Kinetic vitrification: concepts and perspectives in animal sperm cryopreservation

Sperm cryopreservation is an important tool for genetic diversity management programs and the conservation of endangered breeds and species. The most widely used method of sperm conservation is slow freezing, however, during the process, sperm cells suffer from cryoinjury, which reduces their viability and fertility rates. One of the alternatives to slow freezing is vitrification, that consist on rapid freezing, in which viable cells undergo glass-like solidification. This technology requires large concentrations of permeable cryoprotectants (P- CPA's) which increase the viscosity of the medium to prevent intracellular ice formation during cooling and warming, obtaining successful results in vitrification of oocytes and embryos. Unfortunately, this technology failed when applied to vitrification of sperm due to its higher sensitivity to increasing concentrations of P-CPAs. Alternatively, a technique termed 'kinetic sperm vitrification' has been used and consists in a technique of permeant cryoprotectant-free cryopreservation by direct plunging of a sperm suspension into liquid nitrogen. Some of the advantages of kinetic vitrification are the speed of execution and no rate-controlled equipment required. This technique has been used successfully and with better results for motility in human (50-70% motility recovery), dog (42%), fish (82%) and donkey (21.7%). However, more studies are required to improve sperm viability after devitrification, especially when it comes to motility recovery. The objective of this review is to present the principles of kinetic vitrification, the main findings in the literature, and the perspectives for the utilization of this technique as a cryopreservation method.(AU)

Gincana anatômica - metodologia ativa no ensino-aprendizagem da Medicina Veterinária: relato de caso / Anatomy competition - active methodology in teaching-learning of Veterinary Medicine: case report

O presente trabalho descreve uma metodologia ativa para auxiliar o ensino-aprendizado na formação de profissionais mais capacitados e contribuir como modelo de estudo para alunos da disciplina de Anatomia Veterinária. A gincana foi realizada com a participação de alunos (n = 48) do primeiro semestre da Faculdade de Medicina Veterinária da Universidade Federal do Pará - Castanhal, no ano de 2018. A turma foi dividida nos grupos A e B, com 24 discentes em cada. O docente (mediador) informou as regras da atividade. Os representantes do grupo A foram alocados em cadeiras individuais de nº 1 a 24 em um lado da sala, o mesmo ocorreu para o grupo B, no lado oposto. A atividade foi iniciada pela dupla da cadeira nº 1 por grupo e finalizada pela dupla da cadeira nº 24. Cada dupla foi chamada pelo mediador da atividade a sentar nos dois bancos no centro da sala, e então foi realizado o ‘par ou ímpar’ com cada dupla para o vencedor escolher um balão pregado na parede da sala, estourar e direcionar o papel que estava no seu interior com as instruções da atividade a ser proposta pelo mediador. As atividades consistiam em 1) responder as perguntas, 2) realizar mímica e 3) participar da “caixa misteriosa”. As pontuações foram acerto (+) ou erro (-), conforme critérios preestabelecidos no papel no interior do balão. A utilização de MA despertou a curiosidade dos alunos, exigindo que eles adquirissem mais conhecimento para poder participar da atividade e apesar de haver restrições na análise de sua efetividade por se tratar apenas de aspectos extraídos da fala dos estudantes, a dinâmica educacional auxiliou no desenvolvimento de competências técnicas e humanísticas. A experiência realizada destaca a importância da difusão de técnicas ativas de ensino, especialmente, em instituições de ensino superior.

The aim of this study was the description of an active learning that can assist the teaching-learning process (TLP) in the formation of more qualified professionals, and to contribute as a study model for students of Veterinary Anatomy. A total of 48 first year students from the Faculty of Veterinary Medicine (Universidade Federal do Pará/Castanhal) participated in the game. The class was divided into groups A and B, with 24 students in each of them. The teacher (mediator) informed the rules of the activity. The representatives of group A were allocated individual chairs from number 1 to 24 on one side of the room, and the same occurred for group B on the opposite side. Each pair was called by the mediator to sit on two benches in the center of the room, and then a game of “odd or even” was played with each pair so that the winner could choose a balloon stuck on the wall of the room, pop it, and send the paper with the instructions of the activity to the mediator. The activities consisted of 1) answering the questions, 2) mimic, and 3) participate in the “mystery box”. The scores were hit (+) or error (-) according to pre-established criteria. The use of TLP aroused the students’ curiosity, demanding that they acquire more knowledge in order to participate in the activity. And although there are restrictions in the analysis of its effectiveness because it deals only with aspects extracted from the students’ speech, the educational dynamics helped in the development of technical and humanistic skills. Thus, the practice applied showed the importance of active learning techniques dissemination, mainly in higher education institutions.

Estudo preliminar da morfometria da cabeça espermática do macaco-de-cheiro de vida livre / Preliminary study of the spermatic head morphometry of free living Ecuadorian Squirrel Monkey

The objective of this study was to describe and compare the head morphometry of normal and pathological sperm from Saimiri macrodon. In the morphological analysis, 39% of the sperm had normal morphology, and 61% had major or minor defects, with pathology in the tails being the most frequent with 47% (38% curled tail, 7% folded tail and 2% strongly folded tail). Among the evaluated head morphometry parameters, area (A), width (L) and ellipticity (E) showed statistical difference (p>0.05) between normal and pathological sperm. The average head area and width was lower in normal sperm (p=0,01 e p=0,04, respectively), and the mean ellipticity was higher (p=0,038), when compared to pathological sperm. This definition of the sperm morphometric parameters of S. macrodon is important for the samples selection destined to reproduction biotechnologies and for the clarification of taxonomic and evolutionary issues in the genus Saimiri.

Gincana anatômica - metodologia ativa no ensino-aprendizagem da Medicina Veterinária: relato de caso / Anatomy competition - active methodology in teaching-learning of Veterinary Medicine: case report

O presente trabalho descreve uma metodologia ativa para auxiliar o ensino-aprendizado na formação de profissionais mais capacitados e contribuir como modelo de estudo para alunos da disciplina de Anatomia Veterinária. A gincana foi realizada com a participação de alunos (n = 48) do primeiro semestre da Faculdade de Medicina Veterinária da Universidade Federal do Pará - Castanhal, no ano de 2018. A turma foi dividida nos grupos A e B, com 24 discentes em cada. O docente (mediador) informou as regras da atividade. Os representantes do grupo A foram alocados em cadeiras individuais de nº 1 a 24 em um lado da sala, o mesmo ocorreu para o grupo B, no lado oposto. A atividade foi iniciada pela dupla da cadeira nº 1 por grupo e finalizada pela dupla da cadeira nº 24. Cada dupla foi chamada pelo mediador da atividade a sentar nos dois bancos no centro da sala, e então foi realizado o ‘par ou ímpar com cada dupla para o vencedor escolher um balão pregado na parede da sala, estourar e direcionar o papel que estava no seu interior com as instruções da atividade a ser proposta pelo mediador. As atividades consistiam em 1) responder as perguntas, 2) realizar mímica e 3) participar da “caixa misteriosa”. As pontuações foram acerto (+) ou erro (-), conforme critérios preestabelecidos no papel no interior do balão. A utilização de MA despertou a curiosidade dos alunos, exigindo que eles adquirissem mais conhecimento para poder participar da atividade e apesar de haver restrições na análise de sua efetividade por se tratar apenas de aspectos extraídos da fala dos estudantes, a dinâmica educacional auxiliou no desenvolvimento de competências técnicas e humanísticas. A experiência realizada destaca a importância da difusão de técnicas ativas de ensino, especialmente, em instituições de ensino superior.(AU)

The aim of this study was the description of an active learning that can assist the teaching-learning process (TLP) in the formation of more qualified professionals, and to contribute as a study model for students of Veterinary Anatomy. A total of 48 first year students from the Faculty of Veterinary Medicine (Universidade Federal do Pará/Castanhal) participated in the game. The class was divided into groups A and B, with 24 students in each of them. The teacher (mediator) informed the rules of the activity. The representatives of group A were allocated individual chairs from number 1 to 24 on one side of the room, and the same occurred for group B on the opposite side. Each pair was called by the mediator to sit on two benches in the center of the room, and then a game of “odd or even” was played with each pair so that the winner could choose a balloon stuck on the wall of the room, pop it, and send the paper with the instructions of the activity to the mediator. The activities consisted of 1) answering the questions, 2) mimic, and 3) participate in the “mystery box”. The scores were hit (+) or error (-) according to pre-established criteria. The use of TLP aroused the students curiosity, demanding that they acquire more knowledge in order to participate in the activity. And although there are restrictions in the analysis of its effectiveness because it deals only with aspects extracted from the students speech, the educational dynamics helped in the development of technical and humanistic skills. Thus, the practice applied showed the importance of active learning techniques dissemination, mainly in higher education institutions.(AU)

Análise morfométrica da cabeça espermática em Saimiri cassiquiarensis / Morphometric analysis of the sperm head in Saimiri cassiquiarensis

The objective was to evaluate the sperm morphometry between normal and pathological cells in Saimiri cassiquiarensis aiming at the future use of data in CASA (Computer Assisted Sperm Analysis). Semen was collected from a male (S. cassiquiarensis) by electroejaculation. After collection, a smear in the proportion of 1:1 (semen and eosin-nigrosin stain) was performed, and 100 sperm were measured and morphologically classified as normal and pathological defects (major and minor). Of the total sperm analyzed, 48% were classified as normal and 52% pathological. Of the pathologies, the most frequent was a folded tail (40%), followed by a strongly folded tail (5%), curled tail (2%) and isolated head (5%). The morphometric data showed no statistical difference (p<0.05) between normal and pathological defects. This is the first description for the sperm morphometry in Saimiri cassiquiarensis, therefore, from this database, future assessments at CASA can be conducted for this species.

Análise morfométrica da cabeça espermática em Saimiri cassiquiarensis / Morphometric analysis of the sperm head in Saimiri cassiquiarensis

The objective was to evaluate the sperm morphometry between normal and pathological cells in Saimiri cassiquiarensis aiming at the future use of data in CASA (Computer Assisted Sperm Analysis). Semen was collected from a male (S. cassiquiarensis) by electroejaculation. After collection, a smear in the proportion of 1:1 (semen and eosin-nigrosin stain) was performed, and 100 sperm were measured and morphologically classified as normal and pathological defects (major and minor). Of the total sperm analyzed, 48% were classified as normal and 52% pathological. Of the pathologies, the most frequent was a folded tail (40%), followed by a strongly folded tail (5%), curled tail (2%) and isolated head (5%). The morphometric data showed no statistical difference (p<0.05) between normal and pathological defects. This is the first description for the sperm morphometry in Saimiri cassiquiarensis, therefore, from this database, future assessments at CASA can be conducted for this species.(AU)