Summary
Morphologically the large intestine of the nutria resembles that of other caviomorphs, notably the guinea pig. The cecum is voluminous: it contributes 8.6% of the total intestinal length and 12.7% of the total intestinal surface area (considering the surface enlargement factor). It contains 27–32% of the wet ingesta and 20–23% of the dry matter in the gastrointestinal tract. In the colon the corresponding figures are: 21.8% of length, 12.6% of surface area, 16–21% of wet ingesta, and 16–40% of dry matter. The colon can be subdivided both structurally and functionally into two sections, the proximal and the distal colon, the border between the two being the apical flexure of a long parallel loop. The proximal colon (42% of colonic length) displays on the mucosal surface of its mesenterial side a narrow furrow bordered by ridges, which is absent in the distal colon. The ridges contain subepithelial accumulations of coiled tubuloalveolar mucoid glands, entwined by bundles of muscle fibers. Determinations of nitrogen in the contents near the furrow suggest a concentration of bacteria in this part of the lumen. It is hypothesized that the structural differentiations of the proximal colon provide mechanisms for the transport of bacteria from the proximal colon back into the cecum to maintain the fermentation function. The slopes of the longitudinal profiles for dry matter and for concentrations of sodium, potassium and calcium in the luminal contents change at the tip of the parallel loop. The electrical potential difference “intestinal lumen — blood” is particularly large in the proximal colon, indicating active electrogenic ion transport in this region.
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Abbreviations
- SEF :
-
surface enlargement factor
- CSM :
-
colonic separation mechanism
- PEG :
-
polyethylene glycol
- DM :
-
dry matter
References
Alexander F (1962) The concentration of certain electrolytes in the digestive tract of the horse and the pig. Res Vet Sci 3:78–84
Björnhag G (1972) Separation and delay of contents in the rabbit colon. Swed J Agric Res 2:125–136
Björnhag G (1981a) The retrograde transport of fluid in the proximal colon of rabbits. Swed J Agric Res 11:63–69
Björnhag G (1981b) Separation and retrograde transport in the large intestine of herbivores. Livest Prod Sci 8:351–360
Björnhag G (1987) Comparative aspects of digestion in the hindgut of mammals. The colonic separation mechanism (CSM). Dtsch tierärztl Wschr 94:33–36
Bonfert A (1928) Vergleichende Untersuchung über die Homologie der Darmteile bei Nagetieren unter teilweiser Berücksichtigung der arteriellen Blutversorgung. Anat Anz 65:369–398
Gabella G (1981) On the musculature of the gastrointestinal tract of the guinea-pig. Anat Embryol 163:135–156
Gorgas M (1967) Vergleichend-anatomische Untersuchungen am Magen-Darm-Kanal der Sciuromorpha, Hystricomorpha und Caviomorpha (Rodentia). Z Wiss Zool 175:331–404
Gosling LM (1979) The twenty-four hour activity cycle of captive coypus (Myocastor coypus). J Zool 187:341–367
Grzimek B (1979) Grzimeks Tierleben. Säugetiere 2. Deutscher Taschenbuch Verlag, München, pp 419–421
Hamilton DL, Roe WE (1977) Electrolyte levels and net fluid and electrolyte movements in the gastrointestinal tract of weanling swine. Can J Comp Med 41:241–250
Harder W (1950) Zur Gliederung des Enddarmes der Nagetiere. Anat Anz Erg H 97:235–238
Holtenius K, Björnhag G (1985) The colonic separation mechanism in the guinea pig (Cavia porcellus) and the chinchilla (Chinchilla laniger). Comp Biochem Physiol 82A:537–542
Hörnicke H, Schürg A, Krattenmacher R (1985) Kotfressen (Koprophagie) beim Sumpfbiber (Nutria) —eine normale, für die Nährstoffversorgung wichtige Verhaltensweise. Der deutsche Pelztierzüchter 50:161–162
Illman O (1961) The coypu (Myocastor coypus Molina) as a laboratory animal. J Anim Tech Assoc 12:8–10
Jacobshagen H (1937) Mittelund Enddarm. In: Bolk L, Goeppert E, Kallus E, Lubosch W (eds) Handbuch der vergleichenden Anatomie der Wirbeltiere. Bd 3, Verlag Urban and Schwarzenberg, Berlin pp 563–724
Kämmerer D, Wetzig H (1966) Histologische und histochemische Untersuchungen am Colon des Sumpfbibers (Myocastor coypus Mol.) Morphol Jahrb 108:344–362
Koch T, Rothe G, Mosch K (1953) Beiträge zur Anatomie des Sumpfbibers. Hirzel Verlag, Leipzig
Kostanecki K (1926) Le caecum des vertébrés. Bull Int Acad polonaise. Classe sci mathém et naturelle Série B Cracovie, No Supplémentaire
Kurohmaru N, Hayakawa T, Seki M, Zyo K (1984) Morphological characteristics of the intestinal mucosa in the Afghan pika (Ochotona rufescens rufescens). Exp Anim 33:509–518
Lereboullet M (1945) Notes pour servire à l'anatomie du coipou (Myopotamus coipus, Commerson). Mem Soc Museum d'Histoire Naturelle de Strassbourg, pp 1–26
Luppa H (1961) Makroskopische, mikroskopische und topochemische Untersuchungen an der Schleimhaut des Enddarmes der Bisamratte (Ondatra zibethica L.) und einiger murider Nager. Z Mikroskop Anat Forsch 67:610–631
Sakata T, v Engelhardt W (1981) Luminal mucin in the large intestine of mice, rats and guinea pigs. Cell Tissue Res 219:629–635
Snipes RL (1978) Anatomy of the rabbit cecum. Anat Embryol 155:57–80
Snipes RL (1979) Anatomy of the cecum of the vole, Microtus agrestis. Anat Embryol 157:181–203
Snipes RL (1985) The mammalian cecum. In: Duncker H-R, Fleischer G (eds) Vertebrate Morphology. Fortschritte der Zoologie. Vol 30, Gustav Fischer Verlag, Stuttgart New York, pp 325–327
Snipes RL, Clauss W, Weber A, Hörnicke H (1982) Structural and functional differences in various divisions of the rabbit colon. Cell Tissue Res 225:331–346
Specht W (1977) Morphology of the intestinal wall. In: Kramer M, Lauterbach F (eds) Intestinal permeation. Excerpta Medica, Amsterdam, pp 4–40
Sperber I (1968) Physiological mechanisms in herbivores for retention and utilization of nitrogenous compounds. In: Isotope studies on the nitrogen chain. IAEA, Vienna, pp 209–219
Sperber I, Björnhag G, Ridderstråle Y (1983) Function of proximal colon in lemming and rat. Swed J Agric Res 13:243–256
Staaland H (1975) Absorption of sodium, potassium and water in the colon of the Norway lemming Lemmuns lemmus (L.). Comp Biochem Physiol 52A:77–80
Stahl W (1987) Physiologische Untersuchungen am Magen-DarmTrakt der Nutria (Myocastor coypus Molina, 1782). Vet Diss München, Tierärztliche Fakultät, Universität München
Wagner JA (1963) Gross and microscopic anatomy of the digestive system of the nutria, Myocastor coypu honariensis (Geoffroy). J Morphol 112:319–333
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Dedicated to Prof. K.-E. Wohlfarth-Bottermann, Institut für Cytologie und Mikromorphologie der Universität Bonn, Bonn, Federal Republic of Germany, on the occasion of his 65th birthday
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Snipes, R.L., Hörnicke, H., Björnhag, G. et al. Regional differences in hindgut structure and function in the nutria, Myocastor coypus . Cell Tissue Res. 252, 435–447 (1988). https://doi.org/10.1007/BF00214387
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DOI: https://doi.org/10.1007/BF00214387