Milking Procedures. Treat every quarter of every cow at dry-off with an approved dry cow therapy.

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1 Milking Procedures Michael M. Schutz, J. Francis Kearney, and Simon J. Kenyon Purdue University Departments of Animal Sciences and Veterinary Clinical Sciences Practice makes perfect! There are many reasons to establish and stick with a sound milking routine that works well for a particular dairy. Obviously, the most important reason is to get as much high-quality milk as possible per cow. But there are other very important reasons as well. Milking procedures play a large role in reducing or eliminating mastitis and lowering somatic cell counts, which are important in terms of animal health and milk quality premiums. Another reason to establish a routine milking procedure is that it should be quick enough to allow smooth flow of cows through the parlor, while giving each cow enough stimulation and time to achieve an effective milk letdown response. Speed of the milking routine can be measured either by number of cows milked per hour or by the amount of milk harvested per employee per hour. An often overlooked goal of a good milking routine is that it ought to be simple enough that every milker can use exactly the same routine for every healthy cow every time. From the consumer s point of view, the most important reason to establish a good milking routine is to ensure milk quality. After all, milk has a reputation as a fresh and wholesome product and that image must be maintained. All of these goals must be balanced when deciding on an appropriate milking routine for the herd. The routine that works best for one herd may not work as well for another, but certain considerations are common to all successful milking procedures. All successful milking routines allow milking inflations to be attached to clean, dry teats. Treat every quarter of every cow at dry-off with an approved dry cow therapy. These recommendations are as true today as when they were first written many years ago. Remember, the most important part of any milking routine is to put the inflations on clean, dry teats. Doing this every time you milk every cow is vital from the standpoint of milk production, mastitis management, milk quality and the rate at which cows are milked. It may or may not seem surprising that a successful milking routine begins where the cows spend most of their time. Maintenance of the environment is an often overlooked but important part of the milking routine! Housing areas and cow traffic areas should be kept as clean and dry as possible. This is important in reducing the amount of dirt that will need to be removed from teats and reducing the number of mastitis-causing bacteria on the teats. Freestalls must be dry, and bedding material must be replaced frequently. Stalls should be groomed at each milking. Avoid bedding with non-dried wood shavings, because green shavings may encourage growth of certain kinds of mastitis causing bacteria, such as klebsiella species. Sand bedding does not support bacterial growth, but it may not be compatible with the existing manure handling equipment. The following points have long been made when recommending milking procedures: Provide sanitary housing for cows. Ensure gentle cow movement and comfort. Use proper milking procedures. Ensure proper function, adjustment, and sanitation of milking equipment. Dip teats after milking. Figure 1. Cow housing. Stall comfort is vital to encourage cows to lay in dry, bedded stalls rather than in scrape alleys

2 and traffic areas. Use of mattresses in stalls reduces the amount of additional bedding, but bedding is still required to prevent friction injuries. Huge amounts of fresh bedding must be frequently added in tromp sheds to maintain a dry surface over the manure pack. Fresh bedding must be continually maintained in tie stalls. The milking routine can be simplified by proper maintenance of correctly sized stalls, which keep cows clean and comfortable. Even under grazing conditions where cows are on dry pasture, one must assure that cows do not have access to muddy ponds, small shaded areas with bare ground, or mucky cow lanes where they may come into contact with pathogens that cause coliform or other environmental mastitis. Remember that dry cows and heifers also need clean, dry facilities to avoid mastitis problems. Anything that startles, distracts, frightens, or otherwise stresses a cow will interfere with the milk letdown response, reduce milk production, and slow cow movement through a parlor. The following steps are necessary to ensure cow comfort and to enhance the milk letdown response. Avoid prolonged waits in the holding pen. Cows trapped in the holding pen generally do not have access to feed and water. If this wait is unduly long, dry matter intake and water consumption may be reduced, and hence they will produce less milk. Strive to keep cows in the holding pen no more than 2 hours total per day. Less is better. Assure smooth cow flow. Remove obstructions between cows and the parlor. Even visual obstructions can make cows balk at entering the parlor. Avoid sharp turns and steps. Be sure exits are set up such that cows can maneuver around turns. Ramps with gradual slopes and grooved concrete are much easier for cows to walk on than are steps. Keep the milking parlor free of startling noises. Cows probably won t mind radio music playing in the milking parlor, as long as it is not too loud and not distracting to the milkers. We don t know if cows prefer Rock, Country, Classical, or Polka music, which means that any music that keeps milkers happy and productive probably is good for the cows too. 2 Feeding in parlor? Feeding may encourage cows to enter the parlor quickly, but may interfere with cows orderly exit from the parlor. If cows are fed in the parlor, great care must be taken to keep the parlor clean of feed residues, insects, and rodents. Administer injections outside the parlor. Injections, flaming udders to remove hair, trimming switches, and other procedures which cows may find painful or startling should be done outside of the milking parlor. Figure 2. A milking cow Cows are creatures of habit and that makes it quite important that a single milking routine is established for the dairy. Every milker should be able to follow the routine and apply the same routine to every cow at every milking. It is best if there is a written set of standard operating procedures for milking. That way every milker knows exactly what is expected. The written procedures also help when training new milkers. An example standard milking procedure is included at the end of this publication. If every employee follows the same routine, it is less likely that any accidents, such as milking an antibiotic treated cow into the bulk tank will happen. Also, the milking procedure itself will provide a correctly timed stimulus to trigger oxytocin release and milk letdown. The goals of a good cow preparation procedure are to: Limit use of water. Allow the milker to target the teat with an approved pre-milking dip, sanitizer, or wash.

3 Sanitize/kill bacteria, but not contaminate milk. Provide adequate time for teat sanitation. Allow sufficient time for milk letdown stimulation. Remove organic matter from the teat surface. Eliminate variation in milking routines. Not slow down milking. The less water that is sprayed onto the udder, the less the chance that micro-organisms that reside on the teat and udder skin surface will be washed down and congregate at the teat end. There they could enter the udder through the teat end during milking and cause a mastitis infection. Using a teat wash with sanitizer or a pre-dip is encouraged, but only works well if given sufficient contact time. Some dairies have success simply by wiping teats with a dry towel to remove obvious dirt. In most cases this is not a recommended practice because of increased risk of getting sediment or dirt in the milk and not killing bacteria on the skin surface. Some opportunistic bacteria reside on the skin surface and their populations are dramatically reduced by sanitizers and pre-dips. The National Mastitis Council has recommended the following 8 point milking procedure. Most dairies are using all or nearly all of these components in their milking procedures. required. However great care should be used to sanitize hands after prepping a sick, mastitic, or high somatic cell count cow. Before milking. Assure milking equipment function as part of the normal milking routine. Prior to each milking, check the vacuum controller, milking vacuum, milk hoses and liners for holes or tears. Also check pulsators and air admission holes in the milking claw. Properly functioning milking equipment is essential to all of the goals discussed previously. Predipping It is generally accepted that predipping may reduce environmental mastitis by 50% in some herds. Its effective use can present some risk. The risk is one that can be managed through common sense approaches. Use caution to wipe teats and prevent contamination of milk. Also, use only a dip which is listed with FDA, has known ingredients, and has predipping instructions. When predipping teats, be sure to : 1. Pre-clean teats of visible dirt. Dirt or manure can prevent the pre-dip from penetrating to the skin surface to effectively kill bacteria. 2. Apply Predip. Nonreturn dip cups, spray bottles, and spray wands can each be used successfully if care is taken to assure complete coverage. 3. Forestrip. 4. Allow at least 30 seconds of contact time. 1. Provide a clean, stress free environment. 2. Check foremilk and udder for mastitis. 3. Wash teats with udder wash/sanitizer. 4. Dry teats with individual towel per cow. 5. Attach milking unit within 1 minute. 6. Adjust unit for proper alignment. 7. Shut off vacuum before removing unit. 8. Dip teats immediately after unit removal with an approved and effective dip. Hands should be washed frequently during milking. Milkers must wear synthetic gloves. Gloves protect milkers hands and provide a smooth surface that is easily sanitized. Milkers should be encouraged to wash their hands after prepping each cow. In a real milking routine, this may not be practical because of the time Figure 2. Predipping. Forestripping. Forestripping is a good practice and may dramatically improve mastitis management and lower somatic cell counts when practiced routinely. Stripping several squirts of foremilk from each teat accomplishes five 3

4 things. Forestripping 1)allows one to feel any abnormalities in the teat or quarter, 2)allows one to see any abnormalities or flaking of the milk, 3)allows the predip or sanitizer to be worked onto the skin surface, 4)provides the most forceful stimulation signal for the milk let-down response, and 5)removes the milk with highest SCC or bacteria levels. Drying. It is vital that individual towels are used for each cow. Either paper towels or laundered and dried cloth towels can be good options, but a separate, clean one must be used for each cow. If cloth towels are laundered and reused it is recommended to accomplish at least two of the following: 1) Wash with bleach, 2) Wash in hot water, or 3) Use a heated drying cycle. If towels are not dried, they must be used quickly after washing to prevent bacterial growth on the towel. Figure 3. Drying with individual towels. Attaching the milking unit. Optimum time from initial contact with the cow to attachment of the milking unit is 50 to 80 seconds to stimulate the milk letdown response. This timing ensures that the milker will not be attached too long prior to peak milk let-down, but will not miss peak milk let-down. Overmilking can occur either at the beginning or end of milking; and either can result in callused and damaged teat ends. Often this amount of time can be accomplished in a parallel or herringbone parlor by prepping 3 or 4 cows and then returning to wipe and attach the milking units to those cows in the same order. This is then repeated for the next 3 or 4 cows and so on. When there is more than one milker, the proper timing can be accomplished by territorial milking where each milker attends to cows in a specific part of the parlor and preps and milks them as above. The timing can also be maintained by having the first person pre-dip and forestrip all of the cows on one side of the parlor, with a second person following to wipe and attach each cow about 60 seconds after the first. Timing can be easily maintained with a rotary parlor by having a different person performing each task at their own station. The speed at which the cows move dictates where each task is performed so that the proper timing is maintained. Again, milk teats that are clean, dry, & free of residue! Researchers at the University of Minnesota devised the Minnesota Once-Under or Minnesota One-Step milking preparation procedure to meet the goals listed above, and to simplify the process. The Minnesota Once- Under procedure is designed to provide adequate contact time for sanitizing teats, adequate stimulation time to enhance milk let down, but a method quick enough to allow the entire preparation to be completed at one time. According to their studies, the average milker spends about 10 seconds per cow, which is not adequate stimulation or contact time. The Minnesota Once Under Technique includes: 1. Dip each teat with approved teat dip covering at least 3/4 of the entire teat. 2. Clean teats with 3-4 vertical hand motions, then use the thumb and first finger in 2-3 horizontal motions across the teat end to remove debris. Strip 2-3 squirts from each teat end to remove foremilk and check for clinical mastitis (about 5-7 seconds per teat). 3. Walk away and allow > 30 seconds of contact time (enough time to rinse hands and grab a towel), then dry teats with a singleuse towel and continue with proper milking procedures. Wipe teats in the same order they were prepped. This gives a total of about seconds from initial stimulation to attachment of the unit. A variation for a single milker may be to prep and attach units to 2 cows at a time (prep A, prep B, 4

5 wipe and attach A, wipe and attach B). If 2 people are milking, the first can prep, while the second follows 3 cows behind, wipes, and attaches. During milking. Teat end impacts occur when vacuum fluctuations, often caused by slipping or squawking liners, project rapidly moving droplets of milk back toward the teat end. Some of these tiny droplets of milk actually enter the teat through the relaxed sphincter and streak canal, and can lead to a mastitic infection if the droplet contains pathogenic (infection causing) bacteria. Squawking liners must be tended to immediately! Liner slips are a parlor emergency. While this discussion of milking procedures has stressed the importance of establishing a routine that is applied to every cow every time; there is an important exception. When you hear a slipping or squawking liner you should drop whatever you are doing (within reason) and tend to it immediately! Maintaining milking systems and properly adjusting the milking unit will prevent most liner slips. As soon as milking letdown stops. Avoid overmilking, which causes stress and injury to teat ends. Shut off the vacuum before removing the milker. This is important for the cow being milked, but resulting air intake can lead to vacuum fluctuations that can cause teat end impacts for other cows too. Post-dipping. This is absolutely necessary after each milking. Use only products that are listed with FDA and that are proven effective. Manufacturers should provide information about the effectiveness of the product. The measures of the effectiveness have been standardized by the National Mastitis Council, and should be used by manufacturers in testing their product. Figure 4. Post-dipping. Effective ingredients in teat dips include: 1. Chlorhexidine -.5% 2. Iodophor -.5 to 1% available iodine 3. Hypochlorite - 4% 4. others When (not if) dipping teats after milking: 1. Cover at least 3/4 of the teat or all of the teat that has been inside the inflation. 2. Use an effective applicator to apply dip to the teats. Non-return dip cups probably work the best, although they may be somewhat messy. For convenience, it may be tempting to use a sprayer to apply teat dip. This is usually not a good idea. In fact, unless you turn the bottle backwards, reach beyond the teat and spray back at your face, it is unlikely that you will apply any dip to the far side of the teat. Cone shaped spray wands may allow one to reach all surfaces of the teat, but are expensive and will waste more dip. Ring type sprayers will apply dip to the entire target area of the teat, but they are expensive, pores can clog easily, and they are rather susceptible to cow kicks. Two other points about milking practices should be made, although they may not pertain to the day to day milking routine. Sick cows, treated cows, cows with clinical mastitis, or cows with elevated somatic cell counts should be milked last. If the cows can not be segregated, keep a separate milking unit to be used only for the sick or treated cows. Milking these cows last will help prevent the spread of disease to healthy cows, and, in the case of treated cows, will be an extra reminder to withhold the milk from the 5

6 bulk tank and avoid the penalty for antibiotic residue. At the last milking before dry-off, treating every quarter of every cow with an approved dry cow treatment is a wise practice. Dry treatment can help to clear up any lingering mastitis infections from the previous lactation and prevent new infections, which are very prevalent during the early dry period. The best milking practices to promote milk quality can be summarized as: 1) Provide sanitary housing for cows. 2) Ensure gentle cow movement and comfort. 3) Use proper milking procedures including milking clean and dry teats. 4) Ensure proper function and adjustment of milking equipment. 5) Dip teats after milking. 6) Infuse every quarter of every cow with an approved antibiotic at dry-off. 6