Arrangement of the Branches of the Aorta Abdominalis in the Wood Mouse (Apodemus sylvaticus)

Data on the distribution and variation of the abdominal arteries in the wood mouse, Apodemus sylvaticus, are given. Seventy specimens (44 males and 26 females) caught in the field were analyzed by injection of green latex solution and dissection. The general branching pattern of the aorta abdominalis is similar to those described in other rodents. There are certain differences, however, especially in the branching of the coeliac trunk, the origin of the genital arteries and the arrangement of the caudal mesenteric artery. Significant variability was detected in the distribution of the iliolumbar arteries about the testicular and ovaric arteries. Based on the observations and measurements carried out, some branching patterns of the aorta abdominalis are presented.     

Arterial supply to the rat colon

Rats are often used as animal models in studies such as on intestinal transplantation and anastomosis healing, which require colectomy. Although detailed information regarding arterial supply is important to establish accurate and reproducible experimental procedures, this has not been studied in the rat colon. Therefore, we analysed the detailed arterial distribution pattern and its individual variations in the colon of 34 rats. The rat colon received colic branches of the ileocolic artery, and the right, middle and left colic arteries. The single left colic artery constantly arose from the caudal mesenteric artery and was distributed to the descending colon, whereas the others showed variations in number and distribution. The ileocolic artery gave rise to one (12%) or two (88%) colic branches supplying the proximal ascending colon, and these branches formed rich, mesh-like anastomoses along the initial portion of the ascending colon. One (74%) or two (26%) right colic arteries originated from the cranial mesenteric artery and supplied the ascending colon and right colic flexure. Moreover, one (38%), two (56%) or three (6%) middle colic arteries emerged from the cranial mesenteric artery and were distributed to the transverse colon, left colic flexure and proximal descending colon. In total, we categorized the individual variations in arterial branching and anastomosis into 11 patterns. Arterial supply to the rat colon showed a specific pattern and frequent individual variations. These findings thus provide essential information for establishing reproducible models of rat colic surgery.     

Cranial Arterial Patterning in Greyhounds: Another Case of Internal Intraspecific Variation

The greyhound is a dog breed highly specialized to run fast (17 m/s) over short distances (Usherwood and Wilson, 2005). As a result, there are many anatomical structures correlated with this sprinting function. The branching patterns of vasculature supplying blood to the head, forelimbs and thorax (subclavian arteries and its branches) were described in 34 adult greyhound cadavers (22 male, 12 female) (donated with owner consent and used under a memorandum of understanding with the University of Adelaide Animal Ethics Committee) from silicone casts of the arch of the aorta and the cranial arteries. Chi‐squared analysis was used to test for pattern frequency differences, and t‐tests were used to analyse the differences between sex and symmetry. All measurements were scaled to a fixed measure, the Open Thorax Length (OTL), to correct for size variation between individuals. Significant differences were found between the left and right subclavian arteries in the greyhound. The length to the first branch as a percentage of the OTL was greater in the right subclavian artery than the left subclavian artery (P < 0.001). The interval between the first and last branches (branching interval) as a percentage of the OTL was larger in the left subclavian artery than the right subclavian artery (P < 0.001). The reason for these differences remains unclear. Nonetheless, intraspecific variations of the branching patterns of the subclavian arteries have been described in the greyhound, thus suggesting that breed‐specific variations in the cardiovascular system are likely to occur throughout domestic dogs.     

Electrofishing method improves evaluation of amphibian larvae abundance: a case of “beaver rivers”

There are many locations in Russia where Eurasian beaver (Castor fiber) populations have been restored. As a keystone species, beavers provide wide‐ranging direct and indirect impacts on aquatic ecosystems. In particular, beaver‐created ponds are sites for spawning and nursery places for tadpoles of the brown frogs (genus Rana). Because of such impacts, study techniques for assessing aquatic organism abundance are being developed. We compared two methods for estimating tadpole abundance: traditional catches by dipnet and electrofishing. Our results show that the dipnet catch data for the shallower ponds with larger water surface area were five times lower than that obtained by electrofishing. Therefore, we conclude that dipnet catches are not suitable for comparing the relative abundance of tadpoles in the two beaver ponds that were studied.     

Branching patterns of the adrenal arteries in the degu (Octodon degus)

The degu has drawn increasing attention for use as an experimental animal in stress response studies due to its physiological features, such as diurnality and seasonal breeding, which differ from conventional laboratory rodents. Stress response is elicited by steroid hormones secreted by the adrenal gland, whose functions are controlled by pituitary hormones reaching through the adrenal arteries. However, knowledge of the arterial anatomy of the degu adrenal gland remains insufficient. To address this issue, we observed adrenal arteries in 20 male degus injected with red-colored latex. Adrenal arterial branching patterns were classified into Types 1–4, which respectively have 1 to 4 parent arteries that give rise to the adrenal arteries. Based on the combination of the parent arteries, Types 2 and 3 were categorized into subtypes a to c, while Type 4 was categorized into subtypes a and b. On the left side, Type 2 (45%) and Type 3 (45%) were predominant, whereas Type 1 (5%) and Type 4 (5%) were infrequent. On the right side, Type 2 (50%) and Type 3 (45%) were predominant, whereas Type 4 (5%) was infrequent. Type 1 was not present. There were 0 to 4 cranial, 1 to 4 middle and 1 to 4 caudal adrenal arteries, with the total number varying from 2 to 9. The present observation provides knowledge of comparative anatomical features of the degu adrenal arteries, which can serve as an anatomical basis for comparative endocrinological studies.     

Anatomical and Morphometric Variations in the Arterial System of the Domestic Cat

We document the anatomical architecture and frequency of occurrence of variations in the branching pattern of the brachiocephalic artery and the origin of the internal iliac arteries in the domestic cat, a widely used model organism in both anatomical training and research. Based on the study of 56 preserved specimens, we observed three distinct arrangements in the branching pattern of the brachiocephalic artery. The most common pattern (52% of the examined specimens) was that in which the brachiocephalic artery was divided into two branches, the left common carotid artery and a common branch for the right subclavian artery and the right common carotid artery. The frequency of occurrence of each variation type was independent of the gender and body size. The internal iliac arteries originated caudal to the point at which the external iliac arteries branched off from the abdominal aorta. However, the portion of the abdominal aorta between the external and internal iliac arteries varied greatly in length and was not significantly correlated with its width, nor with body size or gender. This study is the first to report and quantify the occurrence of such variations in North American cats. Given the anatomical similarity between the cat and other felids, the results of this study can be applied to other species, including endangered species.     

麝鼠香腺Elovl1基因生物信息学分析及表达研究

【目的】 测定麝鼠超长链脂肪酸延伸酶1(elongase of verylong chain fatty acid 1,Elovl1)基因序列并进行生物信息学分析,探讨其在麝鼠香腺发育和泌香过程中的作用。【方法】 使用TRIzol法提取成年雄性麝鼠香腺总RNA,采用转录组测序技术获得麝鼠香腺Elovl1基因序列并测序;在GenBank数据库中下载啮齿目不同物种的Elovl1基因及其多转录本CDS序列并构建系统进化树;通过在线工具对Elovl1基因编码蛋白的理化性质及结构进行预测与分析;利用实时荧光定量PCR技术分析成年雄性麝鼠香腺发育周期内香腺组织中Elovl1基因的表达水平。【结果】 Elovl1基因在麝鼠香腺中表达2个转录本,能编码2个不同的蛋白,分别由313和279个氨基酸组成。Elovl1基因2个转录本在2~9月末的麝鼠香腺中均有表达,且表达量整体呈先上升后下降的趋势。Elovl1基因编码的2个蛋白均为稳定的亲脂性、非分泌蛋白,具有7个跨膜螺旋区,亚细胞定位均主要位于内质网。在啮齿目动物中,Elovl1基因进化与物种进化基本一致,仓鼠科与鼠科亲缘关系较近,麝鼠与水鼠平亲缘关系最近;同一物种Elovl1基因的不同转录本间相对保守,均按物种聚在一起且置信值普遍较高,旱獭例外。【结论】 Elovl1基因表达规律与麝鼠香腺的发育、萎缩及泌香周期相吻合,提示Elovl1与麝鼠香分泌相关,并参与了香腺细胞发育。     

Branching pattern of aortic arch in the Korean water deer

This study examined the branching pattern of the aortic arch and its major branches in Korean water deer (Hydropotes inermis argyropus, Heude, 1884). Silicone casts were taken from the vessels of 23 carcasses (male 14, female 9) with body weights ranging from 1.3-16.0 kg through a retrograde injection into the abdominal aorta. The findings were compared with those from other domestic ruminants. Only the brachiocephalic trunk (Bct) branched from the aortic arch in all carcasses. In 19 of the 23 cases, the Bct branched into the left subclavian artery (LSb), the left common carotid artery (LCc), and then trifurcated into the right common carotid artery (RCc), right costocervical trunk (RCct) and right subclavian artery (RSb). The subclavian artery (Sb) branched into the costocervical trunk (in left), internal thoracic artery (It), and superficial cervical artery (Sc) in that order, and continued as the axillary artery. Instead of separated carotid arteries, the bicarotid trunk from the Bct was observed in only three males and one female. Two of these males had different branching orders of the It and Sc from the Sb in one or both sides. The other male had a RCct from the RSb. The left costocervical trunk (LCct) arose from the LSb in all cases, and branched into the highest intercostal artery, the dorsal scapular artery, and the deep cervical arteries in that order, and continued as the vertebral artery. In 22 cases, the RCct branched directly from the Bct at the same point in which the RCc (or bicarotid trunk) and RSb separated. The artery branching pattern from the RCct was similar to that of the LCct. These results suggest that the Korean water deer has a Bct with different branching patterns from those of domestic ruminants.     

The effect of artificial occlusion of the Ramus navicularis and its branching arteries on the navicular bone in horses: an experimental study

The clinical, radiographic, arteriographic, scintigraphic and histological effects of experimental occlusion of the Ramus navicularis (R. Navicularis) and its branching arteries are evaluated. Occlusion of the R. navicularis and its branching arteries creates changes, arteriographically and histologically, which resemble those of navicular disease. The increased bone remodelling, the shift in arterial pattern, the formation of collaterals and the increased connective tissue in the synovial membrane and nutrient foramina, as a reaction to the reduction of the distal arterial supply of the navicular bone, are also pathological features in the navicular bones of horses with navicular disease. The results of the present study support the theory that a reduced distal arterial supply of the navicular bone is important in the pathogenesis of navicular disease.     

The Arterial Supply of the Male Reproductive System in the Hamster

The major arteries, the testicular, deferential, prostatic, internal pudendal and external pudendal arteries, supply the male genital organs of the hamster. The same arterial patterns are found in three strains, except that the external pudendal artery arises from the external iliac artery or internal iliac artery in the APG strain, but only from the external iliac artery in the CBN and ACN strains. The deferential and prostatic arteries form the arterial loop on the dorsal surface of the ventrolateral lobe of the prostate. This loop may play some importance parts in the functional interaction between the epididymis and the prostate. The caudal epididymal artery arises more frequently from the spermatic cordai portion of the testicular artery than from the cranial epididymal artery, and it never arises directly from the abdominal part of the testicular artery as reported in the rat, mouse and rabbit. The deferential artery may join with the cranial vesicular artery to form the common trunk (umbilical artery), but sometimes these arteries arise directly from the internal iliac artery.     

Anatomical Variations of the Blood Vascular System in Veterinary Medicine

Traditional veterinary anatomical models describe the branches of the caudal gluteal artery as the iliolumbar, cranial gluteal, lateral caudal, satellite of the ischiatic nerve and dorsal perineal arteries. However, some classical veterinary anatomy textbooks often indicate variations the general organization of the arterial tree, without giving any pattern of origin or illustrations of the different branching. The aim of this study was to investigate the presumptive variability of the caudal gluteal artery. Two hundred and thirty‐two pelvic halves from 116 adult dogs were examined. Twelve anatomical variations were found, nine occurring in more than 5% of the dogs, and three in <5%. A ‘long‐type’ internal iliac artery, which means short caudal gluteal and internal pudendal arteries, was identified, while a ‘perineal trunk’ was observed as an interesting arterial variation. If the caudal segment alone is taken into consideration, identical vascular patterns in both hemi‐pelvises are found in 17% of the dogs. Significant statistical correlation was found for four different types of anatomic variations and gender, two types of variations and body size, one type of variation for body side and one type of variation for head shape.     

Beaver Habitat Selection for 24 Yr Since Reintroduction North of Yellowstone National Park

Beavers (Castor canadensis) disappeared from drainages north of Yellowstone National Park in the mid-1900s because of trapping, a potential tularemia outbreak, and willow (Salix spp.) stand degradation by ungulates. Beavers were reintroduced in 1986 after a 40–yr absence with inventories of active-beaver structures completed each fall after reintroduction for 24 consecutive yr. We used this inventory to evaluate the expansion of beaver populations in a riparian environment recovering from past overuse by ungulates. Specifically, we investigated the density of active-beaver colonies and dams, the change in willow cover, and habitats associated with beaver expansion since reintroduction. Successful establishment and expansion of beavers indicate that sufficient resources were available to the population despite the suboptimal condition of riparian vegetation. Carrying capacity on third-order streams was reached approximately 14 yr after reintroduction (2000) with an average annual density of 1.33 (95th percentile = 1.23 ? 1.44 active colonies/stream km) between 2000 and 2010. The average annual density of beaver dams during this time was 2.37 (2.04 ? 2.71 active dams/stream km). Despite the beaver population being at carrying capacity in meadows since 2000, willow cover increased by 16% between 1981 and 2011. We speculate that beaver activities, together with reduced ungulate browsing from predation and habitat loss, combined to increase willow cover. Willow cover and height were positively associated with colony longevity, but numerous other influencing variables included secondary channels, sinuosity, stream depth, and sandbar width. Our results provide evidence that beaver reintroduction can be successful in riparian areas where willow stand condition is less than optimal and that beavers might ultimately improve willow condition. We suggest that reducing ungulate use of overgrazed riparian environments will facilitate the reestablishment of beaver populations. We also provide managers with habitats that should be identified in an environment targeted for reintroduction.     

Bicarotid Trunk in the Domestic Cat

The origin of the pair of common carotid arteries in the cat is inadequately described, and there are conflicting accounts in English veterinary anatomy textbooks published in the USA. We found one‐quarter of 40 adult domestic cats dissected had a bicarotid trunk (5 female, 5 male). When present, the bicarotid trunk arose from the brachiocephalic trunk approximately midway between the expected origins of the more frequently independently arising left and right common carotid arteries, and on average, it was 5.6 mm in length. Our findings make the incidence, topographical and measurement information available so that students and veterinarians can be aware of this not insignificant variation in branching of the major arteries, forming a bicarotid trunk, in the cranial mediastinum of domestic cats.     

Echinococcus multilocularis in Belgium: prevalence in red foxes (Vulpes vulpes) and in different species of potential intermediate hosts

Echinococcus multilocularis causes a rare but potentially lethal zoonotic infection in humans. This tapeworm is known to be endemic in foxes in several countries of Western and Central Europe. In Western Europe, the common vole (Microtus arvalis) and the water vole (Arvicola terrestris) are considered to be the most important intermediate host species of this cestode whereas the red fox is by far the most important final host. The purpose of this study was to provide data on the prevalences in Wallonia (Southern part of Belgium) both in the red fox and in different potential intermediate hosts. A total of 990 red foxes were examined between January 2003 and December 2004 for the presence of E. multilocularis. The average prevalence was 24.55% (22.38-27.87). Out of 1249 rodents or insectivores belonging to the species Apodemus sylvaticus, Arvicola terrestris, Clethrionomys glareolus, Microtus arvalis, Microtus agrestris and Sorex araneus, only one M. arvalis (out of 914-0.11% (0.003-0.61) and one C. glareolus (out of 23-4.3% (0.1-21.9) were found to be infected. However, the muskrat (Ondatra zibethicus) seems to be a good intermediate host as 11.18% (9.72-12.76) of the animals (n=1718) were found to be infected. A positive correlation was found between the prevalences in foxes and in muskrats in each of the different geological regions. This study indicates that the muskrat is highly sensitive to this zoonotic tapeworm and could perhaps represent a good bioindicator when studying the epidemiology of this parasitic infection in Belgium and in other countries where the muskrat is present.     

Complications of Balloon Catheterization Associated With Aberrant Cerebral Arterial Anatomy in a Horse With Guttural Pouch Mycosis

A 3-year-old Quarter Horse gelding was treated for left guttural pouch mycosis by ligation and balloon catheterization of the left internal carotid artery. Catheter advancement was shorter (10 cm) than the normally reported distance (13–15 cm), but was observed endoscopically during placement as it coursed within the internal carotid artery through the guttural pouch. The horse developed a persistently abnormal respiratory pattern after catheter placement, failed to gain consciousness, developed pulmonary edema, and died 5.5 hours postoperatively. Postmortem examination revelaed an aberrant left internal carotid arterial course with location of the embolectomy catheter at the junction of the basilar and caudal cerebellar arteries. Brainstem neuronal necrosis and alveolar and interstitial pulmonary edema were identified on histological examination. Angiography may be used to identify aberrant branching patterns. Failure to identify and occlude aberrant branches may result in fatal epistaxis and Brainstem lesions.     

Lateral Branches of the Testicular Artery Affect Testicular Shape in Adult Stallions

The objective of this study was to investigate the arterial patterns of the stallion testis in relation to testicular shape. Two hundred and fifty-one stallion testes were evaluated for the presence of the lateral branches of the testicular artery. Seven specimens had their testicular arteries filled with latex milk, fixed in 70% alcohol, and dissected. Two hundred six specimens (82%) had a single testicular artery and no lateral branches; 39 testes (16%) had one lateral branch of the testicular artery; and six testes (2%) had two lateral branches of the testicular artery each. The lateral branches of the testicular artery obtained from the adult stallions, more than 5 years old, were associated with distinct lateral bulging, giving them a pear-like shape, whereas similar vascular pattern in young colts, less than 1 year old, did not cause similar shape change. Five distinct patterns of the branching of the testicular artery were determined. We concluded that the lateral branches of the testicular artery are present in approximately 20% of stallion testes. This anatomic pattern is associated with a lateral bulge that develops slowly over several years and is associated with a change in testicular shape from an ellipsoid in colts to a pear-like shape in adult stallions.     

Normal ocular features, conjunctival microflora and intraocular pressure in the Canadian beaver (Castor canadensis)

Objective The aim of the study was to assess the ocular features, normal conjunctival bacterial and fungal flora, and intraocular pressure (IOP) in the Canadian beaver (Castor canadensis). Sample population Sixteen, apparently healthy beavers with no evidence of ocular disease, and live‐trapped in regions throughout Prince Edward Island. Procedures The beavers were sedated with intramuscular ketamine (12–15 mg/kg). Two culture specimens were obtained from the ventral conjunctival sac of both eyes of 10/16 beavers for aerobic and anaerobic bacterial and fungal identifications. The anterior ocular structures of all beavers were evaluated using a transilluminator and slit lamp biomicroscope. Palpebral fissure length (11/16 beavers), and horizontal and vertical corneal diameters (10/16 beavers) were measured. IOPs were measured in both eyes of 11/16 beavers using applanation tonometry. Both eyes of 3/16 beavers and one eye of 1/16 beavers were dilated using topical tropicamide prior to sedation to effect timely maximal dilation. Culture specimens and IOPs were not evaluated in these four animals. Indirect ophthalmoscopy was performed on 7/8 eyes of these four beavers. Results Conjunctival specimens from all eyes cultured positively for one or more isolates of aerobic bacteria. The most common isolate was Micrococcus spp. (five beavers; 9/20 eyes). Other isolates included a Gram‐positive coccobacilli‐like organism (four beavers; 7/20 eyes), Aeromonas hydrophila (three beavers; 4/20 eyes), Staphylococcus spp. (three beavers; 4/20 eyes), Gram positive bacilli (one beaver; 2/20 eyes), Enterobacter spp. (two beavers; 2/20 eyes), Streptococcus spp. (two beavers; 2/20 eyes), aerobic diphtheroids (one beaver; 1/20 eyes), and Pseudomonas spp. (one beaver; 1/20 eyes). Clostridium sordellii (one beaver; 1/20 eyes) and Peptostreptococcus spp. (one beaver; 1/20 eyes) were the sole anaerobic bacteria isolated. All conjunctival specimens were negative for growth of fungi. Ophthalmic examinations revealed the normal beaver eye and ocular adnexa included dorsal and ventral puncta, a vestigial third eyelid, and a circular pupil. Average palpebral fissure length was 9.36 mm (SD = 1.00) for both eyes. Mean horizontal and vertical corneal diameters of both eyes were 9.05 mm (SD = 0.64) and 8.45 mm (SD = 0.69), respectively. Mean IOP for the right and left eyes were 17.11 mmHg (SD = 6.39) and 18.79 mmHg (SD = 5.63), respectively. Indirect ophthalmoscopic examinations revealed normal anangiotic retinas. Conclusions Gram‐positive aerobes were most commonly cultured from the conjunctival sac of normal beavers, with Micrococcus spp. predominating. The overall mean IOP in ketamine‐sedated beavers was 17.95 mmHg. The beaver, an amphibious rodent, has an anangiotic retina.     

MULTIDETECTOR‐ROW COMPUTED TOMOGRAPHY PATTERNS OF BRONCHOESPHAGEAL ARTERY HYPERTROPHY AND SYSTEMIC‐TO‐PULMONARY FISTULA IN DOGS

Anomalies involving arterial branches in the lungs are one of the causes of hemoptysis in humans and dogs. Congenital and acquired patterns of bronchoesophageal artery hypertrophy have been reported in humans based on CT characteristics. The purpose of this retrospective study was to describe clinical, echocardiographic, and multidetector computed tomography features of bronchoesophageal artery hypertrophy and systemic‐to‐pulmonary arterial communications in a sample of 14 dogs. Two main vascular patterns were identified in dogs that resembled congenital and acquired conditions reported in humans. Pattern 1 appeared as an aberrant origin of the right bronchoesophageal artery, normal origin of the left one, and enlargement of both the bronchial and esophageal branches that formed a dense network terminating in a pulmonary artery through an orifice. Pattern 2 appeared as a normal origin of both right and left bronchoesophageal arteries, with an enlarged and tortuous course along the bronchi to the periphery of the lung, where they communicated with subsegmental pulmonary arteries. Dogs having Pattern 1 also had paraesophageal and esophageal varices, with the latter being confirmed by videoendoscopy examination. Authors conclude that dogs with Pattern 1 should be differentiated from dogs with other congenital vascular systemic‐to‐pulmonary connections. Dogs having Pattern 2 should be evaluated for underlying pleural or pulmonary diseases. Bronchoesophageal artery hypertrophy can be accompanied by esophageal venous engorgement and should be included in the differential diagnosis for esophageal and paraesophageal varices in dogs.     

Origenes de las arterias suprarrenales craneales y caudales de la rata albina (Rattusnorvegicus)

The origin of the cranial and caudal adrenal arteries were studied in the white laboratory rat. Colored latex neoprene was utilized in this investigation. The adrenal arteries were found to arise from the caudal phrenic or adrenophrenic trunks. Variations in origin are discussed.     

Arterial Blood Supply to the Stomach of the Muskrat (Ondatra zibethicus)

The vascularization of the stomach of the muskrat is provided by the celiac artery and its three branches, the splenic, the hepatic and the left gastric artery. Of these, the left gastric vessel constitutes the main blood supply to the organ. Its two terminal branches supply the body of the stomach, forming a rich vascular network for the glandular region of the organ. The other regions of the stomach, the fundus and the pyloric part are poorly vascularized.