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1.
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.  相似文献   

2.
The muscularis mucosae and condensed fibrous layer of the ruminant forestomach were studied by immunohistochemistry using specific antibodies against alpha-smooth muscle actin (alphaSMA) and gamma-smooth muscle actin (gammaSMA). The specimens were collected from the rumen, reticulum and omasum of cattle, water buffalo, sheep, goat, Barbary sheep, Japanese serow, sika deer and mouse deer. The muscularis mucosae showed immunoreactivity for both alphaSMA and gammaSMA. On the other hand, the condensed fibrous layer appearing between the propria mucosa and tela submucosa was immunoreactive only for alphaSMA except for that in the goat and Barbary sheep reticulum which is intermingled with gammaSMA immunoreactivity. The distribution of muscularis mucosae and/or condensed fibrous layer varied among the compartments of forestomach and ruminant species. In the rumen, only the condensed fibrous layer was detected. On the other hand, the omasum contained only the muscularis mucosae. In the reticulum, both were detected. The amount of the condensed fibrous layer in the reticulum varied among different species in the following order of abundance: goat > Barbary sheep > sika deer> sheep > water buffalo > cattle and Japanese serow. Smooth muscle cells of external muscle layer were immunoreactive for alphaSMA and gammaSMA whereas those of blood vessels and pericytes were immunoreactive only for alphaSMA. The present findings on the actin immunoreactivity and distribution profile of muscularis mucosae and the condensed fibrous layer provide additional knowledge to further understand the histophysiological specialization of the different compartments of the ruminant forestomach.  相似文献   

3.
Light microscopic observations revealed that in camel foetuses of 25 mm crown-to-rump length (CRL) the primordial tubular system of the prospective lung was formed of several tubules lined by undifferentiated columnar epithelium. Intra-epithelial neuroendocrine cells were the first elements to be differentiated in the lining epithelium of the primordial tubular system of the prospective lung as early as 25 mm CRL. On reaching 50–67 mm CRL, the primordial tubular system started to differentiate into two systems of primordial tubules, the prospective bronchial or light tubules and the future respiratory or dark tubules. The lining epithelium of the prospective bronchial tubules revealed a clear evidence of ciliogenesis as early as 80 mm CRL. From 800 mm CRL onwards, the bronchial epithelium demonstrated ciliated and non-ciliated secretory cells. The non-ciliated secretory cells of the bronchial epithelium of fetal camel lung showed moderate reaction to AB/PAS technique, for the first time, in fetuses reaching 600 mm CRL.  相似文献   

4.
Light microscopic observations revealed that in camel foetuses of 25 mm crown‐to‐rump length (CRL) the primordial tubular system of the prospective lung was formed of several tubules lined by undifferentiated columnar epithelium. Intra‐epithelial neuroendocrine cells were the first elements to be differentiated in the lining epithelium of the primordial tubular system of the prospective lung as early as 25 mm CRL. On reaching 50–67 mm CRL, the primordial tubular system started to differentiate into two systems of primordial tubules, the prospective bronchial or light tubules and the future respiratory or dark tubules. The lining epithelium of the prospective bronchial tubules revealed a clear evidence of ciliogenesis as early as 80 mm CRL. From 800 mm CRL onwards, the bronchial epithelium demonstrated ciliated and non‐ciliated secretory cells. The non‐ciliated secretory cells of the bronchial epithelium of fetal camel lung showed moderate reaction to AB/PAS technique, for the first time, in fetuses reaching 600 mm CRL.  相似文献   

5.
Mathematical models describing the histomorphometric growth of ruminant stomach during prenatal life One hundred forty four ovine embryos and feti were used in an investigation to determine mathematical models describing the histomorphometric growth of tissues and compartments of the ruminant stomach. The results indicate that during prenatal life the diameter of the gastric chambers increase more slowly than the length. The tissue layers of the gastric walls, particularly the muscular tunic of all compartments demonstrated a uniform tendency toward more rapid development than the compartment walls proper.  相似文献   

6.
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.  相似文献   

7.
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.  相似文献   

8.
The development of the parotid gland was examined in 36 bovine embryos and foetuses with a crown-rump-length (CRL) from 28 up to 1000 mm by light, transmission electron microscopical and actin-immunohistochemical methods. The anlage of the parotid gland in an embryo with 28 mm CRL can be found at the lateral angle of the primitive oral cavity as a local thickening of the epithelium. During the second month, the differentiation of primary ducts and endbuds starts and a lumen develops in the primary ducts. At the end of the second month a lumen appears in the terminal endbuds. In the immature endpiece cells first secretory granules can be seen from a CRL of 240 mm. In the third month differentiation between intra- and inter-lobular ducts is possible. Immature myoepithelial cells present as a basal layer of flattened cells between the epithelial cells and the basement membrane at the end of the second month. During further development they increase in number, become more flattened and form long cellular processes. At the end of the fourth month isolated actin filament bundles are formed, which were also detected by an antibody against smooth muscle actin. The actin filaments condense continuously until they fill the cell processes completely at the end of foetal development.  相似文献   

9.
Yolk sac development was investigated in 69 ovine and 10 bovine embryos from the blastocyst stage to the 7th week of gestation. Light and electron microscopical findings are reported. The yolk sac in sheep and cattle is composed of an enlarged sac-like portion lying below the embryo and two ends which follow the elongated course of the trophoblast. In sheep, an open connection exists between the intestines and the yolk sac up to a crown-rump length (CRL) of 9 mm. It is closed by 12 mm CRL. The wall of the yolk sac is especially well vascularized in the enlarged, sac-like portion. Primary erythropoiesis occurs within the blood capillaries. In the blastocyst, the yolk sac entoderm is made up of elongated, flat cells. It becomes cuboidal in the 3 mm embryo (ovine) and later columnar. The up to 20 microns tall cells stain darkly and contain numerous light-colored vesicles. At 4.5 mm CRL light cells appear between the dark ones. Both cells are rich in rough endoplasmic reticulum (rER). The increased staining of the darker cells is due to an osmophilic cytoplasm and numerous, often parallel lamella of rER. The rER of the light cells is enlarged to irregularly-shaped cisternae, which nearly fill the entire cytoplasm and give them a rounded appearance. The dark cells contain polygonal nuclei, whereas those in the light cells are round with one or two nucleoli. The oval mitochondria have only a few peripheral cristae. Golgi fields are not very common. Cells of the entoderm are connected to one another over zonulae occludentes. They possess microvilli on the luminal surface and are supported by a basement membrane. From 5 mm CRL onwards (ovine), the yolk sac entoderm folds itself between the capillaries, thereby becoming stratified. The intercellular space between the cells expands as projections between neighboring cells interlock. Canaliculi arise between adjacent epithelia. The wall of the yolk sac thickens as a result of this infolding and the densely packed capillaries. Infoldings are especially predominant in the sac-like portion of the yolk sac, and only suggested in the ends. Involution of the yolk sac begins in the peripheral end segments and proceeds centripetally. Numerous glycogen particles appear in the yolk sac entoderm cells of the ovine fetus at a CRL of 36 mm, and by a CRL of 42 mm, the sac-like portion has also begun to show signs of degeneration. Mesenchyme is very sparse within the wall of the yolk sac throughout the entire period of development.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

10.
牛瘤胃积食又被称为瘤胃急性扩张,是牛养殖中最易发生流行的一种胃部疾病,主要是因为大量的纤维饲料或者易产生气体的膨胀饲料堆积在瘤胃中,不能正常向下运转,造成瘤胃容积显著扩大,内容物长期停滞发酵产生酸性物质,影响前胃机能,形成脱水和酸中毒的一种疾病。在牛养殖中,需要对饮食和饲养管理进行严格的要求,确保整个养殖环境清洁卫生,有效防止牛异食癖引发瘤胃积食的发生,保证牛健康生长。该文主要论述牛瘤胃积食的发病原因、临床症状和防治措施。  相似文献   

11.
反刍动物的胃是复胃,与单胃动物的胃不同。反刍动物主要以瘤胃中发酵产生的短链脂肪酸(SCFA)作为机体的能量物质,而绝大部分的SCFA又通过瘤胃上皮直接吸收,为宿主供能。因此,深入了解瘤胃上皮结构特点有助于对其吸收功能进行深入的研究。笔者主要对瘤胃上皮的解剖学特点、细胞学特点及超微结构进行了综述。  相似文献   

12.
The hypotheses for the development of the omental bursa (rotation of the stomach, formation of folds, invagination of the celomic epithelium, formation of a recess) do not agree with each other. On 31 sheep embryos (4–50 mm CRL; 16–44 days old) the formation of the omental bursa was studied using serial sections and three-dimensional reconstructions. The primary epiploic foramen induces fusion and enlargement of mesenchymal clefts on the right side of the foregut, producing recesses. The latter, after elongation of the dorsal and ventral mesogastria, give rise to the omental bursae.  相似文献   

13.
0~56日龄放牧羔羊消化道的解剖特点和瘤胃功能变化   总被引:4,自引:2,他引:2  
旨在研究完全放牧条件下羔羊消化道相对质量与相对容积和瘤胃功能的发育特点。选用44只甘肃高山细毛羊公羔,测定0、3、7、14、21、28、42与56日龄胃(前胃、皱胃)、小肠各段和盲肠的相对质量(%活体质量),胃各室相对质量(%全胃质量)、相对容积(%全胃容积)、内容物相对质量(%全胃内容物质量)及瘤胃内容物微生物酶活性和挥发性脂肪酸(VFA)的浓度。结果表明:前胃、小肠、盲肠相对质量随羔羊日龄增大而提高,14~21d前胃与盲肠相对质量增速最快,其次为42~56d;小肠相对质量各阶段增速波动较小。随日龄增长,瘤胃相对质量与相对容积升高,皱胃相应下降,7~14、14~21与42~56d变速较大;0~14d前胃相对容积增速低于相对质量,14d后其增速快于后者,28d后相对容积增速大于相对质量。胃各室内容物的pH相对稳定,瘤胃内容物pH变动于6.03~6.67;0、3、7d部分受试羔羊中被检出纤维素酶比活性的比例随日龄增大,14d后所有受试羔羊均被检出,且纤维素酶比活性随日龄增高。14d蛋白酶活性最高,42d淀粉酶、纤维素酶比活性最高;从3d羔羊瘤胃内容物中即检出乙酸、丙酸、丁酸,其浓度均随日龄增大而升高,VFAs浓度与微生物酶比活性峰值的出现与瘤网胃发育状况并行。结论:羔羊前胃相对质量0~21d增长较快,而此后其增速减慢,是羔羊营养状况改变引起的;本试验条件下,羔羊2月龄断奶较适宜,42d是可接受的最早断奶日龄。  相似文献   

14.
将腹腔镜从山羊胸骨柄后缘的腹中线插入腹腔,观察山羊在仰卧状态下瘤胃、网胃、瓣胃和皱胃,以及它们与肝脏、膈肌、腹壁和肠管的位置关系,并获得清晰的图片,为诊断和治疗反刍动物胃部疾病提供依据。  相似文献   

15.
The most significant focal points of the embryo transfer technology are as follows: the selection of donors, the response of the selected donor to the superovulation protocol and the obtained number of the transferable embryos. For this purpose, it is suggested that donor selection can be done by anti‐Müllerian hormone (AMH) levels, and embryo production is evaluated. AMH is secreted by the granulosa cells of primordial, pre‐antral and antral follicles below 4 mm in the ovary, independent of FSH. Therefore, the aim of this study was to investigate the relationship between serum AMH levels and the number of corpus luteum (CL), total embryos and transferable embryos that were shaped after a uniform superovulation protocol. For this reason, 48 Simmental cows, which were located at General Directory of Agricultural Enterprises (region, province, etc. instead of the general directorate), were used as donors for the embryo transfer. Blood samples were taken at random, regardless of the stage of animal's sexual cycle. AMH levels were measured by enzyme‐linked fluorescent assay (ELFA) method of the miniVIDAS® (bioMérieux SA) using AMH Bovine Test Kit. According to the statistical analyses of the obtained data, AMH levels were positively correlated with CL and total embryos (p < .05). No significant correlations between AMH and transferable embryos were approved (p > .05). It was also determined that each 200 pg/ml increase in serum AMH level resulted in one increase in CL number. Overall, considering the positive correlation between AMH level and the obtained number of CL and total embryos after a superovulation treatment, it was concluded that measuring blood AMH level prior to any further costly implementation may be an effective method in donor selection.  相似文献   

16.
B族维生素在瘤胃中的合成及影响因素   总被引:1,自引:0,他引:1  
反刍动物经典理论认为瘤胃中合成的B族维生素能满足其营养需要,然而最近研究表明,在一些情况下反刍动物需要在日粮中添加B族维生素。本文就瘤胃中B族维生素的合成和瘤胃中B族维生素的来源、分布、吸收及合成的影响因素进行了回顾和综述,为进一步深入开展反刍动物B族维生素营养研究提供理论基础。  相似文献   

17.
Uri  Bargai  AB  VMD  DVSc.  Ami Tsvi  Nathan  DVM  Shmuel  Pearl  DVM 《Veterinary radiology & ultrasound》1991,32(5):259-260
An 18-month-old pregnant heifer, hitherto normal, was noticed to regurgitate wet, partially digested roughage several times a day. On clinical examination, the heifer was losing body weight. There was no obstacle to passing a stomach tube to the rumen. A barium study of the esophagus was performed. Megaesophagus involving the cervical and cranial thoracic esophagus was diagnosed. Postmortem findings were a dilated esophagus, with no gross pathology seen. Histopathology showed extensive submucosal cellular infiltration of eosinophils. The classification and possible etilogy of the case is discussed.  相似文献   

18.
Based upon macroscopic and light microscopic examinations the development of the superior colliculus of bovine embryos and fetuses with crown-rump lengths (CRL) ranging from 0.8 to 90.0 cm was studied. Macroscopically, the mesencephalon can be recognized for the first time at 0.8 cm CRL, whereas the superior colliculus can be clearly differentiated in embryos of 4.5 cm CRL. The macroscopic features of this brain area have reached adult conditions at 80.0 cm CRL. The light microscopic examination reflected the beginning of layer formation at 0.8 cm CRL, which is induced by the proliferating activity of the ventricular zone. Up to 3.4 cm CRL the primordium of the tectum opticum exhibits still a trilaminate pattern (ventricular-, intermediate- and marginal zone), but at 4.5 cm CRL, the formation of the specific tectal layers is marked by the origin of the stratum profundum and intermedium. With the appearance of the tenth layer named stratum opticum at 8.0 cm CRL the laminar pattern corresponds to the characteristics of adult animals.  相似文献   

19.
碳水化合物在优化反刍动物瘤胃发酵,提高饲料利用效率,进而提高动物的生产性能等方面具有极其重要的作用。作者从碳水化合物的需要量的生理机制,农副产品应用及其对反刍动物生产性能、繁殖性能和产品品质影响等方面对反刍动物碳水化合物营养研究进行了综述。  相似文献   

20.
Origin of abomasum gas in the cows with displaced abomasum   总被引:2,自引:0,他引:2  
The gas composition of the rumen and the abomasum were investigated in 71 cows including 25 cows with displaced abomasum. The ratio of methane (CH4) to CO2 in the abomasum gas was higher than that in the rumen. In the incubated mixtures of fresh rumen fluid, CH4 was detected at a high concentration, while a small amount of CO2 and CH4 was found in incubated mixtures of fresh abomasum fluids. Hence, it was suggested that the gas in the abomasum originated not from the abomasum itself but from the rumen. In cows fed with mixed roughages and concentrates, the rumen CO2:CH4 ratio was higher compared with cows fed with roughages alone. Marked changes in rumen gas composition were presumed to be associated with changes in abomasum gas composition. Consequently, it is possible that feeding a large quantity of concentrates may increase the flow rate of the ingesta through the forestomach, so that the return rate of gas separated from the ingesta in the abomasum to the forestomach may also increase. Therefore, the frequent accumulation of a large amount of gas with concomitant changes in the total volatile fatty acid (VFA) concentration in the abomasum caused abomasal atony and subsequently displaced abomasum.  相似文献   

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