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Also known as: '''''Milking Machine
Also known as: '''''Milking Machine
# Effective parlour washing and cooling of the milk in order to prevent the build up of bacteria
# Effective parlour washing and cooling of the milk in order to prevent the build up of bacteria
==How the milk machine works==
==How the Milk Machine Works==
The milk machine works by having a collapsible '''liner''' within a solid '''pulsation chamber'''. The liner forms a seal at the top of the teat and connects with the '''short milk tube''' to deliver milk to the '''claw piece''' of the '''cluster'''. Via the '''short pulsation tube''', the pulsation chamber has an alternating vacuum/atmospheric air delivered which causes the milk liner to open and close beneath the level of the teat. When vacuum is present within the pulsation chamber, there is an equal pressure with that in the short milk tube, which has a constant vacuum supply to facilitate movement of milk away from the udder. The equal pressures means the liner is open and milk is drawn out. Conversely when atmospheric air is introduced into the pulsation chamber, the pressure differential causes the liner to collapse and the teat no longer to be exposed to the vacuum. This allows blood flow to return to the teat necessary to prevent teat damage and is called the '''massage phase'''. A constant vacuum applied to the teat, as in the early parlour designs, causes a vast amount of soft tissue trauma which would cause untold levels of mastitis.
The milk machine works by having a collapsible '''liner''' within a solid '''pulsation chamber'''. The liner forms a seal at the top of the teat and connects with the '''short milk tube''' to deliver milk to the '''claw piece''' of the '''cluster'''. Via the '''short pulsation tube''', the pulsation chamber has an alternating vacuum/atmospheric air delivered which causes the milk liner to open and close beneath the level of the teat. When vacuum is present within the pulsation chamber, there is an equal pressure with that in the short milk tube, which has a constant vacuum supply to facilitate movement of milk away from the udder. The equal pressures means the liner is open and milk is drawn out. Conversely when atmospheric air is introduced into the pulsation chamber, the pressure differential causes the liner to collapse and the teat no longer to be exposed to the vacuum. This allows blood flow to return to the teat necessary to prevent teat damage and is called the '''massage phase'''. A constant vacuum applied to the teat, as in the early parlour designs, causes a vast amount of soft tissue trauma which would cause untold levels of mastitis.
Most parlours are fitted with Automatic Cluster Removal apparatus. The milk machine detects when the milk flow rate falls to a pre-set “take-off” level (usually between 200 and 400 ml/minute). When this occurs, this triggers a cord to be retracted which is attached to the claw piece of the cluster. This pulls the cluster off the cow.
Most parlours are fitted with Automatic Cluster Removal apparatus. The milk machine detects when the milk flow rate falls to a pre-set “take-off” level (usually between 200 and 400 ml/minute). When this occurs, this triggers a cord to be retracted which is attached to the claw piece of the cluster. This pulls the cluster off the cow.
The advantages of the ACR is the prevention of over milking (which can cause teat damage and thus increased mastitis levels) and time efficiency for the parlour operator. However it must be remembered that the prevention of over milking is dependent on the take-off setting and therefore over milking can still be a problem in herds using ACRs. The disadvantages of using ACRs are that there may be more of a delay between milking and [[Post-Milking Teat Disinfection (PMTD)|post milking teat disinfection]], and occasionally premature cluster take-off will occur such as when bimodal milk flow is a problem.
The advantages of the ACR is the prevention of over milking (which can cause teat damage and thus increased mastitis levels) and time efficiency for the parlour operator. However it must be remembered that the prevention of over milking is dependent on the take-off setting and therefore over milking can still be a problem in herds using ACRs. The disadvantages of using ACRs are that there may be more of a delay between milking and [[Post-Milking Teat Disinfection|post milking teat disinfection]], and occasionally premature cluster take-off will occur such as when bimodal milk flow is a problem.
==Parlour washing==
==Parlour washing==
# Warm rinse
# Warm rinse
#* The first rinse should consist of warm water. If cold water is used, fatty residues tend to congeal onto the inner surface of the pipes which is more difficult to remove and will encourage bacterial replication. In addition the system will be cooled prior to the hot wash which will mean the hot water gets cooler quicker and less effectively clean the parlour. The aim of the warm rinse is to remove the bulk of the milk residues. The water is usually run to waste and should be continued until visibly clear.
#: The first rinse should consist of warm water. If cold water is used, fatty residues tend to congeal onto the inner surface of the pipes which is more difficult to remove and will encourage bacterial replication. In addition the system will be cooled prior to the hot wash which will mean the hot water gets cooler quicker and less effectively clean the parlour. The aim of the warm rinse is to remove the bulk of the milk residues. The water is usually run to waste and should be continued until visibly clear.
# Hot wash
# Hot wash
#* This consists of hot water (70-90°C) containing a detergent/ disinfectant that is circulated around the parlour. The temperature of the water should not fall below 40°C or fat may congeal and line the pipes. This final temperature can be measured at the end of the circulation wash as part of an investigation into a high Bactoscan level. As a subjective assessment it should not be possible to hold onto the milk transfer line during the circulation due to the high temperature conducted through the stainless steel pipes. The hot wash lasts approximately 5-8 minutes.
#: This consists of hot water (70-90°C) containing a detergent/ disinfectant that is circulated around the parlour. The temperature of the water should not fall below 40°C or fat may congeal and line the pipes. This final temperature can be measured at the end of the circulation wash as part of an investigation into a high Bactoscan level. As a subjective assessment it should not be possible to hold onto the milk transfer line during the circulation due to the high temperature conducted through the stainless steel pipes. The hot wash lasts approximately 5-8 minutes.
# Cold water rinse
# Cold water rinse
#* This last step is to remove any residual disinfectant from the hot wash.
#: This last step is to remove any residual disinfectant from the hot wash.
With circulation cleaning, it is important that the entire pipe is disinfected. In order to achieve this, the wash solution needs to be agitated. This is facilitated by the use of '''air injectors''' which inject regular bursts of air to cause the agitation. Air injectors help ensure the entire surface of the pipe is covered and make parlour washing more effective.
With circulation cleaning, it is important that the entire pipe is disinfected. In order to achieve this, the wash solution needs to be agitated. This is facilitated by the use of '''air injectors''' which inject regular bursts of air to cause the agitation. Air injectors help ensure the entire surface of the pipe is covered and make parlour washing more effective.
===Rotary===
===Rotary===
Rotary parlours are good for large herds due to the large throughput of cows possible. Cows may face the inside ('''external rotary''') or outside ('''internal rotary''') of the circle depending on the particular design. For a large rotary there should be at least three operators for an effective milking routine. One for udder preparation, the second for unit attachment and the third for [[Post-Milking Teat Disinfection (PMTD)|post milking teat disinfection]].
Rotary parlours are good for large herds due to the large throughput of cows possible. Cows may face the inside ('''external rotary''') or outside ('''internal rotary''') of the circle depending on the particular design. For a large rotary there should be at least three operators for an effective milking routine. One for udder preparation, the second for unit attachment and the third for [[Post-Milking Teat Disinfection|post milking teat disinfection]].
[[File:Rotary parlour.JPG|thumb|250px|center|External Rotary Parlour]]
[[File:Rotary parlour.JPG|thumb|250px|center|External Rotary Parlour]]
A static test is performed when cows are not present in the parlour. It involves measuring the vacuum level in various parts of the machine, calculating the vacuum reserve, ensuring adequate vacuum pump function and ensuring adequate pulsation (with a suitably long massage phase to ensure teat health).
A static test is performed when cows are not present in the parlour. It involves measuring the vacuum level in various parts of the machine, calculating the vacuum reserve, ensuring adequate vacuum pump function and ensuring adequate pulsation (with a suitably long massage phase to ensure teat health).
===Dynamic Tests===
Dynamic tests are performed when cows are being milked. The main aim is to measure vacuum fluctuations at the teat end which may not always be suggested as a problem by the results of the static test. Milk flow can also be measured which may reveal problems with bimodal milk flow, suggestive of problems with udder preparation and/or milk let down. It is during such tests that '''liner slip''' may be noticed.
Dynamic tests are performed when cows are being milked. The main aim is to measure vacuum fluctuations at the teat end which may not always be suggested as a problem by the results of the static test. Milk flow can also be measured which may reveal problems with bimodal milk flow, suggestive of problems with udder preparation and/or milk let down. It is during such tests that '''liner slip''' may be noticed.
File:Dynamic milk testing 2.JPG
File:Dynamic milk testing 2.JPG
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==References and Further Reading==
==References and Further Reading==
{{review}}
{{Nick Lyons written
|date = July 18, 2011}}
==Webinars==
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[[Category:Dairy Cow Management]]