Mastitis

Question 1

What is mastitis?

Answer 1

Inflammation of the mammary gland, usually due to bacterial infection.

Question 2

CSs mastitis

Answer 2

clotting + discolouration of milk
swelling & discolouration of udder ± fever
anorexia
can lead to death!
Pain

Question 3

Issues with mastitis

Answer 3

Financial impact - milk losses, increased risk of culling, reduced fertility.
Public health - abx use + zoonosis

Question 4

Teat canal barriers

Answer 4

Kertain plug - between milking & during dry period.

Spincter - closes 2hrs post milking.

Question 5

Pathology caused by mastitis

Answer 5

1. toxins can damage mammary tissue - reduced production
2. clots may form blocking ducts
3. scar tissue leading to loss of function

Question 6

Examples of infectious teat lesions

Answer 6

1. Teat end hyperkeratosis
2. cowpox
3. pseudocowpox
4. bovine papillomatosis
5. BHV-2
6. Fusobacterium necrosporum - black spot
7. impetigo - staphylococcus spp.
8. ringworm
   (FMD, vesicular stomatitis)

Question 7

When do most mastitis infections occur?

Answer 7

During 1st 3 weeks of dry period + 1st month PP

Question 8

What are coliform?

Answer 8

Normal inhabitants of soil, digestive tract and slurry

Question 9

Examples of coliform

Answer 9

E. coli
Klebsiella pneumoniae
Enterobacter aerogens

Question 10

Grading of mastitis

Answer 10

1 - changes to secretion only
2 - secretion + udder
3 - +systemically unwell

Question 11

Definitive dx of mastitis requires

Answer 11

Bacteriology sample of aseptically collected milk

Question 12

What does SCC measure?

Answer 12

Leukocytes + epithelial cells

Question 13

SCC individual cow

Answer 13

<100,000 healthy

>200,000 infection present

Question 14

SCC bulk milk

Answer 14

<100,000 cells/ml excellent mastitis control
100,000-200,000 low level SC mastitis
200,000-300, 000 mastitis present
>300,000 = contagious mastitis problem
>400,000 not considered safe for human consumption

Question 15

California mastitis test

Answer 15

Accurate prediction of SCC using reagent with pH indicator

Increased stringing & colour change if increased SCC

Question 16

Heard monitoring of mastitis

Answer 16

SCC & bactoscan

Question 17

Intramammary antibiotics

Answer 17

Best for generally non-invasive organisms - strep algalactiae, coagulase -ve strep.
Fibrin and microabsesses interfere with distribution

Question 18

Sub-clinical mastitis

Answer 18

Causes an increase in inflammatory cell mediators but no obvious changes to milk. Increased SCC