Editor’s note: This article was written by Jennifer Heguy, University of California Cooperative Extension Stanislaus & San Joaquin Counties and Ed DePeters, University of California Davis and first appeared in the California Dairy Newsletter. This article is also available in Spanish.
A key factor for a good milking is the hormone oxytocin. Oxytocin is responsible for milk let-down, and without oxytocin, cows will not be milked out completely or rapidly. Oxytocin is released into the blood in response to various stimuli, and causes contraction of the udder’s muscle cells. Milk is available for removal from the udder because of these contractions. The process of oxytocin release can start with stimulation of the teats, specifically the teat ends, as this is where most nerve receptors are located. The sound of the vacuum pump in the parlor, or even the act of walking to the parlor, can also be stimuli for oxytocin release. Milking procedures either contribute to or depend upon this release of oxytocin.
Another important component of milking procedure basics is that it is a good practice for milkers to wear disposable gloves. Gloves are easier to sanitize than hands, helping to prevent the spread of bacteria from cow to cow as well as helping protect the milker’s hands.
Step 1: Start by providing animals with a clean, low stress environment. An animal that is fearful or stressed releases adrenaline. Adrenaline inhibits oxytocin release, and reduces the action of oxytocin in the mammary gland. Cows are creatures of habit and should be brought to the parlor in the same fashion at every milking. Refrain from yelling or sudden movements, and watch for overuse of crowd gates. Dogs in the parlor or alleyways may also illicit a fear response in cows. The next few steps address preparing the udder for milking. Variations in the milking process do not matter as long as the end results are clean, dry teats and the release of oxytocin.
Step 2: Stripping teats serves as an important stimulation for oxytocin release and also allows for clinical mastitis detection. Some cows will have mastitis and never show symptoms, but abnormal milk is a sign of infection. It’s important to remember that we want to strip the milk onto the floor, and never into paper towels or hands. If the milk is contaminated with bacteria, bacteria can easily spread from hands to other teats or animals.
Step 3: When applying sanitizing solution (pre-dip), the objectives are good coverage and proper contact time. Contact times vary with product, so refer to the label. Ensure the teat ends are properly sanitized.