Amphibians & Reptiles


Dog's Digestive System
Bearded dragons eat waxworms and butterworms eagerly, but the worms should not make up a substantial percentage of the lizard's diet due to their higher fat content. Jomahna, If you are nervous about feeding raw dog food then just feed him cooked. Rattlesnakes rapidly vibrate the tip of the tail, which is composed of a series of nested, hollow beads to ward of approaching danger. In pit vipers, the grooves are located between the nostril and the eye in a large "pit" on each side of the head. It is often also distinctly discolored compared to the rest of the body and may lack some of the external sculpting features seen in the original tail. Fossils found in Nova Scotia show footprints with imprints of scales and typical reptilian toes.

What Is a Reptile?

Reptile Care

These can be mounted as a basking lamp. They are fine for many lizards, but for lizards that require natural sunlight, it is not adequate. These must have fluorescent lighting. Fluorescent bulbs A full-spectrum fluorescent bulb provides a sunlight replacement for those pets that need full-spectrum lighting. Not all require this, but those that do will be at risk if they don't get it.

These include many diurnal, or day-time active lizards and tortoises. Of course, natural sunlight is the best source of full-spectrum lighting.

Flooring Covering There are a variety of floor coverings that can be used for your pet, but they all have their own considerations.

One of the primary considerations in choosing floor coverings is cleanliness. Be wary of harmful micro-organisms. Reptile cage carpets Reptile cage carpets are often an ideal floor covering. They are made for your pet, not for human floors, so they are not abrasive to your pets skin. They are also easy to remove and clean. Household carpets are not made for reptiles, they are chemically treated and are designed for abrasion. Reptile sand Sand is sometimes used, but it tends to cling to herptiles feet and to get into their food.

It can be very harmful if it is ingested. Gravel is a better choice, but should be washed and disinfected. There is a calcium sand available that is said to be digestible, however is should be used with caution as impaction problems have been said to occur with some herps. Other substrates Other options are shredded barks and packaged peat mosses, but be mindful of cleanliness.

Cage Decor Cage decor is very important for your pet. It provides their sense of security through shelters and camouflaging. It also includes maintenance things, like food and water dishes and heating devices. Some standard decor items are rocks, basking limbs and plants. Wash everything you put in. Sand or logs that you collect from outside needs to be cleaned and bleached or sterilized in a slow oven degrees to degrees for two to three hours.

Wood limbs and rocks are very natural additions, but make sure they don't have any sharp parts that can injure your pet.

Limbs can be sealed with polyurethane varnish to prevent places for parasites to live. These can be used in dry land or aquatic terrariums. Aquarium plants, such as elodea anacharis , can do well in aquatic terrariums. Herptile Cage Care Cage maintenance is an important part of keeping reptiles and amphibians healthy, and long-lived. With most herptiles being kept in a confined area as pets, they need to be protected from harmful micro-organisms and parasites.

The reptile cage also needs daily and weekly maintenance. Things you will need to do for your herps home include:. Herptile Diet Types and Foods Whether you are keeping reptiles or amphibians, the diet varies with each animal. Yet each herptile has primarily one of three types of diets. Some herps are carnivores - a meat or protein eater, others are herbivores - a plant eater or omnivores - which are animals that eat both plants and proteins.

Carnivores Herptiles that are carnivores eat proteins such as rodents, insects and invertebrates. Other proteins include guppies, goldfish, eggs, and some birds.

Some even eat other herptiles, for example a snake will eat a frog and a large lizard will eat a small lizard. Some of the rodents herps will eat include mice, rats, pinkies and fuzzies terms for baby and juvenile mice and rats , rabbits and chickens. These proteins form the basis of many snakes and some lizards diets. They can be fed live or purchased frozen and completely defrosted before feeding. Be cautious when feeding live adult rats.

Snakes that do not feed immediately on an adult rat run the risk of being bitten by a loose rat, and can be severely damaged. Reptile foods for carnivores include: Crickets The most currently fed insects include crickets, which can be purchased in a variety of sizes to fit the herptile you are feeding. Mealworms Another is mealworms. These are not really worms, but the larval state of the flour beetle. They are low in calcium, and so should be coated with a calcium supplement.

Flies Flies can be purchased as larva. Worms Waxworms, butterworms, red worms, earthworms, and night crawlers also make good protein choices. Tiny proteins Fruitflies, blackworms, bloodworms and tubifex worms are very tiny, so can be fed to aquatic frogs, toads and baby turtles Herbivores Herbivores tend to need large amounts of food and a good variety.

Commercially prepared complete diets are available for iguanas, turtles and tortoises and should contain the necessary vitamins and minerals. Otherwise feed fresh foods with a vitamin and mineral supplement. Especially feed those foods high in fiber. Spinach should not be fed as it binds up calcium internally, and renders it ineffective. Reptile foods for herbivores include: Do not feed tomatoes to iguanas!

Omnivores There probably are some vegetarian type herps that are truly omnivores throughout their lives, but most adult herbivores are true vegetarians.

Reptiles that are true herbivores as adults include Iguanas and several of the large tortoises such as the Sulcata or African Spurred Tortoise Geochelone sulcata. In captivity they may erroneously be offered a variety of items such as insects and cat food that are not natural in the wild diet.

Many iguanas suffer early death because of this. I would appreciate any comment, as I am very concerned about my Grace. Hi — Thank you very much for your informative website. My husband and I own an 8. He has always been very healthy. I changed him to a home cooked diet of cooked chicken breast; brown rice and sweet potato. He loves the food; but was losing a lot of weight. I found your website about 2 weeks ago and substituted the rice for white potato in addition to adding hard boiled eggs.

He is currently on Omega supplements; however his Vet recommended to supplement safflower oil for fat — I see that you recommend extra virgin coconut oil.

Although his weight is still in the healthy range; he has gone from 75 lbs to 65 lbs in the past 3 months since the diet change. His recent bloodwork is excellent and energy level is good — I just feel like he is very thin. I am concerned about giving him the right fats. Try adding the Supromega fish oil or Lickochops , both are great fat sources. Virgin coconut oil also does not stress the pancreas. Dear Ed what do you reccomend for a dog who has a high ph of 6 and is not producing enough acid on her own to keep from getting sturitve stones and is getting constant bladder infections she has gone through surgery to remove the stones and is a special deit of royal canin urinary so wet and dry and for six months was given a clean bill of health by her vet but now she has and infection again and crystals im being told by her vet that its time to possibles start her on a monthy antiboitic treat meant to hopefully get her system back on track which im really concerned about.

Neither have any known health problems and no skin issues. Can I start her on the raw diet right after that? Yes, cats can eat a raw diet safely just eliminate all the carbs because they have no use for them at all.

I started him on a grain free kibble and mixed in raw meat with his food , enzymes a other supplements and for 4 years he has been fine. I do know that kibble and raw digest at different rate. I give him beef heart, tongue and liver. He has recovered nicely and became my service dog now at 9 I am training another and he is now in semi retirement he will never fully retire until he passes on.

Lately he has not been very good at eating his meals oh he is feed twice a day half in the a. GSD are prone to bloat. He will eat if I give him some of what I am eating and he will eat the raw meat alone so my question what to do about feeding a raw diet. I have 4 dogs and with the constant increase in meat prices it is hard to put all on a raw only diet. When you feed a raw meat and bones based diet bloat is not a problem. This is because the raw maenad bonds not swell like kibble.

Currently I am feeding my dogs raw chicken leg and thigh quarters. I grind them using the meat grinder I show on this site because both my dogs are missing teeth.

The chicken is 69 cents per pound. You must be logged in to post a comment. My name is Ed Lukacevic and I'm an incurable animal lover! I have spent my life working with birds, reptiles, horses and especially dogs.

Optimum nutrition for the animals in my care has been my passion. March 19, at 9: What about corn on the cob? Log in to Reply. Darcy, Can you tell me what you are feeding your dog?

April 1, at 4: April 2, at 8: Marie, Dogs can eat the vegetables but not digest them well. May 27, at 8: May 29, at 3: Christa, You may want to try the yeast starvation dog food recipe.

February 4, at 9: February 5, at Natasha, Try feeding the chicken and rice dog food recipe , substitute sweet potato for the white rice. July 4, at 1: July 5, at 4: Chris, Are you feeding the easy cooked dog food recipe? July 5, at 6: July 16, at 4: Chris, Just keep it up and see how she does. I forgot to mention that we also give her krill oil supplements as well.

July 28, at 4: July 31, at 1: August 5, at 7: August 5, at 8: Carolyn, Sounds like a good idea but brace yourself for negative feedback. September 5, at 1: July 30, at Grace, Dogs are easy vomiters. What is she eating now? August 22, at August 18, at 4: August 21, at 7: Linda, Switching between homemade dog food recipes does not require a fast. September 20, at 4: Jill, You may want to try the chicken and rice dog food recipe. August 28, at September 3, at 8: September 4, at 5: September 10, at Jomahna, If you are nervous about feeding raw dog food then just feed him cooked.

September 6, at 9: September 29, at 1: October 2, at 8: October 4, at October 6, at 9: Gail, Try the easy cooked dog food recipe or the chicken and rice dog food recipe and see how she does. January 4, at 9: January 5, at 8: February 16, at 8: Sorry, I forgot this question, is cooked beef hard on a dogs digestive system? February 17, at 8: March 28, at 2: My dog ate glass. March 28, at 9: Lacey, You may want to have your dog checked out by a veterinarian.

May 6, at Thank you again for this wonderful website — many blessings. May 7, at 3: Some species retain a pelvic girdle with a pair of vestigial claws on either side of the cloaca. Lizards have evolved elongate bodies without limbs or with greatly reduced limbs about twenty five times independently via convergent evolution , leading to many lineages of legless lizards. Living snakes are found on every continent except Antarctica, and on most smaller land masses; exceptions include some large islands, such as Ireland, Iceland, Greenland, the Hawaiian archipelago , and the islands of New Zealand, and many small islands of the Atlantic and central Pacific oceans.

More than 20 families are currently recognized, comprising about genera and about 3, species. The oldest preserved descriptions of snakes can be found in the Brooklyn Papyrus. Most species are nonvenomous and those that have venom use it primarily to kill and subdue prey rather than for self-defense. Some possess venom potent enough to cause painful injury or death to humans.

Nonvenomous snakes either swallow prey alive or kill by constriction. The fossil record of snakes is relatively poor because snake skeletons are typically small and fragile making fossilization uncommon. Fossils readily identifiable as snakes though often retaining hind limbs first appear in the fossil record during the Cretaceous period.

Based on comparative anatomy , there is consensus that snakes descended from lizards. Front limbs are nonexistent in all known snakes. This is caused by the evolution of their Hox genes , controlling limb morphogenesis.

Early in snake evolution, the Hox gene expression in the axial skeleton responsible for the development of the thorax became dominant.

As a result, the vertebrae anterior to the hindlimb buds when present all have the same thoracic-like identity except from the atlas , axis , and 1—3 neck vertebrae.

In other words, most of a snake's skeleton is an extremely extended thorax. Ribs are found exclusively on the thoracic vertebrae. Neck, lumbar and pelvic vertebrae are very reduced in number only 2—10 lumbar and pelvic vertebrae are present , while only a short tail remains of the caudal vertebrae. However, the tail is still long enough to be of important use in many species, and is modified in some aquatic and tree-dwelling species.

Many modern snake groups originated during the Paleocene , alongside the adaptive radiation of mammals following the extinction of non-avian dinosaurs. The expansion of grasslands in North America also led to an explosive radiation among snakes.

There is fossil evidence to suggest that snakes may have evolved from burrowing lizards, such as the varanids or a similar group during the Cretaceous Period. These include fossil species like Haasiophis , Pachyrhachis and Eupodophis , which are slightly older than Najash. This hypothesis was strengthened in by the discovery of a m year-old fossil of a four-legged snake in Brazil that has been named Tetrapodophis amplectus. It has many snake-like features, is adapted for burrowing and its stomach indicates that it was preying on other animals.

Tetrapodophis does not have distinctive snake features in its spine and skull. An alternative hypothesis, based on morphology , suggests the ancestors of snakes were related to mosasaurs —extinct aquatic reptiles from the Cretaceous —which in turn are thought to have derived from varanid lizards. This ultimately led to an animal similar to today's sea snakes. In the Late Cretaceous , snakes recolonized land, and continued to diversify into today's snakes.

Fossilized snake remains are known from early Late Cretaceous marine sediments, which is consistent with this hypothesis; particularly so, as they are older than the terrestrial Najash rionegrina. Similar skull structure, reduced or absent limbs, and other anatomical features found in both mosasaurs and snakes lead to a positive cladistical correlation, although some of these features are shared with varanids. Genetic studies in recent years have indicated snakes are not as closely related to monitor lizards as was once believed—and therefore not to mosasaurs, the proposed ancestor in the aquatic scenario of their evolution.

However, more evidence links mosasaurs to snakes than to varanids. Fragmented remains found from the Jurassic and Early Cretaceous indicate deeper fossil records for these groups, which may potentially refute either hypothesis.

In two studies reported that limb loss in snakes is associated with DNA mutations in the Zone of Polarizing Activity Regulatory Sequence ZRS , a regulatory region of the sonic hedgehog gene which is critically required for limb development. More advanced snakes have no remnants of limbs, but basal snakes such as pythons and boas do have traces of highly reduced, vestigial hind limbs. Python embryos even have fully developed hind limb buds, but their later development is stopped by the DNA mutations in the ZRS.

There are over 2, species of snakes ranging as far northward as the Arctic Circle in Scandinavia and southward through Australia. All modern snakes are grouped within the suborder Serpentes in Linnean taxonomy , part of the order Squamata , though their precise placement within squamates remains controversial. The two infraorders of Serpentes are: Alethinophidia is sometimes split into Henophidia and Caenophidia , with the latter consisting of "colubroid" snakes colubrids , vipers , elapids , hydrophiids , and atractaspids and acrochordids, while the other alethinophidian families comprise Henophidia.

There are numerous debates in the systematics within the group. For instance, many sources classify Boidae and Pythonidae as one family, while some keep the Elapidae and Hydrophiidae sea snakes separate for practical reasons despite their extremely close relation.

While snakes are limbless reptiles, which evolved from and are grouped with lizards, there are many other species of lizards which have lost their limbs independently and superficially look similar to snakes. These include the slowworm and glass snake.

The now extinct Titanoboa cerrejonensis snakes found were At the other end of the scale, the smallest extant snake is Leptotyphlops carlae , with a length of about Pit vipers, pythons, and some boas have infrared-sensitive receptors in deep grooves on the snout, which allow them to "see" the radiated heat of warm-blooded prey.

In pit vipers, the grooves are located between the nostril and the eye in a large "pit" on each side of the head. Other infrared-sensitive snakes have multiple, smaller labial pits lining the upper lip, just below the nostrils. Snakes use smell to track their prey. They smell by using their forked tongues to collect airborne particles, then passing them to the vomeronasal organ or Jacobson's organ in the mouth for examination.

In water-dwelling snakes, such as the anaconda , the tongue functions efficiently underwater. The underside is very sensitive to vibration. This allows snakes to be able to sense approaching animals by detecting faint vibrations in the ground. Snake vision varies greatly, from only being able to distinguish light from dark to keen eyesight, but the main trend is that their vision is adequate although not sharp, and allows them to track movements.

Some snakes, such as the Asian vine snake genus Ahaetulla , have binocular vision , with both eyes capable of focusing on the same point. Most snakes focus by moving the lens back and forth in relation to the retina , while in the other amniote groups, the lens is stretched. Many nocturnal snakes have slit pupils while diurnal snakes have round pupils. The skin of a snake is covered in scales. Contrary to the popular notion of snakes being slimy because of possible confusion of snakes with worms , snakeskin has a smooth, dry texture.

Most snakes use specialized belly scales to travel, gripping surfaces. The body scales may be smooth, keeled , or granular. The eyelids of a snake are transparent "spectacle" scales, which remain permanently closed, also known as brille. The shedding of scales is called ecdysis or in normal usage, molting or sloughing. In the case of snakes, the complete outer layer of skin is shed in one layer.

Snakes have a wide diversity of skin coloration patterns. These patterns are often related to behavior, such as a tendency to have to flee from predators. Snakes that are plain or have longitudinal stripes often have to escape from predators, with the pattern or lack thereof not providing reference points to predators, thus allowing the snake to escape without being notice.

Plain snakes usually adopt active hunting strategies, as their pattern allows them to send little information to prey about motion. Blotched snakes, on the other hand, usually use ambush-based strategies, likely because it helps them blend into an environment with irregularly shaped objects, like sticks or rocks. Spotted patterning can similarly help snakes to blend into their environment.

The shape and number of scales on the head, back, and belly are often characteristic and used for taxonomic purposes. Scales are named mainly according to their positions on the body. In "advanced" Caenophidian snakes, the broad belly scales and rows of dorsal scales correspond to the vertebrae , allowing scientists to count the vertebrae without dissection. Molting , or ecdysis , serves a number of functions. Firstly, the old and worn skin is replaced; secondly, it helps get rid of parasites such as mites and ticks.

Renewal of the skin by molting is supposed to allow growth in some animals such as insects; however, this has been disputed in the case of snakes. Molting occurs periodically throughout the snake's life. Before a molt, the snake stops eating and often hides or moves to a safe place. Just before shedding, the skin becomes dull and dry looking and the eyes become cloudy or blue-colored. The inner surface of the old skin liquefies.

This causes the old skin to separate from the new skin beneath it. After a few days, the eyes clear and the snake "crawls" out of its old skin. The old skin breaks near the mouth and the snake wriggles out, aided by rubbing against rough surfaces. In many cases, the cast skin peels backward over the body from head to tail in one piece, like pulling a sock off inside-out.

A new, larger, brighter layer of skin has formed underneath. An older snake may shed its skin only once or twice a year. But a younger snake, still growing, may shed up to four times a year. Scale counts can sometimes be used to tell the sex of a snake when the species is not distinctly sexually dimorphic. A probe is inserted into the cloaca until it can go no further. The probe is marked at the point where it stops, removed, and compared to the subcaudal depth by laying it alongside the scales.

The skeleton of most snakes consists solely of the skull, hyoid, vertebral column, and ribs, though henophidian snakes retain vestiges of the pelvis and rear limbs.

The skull of the snake consists of a solid and complete neurocranium , to which many of the other bones are only loosely attached, particularly the highly mobile jaw bones, which facilitate manipulation and ingestion of large prey items. The left and right sides of the lower jaw are joined only by a flexible ligament at the anterior tips, allowing them to separate widely, while the posterior end of the lower jaw bones articulate with a quadrate bone, allowing further mobility.

The bones of the mandible and quadrate bones can also pick up ground borne vibrations. The jaw-quadrate-stapes pathway is capable of detecting vibrations on the angstrom scale, despite the absence of an outer ear and the ossicle mechanism of impedance matching used in other vertebrates to receive vibrations from the air. The hyoid is a small bone located posterior and ventral to the skull, in the 'neck' region, which serves as an attachment for muscles of the snake's tongue, as it does in all other tetrapods.

The vertebral column consists of anywhere between and or more vertebrae. The vertebrae have projections that allow for strong muscle attachment enabling locomotion without limbs. Autotomy of the tail, a feature found in some lizards is absent in most snakes. In some snakes, most notably boas and pythons , there are vestiges of the hindlimbs in the form of a pair of pelvic spurs.

These small, claw-like protrusions on each side of the cloaca are the external portion of the vestigial hindlimb skeleton, which includes the remains of an ilium and femur. Snakes are polyphyodonts with teeth that are continuously replaced. The snake's heart is encased in a sac, called the pericardium , located at the bifurcation of the bronchi. The heart is able to move around, however, owing to the lack of a diaphragm. This adjustment protects the heart from potential damage when large ingested prey is passed through the esophagus.

The spleen is attached to the gall bladder and pancreas and filters the blood. The thymus is located in fatty tissue above the heart and is responsible for the generation of immune cells in the blood.

The cardiovascular system of snakes is also unique for the presence of a renal portal system in which the blood from the snake's tail passes through the kidneys before returning to the heart. The vestigial left lung is often small or sometimes even absent, as snakes' tubular bodies require all of their organs to be long and thin. This lung contains a vascularized anterior portion and a posterior portion that does not function in gas exchange.

Snakes have no lymph nodes. Cobras, vipers, and closely related species use venom to immobilize or kill their prey. The venom is modified saliva , delivered through fangs. Snake venoms are often prey specific—their role in self-defense is secondary. Venom, like all salivary secretions, is a predigestant that initiates the breakdown of food into soluble compounds, facilitating proper digestion.

Even nonvenomous snake bites like any animal bite will cause tissue damage. Certain birds, mammals, and other snakes such as kingsnakes that prey on venomous snakes have developed resistance and even immunity to certain venoms. The colloquial term "poisonous snake" is generally an incorrect label for snakes.

A poison is inhaled or ingested, whereas venom produced by snakes is injected into its victim via fangs. Rhabdophis sequesters toxins from the toads it eats, then secretes them from nuchal glands to ward off predators, and a small unusual population of garter snakes in the U.

Snake venoms are complex mixtures of proteins , and are stored in venom glands at the back of the head. Venomous snakes that use hemotoxins usually have fangs in the front of their mouths, making it easier for them to inject the venom into their victims. They must actually bite the victim. It has recently been suggested that all snakes may be venomous to a certain degree, with harmless snakes having weak venom and no fangs.

This theory postulates that snakes may have evolved from a common lizard ancestor that was venomous—and that venomous lizards like the gila monster , beaded lizard , monitor lizards , and the now-extinct mosasaurs may also have derived from it. They share this venom clade with various other saurian species.

Venomous snakes are classified in two taxonomic families:. There is a third family containing the opistoglyphous rear-fanged snakes as well as the majority of other snake species:. Although a wide range of reproductive modes are used by snakes, all snakes employ internal fertilization. This is accomplished by means of paired, forked hemipenes , which are stored, inverted, in the male's tail.

Bearded Dragon Diets and Food Items Explained