Food Ani. Med- Cattle- Mastitis 1

wilsbach's version from 2016-03-31 23:50

intro and anatomy and junk

Question Answer
how many glands in bovine udder/ how are they separated?Composed of 4 glands. Separated into 2 halves.
How much do the glands communicate with each other in the bovine udder? ** Minimal to no communication b/t quarters and ducts are desperate
which quarters produce the most milk in the bovine udder?Rear quarters produce ~60% of milk.
Nanny and Ewe have how many glands? how is it separated?Each have two glands separated in half and drained individually by a single teat with a single streak canal.
which is bigger, goat or sheep udder?goat
how many glands in camelid udder/ how are they separated?4 quarters like the bovine, separated into 2 halves. fore and rear quarters of each half have separate ducts.
how many glands in sow udder, how are the separated?have 6-7 pairs (12-14 glands) arranged in 2 rows. Number on each side can be even or odd. Each gland is separate from the adj. gland. (little relationship between teat number and importance).
explain how the mammary gland makes milkalveolar (epithelial cells) make milk by removing nutrients from the blood and transforming them into milk and discharging the milk into the lumen.
what is an alveolus? what are a bunch of alveoli called? what surrounds the alveolus?alveolus is a single layer of alveolar cells. groups of several alveoli--> lobule. Myoepithelial cells surround each alveolus.
explain the milk ejection/milk letdown pathwaystim of mammary gland causes oxytocin release. Oxytocin stims myoepithelial cells to contract which ejects milk from the lumen and relaxes the teat sphincter. This is special bc it is a neuro-hormonal pathway-- there is no innervation of the secretory system! myoepithelial cells are not innervated!!
once milk is produced in the alveolus, what path does it take to the outside?alveolar cells produce the milk--> alveolar lumen--> mammary ducts (1* and 2*)--> Gland cistern--> teat cistern--> streak canal
why is it important to reduce stress if you want milk letdown to happen?catecholamines can inhibit oxytocin release--> inhibit milk letdown
how much blood flow does to udder during lactation/ how much per one gallon of milk (idk if #s are important but it's here to read)at peak lactation 280mls of blood pass through the udder each second. Requires400-500 gallons of blood per 1gal milk
What should you know about the milk vein?NEVER INJECT INTO IT DEAR LORD.
Making of milk: explain the interaction of hormones that lets this happen: what inhibits the formation of prolactin binding sites? (which allows prolactin to bind up and do its thing)progestin (I assume he means progesterone by this-- progestin is the synth Progesterone)
what two hormones help induce casein synthesis?prolactin+glucocorticoids
what hormone enhances prolactin production?estrogen
which hormone is responsible for directing more nutrients to the mammary gland?growth hormone.
which hormone is responsible for inc mammary cell numbers and activity?ACTH
which hormones influence synth, intensity, and duration of milk?TSH/ T3/ T4
what inc plasma Ca++ for milk production?PTH
when is milk production at a max?max 2-8wk past parturition. then gradually declines after that. (the rate of mammary cell loss exceeds rate of mammary cell division)
*does pregnancy affect milk production/lactation?preg has no effect on production till about 5 mo gestation. some species like cattle, horses, and camelids can have conception occur during lactation
A farmer comes up to you and he said he learned prolactin is what makes the cows make milk, and he wants you to inject them with prolactin to inc their milk. what will you tell him?exogenous prolactin has very little effect on milk production in lactating cows. Produces a slight inc in milk yield of goats during late lactation.
which hormone has a dose-dependant effect on the stim on milk yield of dairy cows and ewes?GROWTH HORMONE (not prolactin)
what is the 1* physical barrier of the udder to the outside world?streak canal
If you need to inject intramammary, how should you do it (all the way in or partial in, why)partial insertion to protect lining (not push bacteria into teat cistern)
what lines the bottom portion of the teat? how is the gland naturally protected during the dry season?bottom lined with keratin (bacteria gets stuck here) and there is a plug that forms during the dry period
what is flushing/flush milking? how might you get an even better flush milking?you milk the cow to help flush out the bacteria. admin of oxytocin inc milk letdown for even more flushing so more removal of bact
what is the main, non-pathogenic cellular defense of the udder?macrophages
how many macrophages in a healthy udder?<100,000 cells/ml
what does it mean if macrophages in milk? neutrophils?Normal for macrophages to be there, provided there aren't too many. neutrophils indicates infection. (possible to have over a million cells per ml in mastitic milk)
do the cells (macrophages/neuts) fxn better in blood or milk, why?function better in blood. There is no avail glucose for the cells to use in the udder, and caesin and fat coat the neutrophils
what are some non-cellular defenses of the udder?(1) Immunoglobulins (vxs can help with this) (2) lactoferrin (3) cytokines
what is lactoferrin, why is it in milk? what does it do?This is a non-cellular defense. Lactoferrin binds up iron (high in milk and up to 10 times higher in colostrum <--idk if he means the iron or the lactoferrin. Sick of this shit). This is particularly important with coliforms (bacteria which are rod shaped and G- usually in feces-- think E. coli). It's useful that it binds iron bc iron is essential for bact. growth.

Problems happen

Question Answer
explain the reasons why there is a higher risk of mastitis around parturitionimmune system depressed at calving, the teat sphincter is overwhelmed, they are often lying down in a dirty environment, and the gland is not being observed 2x daily in the milking parlor so probs can go unnoticed
non-infectious causes of teat end damage?trauma, chemical injury, frost bite.
explain how you can look at teat ends as indicator of teat healthcan score if there is a ring around the orifice and what condition it is in. (prolly dont have to score but to give you an idea, a pic)
what are 3 infectious dzs which affect the teats/leave lesions on the teats?(1) bovine papillomavirus. (2) herpes mammillitis (3) pseudocowpox
bovine papillomavirus: what does it look like? Does it cause problems? how is it spread? tx?wart-like lesions on teat and udder. Not a prob unless they are on teat ends. contagious- spread by machines and personnel. No tx, just px
Herpes mammillitis: what does it look like? Who tends to get this? Is there seasonality? tx?see vesicle and erosions, crusts and open sores might form as well. Common in first-calf heifers (stress I assume?) and it is more common in the fall/water (more stress?) and no tx, just px
pseudocowpox: caused by? looks like? how can you tell from regular pox? tx?caused by a PARAPOXvirus, it causes painful vesicles and circular raised areas that scab. (cowpox usually has ulcers but NOT scabs) no tx, just px
what is SUBCLINICAL mastitis?inflammation of the mammary gland without CSs of infxn. MOST COMMON FORM OF MASTITIS-- it will be a bacteria infection in the gland with WBCs in there, but no evidence of change macroscopically.
most common form of mastitis is?SUBCLINICAL
what is CHRONIC mastitis?persists in subclinical form for months/years with occasional chronic flare-ups
what is SUBACUTE mastitis?characterised by mild inflammation. Generally small flakes/clots in milk. no systemic signs of illness.
what is ACUTE mastitis?sudden onset of CSs. systemic signs are similar but less severe than peracute form.
what is PERACUTE mastitis?sudden onset of CSs, systemic illness often precedes the symptoms manifested in the milk and mammary gland
what are some things you can determine with US?is the quarter functional, is the teat obstructed, are there abscesses. (remember fluid is black)
what does the STRIP CUP/BLACK PLATE exam tell us? (how do you do it)(strip milk from each quarter into cup and look at it for color or consistency changes) it tells us if the cow has ******CLINICAL evidence of mastitis
things which you would see which could indicate clinical mastitis?flakes, gargot (clumps), watery, bloody
how common is subclinical mastitis?for every 1 cow with clinical, there is 10 with subclinical (clinical is tip of the iceburg)
What is the Somatic Cell Count (SCC) and what does it tell is?a somatic cell is any cell that isnt a germ cell-- for mastitis this usually means WBCs. The somatic cell count is used to tell us about ****SUBCLINICAL mastitis
SCC majority in good health? in mastitis?healthy= macrophages. mastitis= neutrophils
what are two indirect SCC methods, what are two direct?INDIRECT: CMT (cali mastitis test), WMT... DIRECT: direct microscopic, electronic (DHIA, detects subclinical, fossamatic machine)
how does the CMT and WMT differ?both are indirect tests. CMT is used stallside on an individual cow. WMT is used in bulk tank milk to estimate SCC of the entire herd
what is the fossamatic machine and how does it workit is a DIRECT SCC method and uses optical density to detect somatic cells.
explain how the CMT (california mastitis test) works (what are the agents, what happens, what does it meeeeean?)it is a cow side INdirect SCC method which uses Alkyl arylsulfonate and bromcresol purple to lyse the somatic cells and polymerise the DNA. A gel is formed by the DNA, more gel= more cells.
describe the proceure for the CMT(1) CLEAN TEATS (2) squirt small amt of milk into cup (apprx 0.5 teaspoon) and have each well have milk from a diff quarter. Make sure there is no xcontamination. Do not fill more than half full. (3) add equal amount (1:1 ratio) of reagent to each cup and swirl to mix. (4) read and record results within 30 sec
what is the score for the CMT based on/ what are the scores?based on how much gel is formed. can be a score of N, 1, 2, 3
what is the SCC max?currently 750,000 but soon 500,000 (EU is 400,000)
what are some things which can cause a false CMT which you should look out for?colostrum, inc WBCs, late lactation (at dry off time), less fluid milk (same #WBCs-- or inc), illness leading to abrupt dec in milk, first strippings of milk from teat (higher # of WBCs than rest of milk)
when do you culture your milk for possible pathogens (2 reasons yes 1 reason no)YES: if they are positive for clinical mastitis. If they are positive for subclinical mastitis. NO: any of the reasons there might be a false positive (colostrum, late lactation (or any other cause of dec in milk production), the first strippings, udder trauma, etc
(far or near) which side do you prepare first for a sterile milk culture collection? Which side do you collect from first?PREP far side first (so if you bump the near side you aren't contaminating them after you cleaned them) and COLLECT near side first.
explain procedure for a sterile milk culture collection(1) wash and dry udder if extremely dirty (2) pre-dip teats with 0.5% iodine (must remain on teats for 20-30sec prior to removal) (3) DRY THE TEATS-- THIS IS CRITICAL. Use SINGLE cloth/paper towel PER QUARTER/TEAT (4) clean teat orifice with alcohol on a cotton ball/ gauze pad. Single cotton ball per teat. When the cotton ball comes away clean, then the teat orifice is clean. Prepare far side first, then near side!! (5) Begin sampling near side- first strip the quarter you will be working with (use sterile gloves) by squirting out 3 streams of milk to cleanse teat canal. (6) remove cap from collection tube and hold upright in the same hand you will hold the tube with to prevent contamination (7) when collecting, hold tube as close to horizontal as possible to prevent contamination. (5mls is usually enough). (8) place tubes on ice if <48hrs till use, otherwise freeze. Ship samples early in the week!
what are the pros and cons of submitting your sterile milk samples as.... (1) individual quarters (2) a composite sample of the whole udder (3) bulk tank sample(1) best results and good for staph aureus and good for quarters that are positive on the CMT. However, this is expensive. (2) cheaper but more risk of enviro contamination (3) bulk tank samples let you test the whole herds udder health.
If you are looking at a bulk tank milk culture and it is positive for coliforms or streptococci, what do you think is going on?might indicate a problem with the premilking procedure instead of mastitis in the herd. This is bc these type of bact live on the ends of teats and can get into bulk tank during milking
parts of the milking machine (pic)
what should you do after removing the milking machine?dip teats