BACKGROUNDMiniature pig (minipig) is increasingly used as a large animal model for a variety of biomedical studies. Little information is available in the literature on anatomy, histology and sialograghy of the submandibular gland of the minipig. The purpose of this study was to characterize the morphology of a miniature pig's (minipig) submandibular gland as a large animal model for further biomedical studies.

METHODSFive minipigs were subjected to sialographic, anatomic, histologic, histochemical and ultrastructural evaluations for submandibular glands.

RESULTSSialograms showed a long, horizontal main excretory duct and a pear-shaped gland located inferoposterior to the angle of the mandible. The submandibular glands lied superficial to the suprahyoid, and infrahyoid muscle groups, and were covered by the inferior portion of the parotid gland. The submandibular glands were characterized by a mixed parenchyma of mucous and serous secretory acini. Alcian blue (AB) staining and periodic acid-Schiff (PAS) reactions demonstrated that minipig submandibular glands synthesized and secreted acid mucous substances by serous cells and polysaccharide, and neutral mucous substances, by mucous cells.

CONCLUSIONThe submandibular gland of the minipig is considered a useful large salivary gland animal model for biomedical studies.

Animals ; Female ; Histocytochemistry ; Submandibular Gland ; chemistry ; cytology ; physiology ; ultrastructure ; Swine ; Swine, Miniature ; anatomy & histology

OBJECTIVETo study the anatomy of the small intestine,and investigate the optimal selection of donors,recipients,and their small intestine vessels in piglet small intestine transplantation.

METHODSThe weight and length of 30 piglets were measured. Angiography and pigments perfusion were used to observe the main vessels of the small intestine,and the length of the small intestine,and the external diameter of the main vessels of the small intestine were measured in vivo and ex vivo.

RESULTSThe length of the small intestine was 11.5 times as long as the body length, and its weight accounted for 2.3% of the body weight. The outer diameters of abdominal aorta (AT), mesenteric anterior artery (MAA) and its 5(th)-6(th) branches in vivo and ex vitro were 4.3/4.6mm, 2.5/2.7mm and 1.9/2.2mm respectively. The total number of MAA's branches was 6-8 in general and its 5(th)-6(th) branches were the longest [(20.0 +/- 7.0) mm, (22.0 +/- 8.2) mm]. The outer diameter of mesenterial anterior vein (MAV) was 1-2 mm wider than that of MAA.

CONCLUSIONSAT, MAA and its 5(th)-6(th) branches are the preferable vessels for small intestine transplantation. In segmental small intestine transplantation, the length of the small intestine and body weight can be used to primarily select the suitable animals.

Animals ; Blood Vessels ; anatomy & histology ; Female ; Intestine, Small ; blood supply ; transplantation ; Male ; Organ Transplantation ; Swine ; Swine, Miniature

OBJECTIVE: To explore the histological structure of the deciduous teeth and the tooth germs of Tibetan miniature pigs for studies of dental tissue diseases and tooth regeneration. METHODS: The structure of the deciduous teeth of Tibetan miniature pigs was observed by X-ray. The ultrastructure of the enamel and dentin of deciduous teeth was characterized by scanning electron microscopy. The jaws and teeth were three-dimensionally reconstructed using Mimics software based on Micro-CT scanning of the deciduous teeth. Image J software was used to calculate the gray value and the mineralization density of the deciduous teeth. Hisotological structure of the tooth germ and the pulp tissue of Tibetan miniature pigs was observed using HE staining. RESULTS: The deciduous teeth of Tibetan miniature pigs were composed of enamel, dentin and medullary pulp tissue. The permanent tooth germ were formed during the deciduous dentition. The enamel and dentin ultrastructure of deciduous teeth were consistent with that of human deciduous teeth. The enamel and dentin mineralization densities were 2.47±0.09 g/cm and 1.72±0.07 g/cm, respectively. The pathological structures of tooth germ and pulp tissue were similar to those of human teeth, and the pulp tissue of the deciduous teeth was in an undifferentiated state. CONCLUSIONS The deciduous teeth of Tibetan miniature pig have similar anatomy, ultrastructure and histopathological structure to human teeth and can serve as a good animal model for studying human dental tissue diseases and the mechanisms of tooth regeneration.
Animals ; Dental Enamel ; ultrastructure ; Dental Pulp ; Dentin ; ultrastructure ; Swine ; Swine, Miniature ; Tibet ; Tooth Germ ; Tooth, Deciduous ; anatomy & histology

OBJECTIVETo study the ultrastructure of parotid glands, lacrimal glands and pituitary glands between miniature pig and mouse.

METHODSFive adult miniature pigs and 5 mice were studied. Ultrastructure of their parotid glands, lacrimal glands, and pituitary glands was observed.

RESULTSThe secretary granules in acinar cell of miniature pig parotid glands showed higher density and more aequalis than those of mice. The cell apparatus in acinar cell of mouse parotid glands were more plentiful than those of miniature pigs. The secretary granules on blood vessel wall were richer in parotid gland of miniature pigs compared with mouse parotid gland. Lacrimal gland had the similar ultrastructure to parotid gland in these two animals. Many blood vessel antrum were found in pituitary glands of these two animals.

CONCLUSIONSCompared with mouse parotid glands, there are more secretary granules in acinar cells and vascular endothelial cells in miniature pig parotid glands, which might enter blood stream and have function of endocrine secretion.

Animals ; Lacrimal Apparatus ; ultrastructure ; Male ; Mice ; Mice, Inbred Strains ; anatomy & histology ; Parotid Gland ; ultrastructure ; Pituitary Gland ; ultrastructure ; Swine ; Swine, Miniature ; anatomy & histology

Multidetector row computed tomography (MDCT) provides anatomical information about the kidney and other internal organs. Presently, the suitability of 64-channel MDCT to assess the kidney of healthy micropigs was evaluated. Morphological evaluations of the kidney and the major renal vessels of six healthy micropigs were carried out using MDCT, recording kidney volume and the diameter and length of renal arteries and veins. The mean diameters and lengths of the renal artery were 0.44 +/- 0.05 and 4.51 +/- 0.55 cm on the right side and 0.46 +/- 0.06 and 3.36 +/- 0.27 cm on the left side, respectively. The mean diameters and lengths of the renal vein were 1.44 +/- 0.52 and 4.22 +/- 1.29 cm on the right side and 1.38 +/- 0.17 and 5.15 +/- 0.87 cm on the left side, respectively. The mean volume of the right kidney was 79.3 +/- 14.5 mL and of the left kidney was 78.0 +/- 13.9 mL. The data presented in this study suggest that the MDCT offers a noninvasive, rapid, and accurate method for the evaluation of the renal anatomy in living kidney donors. It also provides sufficient information about extra-renal anatomy important for donor surgery and determination of organ suitability.
Animals ; Kidney/*anatomy & histology/blood supply ; Kidney Transplantation/methods/*veterinary ; Male ; Renal Artery/*anatomy & histology ; Renal Veins/*anatomy & histology ; Swine ; Swine, Miniature/*anatomy & histology ; Tissue and Organ Procurement/methods ; Tomography, X-Ray Computed/methods/*veterinary

Due primarily to the increasing shortage of allogeneic donor organs, xenotransplantation has become the focus of a growing field of research. Currently, micropigs are the most suitable donor animal for humans. However, no standard method has been developed to evaluate the systemic vascular anatomy of micropigs and standard reference values to aid in the selection of normal healthy animals as potential organ donors are lacking. Using 64-channel multidetector row computed tomographic angiography (MDCTA), we evaluated morphological features of the major systemic vessels in micropigs and compared our results to published human data. The main vasculature of the animals was similar to that of humans, except for the iliac arterial system. However, diameters of the major systemic vessels were significantly different between micropigs and humans. Specifically, the diameter of the aortic arch, abdominal aorta, external iliac artery, and femoral artery, were measured as 1.50 +/- 0.07 cm, 0.85 +/- 0.06 cm, 0.52 +/- 0.05 cm, and 0.48 +/- 0.05 cm, respectively, in the micropigs. This MDCTA data for micropig major systemic vessels can be used as standard reference values for xenotransplantation studies. The use of 64-channel MDCTA enables accurate evaluation of the major systemic vasculature in micropigs.
Animals ; Aorta/*anatomy & histology ; Aortography/veterinary ; Femoral Artery/*anatomy & histology/radiography ; Humans ; Iliac Artery/*anatomy & histology/radiography ; Male ; Reference Values ; Swine ; Swine, Miniature/*anatomy & histology ; Tomography, X-Ray Computed/methods/*veterinary ; *Transplantation, Heterologous

Micropigs are the most likely source animals for xenotransplantation. However, an appropriate method for evaluating the lung of micropigs had not been established. Therefore, this study was performed to evaluate the feasibility of 64-channel multi-detector row computed tomography (MDCT) to measure the diameter of the pulmonary arteries and the lung volume in micropigs. The mean diameters of the trachea, and left and right bronchi were 1.6 +/- 0.17, 1.18 +/- 0.14, and 1.1 +/- 0.11 cm, respectively. The mean diameters of the main, right, and left pulmonary arteries were 1.38 +/- 0.09, 1.07 +/- 0.26, and 0.98 +/- 0.13 cm and the diameters of right, left, and common inferior pulmonary veins were 0.97 +/- 0.20, 0.76 +/- 0.20, and 1.99 +/- 0.26 cm, respectively. The mean lung volume was 820.3 +/- 77.11 mL. The data presented in this study suggest that the MDCT may be a noninvasive, rapid, and accurate investigational method for pulmonary anatomy in living lung donors.
Animals ; Humans ; Lung/physiology/*radiography ; Organ Size/physiology ; Pulmonary Artery/physiology/*radiography ; Swine ; Swine, Miniature/*anatomy & histology ; Tomography, X-Ray Computed/*methods ; Transplantation, Heterologous/*methods

Somatic cell nucleus transfer (SCNT) has been considered the most effective method for conserving endangered animals and expanding the quantity of adult animal models. Bama miniature pigs are genetically stable and share similar biological features to humans. These pigs have been used to establish animal models for human diseases, and for many other applications. However, there is a paucity of studies on the effect of ear fibroblasts derived from different age of adult Bama miniature pigs on nucleus transfer (NT). The present study examined the NT efficiency of ear fibroblasts from fetal, newborn, 1-, 2-, 4-, 6-, 12-month-old miniature pigs by using trypan blue staining, flow cytometry and NT technique, etc., and the cell biological function and SCNT efficiency were compared between groups. The results showed that ear fibroblasts grew well after passage in each group. Spindle-shaped cells initially predominated, and gradually declined with increase of culture time and replaced by polygonal cells. Irregular cell growth occurred in the 2-month-old group and the elder groups. The growth curves of the ear fibroblasts were "S-shaped" in different age groups. The cell proliferation of postnatal ear fibroblasts, especially those from 2-, 4-, 6-, 12-month-old miniature pigs was significantly different from that of fetus ear fibroblasts (P<0.05 or P<0.01). Two-month- and 4-month-old ear fibroblasts had a significantly higher proportion of G1 stage cells (85% to 91%) than those at 6 and 12 months (66% to 74%, P<0.01). The blastocyst rate of reconstructed embryos originating from newborn, 1-, 2-, 4-month-old donor pigs was 6.06% to 7.69% with no significant difference from that in fetus fibroblast group (8.06%). It was concluded that <4-month-old adult Bama miniature pigs represent a better donor cell resource than elder pigs.
Animals ; Blastocyst ; physiology ; Cell Proliferation ; Cells, Cultured ; Ear ; embryology ; growth & development ; Fibroblasts ; cytology ; physiology ; transplantation ; Nuclear Transfer Techniques ; Swine ; Swine, Miniature ; anatomy & histology ; embryology ; growth & development

OBJECTIVETo construct a three-dimensional (3D) liver model of Wuzhishan mini-pig for virtual liver surgeries.

METHODSThe biliary tree and hepatic arteries of Wuzhishan mini-pig were perfused with perchloroethylene and ethyl acetate along mixed with lead oxide, and the hepatic vein and portal vein were perfused with a mixture of dental base acrylic resin and lead oxide. The sectional images were acquired using a 64-slice spiral CT, and the 3D models of the portal vein, hepatic vein, biliary tree, hepatic arteries, and liver parenchyma were reconstructed using Mimics software; the resection image of the liver was also designed. The intrahepatic vascular cast was prepared by corroding the soft tissue with hydrochloric acid.

RESULTS AND CONCLUSIONThe intrahepatic vascular cast obtained fully retained the vascular architecture and displayed the fifth- and sixth-level branches of the hepatic vein and portal vein and the third- and fourth-level branches of the artery and bile duct. The 3D model of liver allowed stereoscopic and accurate display of the third- and fourth-level branches of the hepatic vein and portal vein and the second- and third-level branches of the artery and bile duct. The 3D model showed fewer branches but represented the structural distribution identical to the cast. The 3D model could clearly display the spatial relationship between the vasculature and the soft tissue in virtual resection of the liver tissues, and thus provides a useful model for training of laparoscopic liver resection.

Animals ; Bile Ducts ; Hepatic Artery ; Hepatic Veins ; Imaging, Three-Dimensional ; Liver ; anatomy & histology ; Models, Anatomic ; Portal Vein ; Swine ; Swine, Miniature ; Tomography, Spiral Computed

The purpose of this study is to define the appearance of normal epiphyseal and metaphyseal marrow and normal changes of marrow due to fatty conversion on Gadolinium (Gd)-enhanced MR Imaging. Unenhanced and enhanced T1-weighted MR imaging were performed in proximal and distal femoral ends of 8 healthy piglets at the ages of 2, 4, 6 and 8 weeks, respectively. The changes with age in signal intensity and enhancement ratio of the epiphyseal and metaphyseal marrow with age were examined. The correlation of MRI characteristics with histological findings was studied. Our study showed that marrow of the metaphysis and of periphery of the 2nd ossification center were well vascularized hematopoietic marrow and had great enhancements. The enhancement ratio of metaphysis was greater than that of epiphyseal marrow and both enhancement ratios degraded gradually with age. The central regions of the epiphyseal ossification center and of the diaphysis were of fatty marrow and had little enhancement. It is concluded that on Gd-enhanced MR imaging the hematopoietic marrow of metaphysis and of periphery of the 2nd ossification center had greater enhancement than that of fatty marrow of central region of the 2nd ossification center. All of their enhancements decreased gradually with age.
Epiphyses/*anatomy & histology ; Femur/anatomy & histology ; Femur/*growth & development ; Gadolinium/*diagnostic use ; Growth Plate/*anatomy & histology ; Growth Plate/blood supply ; Growth Plate/growth & development ; Image Enhancement ; Magnetic Resonance Imaging ; Swine ; Swine, Miniature