Effect of Different Vitrification Techniques on Viability and Apoptotic Index of Domestic Cat Testicular Tissue Cells.

Vitrification is essential for successful tissue cryopreservation and biobanking in wild cats. This study aimed to compare different methods of vitrification (Ovarian Tissue Cryosystem-OTC, Straws-STW, and Solid Surface vitrification-SSV) for testicular fragment vitrification in tom cats. Testicular fragments were recovered from five adult tom cats and subjected to equilibrium vitrification using different cryovials and methods under the same conditions of vitrification solutions and cryoprotectants. The efficiencies of the methods were evaluated using histological analysis of spermatogonia and Sertoli cell nuclei, seminiferous tubular basement membrane detachment, and the gonadal epithelium shrinkage score scale. Cell viability was assessed using Hoechst PI and Terminal deoxynucleotidyl transferase nick end labeling (TUNEL) assay. The results showed that OTC is an effective vitrification method for maintaining the distinction between spermatogonia and Sertoli cells. OTC was similar to the control for basal membrane detachment parameters (p = 0.05). Epithelial shrinkage was low in the SSV group, which showed the highest percentage of viable cells among the vitrified groups (p = 0.0023). The OTC and SSV vitrification methods were statistically similar in terms of the percentage of TUNEL-positive cells (p = 0.05). Therefore, OTC and SSV provide favorable conditions for maintaining viable cat testicular tissue cells after vitrification.

Casuistry of xenarthrans treated at the Veterinary Hospital of the Federal University of Pará, Brazilian Amazon / Casuística de Xenarthras atendidos no Hospital Veterinário da Universidade Federal do Pará, Amazônia brasileira

ABSTRACT: The present study aimed to analyze the casuistry of xenarthrans treated at the veterinary hospital of the Federal University of Pará to quantify the most important cases for clinical care and identify the main species, sex, age group, origin, and destination of the animals admitted. The data were collected from January 2013 to August 2020. The variables analyzed were the number of animals by species, sex, age group, weight (kilograms), form of admission (rescue or guardianship), person responsible for the admission of the animal, origin, circumstances of admission, length of stay (days), and evolution or destination of the animal (release, captivity, death, euthanasia, or escape). Fisher's exact test was used to determine whether disease incidence was related to sex and whether animal mortality was influenced by sex and disease. The chi-square test was used to determine whether mortality differed by age group. Ninety-two (92) xenarthrans were included: 66 Bradypus variegatus, 10 Choloepus didactylus, 15 Tamandua tetradactyla, and one Dasypus novemcinctus. The animals were mainly from the municipality of Castanhal (70%) and were acquired through rescue (88%, B. variegatus; 80%, C. didactylus; 100%, T. tetradactyla), a significant proportion of which was per natural persons (88%, B. variegatus; 80%, C. didactylus; 100%, T. tetradactyla). The most important circumstances that led to the admission of the animals were as follows: animals for examination (42%, n=39), young animals at risk (9%, n=8), hit by a vehicle (8%, n=7), respiratory disease (7%, n=6), fall from a tree (5%, n=5), and electrotrauma (5%, n=5). Release was the most common destination of animals after hospitalization (59% B. variegatus, 50% C. didactylus, and 66% T. tetradactyla). The sex of the animals did not affect the incidence of disease or mortality in any species. In contrast, mortality of B. variegatus was significantly higher in animals admitted with disease (p=0.000). Mortality in cubs of this species was higher than that in juveniles and adults (p=0.003).

RESUMO: O objetivo deste trabalho foi analisar a casuística dos Xenarthras atendidos no Hospital Veterinário da Universidade Federal do Pará (UFPA), a fim de quantificar as principais ocorrências para atendimento clínico, identificar as principais espécies, o sexo, a faixa etária, a procedência e destinação dos animais recebidos. Os dados foram obtidos entre janeiro de 2013 a agosto de 2020. As variáveis analisadas foram número de animais por espécie, sexo, faixa etária, peso (quilogramas), forma de recebimento (resgate, tutela), responsável pelo encaminhamento do animal ao hospital, procedência, circunstância de admissão, tempo de internação (dias) e evolução ou destinação do animal recebido (soltura, cativeiro, morte, eutanásia, fuga). O teste de Fisher foi utilizado para avaliar se a ocorrência de doenças estava relacionada ao sexo, bem como se a mortalidade animal foi influenciada pelo sexo e por enfermidades. O teste Qui-quadrado foi utilizado para avaliar se a mortalidade diferiu em relação à faixa etária. Um total de 92 animais Xenarthras foi admitido, composto por 66 Bradypus variegatus, 10 Choloepus didactylus, 15 Tamandua tetradactyla e um Dasypus novemcinctus. Os animais foram procedentes principalmente do município de Castanhal (70%), sendo o resgate a principal forma de aquisição dos animais (88%, B. Variegatus; 80%, C. Didactylus; 100%, T. tetradactyla), realizado em maior parte por pessoa física (88%, B. Variegatus; 80%, C. Didactylus; 100%, T. tetradactyla). O sexo dos animais não influenciou a ocorrência de doenças ou mortalidade em nenhuma espécie. Por outro lado, a mortalidade de B. variegatus foi significativamente maior naqueles animais admitidos com alguma enfermidade (p=0,000). A mortalidade em filhotes desta espécie foi maior quando comparada com as categorias jovem e adulta (p=0,003).

Epididymal tail solid-surface vitrification as an effective method for domestic cat sperm cryobanking.

This study aimed to describe the viability of domestic feline spermatozoa after epididymal tail vitrification. For this, 10 pairs of testis-epididymis complexes were used. The epididymal tails were vitrified using the solid-surface vitrification (SSV) method, in which two vitrification media containing ethylene glycol (EG) 40% or glycerol (GLY) 40% were tested. Vitrification with the presence of EG resulted in better results for all sperm motility parameters (motility, vigour and CASA) compared with GLY (P < 0.05). There were no statistical differences for sperm viability and acrosome integrity, plasma membrane integrity, or overall health of morphologically normal sperm before or after vitrification among experimental groups. In conclusion, epididymal tail vitrification appears to be a suitable method for long-term storage of cat sperm, especially if the procedure is performed with EG as the cryoprotectant.