Animal Sciences - Infectious diseased of domestic animals

There are also examples of clostridium and parvovirus notes

Infection

disturbances resulting from entrance , growths and activity of disease-causing organisms in/on an animals body. Does not mean contagious

Contagious

Spread from one animal to another by direct or indirect contact

Disease transmission implies?

• presence of a pathogenic organism in sufficient numbers

• Direct or indirect contact

• Portal of entry

Fomite

Takes part in indirect contact transmission (water, food, air, things)

Vectors

Takes part in mechanical transmission or biological transmission (animals, insects, humans)

How host gets infected

Microorganism sources → direct or indirect transmission → host animal

Exposure

Does NOT mean infection occurs, this depends on many factors and we can reduce the risk of infection by addressing the factors

3 factors of exposure

• dose

• Pathogenicity of disease agent

• Immune status

Dose

Number of bacteria (or virus partials, etc.) that challenge the animal

Pathogenicity

Organisms ability to reach the animal invade, infect, and multiply enough to cause disease, relates to invasiveness, production of harmful substance, and damage to cells/tissue

Invasiveness

The organisms ability to spread from the initial invasion site of to gain entry to the circulatory system

Production of harmful substances

Pathogenicity of an organisms ins often due to toxins or enzymes it produces that interfere with the function or metabolism of the animal

Damage to cells/tissue

Attack on immune cells or other body defences may further weaken the body’s ability to respond or fight the disease

Immune Status

The animals ability to fight of the disease organism (primary and secondary defences)

What are some factors to consider that affect immune status

• age (young or old)

• Previous exposure and specific acquired immunity

• Vaccination

• Other health conditions or stress

• Nutrition

How can we reduce the risk of infection

• dose: clean environment, masks

• Pathogenicity: we can’t doo much about the infectious agent

• Immune status: keeping patient at peak health and reduce stress