Ultrastructure and Morphometric Analysis of Interstitial Cells of Cajal in the Gastric Wall of the Bullfrog (Rana catesbeiana)

Interstitial cells of Cajal (ICC) play a vital role in the gastrointestinal motility. However, information on ICC in lower vertebrates is rare. Here, ICC and ICC-like features of the gastric wall in the bullfrog (Rana catesbeiana) were observed by light microscopy and transmission electron microscopy. The lengths and distances of the ICC/ICC-like features were measured by morphometric analysis. The gastric wall contained mucosa, submucosa, tunica muscularis, and serosa. The gastric glands contained mucous cells and oxynticopeptic cells. The ICC with 1–3 processes were located among smooth muscle cells (SMC) of the tunica muscularis. Moreover, the ICC-like features were observed among oxynticopeptic cells of the mucosa. The processes of ICC established direct contacts with SMC. Also, the gap junctions were observed between the processes of ICC and nerve fiber bundles in the tunica muscularis. The multivesicular bodies, including shedding exosomes, were frequently observed between ICC and SMC. In addition, ICC-like features and their processes were observed in close proximity to oxynticopeptic cells and blood vessels. Our findings illustrated that ICC are present in the gastric tunica muscularis, and ICC-like features were in the mucosal lamina propria of the gastric wall of R. catesbeiana. These histological evidences supported the notion that ICC are implicated in gastric motility.

Gastric Balloon Implantation as Part of Morbid Adiposity Therapy Changes the Structure of the Stomach Wall

Purpose: The implantation of a gastric balloon (also known as intragastric balloon) is an established and reversible endoscopic procedure for adiposity therapy. Structural changes of the stomach wall are expected to occur with gastric balloon implantation; however, until now these changes have rarely been investigated. Methods: We compared the histological structure of the stomach wall after gastric-sleeve resection in a group of patients following gastric balloon implantation and a group without previous gastric balloon implantation. Results: Following gastric balloon implantation, the tunica muscularis was found to be significantly thicker than without gastric balloon implantation. The enlarging of the tunica muscularis is not caused by hyperplasia of the leiomyocytes, but by hypertrophy of the leiomyocytes and an increase in collagen fibers (fibrosis). Conclusion: A longer-lasting hypertrophy of the tunica muscularis, particularly in the corpus, should be taken into account when surgical treatment follows gastric balloon implantation. The staple suture height should be adjusted to the altered tissue composition since reduced tissue elasticity must be expected due to fibrosis.

Histomorphological and Histochemical Studies on Proventriculus in Guinea Fowl (Numida meleagris)

Background: The proventriculus, component of digestive system of bird secretes hydrochloric acid and pepsinogen which helps the churning of food material that takes place in ventriculus. Pepsinogen produces pepsin and it smashes the peptide bonds of amino acid of food material. Methods: The twelve proventriculus samples of Guinea fowl birds were fixed in 10% neutral buffered formalin and Bouin’s fluid for histological procedure while chilled acetone and chilled ethanol were used as the fixatives for histochemical studies. The fresh unfixed samples were used on cryostat for studies of succinic dehydrogenase enzyme.Result: Histomorphologically the proventriculus of Guinea fowl was observed as the typical tubular component with four tunics from inside to outside as tunica mucosa, tunica sub mucosa, tunica muscularis and tunica serosa. The submucosal layer comprised with proventricular submucosal gland (PVSMG) which was encapsulated by elastic fibers. Tunica muscularis was inner longitudinal and outer circular layer, while the tunica serosa was observed with surrounding adipose tissue as the connective tissue constituent to endow the access of nutritional supply in the form of blood vessels. The luminal surface of proventricular submucosal glands has shown the significant activity of glycogen while intercalated, intralobular and interlobular ducts have exhibited the weak activity towards the same. The glandular cell rod of PVSMG, serosal layer and adjoining connective tissue with blood vessels has exhibited very weak activity of alkaline phosphatase. Mucosal folds and lumen of PVSMG has shown the weak activity of acidic phosphatase but the serosal limiting membrane has shown very weak activity. The succinic dehydrogenase activity was seen in the connective tissue septa of submucosal glandular cellular rods and the intense activity was observed at tunica muscularis.

Comparative Features of the Upper Alimentary Tract in the Domestic Fowl (Gallus gallus domesticus) and Kestrel (Falco tinnunculus): A Morphological, Histochemical, and Scanning Electron Microscopic Study

The avian alimentary tract has evolved into different histologic structures to accommodate the physical and chemical features of several food types and flight requirements. We compared the esophagus, proventriculus, and gizzard of the domestic fowl, Gallus gallus domesticus (GGD) and kestrels, Falco tinnunculus (FT) using immunohistochemistry and scanning electron microscopy with various stains and lectins [Dolichos biflorus agglutinin (DBA) and Ricinus communis agglutinin I (RCA120)], and α-smooth muscle actin (α-SMA). The esophagus of GGD demonstrated thickened epithelium, muscularis mucosae, and inner circular longitudinal tunica muscularis layers; moderate outer longitudinal tunica muscularis layers; and a true crop. In contrast, the esophagus of FT showed a thin epithelium, no muscularis mucosae, moderate inner longitudinal and thick outer circular tunica muscularis layers, and no true crop. In the proventriculus, the nature of the secretion in GGD was neutral, but that of FT was acidic and neutral. In the gizzard, the muscle coat of GGD by α-SMA had no muscularis mucosae, unlike FT, which had muscularis mucosae. In summary, there are many histologic differences between GGD and FT to meet their different physiologic needs, such as feeding.

Expression of the Regulated Isoform of the Electrogenic Na+/HCO3- Cotransporter, NBCe1, is Enriched in Pacemaker Interstitial Cells of Cajal

Interstitial cells of Cajal (ICC) generate electrical slow waves, which are required for normal gastrointestinal motility. The mechanisms for generation of normal pacemaking are not fully understood. Normal gastrointestinal contractility and electrical slow wave activity depend on the presence of extracellular HCO3-. Previous transcriptional analysis identified enrichment of mRNA encoding the electrogenic Na+/HCO3- cotransporter (NBCe1) gene (Slc4a4) in pacemaker myenteric ICC in mouse small intestine. We aimed to determine the distribution of NBCe1 protein in ICC of the mouse gastrointestinal tract, and to identify the transcripts of the Slc4a4 gene in mouse and human small intestinal tunica muscularis. We determined the distribution of NBCe1-immunoreactivity (NBCe1-IR) by immunofluorescent labeling in mouse and human tissues. In mice, NBCe1-IR was restricted to Kit-positive myenteric ICC of the stomach and small intestine and sub-muscular ICC of the large intestine; that is the slow wave generating subset of ICC. Other sub-types of ICC were NBCe1-negative. Quantitative real time PCR identified >500 fold enrichment of Slc4a4‑207 and Slc4a4‑208 transcripts (IP3-receptor binding protein released by IP3" (IRBIT) regulated isoforms) in Kit expressing cells isolated from KitcreERT2/+, Rpl22tm1.1Psam/Sj mice and from single GFP-positive ICC from Kittm1Rosay mice. Human jejunal tunica muscularis ICC were also NBCe1-positive and SLC4A4‑201 and SLC4A4‑204 RNAs were >300 fold enriched relative to SLC4A4‑202. In summary, NBCe1 protein expressed in ICC with electrical pacemaker function is encoded by Slc4a4 gene transcripts that generate IRBIT regulated isoforms of NBCe1. In conclusion Na+/HCO3- cotransport through NBCe1 contributes to the generation of pacemaker activity in subsets of ICC.

Effect of Different Dietary Inclusion Levels of Sunflower Meal and Multi-Enzyme Supplementation on Performance, Meat Yield, Ileum Histomorphology, and Pancreatic Enzyme Activities in Growing Quails

This study aimed to investigate the effect of dietary sunflower meal (SFM) and multi-enzyme levels on performance, carcass traits, intestinal histomorphology and pancreatic enzyme production in quails. Three hundred and twenty, 1-day-old quail chicks were divided into 8 groups with 4 replicates consisting of 10 birds each in the group. The experiment was randomized design consisting of a 4 × 2 factorial arrangement, with four levels of SFM (0%, 10%, 15%, or 20%) and two levels of multi-enzyme (0.0 or 1.0 g/kg) inclusion in the diet. The body weight, body weight gain, and feed conversion ratio were negatively influenced by the 15% and 20% SFM (p < 0.01) but were not affected by the 10% SFM for 6 week age. The relative gizzard (p < 0.05) weights significantly increased with 20% SFM, but the relative breast weight decreased (p < 0.01). The relative liver weight increased by the addition of enzymes in the diet (p < 0.05). The villus width (p < 0.01) and villus surface area (p < 0.05) of ileum increased linearly with SFM, whereas the villus height (p < 0.01), villus height: crypt depth (p < 0.01) and tunica muscularis thickness (p < 0.01) decreased linearly with SFM. Consequently, it is possible to say that the birds with the least absorptive same weight are the most efficient. The addition of multi-enzyme increased villus height and crypt depth but decreased tunica muscularis thickness of ileum (p < 0.01). Chymotrypsin activity in the pancreas decreased linearly with SFM (p < 0.01). Amylase activity in the pancreas decreased significantly with the addition of the multi-enzyme (p < 0.05). As a result of the study, SFM can be used at a 10% level in growing quail diets with beneficial effects on the absorption surface area. The effects of enzyme supplementation on parameters measured were less pronounced than the SFM inclusion level that higher villus height and lower tunica muscularis thickness were determined in multi-enzyme-fed birds compared to those untreated counterparts.

Pathological findings in North Sea and Baltic grey seal and harbour seal intestines associated with acanthocephalan infections

Grey seals Halichoerus grypus and harbour seals Phoca vitulina are common seal species in the North and Baltic seas and final hosts of Corynosoma acanthocephalans. C. strumosum and C. magdaleni infect the small intestines of both seal species. In contrast to harbour seals, Baltic grey seals in the past have regularly displayed severe C. semerme infections in the caecum and colon, with associated tunica muscularis hypertrophy, inflammation and ulcerations as part of the Baltic seal disease complex (BSDC). Pathogenesis and correlation of acanthocephalan infections with these lesions are still unknown. This study describes the intestinal pathology and parasitic distribution in each seal species. Grey seal (n = 83) and harbour seal (n = 1156) intestines of all age groups and sexes, collected in Poland, Germany and Estonia from 1998 to 2017, were investigated. Most harbour seals came from the North Sea, whereas grey seals were predominantly derived from the Baltic Sea. Both species featured mild to moderate small intestinal infections. Grey seals showed colonic infections not found in harbour seals and featured a chronic erosive to ulcerative, eosinophilic or lympho-plasmacytic colitis with tunica muscularis hypertrophy, indicating still prevailing clinical signs of the BSDC. Harbour seals displayed granulomatous, eosinophilic, lympho-plasmacytic or catarrhal enteritis. The prevalence of acanthocephalan infections in harbour seals increased from 2012 onwards. Furthermore, significant associations between acanthocephalan infection and the presence of intestinal inflammation were found for both seal species. This study suggests that the level of acanthocephalan infection and associated lesions are suitable seal population health indicators, with the colon being a specific target organ for Baltic grey seal health monitoring.

Histology of Watersnake (Enhydris Enhydris) Digestive System

This research aimed to study the histology of the digestive system of the watersnake (Enhydris enhydris). The digestive system taken was the esophagus, stomach, frontal small intestine and the back of the large intestine from three watersnakes. The samples were then made into histological preparations with hematoxylin-eosin (HE) staining and observed exploratively. The results showed that the digestive system of the watersnake was composed of layers of tissue, namely the mucosa, tunica submucosa, tunica muscularis, and serous tunica. Mucosal mucosa consisted of the lamina epithelium, lamina propria, and mucous lamina muscularis. The submucosal tunica consisted of connective tissue with blood vessels, lymph, and nerves. The muscular tunica was composed of circular muscles and elongated muscles. The serous tunica consisted of a thin layer of connective tissue that was covered by a thin layer of the mesothelium (mesothelium). The histological structure of the snake digestive system is not much different from the reptile digestive system. However, in the small intestine of the snake, Brunner, and liberkhun glands are not found. Lamina epithelial in the small intestine of the snake is composed of the layered cylindrical epithelium.

Ultrasonographic and pathological findings of grade III cervico vaginal prolapse in a pregnant buffalo

The present study records ultrasonographic (USG) and pathological findings of grade III cervico vaginal prolapse in a buffalo. There was a rare involvement of urinary bladder and intestines in the prolapsed mass. Urinary bladder appeared as anechoic region surrounded by hyperechoic circumferential, whereas intestines appeared as brief hypoechoic area in USG. Intriguingly, the histopathological investigation correspondingly showed marked discontinuation of uterine musculature especially of inner circular layer of tunica muscularis. Hyaline degeneration characterized by swollen and eosinophilic fibres and early necrobiotic changes characterized by few mononuclear cells infilteration.