Impala kill in South Africa
Digestive System
It's truly fascinating how cheetahs thrive under a habitat that demands so much; the first one being origin/geographically located in Africa where water is scarce. Because cheetahs are able to thrive under such conditions in Africa where droughts often occur and them being able to survive days without water, natural selection will automatically favor cheetahs rather than an animal that's so dependent on water consumption. In Animal Physiology by Richard W. Hill et al., it elaborates that carnivorous mammals such as cheetahs are generally assumed to achieve water balance without having to drink much (if at all) because of the high water content of their foods.
In Johnston (2018), it was mentioned that "the main prey species of cheetahs include impala, blesbok, kudu, steenbok, duiker, Thomson's gazelle, springbok, and hartebeest" to only name a few. In the video and picture above, you can witness how this female cheetah manages to take down an impala. Because cheetahs are not built for fighting, "cheetahs are likely to prey on animals that are similar to their size or smaller in order to reduce the chance of kleptoparasitism," (Johnston., 2018). The reduction of preferred prey in a certain area can lead to the decline of cheetah in that region (Howard et al. 2006).
Cheetahs are felines and because they are felines, they have well-advanced non-gustatory papillae on the back surface of their tongues. Cheetah's tongue is specifically shaped and texturized the way they are in order to separate meat from the bone when consuming prey. Carnivores esophagus contains striated muscle which expands to their stomach making it viable for them to regurgitate without any trouble (Ewer, 1973). Cheetah's cheek teeth
happen to be extremely narrow and conjointed with the small roots that are not able of dealing with big bones (Leemans 2014). Cheetahs have a simple stomach in which it contains a predominant small intestine tract and a reduced large intestinal tract with a reduction in the distinction between colon and rectum (Leemans 2014). Cheetahs have a somewhat tiny colon, its proportion is about 20% of the entire span of their digestive tract (Ewer, 1973). The majority of the parts are absorbed by the small intestine. In the small intestine walls, the villi do the job of enlarging their surface in order to boost absorption. The duodenum is usually the mixing site and the absorption mostly occurs in the jejunum (Leemans 2014). "Monosaccharides, amino acids, and peptides are actively absorbed. Carrier proteins transfer these nutrients across the intestinal wall," (Leemans 2014). Lipids get absorbed through passive diffusion after micelle formation. Short-chain fatty acids get absorbed into the bloodstream devoid of bile salts. Minerals along with vitamins that are water-soluble get absorbed through diffusion and carrier-mediated transport (Leemans 2014). Vitamins including A, D, E, and K that are fat-soluble get shifted along the brush border passively. When their food is being digested in the stomach, it has a higher O2 content and proceeds very quickly in the proximal segment of the digestive tract. When the food then reaches the large intestine, O2 is no longer there and the microbe begins fermentation.
Cheetahs are in the order of Carnivora and are classified in the Felidae family which means that they strickly rely on meat consumption. Furthermore, cheetahs have 2 essential nutrients that are not essential in any other mammalian family which are taurine and arginine. "Taurine is one of the most abundant amino acids in the vertebrate CNS," (Markwell et al, 1994). The enzyme that initiates the breaking down
process of "taurine from cysteinesulphinic acid are available but the movement of the enzymes are relatively low," (knopf et al, 1978). Arginine is broken down from citrulline due to the subsequent movement of enzymes. Although cheetahs diet consists mostly protein-based, they are still able to take in carbohydrates like glucose, lactose, starch, etc... Due to them not actively breaking down sugar often, it led to them obtaining a reduced activity of intestinal disaccharidases that synthesizes carbohydrates in the intestines, (Zoran, 2002). Although the cheetah’s enzymes might be different when comparing to other mammals, it doesn't necessarily mean that they are "unhealthy" or deficient in terms of enzymes. In fact, all of the essential nutritional compounds are there and are sufficient, in quantities and so therefore, cheetahs are able to thrive and adapt under the environment that they are in.
