Anteater forelimbs are morphologically adapted to obtain food and to provide defense and locomotion. Four species are known, but there are few anatomical studies presenting the morphologic features of each species. The aim of this study was to describe the skeletal morphology of the giant anteater (Myrmecophaga tridactyla) forelimb. Pictures and schematic drawings of six cadavers were created to show the bone morphology. In addition, radiographs and computed tomographs were obtained. The skeletal structure of the forelimb had several notable anatomical features. The scapula had two spines, with apparent differences between infant and adult animals. The humerus had a pectoral ridge, a pectoral tubercle, and a pronounced medial epicondyle that represent the origins of muscles important for fossorial activity. The radius had cranial, lateral, and caudal ridges that became more prominent in older animals, and the distal condyle joint provided enhanced support of the dorsal articulation for the manus. Knowledge of the bone morphology of the forelimb generates a better understanding of giant anteater habits and helps in the diagnosis of skeletal abnormalities and in the routine medical assessment of this species.

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In this study, we associated imaging modalities, such as computed tomography (CT) and standard radiography, with anatomical specimens to describe the anatomy of the appendicular skeleton of red-footed tortoises (Chelonoidis carbonaria), using animals of different sizes, ages, sexes and weights. Manus and pes bones were described from conventional radiography and osteological specimens, because they have small structures that could not be reconstructed. The main anatomical feature that differentiates C. carbonaria from others Testudines is the ischial-pubic tuberculum. The pectoral girdle is formed by the union of two bones, the scapula and the coracoid, showing no bone connection with the shell. Carpal and tarsal bones can be fused or not and include: carporadial and central carpus, carpoulnar and V carpal, central tarsal and fibular tarsal, distal tarsal I and II. The phalangeal formula is 2:2:2:2:2 in the forelimb and 2:2:2:2:1 in the hind limb. Imaging examinations are important tools in anatomical description and can be used in living individuals, replacing or aiding the study with anatomical specimens.

Anteater forelimbs are distinguished morphologically from domestic animals, especially due to their unique movement and their natural habits. A knowledge of the pectoral limb anatomy and the proper surgical approach are fundamental to success in osteosynthesis and other surgeries. This study aimed to describe the muscles and neurovascular structures of the pectoral limb and the surgical approach to the humeral shaft of the giant anteater ( Myrmecophaga tridactyla ). Dissections of the forelimbs of seven cadavers were performed to identify the major muscles and neurovascular structures. Three of these animals' contralateral forearms were used to simulate the surgical approach to the humeral shaft. Some specific characteristics of the muscle morphology were biceps muscle had two heads, triceps muscle had three heads, and there was an olecranon-epicondylar muscle. To expose the shaft of the humerus, it was necessary to incise the superficial pectoral muscle and separate the heads of the biceps muscle. Due to the anatomical characteristics of the humerus, the craniomedial approach was the most appropriate because it accommodated the anatomical peculiarities of the giant anteater.

RESUMO: Este estudo teve como objetivo geral descrever os aspectos ultrassonográficos normais das estruturas do bulbo ocular de primatas da espécie Alouatta fusca, determinando ainda os valores da biometria ocular, e os parâmetros da dopplerfluxometria ocular das artérias oftálmica interna e central da retina. Vinte exames ultrassonográficos oculares foram realizados em dez primatas da espécie Alouatta fusca clinicamente saudáveis, sem sinais de doença ocular ao exame oftalmológico. Procedeu-se a descrição ultrassonográfica das estruturas oculares e posteriormente a biometria foi obtida em quatro distâncias distintas: (D1) correspondentes à câmara anterior, (D2) espessura da lente, (D3) profundidade da câmara vítrea e (D4) comprimento axial do bulbo ocular. Na dopplerfluxometria foram avaliadas as artérias oftálmica interna e central da retina quanto ao índice de resistividade (IR), de pulsatilidade (IP), e as velocidades do pico sistólico (VPS) ediastólica final (VDF). Os valores de biometria foram submetidos a teste de comparação quanto ao gênero dos animais e cortes ultrassonográficos, utilizando o teste t de Student. O mesmo teste foi realizado para comparação dos resultados de dopplerfluxometria entre fêmeas e machos. A descrição ultrassonográfica das estruturas oculares e vascularização do bugio ruivo mostraram-se semelhantes a espécies como o cão, o gato e o homem. Os valores biométricos médios encontrados foram de 2,1±0,38 mm para D1, 3,7±0,30mm para D2, 10,4±0,78mm para D3 e 19,3±1,64mm para D4. Os valores de dopplerfluxometria da artéria oftálmica e da artéria central da retina foram respectivamente: VPS de 25,6cm/s e 14,6cm/s; VDF de 15,8cm/s e 10,7cm/s; IR de 0,7 e 0,5; IP de 1,4 e 0,8.