LA Mastitis

Question 1

What are the 2 anatomical defense mechanisms of the udder?

Answer 1

1. suspensory ligaments: lateral lig support the weight of the udder (higher udder = less contact with ground) and median lig. provides weight suport and teat alignment
2. teat canal with sphincter (stays open 2 hr post milking) and keratin lining of teat canal (bacteriostatic, sticky to trap bacteria)

Question 2

What are the 4 somatic cells that act as a defense mechanism for the udder?

Answer 2

1. T lymphocytes
2. macrophages
3. neutrophils
4. alveolar cells

Question 3

What secretory antibody acts as a defense mechanism for the udder?

Answer 3

IgG

Question 4

________ is the whey protein that increases during udder involution and binds iron which is good because some bacteria need iron.

Answer 4

lactoferrin

Question 5

Cows with lower levels of _______________ and lactoperoxidase are MORE susceptible to mastitis

Answer 5

lysozymes

Question 6

what are the 2 time periods that animals are MOST at risk for mastitis?

Answer 6

2 weeks PRIOR to giving birth
2 weeks AFTER giving birth

Question 7

what is the role of oxytocin as a mammary gland defense?

Answer 7

causes milk let down which flushes the udder and drains any potential pathogens out

Question 8

what blocks oxytocin?

Answer 8

epinephrine

Question 9

List the steps to milking a cow:

Answer 9

1. put on gloves
2. wet the udder, then manually clean the teats (this stimulates oxytocin release in addition to sights/sounds)
3. use pre-dip to reduce environmental mastitis and leave on teats for 30 sec minimum, then remove with clean towel
4. strip the teat foremilk to remove bacteria and somatic cells – examine the foremilk for garget or flakes
5. kink teat cups and then place teat cups onto teats
6. after 5-6 min, remove teat cups once milk flow has reduced/stopped
7. use post-dip
8. remove residual milk from teat cup by back flushing in order to prevent bacteria from one cow being passed to another
9. remove cows from parlor and immediately provide feed/water to prevent them from lying down and exposing open teat canals to environmental orgs

Question 10

__________ is inflammmation of the udder

Answer 10

mastitis

Question 11

What causes mastitis in small ruminants?

Answer 11

retroviruses – OPP and CAE

Question 12

T/F: mastitis can be caused by physical trauma (overmilking, vacuum problems, and general trauma)

Answer 12

true

Question 13

How should you collect a milk sample?

Answer 13

1. wipe off teats with towel
2. squirt out some milk
3. wipe bottom of each teat with alcohol 4x4 until clean (far teats first, then near)
4. sample teats (near teats first, then far)
5. hold tube horizontally and squirt milk into tube
6. put labeled tubes on ice and wash hands

Question 14

_____________ is an obligate parasite of the udder that is highly contagious. It does not actually invade the tissue, but it lines the duct epithelium and produces local toxins. It causes acute and chronic subclinical mastitis with high SCC counts.

Answer 14

streptococcus agalactia

Question 15

Which organism is considered the only mastitic organism that can be eliminated from the herd and responds really well to antibiotics (procaine penicillin Intramam.)?

Answer 15

streptococcus agalactia

Question 16

How can you prevent a streptococcus agalactia infection?

Answer 16

its in transmitted from infected udders to clean udders during milking (hands, cloths, or residual milk)
1. have good milking hygiene (wash hands, use individual paper towels, use back flush system)
2. dry cow treatment

Question 17

Streptococcus dyslactia is NOT an obligate organism, but is found in the mouth, vagina, and lungs. These infections are not as responsive to antibiotics as S. agalactia are. What risk factors are these infections associated with?

Answer 17

teat end damage or injury

Question 18

how do you prevent S. dysgalactia infections?

Answer 18

milk clean and dry udders
reduce teat end damage

Question 19

What organism is considered the “fecal strep” associated with dirty environments and bedding?

Answer 19

Strep uberis

Question 20

_________ is a contagious bacteria that colonizes the teat and udder skin following an injury (sunburn, freezing, chapping). It is spread between cows during milking (hands or improper procedures).

Answer 20

staph aureus

Question 21

A cow presents to you with a fever of 104 and a swollen cold edematous udder with a strong line of demarcation. You do TPR and the HR is 110. You milk the cow for a sample and the milk is wine colored with no clots. What is most likely the diagnosis?

Answer 21

gangrenous mastitis

Question 22

A cow presents to you with a fever of 105 and a swollen, hard, painful udder. You do TPR and the HR is 110 and this cow is dehydrated and recumbent. You take a milk sample and its watery with garget. The agent you cultured is E. coli. What is most likely the diagnosis?

Answer 22

peracute systemic mastitis

Question 23

Why are organisms involved in staphyloccocus aureus chronic or subclinical mastitis resistant to antibiotic treatment?

Answer 23

the organism invades the walls of the tissues and causes granulomas. The antibiotics cannot penetrate the abscess wall.

Question 24

What is the treatment for gangrenous mastitis caused by staph aureus?

Answer 24

amputate the teat to get drainage
IV fluids
systemic antibiotics

Question 25

what is the treatment for peracute and acute staph aureus mastitis?

Answer 25

1. fluids -- hypertonic (oral or IV) 2. antibiotics: tetracycline IV 3. analgesics -- banamine 4. Ca borogluconate/CMPK 5. oxytocin and milk out

Question 26

how do you prevent staph aureus mastitis?

Answer 26

1. cull infected individuals to reduce exposure to naive cattle 2. milk staph cows LAST 3. teat dip ALL cows to reduce colonization 4. proper sanitization during milking 5. backflush system

Question 27

__________________ are common inhabitants of bovine and human skin. They are considered opportunists that colonize teat end leasions, teat trauma, viral lesions, etc. They cause acute mastitis with small white flakes and inflamed udder.

Answer 27

coagulase negative staphs (s. epidermidis, s. simulans, s. warneri, s. xylosis)

Question 28

What is the treatment for mastitis caused by coag negative staphs?

Answer 28

commercial mastitis infusions (sythetic penicillin) 3x intramammary. to prevent, teat dip and be clean. dont forget to do dry cow treatment.

Question 29

______________ is an organism that causes "summer mastitis" because it is transmitted by flies and associated with teat injury/laceration. These infections often become chronic and form abscesses.

Answer 29

trueperella pyogenes

Question 30

_________ are environmental contaminants that are transmitted during the milking process or in the environment. They cause acute mastitis with watery milk secretions containing yellow material (like egg drop soup). The udder of these cows will be enlarged and painful. She will have increased temp, be depressed, and anorexic.

Answer 30

coliforms

Question 31

A cow presents to you with normal teats and normal udder. The cow herself seems normal as well. The milk secretions appear normal, but the SCC is high. What is the diagnosis? *bonus if you can say what organisms are most likely the cause*

Answer 31

subclinical mastitis contagious orgs streptococcus coag neg staphs rarely coliforms

Question 32

what is the treatment for mastitis caused by coliforms?

Answer 32

1. milk out affected quarter 2. anti-inflammatories +/- steroids 3. IV antibiotics (tetra) 4. fluids (oral or IV) + calcium

Question 33

how do you prevent mastitis infections that are caused by coliforms?

Answer 33

clean the environment only milk dry udders post dip to provide barrier feed cows after milking to prevent laying down.

Question 34

why do we do dry cow treatment?

Answer 34

1. udder involution -- allows tissue to heal and clear infections 2. give the cow a rest 3. prepare for next lactation -- udder tissue develops and colostrum is produced

Question 35

describe dry cow treatment

Answer 35

1. discontinue milking -- decrease feed, NO grain, remove water if needed 2. infuse dry cow treatment (oil-based antibiotic) 3. dip teats with teat dip for barrier 4. place in clean environment

Question 36

A goat presents to you with a fever and is off feed. The teats are hard and and swollen and the milk is mostly normal other than a little bit of silt settling at the bottom of the sample tube. What is the most likely cause of this mastitis?

Answer 36

mycoplasma bovis

Question 37

How do you perform a california mastitis test?

Answer 37

squirt equal parts of milk to reagnent into the paddle swirl milk and reagent look for coagulation negative = no film trace = some film but disappears in 15 sec -> subclin mastitis 1 = see film and doesnt disappear --> possibly infected 2 = thick film, slight gel --> most likely infected 3 = very thick precipitation, pours like jelly --> infected