Idade masculina: Qualidade do sêmen e fertilidade: Idade masculina X qualidade seminal

The man's age seems to affect reproductive function but to a lower degree compared with the woman's age. In fact, the effect of paternal age on semen quality has been discussed, but the results are contradictory. Considering the differences in the results of studies, this review aimed to analyze the literature regarding the effect of paternal age on semen parameters (volume, concentration, motility and morphology) in sperm DnA damage in assisted reproduction results and genetic diseases.

Congelação de espermatozoides epididimários de gatos utilizando o diluidor Botu-crio® após refrigeração por 24 h em contêiner de transporte de sêmen Botu-tainer®

The possibilities of using the sperm collected from the epididymis have been widely used because the fertilizing capacity sperm preservation and the possibility of using it for wild cats. But in the process of cryopreservation, some studies show a decrease in the quality of the sperm when left under cooling before frozen for some time. This study aimed to assess the quality of the epididymal sperm obtained from domestic cats after cryopreservation using a diluent based on egg yolk and glycerol (Botu-crio®), comparing the morphofunctional characteristics after cooling for 24 hours in a container of semen transport (Botu-tainer®). We use eight cats submitted to elective orchiectomy, aging from eight months, without racial determination, and good nutritional status. These sperm characteristics were: motility, vigor, concentration, membrane integrity and morphology. It has been found, after statistical analysis, that the container of semen was able to maintain sperm viability, even for 24h. We also observed a significant decrease on all parameters after frozen, consequential, probably to thermal stress that occurs in processing. However, the percentage of membrane integrity after thawing shows good employability of the Botu-crio®, which viability is possible to perform in vitro fertilization, requiring higher ratings.

Possible mechanism by which zinc protects the testicular function of rats exposed to cigarette smoke

Background: The aim of this study was to evaluate the changes in testicular function of rats due to cigarette smoke exposure and the possible mechanism by which zinc protects against these alterations. Methods: MaleWistar rats (60 days old) were randomly divided into 3 groups: control (G1, n = 10); exposed to cigarette smoke (G2, n = 10; 20 cigarettes/day/9 weeks) and exposed to cigarette smoke and supplemented with zinc (G3, n = 8; 20 cigarettes/day/9 weeks; 20 mg/kg zinc chloride daily for 9 weeks, by gavage). After the treatment period, the animals were euthanized, and materials were collected for analyses. Results: G2 rats showed a reduction in body mass; impaired sperm concentration, motility, morphology and vitality; and increased malonaldehyde and thiol group levels and superoxide dismutase activity as compared to G1. Zinc prevented the reduction of sperm concentration and the excessive increase of lipid peroxidation and induced an increase in plasma testosterone levels, wet weight of testis and thiol group concentration. Conclusions: Exposure to cigarette smoke led to harmful effects on testicular function at least partially due to the exacerbation of oxidative stress. Supplementary zinc had an important modulator/protector effect on certain parameters. The mechanism of zinc protection can be through an increase of SH concentration. Thus, zinc supplementation may be a promising addition to conventional treatments for male infertility related to smoking. Copyright © 2012 by Institute of Pharmacology Polish Academy of Sciences.

Identification of sperm head subpopulations with defined pleiomorphic characteristics in ejaculates of captive Goeldi's monkeys (Callimico goeldii)

The aim of this study was to evaluate the incidence of pleiomorphisms and its influence on the distribution of sperm morphometric subpopulations in ejaculates from the vulnerable Goeldi's monkey (Callimico goeldii) by using a combination of computerized analysis system and Principal Component Analysis (PCA) methods Each sperm head was measured for four primary spermatozoal head dimensional parameters (area [A (μm2)], perimeter [P (μm)], length [L (μm)] and width [W (μm)]) and three head shape derived parameters (ellipticity [(L/W)], elongation [(L-W)/(L+W)] and rugosity [(4πA/P2)]) Six separate subpopulations (SPs) were identified: SP1, constituted by very large, narrow and very elliptical spermatozoa (A=16.85±1.56μm2, W=2.75±0.42μm and ellipticity=2.16±0.24); SP2, characterized by average sized, short, wide and round spermatozoa (A=15.00±1.92μm2, L=5.06±0.49μm, W=3.51±0.31μm and ellipticity=1.44±0.15); SP3, represented by small, wide and slightly round spermatozoa (A=14.95±1.75μm2, W=3.47±0.29μm and ellipticity=1.48±0.14); SP4 included very small, short and very round spermatozoa (A=14.15±2.38μm2, L=4.90±0.57μm and elongation=0.18±0.05); SP5 consisted of average sized and slightly elliptical spermatozoa (A=15.14±1.72μm2 and ellipticity=1.49±0.14); and SP6 included large and round spermatozoa (A=16.30±1.62μm2 and elongation=0.19±0.04) There were differences in the sperm subpopulation distribution (P<0.001) among the five donors analyzed In conclusion, the results of the current study confirmed that the use of computer sperm analysis methods combined with PCA cluster analyses are useful methods to identify, classify, and characterize different sperm head morphometric subpopulations in neotropical primates Broadening our knowledge of C goeldii sperm morphometric abnormalities as well as developing reliable techniques for sperm evaluation may be essential for ex situ conservation of this threatened species © 2012 Elsevier B.V.

High incidence of 'Dag-like' sperm defect in the domestic cat

The occurrence of a high incidence of sperm tail defects in a male domestic cat resembling the known 'Dag-like' defect is reported. Sperm analyses were performed in ejaculated samples collected by an artificial vagina and in testicular and epididymal sperm cells after castration. The following alterations were observed using transmission electron microscope: heavily coiled sperm tails containing several axonemal units enclosed in the same common cell membrane; aberrations in the axonemal main structure; and swollen and unevenly distributed mitochondria in the midpiece. Abnormal modifications in the mitochondrial sheath were also found in sperm cells retrieved from testes and epididymides. Considering these findings, we can conclude that this is the Dag-like defect, described previously in other domestic species and a testicular origin may be involved. © ISFM and AAFP 2012.

Evaluation of semen characteristics of the species Mazama americana in captivity

In recent years the concept of genomic resource banks has grown as a way of maintaining the genetic variability of populations, while the quality of cryopreservation of the gametes determines the effectiveness of such banks. However, the absence of basic knowledge regarding the physiology of species and their semen characteristics hampers the establishment of reproductive biotechnologies. Thus, this paper aimed to determine certain physicochemical (volume, colour, appearance, pH and osmolarity) and microscopic characteristics (mass movement, motility, vigour, concentration, and sperm morphology and morphometry) of semen of the species Mazama americana. To achieve this, five males of the species were used, and three semen samples per buck (electroejaculation) were collected at intervals of 2 weeks. The volume, pH and osmolarity of the ejaculate were 0.39 ± 0.14 mL, 6.90 ± 0.74 and 297.74 ± 19.10 mOsm/kg, respectively, while the values obtained for mass movement, motility, vigour and concentration were 3.33 ± 0.82; 69.6 ± 8.92%; 3.53 ± 0.50, and 244.07 ± 98.65 × 107/mL, respectively. Regarding the colour of the ejaculate, five samples were classified as ivory, two as yellowish, two as whitish and six as white. Regarding appearance, seven samples were considered creamy and eight, milky. Morphology was analysed in a humid chamber under phase contrast microscopy and 73.50 ± 5.57% of cells presented normal morphology, 8.37 ± 3.15% presented major defects and 18.13 ± 6.46% presented minor defects. To determine sperm morphometry, an optical microscope (Leica DM 5000B) and the Leica Qwin image analyser program were used, resulting in 8.09 ± 0.40, 4.65 ± 0.30, 2.81 ± 0.44 and 30.25 ± 3.02 m for length, largest width, smallest width and area, respectively. Copyright © CSIRO 2013.

Seasonal effects on semen and testosterone in zebu and taurine bulls

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

The relationships between scrotal surface temperature, age and sperm quality in stallions

In horses, spermatogenesis normally occurs at an average intratesticular temperature of 35. °C; therefore, mechanisms for testicular thermoregulation are essential. Measuring the scrotal surface temperature by thermography is one of the methodologies used to evaluate the effectiveness of testicular thermoregulation. The objective of this study was to determine the relationship between the control of scrotal surface temperature and sperm quality in horses of different ages. In total, 24 Quarter Horse stallions were divided into three groups: YS (young stallions), AS (adult stallions) and OS (old stallions). Initially, we calculated the testicular volume (TV) and evaluated various aspects of the semen (sperm kinetics, plasma membrane integrity and sperm morphology) for all the animals. We also evaluated rectal temperature (RT), body surface temperature (BST,) and average scrotal surface temperature in the testicular region (SST) before (M0) and after sun exposure (M1). Differences were observed (p<0.05) between the RT and BST before and after sun exposure in all three groups. However, there were no differences (p>0.05) in the SST values at these two time points, thus demonstrating the efficiency of the mechanisms for testicular thermoregulation. The SST was similar (p>0.05) among all three groups. Based on these results, we conclude that fertile stallions of different age groups are able to maintain SST and measuring the heat radiating from the scrotum using a digital infrared thermographer. We can also conclude that measuring the heat radiating from the scrotum using a digital infrared thermographer is a practical and efficient tool for monitoring SST in horses. © 2013 Elsevier B.V.

Genetic parameters for scrotal circumference, breeding soundness examination and sperm defects in young Nellore bulls

A total of 51,161 records of scrotal circumference measurements at 18 mo of age (SCI 8) and 17,648 records of sperm defects and breeding soundness of Nellore bulls (mean age of 22.5 mo), raised under extensive conditions, were analyzed to estimate coefficients of heritability and genetic correlations of morphological semen traits by Bayesian inference. The observed semen traits were classified as minor (MID). major (MAD), and total sperm defects (TD). The animals were classified according to breeding soundness as satisfactory and unsatisfactory potential breeders. The (co)variance components and breeding values were estimated by Gibbs sampling using the GIBBS2F90 program under an animal model that included contemporary group as fixed effect, age of animal as linear covariate, and direct additive genetic effects as random effects. Heritabilities of 0.40 ± 0.02, 0.16 ± 0.02, 0.04 ± 0.01, 0.15 ± 0.01, and 0.10 ± 0.01 were obtained for SCI8, MID, MAD, TD, and breeding soundness, respectively. The SC18 showed a positive and moderate correlation with breeding soundness (0.56 ± 0.04) and a negative and low correlation with MID (-0.23 ± 0.03), MAD (-0.16 ± 0.02), and TD (-0.24 ± 0.02). In conclusion, scrotal circumference showed the best response to selection among the traits studied and was favorably correlated with breeding soundness and sperm morphology in young Nellore bulls. © 2013 American Society of Animal Science. All rights reserved.

Identification of phospholipase C zeta in normospermic and teratospermic domestic cat sperm

In mammalian species, oocyte activation is initiated by oscillations in the intracellular concentration of free calcium ([Ca2+]i), which are also essential to allow embryonic development. To date, evidence supporting the hypothesis that a sperm factor is responsible for initiating oocyte activation has been presented in various mammalian species. Among the possible candidates to be the active sperm factor is the novel sperm-specific phospholipase C ζ (PLCζ), which besides its testis-specific expression is capable of initiating [Ca2+]i oscillations. In this study, we investigated the presence of PLCζ in the sperm of the domestic cat and whether normospermic and teratospermic cats differ in their PLCζ expression. Immunoblotting with anti-PLCζ antibodies confirmed the presence of an immunoreactive band of ~70 kDa in whole sperm lysates of domestic cat as well as in both soluble and insoluble fractions from this sperm. Additional immunoreactive bands, probably C- and N-terminal truncated versions of PLCζ, were also visualized in the soluble sperm fractions. Interestingly, immunoreactivity of PLCζ was detectable in teratospermic sperm, although with slightly less intensity than in normospermic sperm. In conclusion, domestic cat sperm express PLCζ in both cytosolic and high-pH fractions, which is consistent with data in other mammals. Sperm from teratospermic cats also express PLCζ, albeit at reduced concentrations, which may affect the fertility of these males. © 2013 Elsevier Inc..

Biologia reprodutiva e qualidade do sêmen de reprodutores de curimbatá, Prochilodus lineatus, em condições distintas de manejo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Uso de antioxidantes no meio diluente tris para refrigeração e congelação de células espermáticas provenientes de epidídimo de cães submetidos à orquiectomia eletiva

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Função testicular de raos expostos à fumaça do cigarro e possível papel protetor do zinco: análises seminais, morfológicas e moleculares

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Comparação entre diferentes taxas de sêmen na viabilidade espermática em garanhões de alta e baixa congelabilidade

Pós-graduação em Medicina Veterinária - FMVZ

Congelação e efeito do meio sobre as características físico-químicas do sêmen suíno no inverno e verão

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)