Report Animal Concerns

Acetates: A Means of Communication

Facilities Husbandry ULAM

Picture of animal room acetate box with multi-colored blank acetates

How can you ensure your animals receive the special chow your research requires? How do you tell your room husbandry technician that you don’t want your breeding cages disturbed immediately following a new birth? How do the veterinary personnel know which cage needs immediate attention due to a health concern?

The answer to these questions and more is through the animal room communication system!

The Unit for Laboratory Animal Medicine (ULAM) utilizes acetates, which are colored, plastic cards placed over animal cage cards to communicate information between lab personnel and ULAM personnel.

There are five different acetate colors used – red, blue, yellow, green, and clear. The meaning conveyed by an acetate varies by the color and orientation, i.e. whether the acetate is placed horizontally or vertically over the animal cage card.

When multiple acetates are placed on one cage card, they must be placed from smallest to largest in size. This is to allow easier viewing of each acetate when multiple acetates are used; red acetates are always placed in front for cages with multiple acetates to ensure priority.

Below is a table indicating what each acetate color & orientation means

A similar guide will be located in each animal room for reference. While the meaning of each acetate is crucial, who can remove an acetate is also important to understand. Looking at the last two columns of the table below, it can be ascertained that the person who places the acetate is typically the person responsible for removing that acetate.

When manipulating cages, extra care must be taken to ensure acetates are returned should any fall off.




Who Places
the Acetate?

Who Removes
the Acetate?

Horizontal Red

Health concern or abnormality noted and veterinary personnel notified

Veterinary personnel have been contacted

ULAM husbandry personnel

ULAM veterinary personnel

Vertical Red

Veterinary personnel have examined animal and short-term follow-up is needed

Veterinary personnel are working to determine a management plan for the animal

ULAM veterinary personnel

ULAM veterinary personnel

Horizontal Blue

Overcrowded cage conditions requiring attention by the
next business day

ULAM places the acetate and will separate the next business day, unless already done so by the lab

ULAM husbandry personnel

ULAM husbandry personnel or lab personnel ONLY IF cage is appropriately separated


ULAM marks single housed animal that does not have cage label identifying justification for single housing

A date and single housing exemption code must be recorded on a blue tab associated with the cage

ULAM husbandry personnel

ULAM husbandry personnel or lab personnel ONLY IF cage is properly labeled


Deviation from ULAM Standard Operating Procedures (SOPs)

May or may not correspond
to a Special Treatment or Procedure (SToP) Form

Lab personnel or ULAM husbandry or veterinary personnel

Lab personnel may remove ONLY ones lab has placed.

ULAM removes ONLY ones ULAM has placed


Veterinary personnel place these acetates when they are providing monitoring or treatment of a health condition

Veterinary personnel must assess animals minimally every 14 days

ULAM veterinary personnel

ULAM veterinary personnel


Condition observed, noted, and no monitoring or
treatment is needed

Common conditions are kinked/curly tail or animals with red skin phenotype

ULAM husbandry or
veterinary personnel

ULAM husbandry or
veterinary personnel


  • Contact the ULAM Training Core at or (734) 763-8039 if you would like additional training on the use of acetates in animal care rooms.
  • Additional questions about the use of acetates in your specific animal care room should be directed to your facility’s ULAM Husbandry Supervisorrequires Level-1 U-M login credentials

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