When to replace liners?And why this is important
Teat Liners: simple upkeep, stronger milk results
Introduction
Teat liners (also called milking liners or inflations) are the only parts of the milking machine that touch the cow. Their fit, feel and age directly steer milk flow, udder health and overall parlour efficiency. Fresh, correctly sized liners empty every quarter quickly and gently; worn or poorly matched liners slow milk-out, raise teat-end callousing (hyperkeratosis) and open the door to mastitis.
In this article you read about when to replace your liners and why doing this on time is important.
Why fresh liners matter?
Why Timely Liner Replacement Matters
Teat liners are the frontline of every milking system; they touch the cow an average of 50–65 times per minute, per teat. Over time, rubber inflations stiffen, lose their natural grip, and develop micro-cracks that shelter bacteria. These changes cause liner slip, incomplete milk-out, and rising somatic cell counts—early red flags for mastitis. Sticking to a strict replacement schedule—or better yet, upgrading to durable high advanced silicone liners—restores a better teat condition, speeds milk flow, and maintains udder health with every milking.
Why to choose silicone over rubber?
Rubber inflations that stay in service too long become rigid and develop micro-fractures. Those tiny crevices trap pathogens, raise bulk-tank cell counts, and turn a minor irritant into a full-blown mastitis problem. Slipping cups also slow milk-out, forcing cows to stand longer and stressing teat tissue.
Switching to high quality and advanced silicone liners – like AktivPULS, tackles three core risks at once:
- Complete milk-out – supple silicone grips evenly and doesn’t crawl, so every quarter empties fully at each milking.
- Healthy teat ends – a soft, elastic mouthpiece minimises vacuum bruising and prevents the thick callus we call hyperkeratosis.
- Cleaner milk path – non-porous silicone rinses spotless, making sure bacteria have no place to attach during rinsing.
When to change liners?
When to Replace Teat Liners—and How to Stay Ahead of Problems
Ideal service life
- Standard rubber liners: 2 000–2 500 milkings or 6 months—whichever comes first.
- AktivPULS silicone liners : up to 10 000 milkings or 12 months.
Early warning signs
- Hard or sticky feel when you squeeze the liner mouthpiece.
- Visible cracks or milkstone that won’t scrub off.
- Cup slip, crawl, or slow milk-out during milking.
- Rising somatic cell count (SCC) or more cases of mastitis / hyperkeratosis.
Quick formula to set a change date
- Milkings per cluster per day(Number of cows)×(milkings per cow per day)÷(number of clusters)\text{(Number of cows)} \times \text{(milkings per cow per day)} \div \text{(number of clusters)}
- Days until replacementMaximum milkings for your liner÷milkings per cluster per day\text{Maximum milkings for your liner} \div \text{milkings per cluster per day}
Example
120 cows × 2 milkings ÷ 10 clusters = 24 milkings/cluster/day
Rubber liner: 2 500 ÷ 24 ≈ 104 days → schedule change every 3½ months.
Replacing liners on time—and choosing durable silicone inflations where possible—keeps milk flowing fast, protects teat ends, and lowers your mastitis bill.
Picking the best liner for your parlour or robot
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Fit first:
- The liner’s length, wall thickness, and mouthpiece diameter must match the shell and the average teat size in your herd. An oversized head won’t seal tightly, leading to cup slip and higher kick-off rates.
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Pick the right material:
- Silicone liners – stay supple for up to 10 000 milkings, treat teat ends gently, and rinse clean in seconds.
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Rubber liners – cheaper at purchase, but harden quickly and need two-to-four times more frequent replacement.
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Vented vs. non-vented:
- A built-in air vent draws milk away from the teat tip and prevents back-flush, leaving teats dry and lowering mastitis risk.
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Geometry matters:
- Looks can deceive: AktivPULS liners include a patented 45° closing angle that snaps shut as soon as milk exits the barrel, stabilising vacuum and protecting teat tissue.
- Choose the right head size: Match mouthpiece diameter to the average front- and rear-teat widths in your herd to keep vacuum balance steady and stop liner slip or crawl.
Keeping your system optimum
Liner slip & incomplete milk-out
Incorrect dimensions or liners without grip rings fail to seal, causing cups to crawl or drop and leaving milk behind.
High replacement frequency
Rubber inflations harden fast; swapping them every few weeks stalls the robot or parlour and takes up labour hours, while silicone liners stay flexible and have a longer life span.
Vacuum & pulsation drift
Ageing hoses, claws, and regulators pull settings off target, stressing teat tissue and slowing flow unless recalibrated.
Teat-end damage
Stiff or oversized liners bruise the teat-end, leading to hyperkeratosis and poorer udder health; schedule an annual teat-end condition score to catch problems early.
Common challenges:
- Liner slip & incomplete milk-out
- High replacement frequency
- Vacuum & pulsation drift
- Teat-end damage
"Tobias van Korven – Director"
Milking with ™AktivPULS has offered many dairy farmers a solution to overcome hyperkeratosis and achieve greater efficiency with both robotic and traditional milking. I am happy to be able to make such a difference in this particular industry. If you have experience with the ™AktivPULS way of natural milking, please let us know via our contact button! Your response may be added to our list of testimonials!
"Henry Molenaar"
These nipple liners brought me two things. One is an improvement in those teat ends. With dry-off it's searching for the teat holes. But also importantly, a very big piece of improvement in milk speed. I found changing liner quite exciting. After all, I went from rubber to silicone. But the somatic cell count results, they went down from 170 to 63. I am very happy with that. What I am also very pleased with is the interval of changing. With rubber, I was at 2,500. Now it is every 10,000. That still saves a lot of work. After 2.5 years of milking with AktivPULS, I will definitely not go back to another type of liner.
De Bladelse Hoef
"80% less hyperkeratosis and 20% less mastitis"
In August, we started milking with AktivPuls. During the trial period, we only changed the liners. Before the trial, practically 80% of our cows showed signs of teat-end hyperkeratosis, 20% of which was of the 4th degree. Currently, there are no cases of hyperkeratosis in the entire herd. Previously, we had 40 to 50 cows showing signs of clinical mastitis, but now we have a maximum of 10. Subclinical mastitis has decreased from 20-25% to 3-4%.
SPK Zhdanovskiy