Adriana Gradela

Características do sêmen a fresco e descongelado de garanhões da raça Nordestina

Este estudo descreveu as caracteristicas seminais, da membrana plasmatica e do acrossoma de espermatozoide congelado/descongelado de 19 ejaculados de garanhoes da raca Nordestina. Os aspectos analisados incluiram os parâmetros fisicos do semen fresco; a motilidade e a longevidade do semen diluido e descongelado; a morfologia espermatica, integridade funcional e estrutural da membrana plasmatica do espermatozoide e a habilidade de ligacao do espermatozoide a membrana perivitelina da gema do ovo de galinha do semen descongelado. As variaveis foram avaliadas pela ANOVA com post hoc teste de Student Newman-Keuls (P<0,05). A MT e a MP foram maiores (P<0,05) no semen diluido do que no descongelado. A percentagem media de defeitos maiores, menores e totais foi muito inferior ao limite recomendado pelo CBRA. A porcentagem de reativos ao HOST foi de 14,21±1,12% e a porcentagem media de membranas integras detectadas pelo teste supravital de 62,22±9,06% e pela sonda SYBR-14 de 81,47±26,90. O numero medio de espermatozoides ligados a MPV apos a descongelacao do semen foi de 230,39±57,09. A MT e MP no tempo 0 min do TTR foi superior (P<0,05) em relacao a 150 min, nao diferindo nos tempos 10 min e 30 min. Os resultados demonstram que a utilizacao dos testes laboratoriais adicionais ajudam no processo de avaliacao das amostras, possibilitando a obtencao de informacoes mais confiaveis e precisas. Embora a criopreservacao tenha provocado queda na motilidade seminal, o uso de diluidor contendo amidas minimizou os danos osmoticos nas celulas espermaticas e manteve a integridade morfologica, funcional e estrutural da membrana plasmatica do espermatozoide. Estes resultados sao um referencial em estudos futuros uma vez que, inexistem dados comparativos nesta raca.

Descrição morfológica e morfométrica da glândula vesicular de cobaias durante o desenvolvimento pós-natal

Vesicular glands are essential for reproduction since their secretions affect sperm function. Guinea pigs (Cavia porcellus) are an excellent experimental model for studying vesicular glands, but no morphologic and morphometric data during its development are available. In the present study, the morphology (projections of the folds (PF) and epithelial tissue high (EH) of the mucosa) and the morphometry (mass (GM), volume (GV), length (GC), width of the portions cranial (CRW), medium (MW) and caudal (CAW)) of the vesicular glands were determined at 1, 3, 5, 8, and 11-weeks of age in male guinea pigs (n = 5/age group). In addition, body mass (BM), body length (BL) and height (BH) and organo-somatic index (OSI) were also determined and the simple correlation coefficient (r) was established between the variables. The glands were restricted to the pelvic cavity, and had its interior filled with a semi-solid mass and, after S8, they occupied also the abdominal cavity and the contents were increased significantly. The mucous membrane presented variable folding and simple columnar epithelium. BM, BL and BH increased continuously with age. GM, GV, GC and CAW did not change from 1 to 5-weeks of age, but increased at 8-weeks of age; GM, GV and LCA also increased at 11-weeks of age. OSI and PF increased at 8 and 11-weeks of age and EH at 5, 8 and 11-weeks of age. There was significant (r) between age, body and glandular parameters; OSI and GM at 8 and 11-weeks of age; age and PF, age and EH and between PF and EH. In conclusion, the guinea pigs vesicular glands followed morphology observed in rats and hamsters, but differed in some aspects from others histricomorfs, can be used as experimental model and its morphological and morphometric development can be divided into three phases: 1 to 5-weeks of age, when they are discrete; 6 to 8-weeks of age when they are generally sharp and >8-weeks of age, when there is an intense increase of the secretory capacity.

Análise morfológica e funcional do processo espermatogênico em cobaios (Cavia porcellus) da pré-puberdade até a pós-puberdade

This study describes the morphological and functional analysis of spermatogenesis in guinea pigs (Cavia porcellus) with five (W5), six (W6), nine (W9) and eleven (W11) weeks of age (n=5/group). The aspects analyzed include counts of cell populations present in stage 1 of seminiferous epithelium cycle (SEC), efficiency of spermatogonial mitosis (EMi), meiotic production (EMe), overall yield of spermatogenesis (EOS), Sertoli cell index (SCI) and carrying capacity of Sertoli cells (CCSC). The results showed that the average number of spermatogonia type A, primary spermatocytes in pre-leptoteno/leptoteno, primary spermatocytes in pachytene, total spermatogenic cells and Sertoli cells showed numerical variations according to age; however they were statistically not detected, while round spermatids increased significantly at puberty and then stabilized. The spermatogenic production of 5 to 11-week-old guinea pigs did not reach the stabilization point, and the RMi, RME, EOS, SCI and CCSC showed significant number variation as a function of age. The results demonstrate that Cavia porcellus in post-pubertal stage 2 are an advantageous experimental model to address studies on the processes of homologous recognition, alignment, and synapsis during meiotic prophase; intrinsic yield of spermatogenesis in guinea pigs is similar to Wistar rats, paca and agouti (Dasyprocta sp.) and lower than in cavies, whereas the functional efficiency of Sertoli cells is higher than in agouti and Wistar rats, and lower than in pacas, spiny rat and collared peccaries. We conclude that in guinea pigs the spermatogenesis is fully established at 6 weeks of age, indicating the pubertal stage of sexual development, and until week 11 they do not reach the maximum daily sperm production and therefore sexual maturity.

Biometria corporal e parâmetros hematológicos de Trachemys scripta elegans e Trachemys dorbignyi (Testudines: Emydidae) criadas em cativeiro em Petrolina, Pernambuco

This study aimed to evaluate the body biometry and hematological profile of Trachemys scripta elegans (N=28) and Trachemys dorbignyi (N=22) reared in captivity in the Brazilian submedium northeastern semi-arid region in the Valley of the Sao Francisco river. It aimed to establish basic health blood values and generate useful data on the comparative physiology of Testudines. After 120-day adaptation and 24-hour fasting, 2.5mL of blood were collected from the dorsal occipital sinus and deposited into a tube with sodium heparin for evaluation, following, of hematological levels. The red blood cell count (RBC) and GLC was conducted in a Neubauer chamber, the hemoglobin level (HGB) was supplied by the cyanmethemoglobin method and the hematocrit (HCT) was obtained by the microhematocrit technique. Based on the RBC, the hematimetric were mathematically established. Body biometry were also evaluated: a) body mass (BM, g); b) maximum dimensions of the carapace [length (MLC, cm) and width (MWC, cm)]; c) maximum dimensions of plastron [length (MLP, cm) and width (MWP, cm)]; d) total length of tail (TLT, cm); e) linear length from the base of the tail to the cloacal orifice (LPrC, cm); f) linear length from the cloacal orifice to the extremity of the tail (LPoC, cm). T. scripta elegans showed higher values (P 0.05) among species. The results show that most of the variation found between T. scripta elegans and T. dorbignyi is explained by the biometric variables and that some hematologic correlations characterize interspecies differences. It was conclude that the results shed light on benchmarks for these species kept in captivity in the northeastern semi-arid region and serve as a model for intra and interspecies comparative physiology.

Morphological development of the testicles and spermatogenesis in guinea pigs (Cavia porcellus Linnaeus, 1758)

Introduction: Understanding the dynamics of spermatogenesis is crucial to clinical andrology and to understanding the processes which define the ability to produce sperm. However, the entire process cannot be modeled in vitro and guinea pig may be an alternative as animal model for studying human reproduction. Objective: In order to establish morphological patterns of the testicular development and spermatogenesis in guinea pigs, we examined testis to assess changes in the testis architecture, transition time from spermatocytes to elongated spermatids and stablishment of puberty. Materials and methods: We used macroscopic analysis, microstructural analysis and absolute measures of seminiferous tubules by light microscopy in fifty-five guinea pigs from one to eleven weeks of age. Results: Differences in relation to mass, length and width of the testes appeared at week 3 and were intensified in week 6 with the puberty. At week 2 the first spermatocytes at preleptotene/leptotene appeared, indicating the onset of meiosis. At week 6 the seminiferous tubules formed lumen, differentiated Sertoli cells and all kinds of germ cells; spermatozoa released into the lumen and the largest expansion of tubular diameter and height of the seminiferous epithelium occurred. Transition time from spermatocytes to elongated spermatids was estimated in 21 days. Conclusion: We conclude that the testicular development and puberty are faster than in other mammal and rodent species, demonstrating the suitability of the guinea pig testes as a model for studies of the testicular development and spermatogenesis.