March 28, 2006
Laboratory 'cows' facilitate research efforts
(Pronouncer: Amer AbuGhazaleh is "AH-mare ah-boo-gah-ZAH-lah")
CARBONDALE, Ill. -- Animal scientist Amer AbuGhazaleh keeps four "cows" in his lab at Southern Illinois University Carbondale. They're cheap to feed, easy to clean up after, and they take up hardly any space, though they have to be washed with care — they break easily.
The "cows" are actually custom-built combinations of glass bottles, tubing and controls set up to mimic what happens in the rumen, the first compartment of a cow's stomach. Each bottle has a tube that conveys food into it, a tube that transports "saliva" to it to aid its digestion and a tube that carries waste out of it and into a white plastic bucket.
While AbuGhazaleh has a whole herd of Holsteins out at the SIUC dairy center, his lab "cows"(more properly called "fermenters") have certain advantages over live animals when it comes to his research.
"The biggest of these is cost," AbuGhazaleh said.
"A cow has a 50-gallon stomach. It can eat 60 pounds of food a day, where the fermenter uses less than a quarter of a pound."
There's also the matter of control.
"If a cow decides not to eat one day, there isn't anything I can do about it," AbuGhazaleh said. "If I'm in the middle of an experiment, I have to start over again.
"Also, you see a lot of variation within animals. You can have four cows, but they won't be alike. In my system, I have designed my ‘cows' to be identical.
"Plus, they're easier to sample, and you never have to call a vet."
AbuGhazaleh is now running his first experiments in the fermenters since he and a graduate student put them together last year. The tests, part of a pilot study funded with SIUC seed money, complement a larger Illinois Council on Food and Agricultural Research project aimed at boosting the production of healthy fatty acids in cow's milk.
While AbuGhazaleh's C-FAR research focuses on the effects simple dietary changes could have on milk content, his smaller study tries to pinpoint how and why those changes work.
"If we can understand that, we can (use that knowledge and) get more of the good fatty acids," he said.
Because microbes in the rumen produce most of the desirable fatty acids found in milk, AbuGhazaleh's lab "cows" should prove particularly useful. By adding molecule-sized markers to the "feed" he puts in his fermenters, he can track what happens in the digestive process.
"These markers are very expensive — between $1,000 and $5,000 per gram," AbuGhazaleh said.
"One gram in a cow's stomach would be so diluted it would not work as a tracer, but the fermenter has a volume of less than a liter (a little more than a quart)."
Although it takes only 10 days to collect the data he needs, AbuGhazaleh will repeat the 10-day data collection phase three additional times, both to make sure that the numbers come out largely the same in each phase and also to lend them some weight, as the experiments involve only four "cows."
"It would be better to have 16 fermenters, but the cost would be prohibitive," AbuGhazaleh said.
Leading in research, scholarly and creative activities is among the goals of Southern at 150: Building Excellence Through Commitment, the blueprint the University is following as it approaches its 150th anniversary in 2019.