Quantification of the liver structure of zebrafish (Danio rerio) submitted to different diets and physical exercise.

The zebrafish has been used in research for over 80 years. In the last three decades, discoveries about the fundamental properties of development, regeneration, cancer, and other diseases have established the zebrafish as an important model organism in biomedical research. This study aimed to evaluate liver alterations in zebrafish by quantitatively assessing the areas occupied by hepatocytes, as well as connective and adipose tissues. Forty-eight adult Danio rerio (38 males and 10 females) of approximately 13 months of age were used. They were divided into four groups, with 12 animals each. The fish were randomly distributed to form the groups, which received a maintenance and/or hypercaloric diet, with or without the addition of physical exercise. The animals underwent six hours of forced exercise (5 cm/s) for thirteen weeks. The animals that practiced physical exercise had a higher volumetric density of the area occupied by hepatocytes (65.92%±1.81 - GMex and 50.75%±2.24 GHex) among the groups. The GH group had a higher volumetric density of the area occupied by connective tissue (15.12%±0.72), followed by the GHex group (13.53%±1.43). Regarding the volumetric density of the area occupied by adipose tissue, the GH group had a higher density (27.21%±1.36), followed by the GHex group (21.66%±1.11) with statistically significant differences. The GMex had a volumetric density of the area occupied by adipose tissue of 3.5%±0.76, while the GM had 5.7%±0.5, with statistical difference. In relation to the animals in the GHex group, they had 20.39% less fat than the animals in the GH group. The animals in the GMex group had 72.47% less fat than those in the GM group. It is concluded that the different dietary constitutions and the imposition of physical exercise were able to modify the structural architecture of the liver of Danio rerio. These are acceptable criteria for modulations, thus aiming at the control and possible interferences directly related to the metabolism of the species and therefore the control of diseases.

Macro- and microstructural descriptions of the zebrafish (Danio rerio) liver.

The liver is an essential metabolically active organ, responsible for many vital life functions such as metabolism, synthesis, and storage. This study describes the macroscopic and microscopic zebrafish liver and its temporal changes during a period of 13 weeks. Forty-six adult zebrafish were used (46), of which 27 were females and were 19 males. Seven fish were euthanized initially for macroscopic evaluation and 3 fish were euthanized weekly for 13 weeks for microscopic evaluation. Routine histological technique was performed; the slides were stained with haematoxylin/eosin and periodic acid-Schiff. The volumetric (Vv(h)) and numerical (Nv(h)) densities of hepatocytes and vacuolation intensity were determined weekly. The liver was located in the coelomic cavity ventrally to the swim bladder, slightly brownish and divided into 3 hepatic lobes. Microscopically, it consisted of hepatocytes forming a muralium duplex around the sinusoids. The staining of the cytoplasm of hepatocytes was more eosinophilic and more basophilic in males and females, respectively. There was no formation of portal triads and phagocytic cells. The gallbladder had transitional epithelium, and the bile ducts had simple cuboidal epithelium. The volume and numerical density of hepatocytes during the 13 weeks was not statistically different, but these parameters displayed a positive correlation. The vacuolation was due to the presence of glycogen. The zebrafish liver has macro and micro structural particular features while, quantitatively, the volume and number of hepatocytes showed great capacity to respond to the physiological needs of the animal at the time.

Morfologia e biometria do timo em araras dos gêneros Ara e Anodorhynchus / Morphology and biometry of the thymus gland in macaw of Ara and Anodorhynchus genera

Foram utilizados 12 exemplares de Ara ararauna - seis fêmeas e seis machos -, cinco exemplares de Ara chloropterus (uma fêmea e quatro machos) e dois exemplares de Anodorhynchus hyacinthinus - uma fêmea e um macho -, todos adultos, doados por criadouro particular, após óbito natural. Os lobos foram dissecados e medidos com paquímetro - comprimento x largura x espessura - e analisados quanto ao peso, à topografia e à morfologia individual. Independentemente do gênero, foram identificados, em 17 casos (89,5%), lobos tímicos nos antímeros cervicais esquerdo e direito, e em oito casos (42,1%), lobos na cavidade celomática. Os lobos apresentaram formatos alongados - 52,6% -, arredondados - 21,1% - ou ovalados - 15,8% -, posicionados preferencialmente ventromedialmente ao longo do plexo vasculoneural do pescoço, com número médio de cinco lobos por antímero, tamanho médio de 0,49cm de comprimento, 0,12cm de largura e 0,05cm de espessura e peso médio de 0,076g.

Twelve samples of Ara ararauna - six females and six males -, five samples of Ara chloropterus (one female and four males) and two samples of Anodorhynchus hyacinthinus (one female and one male), all adults from a Breeding Park, were used after natural death. The lobes were dissected and measured with electronic calliper (length x width x thickness) and analyzed taking their weight, topography and individual morphology into account. Regardless of gender, 89.5% of the cases presented timic lobes in the left and right cervical antimere, and 42.1% of the cases presented lobes in the celomatic cavity. The lobes were shown in shapes - long (52.6%), round (21.1%) or oval (15.8%), positioned mostly ventromedially, along the neurovascular plexus of the neck, with an average of five lobes per antimere, and an average size of 0.49cm length, 0.12cm width, and 0.05cm thick and average weight of 0.076g.

Distribuição configurada pela artéria celíaca em papagaios-verdadeiros (Amazona aestiva) / Configured distribution of the celiac artery in blue-fronted amazon (Amazona aestiva)

Foram descritas a origem e a distribuição da artéria celíaca em 20 papagaios-verdadeiros (Amazona aestiva), por meio do preenchimento do sistema arterial com solução de látex corado, fixado em solução de formol, para posterior dissecação de seus ramos colaterais. Como primeiro ramo, a artéria célica emitiu a artéria proventricular dorsal, que seguiu para o ventrículo como artéria gástrica dorsal e, em seguida, enviou a artéria proventricular ventral, que em 85 por cento dos exemplares se originou diretamente da artéria celíaca, ou do seu ramo esquerdo em 15 por cento. Em 25 por cento dos casos, a artéria esplênica foi emitida antes da bifurcação em ramo esquerdo e direito. O ramo esquerdo foi responsável pela origem de ramos proventriculares, ramos pilóricos, artéria esplênica e artéria proventricular ventral, a qual emitiu ramos ao proventrículo e ao esôfago. A artéria celíaca também originou as artérias gástrica ventral e gástrica esquerda, que foram responsáveis pela emissão da artéria hepática esquerda. O ramo direito emitiu artérias esplênicas - que variaram de uma a sete -, duodenal - destinada ao segmento mais caudal da alça ascendente do duodeno, hepática direita - para o lobo direito do fígado. Em seu segmento terminal, o ramo direito dividiu-se em artérias gástrica direita - para o ventrículo -, pancreaticoduodenal - para o pâncreas, alças ascendente e descendente do duodeno e segmentos cranial do íleo e caudal do jejuno. A irrigação determinada pela artéria celíaca nos papagaios segue o que é proposto para aves de outros gêneros, apresentando divergências como ausência das artérias vesicular e ileocecal, bem como da vesícula biliar e ceco.

This research was performed aiming to describe the origin and the distribution of the celiac artery in 20 blue fronted amazon (Amazona aestiva), through the completion of their circulatory system with an aqueous solution of colored latex, followed by fixation in formol for later dissection of the collateral branches. The first branch emitted the proventricular dorsal artery that headed to the ventricle as gastric dorsal artery and next emitted the proventricular ventral artery which originated on the celiac artery in 85 percent of the cases and in 15 percent had its origin on the left branch of the celiac artery. In 25 percent of the cases the splenic artery was emitted before the bifurcation on left and right branches. The left branch was responsible for the origin of the proventricular branches, piloric branches, splenic artery and proventricular artery, which emitted branches to the proventricle and esophagus. The celiac artery also emitted the gastric ventral artery and left gastric. The right branch emitted splenic arteries (that varied from a number of seven); duodenal bound for the more caudal segment of the ascendant segment of the duodenum and the right hepatica to the right liver lobe. On its terminal segment the right branch was divided into right gastric arteries to the ventricle and pancreaticduodenal to the pancreas, ascendant and descendant braces of the duodenum and to the cranial segments of the ileum and caudal of the jejune. The irrigation provided by the celiac artery in parrots remains the same as described for other bird genders showing as divergences: the lack of vesicular arteries and ileocecal as well the gall bladder and the cecos.

Parâmetros eletrocardiográficos de equinos desclassificados por exaustão em competições de enduro / Electrocardiographic parameters of horses disqualified from exhaustion in endurance competitions

Foram examinados, por meio de eletrocardiografia, 14 equinos Puro Sangue Árabe, 12 machos e duas fêmeas, desclassificados por exaustão em provas de enduro entre 60 e 160km. Foi observado predomínio de taquicardia sinusal, seguido de arritmia sinusal e complexo atrial prematuro com a frequência cardíaca variando de 48 a 78bpm e 93 a 111bpm, respectivamente. Ocorreu aumento da amplitude das ondas P, R, S e T e redução nas suas durações, bem como redução nos intervalos e segmentos, porém o complexo QRS quase não se alterou. O alongamento observado do QTc indicou fadiga miocárdica moderada em resposta ao exercício, e o supradesnível ST foi indicativo de hipovolemia. O eixo elétrico no plano frontal apresentou desvio à direita, aumento de câmara e hipertrofia secundários ao treinamento.

By using electrocardiographic examination, 14 Purebred Arabian horses, 12 males and two females, disqualified due to exhaustion in endurance races from 60 and 160km were evaluated. Predominance of sinus tachycardia, followed by sinus arrhythmia and atrial premature complex, with the heart rate ranging from 48 to 78bpm, and 93 to 111bpm, respectively, were observed. There was increase in the amplitude of waves P, R, S, and T, and decrease in their durations, as well as reduction in the intervals and segments; nevertheless, the QRS complex was not almost altered. The QTc lengthening pointed to a moderate myocardial fatigue in response to exercise, and the elevation of ST was indicative of hypovolemia. The electrical axis in frontal plane presented deviation to the right, chamber increase, and hypertrophy secondary to training.

Topografia do cone medular em gatos sem raça definida / Topography of the medullar cone in the domestic non-defined breed cat

Estudou-se a topografia post mortem do cone medular em 30 gatos adultos sem raça definida. Procedeu-se à remoção da pele e da musculatura dorsal da coluna vertebral e expuseram-se a medula espinhal e seus envoltórios, após a secção dos arcos vertebrais. O cone medular foi evidenciado e mensurado. Avaliou-se a sua relação com as vértebras lombares (L), sacrais (S) e caudais (Cd). O cone medular variou de 3,40 a 8,00cm (média=5,08cm). A esqueletopia foi variável, pois em 24 (80 por cento) animais o cone medular iniciou-se na vértebra L6; em quatro (13,3 por cento), na L7; e em dois (6,7 por cento), na L5. Em 12 (40 por cento) animais terminou na vértebra S2; em 10 (33,3 por cento), na S3; em cinco (16,7 por cento), na Cd1; em dois (6,7 por cento), na S1; e em um (3,3 por cento) na Cd2.

It was studied the post mortem topography of the medullar cone in 30 adult non-defined breed cats. The dorsal skin and muscles from the vertebral column were removed and the spinal cord and its wrappers were visualized, after the section of the vertebral arcs. The medullar cone was then exposed and measured. Its relationship with lumbar (L), sacral (S), and caudal (Cd) vertebrae was determined. The length of the medullar cone presented a variation from 3.40 to 8.00cm (average 5.08cm). Its skeletopy was variable; since in 24 animals (80 percent), the medullar cone began at the L6 vertebra; in four (13.3 percent), at the L7; and in two (6.7 percent) at the L5 vertebra. It ended in 12 (40 percent) animals at the S2 vertebra; in 10 (33,33 percent), at the S3; in five (16.7 percent) at the caudal (Cd) vertebra; in two (6.7 percent), at the S1; and in one (3.3 percent), at the Cd2.