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Necropsy-based Wild Fish Health Assessment
Published on: September 11, 2018
The digestive system of the fish ectoparasite Dolops ranarum (Crustacea: Branchiura)
Annemarie Avenant-Oldewage1, J G van As1
1Department of Zoology, Rand Afrikaans University, Johannesburg, 2000.
Abstract:
Reconstructions from serial sections reveal that the digestive system consists of a pharynx esophagus, crop, midgut, and rectum. Two main stems from the branched enteral diverticula are connected to the lateral regions of the crop by right rind left arms. Glandular tissue surrounds the enteral diverticula proximally. A strong sphincter separates the crop and midgut, whereas the midgut and rectum are separated by a weak sphincter. Cuboidal epithelium lines the pharynx, esophagus, crop, and rectum, whereas cuboidal and club-shaped epithelia line the midgut. The cuboidal cells possess elongated nuclei and numerous vacuoles, suggesting that absorption takes place in the midgut.
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