Dairy Medicine: General Mastitis

Question 1

mammogenesis: duct proliferation

Answer 1

estrogen

growth hormone

Question 2

mammogenesis: alveolar proliferation

Answer 2

progesterone

prolactin

Question 3

oxytocin and prolactin in milk generation

Answer 3

oxytocin: milk ejection
prolactin: milk production
both stimulated by suckling

Question 4

thyrotropin releasing hormone (TRH) & prolactin

Answer 4

(+) secretion: receptors on anterior pituitary lactotrophs

Question 5

vasoactive intestinal lpeptide (VIP) & prolactin

Answer 5

(+) secretion: inhibits hypothalamic dopamine synthesis

Question 6

estrogen & prolactin

Answer 6

(+) secretion: decreases lactotroph sensitivity to dopamine and increases the number of TRH receptors

Question 7

dopamine & prolactin

Answer 7

(-) secretion: blocks prolactin release form lactotrophs

Question 8

GABA & prolactin

Answer 8

(-) secretion: inhibits prolactin

Question 9

Bromocryptine

Answer 9

DA agonist. Supress prolactin secretion in goats

Question 10

epinephrine & oxytocin

Answer 10

(-) effects: epinephrine prevents oxytocin binding receptors on myoepithelial cells

Question 11

lactation duration & peak in cattle

Answer 11

305 days. peak at 6-8wks (40-60DIM)

Question 12

Posilac (synthetic peptide hormone)

Answer 12

increases milk production by 8-12lb/day

increased cellular rates of milk synthesis & maintenance of secretory cells

Question 13

milk composition

Answer 13

protein: 3.1-3.5%
fat: 3.5-5% (cow, goat) 7-10% (sheep, pigs)

Question 14

colostrum composition

Answer 14

85% IgG1

A, D, E vitamins

Question 15

infectious disease transmissible through colostrum

Answer 15

CAE
Mycoplasma
Johnes
Coxiella
Brucellosis
Salmonella

Question 16

soluble immune mammary defenses

Answer 16

immunoglobulins
lactoferrin
lysozyme
lactoperoxidase
complement

Question 17

somatic cell mammary defenses

Answer 17

uninfected population: macrophages
infected population: neutrophils
need >500,000 cells/mL for adequate protection

Question 18

bulk tank SCC target

Answer 18

<200.000 cells/mL

85% cows DHI score <5

Question 19

mastitis classification

Answer 19

subclinical / clinical: severity and clinical signs
contagious / enviromental: pathogen
acute/ chronic/ acute gangrenous: duration, severity

Question 20

milking pre-dip

Answer 20

environmental mastitis prevention

Question 21

milking post-dip

Answer 21

contagious mastitis prevention

Question 22

clinical signs of mastitis

Answer 22

hot/painful/swollen MG
enlarged supramammary LN
agalactia
abnormal secretion/ size/ texture
altered gait (pain)
hungry neonate
teat/ skin lesions