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Tips for Successful Breeding and Colony Management. Office of Lab Animal Resources University of Colorado Denver AMC Tracy Haney, CVT, RLAT Holly Goold, CVT, RALAT. Environmental Factors. Drop in production (October-March) Even though mice are in a controlled environment
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Tips for Successful Breeding and Colony Management Office of Lab Animal Resources University of Colorado Denver AMC Tracy Haney, CVT, RLAT Holly Goold, CVT, RALAT
Environmental Factors • Drop in production (October-March) • Even though mice are in a controlled environment • Light cycles, temperature, humidity, etc • Smaller, less frequent litters.
External factors • Odor from staff (perfume/cologne, cigarette smoke) • Entering housing room after hours (8p-6a) • Mice mate 5-6 hours after dark cycle starts • Conversations/music/phones in housing room • Amount of traffic in housing room • Shoving cages anywhere on rack • Inexperienced /unconfident handling of mice
Cage location • In room • If possible, away from door and ATS • On rack • Lowest row on rack, away from lights • Keep separate from experimental mice • Less cage movement
Enrichment • Helps decrease stress/increase pup survival • Manage their environment • Mimics natural nest • Brown paper shred • Mouse huts/paper towel rolls • Con • Remove before cage wash if combined with nestlet • Must use ~6-8 grams of shred • Hard to visualize litters
Breeder Set-up • Setting Breeders • Mice and Rats • Females: 5 weeks to 8-10 months • Breed females before 3 months of age • better fertility • Litter sizes decrease with age • Genetic issues • Poor lactation in homozygous moms • Males: 6 weeks to 12-18 months • Set-up • Set in a clean cage • Add enrichment/breeder chow • “Charged” cage
Types of Matings • Continuous pair • Pros • Post-partum estrous cycle • Litters every 21 days • Cons • Possibility of two litters in the cage • Non-Contiuous • Pros • No double litters • Con • Have to remove the male • Less frequent litters • Triad • Pros • Sister females, synced estrous cycle • Cons • Unrelated females • 1 Dominant female • Requires protocol approval • Male rotated between cages • Miss females’ post-partum estrous
Breeding Tips • Lithgow “Check for Pups/Wean” cards are provided in housing rooms • Track births, pups lost, and successful weaning • Tracking fertility
Breeding Tips • DO NOT retire old breeding pairs until after confirming successful breeding of new pairs • Retiring old breeders • Set new breeding pair one month before retiring old • Ensure successful breeding before ending old pair • Stagger setup • Insurance to always have mice
Maintaining a Litter • Avoid extra handling of litter • < 3 days old • Reduce litter size when able • One sex vs phenotype • Genotype early: 7-10 days • Footpad tattoos/tail snips • Cage changing • Anticipating pup birth • Transfer half of the old nest with pups • Fostering • Keep environmental noise levels “even”
Troubleshooting • Pup death • Stress to female • Disturbing the cage frequently • Removing male right before or after pup birth • Separating females from cage right before or after pup birth • Manipulating pups- touching pups within a week of birth • First-time mom (C57 background) • Transgenic lines • *Please remember that you must remain compliant with the IACUC rodent overcrowding policy. If multiple litters are in the cage, you are obligated to separate them for animal welfare reasons regardless of the risk of cannibalism or maternal neglect. Therefore, it is essential that you separate mothers prior to the litter being born.
Breeding Specialists For information on breeding services or training/help needed, please contact: Tracy Haney for Barrier and R2: tracy.haney@ucdenver.edu, 303-724-3982 Holly Goold for RC-1: holly.goold@ucdenver.edu, 303-724-2237
Why do my mice eat their babies?!?Diagnosing lactation problems in miceTown Hall meeting, Oct. 24, 2013 Jenifer Monks, Ph.D. Jenifer.monks@ucdenver.edu
How could my gene mutation be affecting lactation?!?Gene mutations may alter mammary function: off-target • Cell cycle, proliferation, cell death-> mammary development • Cell polarization, secretion, metabolism-> milk production • Neurological/behavioral-> mothering, stress, let-down, feeding behavior in pups Developmental Stages of the Mammary Gland Embryonic Pubertal Adult Involution Pregnancy Lactation …use wild-type, heterozygous or hemizygous females whenever possible
Indications the Dam may be having trouble feeding her pups • Normal Estrous • Get pregnant, stay pregnant • Normal delivery, normal litter size • Pups scattered around cage • Die peri-partum (shortly after birth) or are cannibalized • Failure to thrive • Wean runty or with bald butts • Only alternate litters survive
Tips for success: • Nesting material: thermoregulation, security, pheromones • “Do Not Disturb” pink cards peri-partum: reduce stress http://med.stanford.edu/ism/2012/march/mice.html Making mice comfy leads to better science, researcher says “The shape of the nest tells an experienced person whether the animals are too hot or too cold, whether they are sick or whether they are about to give birth,”
Do they have milk bands? No? dead by day 3
Tips for success: 3) Careful record keeping Estrous 4-5 days Gestation 18-21 days Lactation 21-28 days (if housed with male, remove weanling animals at 20 days old)
Gestation time of your strain is known: A/J 20.5 129 20.2 Balb/c 20.1 C57BL6 19.6 FVB 18.7 Murray SA, Morgan JL, Kane C, Sharma Y, Heffner CS, et al. (2010) Mouse Gestation Length Is Genetically Determined. PLoS ONE 5(8): e12418.
Mouse weighing to track reproduction:Normal gestation is 19 days- Co-housed with male-implantation delay when concurrently pregnant and lactating
** n = 8 litters Dam-Litter body weights: non-invasive monitoring mid-pregnancy resorption of litter Compromised milk production Lactation Failure and Early weaning by mother
Cross-fostering to improve breeding success CD-1/ICR & Black Swiss mice make good foster dams Timed matings of both strains Remove transgenic pups from biological mother and give to foster dam as soon after birth as possible Warm in hand if cold and scattered Roll in soiled bedding of foster dam Remove unneeded pups to normalize litter size-10 teats, match natural litter size Place carefully in nest
Timed mating of mice Photo courtesy Mouse Fancier website http://www.fancymicebreeders.com/mousefancierforum/phpBB3/viewtopic.php?f=11&t=756 Four stages of estrous in BALB/cByJ mice. The four stages of estrous are shown for an albino strain (proestrus (A), estrus (B), metestrus (C), diestrus (D)). Mouse estrous cycle identification tool and images. 2012. PloS one
Why Care about breeding efficiency? • Save time • Save money: $0.83/day/cage • Better animal care = better science Tips for Increasing Efficiency and Cutting Costs • Do not set up breeders without knowing their genotypes. • Know what genotypes you are trying to produce and the number you will need. • Overproduction = wasted animals and $$$ • Underproduction = wasted time • Account for seasonal variation and holiday schedules • Keep a reserve of breeder-age animals. • Retire/replace unproductive breeders (record keeping, 2 consecutive lost litters), unused experimental animals, and animals of useless genotypes. • Do not keep singly housed animals • Keep a calendar for breeders and experiments • * Collaborate * Know which animals are Raptor Safe Contact OLAR if you have unused animals that can be donated to training protocols
Still having trouble? Ask for help! • Online resources-Jackson Laboratories • OLAR: Care staff, vet techs, breeding specialists • Colleagues • …Andrew Lewis • Toothless mice • Mayonnaise milk Jenifer.monks@ucdenver.edu
Transgenic and Gene Targeting Core Website: www.medschool.ucdenver.edu/Transgenics Email: Makeamouse@ucdenver.edu
Transgenic and Gene Targeting Core www.medschool.ucdenver.edu/Transgenics
Core Personnel Peter J. Koch, PhD Professor of Dermatology and Cell & Developmental Biology, Director The Charles C Gates Center for Regenerative Medicine and Stem Cell Biology University of Colorado Saiphone Webb, BS Senior PRA, Laboratory Manager Embryo Manipulation Services Embryonic Stem Cell Development and Production Abby Zamora, CVT, LAT PRA Colony and Data Management Embryo Manipulation Services Abhilasha Jain, MS PRA Embryonic Stem Cell Development and Production
How You Can Lose Your Mouse Line • The transgene stopped working; loss of phenotype (e.g. promoter methylation) • There is a change in the phenotype of your mice (e.g. gene drift) • A disease outbreak • Breeding has stopped and you’re left with only few male and female mice.
Solutions • Order replacement mice from a vendor(if the line is available) • Request the mice from a colleague working at another University – (this will take time to breed up the mice for experiments) • Start over and generate the line from scratch(this will take more time and money) • Re-establish mouse line using previous frozen sperm(IVF) or embryos
Methods and Requirements For Cryopreservation and Line Rescue Services
Transgenic and Gene Targeting Core www.medschool.ucdenver.edu/Transgenic makeamouse@ucdenver.edu Supported by: NIH (SDRC, CCTSI), Gates Center, SOM, Dermatology Department, Service Fees