A Spontaneous Melanocytic Iris Melanoma in a Rabbit (Oryctolagus cuniculus Linnaeus, 1758) Ana Caroline Freitas Caetano de Sousa, Wanderson Lucas Alves dos Santos, Ana Caroline Souza Maia, Arthur Vinícius Caetano de Oliveira, João Augusto Rodrigues Alves Diniz, Thalita Evani Silva de Oliveira, Radan Elvis Matias de Oliveira, Moacir Franco de Oliveira, Juliana Fortes Vilarinho Braga, Jael Soares Batista, Carlos Iberê Alves Freitas Veterinary Ophthalmology, 2026 This report describes the clinical, gross, histopathological, immunohistochemical, and therapeutic aspects of a spontaneous melanocytic iris melanoma in a rabbit, representing the first documented case of this condition in the species in the semiarid region of the state of Rio Grande do Norte, Brazil. A 2‐year‐old, mixed‐breed female rabbit was referred to the Wildlife Department presenting an inadequate diet based on food intended for human consumption. According to the anamnesis, the patient had previously received ocular treatment but later developed bleeding in the right eye. On ophthalmic clinical examination, there was active hemorrhage and ocular rupture, leading to an indication for surgical enucleation. A transpalpebral enucleation was performed, and the eyeball was fixed in 10% buffered formalin and submitted for histopathological evaluation. Histopathological analysis revealed a moderately cellular, unencapsulated, and poorly demarcated neoplasm of the iris and ciliary body, composed of spindloid and anaplastic melanocytic cells containing brown granular pigment, with 12 mitotic figures observed in 2.37 mm 2 . For immunohistochemical evaluation, melanin bleaching was performed, and a melanoma cocktail (HMB‐45, Melan‐A/MART‐1, and Tyrosinase) along with the proliferation marker Ki‐67 was used. The neoplastic cells showed diffuse cytoplasmic immunoreactivity for all melanocytic markers and nuclear labeling for Ki‐67, with a nuclear proliferation index of 38%, confirming the diagnosis of melanocytic iris melanoma. Excision of the eyeball using the transpalpebral technique was effective in the treatment of this neoplasm, providing a favorable prognosis. This case highlights the importance of considering iris melanoma as a differential diagnosis for ocular lesions in rabbits.
Ultrasonographic Ocular Biometry of the Greater Caribbean Manatee (Trichechus manatus manatus) Radan Elvis Matias de Oliveira, Fernanda Loffler Niemeyer Attademo, Rita de Kássia Matias de Oliveira, Romário Parente dos Santos, Fábia de Oliveira Luna, Antonio A. Mignucci‐Giannoni, Lesly J. Cabrias‐Contreras, Fabrício Bezerra de Sá, Flávio José de Lima Silva, Augusto Carlos da Bôaviagem Freire, Moacir Franco de Oliveira Veterinary Ophthalmology, 2026 This study aimed to characterize the ocular biometry of the Trichechus manatus manatus applying B‐mode ultrasonography across different age groups. Twenty‐two animals were assessed employing a portable ultrasound device equipped with a linear transducer. Five ocular parameters were assessed: corneal thickness (CT), anterior chamber depth (ACD), axial lens length (ALL), vitreous chamber depth (VCD), and axial globe length (AGL). Data were statistically analyzed at a 5% significance level based on normality and variance. The mean values (cm) for the right eye of calves, juveniles, and adults were, respectively, CT (0.082 ± 0.012; 0.088 ± 0.011; 0.091 ± 0.010), ACD (0.040 ± 0.005; 0.051 ± 0.008; 0.052 ± 0.007), ALL (0.345 ± 0.028; 0.367 ± 0.016; 0.414 ± 0.020), VCD (1.137 ± 0.076; 1.155 ± 0.062; 1.161 ± 0.089), and AGL (1.606 ± 0.098; 1.663 ± 0.071; 1.720 ± 0.094). Values for the left eye were CT (0.082 ± 0.012; 0.088 ± 0.012; 0.087 ± 0.011), ACD (0.041 ± 0.008; 0.048 ± 0.006; 0.052 ± 0.007), ALL (0.345 ± 0.028; 0.381 ± 0.027; 0.411 ± 0.025), VCD (1.147 ± 0.076; 1.174 ± 0.045; 1.166 ± 0.086), and AGL (1.617 ± 0.086; 1.693 ± 0.062; 1.717 ± 0.095). CT, VCD, and AGL were similar across age groups, while ACD and ALL increased with age. Positive correlations between body length and ocular parameters were significant only in calves. Ocular ultrasonography is, thus, an effective, safe, and reproducible tool for ophthalmic evaluations in T. m. manatus .
Metal(loid) Concentrations in Coastal (Sotalia guianensis) and Oceanic (Pseudorca crassidens) Odontocete Cetaceans Stranded Along the Northeastern Brazilian Equatorial Margin Rysónely Maclay de Oliveira, Radan Elvis Matias de Oliveira, Rachel Ann Hauser-Davis, Fernanda Loffler Niemayer Attademo, José Lailson Brito, Bárbara Manhães Moura Reis, Ana Bernadete Lima Fragoso, Flávio José de Lima Silva Biological Trace Element Research, 2026 Cetaceans face multiple threats, and pollution has become a major concern for their conservation worldwide. This study assessed metal(loid) concentrations in the tissues of two odontocete species with coastal and oceanic habits, namely Guiana dolphin ( Sotalia guianensis ; n = 11) and the false killer whale ( Pseudorca crassidens ; n = 8), respectively, stranded along the northeastern Brazilian equatorial margin. Silver (Ag), copper (Cu), cadmium (Cd), mercury (Hg), and selenium (Se) were determined in samples of liver, muscle, and kidney, expressed as mean ± standard deviation (SD), in µg g⁻¹ wet weight. In P. crassidens , Hg was detected in all individuals, with hepatic concentrations (794.1 ± 556.9 µg g⁻¹) higher than those in muscle (30.2 ± 16.7 µg g⁻¹); females exhibited higher levels than males in both tissues. In S. guianensis , mean Hg levels were also higher in the liver (1.6 ± 2.4 µg g⁻¹) compared to muscle (0.4 ± 0.4 µg g⁻¹), with the highest concentration detected in the kidney (3.1 µg g⁻¹). Detectable Cd concentrations occurred only in one juvenile (0.3 µg g⁻¹, liver). For Cu, Ag, and Se, values varied between species and tissues. The observed differences between species, as well as among sexes, age classes, and tissues, suggest that physiological factors, diet, and exposure time influence metal accumulation. These findings highlight the importance of considering the role of coastal versus oceanic habitat use, trophic ecology, and life history in the bioaccumulation of metal(loid)s since some of these factors were not assessed (i.e., trophic ecology).
The Morphology of the Tongue in the Spinner Dolphin (Stenella longirostris) Mariana Almeida Lima, Radan Elvis Matias de Oliveira, Fernanda Loffler Niemayer Attademo, Antonio Lopes da Silva Neto, Isadora Raquell Soares de Queiroz, Euziele Oliveira de Santana, Rysónely Maclay de Oliveira, Stella Almeida Lima, Flávio José de Lima Silva, Simone Almeida Gavilan, Ana Bernadete Lima Fragoso, Moacir Franco de Oliveira Journal of Veterinary Medicine Series C Anatomia Histologia Embryologia, 2026 Assessments of the tongue morphology contribute to the understanding of evolutionary processes associated with food and feeding habits. In this sense, this study aimed to describe the tongue morphology in the Spinner dolphin ( Stenella longirostris ) and understand possible morphological associations with its food and feeding habits. Macroscopic dissections and light as well as scanning electron microscopy analyses of three Spinner dolphin tongues were performed. The tongues are elongated and exhibit a dorsal surface divided into three regions, namely the apex, the body and the root. Two types of lingual papillae, marginal and vallate papillae, were identified. Microscopically, the tongue is composed of a Tunica mucosa and a muscle layer, the Musculus lingualis proprius . The epithelial lining of the Tunica mucosa is a cornified stratified squamous epithelium. No taste buds were found in any of the identified lingual papillae. The Lamina propria mucosae is formed by loose and dense connective tissue and contains compound tubuloacinar glands with serous and mucous cells and the excretory ducts open on the lingual surface. Serous cells were positively stained by PAS, whereas mucous glands were positively stained by Alcian blue. The muscle layer is composed of striated muscle with longitudinal, transverse, and oblique bundles. Thus, Spinner dolphin tongues are similar to those of other odontocetes with only two types of lingual papillae and many lingual glands. Taste buds are absent. Based on the morphology, we hypothesize that the main function of the tongue in the Spinner dolphin is to aid in swallowing whole prey.
An intestinal histiocytic sarcoma in a collared peccary (Pecari tajacu): a case report Jael Soares Batista, Radan Elvis Matias de Oliveira, Wanderson Lucas Alves dos Santos, Ana Caroline Freitas Caetano de Sousa, Igor Renno Guimarães Lopes, João Augusto Rodrigues Alves Diniz, Thalita Evani Silva de Oliveira, Robério Gomes Olinda, Erick Platini Ferreira de Souto, Moacir Franco de Oliveira Acta Veterinaria Scandinavica, 2025 Background Research on cancer in wild animals provides important insights into the mechanisms of carcinogenesis. Histiocytic sarcomas comprise a rare malignant macrophage-dendritic cell lineage neoplasm in wildlife. This study reports a case of histiocytic sarcoma in the small intestine of a collared peccary ( Pecari tajacu ), describing its clinical, anatomopathological, and immunohistochemical aspects. Case presentation A six-year-old male collared peccary maintained in captivity at a facility in Northeastern Brazil presented progressive weight loss, diarrhea, anorexia, dyspnea, lethargy, abdominal distension, bristled fur, and pale mucous membranes. A complete blood count indicated a mild degree of anemia and moderate leukocytosis. Treatment included anti-inflammatories and antibiotics; however, on the 18th day after initial presentation, the animal was found dead in its enclosure. An anatomopathological examination revealed that the animal exhibited poor body condition, scant body fat with a gelatinous appearance, hydrothorax, pulmonary edema, and ascites. Thickening of the duodenal wall was observed, along with the presence of a yellowish-white tumor. Histopathological examination of the affected intestinal segment revealed a neoplastic proliferation of round cells with large, hyperchromatic nuclei, prominent nucleoli, and a high mitotic index (20 mitoses per high-power field). Numerous multinucleated and binucleated giant cells were present. The neoplastic cells extensively infiltrated all layers of the intestinal wall, from the mucosa to the serosa. Immunohistochemical analysis showed strong positivity for macrophage/mononuclear phagocytic lineage markers (CD18, IBA-1, and lysozyme), while negative for T-cell (CD3), B-cell (CD79), and plasma cell (MUM1) markers. The proliferation index assessed by Ki-67 was approximately 60%. Conclusions The histopathological and immunohistochemical findings confirmed the diagnosis of intestinal histiocytic sarcoma in a collared peccary, representing the first documented case of this neoplasm in this species.
Large vaginal calculus in a red-rumped agouti (Dasyprocta leporina) Radan Elvis Matias de Oliveira, Isadora Raquell Soares de Queiroz, Fernanda Loffler Niemeyer Attademo, Ana Caroline Freitas Caetano de Sousa, João Augusto Rodrigues Alves Diniz, Jael Soares Batista, Moacir Franco de Oliveira Journal of Comparative Pathology, 2025
The Role of Skin-Derived Somatic Cell and Tissue Cryobanks in the Conservation of Aquatic Mammals Luanna Lorenna Vieira Rodrigues, Radan Elvis Matias de Oliveira, Fernanda Löffler Niemeyer Attademo, Alexsandra Fernandes Pereira Biopreservation and Biobanking, 2025 Anthropogenic actions, especially inadequate waste disposal, cause permanent effects on aquatic fauna, resulting in a significant loss in their population. In this scenario, in situ and ex situ conservation strategies have been developed for these species. Among these strategies is the formation of somatic cell and tissue banks derived from skin collection that act complementarily to other biotechnologies. These banks contain all the information for genomic, genetic, and proteomic analyses. They are useful in the assessment of the toxicity of pollutants on the physiology of the species and regenerative and reproductive biotechnologies. The formation of these cryobanks involves different steps, including cryopreservation, with the optimization of all steps occurring in a species-specific manner. There is a diversity of studies on aquatic mammals; however, a low quantity compared to the number of studies on land mammals, with more than 80% of species still unexplored. This is mainly due to the difficulty of execution and asepsis in collecting skin from aquatic mammals and the in vitro culture, which seems to require more particularities for it to be successful. Therefore, this review aims to address the current scenario and the steps involved in the conservation of somatic cells and tissues derived from aquatic mammal skin, as well as results that have been achieved in recent years and the prospects.
Dietary L-arginine for sows minimises the variability of piglets at birth Rennan Herculano Rufino Moreira, Pedro Henrique da Silva Fidelis, Cesar Augusto Pospissil Garbossa, Leonardo da Silva Fonseca, Marilane das Dôres Silva, Radan Elvis Matias de Oliveira, Camilla Mendonça Silva, Rôny Antônio Ferreira, Vinicius de Souza Cantarelli, Márvio Lobão Teixeira de Abreu Journal of Agricultural Science, 2025 The objective of the trial was to evaluate the effects of arginine supplementation in the feed of gestating sows on the variability of piglet birth weight. The weight of the piglets was evaluated using descriptive analysis, correlation analysis and analysis of variance with a 2 × 3 factorial arrangement. This arrangement included no supplementation or supplementation with 1.0 % L-arginine, combined in three periods. Period 1: from days 25 to 53 of gestation, providing 23 g/day from days 25 to 28 and 18 g/day from days 29 to 53 of gestation; period 2: from days 30 to 60 of gestation and from day 80 of gestation to farrowing, providing 18 g/day in the first period and 45 g/day in the second period and period 3: from day 85 of gestation to delivery, with 24 g/day was provided from day 85 until farrowing and 28 g/day from days 85 to 107, increasing to 56 g/day from day 108 until farrowing. Supplementation with 1.0 % of L-arginine reduced the percentage of total piglets born and piglets born alive with less than 800 g by 2.26 and 2.05 percentage points, respectively; and increased the percentage of total piglets born and piglets born alive between 1601 and 1800g by 5.89 and 6.08 percentage points, respectively. Supplementing with 1.0 % of L-arginine improves litter uniformity, with an average reduction of 4.06 percentage points in the piglet population of less than 1180 g and an increase in the piglet population of 1180 to 1890 g by 4.70 percentage points.
Capybara (Hydrochoerus hydrochaeris) Salivary Glands Morphology Flavia María Pía Montenegro Donoso, Marilú Cristofoli, Daniel Vitor Matos Lobão, Fernanda Batistella Passos Nunes, Fabiana Morse Gosson Jorge, Mayla Magalhães de Oliveira Alcobaça, Radan Elvis Matias de Oliveira, Antônio Chaves de Assis Neto Journal of Veterinary Medicine Series C Anatomia Histologia Embryologia, 2024
Prenatal post-implantation development of collared peccaries (Pecari tajacu Linnaeus, 1758) Hélio Noberto de Araújo Júnior, Igor Renno Guimarães Lopes, Ana Caroline Freitas Caetano de Sousa, Gleidson Benevides de Oliveira, Radan Elvis Matias de Oliveira, Moisés Dantas Tertulino, Emanuel Lucas Bezerra Rocha, Paulo Ricardo Firmino, Alexsandra Fernandes Pereira, Moacir Franco de Oliveira Journal of Veterinary Medicine Series C Anatomia Histologia Embryologia, 2024
Morphology of the major salivary glands of Spix's Yellow-Toothed Cavys (Galea spixii Wagler, 1831) Carlos Eduardo Vale Rebouças, João Augusto Rodrigues Alves Diniz, Ana Caroline Freitas Caetano de Sousa, Radan Elvis Matias de Oliveira, Carlos Eduardo Bezerra de Moura, Ricardo Romão Guerra, Alexsandra Fernandes Pereira, Antônio Chaves de Assis Neto, Moacir Franco de Oliveira Acta Zoologica, 2024
Gonadal Morphology of Stillborn Hawksbill Sea Turtle (Eretmochelys imbricata) Hatchlings Emanuel Lucas Bezerra Rocha, Lucas Gabriel Verissimo Pinheiro da Silva, Isadora Natália Rocha Barreto, Marcela dos Santos Magalhães, Lucas Castanhola Dias, Radan Elvis Matias de Oliveira, Janine Karla França da Silva Braz, Moacir Franco de Oliveira, Carlos Eduardo Bezerra de Moura Microscopy and Microanalysis, 2024
Antillean manatee (Trichechus manatus manatus Linnaeus, 1758) Tongue Morphology and Adaptive Herbivorous Implications Lucas Inácio dos Santos Melo, Radan Elvis Matias de Oliveira, Ana Caroline Freitas Caetano de Sousa, Rysónely Maclay de Oliveira, Mariana Almeida Lima, Ana Bernadete Lima Fragoso, Flávio José de Lima Silva, Fernanda Loffler Niemeyer Attademo, Fábia de Oliveira Luna, Alexsandra Fernandes Pereira, Moacir Franco de Oliveira Microscopy and Microanalysis, 2024
Abdominal aortic branches of red-rumped agouti (Dasyprocta leporina Linnaeus, 1758) Moisés Dantas Tertulino, Ana Caroline Freitas Caetano de Sousa, João Vitor de Oliveira Gurgel, Igor Renno Guimarães Lopes, João Augusto Rodrigues Alves Diniz, Valéria Veras de Paula, João Marcelo Azevedo de Paula Antunes, Radan Elvis Matias de Oliveira, Moacir Franco de Oliveira Journal of Veterinary Medicine Series C Anatomia Histologia Embryologia, 2023
Morphological tongue and palate characterizations in Trachemys adiutrix (Vanzolini, 1995) turtles Rafaella Sousa Ferraz, Lukas Allayn Diniz Corrêa, Margareth Cavalcante Ribeiro Calvet, Paula Maria Mesquita Santiago, Tiago da Silva Teófilo, Radan Elvis Matias de Oliveira, Adriano Luis Martins, Larissa Nascimento Barreto, Melaine Mont’Alverne Lawall Silva Journal of Veterinary Medicine Series C Anatomia Histologia Embryologia, 2023
Collateral aortic branches in the collared peccary (Pecari tajacu Linnaeus, 1758) João Vitor de Oliveira Gurgel, Ana Caroline Freitas Caetano de Sousa, Radan Elvis Matias de Oliveira, Moisés Dantas Tertulino, Igor Renno Guimarães Lopes, João Marcelo Azevedo de Paula Antunes, João Augusto Rodrigues Alves Diniz, Carlos Eduardo Bezerra de Moura, Moacir Franco de Oliveira Journal of Veterinary Medicine Series C Anatomia Histologia Embryologia, 2022
Rehabilitation of loggerhead turtle (Caretta caretta Linnaeus, 1758) after head trauma Amy Borges Moreira, Fernanda Löffler Niemeyer Attademo, Radan Elvis Matias Oliveira, Lucas Inácio Santos Melo, Marcus Arthur Marques Dantas, Augusto Carlos da Bôaviagem Freire, Juliana Maia de Lorena Pires, Heloisa Cristina Morais e Sá Leitão, Iara Cecília da Costa Morais, Flávio José de Lima Silva Medicina Veterinaria Brazil, 2021
Pathoanatomical findings of a green turtle (Chelonia mydas) victim of collision with a motorboat Radan Elvis Matias De Oliveira, Fernanda Loffler Niemeyer Attademo, Augusto Carlos Da Bôaviagem Freire, Juliana Maia De Lorena Pires, Daniel Solon Dias De Farias, Aline Da Costa Bomfim, Rysónely Maclay De Oliveira, Simone Almeida Gavilan, Flávio José De Lima Silva, Moacir Franco De Oliveira Acta Veterinaria, 2021
Intussusception Associated with Sand Accumulation in a Greater Rhea (Rhea americana) Jael Soares Batista, Moacir Franco de Oliveira, Tiago Da Silva Teófilo, Ana Caroline Freitas Caetano De Sousa, Wanderson Lucas Alves Dos Santos, Igor Renno Guimarães Lopes, Ana Indira Bezerra Barros Gadelha, Moisés Dantas Tertulino, João Vitor de Oliveira Gurgel, Radan Elvis Matias de Oliveira Acta Veterinaria, 2021
Brucella Infection Investigation in Cetaceans and Manatees in Northeast Brazil Gláucia Pereira Sousa, Rodrigo Martins Soares, João Carlos Gomes Borges, Ana Paula Domingos Brito, Daniella Carvalho Ribeiro Oliveira, Thalita Faita, Fernanda Loffler Niemeyer Attademo, Fábia de Oliveira Luna, Radan Elvis Matias de Oliveira, Carlos Iberê Alves Freitas, Jociery Einhardt Vergara‐Parente, Lara Borges Keid Journal of Aquatic Animal Health, 2021
Pyothorax in Antillean Manatee (Trichechus manatus) in Brazil Fernanda Löffler Niemeyer Attademo, Fábia De Oliveira Luna, Glaucia Pereira de Sousa, Augusto Carlos da Bôaviagem Freire, Deisi Cristiane Balensiefer, Radan Elvis Matias de Oliveira Acta Scientiae Veterinariae, 2020
Morphology and anatomic-surgical segmentation of the spleen of pecari tajacu Linnaeus, 1758 Gleidson Benevides de Oliveira, Felipe Venceslau Câmara, Ferdinando Vinícius Fernandes Bezerra, Hélio Noberto de Araújo Júnior, Radan Elvis Matias de Oliveira, Herson da Silva Costa, Amilton Cesar Santos, Carlos Eduardo Bezerra de Moura, Moacir Franco de Oliveira Bioscience Journal, 2018
Arterial vascularization of the brain of the agouti (Dasyprocta aguti Linnaeus, 1766) Universidade Federal Rural do Semi-Árido, Roberto Sávio Bessa da Silva, Gleidson Benevides de Oliveira, Universidade Federal Rural do Semi-Árido, Carlos Magno Oliveira Junior, Universidade Federal Rural do Semi-Árido, Ferdinando Vinicius Fernandes Bezerra, Universidade Federal Rural do Semi-Árido, Felipe Venceslau Câmara, Universidade Federal Rural do Semi-Árido, Radan Elvis Matias de Oliveira, Universidade Federal Rural do Semi-Árido, Moacir Franco de Oliveira, Universidade Federal Rural do Semi-Árido, Universidade Federal Rural do Semi-Árido Semina Ciencias Agrarias, 2016
