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RESUMO.-O objetivo deste estudo foi monitorar o ciclo estral em cutias (Dasyprocta leporina) criadas em cativeiro no semiárido brasileiro. Durante 70 dias, cinco cutias foram diariamente submetidas a citologia esfoliativa vaginal, e o monitoramento ultrassonográfico ovariano foi realizado a cada três dias. Um total de 8 ciclos estrais foi completamente monitorado, com duração de 28,2±0,7 dias, variando de 24 a 31 dias. Pela citologia esfoliativa vaginal, houve uma predominância de células superficiais nas fases de proestro e estro (P<0,05), seguida da predominância de células intermediárias no metaestro (P<0,05) e de células parabasais no diestro (P<0,05). Por ultrassonografia, não houve diferenças na morfologia ovariana durante as diferentes fases do ciclo estral (P>0,05). Os folículos foram identificados durante as fases estrogênicas (proestro e estro), com diâ-metro médio de 1±0,5mm. Em apenas 12,5% das fases luteais, corpos lúteos medindo 1,4±0,9mm foram identificados. Conclui-se que a associação da citologia vaginal e da ultrassonografia ovariana constitui uma alternativa viável para o monitoramento de ciclos estrais e identificação das fases estrogênicas em cutias da espécie Dasyprocta leporina. TERMOS DE INDEXAÇÃO:Dasyprocta leporina, roedores, colpocitologia, ecografia ovariana. INTRODUÇÃOAs cutias (Dasyprocta sp.) são roedores utilizadas frequentemente como fonte de alimento e extração de sua pele, couro e pelos por populações humanas (Lopes et al. 2004 The objective of the study was to monitor the estrous cycle in agoutis (Dasyprocta leporina) bred in captivity in Brazilian semiarid. During 70 days, five agoutis were daily subjected to vaginal exfoliative cytology, and the ovarian ultrasound monitoring was conducted every three days. A total of 8 estrous cycles were completely monitored, lasting 28.2±0.7 days, ranging from 24 to 31 days. By vaginal exfoliative cytology, there was predominance of superficial cells at proestrus and estrus phases (P<0.05), followed by the predominance of intermediate cells in the metestrus (P<0.05) and parabasal cells in diestrus (P<0.05). By ultrasound, there were no differences in ovarian morphology during the different phases of the estrous cycle (P>0.05). Follicles during the estrogenic phases (proestrus and estrus) were identified, with an average diameter of 1±0.5mm. In only 12.5% of luteal phases, corpora lutea measuring 1.4±0.9mm were identified. We conclude that the association of vaginal cytology and ovarian ultrasonography is a useful alternative for monitoring the estrous cycle and identifying the estrogenic phases in Dasyprocta leporina.INDEX TERMS: Dasyprocta leporina, rodents, colpocytology, ovarian echography.

The objective was to determine the effectiveness of a powdered coconut water-based extender (ACP-116c), plus various concentrations of egg-yolk and glycerol, as an alternative for cryopreservation of collared peccary semen. Twelve ejaculates were obtained from captive adult males by electroejaculation, and evaluated for sperm motility, kinetic rating, viability, morphology, and functional membrane integrity. The ejaculates were apportioned into aliquots that were diluted in Tris plus 10% egg yolk and 3% glycerol, or in ACP-116c plus 10 or 20% egg yolk and 1.5 or 3% glycerol. Samples were frozen in liquid nitrogen and, after 1 mo, thawed at 37 °C for 1 min. After thawing, samples were evaluated as reported for fresh semen, and also for sperm membrane integrity (fluorescent probes) and kinematic parameters (computerized analysis). Results were presented as means ± SEM. Freezing and thawing decreased sperm characteristics relative to fresh semen. Overall, ACP-116c plus 20% egg yolk and 3% glycerol provided better (P < 0.05) sperm motility and kinetic rating (48 ± 6.1% and 2.8 ± 0.2, respectively) after thawing than Tris extender (30.4 ± 5.7% and 2.4 ± 0.2). However, there were no differences (P > 0.05) among treatments with regard to the other sperm characteristics. Based on computerized motion analysis, total (26.5 ± 5.9%) and progressive (8.1 ± 2.2%) motility were best preserved (P < 0.05) with the above-mentioned treatment. In conclusion, a coconut water-based extender, ACP-116c, plus 20% egg yolk and 3% glycerol, was effective for cryopreservation of semen from collared peccaries.

The present study is aimed at evaluating the effect of centrifugation for seminal plasma removal and the supplementation of fructose or glucose to the Tris-based extender on the kinematic patterns of the motility parameters of frozen-thawed semen obtained from captive collared peccaries (Tayassu tajacu). Semen samples (n = 14) were collected from 10 sexually mature male collared peccaries by electroejaculation. These samples were further evaluated for parameters such as motility, vigor, sperm viability, membrane integrity, and sperm morphology. The samples were divided into four aliquots, and only two of these aliquots were centrifuged. The semen aliquots (centrifuged and raw semen samples) were diluted in Tris-based extenders supplemented with fructose or glucose. Egg yolk (20%) and glycerol (3%) were added to all the samples which were cryopreserved in liquid nitrogen and thawed at 37 °C/1 min. The frozen-thawed semen was evaluated for the same parameters described for the fresh semen. On the other hand, the kinematic motility patterns were evaluated by a computer-aided system. After thawing, it was observed that the values for the total sperm motility were around 30% for all the samples. A negative effect of centrifugation was verified for parameters such as sperm morphology, linearity, straightness, and beat cross frequency (P < 0.05). However, no differences between fructose and glucose were verified for any semen end point (P > 0.05). In conclusion, it is not recommended to centrifuge the ejaculates from collared peccaries prior to conducting the cryopreservative procedures using a Tris-based extender supplemented with fructose or glucose.

Cryopreservation of somatic tissue can be applied in biodiversity conservation, especially for wild species as collared peccary. We aimed to evaluate the effect of vitrification techniques of ear tissue of collared peccary [direct vitrification in cryovials (DVC) or solid-surface vitrification (SSV)] on the layers of epidermis and dermis by conventional histology and cell ability during the in vitro culture. Thus, both the vitrification methods were able to maintain normal patterns of the epidermis as the cornea and granular layers, furthermore the intercellular space and dermal-epidermal junction of the spinous layer when compared to fresh control. Nevertheless, DVC and SSV percentage of normality decreased in the morphological integrity of cytoplasm (37.5 and 25.0%) of spinous layer, respectively, as compared to the fresh fragments (100%, p < 0.05). Moreover, other differences between the fresh control (100%) and DVC tissues were verified in the intra-epidermal cleavage of the spinous (37.5%) and basal (37.5%) layers. In general, DVC and SSV techniques were efficient for the recovery of the somatic cells according to most of the evaluated parameters for the in vitro culture (p > 0.05). In addition, only at time of 72 h (D3), in the growth curve, DVC fragments showed a reduced cell concentration than fresh control. In conclusion, SSV was found to be a more efficient method for vitrifying collared peccary skin tissue when compared to DVC. These results are relevant for the tissue cryopreservation from collared peccary and could also be useful for mammals with phylogenetic relationships.

The aim of the present study was to characterise the ovarian preantral follicle (PF) population and to establish a solid surface vitrification (SSV) process using dimethyl sulfoxide (DMSO) as a cryoprotectant for preservation of ovarian tissue from yellow-toothed cavies (Galea spixii). Ovaries were fixed for PF population analysis or were subjected to the SSV process. The mean (± s.e.m.) PF population per ovarian pair was estimated to be 416.0±342.8. There were 140.0±56.0 (63.4%) and 125.0±58.0 (64.0%) primary follicles on the right and left ovaries, respectively. The proportion of this follicle category was significantly greater than that of other follicle categories (P<0.05). The diameter of follicles (123.7±18.3µm), oocytes (50.1±5.0µm) and nuclei (14.27±2.01µm) was larger for secondary ones when compared with other PFs categories. Most PFs were morphologically normal (94.6%), with light microscopy identifying only a few atretic follicles (5.4%). After SSV, there was a reduction in the proportion of morphologically normal PFs compared with the non-vitrified group (69.5% vs 91.2%, respectively). Transmission electron microscopy revealed preservation of oocytes and granulosa cell membranes and the morphological aspect of follicles; the primary change observed in some vitrified PFs was the presence of vacuoles in the oocytes and granulosa cells cytoplasm and turgid mitochondria. In conclusion, the present study provides an estimative and characterization for the PF population in ovaries of G. spixii. Moreover, we report its PFs cryopreservation using an SSV process.

The aim of this research was to characterize the preantral ovarian follicular population in collared peccaries (Tayassu tajacu) using light and electron microscopy. Ovaries from six mature females were collected and further fixed for histological and ultrastructural analysis. A total of 33273.45 AE 5789.99 preantral follicles (PFs) were estimated for the population in each ovary. Most preantral follicles were primordial (91.56%), followed by primary (6.29%) and secondary (2.15%) ones. Most PFs were morphologically normal (94.4%), and only a few were atretic (5.6%). At histology assessment, amounts of lipid droplets were observed into the oocyte cytoplasm, which was confirmed through ultrastructural analysis. This work characterizes for the first time the ovarian population of preantral follicles, total and per category, in collared peccaries (Tayassu tajacu). The general follicles featured at primordial, primary and secondary categories are very similar to those described for other species.