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.     

反刍动物胃溶菌酶的研究进展

反刍动物胃溶菌酶与其他溶菌酶相比,能在其他溶菌酶无活性或活性较低的胃中(含有胃蛋白酶和胃酸)保持较高的溶菌能力。作者从反刍动物胃溶菌酶的理化性质、酶活性影响因素、进化等方面综合介绍了反刍动物胃溶菌酶的部分特性,并对其应用前景作出展望。     

Micromorphological Studies on the Stomach of Sheep during Prenatal Life

17 Merino and Blackface sheep foetuses were used in a study of the development of the ovine foetal stomach. The histogenesis of each compartment of the stomach during the period from the 26th to the 130th day of prenatal life was described.     

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.     

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.     

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.     

Anatomía del Desarrollo del Tracto Digestivo y Forma Corporal Externa Durante el Período Embrionario en el Caprino (Copra hircus)

Anatomy of the digestive tract and external body development during the embryonic stages of the caprine (Copra, bircus) The purpose of this work has been to establish the pattern of prenatal growth and normal development of the digestive tract and annex glands during goat embryonic stages. 21 embryos with ages ranging from 14 to 34 days (1.69 to 5.90 cm CR) as determined by registering the mating time, were obtained by cesarea. This material was histologically processed to obtain complete serial sections of the stomatodaeum, foregut, midgut, hindgut and cloaca. In this work, it is chronologically described the morphogenesis and histogenesis of the mouth, hypophysis, pharynx and its derivatives, stomach, intestine, liver, pancreas and cloaca. The results obtained establish chronological comparisons with the development of the lamb and gives information on the unitary origin of the gastric compartments in ruminants.     

A microscopical examination of the gastric morphology of the white-tailed rat Mystromys albicaudatus (Smith 1834)

A study of the gastric morphology of Mystromys albicaudatus revealed a sacculated stomach with a papillated, keratinized corpus separated from a distal glandular antrum by a ρ re- gastric pouch. Gastric morphology of this type is defined as bilocular hemiglandular. Although the forestomach of M. albicaudatus bears a superficial resemblance to that of a ruminant, the corpus (and papillae in particular) differ structurally and functionally from the rumen. Whereas rumen papillae are important in absorption, those of M. albicaudatus increase surface area for the attachment of symbiotic bacteria.     

Nuclear imaging of the stomach of healthy dogs.

To evaluate the use of technetium pertechnetate (99mTcO4) as a means of estimating gastric mucosal integrity, nuclear images of the empty stomach were obtained from 6 dogs at 20, 40, 60, 120, 180, and 240 minutes after IV administration of the radiopharmaceutical. Blood and gastric secretion samples were collected during the same time intervals. The left lateral-view image of the stomach was used to calculate the relative fraction of the dose in the stomach and the count density ratio. Between 20 and 40 minutes and 40 and 60 minutes, significant differences (P less than 0.001) were apparent in the amount of 99mTcO4 in the stomach. Blood concentration of 99mTcO4 decreased significantly (P less than 0.001), whereas gastric secretion concentration increased significantly (P less than 0.001) over time. Qualitative assessment of the gastric nuclear scans and the statistical analytic results indicated that the optimal time for imaging the canine stomach was between 40 and 60 minutes after radiopharmaceutical administration. In a second study, the same dogs were pretreated with the H2-receptor antagonist cimetidine and the cholinergic antagonist glycopyrrolate to block gastric secretions. Over time, changes in the relative dose fraction in the stomach and the density ratio were the same as values obtained during the experiment performed without use of cimetidine and glycopyrrolate. Results of the study indicate that nuclear imaging with 99mTcO4 outlines normal canine gastric mucosa and that pretreatment with cimetidine and glycopyrrolate has no effect on the quality of the gastric image.     

牛前胃驰缓发病原因及防治对策

牛是特殊的反刍类动物,在生长发育阶段与其他动物养殖有较大的差别,一旦养殖管理不当,易造成胃部疾病的发生,其中前胃驰缓是很易发生的一类胃部疾病。该疾病虽然不是传染性疾病,不会造成严重的死亡,但是会影响牛的正常生长发育。该文主要论述牛前胃驰缓的发病原因和具体的防治对策。     

Ontogenesis of the rumen: A comparative analysis of the Merino sheep and Iberian red deer

The aim of this study is to describe differences in the ontogenesis of the rumen in the sheep (domestic ruminant) and deer (wild ruminant). A total of 50 embryos and fetuses of Merino sheep and 50 of Iberian deer were used, from the first stages of prenatal life until birth. For the study, the animals were divided into five experimental groups according to the most relevant histological characteristics. The appearance of the rumen from the primitive gastric tube was earlier in the sheep (22% gestation, 33 days) than in the deer (25% gestation, 66 days). In both cases it displayed a primitive epithelium of a stratified, cylindrical, non‐ciliary type. At around 28% gestation in the sheep (42 days) and 26% (67 days) in the deer, the rumen was configured of three clearly‐differentiated layers: internal or mucosal, middle or muscular and external or serosal. In both species the stratification of the epithelial layer was accompanied by modifications in its structure with the appearance of the ruminal pillars and papillae. The pillars appeared before the papillae and the appearance of both structures was always earlier in the deer (pillars: 70 days, 27% gestation; papillae: 97 days, 36% gestation) than in the sheep (pillars: 42 days, 28% gestation; papillae: 57 days, 38% gestation). The outlines of the ruminal papillae appeared as evaginations of the basal zone toward the ruminal lumen, dragging in their formation the basal membrane, the lamina propria and the submucosa. The tegumentary mucosa of the rumen was without secretion capability in the first embryonic phases. From 67 days (26% gestation) the neutral mucopolysaccharides appeared in the deer and at 46 days (30% gestation) in the sheep. In both cases they continued to decrease until birth, this diminution being more pronounced in the deer. Finally, the presence of neuroendocrine and glial cells was detected in the deer at earlier stages than in the sheep.     

日粮蛋白质和中性洗涤纤维水平对幼龄反刍动物生长发育影响的研究进展

幼龄阶段是反刍动物生长中非常重要的阶段,这一时期的营养供应、生长发育状况和瘤胃发育程度决定了其成年后的生产性能和繁殖效率。由于幼龄阶段消化代谢系统发育不完善且具有极强的可塑性,此阶段日粮的营养水平,尤其是蛋白质和中性洗涤纤维（NDF）水平,在反刍动物发育过程中发挥着非常重要的作用。在生产实践中,营养供给不足或超量供给都会影响幼畜的生长发育及健康状况,这种情况甚至会伴随其一生。而幼龄反刍动物日粮中蛋白质和纤维水平对生长性能和胃肠道发育的调节具有决定性的作用。适量提高日粮中蛋白质水平,可提高幼龄反刍动物的生长发育程度,并由于饲料中瘤胃微生物可利用氮浓度的提高而提高了营养物质消化率和瘤胃的发育。在保证精饲料充足的情况下,提高日粮中NDF水平可提高幼龄反刍动物开食料的采食量,提高生长性能和促进瘤胃发育,同时也伴随着营养物质消化率的提高。但由于试验动物或原料来源不同,在相关试验中仍存在不同的试验结果。为此,作者针对日粮中不同蛋白质和NDF水平对幼龄反刍动物生长发育、营养物质消化率和瘤胃发育的影响,以及出现不同试验结果的原因进行总结和探讨,以期为解决幼龄反刍动物的饲养管理问题、提高其饲养效率提供理论依据。     

Immunohistochemical study of the ontogeny of prochymosin--and pepsinogen-producing cells in the abomasum of sheep

The appearance and development of prochymosin- and pepsinogen-producing cells were investigated in the ovine abomasum from fetus to adult using immunohistochemistry. Prochymosin immunoreactivity appeared first in the proper gastric glands of the 100-day-old fetus. The intensity and distribution of prochymosin-immunoreactive cells increased gradually with the progress of gestation, and their most intense immunoreactivities and widest distribution were observed in 3-day-old lambs. They were subsequently reduced throughout postnatal growth. A few prochymosin-immunoreactive cells were scattered in the glands of adult sheep. Pepsinogen immunoreactivity appeared at first in a small number of cells in the base of some proper gastric glands of 120-day-old fetuses. After 130 days, pepsinogen-immunoreactive cells increased their staining intensities and distribution. They reached a peak in area at 21 days, which is comparable to adult sheep. In the pyloric glands, prochymosin- and pepsinogen-immunoreactive cells appeared from 100 and 130 days, respectively. Numbers were reduced in comparison to gastric glands and their occurrence was capricious. The results demonstrated that the ontogeny of prochymosin- and pepsinogen-immunoreactive cells in the abomasum of sheep is more similar to that in cattle than to that in the goat. The present data will contribute to the overall understanding of the development of ruminant gastric proteases.     

Intrinsic Innervation of the Stomach of the Fetal Pig: an Immunohistochemical Study of VIP-Immunoreactive Nerve Fibres and Cell Bodies

Using an immunohistochemical technique, the presence and distribution of vasoactive intestinal polypeptide (VIP) was investigated in cryostat sections, both tangential and transverse, of the fetal pig's stomach. In all fetuses and in all gastric segments investigated, VIP-like immunoreactive (IR) nerve-cell bodies were seen in all intramural ganglia, and VIP-IR nerve fibres were found in all layers of the gastric wall except the tunica serosa. Consequently, VIP-IR nerve fibres were found to form a periglandular network, to accompany arterioles, to interconnect the intramural ganglia, to encircle both VIP-IR-negative and -positive neurons, and were found in all muscle layers. Despite the fact that VIP-IR seems to be restricted to the intramural nervous elements, some nonspecific-reacting VIP-IR glandular cells were noticed in the basal parts of the fundic, antral and pyloric gastric glands. The distribution pattern of VIP in the fetal pig resembles that of the adult pig. This suggests a possible functional role for VIP during fetal life and/or puts forward the suggestion that the stomach of a fetal pig from the second half of the gestation period is prepared, from then on, for postnatal function. High similarities with regard to the general distribution pattern of VIP in the stomach have also been noted between the fetal pig and humans, proving once more that the fetal pig can serve as a good animal model in several research areas. Finally, the morphological data provided here may, combined with the physiological significance of VIP, contribute to a better insight into the physiopathology of economically important gastro-intestinal disorders in the pig, such as gastric ulceration.     

Effects of various diets on gastric tone in the proximal portion of the stomach of horses

OBJECTIVE: To assess gastric tone in the proximal portion of the stomach in horses during and after ingestion of 4 diets (2 diets of grain and 2 diets of hay). ANIMALS: 6 adult horses. PROCEDURE: A polyester bag with a volume of approximately 1,600 ml was inserted through a gastric cannula into the proximal portion of the stomach of each horse. Internal pressure of the bag was maintained at 2 mm Hg by use of an electronic barostat, and changes in bag volume were recorded before, during, and after horses consumed diets of grain or hay. Each horse was fed 0.5 and 1.0 g of grain/kg and 0.5 and 1.0 g of hay/kg. Changes in bag volume measured by use of the barostat were indirectly related to changes in tone of the gastric wall. RESULTS: Food intake caused a distinctly significant biphasic increase in volume. The first phase was during active ingestion, which was followed shortly by a second, more prolonged postprandial phase. The ingestion-related phase of the response to intake of a diet of 1 g of hay/kg was significantly greater than that for the other diets. CONCLUSIONS AND CLINICAL RELEVANCE: ingestion of a solid meal induces a biphasic relaxation response in the proximal portion of the stomach of horses. Magnitude of the ingestion-related phase may be determined by size of the meal.     

饲用酶制剂在反刍动物营养中的应用进展

一般情况下,在瘤胃中粗饲料细胞壁组分的消化利用率较低,由于其复杂紧密的结构限制了动物对粗饲料的利用。因此,在反刍动物生产中提高粗饲料利用率的应用研究是非常必要的,不仅改善饲料利用率、提高动物生产性能,还为饲料资源的开发与利用乃至为畜牧业发展提供有效途径。而饲用酶制剂以其绿色、环保、安全等特点成为了该研究领域的热点。通常采用体外和半体内法评定酶制剂处理对粗饲料体外发酵和瘤胃降解特性的影响,并采用体内法评价酶制剂在反刍动物营养中的应用效果。研究表明,外源酶制剂的应用能够有效提高饲料消化率、奶牛产量、肉牛增重和肉羊增重,但其效果不一致,其效果受很多因素的影响,包括酶种类、酶活性、饲粮组成、添加水平、添加方式、动物种类及生长性能等。另外,由于人们对所用酶产品的生化特性掌握不足,导致了对其作用机理、优化条件及影响其作用效果因子的了解不够充分。如酶活性作为酶制剂最主要的生化特性,在使用前往往被忽略检测,并且目前国内外对酶活性的检测及质量评定还没有统一的标准。然而研究结果间直接进行比较也是不科学不合理的。本研究主要从饲用酶制剂的发展历程,反刍动物营养中纤维降解酶的作用机理、应用效果和影响其作用效果的因素以及存在问题等方面进行了综述,旨在为饲用酶制剂在反刍动物营养中的应用提供系统的科学知识。     

Learning Through Foraging Consequences: A Mechanism of Feeding Niche Separation in Sympatric Ruminants

Explanations for why sympatric ruminant species select diets composed of different plant species or plant parts have been controversial. Our explanation is based on learning from foraging consequences, which includes the influences that morphology, physiology, and experience have on diet selection. We conducted a trial with cattle (Bos taurus), sheep (Ovis aries), and goats (Capra hircus) and leafy spurge (LS; Euphorbia esula L.) to explore the interface between the learning and morphophysiological foraging models with these sympatric ruminants. After a pretrial adjustment period, the control group for each species received, via stomach tube on days 1 and 2, ground grass after eating a novel food (NF; rolled corn), and the treatment group for each species received ground air-dried LS after eating the NF. NF intake on days 2 and 3 was expressed as a percent of NF intake on day 1, and it declined considerably for cattle and sheep dosed with LS but did not decline for goats receiving it (P = 0.001). LS elicited learned aversive feeding responses from cattle and sheep but not from goats. The results are consistent with field observations that goats graze LS more readily than sheep or cattle do. Learning from foraging consequences offers an explanation for the unique diets of sympatric ruminant species.     

白三叶无性系植物种群生长模型的研究

文章描述了白三叶无性系植物种群的生长模型。确定性模型不能用于描述白三叶的生长过程，扩散模型和相关走动模型与白三叶的生长过程中一致的，生长在资源丰富的环境中，无性系适合相关随机走动模型，生长在贫瘠环境中，无性系适合散模型。     

A study of 31 cases of gastric carcinoma in dogs

Over a five year period 31 dogs were diagnosed as having advanced gastric carcinoma. The most frequent clinical features were vomiting, polydipsia and weight loss. A predisposition to the tumour was found in the rough collie and Staffordshire bull terrier. In 18 dogs the main finding endoscopically was a large deep ulcer with thickened, irregular rims and walls. Fluoroscopically a marked irregularity of the mucosal surface was noted in 10 dogs. Pathologically, large ulcers with thickening of the stomach wall and involvement of the serosal lymphatics were evident in 17 dogs, and similar ulcers with involvement of the gastric lymph nodes were evident in 18 dogs.     

Vagal reflex inhibition of motility in the abomasal body of sheep by antral and duodenal tension receptors

Vagally-mediated regulation of motility in the abomasal body by duodenal and abomasal antral motility was demonstrated in acutely prepared anaesthetized sheep. The enteric plexuses between the abomasal body, antrum and duodenum were interrupted by transection. Antral contractions were more effective than duodenal contractions at causing inhibition of the abomasal body, and antral isometric conditions were more effective than antral isotonic conditions. Inhibition of motility in the abomasal body was reduced by unilateral cervical vagotomy, was abolished by bilateral cervical vagotomy, and was reversibly inhibited by cervical vagus cold block. The demonstration of vagal pathways in abomaso-abomasal reflexes confirms a functional homology of the mechanisms in the ruminant and animals with simple forms of stomach.Abbreviations b-t balloon-tipped - EMG electromyography - NANC non-adrenergic, non-cholinergic - o-t open-tipped