Abstract Recent studies showed that vision and hearing in dolphins are mechanisms for perception of the environment, and transmission of information among individuals. Considering that Guiana dolphins (Sotalia guianensis) are distributed in costal regions, and Clymene dolphins (Stenella clymene) are found in oceanic environments, the objective of this study was to compare the morphology of the eyes of these two species, assessing the differences in eye structures in both environments. Five specimens of Sotalia guianensis and four specimens of Stenella clymene were analyzed. All the specimens were found stranded in the northeastern coast of Brazil. Samples were fixated in 10% formaldehyde, dissected, photographed, processed, and analyzed by optical microscopy. The inferior palpebral region of the two species showed a granular layer, subcutaneous lymphoid tissue, and innervation. Morphometric values of the eyelid structures and eye bulb were greater in S. clymene. The cornea showed four layers in S. clymene: anterior epithelium, anterior lamina, stroma, and posterior lamina. The sclera of S. guianensis showed more melanocytes and presence of mechanoreceptors next to the Harderian gland. It is possible to suggest that the geographical distribution of these cetaceans determine their eye morphology, which is an adaptation to the intrinsic characteristics of the aquatic environment.

Abstract The roadside hawk (Rupornis magnirostris) is a free-living bird that commonly has wing injuries caused by man-made obstacles when flying. Studies that describe the topographic anatomy of the wings of this species are necessary to assist in the treatment of possible wing lesions. For this reason, the present work aimed to describe the origin and insertion of the nerves that constitute the brachial plexus in roadside hawks. Five roadside hawk carcasses donated to the Animal Anatomy Laboratory of the São Judas University Center, UNIMONTE campus, by CEPTAS (Center for Research and Screening of Wild Animals) were used for the study. The brachial plexus of the roadside hawk was formed by the union of the ventral branches of the spinal nerves located between C9-C10-T1-T2-T3. The ventral branches joined together and formed four short trunks which later united again by exchanging nerve fibers and constituting a big caliber branch. This is divided into two nerve cords (dorsal and ventral) which are destined to specific muscular groupings. The dorsal cord originates the axillary, anconeal and radial nerves, and is responsible for innervating the extensor muscles. The ventral cord originates the pectoral, bicipital, median-ulnar, median and ulnar nerves, and is responsible for innervating the flexor muscles.

A morfologia reprodutiva dos cetáceos é pouco estudada e, apesar do grande número de encalhes, dados sobre este assunto são escassos principalmente devido ao acesso às carcaças em um estado avançado de decomposição. O presente estudo teve como objetivo descrever as características histológicas dos órgãos reprodutores femininos de Sotalia guianensis, auxiliando futuros estudos sobre a biologia reprodutiva desses animais. Fêmeas de diferentes idades foram utilizadas, oriundas de eventos de encalhe em praias no nordeste do Brasil. Fragmentos de todos os órgãos foram coletados e processados para microscopia de luz e eletrônica de varredura. As análises histológicas mostraram que estas estruturas eram semelhantes às encontradas em mamíferos terrestres, com algumas particularidades, tais como a presença de células diferenciadas na camada subepidermal vulvar, não descritos na literatura de cetáceos. Os estudos de reprodução com uma descrição morfológica dos órgãos reprodutores femininos são extremamente importantes, uma vez que podem fornecer uma compreensão melhor da fisiologia reprodutiva da espécie, auxiliando no desenvolvimento de novas estratégias para sua conservação.

The reproductive morphology of cetaceans is poorly studied and, despite the large number of strandings, reports on this subject are scarce due to access to carcasses mostly in an advanced state of decomposition. The present study aimed to describe histological characteristics of the female genital tract ofSotalia guianensis, in order to assist in future studies on the reproductive biology of these animals. Females of different ages, from stranding events on beaches in northeastern Brazil, were used. Fragments of all organs were collected and processed for light and scanning electron microscopy. Histological analyses showed that these structures were similar to those found in terrestrial mammals, with some peculiarities, such as the presence of differentiated cells in the vulvar subepidermal layer, not described in the literature on cetaceans. Reproductive studies with a morphological description of the female genital organs are extremely important, since they would enable a better understanding of the species reproductive physiology and assist in the development of new strategies for the species conservation.

Foram estudados corpúsculos de Herbst da mucosa palatina de avestruz em nível de microscopia de luz. Os corpúsculos compõem-se de uma cápsula externa, cápsula interna e axônio central. A cápsula externa apresentou numerosas lamelas, enquanto que a cápsula interna mostrou estrutura de folhas compactas. Os corpúsculos apresentaram formato ovalado ou circular e circundado por espessos feixes de fibras colágenas. Cada lamela estava composta de uma densa rede de fibras espessas. Os axônios terminais estavam situados ao longo do eixo, terminando em um bulbo terminal. As fibras da cápsula externa, coradas por Picrosirius e examinadas no microscópio óptico sob luz polarizada, revelou a presença de fibras colágenas do tipo I em verde e na região periférica observou-se grande quantidade de fibras colágenas do tipo III. Os corpúsculos apresentaram-se envoltos por células planas e envoltos por fibras colágenas.

Herbst corpuscles of the palatine mucosa of ostrich were studied by light microscopy. The corpuscles are composed of an outer core, inner core and central nerve terminal. The outer core presents numerous lamellae, while the inner core shows compact structure of cytoplasm sheets. The corpuscles are elongate or oval in shape and are surrounded by bundles of collagen fibers. Each lamella is composed of a dense network of thick fibrils. The terminal axons are located along the axis and form a bulb terminal. The fibers of external core stained by Picrosirius and examined by polarized light microscopy revealed to be green in color like type I collagen fibers, and at the periphery is a large amount of collagen type III. The corpuscles are surrounded by flat cells and dense collagen fibers at the periphery.

As características tridimensionais dos componentes intracelulares de células acinares e de ductos foram reveladas usando o método ósmio-DMSO-ósmio. As amostras foram maceradas em solução de tetróxido de ósmio diluído após a fratura na solução de dimetil sulfoxido. As lamelas do retículo endoplasmático granular são reveladas entremeadas por várias mitocôndrias. As lamelas do retículo endoplasmático granular são localizados ao redor dos núcleos na porção basal e estas estruturas são observadas em imagens tridimensionais de microscopia eletrônica de alta resolução.

The three-dimensional characteristics of the intracellular components of acinar and ductal cells were revealed using the osmium-DMSO-osmium method. The samples were macerated in diluted osmium after fractured in DMSO solution. The stacks of the rough endoplasmic reticulum are revealed intermingling by several mitochondria. The lamellae of the rough endoplasmic reticulum are located around the nuclei at basal portion and these structures are shown in three-dimensional HRSEM images.