EnglishWhat is a rumen bolus and how does it work?
A rumen bolus is a small sensor that a veterinarian gives to a cow by mouth. It stays in the rumen and continuously measures the cow's body temperature, activity and drinking behaviour. Readings are sent to a mobile app, so fever, heat and upcoming calving are flagged hours before they can be seen.
What is the rumen?
A cow's stomach has four compartments: the rumen, reticulum, omasum and abomasum. The rumen is the largest of these and is where feed is fermented. Because it is one of the places that most consistently reflects the cow's core body temperature, the rumen is an ideal measuring point for health monitoring.
How does a rumen bolus work?
- Administration: The bolus is given orally by a veterinarian using a special balling gun. Its weight takes it down into the reticulo-rumen, where it stays.
- Measurement: The bolus measures the cow's body temperature and activity at regular intervals.
- Transmission: Readings are sent to the cloud via the receiver in the barn.
- Analysis: The system learns each cow's own normal and detects deviations from it.
- Alert: When signs of fever, heat or calving appear, the farm owner, herdsman and veterinarian are notified instantly.
What does a rumen bolus alert you to?
- Fever: Infections and diseases often show first as a rise in body temperature. Catching fever early means faster treatment and less milk loss.
- Heat (oestrus): The increase in activity during heat is picked up, so the right insemination time is not missed.
- Upcoming calving: A drop in body temperature in the hours before calving signals that calving is near.
- Inactivity and changes in drinking: These can be early signs of lameness, digestive problems or heat stress.
What is a cow's normal body temperature?
A healthy cow's body temperature is usually in the range of approximately 38–39.5 °C. However, each cow's normal is slightly different, so assessing her against her own history gives more accurate results than a fixed threshold. When a cow drinks, rumen temperature drops temporarily; a good system distinguishes this drop from illness.
Does a rumen bolus harm the animal?
The rumen bolus is made from animal-safe materials and is administered by a veterinarian in a single step. It stays in the rumen and does not affect the cow's eating, rumination or milk yield. It needs no maintenance, charging or battery changes; the Edell Biosense bolus lasts 3 years.
Rumen bolus vs. ear tag and neck collar
| — | Rumen bolus | Neck collar | Leg sensor (pedometer) |
|---|---|---|---|
| Position | Inside the body (rumen) | On the neck | On the leg |
| Core body temperature | Measures | Cannot measure | Cannot measure |
| Activity / heat | Measures | Measures | Measures |
| Risk of loss or breakage | Very low | Yes | Yes |
| Maintenance | None | Adjustment and checks | Adjustment and checks |
The ear tag, on the other hand, is the cow's identity. In Edell Biosense, each bolus is paired with the cow's ear tag number, and every cow appears in the app under her own ear tag number.
Who is it suitable for?
It suits dairy and beef cattle farms of every size, cooperatives and veterinarians. It brings the greatest benefit on farms where night checks are difficult, staff numbers are limited and the herd is growing.
Frequently asked questions
What is a rumen bolus?
A rumen bolus is a small sensor that a veterinarian gives to a cow by mouth. It stays in the reticulo-rumen and continuously monitors the cow's body temperature, activity and drinking behaviour. The Edell Biosense bolus sends this data to the mobile app, so fever, heat and upcoming calving are flagged hours in advance.
Does the bolus harm the animal?
No. The bolus is given orally by a veterinarian and stays in the cow's rumen. It is animal-safe and does not affect the cow's daily life or milk yield.
How long does the bolus last?
The bolus lasts 3 years. The app shows the status of every bolus at all times.
When do the alerts start?
Monitoring starts straight after installation. In the first days the system learns each cow's own normal, and alerts become increasingly accurate.
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