Mastitis Flashcards
Environmental mastitis pathogens
E.coli
Streptococcus uberis
Klebsiella
Contagious mastitis pathogens
Streptococcus uberis Streptococcus dysgalactiae Streptococcus agalactiae Staphylococcus aureus Coagulase negative staphylococci Mycoplasma
How does sub-clinical mastitis present?
No visible signs
Changes in SCC
Reduced milk quality and yield
How can you grade clinical mastitis?
1a - mild changes in the milk
1b - acute milk changes + udder hot and painful
2c - chronic changes in milk + udder hard and lumpy
3 - changes in the milk and udder + cow sick
What are the outcomes of mastitis infection?
- Clear the infection and return to normal milk production
- Persistently infected - spreads amongst the heard
- Permanent damage to the udder causes a reduced milk yield
- Death - toxaemia
How can the the teat skin be damaged to predispose a cow to mastitis? And how can you protect the teat skin?
Bruising, chapping, trauma
Teat lesions
Damage by the milking machine
Methods to protect the teat skin:
- post-milking teat dipping
- prompt treatment of teat lesions
- good milking machine function
When can bacteria invade the teat canal? And how is the teat canal damaged?
When open during and after milking - takes about 20-30 minutes to close
Keratin forms a seal over the teat end when the cow is dried off
Damage to the teat canal occurs by:
- milking machines
- trauma to the teats
- teat lesions
- teat cannula
What causes Teat end hyper keratosis?
Excessive milking vacuums
Worn teat liners
Faulty pulsations
Liner type
When are cows at most risk of acquiring new mastitis infections?
Early dry period
Late dry period
When do most clinical mastitis cases occur?
1st 6 weeks post calving
Why are cows predisposed to acquiring mastitis infections in the dry period?
Cessation of milking - increased intra-mammary pressure and widening of the teat canal Bacteria not flushed out No teat dipping Poor formation of the keratin plug WBC function is reduced
What nutrition factors can lead to mastitis?
Negative energy balance
Vitamin E and Selenium
Sub-acute Rumenal Acidosis
Hypocalcaemia
What does the mastitis vaccine protect against?
Staph aureus
Coliforms
Coagulase negative staphylococci
What are the housing requirements for a cow?
Lying area Loading area Feed space Safe flooring and passageways Water supply Slurry handling
How much loafing area should cows have?
120% of cubicle area
How much feed barrier space must a cow have?
60cm per milking cow
90 cm per dry cow
How much water space must a cow have?
10cm per cow
How much lunge space does a cow need?
0.7 - 1m lunge space
What does the stack effect require?
Inlet above the outlet
Sufficient body mass to generate heat to move the air
5 freedoms
Freedom from hunger and thirst Freedom from pain injury and disease Freedom from discomfort Freedom to express normal behaviour Freedom from fear and distress
What lighting should you provide for cows?
16-18 hours per day
Increases yield by 2 L
10% of the roof area should be transparent
What is the stocking density of loose housing?
1.3 m squared / 1000 kg of herd milk production
What are advantages and disadvantages of loose cow housing?
Comfortable so reduced lameness
Increased requirement for trimming
Straw is expensive
Increases Streptococcus uberis risk
Poor hygiene
High cell counts
How should you maintain loose straw housing?
Clean out every 2 weeks
Bale down 3 times a week
Store dry bedding under cover
Have a sand drainage layer that can be replaced every few months
Completely clean out straw every 2 weeks
Clear divide between bedding and standing
When should a farmer increase cleaning frequency?
Disease
Squelching
Bedding hot to touch
What is minimum water requirement of a cow?
15-20L
What should you aim to deliver in a cubicle design?
Comfortable lying and standing time
Slight curb incline kerb-front
Dung passed over the kerb with minimum deposited on the rear
Minimise pathogen growth with the choice of bedding
How long should a cubicle be?
2.3-2.4m
Height of the head rail
1.4m
What width of a cubicle is there?
1.15 - 1.2m
What should the kerb height be?
10cm
What slope kerb should you have on a cubicle?
2-3%
What lying length should you have in a cubicle?
1.7m
What disease will you see with poor cubicle design?
Lameness
Mastitis
Neck lesions - feed barrier
Hock and stifles - problems with bedding
What does a cow reverse into a cubicle tell you?
Too high a kerb
What does a cow standing with its hind feet in the passageway tell you?
Head rail too near kerb
What does a cow lying diagonally in the cubicle tell you?
Cubicles too wide
What is the cow comfort quotient?
Number of cows correctly interacting with the cubicle /
Number of cows interacting with a cubicle at all
X 100
Aim for over 80%
Less than 50% poor
What do hock lesions indicate?
Insufficient substrate
Cubicle too short
Cubicles with solid rear leg supports
Poor quality shavings
What does a half in half out posture predispose to?
Solar ulcers
What does standing time in slurry cause?
Heel horn erosion and digital dermatitis
What does dung, urine and milk deposited on the cubicle predispose to?
Environmental mastitis
How much substrate should a cubicle have?
3kg per day
What are the advantages and disadvantages of substrates?
Sand = best - hygienic
Deep straw = streptococcus uberis risk
Paper ash = hardens when wet
How frequently should scrapers be run?
Every couple of hours
How can you design a building to maximise comfort?
2 rows of cubicles per feed barrier
3m passage between rows of cubicles
4.3m passage between a row of cubicles and feed barrier space
2.4 passageway between rows of 20 cubicles
How can you ensure cow comfort during feeding?
Adequate feed rail height and feed barrier offset forwards Palatable feed Keep feed pushed up and within reach Brushes - enrichment Sprinklers to cool
How can you ensure good ventilation?
3/4 inch gaps between roof slots
Fans
Open ridge plus chimney
What pressure should the milking vacuum be regulated at?
42-48 kpa
What speed should the vaccum pulsator be set at?
60 pulsations per minute
What is the vaccum on to off ratio?
2:1
How does the milking machine contribute to mastitis?
Damage to the teat ends
Acts as a vectors for spread of mastitis
How does damage to the teat skin occur during milking?
Worn / hard liners
Inadequate rest phase in pulsators or pulsations too fast
Excess vacuum
Inadequate emolient in the post-dip
What leads to teat sphincter hyperkeratosis?
Excess vacuum Fluctuating vacuums Over-milking Faulty liners Poor pre-milking teat preparation - not enough milk let down
How does the milking machine transfer mastitis infection?
Contamination of liners
Wet milking
- Inadequate vacuum
- Fluctuating vacuum
- Blocked air bleed
What common problems are encountered with milking machines?
Vacuum problems - hissing sound
Fluctuating / inadequate vacuum - holes in tubing, liner slip
Blocked air bleeds on the cluster unit - flooding of the claw piece
Faulty pulsation - too fast, inadequate rest phase, holes in tubing
What simple tests can you perform to assess the function of the milking machine?
Examine the cluster
- blocked air bleed
- cleanliness of liners
- wear of liners
- perishing holes in tubing
Note the level of the vacuum gage - 42-48 Watch whilst milking - liner slip - need smaller liner - oedematous teats - need a bigger liner Watch cows - paddling or kicking Teat score Ask wash up routine Ask when last serviced
What factors should asses in the parlour routine?
Gloves
Pre-milking teat preparation - fore-milking, teat disinfection
Post-milking teat preparation
Loafing time
Parlours management - milking order, cluster disinfection
Parlour wash up routine
What does fore-milking do?
Legal requirement
Milk let down
Allows early detection of mastitis
What benefits does teat cleaning and disinfection have?
Reduces environmental bacterial contamination
Stimulates let down
Reduce the risk of strep uberis and e.coli
Good for public health
What are some common teat disinfectants and what should you check regarding their use?
Chlorhexidine
Iodophors
Concentration
Contact time
Teat coverage
How can you assess the effective of teat cleaning and disinfection?
Milk filter analysis / bacteriology
What does pre-milking cleaning and disinfection prevent?
Environmental mastitis
What does post-milking teat disinfection prevent?
Contagious mastitis
- staph aures, strep dysgalactiae, strep agalactiae
Disinfectants - iodine, chlorhexidine, lactic acid
Emollients
Dye
Sticking agents
How can post-milking teat dips be applied?
Dip pot - can spread infection is disinfectant is ineffective
Spray
Cluster
How much loading time should a cow have to allow for the teat sphincter to close?
30 minutes
Prevents environmental infections
Allows closure of the teat sphincter
Keep in a clean area
What milking order should you recommend to a farmer?
Heifers Fresh calvers High yielders Low yielders High cell count cows Mastitic cows
STILL NEED TO DISINFECT THE CLUSTER BETWEEN COWS
How should a farmer manage high cell count and mastitic cows?
Red tail tape
Milk last in the order
Clean and disinfect the cluster between each cow
What parlour wash routine should you recommend?
Clean milk out of the clusters Cold rinse Hot wash - more than 60c for clusters, 85-90c for tank - 10-12L of water Rinse with hypochlorite Acid and alkali washes
How can you assess the efficacy of the milking parlour in preventing mastitis?
Milking machine assessment
- observe cows, observe vacuum gage, listen for liner slip
Teat score a minimum of 20% of the herd
Observe parlour hygiene routines
Management of high cell count cows and mastitic cows
Parlour wash routine
Take milk samples for bacteriology
IWhat is the mastitis 5 point control plan?
- Post milking teat disinfection
- Dry cow therapy - intra-mammary tubes and teat sealants
- Prompt treatment of clinical cases
- Cull chronic cases
- Maintain and use the milking machine properly
Effective at control CONTAGIOUS mastitis, but not effective for controlling environmental mastitis
What are the most common causative agents of mastitis?
Streptococcus uberis - contagious and environmental
E.coli - environmental
Staphylococcus aureus - contagious
Online a mastitis action plan.
Housing - dry, clean and well ventilated Good parlour routine - wearing gloves - pre milking and teat disinfection - good milking machine maintenance - post-milking teat disinfection - loafing time - maintain good teat condition - good milking order Dry cow management - therapy, housing, nutrition Nutrition - avoid SARA, NEB, provide vit E and selenium Prevent milk fever Cull chronic cases Regular monitoring Fly control Good record keeping
How should you control contagious mastitis pathogens?
Control spread during milking
- post milking teat dipping
- properly functioning milking machine
- milking order
- disinfect cluster
Reduce levels of infection in the herd by treating clinical cases
- strep agalactiae and dysgalactiae - penicillin sensitive
- dry cow therapy
- staphylococcus aureus is more difficult to control
How should you approach treating cases of staphylococcus aureus mastitis?
Need to treat for longer periods - lives intra-cellularly
Culture and sensitivity required - 1/3 penicillin resistant
Infections occurring at the end of lactation
- dry off early
- intra-mammary Ab +/- systemic antibiotics
Infections occurring during lactation
- 5-8 days of intra-mammary antibiotics
- systemic antibiotics
Cull chronic cases
When do E.coli infections normally present?
Most infections acquired in the dry period and early lactation
Hygiene during these periods is essential
What factors can you control to decrease the incidence of E.coli mastitis?
Housing hygiene and comfort - especially dry, fresh calved and early lactation
Pre-milking teat disinfection - high concentration of iodine
Loafing times - 30 minutes
Dry cow management - nutrition, therapy
Startvac vaccine
What measures can you take to control Strep uberis mastitis?
Often picked up in dry period and early lactation
Step uberis acts as both a contagious and environmental pathogen
Housing - dry period and early lactation Pre-milking teat disinfection Loafing times Effective therapy Dry cow management Parlour hygiene
What statistics can you look at when assessing a herd mastitis problem?
Number of clinical cases per 100 cows per year % herd affected Recurrence rate Seasonality Stage of lactation
What is the sensitivity of bacterial culture vs PCR?
70% bacterial culture
92% PCR
What should you assess with hygiene scoring?
Cleanliness of the cow
- below the hock
- upper leg and flank
- udder
Less than 25% scores 3 or 4
What scoring methods can you use to assess nutrition?
Condition scores
Faecal scores
Look at the diet
What percentage of the herd should you teat score?
At least 25%
What can you advise a farmer to reduce their SCC so they can still sell their milk?
Identify the worst affected cows and remove their milk from the bulk tank
How can you select an individual cow for bacteriology testing?
Clinical cases
High SCC cows
What factors should you consider when investigating a contagious mastitis problem?
Poor parlour hygiene
Transmission by the milking machine
Poor management of high cell count cows and clinical cases
Ineffective dry cow and lactating cow therapies
What factors should you consider when dealing with an environmental mastitis problem?
Bad housing Poor parlour hygiene Dry cow management Dry cow therapy Insufficient teat preparation
What systemic disease can cause teat lesions?
Foot and mouth disease
Malignant catarrhal fever
Photosensitisation
What infectious teat lesions are there?
Warts - bovine papilloma virus Pseudo cowpox Bovine herpes mammilitis Black spot Cow pox Udder impetigo
What non-infectious teat lesions are there?
Photosensitisation Chapped teats Cut teats Teat pea Teat stenosis Blind teats
How can you diagnose teat lesions?
Dry scabs for electron microscopy
Bovine herpes mammilitis serology
What is the general treatment for teat lesions?
Teat cannula - to allow milk drainage
Intra-mammary antibiotics
Emollients
Antiseptics
Teat warts / bovine papillomatosis
Bovine papilloma virus
Seen in young heifers
Spread by files
- harbour bacteria - predispose to mastitis
- cause poor liner attachment - teat end impacts and difficulty milking
- pain
Tx: most self cure
Can be removed by laser or cryo
Autogenous vaccine for severe cases
Prevention - fly control - synthetic pyrethroid ear tags / pour ons, permethrin
Pseudo cowpox
Parapox virus
Curricular, or horse shoe shaped non-painful scabby lesions
Spreads throughout the herd
Tx: post-milking teat dipping
Self cure but may recurr
Bovine herpes mammilitis
Bovine herpes virus 2
VERY PAINFUL TEAT ULCERS
Slow to heal - takes weeks - immunity once healed
Seen in 1st lactation heifers
Transmission via contaminated clusters
Treatment: improve parlour hygiene
Acyclovir
Cow pox
Last occured in 1978
Orthopox virus
Spread by cats
Lesions appear the same as bovine herpes virus
- very painful and slow healing
Black spot
Excessive vaccum causes blue teats and teat end eversion
- predisposes to Fusobacterium necrophorum infection
Causes black spots on teats
Treatment: adjust the vacuum
Oxytetracycline spray
Teat cannula - check the milking machine
Udder or teat impetigo
Staphylococcus aureus
Pustular lesions on the teat and udder skin
Can spread to milkers
Control: post milking teat dipping, antiseptic creams
Photosensitisation and sunburn
The teats are usually the first place to show Photosensitisation
Ingestion of photosensitising plants - St John’s wart
Liver disease - chronic fluke, ragwort ingestion
Tx: remove from sunlight, NSAIDs supportive treatment
Chapped teats
Painful
Poor teat skin care - no emollients in dips
Worn liners
Calf sucking
Tx: emollients and place a teat cannula so you don’t have to put the cluster on
What is required of a post-milking teat dip?
Correct anti-septic to kill contagious mastitis pathogens
Emolient
Persists on the teat for 30mins (loafing time)
Teat pea
Pedunculated granuloma attached to the wall of the teat canal - blocks milk flow
Treatment - removal by hudsons spiral
- rotating up the end of the teat canal to pull out granuloma
- granuloma milked out
- place a teat canal
MUST GIVE PROPHYLACTIC ANTIBIOTICS TO PREVENT MASTITIS
Teat stenosis
Usually secondary to trauma or summer mastitis
Guarded prognosis - scar may reform
Tx: sedation and local anaesthetic - painful
use a teat knife to open up the teat canal
teat cannula
Blind teats in heifers
Should be left alone - there is no milk in there
How should you treat a teat laceration?
Sedate with xylazine
Restrain in a foot trimming crush and raise leg
Clean teat and wound thoroughly
Apply a local anaesthetic nerve block - teat lumen block / ring block
If very superficial - glue
Clean and debride
Close subcutaneous layer with a continuous suture
Suture skin with a simple interrupted pattern (vertical mattress in diagram)
Guarded prognosis - may lead to teat stenosis
How can you treat supernumerary teats in a calf under 2 months old?
At the same time as disbudding
Put in a dog sitting position and hobble the hindlimbs
Can be removed with scissors without local anaesthetic
How can you remove a supernumerary teat in an older calf?
Crush and lift leg
Or sedate and cast and apply kick bar
Do in parlour
Give local anaesthetic
Remove with scissors or emasculators
How can you know how much sub-clinical mastitis there is in a herd?
California milk test
Milk recording
If you are going to submit a milk filter for bacteriology, what must you do first?
Remove it at the end of milking, before the wash cycle
What cell counts does the California milk test go positive for?
Over 300,000 cells
What things can you assess when investigating mastitis?
In parlour
- fore milking - visible milk changes
- clinical signs - palpation, cow response, cow health
- California milk test
- in line filters - submit for bacteriology
Clinical case records
- get farmer to make a table and record
Cow ID, date, quarter affected, treatment, cell count at 7 days
Somatic cell counts - individual or pooled
- a few counts contribute to most of the cell count
- want to identify these cows and exclude them from the bulk tank
Bulk tank bactoscan
Bacteriology - individual or bulk tanks
Multiplex PCR - more sensitive, used to identify penicillin resistant staphylococcus aureus
What is the target for number of clinical cases per year?
Less than 30 cases per 100 cows per year
Average 45-60
What is the target for annual incidence of mastitis?
Less than 20% of herd affected
What is the target for recurrence rate of clinical mastitis?
Less than 10% of cases recurr
What does a high recurrence rate (over 10%) suggest?
Staphylococcus aureus
Streptococcus uberis
Problems with treatment - eg penicillin resistance in S. aureus
Teat end damage
What should be a farmers target milking cow intra-mammary antibiotic use age?
Less than 140 per 100 cows
What do milk recording systems record?
On a monthly basis
High cell count cows
Chronically infected cows
Stage of lactation
How can you determine which cows are affected based on individual SCC?
Under 100,000 - infection unlikely
100,000 - 200,000 - infection in one quarter with minor pathogen
200,000 - infection in quarter with major pathogen
How can you quickly fix a bulk milk tank result over 400,000?
Prevent milk from high cell count cows entering the tank
- identify individual cows using NMR results
- California milk test in parlour - identifies cows over 300,000
What does a high bactoscan result indicate?
High bacteria numbers in milk
- high levels of mastitis
- poor plant cleaning
- dirty udder / teats - insufficient pre-milking teat preparation
- poor housing hygiene
What level of bactoscan will the milk be excluded from supply?
Exceeding 50,000
What must you ensure when transporting bulk milk samples for bacteriology?
Keep sample cool on ice
What can results from bulk tank bacteriology tell you?
Total bacterial count
Cell count
LPC thermoduric count - cleanliness of the plant
Coliform count - adequacy of pre milking teat preparation
Total staphylococcal count
Staphylococcus aureus
Strep uberis, dysgalactiae and agalactiae
What should you advise a farmer to do with his clinical mastitis cases and high cell count cows before treatment?
Take sterile milk samples, freeze and submit for bacteriology and culture and sensitivity
Keep a rolling 12 months of samples in the freezer - culture some occasional when there is a problem
Hat are the main limitations of individual cow bacteriology?
Some pathogens are only intermittently shed - S. aureus
Contaminated samples
Some animals that have received antibiotic treatment show no growth (last 7 days)
What should you do if there is no growth on bacteriology?
Repeat sampling
PCR
How can you interpret bacteriology results?
Pure growth of bacteria - causal
Major pathogen and minor pathogen - major causal
More than one minor pathogen - mixed infection
More than 3 bacteria present - contamination
Negative - intermittently shedding or on antibiotics
What would you suspect as a causative agent if you have chronically high SCC?
Gram positive causative agent
Eg: staph aureus
What would you suspect as the causative agent when there is a quick spike in SCC followed by recovery?
Gram negative
What would you expect if you had lots of clinical cases occurring in the first month post-calving?
Infection picked up in the dry period
What would you expect if you had lots of clinical cases but low herd SCC?
Gram -ve
How does staphylococcus aureus appear on culture?
Gram positive cocci
Coagulase positive
Forms white colonies on blood agar, with a ring of haemolysis
Intra-cellular bacteria, produces abscesses = recurrent
- intermittent shedding
1/3 of strains produce beta lactamases - penicillin resistant
What is the most common contagious mastitis pathogen?
Staphylococcus aureus
How does staphylococcus aureus mastitis present?
Sub-clinical - persistently high SCC
Clinical grade 2a (acute) - udder, hot swollen and painful
Clinical grade 2c (chronic) - abscess formation and fibrosis
Clinical grade 3 (gangrenous) - systemically ill cow
How does gangrenous mastitis due to staph aureus present?
Freshly calved (immunosuppressed) Systemically ill - toxaemic Gangrene of udder tissue Udder cold, blue and necrotic Milk often dark red and bloody
How should you treat gangrenous mastitis?
IVFT - 5L 7.2% NaCl, followed by 4x15L buckets of water NSAIDs - ketoprofen, meloxicam Strip out affected quarter Oxytocin Systemic antibiotics
Consider PTS
What are poor prognostic indicators in staph aureus mastitis?
Older cows, more than 5 lactations
3 or more repeat infections
Chronically high SCC
Penicillin resistance
How can you control staph aureus mastitis in a herd?
Treat cases
Cull chronic cows (3 or more cases)
Dry cow therapy
Check any introduced animals - SCC, examine udder
Good parlour hygiene
- wear gloves
- do not use a common udder cloth
- early detection and treatment
- post-milking teat disinfection
- mastitic cows or chronic high cell counts milked last
- maintain the milking machine correctly - liners and vacuums
How can you identify streptococcus agalactiae on culture?
Gram positive cocci
Non-haemolytic
Very small pin prick colonies
What stages of mastitis does streptococcus agalactiae cause?
Sub clinical - high SCC
Grade 1 - mild milk changes
Grade 2 - hot, hard, swollen udder, mild milk changes
How can you treat streptococcus agalactiae?
Intra-mammary penicillin
Blitz therapy to eliminate from the herd
How does streptococcus dysgalactiae appear on culture?
Gram positive cocci
Small pin prick colonies on Edwards Medium
Partial haemolysis, green zone
Alpha haemolysis
What type of mastitis does streptococcus dysgalactiae cause?
Part of summer mastitis
Persistent infections
Usually associated with teat condition and milking pulsator problems
How can you treat streptococcus dysgalactiae?
Responds well to penicillin
Address problems with the milking machine - vacuum / pulsator problems
How does mycoplasma mastitis usually present?
M. bovis, M. californicum
- m.bovis also causes infertility, metritis, joint ill and otitis media, keratoconjunctivitis and pneumonia
(Don’t feed milk to calves)
Marked milk drop
Swollen quarter
Cow not systemically ill
Highly contagious in the parlour and aerosol spread
How can you treat mycoplasma mastitis?
Poor response to antibiotics - no cell wall Milked last and cluster disinfected Or cull - destroys the quarter - pathogen may be shed for life
What should you consider of you culture coagulase negative staphylococci?
Minor pathogen - may be a skin contaminant in a milk sample
Mild disease that causes high SCC
Repeat culture
Tx: spontaneous cure frequent
Respond well to penicillin
How does E.coli appear on culture?
Gram negative rods
Creamy white colonies on blood agar
Haemolytic and non-haemolytic
Metallic green sheen on Eosin Methylene Blue
What grades of mastitis does E.coli cause?
Clinical cases often seen during the 6 weeks of lactation - infections acquire during the dry and periparturient period
Bacteria produces LPS endotoxin = damage to secretory and vascular tissue
Grade 1 - clots in milk - self cure Grade 2 - clots in milk, hot hard and painful udder Grade 3 - common = toxic mastitis - very sick, in endotoxaemic shock - variable udder consistency - milk varies from clots to blood IMPORTANT DDX IN DOWNER COW POST-CALVING
How should you treat grade 1 and 2 E.coli mastitis?
Self cure
Or intra-mammary antibiotic eg aminoglycosides
How should you treat a grade 3 toxic e.coli mastitis?
3-5L of 7.2% NaCl IV, followed by 4 x 15L buckets of water
NSAIDs - ketoprofen, meloxicam, flunixin
Strip out quarter q 4-6 h
Oxytocin
Intra-mammary antibiotics - trimethoprim sulphonamides, aminoglycoside
Systemic antibiotics - oxytetracycline
How can a farmer control E.coli mastitis in his herd?
Important - infection occurs in dry period and early lactation
Improved housing hygiene and nutrition
Pre-milking teat disinfection
Clean loafing area for 30mins after milking
Dry cow therapy - aminoglycoside and teat sealant
Startvac vaccination
What does startvac protect against and when should it be given?
3 doses
- 45 days pre-calving
- 10 days before calving
- 7-8 weeks post calving
E.coli, staph aureus, coliforms, coagulase negative staphylococci
Reduces the incidence of subclinical mastitis
Reduces the incidence and severity of clinical mastitis
How does streptococcus uberis appear on culture?
Non-haemolytic
Brown colonies on Edwards medium
Gram positive cocci - chains
Blood agar - Alfa haemolytic colonies
What clinical presentations does streptococcus uberis mastitis cause?
Straw bedding
(Environmental and contagious)
All grades of mastitis can occur
Sub clinical infection common - high SCC
Chronic and recurrent infections are common
How should you treat strep uberis mastitis?
Can be difficult to eliminate from the udder
Intra-mammary - penicillin (penethamate good penetration)
Systemic antibiotics - tylosin (macrolide)
Dry off early with antibiotics if nearing end of lactation
Cull chronic cases
How does klebsiella present?
Sawdust bedding / dirty parlour wash
Acute mastitis - appears very similar to E.coli
How does bacillus cereus and lichenoformis present?
Environmental from Brewers grains, dirty parlour wash
Acute mastitis
How does pseudomonas present?
Sawdust / dirty parlour wash, poor hygiene when administering intra-mammary tubes
Acute mastitis
Difficult to treat
How does mastitis caused by yeasts present?
Sporadic
Wet mouldy bedding, teats washed before milking but not dried
Poor hygiene
How does summer mastitis present?
Dry cows and heifers outdoors in the summer
May also occur in housed cattle in the winter
What are the causative agents of summer mastitis?
Truperella pyogenes Fusobacterium necrophorum Streptococcus uberis Bacteroides melaninogeneicus Peptococcus indolicus
Spread by hydrotea irritans
How does summer mastitis typically present?
Hot, hard, very painful, swollen udder
Thick purulent secretion
Cow systemically ill
May be lame
Mild cases occur that are only noticed when the cow is calved down
- Truperella pyogenes cultured
How should you treat summer mastitis?
REMOVE ANIMAL FROM GROUP TO PREVENT SPREAD
Cull - Poor response to antibiotics, forms abscesses in the quarter and irreparably damages the udder
How can you prevent summer mastitis?
Fly control - SP tags in each ear, apply fly repellent to udder weekly
Seal teats with tape
House animals
Move away from woodland
Increase dry cow therapy to every 3 weeks
What animals should you milk sample?
Bulk sampling
Next 10 cows that have clinical case
High SCC cows
Cows that do not respond to treatment
What is the cut off SCC when a farmer is no longer allowed to sell their milk?
Over 400,000
Most milk companies will not buy if over 200,000
How can you assess whether there are repeat infections?
Ask the farmer to make a 2x2 grid
Record quarter treated and date
Can see whether there has been repeat infections
What can a bactoscan tell you?
Coliform count - inadequate pre milking teat disinfection
Thermoduric count - inadequate plant cleaning
Physcotroph count - poor hygiene, refrigeration and contaminated bedding
What does a high bactoscan result but a low SCC suggest?
Plant problem, not mastitis
What antibiotics should you choose for a gram positive mastitis infection?
Beta lactams intra-mammary - penicillins, cephalosporins
Macrolides systemic - Tylosin
- for chronic S.aureus and Strep.uberis infections
What intra-mammary antibiotic should you use for gram negative infections?
Aminoglycosides
May not need to use anything - self resolves
What intramammary antibiotic should you use for a mixed infection?
Trimethoprim potentiated sulphonamides
What antibiotics are there no intra-mammary antibiotics for?
Fluoroquinolones
Florfenicols
Tetracyclines
What antibiotics should you use in a hot, hard, udder where there is not culture and sensitivity results?
Broad spectrum antibiotics - you’ll be in trouble with rob smith!
TMPS
Pen and gent - penicillin and aminoglycosides
Cephalosporins
What products are in the commercial Intra-mammary tubes?
Duo fast - TMPS (toxic mastitis)
Tetra-delta - aminoglycosides (streptomycin, neomycin) + prednisolone
Multi-ject - penicillin + aminoglycosides (streptomycin and neomycin) + prednisolone
Synulox - potentiated amoxicillin - resistant S.aureus
Ubrolexin - aminoglycoside (kanamycin) and cephalosporin (cephalexin)
What causes a high SCC one month post-calving?
Gram negatives - E.coli, Klebsiella
What causes a continuously fluctuating SCC?
S.aureus
What causes a high SCC which responds well to treatment?
Strep agalactiae and strep dysgalactiae
How can you tell whether mastitis has been cured or not?
SCC <100,000 twice, or <200,000 three times
California milk test
When are bulk milk tank cell counts determined?
Every time the milk is collected
When are individual cow cell counts determined?
Monthly
What kind of cell count level will you see with E.coli mastitis?
400,000 - 800,000
What kind of cell count will you see with S.aureus / strep.uberis mastitis?
> 1,000,000 very high chronic cell counts
How many days in milk should you consider drying a cow off early if they have clinical mastitis / high SCC?
Over 300 days in milk
What are the 1st line intra-mammary tubes?
Multiject - penicillin + ag (streptomycin + neomycin) + pred
UBRO yellow - penethamate (penicillin) + streptomycin + framomycin + pred
Tetra-delta - penicillin + streptomycin + neomycin + pred
Pathocef - cefoperazone
Mastiplan - Cefapirin
Ubrolexin - cefalexin
What are you second line intra-mammary tubes?
Synulox - amoxicillin clavulanic acid
Cobactan - cefquinome
How long should a farmer leave between fore-milking and placing the cluster?
45-90 seconds
When should change liners?
When there is signs of wear
Squeaking sounds
Every 2500 uses - every 90 days at Woodpark
When cell counts are increasing
What is the minimum number of services a milking machine should have?
Once a year
How should you disinfect the cluster between high SCC cows and mastitic cows?
Rinse and spray with acetic acid
What should you perform on a high SCC cow?
California milk test - shows what quarters are affected
What should you give every case of mastitis?
Nsaid!!! Ketofen
How does Truepurella pyogenes appear on culture?
Haemolytic colonies on blood agar
Gram +ve rod
How does klebsiella appear on nutrient agar?
Large mucoid colonies
Gram -ve rod
How does pseudomonas appear on nutrient agar?
Green pigmentation on nutrient agar
Gram negative rod
