Morphometry of mental foramina applied to local anesthesia in hoary fox (Lycalopex vetulus Lund, 1842) / Morfometría de forámenes mentales aplicada a la anestesia local en zorro de campo común (Lycalopex vetulus Lund, 1842)

In order to perform local anaesthetic blockade of the mental nerves, it is fundamentally to determine anatomical references, including the precise identification of the mental foramina; however, the literature does not present specific data on such structures in the Hoary Fox. Therefore, the objective was describing the morphometry of the mental foramina of this specie, in order to correlate its topographies with the mandibular anatomical reference points, supporting the effective technique for mental desensitization. For this purpose, four mandibles of adult bodies of Lycalopex vetulus were used. Bilaterally, three mental foramina were observed located on the rostral third of the lateral margin of the mandibular body. One of them is more caudal, positioned ventrally to the lower third premolar tooth; a medium one, is located ventrally to the lower first premolar tooth; and a rostral one, placed ventrally to the lower intermediate incisor tooth. There were no statistically significant differences between the antimeres. Therefore, it is indicated that the local anaesthetic block of the mental nerves in this species should be performed by inserting the needle approximately 4.4 mm in a ventrodorsal direction. It is necessary positioning it perpendicularly to the ventral margin of the mandibular body and juxtaposed to its lateral face, using as anatomical reference the interalveolar space located between the first two lower premolar teeth. Thus, that the point established for anaesthetic injection (caudal limit of the ventral margin of the middle mental foramen), provides greater safety for its realization since, for small animals, the recommendation for blockade is represented by needle penetration on the direction of emergence of the mental nerve and artery from this foramen, which makes these structures more exposed to iatrogenic lesions resulting from the technique.

Para realizar el bloqueo anestésico local de los nervios mentales, es fundamental determinar referencias anatómicas, incluida la identificación precisa de los forámenes mentales; sin embargo, la literatura no presenta datos específicos referente a estas estructuras en el zorro de campo común. Por lo tanto, el objetivo fue describir la morfometría de los forámenes mentales de esta especie, para correlacionar sus topografías con los puntos de referencia anatómicos mandibulares, apoyando la técnica efectiva para la desensibilización mental. Para este propósito, se utilizaron cuatro mandíbulas de Lycalopex vetulus adultos. Bilateralmente, se observaron tres resistencias mentales ubicadas en el tercio rostral del margen lateral del cuerpo mandibular. Uno de ellos es más caudal, posicionado ventralmente hacia el tercer diente premolar inferior; uno mediano, localizado ventralmente hacia el primer diente premolar inferior; y uno rostral, colocado ventralmente al diente incisivo intermedio inferior. No se observaron diferencias estadísticamente significativas entre los antímeros. Por lo tanto, el bloqueo anestésico local de los nervios mentales en esta especie debe realizarse insertando la aguja aproximadamente 4,4 mm en dirección ventrodorsal. Es necesario colocar ésta perpendicularmente al margen ventral del cuerpo mandibular y yuxtapuesto a su cara lateral, utilizando como referencia anatómica, el espacio interalveolar ubicado entre los dos primeros dientes premolares inferiores. De este modo, el punto establecido para la inyección de anestesia (límite caudal del margen ventral del foramen mental medio), proporciona una mayor seguridad para su realización ya que, para los animales pequeños, la recomendación de bloqueo está representada por la penetración de la aguja en la dirección de emergencia del nervio mental y la arteria de este foramen, lo que hace que estas estructuras estén más expuestas a las lesiones iatrogénicas resultantes de la técnica.

Morphometry of the mandibular foramen applied to local anesthesia in hoary fox (Lycalopex vetulus) / Morfometria do forame mandibular aplicada à anestesia local em raposa-do-campo (Lycalopex vetulus)

Great part of the veterinary care in wild carnivores is intended to treat the dental disorders, and oral cavity disorders may generally affect the animal health as a whole. It is factual that knowing the location of the mandibular foramen is vital for local anesthetic block of the inferior alveolar nerve, however, there is still no data on the morphometry of the hoary fox mandibular foramen. The aim was describing morphometry of the mandibular foramen of this species and associating its position with anatomic reference points in the mandible, thus providing support for more effective local anesthetic block of the inferior alveolar nerve in such species. Four adult jaws of Lycalopex vetulus were used. Radiography and biometrics of the hemimandibulas were performed. The rostral third of the jaw body in a lateral view presented three mental foramens, being a rostral, a medium and a caudal. Each hemimandibula presented I3/C1/PM4/M3. The angle of the mandible was marked by the masseteric fossa, the angular incisure, the angular process and the mandibular foramen, and this last one located perpendicularly to the dorsal edge of the angular incisures in medial view. In this view, the crevice to the milohyoid nerve, projected in the caudodorso rostral direction, was also evidenced. The ramus of the mandible was characterized by the presence of the condylar and coronoid processes, and by the dorsal and ventral mandibular incisions. Statistical analyzes did not present significant differences between the antimeres of the studied animals, and the penetration of the needle perpendicularly to the dorsal end of the angular incision on average 8.79mm, overlapped to the medial face of the angle of the mandible could be indicated. Alternatively, the access may also be achieved by inserting the needle in an average of 17.69mm perpendicular to the dorsal end of the angular process, in contact with the medial aspect of the angle of the mandible, and in caudo-rostral projection, also allowing a better anesthetic blockade of the inferior alveolar nerve in L. vetulus. It can also be concluded that the masseteric fossa, the dorsal and ventral mandibular angles, the crevice to the milohyoid nerve, the ramus of the mandible and the mandibular foramen presented differences in their topographic descriptions when compared to the other canids.(AU)

A maior parte dos atendimentos veterinários em carnívoros silvestres destina-se ao tratamento das afecções dentárias, sendo que doenças de cavidade oral podem afetar a saúde do animal como um todo. É factível que o conhecimento da localização do forame mandibular é essencial para o bloqueio anestésico local do nervo alveolar inferior, entretanto, ainda são inexistentes dados sobre a morfometria do forame mandibular de raposa-do-campo. Objetivou-se descrever a morfometria do forame mandibular desta espécie, e correlacionar sua posição com pontos de referência anatômica na mandíbula, oferecendo subsídio para um bloqueio anestésico local mais efetivo do nervo alveolar inferior nesta espécie. Foram utilizadas quatro mandíbulas de cadáveres adultos de Lycalopex vetulus. Realizou-se a radiografia e as biometrias das hemimandíbulas. O terço rostral do corpo da mandíbula em uma vista lateral apresentou três forames mentuais, sendo um rostral, um médio e um caudal. Cada hemimandíbula apresentou I3/C1/PM4/M3. O ângulo da mandíbula foi marcado pela fossa massetérica, pela incisura angular, pelo processo angular e pelo forame mandibular, e este último localizado perpendicularmente ao extremo dorsal da incisura angular em vista medial. Nesta vista, também se evidenciou o sulco para o nervo milohióideo, projetado em sentido caudodorsorostral. O ramo da mandíbula foi caracterizado pela presença dos processos condilar e coronóide, e pelas incisuras mandibulares dorsal e ventral. As análises estatísticas não apresentaram diferenças significantes entre os antímeros dos animais estudados, podendo-se indicar a penetração da agulha perpendicularmente ao extremo dorsal da incisura angular em média 8,79mm, justaposto à face medial do ângulo da mandíbula. Alternativamente, o acesso também poderá ser realizado introduzindo a agulha em média 17,69mm de forma perpendicular ao extremo dorsal do processo angular, em contato com a face medial do ângulo da mandíbula, e em projeção caudorostral, permitindo também um melhor bloqueio anestésico do nervo alveolar inferior na L. vetulus. Também se pode concluir que a fossa massetérica, as incisuras angular, mandibulares dorsal e ventral, o sulco para o nervo milohióideo, o ramo da mandíbula e o forame mandibular apresentaram diferenças em suas descrições topográficas quando comparados aos demais canídeos.(AU)

Anatomy of the abdominal aorta in the hoary fox (Lycalopex vetulus,Lund, 1842) / Anatomia da aorta abdominal em raposa-do-campo (Lycalopex vetulus, Lund, 1842)

The hoary fox (Lycalopex vetulus,Lund, 1842) is the smallest Brazilian canid, whose weight varies between 2 and 4 kg, has a slender body, a small head, and a short and blackened snout. Despite being considered an endemic species, little is known about the hoary fox as it is one of the seven less studied canids in the world. Thus, this study aimed to describe the anatomy of the abdominal aorta artery of the hoary fox and to compare it with the pre-established literature data in domestic canids. For this purpose, we used two adult hoary foxes without definite age. We collected the corpses of these animals along roadsides of Catalão-GO, being later fixed and conserved in a 10% formalin solution. The results showed that the abdominal aorta in hoary fox is at the ventral face of the lumbar region vertebral bodies, being slightly displaced to the left of the median plane. The first branch is visceral, named celiac artery, followed by a paired parietal branch: the phrenic abdominal arteries. The third and fourth branches are the cranial mesenteric arteries and the right and left are the renal arteries, respectively. The posterior branches of the renal arteries are equally visceral, paired, being called testicular arteries. Distal to the latter, both the caudal mesenteric artery and deep circumflex iliac arteries originate. Finally, two large external iliac arteries and its terminal branches composed of internal iliac arteries and the median sacral artery originate. In addition, five pairs of lumbar arteries originate alongside the abdominal segment of the aorta. Considering these findings, it is possible to conclude that despite the hoary fox being a wild animal, the anatomy of its abdominal aorta is very similar to that of domestic canids.(AU)

A raposa-do-campo (Lycalopex vetulus,Lund, 1842) é o menor canídeo brasileiro, cujo peso varia entre 2 e 4 quilos, possui corpo esguio, a cabeça é pequena, focinho curto e enegrecido. Considerada uma espécie endêmica, pouco se sabe a seu respeito, e é um dos sete canídeos menos estudados no mundo. Assim, o presente estudo teve o objetivo de descrever a anatomia da parte abdominal da artéria aorta em raposa-do-campo e comparar com dados literários pré-estabelecidos de canídeos domésticos. Para a realização deste estudo foram utilizados dois exemplares de raposa-do-campo, adultos, sem idade definida. Os cadáveres dos animais foram recolhidos às margens de rodovias no entorno da Catalão-Goiás, fixados em solução aquosa de formol a 10% e conservados na mesma solução. Os resultados mostraram que a aorta abdominal da raposa-do-campo está localizada sobre a face ventral dos corpos vertebrais da região lombar, levemente deslocada para a esquerda do plano mediano. O primeiro ramo é visceral, denominado artéria celíaca, seguido por um ramo parietal, pareado, as artérias frênico-abdominais. O terceiro e quarto ramos são a artéria mesentérica caudal e as artérias renais direita e esquerda, respectivamente. Os ramos posteriores das artérias renais são igualmente viscerais, pareados, denominados artérias testiculares. Distal à essas últimas, originam-se a artéria mesentérica caudal e as artérias circunflexas ilíacas profundas. Finalmente surgem duas grandes artérias ilíacas externas e os ramos terminais compostos pelas artérias ilíacas internas e artéria sacral mediana. Ao longo do trajeto da aorta abdominal, cinco pares de artérias lombares se originam da face dorsal. Considerando esses achados, pode ser concluído que a anatomia da aorta abdominal da raposa-do-campo é muito similar àquela de canídeos domésticos, embora ela seja um animal silvestre. (AU)

Anatomical variations of the caudomedial antebrachial muscles in the crab-eating fox (Cerdocyon thous) / Variaciones anatómicas de los músculos caudo-mediales del antebrazo del zorro perruno (Cerdocyon thous)

The crab-eating fox (Cerdocyon thous) is a wild canid distributed in South America, which is susceptible to traumas caused by captors, accidents on roads, and traps. Due to these events their thoracic limbs can be involved at the level of the forearm, therefore, knowledge of the gross anatomy of its muscles is important in order to develop clinical and surgical procedures at this level compared with the domestic dog. The main objective of this investigation was report the intra and interspecific anatomical variations of the caudomedial forearm muscles in Cerdocyon thous in comparison mainly with the domestic dog. Six dead specimens from wildlife care centres of CORPOCALDAS were used. These were fixed with a solution of formaldehyde, mineral oil and phenic acid. Both thoracic limbs of each specimen were dissected from superficial to deep, emphasizing the caudomedial part of the forearm in order to review the anatomical characteristics of each muscle. These muscles were similar to those reported in the domestic dog, but some variations were observed such as the innervation of the pronator teres muscle by the musculocutaneous nerve in a specimen unilaterally; the formation of an accessory muscle from the ulnar head of the flexor carpi ulnaris muscle in most specimens; and the vestigial presence of the anconeus epitrochlearis muscle in a specimen bilaterally.

El zorro perruno (Cerdocyon thous) es un cánido silvestre distribuido en Sudamérica, el cual es susceptible a traumas causados por captores, accidentes en carreteras y trampas, donde pueden verse involucrados sus miembros torácicos a nivel del antebrazo, por lo tanto, conocer la anatomía de sus músculos es importante, ya que ésta servirá como base en la realización de procedimientos clínicos y quirúrgicos a este nivel en comparación con el perro doméstico. El objetivo principal de esta investigación fue reportar las variaciones anatómicas intra e interespecíficas de los músculos caudo-mediales del antebrazo de C. thous en comparación principalmente con el perro doméstico. Se utilizaron seis especímenes muertos bajo la jurisdicción de CORPOCALDAS. Estos se fijaron con una solución en mezcla de formaldehído, aceite mineral y ácido fénico. Se diseccionaron de superficial a profundo los dos miembros torácicos de cada espécimen, haciendo énfasis en la parte caudo-medial del antebrazo para revisar las características anatómicas de cada músculo, las cuales fueron similares a las reportadas al perro doméstico, pero se observó en un espécimen de manera unilateral la inervación al músculo pronador teres por parte del nervio musculocutáneo; en la mayoría de especímenes se observó la formación de un músculo accesorio a partir de la cabeza ulnar del músculo flexor ulnar del carpo; y en un espécimen la presencia vestigial del músculo ancóneoepitroclear.

Cortical branches of the middle cerebral artery in silver fox (Vulpes vulpes)

The study of the vascularization of the cerebrum in silver fox was performed on 80 cerebral hemispheres. It was found that the middle cerebral artery is the strongest vessel supplying blood to the cerebrum. The artery gets divided into ten permanent branches. Two olfactory arteries supply the region of the cerebrum located on the border between the old and the new cortex. The other eight supply the region of the new cortex. The frontal, parietal and temporal branches descended independently from the main trunk of the middle cerebral artery or formed a common trunk. Common trunks for respective groups of branches have been described as the anterior, superior and posterior middle cerebral artery. The alterior olfactory artery in 5% of cases and posterior olfactory artery in 2.5% of cases were independent branches of the middle cerebral artery extending from the rostral cerebral artery.(AU)

Descripción anatómica del músculo extensor del I y II dedo de la mano del zorro perruno (Cerdocyon thous Linnaeus, 1766) / Anatomical description of crab-eating fox' (Cerdocyon thous Linnaeus, 1766) extensor of digit i and ii muscle

El zorro perruno (Cerdocyon thous) es el cánido silvestre más común en América del Sur, con una relativa estabilidad poblacional, pero susceptible de ser atropellado y caer en trampas, pudiendo sufrir traumas en sus miembros torácicos, por lo tanto se requiere un conocimiento anatómico específico de sus músculos para intervenciones médicas y quirúrgicas. El objetivo principal de esta investigación fue realizar una descripción anatómica del músculo extensor del I y II dedo del C thous, en la cual, se reporta forma, origen, inserción, inervación e irrigación. Se diseccionaron de superficial a profundo los dos antebrazos de seis especímenes muertos donados por CORPOCALDAS a la Universidad de Caldas. El músculo extensor del I y II dedo en este estudio presentó características anatómicas similares a las reportadas a otras especies pero con una distribución tendinosa variante formando desde tres a cuatro ramas que se distribuyen del I al III dedo, incluso faltando a veces para el III dedo, pero de igual forma presenta una distribución que debe ser conocida para procedimientos que requieran de su conocimiento.

The crab-eating fox (Cerdocyon thous) is the most common wild canid in South America. With a relative demographic stability, this animal is susceptible of being hit and falling into traps, and can suffer trauma in its thoracic limbs; therefore a specific anatomical knowledge about its muscles is necessary for medical and surgical procedures. The main aim of this research was to describe the anatomy of the extensor muscle of digit I and II of the C. thous reporting form, origin, insertion, innervation and irrigation. The forearms of six donated dead specimens from CORPOCALDAS to Caldas University were dissected from superficial to deep. In this research, the extensor muscle of digit I and II showed similar anatomical features to those reported for other species but with a variant tendinous distribution that forms from three to four branches distributed from digit I to III. Although sometimes this distribution does not exist for the digit III; this similar distribution must be reported for procedures which require this knowledge.

Histology and scanning electron microscopy of the lower respiratory tract in the adult red fox (Vulpes vulpes) / Histología y microscopía electrónica de barrido de las vías respiratorias inferiores en el zorro rojo adulto (Vulpes vulpes)

The study was conducted on a total of three adult healthy freshly killed red foxes of both sexes weighing about 4-6 kg collected from Abou Rawwash, Giza, Egypt. The wall of trachea and bronchi formed of mucosa, submucosa and adventitia. The mucosa formed of pseudostratified columnar epithelium and lamina propria. The respiratory epithelium composed of tall columnar ciliated, goblet cells, basal cells, and neuroendocrine cells. Goblet cells account for about 20 to 30% of cells in the more proximal. Basal cells are relatively small triangular cells whose bases are attached to the basement membrane. The primary bronchiole is lined by simple columnar nonciliated to cuboidal epithelium containing some bronchiolar exocrine cells and some goblet cells. Neuroendocrine cells constitute about 4 to 5% of bronchial epithelial cells, attached at their bases to the basement membrane and have tapering apices. The lamina propria consists principally of a network of capillaries, a meshwork of connective tissue fibers continuous with the basement membrane. The submucosa formed of connective tissue elements and blood vessels and devoid of Tracheobronchial glands in red fox. The adventitia contain tracheal cartilage and muscle in trachea and bronchial cartilages and muscles in bronchi. Tracheal muscle is transverse bundles attached to the outer perichondrium. In the bronchi, muscle is organized in transverse bundles close to the epithelium adjacent to the lamina propria and longitudinal bundles close to the cartilages. Alveoli are demarcated by septa composed of a continuous layer of epithelial cells overlying a thin interstitium. The epithelial cells consist principally of type I and type II pneumocytes. SEM revealed that, the mucosal surface of both trachea and bronchi was completely covered by cilia. There were few glandular openings or goblet cell.

El estudio se realizó en tres zorros rojos adultos sanos, recién fallecidos, de ambos sexos, con un peso aproximado 4,6 kg recogidos de Abou Rawwash, Giza, Egipto. La pared de la tráquea y los bronquios estaban formados por mucosa, submucosa y adventicia. La mucosa estaba formada por un epitelio estratificado y lámina propia. El epitelio respiratorio ciliado compuesto de células caliciformes, células basales y células neuroendocrinas. Las células calciformes representaban alrededor del 20 al 30% de las células más proximales. Las células basales eran células triangulares relativamente pequeñas cuyas bases están unidas a la membrana basal. El bronquiolo principal está cubierto por un epitelio columnar simple no ciliado que contiene algunas células exocrinas bronquiolares y células caliciformes. Las células neuroendocrinas constituyen aproximadamente 4 a 5% de las células epiteliales bronquiales, unidas en sus bases a la membrana basal y tienen ápices de ahusamiento. La lámina propia consiste principalmente en una red de capilares, una malla de fibras de tejido conectivo continuo con la membrana basal. La submucosa formada por elementos del tejido conectivo y vasos sanguíneos y escasas glándulas traqueobronquiales. La capa adventicia contiene cartílago traqueal y muscular en la tráquea, y los bronquios cartílagos y músculos. En los bronquios, el músculo está compuesto de haces transversales cercanos al epitelio próximo a la lámina propia y haces longitudinales cerca de los cartílagos. Los alvéolos están delimitados por tabiques compuestos de una capa continua de células epiteliales que recubren un intersticio delgado. Las células epiteliales se componen principalmente de neumocitos tipo I y tipo II. El MEB reveló que la superficie de la mucosa de la tráquea y los bronquios estaba completamente cubierta por cilios. Se observaron pocas aberturas glandulares o células caliciformes.

Variación geográfica del zorro Lycalopex culpaeus (Mammalia, Canidae) en Chile: implicaciones taxonómicas

Geographic variation of the fox Lycalopex culpaeus (Mammalia, Canidae) in Chile: taxonomic implications. We studied the geographic variation of skulls of Lycalopex culpaeus using qualitative and quantative analyses. The sampling area covered Chile, from its northern portion, to Tierra del Fuego and the neighbouring Hoste island, as well as part of Argentina. Five subespecies are currently recognized from this large area. We found two morphotypes that are segregated geographically. Both groups mostly differ by morphometric attributes, followed by qualitative features. Specimens from northern Chile (Tarapacá and Antofagasta) have small skulls, short rostrum, a liriform sagital zone, and lack the interparietal crest. The second group is formed by specimens from north-western and central Argentina, central-south Chile, Patagonia, and the austral islands of Tierra del Fuego and Hoste. This group presents a strong sagital crest, large rostrum, and a large skull. Our results agree with observed patterns of mitochondrial DNA variation. We propose to retain the name L. c. andinus for the populations of northern Chile and to synonymize L. c. magellanicus, L. c. lycoides, and L. c. smithersi under L. c. culpaeus. Rev. Biol. Trop. 57 (1-2): 421-432. Epub 2009 June 30.

Mediante análisis cualitativos y cuantitativos, se estudió la variación geográfica del cráneo de Lycalopex culpaeus en Chile (desde Tarapacá a la islas australes), y de algunas poblaciones argentinas. En dicha distribución se reconocen cinco de las seis subespecies del culpeo. Los resultados muestran dos grupos morfológicos geográficamente segregados; los mismos se diferencian principalmente por atributos morfométricos, y secundariamente por caracteres cualitativos. individuos del norte chileno (Tarapacá y Antofagasta) presentan cráneos pequeños, poco desarrollados, hocico levemente corto, ausencia de cresta interparietal y una tenue zona sagital "liriforme". Por otra parte, los individuos del noroeste y centro argentino, centro sur chileno, Patagonia e islas australes (islas de Tierra del Fuego y Hoste) (grupo B), no muestran diferencias significativas en su morfometría dento-craneal. En el grupo B destacó una fuerte cresta interparietal y zona sagital, hocicos prolongados y cráneos de mayor tamaño que los del norte chileno. Nuestros resultados coinciden con estudios de patrones de variación en el ADN mitocondrial de cánidos de Chile. Por lo tanto, se propone mantener el nombre L. c. andinus para las poblaciones del norte de Chile y sinonimizar los taxones L. c. magellanicus, L. c. lycoides y L. c. smithersi bajo la forma L. c. culpaeus.