Digestive Anatomy of the Dingo
The understanding of digestion in the dingo is inferred largely from studies of wolves and domestic dogs. Since the majority of the canine is highly digestible, it requires only a short gut like most carnivores.
The strong jaw and large canines permit the dingo to procure and machinate rather tough prey, allowing them to tear meat from carcasses and crush bones to obtain calcium and fat. Since the dingo is a carnivore, unlike a herbivore it is unable to perform sideways jaw movement because it does not ruminate. Canine saliva also does not contain enzymes, rather its role is to lubricate large procurements of food to aid swallowing.
Salivation is prompted immediately in the dingo by the sight and smell of prey even before procurement, known as the famous Pavlovian response. As food is procured, salivation increases and stimulates the taste buds. According to Mech and Boitani (2003), “the most potent compounds for stimulating the taste buds in…wolves are amino acids that taste sweet to humans, especially L-cysteine, L-proine, L-lysine, and L-leucine…taste buds respond to nucleotides, and their constituent amino acids probably help distinguish among meats of various nutritional qualities.
The saliva is produced in the orbital, parotid, mandibular, and sublingual glands and is slightly acidic and lubricating to ensure maximum intake and “minimum loss to scavengers and fellow pack members” (2003). There is not much mechanical digestion in the mouth aside from the chewing of hide and bone.
The stomach is large and muscular, allowing it to eat more food in a smaller period of time in order to sustain itself for longer. The esophagus hosts no enzymes but adds mucus as food approaches the stomach, which adds even more mucus and uses hydrochloric acid and proteases such as pepsin to digest proteins. In the distal area of the stomach, alkaline fluids low in enzymes are produced which mix with the stomach contents to neutralize the acids and produce chyme, which then flows into the small intestine.
The flow of chyme through the pyloric sphincter into the small intestine is slowed by the presence of acids, irritants, fats or chyme in the anterior region of the small intestine.
Unlike herbivores, it is in the small intestine where most nutrient uptake occurs. The gall bladder and pancreas secrete digestive enzymes (protease for protein, lipase and bile for lipids, and amylase for carbohydrates) as well as bicarbonate salts to neutralize the chyme once more. The canine pancreas is small comparatively to a large mammals, and has a smaller proportion of enzymes than a human would. Thus, the canine requires prey items that contain enzymes to digest the food for absorption.
The canine intestine is shorter than a herbivores because there is faster absorption and rates of elimination into waste products. As well, this carnivore is adapted to absorb large water quantities from its prey so it requires less frequent visits to a water source.
In the large intestine, the final sight of digestion, the canine absorbs some water and electrolytes while overseeing the bacterial catabolism of protein and fibre residue into feces. The time for total digestion is wholly dependent on what prey was ingested, thus varying greatly. However, wolves usually pass food at a rate of 12 hours, with 8 hours as the minimum time from food to feces, and 48 hours to clear all the system of all scat from a particular feeding.
Reference for this page:
Mech, L. David., and Luigi Boitani. Wolves: Behavior, Ecology, and Conservation. Chicago: U of Chicago, 2003. Print.