Mastitis Flashcards
How does mastitis cause money loss?
- decreased milk production
- costs associated with clinical disease
- increased SCC
What is somatic cell count?
indicator of mammary gland inflammation
linked to decreased milk shelf life and cheese yeld
What is the regulatory limit of SCC in canada?
400 000 cells/ml
What is the limit of bacteria in canada?
50 000 bacteria/ml
What are the clinical signs of mastitis?
mild: abnormal milk, normal gland, systemically healthy
moderate: abnormal milk, abnormal gland, systemically healthy
severe: abnormal milk and gland, systemically sick
subclinical: increased SCC, destruction of alveoli and ducts, decreased production long term
What are the two groups of mastitis pathogens?
contagious, environmental
What is the reservoir of contagious pathogens?
mammary gland
When are contagious pathgens transmitted?
at milking
What are contagious pathogens?
S. aureus, s agalactiae, mycoplasma, corynebacterium bovis
What is the reservour for environmental pathogens?gens?
environment
What is the transmission of environmental path
between milkings
What are environmental pathogens?
e. coli, s uberis, other coliforms, pseudomonas
What are opportunistsi?
s. dysgalatiae
coagulase negative staph
What is the prevalence of pathogens?
s. aureus most common isolated
e. coli
s. uberis
coagulase negative staph
What are the features of s. aureus?
- most common contagious pathogen
- primarily subclinical (some clinical episodes)
- fluctuating scc and bacterial shedding
- gram positive coccus, coagulase and catalase positive; frequently hemolytic
What are the characteristics of strep agalactiae?
very RARE as it is very sensitive for antibiotics
obligate udder pathogen
subclinical mastitis with periodic flareups
gram positive coccus
catalase negative
What are the features of mycoplasma?
- severe clinical mastitis
- agalactia for rest of lactation
- primarily contagious
- some environmental reservoirs exsit
- young and mature asymptomatic carriers (calves)
What are the features of clinical disease of mycoplasma?
the quarter stops producing milk for rest of lactation
How can mycoplasma access the udder?
systemically (other body sites are affected)
How many species of mycoplasma are there?
at least 5
why should you inform lab you are worried about myoplasma?
because very slow
What are features of corynebacterium bovis?
controlled by teat dip
primarily colonizes teat canal
What are features of prevention and control of mastitis?
a. decrease exposure
b. increase resistance
5 point plan
1. post-milking teat disinfection
2. blanket dry cow therapy
3. clinical mastitis therapy during lactation
4. proper milking machine maintenance
5. cull chronically infected cattle
What is the 5 point plan for mastitis prevention? (will ask this question)
- post-milking teat disinfection
- blanket dry cow therapy
- clinical mastitis therapy duing lactation
- proper millking machine maintenance
- cull chronically infected cattle
What is the most important mastitis prevention step?
post milking teat infection
What are the features of post-milking teat dinsifection?
1. decreases incidence of new IMI by 50-90% iodine chlorhexidine organic acids + emolients- quarternary ammonium sodium hypochlorite
what is the problem with quaternary ammonium?
inactivated by organic material
What is a good feature of chlorhexidine?
it works in presence of organic material
What is the benefit of blanket dry cow therapy?
eliminates infection
prevents infection
Is there a treatment for mycoplasma mastitis?
no
What are the steps in machine maintenance?
- daily equipment inspection
- regular service and parts replacement
- complete machine evaluation (once a year)
What is a chronically infected cow?
- repeated clinical episodes
- repeated positive milk cultures
- high chronic scc
What is the commercial vaccine for staph aureus, e. coli, coagulase negatieve staph?
TOPVAC
How long is the meat withdrawal for TOPVAC
60d
Why don’t contagous mastitis vaccines work?
clearance of mastitis pathogens dependent on presence of sufficient neutrophils
every contagious
high neutrophils = mastitis
mastitis vaccine has to cause mastitis
What is therapeutic cessation of lactation?
infuse udder with povidone-iodine
chlorhexidine
welfare issue!
withhold period not established
Why is it not that useful having cow segregation for separating s. aureus carriers?
hard to ID all animals
What is control measures for mycoplasma?
remove from herd, segregate/milk last
take care when purchasing animals
prevent spread n milking parlour