Well Cow Limited

Background

The need for a pH monitor in the dairy cattle sector

Up to 20% of dairy cows will develop acidosis in the period after calving. A condition known as sub-acute rumen acidosis (SARA) may also be present in larger numbers of cows. The effect of this is to reduce milk fat and total output and in some cows to cause more serious disease such as ketosis, lameness, displaced abomasums, mastitis and sub-fertility. The cost of these diseases is estimated at $150-350 per cow affected.

SARA is an increasing health problem in most dairy herds in the US. Results from field studies indicate a high prevalence of SARA in high-producing dairy herds as producers respond to the demands for increased milk production with higher grain, lower fibre diets that maximize energy intake during early lactation. The economic cost associated with SARA can be staggering. It is estimated that SARA costs the North American dairy industry between $500 million and $1 billion annually. The challenge for dairy farmers and dairy nutritionists is to implement feeding management and husbandry practices that prevent or reduce the incidence of SARA, even in high-producing dairy herds where higher levels of concentrate are fed to maximize energy intake.

The capability to monitor pH levels in a small number of cows within a herd will provide the farmer and veterinarian with important information which will be indicative of the state of health of the herd as a whole. If and when, the sentinel cows exhibit increasing acidosis (eg a rumen pH of less than 5.5) the farmer will be able to adjust his feeding strategy to avert the developing problem.

Existing techniques for monitoring pH

Currently the only methods for monitoring the pH of a cow's rumen are either invasive veterinary procedures to collect samples for off-line analysis (lumbar puncture) or pH sensors connected by wire to data collection device external to the animal. The sensor and wire are inserted through a cannula or fistula (ie requiring surgery). These techniques are substantially inferior to the device being develop by Well Cow^TM.

• It is wholly unfeasible for a large number of dairy cows to undergo surgery for pH monitoring
• It is physically not possible nor economically viable to sample many cows by veterinary procedure

There is no other radio transmitter based device available on the market. Our discussions with academic researchers, including Prof Michael McGowan of the University of Queensland, has confirmed that there is an unmet demand for such a device. Dairy Australia researchers at University of Sydney state that developing a long lived rumen bolus for pasture management of their grazing cattle was a major priority.

Target User Groups

Dairy Farmers
As discussed above farmers have a need to monitor acidosis within their herds. This is not being achieved at present. As acidosis largely arises from feedstock factors it should affect a herd as a whole. Therefore if a farmer monitored a small number of cows he could reasonably infer the state of health for the herd as a whole.

As no device has previously been available it is difficult to estimate what proportion of cows would need to be monitored. It has been suggested that 10% might need to be monitored but Well Cow believes that 1% may be adequate.

In 2001, 2,800 herds of over 500 cows were responsible for 39% of milk production in the US, with 95,000 herds of less than 500 cows responsible for the remainder . (There are over 9 million diary cows in the US at present .)

Veterinarians
As well as being used by farmers as a preventative tool, the device will also be a useful diagnostic tool for veterinarians.

Academic researchers
Well Cow^TM has already engaged with academic collaborators using its existing prototype device to demonstrate the data which can be collected. This has prompted further interest from other researchers.

Other uses for the device

Having been designed to survive in a very hostile environment - a cows rumen - the device is extremely rugged and could be used in many other areas. The most immediate opportunities are in the area of environmental and water monitoring. Informal discussions with academic researchers in this field have prompted considerable interest.

Over the past 4 years Well Cow^TM has developed a device uniquely able to meet the challenging requirements of being able to operate for long periods in the very harsh environment of the cow's stomach and capable of measuring the acidity (pH) within a cow's stomach, storing the resulting data and then transmitting it by radio signal to a handheld receiver from which it can be sent to a computer for analysis.

The development of this device has been part funded by Monsanto, which has separately carried out a market analysis in the US to ascertain how such a device could be used by US dairy farmers. The conclusion from this market analysis is that :

• A pH monitor could be an important tool for monitoring the health of dairy herds to identify early onset of SARA.
• Devices would be inserted into healthy "sentinel cows" within a herd to provide an early indication that SARA may be occurring.