(08) Mastitis II

Question 1

(30)

repeat

Question 2

(31)

(Somatic Cells)

1. SCC<!--? considered uninfected?</p-->
2. US legal limit?
3. EU legal limit?

Answer 2

1. 200,000 cells/mL

(cut point determines sensitivty of test)

2 < 750,000 cells/ml

< 400,000 cells/ml (US needs to be this for export)

Question 3

(32)

Answer 3

(33)

Question 4

(34)

Answer 4

(35)

Question 5

(36)

Answer 5

(37)

Question 6

(38)

(California Mastitis Test)

1. test for what?

Answer 6

(39)

Question 7

(40)

Question 8

(41)

(On-Farm Culture)

1. Aseptically collected milk sample are plated, incubated, and interpreted on-farm
2. Fast, inexpensive way to categorize the cause of mastitis into treatment categories:

gram negative, no-growth = ?

gram-positive = ?

3. Limitations?

Answer 8

2. no treat (with exceptions)

treat

3. time, space, personnel, training (does not work well on smaller dairies)

Question 9

(42)

Question 10

(43)

(Culture Negative Results)

1. “no growths” = ?
2. cause of false negatives?
3. cause of true negatives?

Answer 10

1. 25-40% of milk from clinical cases will not grow bacteria

Question 11

(44)

Question 12

(45)

(Bulk Tank Diagnostics)

(SCC)

1 gives a snapshot of what?

varies greatly depending on what?

(Culture)

1. monitoring what?
2. screening for what?
3. Does it correspond to prevalence of infected cows?
4. negative result means what?

Answer 12

1. herd infection level

what pathogens are present in the herd

1. hygience (lots of bacteria, especially certain types, indicate dirty cow and poor milking hygience)
2. contagious pathogens
3. NO!
4. NOTHING

Question 13

(46)

Question 14

(47)

Question 15

(48)

1. Can mastitis pathogens be diagnosed by clinical symptoms alone?

Answer 15

1. NEVER!

Question 16

(49)

(“Contagious PAthogens”)

1. Transmitted when what occurs?
2. pathogens?

Answer 16

1. when teats exposed to to bacteria that originiated in ifected udders (cow-to-cow, during milking, contaminated equipment or hands)
2. staph aureus, strep agalactiae, mycoplasma, other (prototheca?)

Question 17

(50)

(“Environmental Pathogens”)

1. transmitted when what occurs?
2. pathogens?

Answer 17

1 teats exposed to bacteria that originate in the environment (bedding, mud, manure - during milking form equip)

2. coliforms (E. Coli, Klebsiella, enterobacter)

environmental = streps

environmental staphs/CNS/staph spp

Question 18

(51)

(Contagious vs. Environmental)

(Infection characterisitcs)

1. contagious are usually what?
2. environmental usually what?

Answer 18

1. G+, mild to moderate clinicals may resolve w/o treatment - likely to revert to subclnical

(set up shop in mammary tissue and persist in balance with immune response)

2. G+ maybe clinical or sub (environmental streps sometimes behave more like contagious pathogens)

G- usually opportunistic, short duration, mild to severe clinicals

Question 19

(52)

(Contagious vs. Environmental)

1. However, some “environmental” pathogens have demostrated host adaptation - can be transferred via what?
2. In either catergory, some organsisms are difficult to treat whil e others are easy

Answer 19

1. via infected milk (E. Coli and Kleibsiella, Strep Uberis)

Question 20

(53)

(G- vs G+)

(G -)

1. illict what type of immune response?

2 rate of spontaneous cure?

(G +)

3. immune rsponse?
4. rate of spontaneous cure?

Answer 20

1. rapid, robust host immune response(why many coliform peracute)
2. high (up to 70%)

(lower for Kleibsiella though, and host adapted E Coli)

3. less robust
4. low rate (usually require intrammary antibiotic therapy with variable success)

Question 21

(54)

(Common Gram +)

(Staph Aureus)

1. catalase? coagulase?
2. G+ cocci

3 major contagious mastits pathogen, but variable prevalence here-to-herd (5-50%)

4. cure rates?

what two reasons?

5. chornic or acute?
6. Selecitve treatment based on cow factors, herd control by testing and segregating or culling

Answer 21

1. +, +

4 VERY LOW (< 30%)

not obligate (but forms micro-abcesses that IMM Abx can’t get to) AND some penicillin resistance

5. typically chronic with acute flare-ups, waxing and waning SCC

Question 22

(56)

(Common Gram Positives)

(Streptococcus Agalactiae)

1. catalase?
2. gram + cocci

3 use what to diff from environmental streps?

4. contagious, obligate udder pathogen
5. How easily cured by IMM Abx?
6. prevalence has declined greatly over the years due to what?
7. typically chornic, subclinical with 10-15% milk loss
8. herd approch to treatment and control is required (clinical case = tip of the iceberg)

Answer 22

1. neg
2. CAMP test
3. easily - no penicillin resistance. stays in lower gland and ducts with minimal interstitial tissue involvement
4. dry cow therapy

Question 23

(57)

(common Gram+)

(Coag- staphs)

1. Over 50 species, found on teat skin, nasal tissue,milkers hands, etc. (commensal, opportunistic)
2. what to distinguish from Staph Aureus?
3. Subclinical mas))s, low SCC (<200,000 cells/ml), clinical cases are typically mild
4. Minor pathogen – only 5-10% of clinicals
5. spontaneous cure rate?
6. control?

Answer 23

2. coag test (most non-aureus staphs are coag -)
3. high (economic benefit of treatment questionable, short duration therapy only for clinicals)
4. teat dipping and dry treatment

Question 24

(58)

(common Gram+)

(Environmental Streps)

1. catalse?
2. gram + cocci
3. CAMP - why is this useful?
4. MAjor pathogens - what % of clinicals?
5. CAuse high SCC, persistent infections, bac shed in milk
6. Sources?

7 Control - environmental management, hygiene to reduce teat exposure

8. Treatment?

Answer 24

1. neg
2. most are neg - diff from Strep ag

(S. Uberis is esculin positive, some are CAMP positive)

4. 20-25% (2/3 of sub become chronic)
5. shed in feces, bedding (straw), dry period
6. IMM Abx (longer duration tx may be indicated)

(failure to treat –> chronic)

(chronic subclinicals have poor tx success rates)

Question 25

(59) (common Gram+) (Environmental Streps) 1. "Non-ag Streps" typically lumped together - Strep Uberis, Strep dysgalactiae, etc... but what?

Answer 25

1. Strep uberis may be more significant, more likely to act like a contagious pathogen, and more difficult to treat (extended duration therapy indicated)

Question 26

(60) (Common Gram-negatives) (E Coli) 1. Most common coliform - it's everywhere 2. May be mild to sever depending on infective dose and host immune response 3. Treatment?

Answer 26

3. IMM not indicated in most cases (check SCC history), systemic and supportive therapy may be needed for severe cases

Question 27

(61) (Common Gram-negatives) (Klebsiella spp.) 1. how common? 2. severitiy? 3. Bacteria invade deeply into udder )ssue, destroy secretory cells, may become persistent and subclinical (Severely affected cows never return to normal milk production level) 4. Sources: feces, bedding (wood byproducts), dirty udders, infected milk 5. Control: ID subclinicals, segregate chronics, good milking, hygiene, consider bedding type, vaccinate 6. Treatment?

Answer 27

1. 2nd most common GN pathogen (K. oxytoca and K. pneumoniae) 2. 1/3 mild, 1/3 mod, 1/3 severe (GN endotoxin) 6. no labeled treatment, treat grade 1-2 based on previous history or treat all

Question 28

(62) (Common Gram-Negatives) 1. how control coliform mastitis? 2. What vaccine WORKS?

Answer 28

1. reduce exposure to pathogens in environment 2. J-5 core antigen vaccine (reduces clinical cases 50-80%) (should use 3 doses: 2 late gestation/pre-fresh, and 1 post-fresh)

Question 29

(63)

Answer 29

(64)

Question 30

(65) ("other pathogens") (Mycoplasma) 1. bacteria with no what? 2. what needed to isolate? 3. most common in milk samples? 4. contagious - transmitted how? 5. classic case? 6. treatment? 7. ID and segregate, cull ASAP (shed in very high numbers), close management of hospital pen/parlor to minimize transmission 8. Bulk tank and/or string samples to monitor

Answer 30

1 cell wall (so no target for ABx) 2. special media and icubation 3. M. Bovis (This and other spp. isolated from various body sites in both sick and well caUle) 4. air, blood, milk (purchased) 5 multiple quarters affected, decreased milk, cow not sick, normal (subclincal) to abnormal (clinical) milk, increased SCC 6 none, once infected always affected

Question 31

(66) ("Other" Pathogens) (Prototheca) 1. colorless, micro-algae (P. Zopfii) 2. ubiquitous in environment - esp where? 3. spread - contagious or environmental? 4. infections usually sub or clin? 5. treatment? 6. suspect for non-responsive cases 7. prevalence 4-40%, usually under 10 8. If found in BT culture, consider speciation?

Answer 31

2. wet areas 4. clincial (mild-mod) (chronic, high SCC, decreased milk) 5. non - ID, segregate, cull 8. there is no answer to this

Question 32

(67) (Yeast) 1. Rare - almost always due to what? 2. responsive to Abx?

Answer 32

1 iatrogenic due to dirty IMM infusion technique 2. no (some cure spontaneously) (evalulate SCC to determie when to cull)