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.     

Gross anatomy of the heart of the alpaca (Vicugna pacos,Linnaeus 1758)

The available information about anatomical characteristics of the cardiovascular system of the alpaca (Vicugna pacos, Linnaeus 1758) is scarce. The general objective of this work was to describe its heart anatomy. We dissected six adult animals and five neonates. The heart of the alpaca was located in the middle mediastinum, with a craniocaudal extension from the third to the sixth rib. No ligament that connected the fibrous pericardium to the sternum or to the diaphragm was detected. In the right atrium, there was a developed crista terminalis and small pectinate muscles. In the right ventricle, the septomarginal trabecula was very large. From the proximities of the interventricular septum arose small septomarginal trabeculae that ended in carnous trabeculae of the septal wall. The left atrium included little developed pectinate muscles. On the left ventricle, both papillary muscles were bilobed. Two left septomarginal trabeculas were detected in this ventricle. The left subclavian artery was originated from the aortic arch separately from the brachiocephalic trunk, and bicarotid trunk was present. The other branches of the subclavian artery were similar to the domestic ruminants. The arterial supply of the heart was of the right type. In conclusion, the heart anatomy of alpaca and the irrigation of thoracic cavity were more similar to those of old world camels and different from domestic ruminants.     

Anatomical Study of the Gastrointestinal Tract in Free‐living Axis Deer (Axis axis)

The macroscopic anatomy of the stomach and intestines of adult axis deer (Axis axis), a cervid species considered intermediate/mixed feeder, was observed and recorded. Nine adult wild axis deers of both sexes were used and studied by simple dissection. The ruminal papillae were distributed unevenly in the overall area of the inner surface of rumen and primarily were more large and abundant within the atrium. The ruminal pillars had no papillae. There was an additional ruminal pillar located between the right longitudinal and right coronary ventral pillars connected to the caudal pillar. No dorsal coronary pillars were found, and the ventral coronary pillars are connected. The reticulum was the third compartment in size, and the maximum height of the reticular crests was 1.0 mm. The Cellulae reticuli were not divided and rarely contained secondary crests. There were no Papillae unguiculiformes. The omasum was the smallest gastric compartment. The abomasum had about twelve spiral plicae, and a small pyloric torus was present. The intraruminal papillation was similar to those species that are characterized by a higher proportion of grass in their natural diet. The finding of the small reticular crests is typical for browser ruminants and was coincident with data reported for other deer. The comparative ratio of the small intestine to the large intestine was 1.69, in terms of length measurements in axis deer and appears below of the ‘browser range’. We concluded that the gastrointestinal system of axis deer reflected similar morphological characteristics of the both types of ruminants: browser and grazer, and we consider it as an intermediate feeder.     

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.     

Arterial Vascularization of the Gastrointestinal Tract of the Pampas Deer (Ozotoceros bezoarticus,Linnaeus, 1758)

Based on gross dissection of fifteen adult animals (11 females, 4 males), we described the arterial supply of the stomach and intestines of the pampas deer (Ozotoceros bezoarticus), a South American endangered species. The coeliac artery emitted the splenic, left gastric and hepatic arteries. The splenic artery directed towards the spleen, and the right ruminal artery, which is its only collateral directed towards the stomach, being the main artery of the rumen. The left gastric artery gave origin to the left ruminal, the reticular and the left gastroepiploic arteries. The left gastroepiploic artery originated the reticular accessory artery. Both arteries, gastric and left gastroepiploic, anastomosed their right counterparts derived from the hepatic artery on the curvatures of the abomasum. The cranial mesenteric artery irrigated the second half of the duodenum until the beginning of the descending colon. The thickest branch emitted by the cranial mesenteric artery was the ileocolic artery, which was destined to the ascending colon, caecum and ileum. The colic branches and the right colic arteries were irradiated on the right surface of the spiral loop of the ascending colon and distributed to both centripetal and centrifugal coils of the ascending colon; the colic branches were also anastomosed with the last jejunals and ileals and with the right colic arteries. There were no variations in the origin of any of the main branches derived from the coeliac and cranial mesenteric arteries. This species had a basic pattern of arterial distribution similar to small domestic ruminants.     

The Branching Pattern of the Brachiocephalic Trunk in the Donkey (Equus asinus)

Donkeys are a member of the horse family (Equidae) and share a common ancestor. However, in morphological terms, donkeys and horses are regarded as two separate subgenus. Given variations in the branching pattern of the brachiocephalic trunk (BCT) in different species of animals and the use of donkeys in anatomy courses at colleges of veterinary medicine, we conducted this study in order to investigate the branching patterns of BCT and to describe detailed morphological information regarding donkeys. Seventeen mature donkeys were examined following euthanasia by exsanguination from the common carotid artery under general anaesthesia. Thirteen donkeys were embalmed and injected with coloured latex from BCT origin for better visualization of vessels. Four other donkeys were freshly studied without the embalming procedure. In all cases, the BCT was the only branch of the aortic arch and branched into the left subclavian (LSb) artery, the right costocervical trunk, the right subclavian (RSb) artery and the bicarotid trunk. The main branching pattern of the RSb was the costocervical trunk, the vertebral artery, the internal thoracic artery and the superficial cervical artery. The deep cervical artery branched from the costocervical trunk. The major branching pattern of the LSb was the vertebral artery, the internal thoracic artery and the superficial cervical artery. In donkeys, the external thoracic artery branches from the internal thoracic artery. Results obtained from this study indicate that BCT branching in donkeys has some similarities and differences as compared to that in horses and in the Caspian miniature horse.     

Descriptive anatomic study of the great vessels of the heart in the capuchin monkey Cebus apella (Linnaeus, 1758)

The aim of this study was to describe the anatomy of the great vessels of the heart in capuchin monkey (Cebus apella) and to compare with those of other primates, including humans. The hearts were prepared through fixation in 10% formalin and subsequently dissected using standard techniques and instruments. The arterial and venous systems were perfused with colored latex solution via the femoral vessels. An ascending cylindrical branch with relatively great caliber was identified in the aorta artery, in addition to an aortic arch, from which three great arteries were originated, the brachiocephalic trunk, the left common carotid artery and the left subclavian artery. After a course of variable extension, the pulmonary trunk divided into right and left pulmonary arteries. The caudal vena cava was morphologically similar to that of humans, except for its association with the cardiac lobe of the right lung, whereas the cranial vena cava was formed by the two braquiocephalic veins and received the azygos vein close to right atrium. The pulmonary veins, in number of six, ended at the posterior face of the left atrium, differently from both humans and other primates. In conclusion, the morphology of the great vessels of the heart in Cebus apella was similar to that of humans and other primates, although some differences are evidenced with regards to topography and number of anatomic structures, particularly the relationship of the caudal vena cava with the cardiac lobe of the right lung and the presence of six pulmonary veins in Cebus apella.     

Arterial Vascularization and Morphological Characteristics of Adrenal Glands in the Pampas Deer (Ozotoceros bezoarticus,Linnaeus 1758)

This research presents morphological characteristics of adrenal glands and a demonstration of arterial vascularization in the Pampas deer, which is considered to be in extreme danger of extinction. A total of ten deer constituted the material of the study. Vascularization of organs was investigated by using latex injection technique. Left adrenal glands were basically supplied by coeliac, cranial mesenteric, renal and lumbal arteries. The arterial vascularization of the left adrenal glands was very complex in comparison with right adrenal glands. In two examples, branch of the lumbal artery was divided into phrenic caudal artery and cranial adrenal artery. In six examples, it was observed that the caudomedial and ventral regions of the left adrenal glands were also supplied by thinner branches that stemmed from second left lumbal artery. Besides, coeliac and cranial mesenteric arteries also gave off shorter branches supplying the cranial region of the left adrenal glands in five examples. It was determined that two branches originated from abdominal aorta directly for supplying left adrenal glands in only two examples. In four examples, two caudal adrenal arteries stemmed separately from left renal artery in a short distance. Arterial vascularization of right adrenal glands was more constant and supplied by lumbal and renal arteries. The adrenal glands were generally oval or round shaped. In only two examples, left adrenal glands were ‘V‐’ or heart‐shaped. There was no significant difference (P > 0.05) in sizes between right and left adrenal glands.     

Subgross investigation of vessels originating from arcus aortae in guinea-pig (Cavia porcellus)

The vessels that originate from the aortic arch were studied in 16 adult guinea-pigs. Two major vessels, the left subclavian artery and the brachiocephalic trunk, were easily identified as they were branching off from the aortic arch. The brachiocephalic trunk, at first branched off to the left common carotid artery and continued as a common trunk, which was then divided into the right subclavian artery and the right common carotid artery. The left subclavian artery branched off to the following vessels: the costacervical trunk, the internal thoracic artery, a common trunk from which the dorsal scapular artery and the vertebral artery originated, and the superficial cervical artery. The right subclavian artery branched off to the bronchoesophageal artery (in five cadavers), the caudal thyroid artery (in three cadavers) and the tracheal artery (in three cadavers) in addition to the above vessels. There were two vertebral arteries branching off to the right subclavian artery in all dissected cadavers. However, only 10 cadavers had two vertebral arteries originating from the left subclavian artery. The first vertebral artery originated from the common trunk, whereas the second vertebral artery arose from the dorsal scapular artery. The second vertebral artery entered the foramen transversarium of the seventh cervical vertebrae and anastomosed with the first vertebral artery just before entering the foramen transversarium of the sixth cervical vertebrae.     

Gross Anatomy of Pampas Deer (Ozotoceros bezoarticus,Linnaeus 1758) Mouth and Pharynx

The aims of this study were to describe the anatomy of the mouth and pharynx of the pampas deer, and to consider its evolutionary feeding niche according to those characteristics. Gross dissections of the mouth and pharynx were performed in 15 animals, 10 adult females and five young animals under 1 year (three males and two females), all dead by causes unrelated to this anatomical region. The upper lip entered in the constitution of a pigmented nasolabial plane. The masseter muscles weighed 43.8 ± 3.5 g and represented 0.23% of body weight, which corresponds to ruminants of feeders intermediate to grazers and browsers. Parotid glands represented 0.08% of the body weight, characteristic that also categorize the pampas deer as belonging to the intermediate feeding group. The dental formula was the same of the domestic ruminants. The upper incisors and canines were absent, and instead of them, there was a dental pad (Pulvinus dentalis). The upper canine teeth were present only in the deciduous dentition. The existence of a brachydont dentition turns Ozotoceros very vulnerable to continuous use as there is no compensatory teeth growth. The particular anatomy of the mouth and lips of this animal was adapted to a very selective feeding, taking highly nutritious sprouts beyond plant category. In conclusion and in addition to previous studies of anatomy of the digestive organs in this species, pampas deer may be categorized as belonging to the intermediate type of feeding.     

Three cases of aberrant right subclavian artery in the dog

In the normal dog only 2 arteries leave the ascending aorta–the brachiocephalic trunk and the left subclavian artery. This communication describes 3 dogs, a labrador, a poodle and a german shepherd, in which 3 large arteries left the ascending aorta–firstly a trunk for both common carotid arteries, then a left subclavian artery and finally a right subclavian artery.     

Angioarchitecture of collateral arteries of the aortic arch of Antillean manatee (Trichechus manatus manatus Linnaeus, 1758)

The aortic arrangement is an important structure associated with the maintenance of homeostasis. Based on this information, this study was conducted to describe the collateral arteries of the aortic arch of Antillean manatee and define the standard model for the species. Three specimens, an adult male, adult female and a male neonate, all strandings on the coast of the state of Rio Grande do Norte, Brazil, were used. The study was performed in the Laboratory of Morphophysiology of Vertebrates of the Federal University of Rio Grande do Norte, where in situ photographs were taken to demonstrate their topography. Subsequently, their hearts were removed and fixed in 10% formaldehyde and after 72 hr were dissected and analysed, obtaining schematic drawings and photographs of the vascular arrangement. The aortic arch was represented by three collateral arteries identified as the brachiocephalic trunk, left common carotid artery and left subclavian artery. This arrangement was similar to that found for other sirenians, and yet, for other mammals like hooded seal, murine, margarita island capuchin, black-handed tamarin, Mongolian gerbil and human. The morphological similarity presented in this study with different species of mammals, including humans, may contribute valuable information from an evolutionary point of view.     

Asymmetrical size and functionality of the pampas deer (Ozotoceros bezoarticus) testes: Right testis is bigger but left testis is more efficient in spermatogenesis

Information about gonadal asymmetries in ruminants is very scarce. In this work, we performed three complementary studies to compare characteristics of both testes: (i) weight and size of offspring and adult dead males; (ii) the tissue:fluid relationship determined by ultrasound scanning; and (iii) the spermatogenic status using fine needle aspiration cytology. The right testis was heavier than the left one in both offspring and adult animals and had greater width and volume in adult males than the left one. The ultrasound pixel intensity was similar in both testes. The right testis tended to have more spermatogonia (p = .06) and had a greater percentage of early spermatids (p = .004) than the left testis. On the other hand, the left testis had a greater percentage of spermatozoa (p = .05). The left testis had a greater spermatozoa/spermatogonia ratio (p = .02) and tended to have more spermatozoa/Sertoli cells ratio (p = .07). The spermatogenic index tended to be greater in the left than in the right testis (p = .06). Overall, we concluded that the right testis of pampas deer males is bigger but according to the cytology, it seems to be less spermatogenically effective than the left one, but these differences are not explained by different tissue:fluid ratio in each testis. Although differences were greater in adults than in offspring, asymmetry was observed even in just born offspring.     

Subgross and macroscopic investigation of blood vessels originating from aortic arch in the chinchilla (Chinchilla lanigera)

A total of 10 adult, healthy, male chinchilla (Chinchilla lanigera) were used to investigate the vessels originating from aortic arch. Coloured latex was injected into the carotid arteries following conventional anatomical applications in all the chinchillas examined. The brachiocephalic trunk and the left subclavian artery arose from the aortic arch at the level of the second intercostal region in the thoracic cavity. The right and left subclavian arteries detached branches at the level of first intercostal region and divided into the following vessels: internal thoracic artery, dorsal scapular artery, vertebral artery, superficial cervical artery and axillar artery. The vessels originating from the aortic arch displayed some significant differences in chinchillas compared to rats, guinea pigs, rabbits, porcupines and other laboratory rodents.     

ANGIOGRAPHIC APPEARANCE OF COMMON CAROTID COLLATERAL CIRCULATION IN THE GOAT RESULTING FROM PROSTHETIC GRAFT IMPLANTATION

Carotid arteriography was performed in six normal goats. The same procedure was performed on these six and 112 other goats at various time intervals after placement of an arterial graft in one or both carotid arteries. An arterial catheter was introduced into the femoral artery and advanced to the origin of the brachiocephalic trunk with the aid of image-intensified fluoroscopy. Hand-injection of the contrast medium resulted in complete opacification of both common carotid arteries in normal animals. Opacification of one or both of the vertebral arteries was usually seen in the goats with prosthetic grafts. The left vertebral artery was seen more often than the right, and when both vertebral arteries were seen together, the left was often larger. This angiographic method proved to be reliable for opacifying both common carotid arteries from their origin on the brachiocephalic trunk to the cranial cervical region. No clinical problems were associated with either the catheterization procedure or with the permanent ligation of the catheterized femoral artery.     

Xylazine-induced sedation in axis deer (Axis axis) and its reversal by atipamezole

Eight free-ranging axis deer (Axis axis) were captured in drive nets and injected with xylazine (3.4±0.1 mg/kg; mean ±SEM) intramuscularly using a hand-held syringe. Xylazine induced complete immobilization and sedation in three animals, heavy sedation in three, and moderate sedation in two. The mean induction time was 10.4±1.0 min. The mean rectal temperature, heart and respiratory rates of immobilized animals were 39.2±0.4°C, 75.5±6.5 beats/min and 62.1±4.2 breaths/min, respectively.All the animals were given atipamezole intravenously for reversal. The mean time from injection of xylazine to administration of atipamezole was 37.8±4.6 min. A dose ratio (w/w) for xylazine:atipamezole-HCl of 10:1 was used. The mean time from injection of atipamezole to mobility was 2.41±0.58 min.Atipamezole given intravenously effectively antagonized xylazine-induced sedation in axis deer. Only one animal showed signs of overalertness after reversal and no cases of resedation were observed.Abbreviations i.m. intramuscular(ly) - i.v. intravenous(ly) - SEM standard error of the mean     

Anatomic Study of The Collateral Branches of The Abdominal Aorta of Primate Species Saguinus niger

Saguinus niger is a primate of the family Callitrichidae, with a geographical distribution limited to northern Brazil, Guyanas, Suriname and Venezuela, where it inhabits rainforests along the coast. Three adult females from the Paragominas Bauxite Mine – PA were used, donated to the Laboratory of Animal Morphology Research (LAMR) of the Federal Rural University of Amazonia. These animals had died of natural causes. The arterial system was filled with latex, and the animals were fixed in 10% formalin. Afterwards, the abdominal aorta and its collateral branches were dissected. The arrangement of the abdominal aorta branches in this species showed a similar arrangement as domestic animals but differing in the formation of the coeliac trunk. The coeliac trunk originates from the abdominal aorta, and from this trunk, we found the hepatic, left gastric and splenic arteries, where the origin of these vessels was variable. These arteries originate from the coliac trunk or a common trunk originating from the coeliac trunk, a characteristic not described in other species. The other branches of the abdominal aorta from S. niger did not show great differences in origin when compared to other species.     

Comparative morphometrical studies on the skull bones of barking deer (Muntiacus muntjak) and sambar deer (Rusa unicolor)

The present study reports data on the skull bone morphometry of barking and sambar deer. The skulls of adult barking deer (n = 6) and sambar deer (n = 6) of either sex (n = 3 males and n = 3 females) were collected from the Aizawl Zoological Park, Aizawl, Mizoram, India, with official permission from the Government of Mizoram. Anatomically, barking and sambar deer's skulls were elongated, pyramid-like, dolichocephalic and consisted of thirty-two cranial and facial bones. The cranial bones were eleven (three single and four paired), comprising of occipital, sphenoid, ethmoid, frontal, interparietal, parietal and temporal. The facial bones were twenty-one (one single and ten were paired), consisting of the maxilla, premaxilla (incisive), palatine, pterygoid, nasal, lacrimal, zygomatic (malar), vomer, turbinates, mandible and hyoid. In the present study, altogether 41 different measurements were taken morphologically and 6 different indices were applied. The obtained morphometrical parameters were significantly (p < .01, p < .05) higher in males than females of both species. Species wise, all obtained parameters were higher in sambar deer than barking deer. The obtained 41 different skull parameters and 6 indices showed statistically significant differences (p < .01 and p < .05) between both sexes of barking and sambar deer; however, practically these differences were meagre. The present morphometrical study on the skull of both species can help the wildlife professionals and zoo veterinarians determine the sex of these animals and differentiate it from other domestic and wild small ruminants for solving veterolegal cases. This study's findings will also motivate and assist other comparative studies with various domestic and wild small ruminants.