Management of X. laevis Flashcards
What family does the African clawed frog belong to? How many species are there?
Family Pipidae, 18 species.
Where are research Xenopus exported from?
Cape, South Africa
What environment does Xenopus prefer? What niche does it fill?
Still, opaque, vegetation-filled water. In lakes devoid of fish, Xenopus has evolved to fill the fish niche.
What temperatures are Xenopus acclimated to? What occurs with temperature stress? How do Xenopus cope with temp extremes?
Tolerates wide temp range. Adults stressed at prolonged temps less than 14C (57C) and greater then 26C (81F). Decrease in oocyte quality observed. If temps are too hot (30C, 86F), will evacuate pits in cool mud. In drought, estivates.
What pH and salinity can Xenopus handle in the wild?
Will breed in acidic and alkaline water, but tadpole survival drops in water with a pH <5. Will tolerate elevated salinity (40% seawater) for short time.
What is unique about the fifth toe of Xenopus?
Much longer than the tibia.
How do female and male Xenopus compare?
Females larger. Have a large cloacal papillae. Males develop dark inner surface of their forearms (nuptial pads).
What do the skin secretions of Xenopus include?
Thyrotropin releasing hormone, caerulein, and xenopsin. Magainins - antimicrobial compounds.
How does Xenopus feed?
Lacks a tongue. Lowers buccopharyngeal pressure and opens mouth, suctioning prey in. Shreds prey with hind claws and uses front feet so sweep food into mouth.
Describe Xenopus eyes.
Dorsally-located, lidless, and adapted for vision in air, not water.
Describe scent detection in Xenopus.
Two olfactory cavities - One for scent in water, other for airborne odors.
Describe the lateral line in Xenopus.
Located dorsally and ventrally, retained in adult animals.
What is the vocal apparatus of Xenopus designed for? How do animals vocalize.
Underwater sound production. Vocalize by clicking.
Describe the social structure of Xenopus.
Territorial, form dominant/subordinate hierarchies.
Describe respiration in Xenopus.
Large lungs and heart. Must come to water’s surface to gulp air, as cutaneous resp is not well developed. Tadpoles develop and utilize lungs as well as gills for breathing.
How does Xenopus adapt physiologically during drought?
Produce urea instead of ammonia. When water available, reverts to production of more toxic ammonia, which rapidly dissipates in water.
What is the life span of Xenopus?
Greater than 10 years in wild, 20 years in captivity.