Motility Sensor

Rumen Motility Measurement System

eCow has developed a bespoke system to measure the pressure changes caused by the peristaltic movements of the rumen wall, otherwise known as motility. The device is designed for use in fistulated/cannulated research cattle where pressure sensors can easily be inserted into the rumen via the fistula without distress to the cow.

If you want to measure the effect of a diet formulation on the frequency and strength of rumen activity then this device is for you.

For any enquiries into this system please email

Why is motility important?

Rumen motility or contractions of the rumen are essential for proper digestive function in ruminants. Contractions not only serve to mix ingesta with digesta and inoculate ingesta with microbes, they also allow the expulsion of large quantities of gases produced as byproducts of bacterial fermentation.

The peristaltic movements of the rumen follow a regular contraction cycle approximately every 40 seconds, increasing in frequency during feeding and decreasing while resting. Multiple other factors can affect rumen motility including diet composition, environmental temperature, feed and water intake and also metabolic conditions such as hypocalcaemia. Suppressed motility (hypomotility) can result in ruminal impaction where the rumen becomes densely packed with indigestible roughage. This can have serious impacts on the cow’s health if it persists.

The type of diet a cow is given can significantly affect rumen motility. Grazing herds will spend a lot of time feeding and ruminating and therefore require strong and frequent contractions to allow efficient digestion. However, cows on diets high in concentrates, usually associated with low ruminal pH, often experience decreased motility, practically ceasing altogether if the pH drops too low.

As motility plays such a large part in the digestive efficacy of the rumen, it seems obvious that motility should be monitored when determining a cow’s ruminal health. As for what to do with the data collected, that’s up to you.

System Description

Motility Sensor 2The device measures rumen activity through two pressure sensors. These pressure sensors are fed into the cow’s rumen through a cannula stopper (Bar Diamond used as default) and positioned in two different locations within the rumen, typically in the upper ventral sac and reticulum.

They connect to an electronic logger outside the cow which will record readings every second and display real-time readings as well as battery power and time.


The system is battery operated to allow portability within the barn and total isolated protection of the cow from mains shocks or frequency effects. The sensor box is a portable unit with a rechargeable battery (12V) which should give at least 7 days of use while constantly logging.


  • Rechargeable 12V battery giving at least 7 days of constant logging
  • LCD monitor showing current pressure readings along with time and battery power
  • Four external connectors, two for the pressure sensors, one for charging and a USB connector for data downloads to a computer
  • Cannula stopper to hold pipes and reference pressure sensors securely in place, with metal and paper filters to prevent dust and water ingress
  • Pressure pipes made of braided transparent anti-kink PVC to allow regular inspection for rumen fluid advancing up the pipe
  • Two pressure sensing hoses, one 40 cm long to hang unaided in the ventral sac, the other 150 cm long to be weighed down in the reticulum
  • Pressure is logged every second
  • Dedicated software to extract data from the pressure logger


Data stored on the sensor box can be downloaded via a USB link whenever the system is not taking measurements. Software on Windows is used to download the data which is stored as .csv files with the two measurements displayed on the same timeline. Below is an example of the software used to monitor data flow.

Pressure Logger

Once the data has been downloaded it can simply be viewed in any spreadsheet software. Below is an example of the data you might expect to get, with both measurements plotted on the same graph. The orange line shows the activity in the ventral sac of the rumen and the blue line represents the reticulum.

Rumen Motility


Motility Sensor closeLogger

The motility sensor system nucleates from a central logging box, usually mounted to a wall or suspended above the cow. It does not require a mains electricity connection or an internet connection to function.

It has a liquid crystal display (LCD) which can monitor the current pressure readings along with time and battery voltage. The display automatically blanks after a short time to conserve battery power. The ‘Display’ button can be used to view the display when blank.

The ‘logging on’ and logging off’ buttons control the storing of data to memory. When logging is in progress a ‘*’ symbol is displayed in the bottom right hand corner and a time/date stamp is stored every time the logging status changes.

The logger has four external connectors, two connectors for the pressure sensors, a small charger connector for when the battery needs to be recharged and a USB connector for connection to a PC for data download. The USB and charging connectors need to be disconnected before accurate readings can be taken.

Cannula stopperCannula Stopper

Fitted with air tight cable glands, the cannula stopper holds the pipes and the reference pressure sensors securely in place. The delicate pressure sensor is located equidistant between filters and cannula stopper where a coaxial cable is fitted at right angles.


Braided transparent anti-kink PVC pressure pipes are used in the system. They are transparent so on regular inspection, one can see if rumen liquor is advancing up the pipe.


Metal filters, with replaceable paper filters inside them, are used to prevent rumen liquor from moving up the pipes while they are inside the rumen.