastitis Metritis Agalactia)

Question 15

Young pigs most affected, but can occur in all ages of pigs

Answer 15

TGE (Transmissible Gastroenteritis)

Question 16

Combination of bacterial and viral upper respiratory infection.

Answer 16

Atrophic Rhinitis