Mammary System

Objectives Identify the parts of the udder. Describe the function of the cow’s udder. Describe milk let-down and the processes of that.

Parts of the udder Made up of 4 glands called quarters Each quarter has a teat that provides an outlet for milk

Parts of an udder

Can you see the quarters?

What about here?

So..what makes the milk? Udders contain alveoli that manufacture milk Blood carries all the raw materials to the alveoli Each alveoli contains cavities for milk

Parts of the Udder Teats Contain a small opening called “streak canal” A narrow streak canal and strong muscle=cow that is harder to milk A wide streak canal and weak muscle=easy to milk but can leak when udder is full

Milking – by hand, machine, or calf

Milking – by hand, machine, or calf Squeeze the teat from top to bottom Machine works in the same way with a vacuum action

What do udders do? Manufacture milk Store milk until cow is milked or calf nurses

Milk Let-Down Process when cow responds to a conditioned reflex to sensory stimuli Stimuli: an event that promotes a response either consciously or unconsciously

Milk Let-Down Stimuli can be a number of things and often in combination: Washing and/or touching of the udder Sight of a calf Sound of a milk machine This triggers a response in the cow to release oxytocin

What are some of our responses to stimuli? Getting your books out at the beginning of class when the bell rings Shutting off your alarm in the morning Hunger at the smell of food Fear at the sight of heights, spiders, snakes, etc.

Oxytocin and Milk Let-Down With stimuli, the pituitary gland releases the hormone oxytocin What are human hormones? Do humans have oxytocin? This is carried to the udders through the blood

Oxytocin – what it does Causes muscle fibers to squeeze milk from the alveoli into the gland cistern Milk Let-Down must occur before milk can successfully be removed from the udder Oxytocin effect lasts about 5-7 minutes

The Big Picture Udders produce milk all the time and pressure builds in the udders with milk storage As pressure increases=production decreases so regular milking is important About 80% of the milk is taken at each milking Cows will dry up sooner if not enough milk is taken

Things to look for with the mammary system Mastitis Inflammation of the mammary gland caused by bacteria Disease is followed by an infection Usually only affects one quarter Symptoms: Udders will be Swollen Hot to the touch Red Abnormal Milk (lumpy, contains blood)

Swollen Udders

Redness and swollen

Treating Mastitis Identify the bacteria that caused it Maintain Milking Equipment Use approved mastitis medications Treat as quickly as possible

Review What are the parts of the udder? What do udders do? What is oxytocin? How much milk is taken after each milking?