Amphibians Physical Examination

Handling Concerns-Amphibian Skin Permeable Moistened, powder-free gloves should be used to protect the amphibian’s skin from trauma and the handler from secreted toxins. -nicotine -cleaning supplies Delicate Secretion Frogs > susceptable than salamanders to env’tal and topicl toxins Nicotine== bad in small frogs PAF- irritation to skin of people sensitive to their toxins, over time in captivity lose ability to produce toxins, wash hands, use latex gloves -Permeable Skin -Delicate Skin -Location of Restraint (gills in larvae and some salas, tail in salas, frog-kick back) ...bone and mm injuries -Infectious Disease and Toxins (Salmonella, Mycobacterium spp., Chlamydia psittaci) ....toxins enter thru PO or eyes METHODS OF PHYSICAL RESTRAINT: Anurans. Medium and large size frogs and toads (those about 5 grams and larger) should be grasped around the waist with the hindlimbs fully extended. The animal should not be allowed to bend (flex) its hip and knee joints, since this would allow it to kick. Caudates. Medium and large size salamanders (those about 5 grams and larger) should be grasped in the middle of the body between the forelimbs and hindlimbs. Larval and neotenic salamanders should never be grasped around the head or neck, because the gills can be easily damaged. Under no circumstances should salamanders be grasped by the tail or picked up by the tail. Larvae. All larvae (including tadpoles) should be handled with nets or scoops. For examinations, the larvae should be placed in a clear plastic bag with a mild amount of water. Alternatively, larvae may be sedated with an anesthetic and examined in a dish or bowl of water. As much as possible, larvae should be examined only while they are in water. Larvae should not be grasped with bare hands. Frogs and Toads. All amphibians can be expected to struggle following capture. For anurans, there is a danger that vigorous kicking with the hindlimbs can cause joint dislocations or a broken (fractured) back; broken backs are a well-documented and major problem in another species that moves by hopping---rabbits. Therefore, proper restraint of anurans, first and foremost involves inhibiting their ability to kick. Salamanders. For salamanders, there are three major dangers associated with handling: 1) loss (automizing) of the tail, 2) damage to the very delicate external gills (in neotenes), and 3) back injury during whip-like thrashing movements. 2

Nicotine Toxicity Tadpole and hypercapnic challenge -Brain stem: ventilation -Surfacing frequency Systemic vasodilation Melanocyte Activation Developmental exposure to ethanol or nicotine inhibits the hypercapnic ventilatory response in tadpoles Author(s): Taylor BE (Taylor, Barbara E.), Croll AE (Croll, Andrea E.), Drucker ML (Drucker, Michelle L.), Wilson AL (Wilson, Ann L.) Source: RESPIRATORY PHYSIOLOGY & NEUROBIOLOGY Volume: 160 Issue: 1 Pages: 83-90 Published: JAN 1 2008 Times Cited: 0 References: 45 Citation MapCitation Map beta Abstract: Tadpoles, Lithobates (formerly Rana) catesbeiana, were held for 8-12 weeks in pond water that was either teratogen free or contained 0.15% ethanol or 30 mu g/L nicotine. The ventilatory and neuroventilatory consequences of these developmental exposures were assessed. Developmental exposure to ethanol or nicotine blocked the hypercapnia-induced increase in surfacing frequency typically exhibited by tadpoles, as well as the hypercapnia-induced increase in putative lung ventilation exhibited by isolated tadpole brainstems. It was specifically the hypercapnic ventilatory response, previously characterized as an increase in lung activity, that was affected by developmental exposure to these teratogens. Developmental exposure to ethanol or nicotine did not affect the frequency of surfacing or putative lung breaths exhibited by the intact tadpoles or their isolated brainstems when not subjected to a hypercapnic challenge. (c) 2007 Elsevier B.V. All rights reserved. http://www.puregreen.com.au

Handler Concerns Scratches and bites Infectious disease Toxic secretions: -Irritant -Hallucinogens -Vasoconstrictors -Neurotoxin

Toxin Uses For people: -Weapon (poison dart frogs) -Pharmacology (pain killers, psychoactive) For the animal: -Defense (unpalatable, paralysis) epibatidine-analgesic

Toxins Aposematism and mimicry Curious Dogs -Symptoms: foaming mouths, shaking, vomiting, diarrhea Derived from: -Diet -Alkaloid manufacture Diet (ants, athropods) Poisonous frogs tend to advertise their toxicity with bright colours, an adaptive strategy known as aposematism. There are at least two non-poisonous species of frogs in tropical America (Eleutherodactylus gaigei and Lithodytes lineatus) that mimic the colouration of dart poison frogs' coloration for self-protection (Batesian mimicry).[10][11] http://www.gilroydispatch.com

Handling-PE Before handling, observe the amphibian’s body condition and color, posture, skin condition, movement and activity level, respiratory effort, and response to stimuli. A brief but thorough examination of the eyes, nares, and conjunctiva is easily made using an ophthalmoscope or slit lamp. The oral cavity, including the back of the soft palate where only a thin layer of tissue separates the buccal cavity from the eye, can be observed after opening the mouth with a thin piece of waterproof paper or plastic card. An accurate weight can be determined with minimal handling. It is essential for dosing but tends to be variable depending on hydration, feeding, and urine volume

Amphibians These animals have a very delicate and sensitive epidermis and mucous covering skin. Handle only if needed and use wet hands. Picture to right is how most toads are handled

Frogs However, it’s not as easy as it looks, Frogs are extremely slippery. Larger frogs may be held by the back legs if the body is supported.

Handling-Restraint Caudata Goals: -Support and comfort -Netting -MS-222 -Avoid tail and gills http://aqualandpetsplus.com/Amphibian,%20Salamander.htm

Handling-Restraint Anura Goals: -Support and comfort -Netting -MS-222 -Avoid kicking out African clawed toads - sharp claws, be careful www.uwm.edu/Dept/EHSRM/ACP/MANUAL/Frog2.jpg

Chemical Restraint of Amphibians General anesthesia may be required to obtain a blood sample or for surgical procedures such as fracture repair or laparoscopic or exploratory surgery. Anesthesia can be achieved by using a bath of tricaine methanesulfonate (MS-222, Argent Chemical Laboratories, Redmond, WA USA). 2 g of MS-222, 40 mL of 0.5 mol/L Na2HPO4, and 2L of well-oxygenated enclosure water. This produces a 1 g/L (0.1%) solution, which is often suitable for adult aquatic amphibians. Induction of adult terrestrial species may require up to 3 g/L.5 larvae and some small adult amphibians can often be anesthetized with as little as 0.2 g/L

Isoflurane/Lube/H2O Page 232 3.0 ml liquid Isoflurane 1.5 ml water 3.5 ml KY Jelly Mix everything in a 10 ml syringe and shaken The resulting liquid is then applied on the back of the patient at a dose of 0.025 ml to 0.035 ml/g of body weight

Sleeping toad

Venipuncture on Frogs and Toads There is a sub-Q space for injections over entire dorsal and ventral aspect. Unless animal is large enough to have visible veins, blood is collected from the heart. The sternum is pushed to one side and blood is collected with a 22-26 g needle. Never use alcohol for disinfecting the site of the venipuncture. Use diluted 2% chloroxylenol Location for venipuncture performance, read page 234-235

Abdominal vein

Femoral vein

Sub-Lingual vein

Medication bath (TO)