The Axolotl and the Axolotl Facility University of

The Axolotl and the Axolotl Facility University of Kentucky Ambystoma Genetic Stock Center

University of Kentucky Ambystoma Colony • Mid 50 s - Axolotls come to Indiana • Mid 60 s - Started supplying embryos • 1969 - 1 st NSF grant to fund Colony • 1979 -1999 axolotl demand for grows • 2005 colony relocated to Univ of Kentucky

Ambystoma mexicanum Mexican Axolotl

Ambystoma tigrinum Tiger Salamander

The Axolotl Life Cycle

The Axolotl Blastula Embryonic stages Hatching Tailbud Gastrula Neurula

The Axolotl hatchlings

The Axolotl One week old larvae white and albino

The Axolotl gills and lungs Wild-type Axolotls

The Axolotl Males • Slim • Swelling around cloaca Females • Rounded (filled out with eggs) • No Swelling around cloaca

The Axolotl • Weight of adults: 150 -250 gram average but can get up to 400 grams or more • Length of adults: 25 cm (10 inches) average • Breeding begins at 1 -2 years – males : monthly – females: every few months • Breeding slows after 6 years of age but animals will continue to spawn if in good health • Life Span…. . ? ? ?

Three pigment cells The Axolotl Wild-type • Melanophores - dark pigment • Iridophores - reflective pigment • Xanthophores - yellow pigment Albino White

The Axolotl Facility • Water • Temperature • Housing • Food • Lighting

The Axolotl Facility Water • Chlorine removed by letting stand • Ammonia and chloramines chemically removed – Treated water usable immediately • Water conditioning chemicals – Helps maintain slime coat – Removes copper • No distilled water for larvae and adults, there aren’t enough minerals – Distilled water ok for embryos Salt additions (not necessary when using hard water): • Modified Holtfreter’s solution contains • • Na. Cl Mg. SO 4 Ca. Cl 2 KCl • Good for colony situations • Good for surgical recovery

The Axolotl Facility Temperature o o • 18 -22 C • Embryonic development can be regulated by refrigeration o • Larval growth can be stunted if reared too cool (>15 C) • Refrigeration useful for bleeding or sick animals

The Axolotl Facility Housing Consider: – Individual vs. Group housing – Glass vs. Plastics – Hiding places – Animal identification

The Axolotl Facility Housing Individual vs. Group Housing • Animal injuries • Space • Disease Control • Breeding Control • Effected by research needs

The Axolotl Facility Housing Individual Housing Pros and Cons Pros • No chance of injury from other axolotls • Better disease control • Necessary after surgery Cons • Time consuming care • Space consuming • Less space for individual animals

The Axolotl Facility Housing Group Housing Pros and Cons Pros • More swimming and floor space • Space efficient • Time efficient Cons • Chance of injury increased • More chance for the spread of disease • Less Breeding Control

The Axolotl Facility Housing Group Housing Pros and Cons Con Pro Spermatophore Bevy of Beautiful females

The Axolotl Facility Housing General Guidelines for Adults Axolotls • Axolotls need at least 2 liters of fresh water per animal every other day • Bowls should be at least 22 cm (~9”) in diameter • Tanks should have about 300 sq. cm (40 -50 sq in) of floor space per animal • Tanks and bowls should be covered or water level well below the top to prevent jumpers

The Axolotl Facility Housing General Guidelines for Embryos and Larvae • Embryos: 100/1 L in a 22 cm (9”) wide bowl, topped off until hatch • Hatchlings: 50/1 L in a 22 cm wide bowl, changed daily • Thin animals as they grow • 5 -10 cm larvae: 1/1 L in a 15 cm wide bowl, changed daily

The Axolotl Facility Housing Glass vs. Plastics • Glass is very easy to clean and doesn’t promote the growth of bacteria as do plastics • Glass is good for post-operative care and for the care of sick or injured animals • Some plastics leach chemicals toxic to amphibians • Glass is very expensive and has a shorter life than plastics • Plastics are easier to work with, less dangerous, and more efficient than glass

The Axolotl Facility Housing Hiding Places • Contribute to health by reducing stress • Plastic plants • easy to clean • provide shelter for whole tank • PVC sections

The Axolotl Facility Housing Animal Identification • Natural Markings • Individual Bowls • Personal Identification Tags - microchip transponders - place in back or in abdomen

The Axolotl Facility Lighting • 14 light/10 dark - 12 light/12 dark • Manipulate lights to encourage breeding

The Axolotl Facility Feeding Food should be: Do’s and Don’ts • Smelly • Soft/moist • Hang together in water • Sink • Parasite free • Low fat, high protein • Balanced • Don’t feed fish from bait shops • Don’t feed beef heart or liver as main diet - not complete • Axolotls love earthworms • Pellet chows work very well as growers for adults • Use brine shrimp for larvae up to 4 cm

Axolotl Health Anaesthesia and Euthanasia • Benzocaine • MS-222 • . 1% for anaesthesia • . 3% for euthanasia • Important to p. H adjust to between 6 -8

Axolotl Health Treatments • Good husbandry is the best preventative • Refrigeration • Mercurochrome as a disinfectant • Antibiotics • Amikacin, Gentamicin • 5 mg/kg body weight, injected IP, every 48 hours for 3 doses • Enrofloxacin - not tested enough with axolotls • Penicillin - safe but limited spectrum • Avoid tetracyclines - damages skin • Avoid copper containing treatments

University of Kentucky Ambystoma Genetic Stock Center ambystoma@uky. edu

The Axolotl