Coccidia of wombats: correction of host-parasite relationships. Eimeria wombati (Gilruth and Bull, 1912) Comb. Nov. and Eimeria ursini Supperer, 1957 from the hairy-nosed wombat and Eimeria arundeli sp. n. from the common wombat.

Coccidial oocysts morphologically consistent with Eimeria ursini Supperer 1957, and E. tasmaniae Supperer 1957 were recovered from the feces of wild and captive hairy-nosed wombats (Lasiorhinus latifrons) in Australia. Eimeria arundeli so. n. was recovered from the feces of wild and captive common wombats (Vombatus ursinus). Eimeria arundeli oocysts are ellipsoidal to slightly ovoid 60.2--67.2 (63.7) X 40.6--47.6 (43.4); micropyle 3 in diameter usually visible; with oocyst wall granular, dark brown and occasionally opaque, 4--7 thick; inner oocyst wall clear, about 1.5 thick; small oocyst residuum present, four sporocysts ovoid 22.4--29.4 (25.8) X 12.6--15.4 (14.1) with protuberant Stieda body; opposite end of sporocyst also often slighly pointed; large granular sporocyst residuum obscuring sporozoites. Gametocytes of E. arundeli sp. n. and of an organism which is consistent with E. tasmaniae, are described developing in the lamina propria of villi in the small intestine. The stages in the hairy-nosed wombat are those described as Ileocystis wombati Gilruth and Bull 1912. It is suggested that the identification of the host of Supperer's E. ursini and E. tasmaniae as V. ursinus was in error and that the allopatric L. latifrons is the natural host. Eimeria tasmaniae Supperer 1957 is suppressed and E. wombati (Gilruth and Bull, 1912) comb. nov. is proposed and redescribed. No schizonts were identified among the endogenous stages, consistent with observations in the literature on other coccidia with similar gametocyte and oocyst structure.     

Coccidia (Eimeria tachyglossi n. sp., E. echidnae n. sp., and Octosporella hystrix n. sp.) in the Echidna, Tachyglossus aculeatus (Monotremata: Tachyglossidae)

Oocysts of Octosporella hystrix n. sp., Eimeria tachyglossi n. sp., and E. echidnae n. sp. are described from the feces of the echidna Tachyglossus aculeatus (Monotremata: Tachyglossidae) from Australia. Eimeria tachyglossi has subspherical oocysts, 26.4 × 23.7 μm in size, with a single oocyst wall; no micropyle; four ellipsoidal sporocysts 13.2 × 9.7, slightly pointed at one end, each containing two sporozoites. Eimeria echidnae has subspherical oocysts, 19.4 × 17.8 in size, with a single oocyst wall; no micropyle; four ellipsoidal sporocysts 9.8 × 7.8, blunt at both ends, each containing two sporozoites. Octosporella hystrix has ovoid or subspherical oocysts 32.9 × 29.7 in size with a thick outer and thin inner oocyst wall; no micropyle; eight sporocysts spherical or slightly subspherical 11.3 × 11.2 each containing two sporozoites lying in embrace, with an extensive granular sporocyst residuum about the equator of the sporocyst. Endogenous stages considered to be of E. tachyglossi at least, were recognized in the lamina propria and epithelium on villi in the small intestine of three echidnas.     

Some morphological and histochemical studies on the intestinal tract of the Brazilian sloth (Bradypus tridactylus)

The intestinal of the 3-toed sloth, Bradypus tridactylus, was studied macroscopically, with light microscope and with histochemical methods for mucosubstances. Macroscopically, the inner surface of the duodenum shows longitudinal and circular folds. There is no caecum, nor appendix. The large intestine consists of a short colon and a large rectal pouch, which has a thick wall. The mucosa of the small intestine has long leaf-shaped villi covered with columnar epithelium having a well developed striated border, and the goblet cells are scattered among the columnar cells. An association between neutral and acidic mucosubstances was detected in the goblet cells. The duodenal (Brunner's) glands are confined exclusively in the lamina propria of the duodenum. No Paneth cells were observed in the crypt lining. Argyrophil and argentaffin cells were found in the entire length of the intestine. The large intestine does not possess villi, but many goblet cells were observed in its mucosa.     

The microscopic anatomy of the oesophagus, stomach and intestine of the channel catfish, Ictalurus punctatus

An anatomical study of the digestive tract of the channel catfish revealed that the oesophageal mucosa was longitudinally folded and that secondary folds were occasionally located on the primary longitudinal folds. The infoldings were more numerous near the stomach. The stratified squamous epithelium covering the folds was made up of a basal layer, large mucous cells and simple squamous cells on the surface. The epithelium on the side of the folds consisted primarily of mucous secreting cells. Taste buds were observed between mucous cells on the apical portion of the oesophageal folds and were more prevalent in the cranial part of the oesophagus. The remaining layers of the oesophagus were: a lamina propria-submucosa, tunica muscularis and adventitia or serosa.
The J-shaped stomach had two regions: a large sac-shaped region containing gastric glands and a smaller, nonglandular pyloric region. The large rugae of the stomach became gradually smaller near the pylorus. There was a well developed pyloric sphincter. The mucosa included a simple columnar epithelium, a lamina propria and adventitia or serosa.
The intestine could be differentiated into a thick ascending segment, a descending segment, a thin convoluted segment and a thicker terminal segment, the rectum. Many mucosal folds containing branched villi characterized the ascending segment of the intestine. The descending and convoluted segments contained fewer folds with shorter and less-branching villi and were smaller in diameter and thinner walled. Descending and convoluted segments were also mildly convoluted and accounted for 80% of the total length of the intestine. An intestinal valve with a sphincter marked the beginning of the rectum. There was an approximately four-fold increase in the thickness of the tunica muscularis of the terminal segment of the intestine.     

Immunocytochemical localization of prostaglandin endoperoxide synthase in the bovine intestine

The localization of prostaglandin (PG) endoperoxide synthase in bovine intestine was examined immunocytochemically with polyclonal antibody raised against PG endoperoxide synthase purified from bovine seminal glands. The most intense positive staining reaction for the enzyme was present in mast cells. Mast cells were found to be widely distributed in the intestinal wall, and were particularly numerous in the lamina propria. Most of the mast cells in the lamina propria of the intestinal villi were elongated and oriented with their long axis parallel to the plane of the absorptive epithelium. In whole mount preparations of jejunal villi, mast cells were seen to form a two-dimensional network in the lamina propria. In addition to mast cells, smooth muscle cells of the inner circular muscle layer and muscularis mucosae, nerve cells and fibers, endothelial cells of arterioles, and serosal epithelial cells also showed faint to moderate staining for the enzyme. These results suggested that mast cells are the major source of PGs in the bovine intestinal wall. The characteristic arrangement of mast cells in the intestinal villi may be related to their functions in this portion of the bovine intestine.     

Schizonts and Microgametocytes of Eimeria auburnensis Christensen and Porter, 1939, in Calves

SYNOPSIS. Schizonts were found in the middle and lower third of the small intestine of two calves killed 12 and 14 days after they had been inoculated with pure cultures of oocysts of Eimeria auburnensis. The schizonts ranged from 78 to 250 μ long by 78 to 150 μ wide (mean 92 by 139.9 μ). They were usually located deep in the lamina propria near the muscularis mucosae instead of in the villi where most schizonts of Eimeria bovis are found. The schizonts of E. auburnensis resembled the previously described large microgametocytes of this species but were distinguishable morphologically and by histochemical stains. The microgametocytes were much larger than previously reported; one measured 91 by 287.5 μ.     

Histochemical distribution of four types of enzymes and mucous cells in the gastrointestinal tract of reared half‐smooth tongue sole Cynoglossus semilaevis

The histochemical distribution of acid phosphatase (ACP), alkaline phosphatase (ALP), non‐specific esterase (NSE), peroxidase (POD) and mucous‐cell types was evaluated in the gastrointestinal tract of the half‐smooth tongue sole Cynoglossus semilaevis. The enzymes were detected in the entire stretch of the gastrointestinal tract. ACP activity was found in the supranuclear region of enterocytes and the lamina propria of the intestine, as well as the cytoplasm of epithelial cells of the stomach. The staining intensity of ACP in the anterior and posterior intestines was stronger than in the stomach. ALP activity was detected in the striated border of enterocytes and muscularis of the whole intestine, lamina propria and supranuclear cytoplasm of the enterocytes in the anterior intestine, as well as in the blood vessels of the stomach. The staining intensity for ALP in the anterior intestine was stronger than in the posterior segment and the latter was stronger than in the stomach. NSE activity was detected in the cytoplasm of the epithelial cells in the entire gastrointestinal tract, with the anterior intestine showing stronger intensity than the stomach. POD activity was located in the blood cells of the lamina propria of the gastrointestinal tract and the levels in the stomach were similar to the anterior and posterior intestines. Alcian blue (pH 2·5) periodic acid Schiff (AB‐PAS) histochemical results revealed three types of mucous cells in the gastrointestinal tract. Type I cells (PAS+AB‐) were observed among the gastric mucosa columnar cells in the stomach and enterocytes in the basal region of the villi and in the middle and top regions of the intestinal villi. Type II cells (PAS‐AB+) and type III cells (PAS+AB+) were not detected in the stomach but were distributed ubiquitously among enterocytes in the middle and top regions of the intestinal villi.     

The stomach of Oreochromis niloticus has three regions

The stomach of Oreochromis niloticus was divided into three distinct regions: initial, middle and terminal, corresponding roughly to the cardiac, fundic, and pyloric portions of the mammalian stomach. Grossly, the organ showed initial and terminal portions, the former connected to the distal part of the oesophagus and the latter to the proximal portion of the intestine. There was also a middle region, forming a large blind diverticulum communicating with the first two at their point of junction. The initial or cardiac region was shorter than the middle region but longer than the terminal one, and had a smooth surface devoid of gastric pits. The epithelium in this region was simple columnar devoid of goblet cells, with glandular regions in the lamina propria. The mucosa of the middle or fundic region had gastric pits lined by columnar epithelium, and simple tubular glands filled most of the lamina propria. The terminal or pyloric part of the stomach was very short and its mucosa was slightly folded and devoid of both gastric pits and mucous glandular cells. The lining epithelium of this portion of the stomach was simple columnar and a few goblet cells were seen at its junction with the first part of the intestine. The tunica muscularis of the stomach contained skeletal muscle in the initial and terminal regions, usually intermingled with smooth muscle fibres. Skeletal muscle fibres were also observed in the first portion of the small intestine, near the junction with the stomach.     

Restoration of the jejunal mucosa in rats refed after prolonged fasting

To investigate the importance of body fuel depletion on gut rehabilitation after food deprivation, we compared the kinetics of jejunal mucosa alteration and restoration in rats that were refed after reaching different stages in body fuel depletion. Rats (P2) were refed while still in the so-called phase II, where body protein utilization is minimized, whereas rats (P3) were refed when they had reached the stage of increasing protein utilization (phase III). There was a significant decrease in total mass of intestine (P2, -30%; P3, -40%) and jejunal mucosa (P2, -52%; P3, -60%), as well in the size of the crypts (P2, -15%; P3, -36%) and villi (P2, -37%; P3, -55%). Structural changes of the mucosa included disappearance of some villi and a reduction in the size and number of crypts. Despite the larger morphological alterations in P3, the restoration of mucosa was as fast and complete after only 3 days of refeeding for both P2 and P3 rats. The respective roles of the mitosis pressure and of the lamina propria dynamics were studied. The rapid reversibility of the gut mucosal alterations due to fasting might constitute an integrative process.     

尾斑瘰螈主要消化器官组织结构观察

本研究采用组织学方法对尾斑瘰螈(Paramesotriton caudopunctatus)的消化器官进行了显微结构观察。结果表明,尾斑瘰螈食管较短,胃、肠壁组织结构分为黏膜层、黏膜下层、肌层和外膜,小肠前段的黏膜下层缺失。胃黏膜层中有许多胃腺,胃腺细胞胞质含嗜酸性颗粒。小肠前段绒毛细长密集,中段、后段逐渐短小稀疏,在黏膜层的固有膜中没有肠腺分布。肝实质中肝小叶界限不明显,肝小叶内有大量色素颗粒成团分布。     

B-lymphocyte responses in the large intestine and mesenteric lymph nodes of mice infected with Eimeria falciformis (Apicomplexa)

B-cell responses of 3 immunoglobulin isotypes (IgA, IgG, and IgM) were investigated in the large intestine and mesenteric lymph nodes (MLN) of naive or immune mice after inoculation of oocysts of Eimeria falciformis. Primary and anamnestic IgA and IgG lymphocyte responses to E. falciformis occurred in the large intestine of nonimmune and immune mice, respectively. IgA-containing lymphocytes (IgAc) were the largest population of responding B cells in the large intestine. In infected mice, IgAc accumulated in the apical portion of the lamina propria, whereas IgG-containing lymphocytes (IgGc) were more numerous at the base of the lamina propria. No significant increase in the number of IgM-containing lymphocytes (IgMc) was observed in the lamina propria of the large intestine. Primary but no anamnestic B-cell responses occurred in the MLN, and immune mice actually had reduced numbers of IgAc and IgGc in the MLN when compared with naive mice. IgGc were the largest population of responding B cells in the MLN. Thus, IgAc appear to accumulate preferentially at the site of parasite development, whereas IgGc are primarily localized deeper in the lamina propria of the large intestine and in the draining lymph nodes of mice infected with E. falciformis.     

Coccidiosis of sandhill cranes (Grus canadensis) wintering in New Mexico

The feces of 212 sandhill cranes (Grus canadensis) collected in central New Mexico from October 1982 to January 1983 and from October 1983 to January 1984 were examined to determine the prevalence of coccidial oocysts. One hundred forty-five granulomatous nodules from the viscera of 64 cranes and samples of lung, small intestine, and large intestine from 58 birds were examined by light and transmission electron microscopy for the presence of intestinal or extraintestinal coccidiosis. Of the 212 fecal samples, 160 (75%) were positive for oocysts of Eimeria, including E. gruis in 139 (66%) and E. reichenowi in 118 (56%) of the samples. Eimeria bosquei sp. n. was found in two (approximately 1%) of the fecal samples. Subspheroid to ovoid oocysts of this new species are 19-27 X 14-19 (23.6 X 17.1) micrograms with ovoid sporocysts 10-14 X 7-11 (12.3 X 9.3) micrograms. A rough, heavily pitted outer oocyst wall, sporocyst residuum, Stieda and substieda bodies, and multiple polar bodies are present. The polar bodies, of varying sizes, always aggregate at the apex of the sporulated oocyst. An Adelina sp. was found in one (0.5%) crane. Coccidian developmental stages were found in the epithelium and lamina propria of the small and large intestine. Disseminated granulomatous nodules were found in the oral mucosa, esophagus, heart, descending aorta, liver, small intestine, mesenteries, and parietal peritoneum. Unique cell types resembling coccidian asexual and sexual stages were observed by light and electron microscopy in some of the nodules.     

Duodenal microanatomy of the domestic cat (Felis catus)

Duodenal samples were taken from similar locations in six cats, processed, stained, and examined via light microscope. There were no prominent circular folds (plicae circulares) or stratum compactum (lamina subglandularis). The 1072 microns x 201 microns villi were covered by 46 microns high columnar epitheliocytes proximally which decreased in height (41 microns) distally and displayed a 1.1-1.7 microns striated border. Globular leukocytes, mononuclear cells, and twenty-eight goblet cells (exocrinocytus calciformis) per villus were seen. The intestinal gland (crypt of Lieberkuhn) epithelium was 20 microns tall and had a less distinct striated border. The 515 microns simple straight tubular intestinal gland layer displayed distal branching. Many mitotic figures, 12 goblet cells per gland, and occasional columnar to triangular cells with red cytoplasmic granules were seen. The thickness of the lamina propria mucosa (glandular portion) decreased from proximal to distal (563-465 microns). The lamina muscularis mucosa had two layers and decreased in thickness distally (71-28 microns). The proximal muscularis mucosa was penetrated by the ducts of submucosal (Brunner's, duodenal) glands. The tela submucosa decreased in thickness distally (593-192 microns) and contained submucosal glands with 11.5-75 microns lumina for the first 1.5-2.5 cm. However, submucosal glands could be found to a distance of 8 cm. The glandular epithelium ranged from 7.5-22.5 microns in height. Only one type of secretory cell was observed, with both mucous and serous properties. The tunica muscularis ranged from 190-1425 microns (median thickness of 557 microns) and had two layers.     

Intestinal Cryptosporidium sp. infection in the Egyptian tortoise, Testudo kleinmanni

An adult Egyptian tortoise (Testudo kleinmanni) presented with clinical signs of enteritis and died 5 weeks after initiation of antibiotic therapy. Histological examination of the small intestine revealed heavy infection with Cryptosporidium sp.; over 80% of epithelial cells harboured the pathogen. No Cryptosporidium developmental stages were present in the stomach or the lungs. The intestinal lamina propria and mucosa were infiltrated by heterophils, lymphocytes and macrophages. The present study constitutes the first report of Cryptosporidium sp. infection in T. kleinmanni, and the first histological documentation of intestinal cryptosporidiosis in Chelonia.     

Concomitant cryptosporidia, coronavirus and parvovirus infection in a raccoon (Procyon lotor).

A juvenile raccoon (Procyon lotor) was found moribund near Fort Collins, Colorado (USA). Upon examination, the raccoon was dehydrated, had a mucopurulent oculonasal discharge and diarrhea, and was euthanized. Postmortem examination revealed emaciation, severe fibrinous gastroenteritis and a small, firm liver. Histopathological findings included blunting of villi, infiltration of lamina propria with neutrophils and plasma cells, and mild bronchopneumonia. Cryptosporidium sp. was demonstrated on intestinal villi and coronavirus and parvovirus were identified in feces. Fluorescent antibody test for rabies was negative and no evidence of canine distemper was found.     

Histological study of Trichosomoides nasalis (Nematoda: Trichinelloidea) in the nasal cavities of the murid Arvicanthis niloticus, with associated pathology

Histological study of the nasal cavities and upper maxillae of Arvicanthis niloticus naturally infected with Trichosomoides nasalis shows that the female worms reside in the epithelial monolayer of the nasal mucosa of the posterior and median cavities. Eggs laid by T. nasalis were infiltrated between the female body wall and the epithelial lining. Small groups of eggs, mixed with mucus and polymorphonuclear cells, were found in the nasal lumen, freed by rupture of the stretched epithelium. Two females and a few eggs were also found in the connective tissues. One male was found in a female uterus and two were apparently in the lumen of the nasal cavity but the surrounding tissues were disrupted. No male was identified in the lamina propria of the mucosa. However, significant inflammatory lesions occurred in the lamina propria, similar to those induced by the males of Anatrichosoma spp. which live in this part of the mucosa. In rodents, the lesions resulted in rhinosinusitis characterised by a lymphocytic infiltration leading to nasal obstruction.     

The effect of large doses of Nematodirus battus on the histology and biochemistry of the small intestine of lambs

Coop R.L., Angus K.W. and Mapes C.J. 1973. The effect of large doses of Nematodirus battus on the histology and biochemistry of the small intestine of lambs. International Journal for Parasitology3: 349–361. Large single and multiple doses of Nematodirus battus alter the structure of the small intestine, producing a low flattened, convoluted type of mucosa with extensive cellular infiltration of the lamina propria. The brush borders of the epithelial cells on the surface of the villi are narrow and the microvilli sparse and distorted.There is a reduction in alkaline phosphatase and disaccharidase activity in the mucosa of infected lambs, whereas dipeptidase activity is unaffected. The changes in enzyme activity are thought to arise from damage to mature epithelial cells on the villi.Alkaline phosphatase and disaccharidase activity in the mueosa of lambs killed 18 days after infection is correlated with the dry matter content of the faeces.     

CELL PROLIFERATION IN WALKER TUMOUR GROWING IN THE STOMACH WALL

Tumour cells from a Walker carcinosarcoma 256 were implanted in the gastric mucosa in rats. The tumour grew and infiltrated the lamina propria and the submucosal space after 7 days. It appeared to grow faster in the submucosal space than in the lamina propria. The cell proliferation was therefore studied separately in: (1) the tumour in the lamina propria, (2) the main tumour mass and (3) the tumour periphery, defined as the cells located within the outer 100–120 μm of the tumour. Mitoses arrested with vinblastine, cells labelled with tritiated thymidine and the grain count per labelled cell were studied at the three different sites. The rate of cell proliferation in the tumour was highest in the lamina propria, lower in the centre of the main tumour mass, and lowest at the periphery. Cell loss might explain the discrepancy between the rate of cell proliferation and the actual tumour growth. The factors that influence tumour cell proliferation in the different parts of the tumour are discussed.     

Cell proliferation in Walker tumour growing in the stomach wall.

Tumour cells from a Walker carcinosarcoma 256 were implanted in the gastric mucosa in rats. The tumour grew and infiltrated the lamina propria and the submucosal space after 7 days. It appeared to grow faster in the submucosal space than in the lamina propria. The cell proliferation was therefore studied separately in: (1) the tumour in the lamina propria, (2) the main tumour mass and (3) the tumour periphery, defined as the cells located within the outer 100-120 mum of the tumour. Mitoses arrested with vinblastine, cells labelled with tritiated thymidine and the grain count per labelled cell were studied at the three different sites. The rate of cell proliferation in the tumour was highest in the lamina propria, lower in the centre of the main tumour mass, and lowest at the periphery. Cell loss might explain the discrepancy between the rate of cell proliferation and the actual tumour growth. The factors that influence tumour cell proliferation in the different parts of the tumour are discussed.     

The localization of macrophage subsets and dendritic cells in the gastrointestinal tract of the mouse with special reference to the presence of high endothelial venules

Summary This study concerns the distribution of macrophages and dendritic cells (DC) in the gastrointestinal tract of the mouse. Heterogeneity of macrophage population was found by using the MOMA-1, MOMA-2, ERTR-9, Mac-1 and F4/80 monoclonal antibodies. MOMA-1, ERTR-9, Mac-1 and F4/80+ cells were detected mostly at the villous cores in the lamina propria of the villi, whereas MOMA-2+ cells were primarily found around the crypts at the base of the villi. These MOMA-2+ cells revealed a granular appearance throughout the cytoplasm and displayed a strong acid phosphatase (AcPh) activity. Few MOMA-2+ cells were seen at the top of the villi in the epithelium. Although MOMA-1 and ERTR-9+ cells have similar morphology and the same distribution patterns in the lamina propria, they are likely different populations, because in Peyer's patches (PP), MOMA-1+ cells were present, whereas ERTR-9+ cells could not be detected. Both populations displayed AcPh activity. Strongly stained Mac-1+ cells were abundantly seen in the lamina propria of the small intestine. F4/80+ cells were rare. NLDC-145+ cells with AcPh activity and weak Ia staining were also found. In the PP-associated villi and in the T-dependent area of PP, dendritic NLDC-145+ cells, which were strongly Ia positive, were detected. MIDC-8+ cells were found only in the T-dependent area. Few NLDC-145+ cells (dendritic cells) were found in the upper part of the oesophagus. These cells were also stained with the MIDC-8 antibody. The MECA-325 monoclonal antibody recognized high endothelial venules (HEV) in PP and blood vessels at the base of the villi of the jejunumileum and caecum. Unlike in PP, the endothelium of the venules in the villi was flat.