In this portion of my bog, I will be discussing the digestive tract and general physiology of the fox. Since the red fox and the fennec fox are essentially the same species, there will only be one blog post for this topic. Their anatomy does not differ very much. A reference diagram of a fox gastrointestinal tract could not be found from a credible source (journal). Therefore, a closely related relative’s was used as a substitute.
The digestive tract or sometimes referred to as the gastrointestinal tract (GIT), contains all organs necessary to obtain and process food materials[1]. The red fox and fennec are both omnivores, however their digestive system is closely related to their carnivore cousin, dogs[1]. The digestive system starts with the mouth, where food intake occurs and mechanical digestion takes place[2]. Food matter is chewed and broken down with the help of the enzyme amylase, which catalyses the hydrolysis of starch[2]. Afterwards, chewed food known as the bolus travels down the esophagus and into the stomach[2]. Once food is inside the stomach, more mechanical and chemical digestion occurs[2]. Tough muscular walls will aid in mechanical breakdown of the bolus[2]. The enzyme Gastrin is released, stimulates the secretion of HCl and intrinsic factor[2]. HCl helps to break down proteins by converting pepsinogen to pepsin and to keep the stomach at a low pH 1.5-3.8[2]. Pepsin cause conversion of proteins into polypeptides that travel down into the small intestine for further breakdown[2]. The small intestine consists of three sections: duodenum, jejunum and ilium[2]. Most of digestion and absorption will occur in duodenum[2]. Bile, produced in liver, secreted into small intestine to help fat digestion and breakdown, as well as to emulsify any toxins[2]. Carbohydrates will be digested further by pancreatic amylase secreted by the pancreas, also helps to breakdown starch[2]. Disaccharide sugars will be broken down into monosaccharide sugars to be easily absorbed by cells[2]. The small intestine also has a higher pH than the stomach, ranging from 5-7[2]. Food will travel past the cecum, a small organ at the end of the small intestine[2]. Fluids and salts that were not digested before are mixed with mucus and travel down into the large intestine[2]. This is where plant material is broken down by bacteria via fermentation[2]. Although it should be noted that carnivores and omnivores are largely incapable of digesting any plant matter[2]. Finally, food waste is process and excreted via the anus[2].
There is no real physiological difference on the inside of the two fox species[3]. Except for the size difference between them, the fennec’s organs and GIT will be smaller comparatively[3]. Also note, the fennec has much larger ears than any other fox[4]. This mechanism is a tracking mechanism, fennecs typically have poor eyesight[4]. The larger earls also help to dissipate heat because many of its blood vessels are located near the surface[4].
References:
1. Lanszki, J., heltai, M., 2002. Feeding habits of golden jackal and red fox in South-western Hungary During winter and spring. Mamm. Biol. 67, 129-136.
2. Chan, A., Horn, M., Dickson, K., Gawlicka, A., 2004. Digestive enzyme activities in carnivores and herbivores: comparisons among four closely related prickleback fishes from a California rocky internal habitat. J. Fish. Biol. 65, 848-858.
3. Dampsey, J., Hanna, S., Asa, C., Bauman, K., 2009. Nutrition and Behavior of Fennec Foxes (Vulpes zerda). Vet. Clin. Exot. Anim. 12, 299-312.
4. Dampsey, J., Hanna, S., Asa, C., Bauman, K., 2009. Nutrition and Behavior of Fennec Foxes (Vulpes zerda). Vet. Clin. Exot. Anim. 12, 299-312.
The digestive tract or sometimes referred to as the gastrointestinal tract (GIT), contains all organs necessary to obtain and process food materials[1]. The red fox and fennec are both omnivores, however their digestive system is closely related to their carnivore cousin, dogs[1]. The digestive system starts with the mouth, where food intake occurs and mechanical digestion takes place[2]. Food matter is chewed and broken down with the help of the enzyme amylase, which catalyses the hydrolysis of starch[2]. Afterwards, chewed food known as the bolus travels down the esophagus and into the stomach[2]. Once food is inside the stomach, more mechanical and chemical digestion occurs[2]. Tough muscular walls will aid in mechanical breakdown of the bolus[2]. The enzyme Gastrin is released, stimulates the secretion of HCl and intrinsic factor[2]. HCl helps to break down proteins by converting pepsinogen to pepsin and to keep the stomach at a low pH 1.5-3.8[2]. Pepsin cause conversion of proteins into polypeptides that travel down into the small intestine for further breakdown[2]. The small intestine consists of three sections: duodenum, jejunum and ilium[2]. Most of digestion and absorption will occur in duodenum[2]. Bile, produced in liver, secreted into small intestine to help fat digestion and breakdown, as well as to emulsify any toxins[2]. Carbohydrates will be digested further by pancreatic amylase secreted by the pancreas, also helps to breakdown starch[2]. Disaccharide sugars will be broken down into monosaccharide sugars to be easily absorbed by cells[2]. The small intestine also has a higher pH than the stomach, ranging from 5-7[2]. Food will travel past the cecum, a small organ at the end of the small intestine[2]. Fluids and salts that were not digested before are mixed with mucus and travel down into the large intestine[2]. This is where plant material is broken down by bacteria via fermentation[2]. Although it should be noted that carnivores and omnivores are largely incapable of digesting any plant matter[2]. Finally, food waste is process and excreted via the anus[2].
There is no real physiological difference on the inside of the two fox species[3]. Except for the size difference between them, the fennec’s organs and GIT will be smaller comparatively[3]. Also note, the fennec has much larger ears than any other fox[4]. This mechanism is a tracking mechanism, fennecs typically have poor eyesight[4]. The larger earls also help to dissipate heat because many of its blood vessels are located near the surface[4].
References:
1. Lanszki, J., heltai, M., 2002. Feeding habits of golden jackal and red fox in South-western Hungary During winter and spring. Mamm. Biol. 67, 129-136.
2. Chan, A., Horn, M., Dickson, K., Gawlicka, A., 2004. Digestive enzyme activities in carnivores and herbivores: comparisons among four closely related prickleback fishes from a California rocky internal habitat. J. Fish. Biol. 65, 848-858.
3. Dampsey, J., Hanna, S., Asa, C., Bauman, K., 2009. Nutrition and Behavior of Fennec Foxes (Vulpes zerda). Vet. Clin. Exot. Anim. 12, 299-312.
4. Dampsey, J., Hanna, S., Asa, C., Bauman, K., 2009. Nutrition and Behavior of Fennec Foxes (Vulpes zerda). Vet. Clin. Exot. Anim. 12, 299-312.