Immunohistochemical evaluation of the goat forestomach during prenatal development

Here we report the detection and distribution of synaptophysin (SPY), non-neuronal enolase (NNE), glial fibrillary acidic protein (GFAP), vimentin (VIM), neuropeptide Y (NPY), and vasoactive intestinal peptide (VIP) expression in the goat forestomach during prenatal development. A total of 140 embryos and fetuses were examined to evaluate protein expression from the first stage of prenatal life until birth. In all cases, SPY immunoreactivity was detected at 53 days gestation in the lamina propria-submucosa, tunica muscularis, serosa, and myenteric plexuses. Immunoreactivity to NNE was observed at 64 days gestation in the same locations as well as the epithelial layer. Glial cells were found at 64 days as indicated by signals corresponding to GFAP and VIM at 39 days. Positive staining for NPY and VIP was observed at 113, 75, and 95 days in the rumen, reticulum, and omasum, respectively, in the lamina propria-submucosa, tunica muscularis, and myenteric plexuses of each of these gastric compartments. These findings indicate possible preparation of the fetal goat forestomach for postnatal function. Compared to other ruminant species, neuroendocrine cells, glial cells and peptidergic innervations markers were detected earlier compared to sheep but at around the same stage as in deer.     

Is Lamina Muscularis Mucosae Present in the Ruminal Mucosa of Cattle?

The cells in the condensed fibrous layer in the lamina propria of the ruminal mucosa of the calves and cows were studied at the light microscopic level. Abundant actin-immunoreactive cells were detected both in the calves and cows, while desmin-immunoreactive cells were moderate in frequency in the cows and low or absent in the calves. Vimentin-immunoreactive cells were abundant in the cows but moderate to low in frequency in the calves. These cells were distributed to form a condensed layer being more abundant in the ruminal papillae than the interpapillar mucosae in the cows and equal in the papillae and interpapillar mucosae in the calves. At the ultrastructural level, smooth muscle cells and fibroblasts were abundant in the deep core of the ruminal papilla of the cows. The present results suggest that the condensed fibrous layer revealed in the ruminal mucosae contains smooth muscle cell population which could be regarded as the specialized lamina muscularis mucosae.     

Muscular architecture and VIP-like immunoreactive nerves in the gastroduodenal junction of the chicken

The muscular architecture and the distribution of nerves with vasoactive intestinal polypeptide-like (VIP-like) immunoreactivity were examined in the gastroduodenal junction of the chicken. Both the outer and the inner muscle layers (tunica muscularis) and the muscularis mucosae were examined. The inner muscle layer was divided into two parts, namely its inner and outer parts. The outer muscle layer was not present in the pyloric part but was found in the proventriculus and the duodenum. The muscle strands of the outer muscle layer ran longitudinally but were absent at the isthmus and the pylorus. Most of the outer part of the inner muscle layer was located in or close to the pyloric part. The muscle strands in the outer part connected the pyloric part with other regions, namely the craniodorsal muscle, the tendinous centres and the isthmus. The inner part of the inner muscle layer was widely distributed in the stomach. In the pyloric part, the muscle strands of this layer followed a circular or spiral course. The muscularis mucosae was not present in the caudodorsal and cranioventral muscles of the gizzard. In addition, VIP-like immunoreactive nerve fibres were predominantly distributed in the inner part of inner muscle layer of the pyloric part. These results suggest that the ventriculopyloric orifice and the pyloric part itself constrict with a sphincter-like action.Abbreviations VIP vasoactive intestinal polypeptide     

Reticular Groove of the Domestic Ruminants: Histochemical and Immunocytochemical Study

The reticular groove mucosa of adult cattle, buffalo and sheep was investigated by histochemical and immunocytochemical techniques. Intense NADPH‐d staining was observed in the folds of the epithelium mucosa and at the bottom of the reticular groove in all domestic ruminants studied. The NADPH‐d staining showed that the innervations of the tunica muscularis of the reticular groove lip were composed of nerve corpuscles, nerve fibres and nerve cells of the mucosa epithelium. SEM analysis showed an intense nitric oxide synthase (NOS) I immunoreactivity in deep and medium cellular layers. It is interesting to note that the same morphologies were observed in samples of the mucosa epithelium, and of the tunica muscularis processed by NADPH‐d and in those processed by immunogold techniques. This study has demonstrated that nitric oxide (NO) is involved in the rumination activity and that it plays a double role in this activity in the reticular groove of all domestic ruminants studied: (1) NO plays a role similar to the one it has in the mucosa epithelium of all the other compartments of the ruminant forestomach, (2) The lip sections of the reticular groove has shown abundant innervations that may indirectly coordinate and control the forestomach motility through the direct activation of the nitrergic (nitroxidergic) nerve cells and nerve fibres.     

Distribution of substance P-like immunoreactivity in the enteric neurons of the large colon of normal and amitraz-treated ponies: an immunocytochemical study

The distribution of the putative motor excitatory neurotransmitter, substance P, was studied immunocytochemically in the left dorsal colon of four normal control ponies and three ponies with amitraz-induced impaction colic. Substance P-like immunoreactivity in the control ponies was observed in nerve fibres in all layers of the bowel wall and in the nerve cell bodies of the enteric ganglia. The substance P-like immunoreactivity was clearly more intense in the cell bodies of submucosal ganglia than in those of the myenteric ganglia. The internodal nerve strands of the myenteric plexus were very rich in substance P-like immunoreactivity and within the ganglia they formed dense varicose networks around the neuronal cell bodies. Nerve bundles rich in substance P-like immunoreactivity diverged inward from the myenteric plexus to contribute an abundance of varicose immunoreactive fibres to the circular muscle of the tunica muscularis. Nerve fascicles with substance P-like immunoreactivity were sparse in the longitudinal muscle except in the thickened taenial band. In the submucosa many of the nerve fibres with substance P-like immunoreactivity appeared to arise from ganglionic cell bodies. Immunoreactive fibres commonly condensed around arterial vessels in the submucosa. Fine immunoreactive nerve fascicles from the submucosal plexus also projected internally to supply the muscularis mucosae and form periglandular arrays in the lamina propria. The distribution of substance P-like immunoreactivity in the normal equine colon differed in some respects from patterns observed in large intestines of other mammals. When the colons of normal and amitraz-treated ponies were compared no differences were discerned in the distribution or intensity of substance P-like reactivity.     

Morphological study of the Forestomach of the Japanese Serow (Capricomis crispus)

Details of the morphology of the forestomach of the Japanese serow (Capricornis crispus) were examined macroscopically, and by light and scanning electron microscopy. The rumen was sac-like in shape, and the right accessory longitudinal groove was not visible externally. The reticulum was relatively small, while the omasum was oval and large. Inside the rumen, even in the dorsal sac, the ruminal papillae were densely distributed, although absent on the pillars. The caudodorsal coronary pillar was indistinct. In the ruminoreticular fold, ruminal papillae were observed even on the reticulum side. In the reticulum, the primary reticular fold was apparent and the ill-defined secondary folds were also detected in some reticular cells. In the omasum, the omasal laminae of four sizes were recognized. The fourth order of laminae was occasionally absent. Histological sections of ruminal papillae revealed that softly keratinized epithelium covered the entire ruminal mucosa. In the reticulum, soft keratinized epithelium was observed throughout, with the exception of the tips of reticular papillae on which the epithelium showed evidence of hard keratinization. The epithelium of the omasal laminae was moderately keratinized. On the floor of the reticular groove, interlaminar area and in the omasal groove, the accumulations of numerous eosinophilic cells were observed in the superficial region. Under the scanning electron microscope, shallow transverse grooves were seen on the surface of the ruminal papillae. In general, the surface structure seemed to be similar to that of sheep rather than cattle. Cellular formations of the collagen fibrils were observed at the subepithelial region. In conclusion, examination of the forestomach allows classification of the Japanese serows as requiring an intermediate type of feeding habit and being between concentrate selectors and grass-roughage eaters from a morphological view.     

牛羊养殖中前胃疾病鉴别诊断方法

牛羊都是反刍动物,它们拥有4个胃,分别是瘤胃、网胃、瓣胃和真胃。前3个胃统称为前胃,在前胃中有大量的可以分解和消化饲料中粗纤维的细菌,是牛羊以粗饲料作为主要食物的原因之一。很多牛羊非常容易出现前胃疾病,饲养人员要掌握牛羊前胃疾病的预防办法和治疗措施。     

GHSR—1a在奶山羊胃肠道的分布与表达

试验采用免疫组织化学、Real—timePCR和Western blotting方法测定ghrelin的功能性受体GHSR-1a（Growth hormone seeretagogue receptor-1a,GHSR-1a）在奶山羊胃肠道的分布和表达。免疫组织化学结果显示,GHSR—1a免疫阳性细胞广泛分布于奶山羊胃肠道。在皱胃主要定位于黏膜层和肌层;瘤胃、网胃和瓣胃黏膜层及肌层中也可见GHSR-1a免疫阳性细胞;在小肠主要位于十二指肠、空肠和回肠的黏膜层、黏膜下层和肌层;在结肠、盲肠和直肠GHSR—1a免疫阳性细胞也有广泛分布;GHSR—1a主要表达于内在神经丛神经细胞、胃底腺上皮细胞、肠腺上皮细胞、复层鳞状上皮细胞、平滑肌细胞中。real—timePCR和Westernblotting结果显示,皱胃、十二指肠、空肠、回肠、盲肠、结肠和直肠GHSR—1a的表达水平相对较高,显著高于瘤胃、网胃和瓣胃的表达（P〈0．05）。结果表明,ghrelin可能通过GHsR-1a对奶山羊胃肠功能具有重要的调节作用。     

Prenatal histomorphological development of the reticulum in fallow deer (Dama dama)

The histomorphological changes occurring in the Dama dama reticulum during prenatal development have been investigated. Twenty‐five Dama dama embryos were used, from the first stages of prenatal life until birth. Differentiation of the reticulum was observed at 23% gestation. By 25% gestation the reticular wall comprised three layers: an internal epithelial layer, a middle layer of pluripotential blastemic tissue and an external layer or serosa. Primary reticular crests were visible at 38% gestation. Secondary reticular crests were observed at 61% gestation. Neuroendocrine cells were detected by synaptophysin (SYP) at 35% gestation, in the lamina propria‐submucosa, tunica muscularis, and serosa. Epithelial Cytokeratin‐18 (CK‐18) cells were observed at 35% gestation extended throughout the epithelial layers. The glial cells (vimentin –VIM‐ and glial fibrillary acidic protein‐GFAP‐markers) were discerned at 25% and 43% gestation, respectively, in myenteric and submucosal plexuses, lamina propria, muscularis mucosae, tunica muscularis, and perivascular connective tissue. The neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) markers were immunodetected at 75% and 80 gestation, respectively, in the lamina propria‐submucosa, muscularis mucosae, tunica muscularis, serosa, and myenteric plexuses. The prenatal development of the fallow deer reticular mucosa evidenced a considerable precocity similar to that previously reported in goat and red deer.     

Calcium-Binding Proteins and Neurotransmitters in the Stomach Myenteric Plexus of the Korean Native Goat

The expression of calbindin D-28k (CB), calretinin (CR), substance P (SP) and calcitonin gene-related peptide (CGRP) in the stomach myenteric plexus of the Korean native goat stomach was investigated by immunohistochemistry. The results demonstrated the presence of nerve fibers and cell bodies immunoreactive (IR) to CB, CR, SP and CGRP. In tissues of rumen, reticulum, omasum and abomasum, some distinct neuronal populations could be distinguished according to their morphologic and neuronal chemical properties: Dogiel type I cells which have irregular lamellar dendrites and a single axon, Dogiel type II cells which have large ovoid cell bodies and several long axon-like processes, and small filamentous interneurons. CB-, CR-, SP- and CGRP-IR neurons and fibers were observed in the myenteric plexus of stomach, and varicose nerve fiber immunostained to SP and CGRP also were found in the muscle layer. In myenteric plexus of the stomach, CB- and SP-positive neurons were characterized by Dogiel type II and CR-IR neurons were classified Dogiel type I with lamellar dendrites, and immunoreactivity of CGRP was very weak in the somata. SP- and CGRP-IR nerve fibers formed dense networks within the myenteric ganglia. SP-IR cell bodies and their fibers were found in the myenteric plexus, and the immunoreactivity and number of cell bodies were more than CB-, CR-, and CGRP-IR neurons. These results suggest that SP, CGRP, CB and CR in the myenteric neurons of Korean native goat stomach may have play an important role in the dynamic movement.
(Support contributed by: Korean Research Foundation 2003-015-E00195).     

A comparative study of the thickness of the tunica muscularis in the forestomach and abomasum of grey, white and black Karakul lambs.

Homozygous grey Karakul lambs are born with a lethal genetic factor responsible for death and weaning age. When put on a high roughage diet under field conditions they develop distended, thin-walled rumens and sand impacted abomasa. Homozygous white Karakul lambs have a similar factor but survive for a longer period. Black Karakul lambs are not affected. The present study was undertaken to compare by image analysis the thickness of the tunica muscularis of the forestomach and abomasum of 24-hour old grey, white and black Karakul lambs. One square centimetre samples were taken from equivalent areas in each case of the rumen, reticulum, omasum and abomasum of 38 embalmed Karakul lambs. Haematoxylin and eosin stained histological sections of each sample were studied with a Vids 2 Image Analyzer and the thickness of the circular and longitudinal muscle layers was measured. An analysis of variance indicated a significant difference between the groups in the thickness of the tunica muscularis of the rumen, reticulum and abomasum; the grey group displaying the thinnest and the black group the thickest. The omasa were not affected. The study indicates a reduction in thickness of the tunica muscularis of the homozygous grey and white lambs when compared to normal black lambs.     

Early organogenesis of the caprine stomach

Early organogenesis of the caprine stomach was studied in a series of 11 embryos ranging from 6.5 mm neck-rump length (NRL) to 13.3 mm crown-rump length (CRL). In embryos with 6.5-6.7 mm NRL, a part of the primordial proper esophagus extended to the dorsal side of the primordial stomach. The primordial proper esophagus and its extension were lined with a simple epithelium and stained dark brown with Con A III, while the primordial stomach was weakly stained. In embryo with 7.3 mm NRL, the esophageal extension was separated from the proper esophagus by constriction, and became a primordial forestomach situated in an area outside the omental sac. In embryos with 8.3 mm NRL-10.7 mm CRL, primordial forestomach and primordial stomach were united and formed a spindle shaped primordial ruminant stomach with foregut rotation. The primordial ruminant stomach was similar to the primordial simple stomach except that it was more flattened laterally with the convex at the area of 'lesser curvature'. Primordial rumen, omasum and abomasum appeared from the spindle shaped primordial ruminant stomach in an embryo with 12.9 mm CRL. In an embryo with 13.3 mm CRL, primordial reticulum originated from an area between the primordial rumen and omasum.     

A comparative study of the anatomy of the omasum in domesticated ruminants

The structure of the omasum was compared in 10 water buffalo (Bubalus bubalis), 10 Shorthorn cattle (Bos indicus), 9 Merino sheep (Ovis aries) and 10 cross-bred goats (Capra hircus), and the functional significance of the differences is discussed. The weight of the omasum and area of the internal laminae appeared to be smaller in Brahman cattle than the buffalo and British cattle. When compared in relation to body weight, the omasums of caprid animals were smaller than those of bovids, by a factor of 0.33-0.67 but the omasums of goats were appreciably larger than sheep. The number of laminae ranged from 33 to 35 for the sheep and goats compared with 122 to 169 for the buffalo and cattle. It is suggested that the marked difference in structure of the omasum between the small and large ruminants may influence the food intake of these animals through the effects of this gut compartment on absorption of nutrients and passage of digesta.     

饲用甜高粱和全株玉米青贮对肉羊前胃微生态的影响

本试验旨在探究饲用甜高粱青贮（sweet sorghum silage, SS）和全株玉米青贮（whole-plant corn silage, CS）对肉羊前胃微生态的影响。选择健康的3~4月龄杜泊母羊［（33.40±1.68） kg］14只,随机分为2组,每组7只羊,每只羊为1个重复,分别喂甜高粱青贮（SS组）和玉米青贮（CS组）,单栏饲喂并自由饮水。预饲期15 d,正试期90 d,在正试期测定并计算生长性能指标,正试期结束后,每组选取4只羊进行屠宰,采集前胃（瘤胃、网胃和瓣胃）食糜和组织样品,对前胃发酵参数、微生物表达量、上皮颜色和组织结构进行观察和测定。结果表明：1）CS组肉羊的干物质采食量显著高于SS组（P<0.05）。2）甜高粱青贮和玉米青贮育肥肉羊90 d后,对前胃的pH值未产生显著影响（P>0.05）;在网胃内容物中,SS组肉羊氨氮浓度显著高于CS组（P<0.05）,CS组肉羊丁酸含量显著高于SS组（P<0.05）;SS组肉羊瘤胃总挥发性脂肪酸含量显著高于CS组（P<0.05）。3）SS组肉羊瘤胃内短普雷沃氏菌、栖普雷沃氏菌、产琥珀酸丝状杆菌和黄色瘤胃球菌的表达量显著高于CS组（P<0.05）。4）饲粮处理显著影响前胃颜色,CS组肉羊的前胃上皮颜色比SS组深（P<0.05）。5）SS组肉羊瘤胃乳头宽度显著高于CS组（P<0.05）,饲喂甜高粱青贮和玉米青贮对肉羊网胃黏膜厚度、黏膜下层厚度和肌层厚度并未产生显著影响（P>0.05）,CS组肉羊的瓣胃黏膜上皮厚度显著高于SS组（P<0.05）。综上所述,在本试验条件下,和饲用玉米青贮相比,饲用甜高粱青贮肉羊的采食量较低,且这两种青贮料饲喂对肉羊的微生态有影响,甜高粱青贮组肉羊的瘤胃总挥发性脂肪酸含量、前胃内纤维分解菌的表达量以及瘤胃乳头宽度等指标显著高于玉米青贮组,且甜高粱青贮组肉羊的前胃上皮颜色较浅,角质化程度低,有利于肉羊的胃肠道健康。     

Histomorphometric study of the goat stomach during prenatal development

The aim of this study was to perform a morphometric analysis of the different structural tissue layers of the goat stomach to study their prenatal growth from mathematical models fitted to these morphometric data. A total of 90 embryos and fetuses were used, from the early stages of prenatal life until birth. The growth rate of the gastric wall was slower than that of body length; rumen was the stomach compartment displaying slowest growth. In the three non‐glandular compartments, the epithelial layer grew faster than the gastric wall itself, while the growth rate of the abomasal epithelium declined in the early stages of development. A decline in growth rate was also observed for the lamina propria and submucosa in rumen and reticulum from the early embryonic stages, whereas in omasum and abomasum these layers continued to grow as gestation progressed. The tunica muscularis displayed consistent growth in all compartments, growing faster than the gastric wall. Serosa thickness increased as gestation progressed, displaying a decline in growth‐rate only in the omasum. In conclusion, the dynamics of gastric wall growth were governed by the growth rate of each of the component tissue layers.     

Dry matter and digesta particle size gradients along the goat digestive tract on grass and browse diets

Physical properties of the digesta vary along the ruminant digestive tract. They also vary within the forestomach, leading to varying degrees of rumen contents stratification in ‘moose‐type’ (browsing) and ‘cattle‐type’ (intermediate and grazing) ruminants. We investigated the dry matter concentration (DM) and the mean digesta particle size (MPS) within the forestomach and along the digestive tract in 10 goats fed grass hay or dried browse after a standardized 12‐h fast, euthanasia and freezing in the natural position. In all animals, irrespective of diet, DM showed a peak in the omasum and an increase from caecum via colon towards the faeces and a decrease in MPS between the reticulum and the omasum. Both patterns are typical for ruminants in general. In the forestomach, there was little systematic difference between more cranial and more caudal locations (‘horizontal stratification’), with the possible exception of large particle segregation in the dorsal rumen blindsac on the grass diet. In contrast, the typical (vertical) contents stratification was evident for DM (with drier contents dorsally) and, to a lower degree, for MPS (with larger particles dorsally). Although evident in both groups, this stratification was more pronounced on the grass diet. The results support the interpretation that differences in rumen contents stratification between ruminants are mainly an effect of species‐specific physiology, but can be enhanced due to the diet consumed.     

Comparative analysis of the merino sheep and Iberian red deer abomasum during prenatal development

The aim of this study is to describe differences in the ontogenesis of the abomasum in sheep (domestic ruminant) and deer (wild ruminant). Histomorphometric and immunohistochemical analysis were carried out on 50 embryos and fetuses of the sheep and 50 red deer from the first prenatal stages until birth. To compare similar periods of gestation in both species, we calculate the percentages of gestation. The appearance of the abomasum was earlier in the red deer (22% gestation) than in the sheep (25% gestation). Throughout development the epithelium happened sequentially, being of the types pseudostratified to simple cylindrical. This important modification was earlier in the red deer than the sheep. At 46% gestation in red deer and 50% in sheep, gastric pits were observed on the surface of abomasal folds. Our studies suggest a close link between the initial formation of these pseudoglandular structures and the clear separation of lamina propria and submucosa separated by de muscularis mucosae. At 54% gestation in red deer and at 60% in sheep, in the bottom of these pits the first outlines of glands were distinguishable. Finally, the presence of neuroendocrine and glial cells were detected in deer at earlier stages than in sheep.     

Physical characteristics of gastrointestinal content of llama (Lama glama)

Changes in digesta dry matter (DM) and mean digesta particle size (MPS) along the gastrointestinal tract are well known in ruminants, but not in camelids. We collected digesta from the dorsal (d) and ventral (v) first forestomach compartment (C1), the second forestomach compartment (C2), three proximal segments and the subsequent glandular part of the third compartment (C3A‐D), the caecum and the faeces twelve llamas (Lama glama). DM analysis indicates the presence of digesta stratification in the C1, the presence of fluid in the C2 to facilitate the sorting function of this compartment, the fluid‐absorbing function of the proximal parts of the C3, the secretion of enzymes and digestive acids in the C3D, and the water‐resorbing function of the lower intestinal tract. These findings illustrate the functional resemblance between the gastrointestinal tract of camelids and cattle‐like ruminants (C1 equivalent to the rumen with stratified contents, C2 to the reticulum, C3A/B/C to the omasum and C3D to the abomasum). MPS analysis revealed a progressive reduction in MPS from the C1 to the distal C3. This gradual transition is different from the clear‐cut threshold in ruminants between the reticulum and the omasum and had so far only been described in dromedaries (Camelus dromedarius). These findings indicate that regardless of the convergent property of rumination and resemblance of general mechanisms involved in contents stratification and particle sorting, differences between ruminants and camelids exist that could be interpreted as a more efficient functionality of the ruminant forestomach.