Dwarf Hamster Husbandry and Care

Last Review Date: January 6, 2021


I. Purpose


This Standard Operating Procedure (SOP) outlines the animal care requirements associated with the daily husbandry of dwarf hamsters to ensure consistent and uniform care. This procedure applies to all personnel involved in the care of dwarf hamsters housed in the Laboratory Animal Resources (LAR) facility on the campus of the University of Montana.

II. Policy

It is a LAR policy to meet or exceed all federal, state, and local regulations and guidelines and to comply with all institutional policies and procedures as they apply to the use of animals in research. LAR personnel must pass on-line animal training modules and attend applicable training in animal care and use, occupational health and safety, and equipment operation prior to performing activities outlined in this SOP. Animal housing rooms should be entered using appropriate personal protective gear for the species and disease or hazard containment level.

III. Husbandry and Care Procedures

Morning observation:

  • Record room temperature: room temperature should be no higher than 67oF, preferably ~64oF (if the temperature exceeds 67oF, contact Dr. Good or someone in his group immediately and inform the Facility Manager).
  • Observe animals for signs of disease, illness, or injury.
  • Check to see if dwarf hamsters are eating and drinking water.
  • Light timers are on a 14L-10D light cycle. Do not touch automated light timers.
    • Contact the Facility Manager as soon as possible if a light issue arises.
    • The HS005B light cycle is adjusted by the investigator to shorten daylight hours.  DO NOT enter the room during the dark cycle posted on the door.

Daily routine

  • Observe animals for signs of disease or illness as above.
  • Top off all water bottles (if ½ full or less) daily and check that lixits are free of debris before replacing on bottles.
  • Perform any vet checks, or additional care instructions if applicable
  • Wipe down counter surfaces with Peroxigard.
  • Sweep and mop the floor with Peroxigard in the mop bucket.
  • Empty trash.
  • Replenish bedding and feed bin as needed (check for the expiration of feed) and fill out an index card on bedding and food bins after sanitizing containers and refill (once monthly at a minimum).
  • Fill out the checklist sheet, census sheet, and initial daily log.
  • Report any animal illness or deaths to Dr. Good or someone in his group and the Facility Manager and Attending Veterinarian as soon as possible.

Weekend routine

  • Follow daily routine except do not mop the floor.

Every 2 weeks

  • Complete cage change.  Exchange cage with clean dwarf hamster cage.
  • Prepare cages with clean autoclaved SaniChip bedding, clean feeders, clean water bottles, and new autoclaved enrichment devices (sunflower seeds, nestlets, wooden blocks, paper towel rolls, or egg carton houses to each clean cage).
  • Personnel in the Good Lab do the actual cage changes for the animals. 
  • Wash dirty caging unit, bottles, and feeders in the cage washer.  Store clean items in HS007.
  • Change RAIR Rack filters every other month.  Document RAIR Rack information (fans, temperature, filter usage, performance, operating hours) on room clipboard on the first of every month.

Monthly

  • All Surface Clean (ASC) animal housing rooms, wash walls, feed bins, sinks, counters, light diffusers, floors, and threshold with Peroxigard. Let stand for 3 minutes and rinse with clean water.  Dry surfaces with paper towels if necessary.
  • Initial checklist, ASC sheets, and daily log.

Wet Box

  • Get a clean hamster box from the Clean Cage Room (HSB 007) and a new clean water bottle,  lixit, and cage lid
  • Fill the new clean box with bedding and add new enrichment
  • Fill the new water bottle and test to make sure the new lixit isn’t leaking
  • Transfer the hamsters from the wet box to the dry box.
  • Transfer over food hopper, fill food if applicable, replace leaking H2O bottle with a new lixit
  • Replace the hamster box into the appropriate slot on the rack
  • Document cage location on the daily log sheet
  • Take dirty caging and materials to the HS dirty cage room

IV.  Breeding

It is common that a pair will not start breeding for over a month (sometimes longer. Phodopus seem to be much more particular about their pair bond than mice do. We often supplement with sunflower seeds when first pairing, and it seems to help them with initial introductions. Once a pair has produced a successful litter, we try to keep those same individuals paired. However, if two are not successful after 2-3 months, we will separate them for 20 days to make sure there is no litter and try to pair with other individuals. Sometimes hamsters just don't like each other enough to breed. Three months seems a reasonable age to start breeding, and we make sure they have their first litter before 6 months (otherwise they sometimes never breed).

Once the females are pregnant, do different things for each our two species.  Phodopus campbelli has bi-parental care, and pups fare better if both parents are in the cage pre-weaning. We have to be careful to wean a litter before the next one is born, and strategize about litter number because it is easy to get overwhelmed. With our other species, P. sungorus, the females become territorial while pregnant, and if we do not remove the sire early enough sometimes the dam will attack him. Normally, the first sign of female aggression is that the male is outside the nest. We remove the male before he is injured, and the female gives birth and performs parental care on her own. We then re-cross the same animals to generate the next litter.

Gestation time is around 18 days for both species, but we have seen litters born with slightly more time between splitting a pair and birth, so there may be delayed implantation or variation in gestation time.