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Early-Warning Device Looks For A Market

In a large feedlot finding sick animals and removing them from the pen can be a full-time job. Illness cannot be identified until visual symptoms occur, which may reduce the ability to treat the animals effectively. Research conducted at the University of Guelph proved that using a telemetric bolus inserted in the animal’s rumen alerts managers to the possibility of illness long before it can be visually observed. By using the bolus, pen riders can focus on pulling the “at-risk” animals. As well, more animals can be monitored at once via computer and no animal is overlooked.

“The telemetric bolus will essentially monitor the animal’s health for the rest of its life,” explains Dr. Brian McBride, the lead researcher at the University of Guelph. While the Guelph research focused on dairy animals, Dr. McBride says the application would be highly effective in feedlots where it is difficult to monitor every animal regularly.

“By the time symptoms of illness are seen visually, the animal has probably already been sick for many days,” Dr. McBride continues. The bolus monitors temperature and an increase is an indication of health issues.

The use of telemetric bolus technology is not new having been used for many applications in research situations. However, researchers and industry are seeing applications for the technology that make sense commercially, which led to the Guelph research. Originally, interest was to monitor dairy cows, but it was realized that the technology could be very useful in feedlots as well.

“While it is true we have not had a lot of success getting the bolus technology into commercial feedlots, we have proven its value in feedlots at Colorado State University and Oklahoma State University,” admits Bill Ardrey of SmartStock in Pawnee, Oklahoma, the manufacturer of the bolus. “It may be that the bolus would work best in a cow-calf operation because it would detect temperature changes in cows in heat which would then allow for a 12-hour window for AI.”

The technology seems to have the best application in detecting temperature changes that can indicate the onset of illness or heat. The researchers at the University of Guelph believe the commercial application of the bolus technology could benefit the cattle industry. “At some point this technology needs to be given a chance,” comments Dr. Ousama AlZahal, another of the university researchers. “In feedlots the sick animal could be removed before infection spreads and, by treating the animal early, feed efficiency could be maintained.”

At Oklahoma State University, extension and research beef cattle specialist Chris Richards says their research team has been using bolus technology in their feedlot for five years. “Our intent in using the bolus is to aid in more accurate and early detection of health problems,” he says. “Our feedlot deals with high-risk calves that have been recently weaned, are from multiple sources, or have been transported long distances. We have determined the boluses are capable of detecting Bovine Respiratory Disease and Bovine Viral Diarrhea Virus by monitoring healthy calves that were intentionally exposed to the diseases. In trials where we monitored temperatures of calves that were pulled, based on visual observations, temperature indicated illness 12 to 48 hours before the onset of visual symptoms.”

Each bolus has a bar code that is linked to the animal and transmits a signal to a computer that can be set to record the temperature of the animal at set increments. The computer software can be programmed to send an alert if the temperature of an animal changes significantly. The boluses have long-life batteries and can work for up to six years, which is a benefit to the dairy industry. However, in the beef industry, unless used on breeding stock, the bolus would be lost as soon as the animal reached market weight. Richards says if the bolus is recovered, it can be reassigned to another animal and reused, which helps to reduce the cost.

At present, SmartStock sells a bolus for US$35 based on a purchase of 1,000 units. Feedlot operators would prefer a much lower price point. However, the cost is recovered if an animal is not lost to illness and can be sold at a healthy market weight. Richards points out that recovering the bolus and reusing it reduces the price the more often it is reused, but recovery can be messy and is not guaranteed.

“A calf will only be in the feedlot from about 100 to 250 days,” Richards explains. “The most valuable time to have health information is in the first 45 to 60 days, so the cost for the bolus would be 50 cents per day for a one-time-use item. Our most expensive anti-microbial treatments are $20 to $25, if we medicate immediately on arrival. Therefore, from a commercial standpoint, the bolus technology is not economical. However, from a research perspective, this technology is giving us valuable information on preventing, detecting, and treating animal diseases by more accurately defining onset of illnesses, responses to interventions, and responses to management practice changes.”

Clearly, the technology is still out of reach cost-wise for the average feedlot, but it may have some valuable application in monitoring the health of valuable breeding stock. Dr. AlZahal believes the cost will be offset in the protection of animals by detecting disease early. Perhaps like much of today’s technology, now that it is being tested for commercial use, the cost will slowly come down as manufacturing improves, the software is tweaked and the number of boluses being manufactured increases. The Guelph research proved the technology is a valuable tool, now the tool needs to be cost effective.


Temperature indicated illness 12 to 48 hours before the onset of visual symptoms

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