ANN ARBOR, MI -- Within six months, University of Michigan animal testing laboratories accidentally lost a mutant rabbit, poisoned nearly 11,500 zebra fish with bleach, caused 53 mice to die of thirst and gave an unknown number of mice terminal gastrointestinal cancer, federal records show.

Four legally required letters detailing the research animal losses, which occurred between March and September of last year, were mailed to the federal Office of Laboratory Animal Welfare by the UM Research and Animal Care and Use offices.

Stop Animal Exploitation Now, an animal advocacy group, obtained the correspondence through records requests sent to the federal Office of Laboratory Animal Welfare and is now calling on UM President Mark Schlissel to do an independent investigation.

“These incidents of negligence indicate serious systemic issues within the University of Michigan animal experimentation system,” says a March 20 letter sent to the president and Board of Regents by Stop Animal Exploitation Now Director Michael Budkie.

Budkie said all registered laboratories that receive funding from the federal government are required to self report certain incidents that result in the death or loss of lab animals. Stop Animal Exploitation Now regularly analyzes those reports.

“We are not aware of any other institution that has had this excessive a number of deaths in such a short time,” Budkie told MLive."

While the advocacy group calls the series of incidents an indicator of “serious systemic issues,” UM describes them as “isolated incidents.”

" We deeply regret the loss of these animals, most of which were zebrafish," university spokesman Rick Fitzgerald said. "Upon discovery in 2018, these incidents were corrected immediately by our animal care team, and corrective action plans were put into place to prevent any future issues.

“The university has many strong policies and controls in place to monitor all projects involving the use of animals.”

Summary of UM reports to Office of Laboratory Animal Welfare:

Sept. 4, 2018: Water from a reverse osmosis pressure tank was used to fill an 80-gallon bleach sanitation tank. Tubing from the pressure tank was left in the bleach reservoir and inadvertently pumped into a fish tank resulting in the deaths of 11,548 zebra fish.

June 13, 2018: While cleaning the cages of lab mice, workers accidentally dislodged the water source from a rack of mice. Because of this, 53 mice died of dehydration.

May 7, 2018: While conducting an animal health check on April 2, the caretaker discovered that a rabbit bred with artificially introduced DNA was missing. “The location of the animal is unknown," the lab concluded following a search of the premises.

March 18, 2018: A study of gastrointestinal cancer involved the development of internal tumors in mice. Preset indicators established when mice were expected to be removed from the study, but nine mice were inadvertently left in the study too long and developed gastrointestinal tumors that required them to be euthanized.

UM’s full statement:

The University of Michigan recognizes that working with animals to advance human and animal health is a privilege that requires constant diligence and a commitment to the highest standards of animal welfare in all aspects of our research and teaching. We deeply regret the loss of these animals, most of which were zebrafish.

Upon discovery in 2018, these incidents were corrected immediately by our animal care team, and corrective action plans were put into place to prevent any future issues. The university has many strong policies and controls in place to monitor all projects involving the use of animals.

As part of that oversight, and in the interest of full transparency, U-M self-reported each of these events to the National Institute of Health’s Office of Laboratory Animal Welfare (OLAW). OLAW reviewed these matters and found that U-M took all necessary steps to self-report and correct these isolated incidents.

Again, we deeply regret the loss of all animal lives. We will continue to explore new approaches and refine our practices to maintain our commitment to not only achieving, but exceeding, national and professional standards in animal care and use.