Promoting Animal Health from a Herd Standpoint

Question 1

What are the objectives of production medicine?

Answer 1

• promote animal health and maintain production at the most efficient level to ensure maximal economic return to herdsmen
  
  • animal comfort/welfare
  • environmental impact of agriculture
  • control of zoonoses
  • product contamination and residue avoidance
    *

Question 2

What are some trends seen in the dairy industry in the US?

Answer 2

• incr in milk produces and number of cows
• decr in operations w/ milk cows, but incr in cows/farm
• cows now have incr levels of β-hydroxybutyrate (BHBA)

Question 3

What are the 3 parts of the herd health managemeny feedback cycle?

Answer 3

1. monitor and assess current status
   
   • goals, targets, and/or industry standards
2. make decisions, develop plans, and take action
   
   • effects of external factors
3. performance outcome

Question 4

What is the clinical definition of disease?

Answer 4

a condition of the living animal or plant body or of one of its parts that impairs normal functioning and is typically manifested by distinguishing signs and symptoms

Question 5

Subclinical diseases are often:

Answer 5

• more difficult to diagnose
• more prevalent within herds
• more costly to production systems
• less obvious and harder to convince herdsmen to take action

Question 6

What are some examples of poor performance or productivity of a herd that are the result of subclinical disease?

Answer 6

• decr twinning in sheep
• decr peak milk production
• decr preg rate
• decr # of calves/piglets weaned

Question 7

What is the classical definition of cause?

Answer 7

• “factor” is present in all animals with the dz
• “factor” is not present in any animal w/o the dz
• healthy animals treated w/ the isolated “factor” develop the dz
  
  • however, this definition is too restrictive for most syndromes in production medicine

Question 8

What is a sufficient cause?

Answer 8

• collection of conditions and events

Question 9

What are some common pitfalls in monitoring parameters?

Answer 9

• lag - interval b/t the problem and the ability to detect it; delays change
• momentum - effect of time; recent vs. old/resolved vs. old/unresolved issues
• variation - false changes in averages; praise to irrelevant changes or unwarranted alarm d/t a single individual’s problem
• bias - incorrect info

Question 10

What is the difference between a type 1 and type 2 error?

Answer 10

• 1: false positive
• 2: false negative

Question 11

For screening, it is better to have _____ rather than _____ tests

Answer 11

sensitive; specific

Question 12

What are the main goals of monitoring parameters and stastical inference?

Answer 12

detect pattern changes, monitor performance, and assess implemetation of new strategies/technologies