Mastitis

Question 1

Define mastitis

Answer 1

non-specific inflammation of 1 or more quarters of the mammary gland

Question 2

What is the primary cause of mastitis?

Answer 2

bacterial invasion & replication within mammary tissues

Question 3

List the 4 defense mechanisms of the mammary glands

Answer 3

• teat sphincter muscle
• keratin lining of teat canal
• mucosal folds of teat canal
• phagocytic cells that populate the teat epithelium & can also enter milk

Question 4

How does subclinical mastitis present?

Answer 4

presence of pathogenic bacteria within the mammary gland and milk and the absence of mammary gland or milk changes

Question 5

How does clinical mastitis present?

Answer 5

ranges from clot or flake formation in the milk w/ abnormal color and normal to mildly swollen affected quarter(s) OR firm, swollen, hot quarter(s) with significant changes in character of the milk including obvious clots and hemorrhage; endotoxemia and death possible

Question 6

Define somatic cell count

Answer 6

indicator of number of epithelial and inflammatory cells within the milk (of the herd)

Question 7

Define California Mastitis Test (CMT)

Answer 7

a dish for each teat with reagent added to milk and evaluated for reaction

Question 8

What is a contagious pathogen? How is it transferred?

Answer 8

• Dz causing microorganisms transferred from animal to anima or via fomite l that don’t survive well or live long in enviro.
• Transferred via hands, paper towels, teat dip containers, milking equipment

Question 9

Examples of Dz causing pathogens

Answer 9

Strep. agalactiae
Staph. aureus
Other Staph species
Corynebacterium bovis

Question 10

What is an environmental pathogen? How is it spread?

Answer 10

• Dz causing microorganisms that survive and thrive within the environment but also have the ability to proliferate within animal tissue
• Live in bedding, milking machines, teat dip containers

Question 11

Examples of environmental pathogens

Answer 11

Strep. species (other than Strep. agalactiae)
Pseudomonas
E. coli
Klebsiella
Enterobacter

Question 12

How does one collect sterile milk for culture and sensitivity testing?

Answer 12

• Teat cleaned w/ disinfectant
• Teat end scrubbed w/ alcohol
• Sample collection tube sterile
• Hold tube near end of teat, almost horizontal
• Remove and hold cap sterilely
• Hand milk stream of milk into tube
• Replace cap
• Apply teat dip
• Refrigerate until submission

Question 13

Which two bacteria can be economical to treat if infection caught early in lactation cycle?

Answer 13

Strep. agalactia and Strep. uberis

Question 14

What is a big consideration for the farmer over whether to treat?

Answer 14

• Milk producing cows on antibiotics must have milk discarded = loss of $$$
• Antibiotic therapy usually initiated in dry cow formula when lactation has stopped

Question 15

How long does the teat tip remain open after milking?

Answer 15

several hours

Question 16

Management practices to consider to decrease the chances of getting mastitis

Answer 16

• Clean teat on entrance to milking parlor with disinfectant teat dip
• Dry each teat with its own individual, single-use paper towel
• Do not spray udder w/ water b/c it will drip down to the teat tip and cause contam.
• Machine applying suction beyond time that milk if slowing appropriately can increase pressure on teat and cause teat trauma
• Linings of teat cups should fit well and not slip; if slip, can damage teat or allow for air to be blown up the open teat canal
• Do a post-milking teat dip and let teats air dry
• Make sure to clean teat dip containers and milking equipment
• Provide adequate water source and food source immediately following milking
• Minimize amount of time cow has to stand before milking
• Avoid straw and wood chip bedding b/c it allows certain bacteria to grow
• Adequate housing to avoid overcrowding that can cause cows to stand for longer and results in a continually contaminate environment w/ urine and feces
• Stalls should be designed to minimize contact with feces and urine
• House should be cleaned routinely