Mastitis

Question 1

Wholesome product

Answer 1

No adulteration/contamination

Drug residue issues

Question 2

Welfare

Answer 2

Freedom from pain, injury, disease

Question 3

Processor perspective

Answer 3

Number of bacteria impacts shelf life
Abx interfere with cultures
Mastitis changes milk composition and increases pH

Question 4

Producers perspective - cost of mastitis

Answer 4

Lost milk production
Direct tx costs
Indirect cost of premature culling
Loss of quality bonuses

Question 5

On farm

Answer 5

Cooled to 10c within 4hrs or less. 7c within 2hrs after completion of milking.

Question 6

Traditional pasteurization

Answer 6

(72C) 161F for 15sec before rapid cooling
Destroy M. Tuberculosis, coxiella burnetti, brucella abortus
Refrigerated life of 2-3wks

Question 7

Ultra pasteurization

Answer 7

> 280F for at least 2sec

Allows for extended shelf life under refrigerated (4-8wks)

Question 8

Aseptic processing

Answer 8

Hold milk at 280F for at least 2sec

Can be stored unopened and unrefrigerated for long periods of time

Question 9

Peracute mastitis

Answer 9

Sudden, severe

May include shock, septicemia, loss muscle coordination, cold extremities

Question 10

Subclinical mastitis

Answer 10

Not detected visually 
Elevated SCC
causes great economic loss
Clinical and subclinical can become chronic 
Lose $1billion annually

Question 11

Clinical mastitis

Answer 11

Summer in SE (heat stress, humidity)

Question 12

Causes of mastitis

Answer 12

Invasion of microorganism through teat canal
Trauma or injury to udder
Chemical irritation

Question 13

Cow defense against mastitis

Answer 13

Streak canal and muscle sphincter
Keratin plug, somatic cells
Ab and other soluble factors
Flushing action

Question 14

Somatic cells

Answer 14

Primary defense once bacT breech streak canal
3 main types: epithelial cells, macrophages, PMNs
Indicates amount of inflammation

Question 15

Factors driving SCC

Answer 15

Infection status, stage lactation, cow age, season of year, location, level of milk, time of collection

Question 16

CMT

Answer 16

California mastitis test

Rapid, subjective for subclinical mastitis

Question 17

Legal SCC limit in US

Answer 17

750,000/ml

Question 18

Contagious pathogens

Answer 18

Strep agalactiae
Staph aureus
Mycoplasma species

Question 19

Environmental pathogens

Answer 19

Strep species

Coliforms

Question 20

Contagious pathogens

Answer 20

Cow to cow spread
Udder main source, spread at milking time
Presents as subclinical usually

Question 21

Strep agalactiae

Answer 21

Gram + cocci. Only survives short periods in environment. Causes high SCC
Easiest organism to control, responds well to lactation and dry cow therapy. Post milk dipping reduces by >50%

Question 22

Staph aureus

Answer 22

Gram + cocci. Very contagious. Source of infection: infected mammary glands, colonized teat ducts, infected teat lesions
Potentially body/udder skin. Usually presents as chronic subclinical. Can have severe clinical - gangrenous, fresh 1st lact. See blind quarters. Heifers prime source of infection, control flies
Cure rate poor with abx

Question 23

Mycoplasma spp.

Answer 23

BacT with membrane, highly contagious. Economic impact. Frequently more than one quarte involved. Milk appears sandy or brownish. Often very high SCC. Can survive in semen. Shed intermittently. Once pos, always pos. direct plating on special media, limit is 100CFU. differentiate types by FA typing

Question 24

When suspect mycoplasma problem

Answer 24

No response to tx and negative cultures
Spreads from one quarter to anothe
Clinical flare ups
Don’t wait for classic grainy appearance

Question 25

Strep Uberis and dysgalactia

Answer 25

Environmental. Many new infections occur during 1st 2wks following dry off and last 2-3wks prior to calving.

Question 26

Gram neg- e. coli

Answer 26

Highest incidence in early lactation Seasonal. Most infections short duration. CS: fever, shock, milk clots, watery, bloody J5 vaccine -$60 return on investment

Question 27

Klebsiella

Answer 27

Typically more severe than e. coli | More difficult to treat, green sawdust shavings

Question 28

Management

Answer 28

``` Treatment Dry cow therapy- often most effective Mailing order- contagious last Culling Vaccination ```

Question 29

Teat canal open/dilated

Answer 29

1/2 hr after mailing | Provide feed immediately after milking

Question 30

Keratin teat plug

Answer 30

Absorbs bacT and shed at milking

Question 31

Mastitis control program

Answer 31

1. Clean environment 2. Proper nutrition 3. Proper maintenance of equipment 4. Proper pre milking prep. 5. Apply and remove machine properly 6. Post dip 7.tx and record cases 8. Routine surveillance 9. Segregation/culling 10. Dry off therapy

Question 32

Predip contact time

Answer 32

45-60sec

Question 33

Machine attached within

Answer 33

1-1.5min of priming

Question 34

Why abx fail

Answer 34

Fail to reach site of infection Resistance BacT dormancy Reinfection issues

Question 35

No need to treat

Answer 35

Mycoplasma - doesn't work

Question 36

Sources of bacT in raw milk

Answer 36

From environment Within udder In milking system

Question 37

Causes of high lpc- lab pasteurized count

Answer 37

Improper sanitation of equipment

Question 38

Cause of high coli count

Answer 38

Milking wet cows

Question 39

Pi - preliminary incubation count

Answer 39

Measure of raw milk keeping quality

Question 40

Cause of high PI count

Answer 40

Improper sanitation of milking equipment before or after milking