Sperm kinematic subpopulations of the American crocodile (Crocodylus acutus)

There has been very limited use of computer assisted semen analysis (CASA) to evaluate reptile sperm. The aim of this study was to examine sperm kinematic variables in American crocodile (Crocodylus acutus) semen samples and to assess whether sperm subpopulations could be characterized. Eight ejaculates (two ejaculates/male) from four sexually mature captive crocodiles were obtained. An ISAS®v1 CASA-Mot system, with an image acquisition rate of 50 Hz, and ISAS®D4C20 counting chambers were used for sperm analyses. The percentages of motile and progressively motile spermatozoa did not differ among animals (P > 0.05) but there was a significant animal effect with regards to kinematic variables (P < 0.05). Principal component (PC) analysis revealed that kinematic variables grouped into three components: PC1, related to velocity; PC2 to progressiveness and PC3 to oscillation. Subpopulation structure analysis identified four groups (P < 0.05), which represented, on average, 9.8%, 32.1%, 26.8%, and 31.3% of the total sperm population. Males differed in the proportion of sperm in each of the kinematic subpopulations. This new approach for the analysis of reptile sperm kinematic subpopulations, reflecting quantifiable parameters generated by CASA system technology, opens up possibilities for future assessments of crocodile sperm and will be useful in the future development of assisted reproduction for these species.

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Liquid Storage of Boar Semen Using Commercial Extenders

Bulletin of University of Agricultural Sciences and Veterinary Medicine Cluj-Napoca Veterinary Medicine ◽

10.15835/buasvmcn-vm:004617 ◽

2018 ◽

Vol 75 (1) ◽

pp. 66

Author(s):

Liviu BOGDAN ◽

Mihai CENARIU ◽

Mihai BORZAN ◽

Simona CIUPE ◽

Lehel SZABO ◽

...

Keyword(s):

Semen Parameters ◽

Computer Assisted ◽

Sperm Analysis ◽

Progressive Motility ◽

Liquid Storage ◽

Before And After ◽

Boar Semen ◽

Casa System ◽

Sexually Mature ◽

Term Storage

The research was focused on the modern evaluation of boar semen parameters, using computer assisted sperm analysis (CASA), before and after liquid storage at 15ºC. Semen was collected from 15 sexually mature boars by manual stimulation. Macroscopical and microscopical evaluation of semen was performed, followed by a detailed CASA analysis of all ejaculates. Subsequently, semen was diluted using 4 different extenders (Semtest, Androstar, MIII and Cronos) and stored at 15ºC for 24 hours. Next, evaluation of progressive motility, total motility and viability was performed, using the same CASA system. All experiments were performed in triplicates and results were statistically analyzed. The average progressive motility after 24 hours was as follows: 69.56 ± 6.38 for MIII, 65.92% ± 2.63 for Semtest, 67.07% ± 5.58 for Androstar Plus and 68.93% ± 3.40 for Cronos. The viability results after 24 hours were: 86.34% ± 1.38 for Semtest extender, 93.55% ± 3.38% for Androstrar Plus, 89.19% ± 3.42 for MIII and 91.35% ± 2.37 for Cronos. The findings of this study suggest that the use of commercial extenders for short-term storage of swine semen is important in order to increase sperm longevity with minimal sperm function deterioration.

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Assessment of an iPad-based Sperm Motility Analyzer for Determination of Canine Sperm Motility

Translational Animal Science ◽

10.1093/tas/txab066 ◽

2021 ◽

Author(s):

Evelyn Bulkeley ◽

Christine Collins ◽

Azarene Foutouhi ◽

Kris Gonzales ◽

Heather Power ◽

...

Keyword(s):

Sperm Motility ◽

Semen Analysis ◽

Computer Assisted ◽

Sperm Analysis ◽

Progressive Motility ◽

Alternative Measurement ◽

Positive Correlations ◽

Casa System ◽

Progressive Assessment

Abstract The objective of this study was to evaluate the repeatability and accuracy of canine sperm motility (total and progressive) assessment with a tablet-based Canine iSperm ® instrument compared to computer-assisted sperm analysis (CASA). The experiment used fresh and frozen/thawed canine semen samples for comparisons of semen analysis parameters (concentration, total motility, and progressive motility) between a CASA system, iSperm ®, and NucleoCounter ® SP-100 ™ (concentration) instruments. Spearman’s Rho correlational analysis was used to identify significant associations between motility assessment methods. Significant positive correlations were found between CASA assessment and iSperm ® for both progressive and total motility measurements. We also determined the coefficient of variation (CV) for repeatability of sample analysis for iSperm ® and CASA for fresh sperm, wherein each sample was assessed 10 times on both devices. For fresh and frozen-thawed samples, concentration assessment by iSperm ® showed high variability (CV= 19.9 ± 1.5%). For iSperm ® assessment of total and progressive motility, the CV’s were 6.3 ± 0.5% and 10.7 ± 0.8%, respectively. The results indicate that the iSperm ® application offers an accurate and alternative measurement of motility to traditional CASA analysis, though caution should be taken when assessing concentration due to the high CV observed in this study.

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76 COMPUTER-ASSISTED SPERM ANALYSIS OF FROZEN SPERM MOTILITY AFTER DIFFERENT TIMES OF EXPOSURE AT 15°C

Reproduction Fertility and Development ◽

10.1071/rdv20n1ab76 ◽

2008 ◽

Vol 20 (1) ◽

pp. 119

Author(s):

A. Garcia Guerra ◽

M. P. Etcheverry ◽

D. Rodriguez ◽

G. Larraburu ◽

G. M. Brogliatti

Keyword(s):

Liquid Nitrogen ◽

Sperm Motility ◽

Room Temperature ◽

Cell Damage ◽

Semen Analysis ◽

Beat Frequency ◽

Computer Assisted ◽

Frozen Semen ◽

Significant Difference ◽

Casa System

One of the key factors for successful long-term cryopreservation in liquid nitrogen is maintaining the samples at –130°C or lower at all times to avoid cell damage (Barth 1991 Proc. 10th Ann. Conv. Am. Embr. Transf. Assoc., 20–26). Previous data indicated that exposure of the semen straw to ambient temperature for more than 15 s can raise the temperature above –130°C and reduce sperm motility, as determined by subjective evaluation (Berndtson et al. 1976 Proc. 6th NAAB Tech. Conf. Artif. Insem. Reprod., 51–60). The computer-assisted semen analysis (CASA) system provides an opportunity to assess multiple motility characteristics on a semen sample objectively and with high repeatability. An experiment was designed to evaluate the effect of exposing frozen semen in 0.5-mL straws to room temperature for 15, 30, 60, or 120 s on motility characteristics assessed by CASA system. Twenty-eight ejaculates from different bulls (19 Angus, 7 Hereford, 1 Brangus, 1 Shorthorn) were diluted using a chemically semi-defined media (Andromed, Minitüb, Tiefenbach, Germany) and frozen in an automatic freezer (Digicool, IMV, Paillette Crista, France). Five frozen straws per bull were used, one for each time of exposure and one as control (0 s = 0 time). Straws were exposed to room temperature (15°C ± 0.78) for different times and then placed back into liquid nitrogen. Semen thawing was conducted in a water bath at 37°C for 1 min. Motility characteristics were evaluated by the IVOS SpermAnalyzer (Hamilton Thorne Research, Beverly, MA, USA). Two chambers of 20-μm depth and 5 fields per chamber were analyzed (30 frames/0.5 s for each field). Seven motility parameters were evaluated: motile sperm (%), progressive sperm (%), VAP (path velocity, μm s–1), VCL (track speed, μm s–1), ALH (lateral amplitude, μm), BCF (beat frequency, Hz), and LIN (Linearity, %). The Kruskal–Wallis test was used to compare variables among groups, and results are shown in Table 1. There is a significant difference (P < 0.05) in the % of motile and progressive sperm when time of exposure was increased. There was a drastic and significant reduction in the percentage of motile and progressive sperm when exposure to 15°C was longer than 30 s. The live cells had similar motile characteristics: VAP, VCL, ALH, BCF, and LIN. In conclusion, sperm motility would be affected if straws are exposed for more than 30 s. More research should be done to test higher room temperatures, detect viability effects, and determine pregnancy rates after AI. Table 1. CASA of frozen sperm motility characteristics at different times of exposure at 15°C This research was supported by Centro Genetico Bovino Eolia S.A.

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Influence of chamber type integrated with computer-assisted semen analysis (CASA) system on the results of boar semen evaluation

Polish Journal of Veterinary Sciences ◽

10.1515/pjvs-2015-0106 ◽

2015 ◽

Vol 18 (4) ◽

pp. 817-824 ◽

Cited By ~ 6

Author(s):

D. Gączarzewicz

Keyword(s):

Semen Analysis ◽

Sperm Concentration ◽

Computer Assisted ◽

Head Displacement ◽

Manual Counting ◽

Boar Semen ◽

Casa System ◽

Microscopic Slide ◽

Lateral Head ◽

Sperm Movement

Abstract The objective of the study was to evaluate the effect of different types of chambers used in computer-assisted semen analysis (CASA) on boar sperm concentration and motility parameters. CASA measurements were performed on 45 ejaculates by comparing three commonly used chambers: Leja chamber (LJ), Makler chamber (MK) and microscopic slide-coverslip (SL). Concentration results obtained with CASA were verified by manual counting on a Bürker hemocytometer (BH). No significant differences were found between the concentrations determined with BH vs. LJ and SL, whereas higher (p<0.01) values of this parameter were obtained with MK. Compared to MK and SL, significantly higher values were recorded in LJ for velocity (VCL and VAP) as well as amplitude of the lateral head displacement (ALH) and beat cross frequency (BCF), which was associated with significantly higher percentages of motile, progressively motile and rapidly progressive motile spermatozoa. Higher values for the linearity (LIN) and straightness (STR) of sperm movement were obtained for the analysis performed in MK and SL. In both these chambers, the results of all the linearity and kinetic parameters of sperm were similar (p>0.05). The results obtained show that CASA assessment of boar semen should account for the effect of counting chamber on the results of sperm motility and concentration, which confirms the need for further study on standardizing the automatic analysis of boar semen.

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Sistemas de análisis computadorizado de semen en la reproducción animal

Agronomía Mesoamericana ◽

10.15517/ma.v29i2.30613 ◽

2018 ◽

Vol 29 (2) ◽

pp. 469

Author(s):

Anthony Valverde Abarca ◽

Mónica Madrigal Valverde

Keyword(s):

Normal Distribution ◽

Artificial Insemination ◽

Semen Analysis ◽

Computer Assisted ◽

Considerable Variability ◽

Animal Reproduction ◽

Livestock Species ◽

The Relationship ◽

Sperm Population ◽

Issue Reports

Computer-assisted semen analysis (CASA) is used in animal reproduction with the objective of evaluating spermquality, quickly and reliably. Currently, artificial insemination centers must have reliable and objective systems thatensure the reliability of reproductive data. The aim of this paper was to review computer-assisted semen analysisin livestock species. The use of CASA systems replace routine quality analyzes that introduce biases and leads to different inaccuracy degrees. In addition, if intrinsic limitations of microscopy or sperm with different motilitypatterns are considered, it is most likely that considerable variability will be introduced which will have an impact on the objectivity of the estimation. At first, this type of technology was inaccessible, but they are currently used routinelyin most research laboratories for the evaluation of sperm samples of different species of zootechnical interest..Computerized techniques are able to issue reports with a high number of characteristics, to minimize the subjectivefactor of routine semen analysis, and to ensure a better correlation with the fertilizing capacity of spermatozoa by the relationship between sperm motility and functional competence. The use of CASA systems together with multivariatestatistical analysis have demonstrated the existence of kinetic and morphometric subpopulations in ejaculates ofdifferent species, eliminating the idea that ejaculates are homogeneous, formed by a single sperm population with normal distribution.

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Scanning x-ray fluorescence microscopy and principal component analysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100133394 ◽

1992 ◽

Vol 50 (2) ◽

pp. 1752-1753

Author(s):

Brian Cross

Keyword(s):

Principal Component Analysis ◽

Fluorescence Microscopy ◽

Spatial Resolution ◽

High Speed ◽

Image Acquisition ◽

Principal Component ◽

Fluorescence Microscope ◽

Acquisition Rate ◽

X Ray ◽

Speed Up

A relatively new entry, in the field of microscopy, is the Scanning X-Ray Fluorescence Microscope (SXRFM). Using this type of instrument (e.g. Kevex Omicron X-ray Microprobe), one can obtain multiple elemental x-ray images, from the analysis of materials which show heterogeneity. The SXRFM obtains images by collimating an x-ray beam (e.g. 100 μm diameter), and then scanning the sample with a high-speed x-y stage. To speed up the image acquisition, data is acquired "on-the-fly" by slew-scanning the stage along the x-axis, like a TV or SEM scan. To reduce the overhead from "fly-back," the images can be acquired by bi-directional scanning of the x-axis. This results in very little overhead with the re-positioning of the sample stage. The image acquisition rate is dominated by the x-ray acquisition rate. Therefore, the total x-ray image acquisition rate, using the SXRFM, is very comparable to an SEM. Although the x-ray spatial resolution of the SXRFM is worse than an SEM (say 100 vs. 2 μm), there are several other advantages.

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Влияние биологической полноценности спермы быков-производителей канадской селекции на репродуктивные показатели коров отдельного стада

Аграрная Россия ◽

10.30906/1999-5636-2017-2-18-21 ◽

2017 ◽

pp. 18-21

Author(s):

Александр Александрович Некрасов ◽

Николай Александрович Попов ◽

Байлар Садраддинович Иолчиев

Keyword(s):

Semen Analysis ◽

Computer Assisted

Исследовано влияние качества спермы быков-производителей на репродуктивные показатели стада. Материалом для исследования послужила замороженно-оттаянная сперма быков-производителей канадской селекции (n = 6), которую использовали для осеменения коров и телок на ферме «Дубровицы» ФГУП «Кленово-Чегодаево». Концентрацию и подвижность сперматозоидов оценивали с помощью компьютерной технологии Computer-assisted semen analysis (CASA). Состояние хроматина в сперматозоидах изучали методом акридин-оранжевого теста с флуоресцентной микроскопией. Морфологию и целостность акросом оценивали с использованием Дифф-Квик окраски. Всего на ферме «Дубровицы» плодотворно были осеменены 161 корова и 29 телок, от них получены 180 телят, из них 97 бычков и 83 телки. Установлено, что одним из биотических факторов, влияющих на репродуктивные показатели, является состояние ДНК в хроматине. От степени фрагментации ДНК в хроматине сперматозоидов зависит их оплодотворяющая способность и другие показатели фертильности быков-производителей. Уровень воспроизведения обусловлен репродуктивным потенциалом как коров, так и быков-производителей. Для комплексной оценки качества спермы быков-производителей необходимо использовать компьютерные технологии с привлечением максимального числа показателей, в том числе наследственного материала, содержащегося в сперматозоидах. Целесообразно при оценке быков-производителей вести учет благополучия отелов, выбытия коров после патологических отелов, абортов, мертворождаемости. Благополучие отелов способствует увеличению сроков последующего производственного использования коров, осемененных спермой быков-производителей, характеризующихся легкими отелами. Для достоверной оценки биологической полноценности спермы необходимо использовать дополнительный показатель, а именно степень фрагментации ДНК в хроматине. У быков-производителей с высокой степенью фрагментации ДНК получены низкие результаты оплодотворяемости.

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Modeling the Radial Stem Growth of the Pine (Pinus sylvestris L.) Forests Using the Satellite-Derived NDVI and LST (MODIS/AQUA) Data

Atmosphere ◽

10.3390/atmos12010012 ◽

2020 ◽

Vol 12 (1) ◽

pp. 12

Author(s):

Yulia Ivanova ◽

Anton Kovalev ◽

Vlad Soukhovolsky

Keyword(s):

Land Surface ◽

Vegetation Index ◽

Normalized Difference Vegetation Index ◽

Principal Component ◽

Stem Growth ◽

Forest Growth ◽

Parabolic Approximation ◽

New Approach ◽

The Relationship ◽

Tree Increment

The paper considers a new approach to modeling the relationship between the increase in woody phytomass in the pine forest and satellite-derived Normalized Difference Vegetation Index (NDVI) and Land Surface Temperature (LST) (MODIS/AQUA) data. The developed model combines the phenological and forest growth processes. For the analysis, NDVI and LST (MODIS) satellite data were used together with the measurements of tree-ring widths (TRW). NDVI data contain features of each growing season. The models include parameters of parabolic approximation of NDVI and LST time series transformed using principal component analysis. The study shows that the current rate of TRW is determined by the total values of principal components of the satellite indices over the season and the rate of tree increment in the preceding year.

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Factors influencing the occurrence of negative interactions between people and crocodilians in Mexico

Oryx ◽

10.1017/s0030605319000668 ◽

2021 ◽

pp. 1-9

Author(s):

Giovany Arturo González-Desales ◽

Luis Sigler ◽

Jesús García-Grajales ◽

Pierre Charruau ◽

Martha Mariela Zarco-González ◽

...

Keyword(s):

Anthropogenic Activities ◽

Biosphere Reserve ◽

Rigorous Evaluation ◽

Caiman Crocodilus ◽

Crocodylus Acutus ◽

American Crocodile ◽

Nesting Sites ◽

The Relationship ◽

Nesting Season ◽

Negative Interactions

Abstract Negative interactions between people and crocodilians have increased worldwide, but in Mexico there have been few systematic reports and no rigorous evaluation of this problem. We compiled information on negative interactions between people and the spectacled caiman Caiman crocodilus and American crocodile Crocodylus acutus from the Worldwide Crocodilian Attack Database for 1993–2018, and we investigated interactions in greater depth, through interviews with people in La Encrucijada Biosphere Reserve. We examined the relationship between the occurrence of negative interactions between people and C. acutus and the species' nesting season and abundance, and presence records. In Mexico, the frequency of negative interactions increases when anthropogenic activities occur close to nesting sites (< 30 km) and during the nesting season (February–September). In La Encrucijada, following negative interactions with crocodiles, the local inhabitants killed 30 crocodiles measuring > 2.5 m long in 2011–2012. The frequency of negative human–crocodilian interactions was not correlated with the abundance of crocodilians but was correlated with the number of presence records of crocodiles. Strategies to minimize these interactions include warnings at nesting sites, increased monitoring of anthropogenic activities during the nesting season, and management of nests to prevent them being destroyed by people.

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