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19 Cards in this Set
- Front
- Back
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What percentage of milk is water? Solids?
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87%
13% (3.5% protein) |
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What is grade A milk used for? Are most other dairy products like cheese, ice cream etc. also grade A?
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Liquid consumption
Yes |
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Is milk bacteriologically sterile? Where are bacteria located? What type of drug is milk always tested for before unloaded?
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No
Teat canal, outside of teat, mastitis Beta lactam ABs |
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What bacterial test is done routinely by milk processing plant? What must the count be under? If it doesn't pass this what other tests should be done?
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SPC (standard plate count)
< 100,000 cfu/ml LPC- detects thermoduric bacteria PI count- psychotrophic (cold loving) bacteria |
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What four qualities must milk have before leaving the farm?
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1) 45F w/in 2 hrs of collection
2) Somatic cell count < 750,000 3) Bacterial count < 100,000 4) No positive drug residue test |
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When do you sanitize the milking machines? What are the two most common reasons for bacteria in milk?
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No longer than 30 min before milking
Not sufficent cleaning water temperature or volume & dirty teats (outside) |
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What are the five step to cleaning the milking machines?
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1) Pre-rinse
2) Wash (with chlorinated alkaline detergent) 3) Rinse 4) Acid rinse 5) Sanitize |
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Where is it unusual to acquire bacteria that will cause a high bacterial count?
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From the cow
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What does the clarifier remove? What does the separator do?
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Sediment
Separates milk and fat |
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What does brief heating of milk do? Pasteurization is based on killing what pathogen?
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Kills common pathogens
Coxiella burnetii |
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After pasteurization what temperature must it be restored to? What are now the acceptable bacterial levels? Coliforms?
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45F
< 20,000 cfu/ml < 10/ml |
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What is mastitis? What are some organismal causes? In a dairy what percentage of cows will produce abnormal milk?
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Inflammation of the udder
E. coli, Klebsiella, Strep, Staph aureus, Mycoplasma 5-10% |
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In general what kind of cell count do you see with mastitis? Subclinical count? How many do you expect to see with clinical mastitis?
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High somatic cell count and low milk production
SCC >200,000 SCC in the millions with 30% loss in production |
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What is the number one cow side test for mastitis?
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California mastitis test (CMT)
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What are the three classic milk borne pathogens?
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Coxiella burnetii, Brucella, Mycobacterium bovis
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Does Coxiella infect all dairy species? What percentage of farms are infected in US? How are humans infected?
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Yes
> 90% Inhalation, contact with broken skin |
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What species of Brucella infects goats and sheep? Cows? What does it cause in humans? What is it's status in the US?
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B. melitensis
B. abortus Undulant/Malta fever Almost eradicated |
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What percentage of Brucella vax is effective? What happens if a cow tests positive? Who serves a reservoir for Brucella?
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65%
Directly to slaughter Wildlife |
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M. bovis occurs in countries that don't do what?
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Pasteurize
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