Herd/Flock Infection, Health, and Immunity

Question 1

infectious disease

Answer 1

pathogen causing infection and disease

Question 2

contagious disease

Answer 2

requires transmission from one animal to another

Question 3

shedding

Answer 3

pathogen is released from the host, through tears, urine, feces, skin, and aerosols

Question 4

blackleg

Answer 4

infectious, NOT contagious disease in cattle, caused by Clostridium chauvoei, rapid mortality, bacterial spores are present in soil

Question 5

bovine viral diarrhea

Answer 5

infectious and contagious disease of cattle, spread by direct contact through respiratory and breeding, spread by indirect contact through contaminated species, virus enveloped and not stable in the environment, some animals carry the virus

Question 6

blackleg control measures

Answer 6

good pasture management through avoidance, preventing overgrazing, and keeping unvaccinated animals off the pasture, and biosecurity through vaccination programs

Question 7

bovine viral diarrhea control measures

Answer 7

cleanliness of stalls, isolate sick animals and identify carriers, biosecurity through vaccination program

Question 8

herd immunity

Answer 8

developed by retaining immune cows, raising the calves, and avoiding the introduction of foreign, non-immune cattle

Question 9

concept of herd immunity

Answer 9

herd immunity is important for ubiquitous pathogens and it is pathogen specific

Question 10

percentage of immune animals for herd immunity

Answer 10

high percentage of non-immune animals in a group allows the spread of infection when the pathogen is introduced

Question 11

how are chains of infection disrupted?

Answer 11

when most animals have a high level of immunity

Question 12

how is herd immunity achieved?

Answer 12

when sufficient animals are immune such that introduction of disease does not result in an outbreak