Mastitis control

Question 1

Discuss historical treatment of mastitis?

Answer 1

Weren’t that successful in treating these cows with toxic mastitis and by time they got to that stage 50% were dead so the way forward was to work with prevention rather than cure.

Question 2

Prevention – Where to start??

Answer 2

Usually caused by Gram – (e,g e.coli)

Week or so after calving cows would become severely ill. In terms of immune function this period is where they are most vulnerable.

Before calving period dry period of few months.

Question 3

Discuss the dry period and mastitis?

Answer 3

Dry period has often been thought of as a cure state. Where SCC can go down.

However, is it possible in the dry period that these clean cows are picking up new infections.

Question 4

Mastitis research began to focus on the dry period?

Answer 4

Preliminary studies found that 40% of cows in the 6 herds study had a pathogen in quarter in dry period and non of them got mastitis in this time.

Question 5

Did these dry period infections found in the research cause mastitis?

Does the same organism in the dry period go on to cause mastitis in the milking period?

Answer 5

In nearly all incidences the isolate found in the dry period was the isolate which caused the mastitis after calving

Question 6

Look at these gel electrophoresis of dry period pathogens DNA and mastitis DNA pathogens in the same cows and explain it?

Answer 6

White boxes represent individual cows. Between cows strains were different but each individual has bacteria traced from DP through to lactation.

Therefore conclusions need to look at DP management.

Question 7

What did the initial dry period research find?

Answer 7

• First study to follow bacteria from dry period to mastitis after calving
• Up to 50% cows became newly infected during Dry Period
• Up to 75% of all mastitis originated in the Dry Period

Question 8

Which herds have dry period problems?

Answer 8

Graph showing from first 6 herds the survival plot.

Time to event analysis (time till mastitis occurs).

Cows with a DP infection can see cases of mastitis happen very soon after calving/first 30 days.

Question 9

Discuss Origin of Clinical mastitis
Lactation Distribution?

Answer 9

Most cases in the 1st month come from dry period infections. Over time ratio of red to yellow reduces

Question 10

How can we stop it?
…prevention?

Answer 10

Question 11

Dry Cow Treatment:
Different Treatments work for Different Cows and Herds!

Discuss treatments tried?

Answer 11

• A Clinical Trial
• Target therapy towards a specific types of bacteria

–Gram negative

• Found a 50% reduction in clinical gram negative clinical mastitis NEXT lactation
• Confirmed that preventing DP infections does reduce mastitis after calving
• Concept of differential DCT

Question 12

What about novel, non-antibiotic treatments as opposed to antibiotics??

Answer 12

•‘Teat Seal’

–Bismuth Subnitrate in paraffin base

–Designed for use in uninfected cows

–No inherent antimicrobial activity

•Care with infusion

Infused and left in the teat cistern

• Teat sealant was better for gram – than antibiotics

And had protection as well as dry cow antibiotic therapy had

Question 13

Discuss determinants of mastitis?

Answer 13

Question 14

We can make a practical difference to dry period infections with proper
Hygiene and management.?

Answer 14

Hygiene whilst administering dry cow treatments: Surgical spirit swab before administer dry treatments

Environmental hygiene: Good drainage, Clean and bed cubicles daily, Scrape feed and loafing area daily

Yard management Dry cows need more area of space: Transition yard area > 1.25m2 per 1000L annual mean cow milk production

Dry cows at grass: Graze for 2 weeks then rest 4 weeks

Calving Period: Calves don’t have access to suckle other cows, Calving pens cleaned out daily

Other herd factors: Keep bedding materials dry

Question 15

In summary?

Answer 15

• Dry Period Infections important on many farms
• Herd with Dry Period problems can be spotted by patterns of mastitis
• Can reduce Dry Period Infections by treatment approaches and management changes

Question 16

What is AHDB Dairy Mastitis Control Plan?

Answer 16

Software allowing farms to see where they need to improve specifically

Question 17

What is the continued research for mastitis control?

Answer 17

• “Best decisions to prevent mastitis”
• None antibiotic approaches

–Immune stimulants…

•Microbiomes, vaccines

Question 18

Where are we today?

Answer 18

• Selective dry cow therapy is an industry standard driven by retailers (AMR)
• AHDB Mastitis Control Plan has been an industry initiative since 2009 – funded to at least 2021 (estimate 1/3 UK cows involved in plan)
• New research and technologies to speed up herd diagnosis to implement controls

Question 19

What are the Principles of mastitis control?

Answer 19

Prevent New Infections

Remove Existing Infections

As long as at rate of cure (and culling) exceeds the rate of new infection then progress will be made

Balance between prevention and cure and we focus more on prevention now

Question 20

In herd 1 The clinical mastitis incidence was 83 cases/100 cows/year last year. How does this compare with the UK national average?

Answer 20

Higher

Question 21

The average clinical mastitis incidence rate in the UK is likely to be between?

Answer 21

55-65 cases/100 cows/year

Awful. UK has a long way to go on mastitis control. Rate of clinical mastitis is too high in this country.

Question 22

In herd 1 The average BMSCC for the last 12 months was 90,000 cells/ml. How does this compare with the national average?

Answer 22

Lower

Question 23

The current average BMSCC in the UK is around?

Answer 23

160,000 cells/ml

Question 24

Which of these statements about Clinical Mastitis of dry period origin is true?

A.Is detected during the dry period (wrong because when cows are dry they don’t give milk so cant detect it then)

B.Results in increased CM in the first 30d of lactation

C.Is detected during lactation

D.Results in increased CM after the first 30d of lactation

E.Isn’t very important and we don’t know why you lot keep banging on about it

Answer 24

B.Results in increased CM in the first 30d of lactation

C.Is detected during lactation

Question 25

Where are the majority of new infections being acquired according to the previous graphs?

Answer 25

During the Dry Period

However mastitis is rarely black and white. Judgement made as a vet what you need to focus on whether problem in dry period or lactation and these graphs help make those judgements.

Question 26

Summarise herd 1 so far?

• 200 cow H/F Herd
• Year-round calving
• Cows housed all-year round (straw yard/cubicles)
• Far-off dry cows (the ones that have more recently been dried off) graze in the summer
• Transition cows (closer to calving) housed all year round (straw yard)
• Milked x2 daily in herringbone parlour
• Closed herd
• Vaccinates for BVD, IBR and Lepto

High than average clinical mastitis

Lower than average SCC

Answer 26

• High incidence rate of clinical mastitis
• Low bulk milk somatic cell count (indicating low prevalence of subclinical infections in this herd)
• High incidence rate of dry period origin cases
• Low incidence rate of lactation origin cases
• Elements of Seasonality

Question 27

What is your diagnosis for herd 1?

• High incidence rate of clinical mastitis
• Low bulk milk somatic cell count (indicating low prevalence of subclinical infections in this herd)
• High incidence rate of dry period origin cases
• Low incidence rate of lactation origin cases
• Elements of Seasonality

Answer 27

Environmental bugs in Dry Period

SCC indicates this is the cause as it was low. Hall mark of environmental bugs. Tend to see short lived create a spike in cell count cow quickly recovers and results in small number with active infection at that time.

Question 28

Discuss environmental dry cow period infection?

Answer 28

Question 29

Which areas are likely to be most important with respect to mastitis control in herd 1?

Answer 29

• Dry cow therapy
• Straw bedding management
• Hygiene of dry cow shed
• Ventilation of dry cow shed
• Internal teat sealants

Question 30

What other interventions are important for mastitis control?

Answer 30

• Parlour routine
• Cubicle comfort
• Dry cow therapy
• Straw bedding management
• Hygiene of dry cow shed
• Wearing gloves during milking
• Ventilation of dry cow shed
• Pasture management
• Treating High SCC cows
• Internal teat sealants

Question 31

Discuss pasture rotation and dry cow mastitis?

Answer 31

Pasture rotation
(far off dry cows in this herd were only ones that went out to graze so in this herd not as useful)
Rule of graze 2 weeks then rest 4 weeks.

Dry cows often get left on the same pasture for long periods of time so this is important to think about.

Question 32

Look at herd 2 stats?

Answer 32

• 120 cow H/F Herd
• Year-round calving
• Cows graze in the summer and housed in winter
• Far-offs graze in the summer
• Transition cows housed all year round (straw yard)
• Milked x2 daily in herringbone parlour
• Buys in occasional replacements and bulls
• Vaccinates for Lepto

Question 33

For herd 2 the average BMSCC for the last 12 months was 350,000 cells/ml. How does this compare with the national average?

Answer 33

Higher

Question 34

True or false

Contagious pathogens usually result in an increased prevalence of subclinical infections and an increased prevalence of chronic infections?

Answer 34

TRUE

This is because pathogens that invade contagiously are passed from cow to cow and as a result of these infections we tend to see infections that stick around; live in the cows udder and udder adaptive and makes them difficult to get rid of.

Cows find it difficult to get rid of the contagious ones as unlike the environmental ones which are opportunistic they are often already in the udder and therefore are able to persist in the udder chronically.

In reality there will be a mixture of both but we need to focus on the one that is causing more problem

Question 35

The summary for herd 2 is:

• High BMSCC
• High incidence CM
• High prevalence of subclinical infections
• High prevalence of chronic infections
• Low dry period cure rate
• A lot of recurrent infections

What is your diagnosis?

Answer 35

Contagious Lactation

The only way contagious pathogen can be passed from cow to cow is in the milking parlour as there is very little opportunity for spread from cow to cow in dry period.

Question 36

How do we reduce risk of contagious lactation?

Answer 36

5 point plan

Question 37

Which 5 elements comprise the 5-point plan?

Answer 37

1. Post milking teat disinfection (Contagious important getting rid of bugs left on teat skin after milking it may get from the cluster)
2. Blanket dry cow therapy most effective in contagious herds (think of antibiotic resistance though)
3. Culling of problem cows
4. Milking machine maintenance
5. Treatment of clinical cases

Vast majority have more problems with environmental nowadays and this plan is more appropriate for the contagious herds which are not seen as often

Question 38

What is the AHDB mastitis control plan
main principle of scheme?

Answer 38

Detailed individual risk base farm approach

Software helps identify shortcomings in management about the problem found allowing for a holistic individual farm based approach

Highlights management changes most relevant to problem found