ANSC PATH FINAL - sudden death in livestock

Difference in disease incidence and severity of depends on

Host factors, environmental factors, agent factors, and nutritional factors

Consider temporal patterns

When did the first case occur? Is there a seasonal pattern? How rapidly did the disease spread through herd?

Consider individual animal data

What ages are affected? What sexes? What breeds? Native to farm? Obtained from somewhere else? Vaccination history? Anti parasitic treatment history?

Confirmation of outbreak has to do with the

Attack rate

Attack rate is the

Number of new cases/ total animals at risk

Expectations for necropsy

May not find “smoking gun” - may look normal, a little off, or severe

Consider sending necropsy samples to diagnostic lab such as

Tissues, blood, CSF, digests, aqueous humor, urine

Clostridial disease is a bacterial organism normally found in

Soil, water and GI tract of animal, gram positive, anaerobic, spore forming

Clostridial spores are

Highly resistant and persist for years in enviroment

Clostridial disease are

Exotoxin producers

Three types of clostridium organisms most common is

Clostridium chauvoei - “black leg”

Clostridial myositis is known as

“Gas gangrene” of skeletal muscle that may include cardiac muscle and uterus

Clostridial myositis is most common in

Young cattle

Clostridal myositis is triggered by muscle damage from

Long hauls, chute work, cattle periods

Clinical signs of clostridial myositis are

Sudden death (systemic toxemia), lameness, fever, and subcutaneous emphysema (thigh, round, shoulder, neck, brisket)

Clostridial hepatitis is most common in

Adults

Costal hepatitis toxin production causes

Blood hemolysis and death

Clinical signs of clostridial hepatitis include

Sudden death, hemolysis (port-wine colored urine (from hemoglobinuria))

Clostridal enteritis include

C. Perfringens type A, B, C, and D and death can and does usually precede any signs of enteritis

any severe gram-negative bacterial infection can lead to acute death due to

Endotoxemia

Clinical signs of pasteurellosis include

Excessive salivation, foamy mouth, not necessarily “snotty nose”

Anaplasmosis is a parasitic (protozoan) organism of the

Red blood cells (anaplasma marginale) and are more common in southern states

Clinical signs of Anaplasmosis include

sudden death, pale, icteruc mucous membranes, depression, respiratory distress, off fees, behavior bizarre, aggressive (due to hypoxia)

Anaplasmosis can be diagnosed with

Serology

Anaplasmosis can be treated with antibiotic

Tetracycline

Prevention of Anaplasmosis

Minimize tick exposure, do not reuse needles in multiple cattle

Animals that recover from Anaplasmosis are

Chronic carriers

Lighting strike/ electrocution leads to death from

Asphyxiation from paralysis of respiratory muscles