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Flashcards in Mastitis - Clinical presentation Deck (33):
1

What are the presentations of mastitis?

clinical or subclinical (more common)
Dry period or lactation infection
Contagious (mostly) or environmental

2

What is a dry cow infection?

One where the cow gets mastitis within the first 100 days after calving (i.e. early lactation)

3

What is Orbeseal?

An intrammammary suspension to put in the teats to prevent infection.

4

How do the bacteria generally vary between contagious and environmental causes for mastitis?

There is a scale which works generally:
CONTAGIOUS
S. agalactiae
S. aureau
S. dysgalactiae
S. uberis
E. coli
ENVIRONMENTAL

5

General causes of mastitis

Multifactorial:
Host, environmental, agent

6

Average UK incidence of mastitis

35 per 100 cows per year (40-70 quarter infections)
SE England: 45 cases/100 cows/year

7

What is an average bulk tank somatic cell count?

184,000/ml

8

What does a bulk milk tank reading of <100,000 indicate?

Fewer clinical mastitis cases but typically cases are more severe (e.g. E.coli infections)

9

Why bother with mastitis?

MILK QUANTITY (actual and potential milk)
MILK QUALITY (residues, penalty for high SCC)

10

Average cost per mastitis case?

£100 per year +/-

11

What is needed for clinical mastitis?

Pathogen exposure, entry into teat and mammary gland, establishment of infection.

12

True/false - in mastitis there are always changes in the milk

True (colour, spots, clots etc)

13

How is clinical mastitis graded?

Grades 1-3

14

Describe grade 1 mastitis

milk change only, decreased milk yield

15

Describe grade 2 mastitis

Subdivided into acute and chronic
ACUTE = milk changes, changes in the udder, milk yield decreased
CHRONIC = as acute but persistent changes (udder and milk)

16

Describe grade 3 mastitis

As grade 2 but a systemic sick cow (typically E.coli or S.aureus)

17

Pathogens involved in acute/clinical mastitis - 6

(S. agalactiae) - subclinical
S. dysglacactiae (teat injury)
S. uberis (envi)
S. aureus (contagious)
E. coli
Exotic agents: Klebsiella, Salmonella, yeasts, Bacillus cereus, Mycoplasma.

18

Will you have a positive California Milk Test (CMT) with subclinical mastitis?

Yes

19

How would you perform a CMT (OSCE!!!)?

wipe teat,
wear gloves (show best practice)
strip pre-milk (highest SCC)
take sample
remember paddle orientation
add reagnet to disrupt membrane and cause DNA to branch out
Assess - there is some grading as to the outcome (slight/very positive result)

20

Pathogens implicated in chornic/sub-clinical mastitis

S.aureus
S.uberis
S.agalactiae
Corynebacterium bovis

21

What are the important aspects of mastitis history?

duration, development, stage of lactation and gestation, age, treatment and its response, previous episodes, SCC data from NMR, other cases in herd?? records?

22

What are the important aspects of mastitis clinical exam?

systemic clinical exam
udder exam (inspect, palpate, LNs)
milk exam
Milk sample - CMT

Preliminary Dx and Tx

23

Is Baytri a systemic treatment?

Yes

24

What features do ABs need to have for mastitis treatment? 3

systemic,
intramammmary during lactation
intrammammary in a dry cow
ABOVE TWO ARE DIFFERENT, DO NOT CONFUSE!!!

25

What does AB choice depend on?

sensitivity, pharmacokinetics, availability, costs, herd history, withdrawal time

26

Other treatment options for mastitis - 5

Oxytocin - helps milk letdown which is important to encourage in mastitis cases
NSAIDs
Corticosteroids - controversial
fluid therapy -esp toxic mastitis
calcium
dextrose

27

Why do a culture?

You can never tell on basis of clinical presentation (remember you can use a PCR to determine specific pathogen)
AB sensitivity
Select your samples (recurrent, persistent, risein SCC)

28

When should you freeze sample?

Always (in case of treatment failure)

29

What are the different milk samples that can be taken? 3

Bulk tank sample
Pooled sample of one cow
Individual quarter sample

30

How should you take a sample?

Cleanse udder
Swab teat end
2 pre-strips
2ml in sterile container
Label name, cow number and quarter
USE GLOVES!!

31

For what reasons does prevention vary?

Per bug and per farmer. Starts with records.

32

How many samples on average return sterile?

40%

33

How should you assess your performance?

on % of contamination (aim for <10%)