Toward an integrative and predictive sperm quality analysis in Bos taurus

There is a need to develop more integrative sperm quality analysis methods, enabling researchers to evaluate different parameters simultaneously cell by cell. In this work, we present a new multi-parametric fluorescent test able to discriminate different sperm subpopulations based on their labeling pattern and motility characteristics. Cryopreserved semen samples from 20 Holstein bulls were used in the study. Analyses of sperm motility using computer-assisted sperm analysis (CASA-mot), membrane integrity by acridine orange-propidium iodide combination and multi-parametric by the ISAS®3Fun kit, were performed. The new method allows a clear discrimination of sperm subpopulations based on membrane and acrosomal integrity, motility and morphology. It was also possible to observe live spermatozoa showing signs of capacitation such as hyperactivated motility and changes in acrosomal structure. Sperm subpopulation with intact plasma membrane and acrosome showed a higher proportion of motile sperm than those with damaged acrosome or increased fluorescence intensity. Spermatozoa with intact plasmalemma and damaged acrosome were static or exhibit weak movement. Significant correlations among the different sperm quality parameters evaluated were also described. We concluded that the ISAS®3Fun is an integrated method that represents an advance in sperm quality analysis with the potential to improve fertility predictions

Docencia asistida por ordenador en infografía

La docencia asistida por ordenador se aplica a diferentes y muy diversas áreas o materias. En nuestro caso, hemos elegido los gráficos por ordenador por ser un tema donde inherentemente aparecen conceptos gráficos e interactivos. El objetivo de este trabajo es desarrollar un entorno donde el alumno pueda acceder a la gran mayoría de conceptos básicos relacionados con la Infografía. Está orientado a un primer curso de Informática Gráfica de una Ingeniería Técnica. Como objetivo complementario, el proyecto pretende, además de suministrar la información fundamental para el buen desarrollo de la asignatura, orientar al estudiante y ayudar al docente en dicha materia para una posterior y mayor formación. Por ello, se incluyen direcciones de interés en Internet, bibliografía complementaria y específica, asociaciones relacionadas, software shareware, congresos y conferencias. La utilización del lenguaje Java1 hace posible una interactividad completa. Finalmente, otro objetivo fundamental es la ampliación de las librerías de Java para incluir nuevos métodos gráficos tridimensionales.Eje: Ateneo de profesores universitarios de computaciión. Informática educativaRed de Universidades con Carreras en Informática (RedUNCI

Ability of the isas3fun method to detect sperm acrosome integrity and its potential to discriminate between high and low field fertility bulls

The objective of the present study was to investigate whether fertility differences in bulls are reflected in variations of sperm quality when analysing only one ejaculate per male. Two experiments were performed. In the first experiment, frozen semen samples from 20 adult bulls were tested; 10 bulls had high field fertility and 10 bulls had low field fertility. Analyses of sperm motility, membrane integrity, and membrane–acrosome integrity with the ISAS3Fun method were performed. Sperm morphometry of the fluorescence sperm subpopulations obtained with the ISAS3Fun method was also analysed. Significant differences between high-and low-fertility groups were only found with the ISAS3Fun technique, specifically in sperm acrosome integrity, the proportion of spermatozoa with an intact acrosome and damaged membrane, and in sperm head width of spermatozoa with intact structures. Discriminant analyses allowed us to correctly classify 90% of sperm samples in their fertility group using sperm quality parameters. Given that only the results obtained with the ISAS3Fun technique were related to bull fertility, we performed a second experiment aimed to validate the efficacy of this technique to detect the acrosomal integrity of bull spermatozoa, comparing them with the conventional FITC-PNA/propidium iodide (PNA/PI) combination under capacitating conditions. The results indicated that the ISAS3Fun combination provided an accurate assessment of both viability and acrosomal integrity for ejaculated spermatozoa, while the PNA/PI combination underestimated the extension of acrosomal damage due to false negatives. It was concluded that the simultaneous assessment of sperm plasma membranes and acrosome integrity with the ISAS3Fun method is precise and seems to have a greater potential to discriminate between high-and low-fertility bulls than more conventional in vitro sperm quality tests. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

Predictive capacity of boar sperm morphometry and morphometric sub-populations on reproductive success after artificial insemination

The aim of the study was to compare the morphometric features of sperm head size and shape from the Pietrain line and the Duroc × Pietrain boar crossbred terminal lines, and to evaluate their relationship with reproductive success after artificial insemination of sows produced from crossbreeding the York, Landrace and Pietrain breeds. Semen samples were collected from 11 sexually mature boars. Only ejaculates with greater than 70% motility rate and <15% of abnormal sperm were used for artificial inseminations (AI) and included in the study. Samples were analyzed using an ISAS®v1 computer-assisted sperm analysis system for eight morphometric parameters of head shape and size (CASA-Morph). Sub-populations of morphometric ejaculates were characterized using multivariate procedures, such as principal component (PC) analysis and clustering methods (k-means model). Four different ejaculate sub-populations were identified from two PCs that involved the head shape and size of the spermatozoa. The discriminant ability of the different morphometric sperm variables to predict sow litter size was analyzed using a receiver operating characteristics (ROC) curve analysis. Sperm head length, ellipticity, elongation, and regularity showed significant predictive capacity on litter size (0.59, 0.59, 0.60, and 0.56 area under curve (AUC), respectively). The morphometric sperm sub-populations were not related to sow litter size

Docencia asistida por ordenador en infografía

La docencia asistida por ordenador se aplica a diferentes y muy diversas áreas o materias. En nuestro caso, hemos elegido los gráficos por ordenador por ser un tema donde inherentemente aparecen conceptos gráficos e interactivos. El objetivo de este trabajo es desarrollar un entorno donde el alumno pueda acceder a la gran mayoría de conceptos básicos relacionados con la Infografía. Está orientado a un primer curso de Informática Gráfica de una Ingeniería Técnica. Como objetivo complementario, el proyecto pretende, además de suministrar la información fundamental para el buen desarrollo de la asignatura, orientar al estudiante y ayudar al docente en dicha materia para una posterior y mayor formación. Por ello, se incluyen direcciones de interés en Internet, bibliografía complementaria y específica, asociaciones relacionadas, software shareware, congresos y conferencias. La utilización del lenguaje Java1 hace posible una interactividad completa. Finalmente, otro objetivo fundamental es la ampliación de las librerías de Java para incluir nuevos métodos gráficos tridimensionales.Eje: Ateneo de profesores universitarios de computaciión. Informática educativaRed de Universidades con Carreras en Informática (RedUNCI

Effect of sperm concentration and storage temperature on goat spermatozoa during liquid storage

The use of cooled semen is relatively common in goats. There are a number of advantages of cooled semen doses, including easier handling of artificial insemination (AI) doses, transport, more AI doses per ejaculate, and higher fertility rates in comparison with frozen AI doses. However, cooled semen has a short shelf life. The objective of this study was to examine the effect of temperature and sperm concentration on the in vitro sperm quality during liquid storage for 48 h, including sperm motility and kinetics, response to oxidation, mitochondrial membrane potential (MMP) and DNA fragmentation in goats. Three experiments were performed. In the first, the effects of liquid preservation of semen at different temperatures (5 °C or 17 °C), durations (0, 24 and 48 h) and sperm concentrations (250 × 106 sperm/mL (1:2 dilution rate), 166.7 × 106 sperm/mL (1:3 dilution rate) or 50 × 106 sperm/mL (1:10 dilution rate)) on sperm motility and kinetics were studied. In the second experiment, the effect of temperature, sperm washing and concentration on sperm motility and DNA fragmentation was studied. Finally, the effect of sperm concentration and duration of storage at 5 °C on sperm motility, response to oxidative stress and MMP was examined. We found that refrigerated liquid storage of goat sperm impaired sperm quality, such as motility, MMP and response to oxidation, as storage time increased; however, sperm DNA fragmentation index was not significantly affected. Liquid storage at 5 °C preserved higher total motility than at 17 °C. Moreover, we observed that the reduction of sperm concentration below 500 × 106 sperm/mL did not seem to improve the quality of spermatozoa conserved in milk-based extender in the conditions teste

Expanding the limits of computer-assisted sperm analysis through the development of open software

Computer assisted sperm analysis (CASA) systems can reduce errors occurring in manual analysis. However, commercial CASA systems are frequently not applicable at the forefront of challenging research endeavors. The development of open source software may offer important solutions for researchers working in related areas. Here, we present an example of this, with the development of three new modules for the OpenCASA software (hosted at Github). The first is theChemotactic Sperm Accumulation Module, a powerful tool for studying sperm chemotactic behavior, analyzing the sperm accumulation in the direct vicinity of the stimuli. This module was validated by comparing fish sperm accumulation, with or without the influence of an attractant. The analysis clearly indicated cell accumulation in the treatment group, while the distribution of sperm was random in the control group. The second is the Sperm Functionality Module, based on the ability to recognize five sperm subpopulations according to their fluorescence patterns associated with the plasma membrane and acrosomal status. The last module is the Sperm Concentration Module, which expands the utilities of OpenCASA. These last two modules were validated, using bull sperm, by comparing them with visual counting by an observer. A high level of correlation was achieved in almost all the data, and a good agreement between both methods was obtained. With these newly developed modules, OpenCASA is consolidated as a powerful free and open-source tool that allowsdifferent aspects of sperm quality to be evaluated, with many potential applications for researchers

Short communication. Evaluation of a commercial kit based on acridine orange/propidium iodide to assess the plasma membrane integrity of ram sperm

This study was designed to develop a semiautomatic computer assisted methodology to evaluate the membrane integrity of ram spermatozoa using a commercial kit based on acridine orange/propidium iodide (AO/PI) labelling and ImageJ software. The study was divided into two experiments. In the first trial, the new computer-assisted method was validated by mixing fresh semen samples with different volumes of freeze killed spermatozoa to determine proportions of damaged spermatozoa in the final samples. The proportion of damaged spermatozoa in each sample determined by the automated procedure where highly correlated (R2=0.97, p&lt;0.001) with the predicted theoretical values. In the second trial, the new method was compared with a previously validated method of membrane integrity assessment based on phase-contrast/propidium iodide (PH/PI) methodology. Measurements by AO/PI were, on average, 4.0% larger than measurements by PH/PI (SD=7.02%) and 1.79% smaller than measurements of sperm motility determined by CASA (SD=4.83). The AO/PI method was also more repeatable than the PH/PI. The double staining methodology coupled with the routine for image analysis allowing automatic determination of sperm membrane integrity means a reduction in processing time of 75% compared to the previously developed method using a single fluorochrome (3 vs 12 min on average if the incubation period was included). This facilitates its use when a large number of samples are analysed. Our results validate the new computer assisted method for assessing sperm membrane integrity in sheep. The new method developed, in addition to being a free tool, allows quick automatic determination of sperm viability, which facilitates its use in routine semen analysis