The pelvimetry consists of the metric determination of the pelvis dimensions and its use is directly related to the reproduction. The cartilage closure time of the ossification centers varies according to the bone, some closing already in the uterine life and others remaining present for many years. The objective was to evaluate, radiographically, the pelvic diameters by pelvimetry during the first 24 months of life in pacas, the second lagest Brazilian rodent and an animal that has shown big recent scientific interest, aiming the estimated age determination. Twelve pacas were used, which were monthly radiographed up from birth until 24 months old, with the animals anesthetized. The pacas are dolicopelvic animals and with pelvis presenting strong tendency to constant growth along the 12 first months of age, fact that can be useful in the approximated animals’ age determination that do not have precise birth date, for example.
Background: The capybara (Hydrochoerus hydrochaeris) is the largest South American rodent species alive, and it preferentially inhabits floodable environments. Currently, capybara populations have been increasing owing to lack of predators and increased availability of food. This favors reemergence of Rocky Mountain spotted fever in the state of São Paulo, as these animals can play host to the Cayenne tick (Amblyomma cajennense), a vector of the bacteria that transmit this disease. The objective of this work was to perform anatomical and radiographic analyses on the teeth of capybaras to broaden knowledge on the morphology of this species, as scientific interest on capybaras has been growing owing to reemergence of Rocky Mountain spotted fever.Materials, Methods & Results: Six capybara carcasses from the state of São Paulo, Brazil, were taken to the Laboratory for Animal Anatomy of the School of Agricultural Sciences and Veterinary Medicine of UNESP - Jaboticabal for obtainment of heads by disarticulation of the cervical region. The heads were frozen at -18°C, and then sectioned medially with a band saw to avoid tissue overlap in radiographs. The head halves were radiographed in the Diagnostic Imaging Section at the Veterinary Hospital of UNESP-Jaboticabal in laterolateral projection. After taking the radiographs, the teeth were extracted from the dental arches using anatomical forceps and pliers, placed in 0.1% thymol, and kept at 4°C for up to 30 days. The teeth were dried using an air jet produced by a compressor, and placed in molds made of aluminum foil. The specimens were embedded in alternating layers of clear polymethylmethacrylate and liquid polymerization catalyst until each tooth was completely covered. After 24 h, the molds were removed, and the blocks were sectioned using a band saw. Transversal and longitudinal calcified tooth sections with a thickness of 1.5 mm were prepared. The sections were sanded using an automotive sander with 80-grit sandpaper, and then sanded by hand until a thickness of 0.12 mm was reached. The tooth fragments were removed from the resin, dehydrated in ethanol, clarified in xylene, and placed in a Petri dish containing glycerin for evaluation using a mesoscope and a negatoscope. Capybaras were found to have one incisor, one premolar, and three molar teeth in each dental hemiarch (superior and inferior). All teeth contained large, open roots. The root of the superior incisor is rostral to the root of the premolar tooth, and the root of the inferior incisor lies between the roots of the premolar and the first molar teeth. The inferior incisors are much larger than their superior counterparts, and their ends are chisel-shaped. The pulp cavity extends from the apical region to up to two-thirds of the longitudinal length of the tooth, and the enamel is arranged in layers. The roots of the four molar teeth are large and resemble several aggregated laminae arranged longitudinally - five laminae in the inferior molars, four laminae in the premolar, first and second molars, and 13 or 14 laminae in the third superior molar.Discussion: The dental formula of capybaras is similar to that of guinea pigs, chinchillas, and pacas, but different from that of agoutis. All teeth are aradicular as in guinea pigs and chinchillas because of the great tooth wear owing to feeding. In chinchillas and guinea pigs, the apex of the mandibular incisor tooth is located between the second and the third molar; in capybaras, it is located between the premolar and the first molar. The premolar and molar teeth of capybaras are similar to their counterparts in the paca and to the molars of elephants because they exhibit parallel internal laminae. The teeth of capybaras are similar to those of guinea pigs in terms of number and type of teeth, and similar to those of pacas and elephants regarding external morphology.
It is essential to humanely use live animals in research and teaching activities and consequently, to search for alternative methods that do not prejudice academic or scientific efforts. The objective of this work was to evaluate the opinions of veterinary undergraduate students as to the acceptability of using chemically prepared cat cadavers to teach surgical methods. Ten cadavers of cats were fixed with ethylic alcohol with 5% of glycerine (120ml/kg) for 60 days and preserved in 30% sodium chloride aqueous solution up to one semester. During the conservation time, students were asked to complete an evaluation form at the end of the surgery classes. The students assigned a score of 1 (very bad) to 10 (excellent) to the resistance of the skin (7.94±1.60). muscles (7.98±1.39). stomach (8.12±1.33). intestine (7.54±1.72). and urinary bladder (7.58±1.79) to incision/suture and the malleability of intestines (7.78±1.58), spleen (7.34±2.24) and liver (7.14±2.28) were evaluated. The average score was 7.68 ± 1.74, and 92% of the students were found to be in favor of the use of cadavers. In addition, 90% of the students favored initial surgical training with chemically preserved cadavers, followed by classes including live animals from the Veterinary Hospital who came for elective surgery, such as an orchiectomy or ovariohysterectomy.Support or Funding InformationFAPESP, process 2015/08259‐9.This abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.
Chronic stress exposure commonly increases adrenals weight and changes their morphology. This study aimed to compare four methods to delimitate the cortical and medullary layers of adrenals glands in Nelore bulls. Fresh adrenals did not present differentiation between layers. Then, frozen adrenals were distributed in plastics bags with fixative Bouin (G1), 96ºGL ethylic alcohol (G2), 10% formaldehyde (G3), or 2.5% glutaraldehyde (G4). After 12 hours of fixation, the G1 adrenal glands did not show the entire cortical layer marked by Bouin's solution. For G2 and G3 there was a poor contrast, while for G4 there was a reasonable contrast. After 24 hours of fixation, G1 had an excellent contrast between layers, while G2 and G4 had a reasonable contrast and G3 a very bad contrast. After 48 hours it was difficult to differentiate cortical and medullar layers for G1; for Group 2 we get a reasonable contrast; and for G3 the contrast was bad. For G4 the contrast was not as sharp due to the medulla became dark. It was concluded that fixation of adrenals must be done in Bouin's solution for 24 hours to obtain an effective evaluation of the adrenals' morphometry.
El objetivo del estudio fue evaluar la factibilidad de utilizar alcohol etílico (AE) y una solución acuosa de cloruro de sodio al 30% (SACS) en varios periodos de tiempo para la preparación de cadáveres de gatos para la enseñanza de técnicas quirúrgicas. Se utilizaron los cadáveres de 60 gatos. Los especímenes fueron fijados en AE, según grupo, por 30 días (G1), 30 y 60 días (G2) y 30, 60 y 90 días (G3), y a todos se les aplicó SACS a los 30, 60, 90 y 120 días de conservación y el resultado fue medido mediante el estudio biomecánico en los tejidos para determinar el mejor momento para interrumpir la fijación en AE, utilizando como control la mayor similitud en la resistencia tisular encontrada en cadáveres frescos. El uso de la técnica anatómica utilizando AE y SACS fue eficiente durante todo el experimento. No hubo diferencia significativa entre las medias de la fuerza máxima de ruptura (N) ni entre los grupos de almacenamiento en el SACS y el tiempo de control en ninguno de los grupos para las muestras de piel. Tampoco se observó diferencia significativa en la fuerza máxima entre los grupos de fijación y preservación, comparado al grupo control en los grupos para las muestras de yeyuno. No obstante, G2 presentó menor variación en la fuerza de ruptura (-0.21 mm), siendo, por lo tanto, el grupo más parecido a los animales frescos. Se encontró que la técnica anatómica utilizada es eficiente tanto para la fijación y para la conservación de cadáveres de gatos por hasta siete meses.
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