Continued Following initial presentation or Video LACTATION Continued Following initial presentation or Video

REVIEW External Anatomy Attachments Teats Differences between quarters (rear=60%)

Udder size Does it matter?

Abnormalities Accessory teats Common Best removed (make sure it’s the right one) If present, may interfere or cause infection

Internal Anatomy Streak Canal Teat cistern Gland cistern Duct system Secretory cells (alveoli) Blood and nerve supply Myoepithelial cells

Milk Letdown – Neurohormonal Nerve side = Hormone side =

Interruption of Milk Letdown Epinephrine interferes with oxytocin effect Myoepithelial cells relax Factors Loud noise Dogs Sores Strangers teat cups irregular feed

Machine milking Vacuum level 10-16 mm Hg Pulsator alternates outer chamber to inner (vacuum to normal air pressure) 48-52 pulses / min Prevents blood congestion in teat

Udder development Before puberty – somatotropin Estrogen Causes duct growth (and heat [estrus]) Secreted by ovaries Stimulates growth & branching of ducts Ducts increase with each heat period Increases blood supply to udder

Progesterone Secreted by Corpus Luteum Duct AND alveolar growth

Prolactin Enlargement of ducts & alveoli Stimulates secretion (precolostrum) From anterior pituitary Lactation curve is dependent on prolactin

Good Milking Technique By National Mastitis Council Wash udder with warm sanitizing sol’n Dry with single service paper towel Remove 2 – 3 streams of milk from each quarter and examine for abnormalities Attach teat cups ~ 1 min after starting udder prep – or when teats full of milk

Adjust teat cups during miling as necessary to insure quarters milk out properly Start machine stripping when milk flow slows (3 – 4 min). Do NOT OVERMILK Dip teats in a teat dip after teat cups removed Treat all clinical cases of Mastitis Treat cows at drying off Conduct cowside screening test (CMT – Calif. Mastitis Test) at monthly intervals. Record results.

Have the entire milking machine system analyzed twice a year by a qualified milking machine service man.