The importance of changing teat liners
Build Worn A With Up Milkstone Liner Picture: Of Teagasc
The milking machine is the most important machine on a dairy farm and its maintenance is vital for safe and efficient milking. As part of this maintenance, the teat liners need to be changed regularly, tells us more.
The teat liner is the only part of the milking machine that comes in contact with the cow, and their condition and design is critical for udder health, mastitis control and efficient milking.
The recommendation is to change liners after 2,000 milkings or six months, whichever comes first. Over time, worn liners reduce milking performance and decrease the speed and completeness of milking. Worn liners also increase teat end damage and the spread of mastitis-causing bacteria. Liners lose their elasticity as rubber deteriorates naturally over time. When liners become worn, they take longer to open and close on the cow’s teats while milking.
Milk liners are also exposed to hot water and detergents on a daily basis, and over time, this will also impact the effectiveness and efficiency of the liner.
Figure 1 illustrates a liner with a build-up of milkstone. This will cause the liner to become rough, causing small tears in the skin of the teat. This will also make cleaning and disinfecting these liners more difficult, allowing bacteria to build up in the liners, which may lead to higher total bacterial count (TBC), thermoduric counts, and somatic cell counts (SCC).
To calculate the number of days to get to 2,000 milkings:
- Firstly, multiply 2,000 by the number of milking units (A);
- Secondly, multiply the herd size by the number of milkings per day (B);
- Divide A and B = number of days.
For example, the following calculation applies to a herd of 120 cows milking twice a day in a 14-unit swing over parlour:
A: 2,000 multiplied by 14 = 28,000 B: 120 multiplied by 2 = 240 Divide A and B: 28,000 divided by 240 = 116 days Replacing liners When replacing liners, ensure that they are of good quality, compatible with the liner shells, and fit properly. The liner needs to have a soft, flexible mouthpiece that forms an airtight seal with the base of the teat next to the udder.
This will reduce liner slip and cluster falloff. It is also recommended that the inside of the liner shells be washed and cleaned before fitting the new liners. Ensure that the new liners are not twisted after fitting and that the liner markings are aligned. This is also a good time to inspect the other rubberware in the parlour.
They also have to withstand the effects of cleaning agents and high temperatures. Worn liners lose their shape and don’t massage the cow’s teats properly, leading to poor and inefficient milk out. Worn liners also harbour bacteria and will have a negative impact on SCC, TBC and Thermoduric counts.
