Mastitis Flashcards
The dairy industry has equated the number of somatic cells in milk to?
the presence of bacteria in milk and the udder
What is different about SCC in goats?
Factors other than bacterial infection accounted for 48% variation observed in the SCC of goat milk
How is milk secreted in goats?
Milk is produced via aprocrine secretion. During the secretion of milk, a portion of the cell membrane is pinched off. This vesicle may contain DNA and as such maybe counted, depending on the counting method, as a somatic cell. Also, there are a number of epithelial cells sloughed off into milk
How is milk secreted in cattle?
Milk secretion in cattle is via merocrine secretion, in this case, the milk products are secreted from the cell via exocytosis.
How is milk secreted in sheep?
Although secretion in sheep is classified as merocrine, ovine milk may contain some cytoplasmic vesicles but not nearly the same amount as goats
What is the legal limit of SCC in goats?
1,000,000 cells
How are SCC determined?
Fossomatic electronic cell counter can be used but must be calibrated with goat milk. The preferred stain for goat milk is pyronin green stain.
What is another factor affecting SCC in goat milk?
cell type - the predominate cell type is the neutrophil compared to the lymphocyte/monocyte in bovine milk and ovine milk
Neutrophils likely increase as _ increases
DIM
Why do goats have high neutrophil counts?
as a protective mechanism against clinical mastitis
What else can influence the SCC?
Parity- freshened doelings had the lowest counts and counts increase with with subsequent lactations, mainly increase in neutrophils
What trend do we see with SCC and DIM
There is an increase in SCC as DIM increase, especially towards the end of lacation
What influence does estrus have on SCC?
In goats, estrogen increases epithelial generation and exfoliation. Thus, epithelial cells are the main reason the SCC goes up compared to cattle and sheeep.
-small ruminants are at the end of their lacation when breeding occurs. Also, there is a decrease in feed consumption resulting in a reduction in milk output.
In cattle, when will SCC be lower?
morning milking compared to the evening milking. The opposite is true for sheep.
What viral infections are common in ruminants?
What viruses affect each species?
Lentiviral infections.
Enzootic Bovine Leukosis occurs in cattle, ovine progressive pneumonia in sheep, caprine encephalitis arithritis in goats.
Sheep and goats serologically positive for OPP and CAE have _ SCC compared to their negative herd mates
Increased
Is there a difference in SCC for hand milking vs machine milking?
No
What has the greatest impact on SCC
Infection
What are the most common organisms to cause mastitis?
Staphylococcus
-remove animals with S. aeureus and possibly chronic infections
What is the most commonly isolated CNS in goats?
What about sheep?
S. epidermidis and S.caprae
S.epidermidids and S.simulans
dry treatment should contain a product with novobiocin
What bacteria are not as prevalent in small ruminants compared to cattle
Streptococcal
Do coliforms cause mastitis in small ruminants?
Although isolated from the udder, it doesnt seem to cause the problems it does in the bovine
What can manheimmia hemolytica cause in nursing ewes
gangrenous mastitis
Contagious agalactia syndrome
produced by mycoplasma species is observed in sheep and goat dairies. Common clincila signs are a watery mastitis that turns to a purulent thick secretion. Some animals may develop a hard agalactic udder. These organisms may cause a subclincial infeciton resuldingin reduced milk production and increased SCCs. More importantly, milk fed to kids may result in severe pneumonia, arthrisi, and a fatal sepitcemia. Treatment is generally infecctive
How do we diagnose clinical mastitis in small ruminants?
change of milk consistence and presence of gargot.
-SCC arent very useful in detecting intramammary infections -especially goats
California mastitis test score of trace or 1 in small ruminants?
normal flora for small ruminant milk
Milk that scores 2 or 3
should be considered for culture
Because previous mammary infections may result in fibrosis of the udder resulting in reduce mlk production and subclinicla infecitons, udders should be palpated for hard areas prior to breeding. What about females with detectable areas of fibrosis?
-should be culled as they may not produce adequate milk yields and may develop mastitis from a subclinicla infeciton
How can we prevent intramammary infections?
proper milking technique
Milking vacuum level?
10-10.6 low line, bucket system
10.6-11.2 high line system
Pulsation
70-100 pulsations a minute
What is the proper milking procedure
-clean teats with individual towels
-strip teats to examine milk
-apply milking unit within 30 seconds of cleaning teats to capture proper oxytocin release milk let down
-remove all the milk from the udder
-turn off the vaccum to teat before removing unit
-apply teat dip after completion of milking or removal of milking unit
