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Mata-Campuzano M.,University of Leon | Alvarez-Rodriguez M.,University of Leon | Alvarez M.,University of Leon | Anel L.,University of Leon | And 3 more authors.
Reproduction in Domestic Animals | Year: 2012

Contents: Thawed ram spermatozoa were incubated at 37°C in the presence of dehydroascorbic acid (DHA), TEMPOL (TPL), N-acetyl-cysteine (NAC) and rutin (RUT), at 0.1 and 1mm, in order to test their effects on sperm physiology. Cryopreserved spermatozoa from four rams were thawed, pooled, washed and incubated in TALP-Hepes with 1mm or 0.1mm of each antioxidant, performing a replicate with induced oxidative stress (Fe2+/ascorbate). Motility (CASA), viability and mitochondrial membrane potential (flow cytometry) were analysed at 2 and 4h. Lipoperoxidation (MDA production), intracellular reactive oxygen species (ROS) and DNA status (TUNEL) were analysed at 4h. Antioxidants, except DHA 0.1mm, decreased motility and kinematic parameters, but had little effect on viability or mitochondrial activity. Except 1mm DHA, the antioxidants reduced ROS at 4h. Moreover, NAC 1mm, rutin and TEMPOL reduced ROS and DNA damage in the presence of oxidative stress. N-acetyl-cysteine, rutin 1mm and TEMPOL reduced lipoperoxidation in the presence of oxidative stress. However, DHA did not affect lipoperoxidation. At 1mm, DHA increased DNA damage in the absence of oxidative stress. Dehydroascorbic acid effects could arise from spermatozoa having a low capacity for reducing it to ascorbic acid, and it may be tested in the presence of other antioxidants or reducing power. Future research should focus in testing whether the inhibition of motility observed for NAC, rutin and TEMPOL is reversible. These antioxidants might be useful at lower temperatures (refrigerated storage or cryopreservation) when their protective effects could be advantageous. © 2012 Blackwell Verlag GmbH.

Malo A.F.,Smithsonian Institution | Malo A.F.,Imperial College London | Martinez-Pastor F.,Chicago Zoological Society | Martinez-Pastor F.,University of Leon | And 4 more authors.
Biology of Reproduction | Year: 2010

Mice (Peromyscus leucopus noveboracensis) from a captive-breeding program were used to test the effects of three genetic breeding protocols (minimizing mean kinship [MK], random breeding, and selection for docility [DOC]) and inbreeding levels on sperm traits and fertility. Earlier, in generation 8, one DOC replicate went extinct because of poor reproductive success. By generation 10, spermatozoa from DOC mice had more acrosome and midpiece abnormalities, which were shown to be strong determinants of fertility, as well as lower sperm production and resistance to osmotic stress. In addition, determinants of fertility, including male and female components, were assessed in a comprehensive manner. Results showed that the probability (P) of siring litters is determined by sperm number, sperm viability, and midpiece and acrosome abnormalities; that the P of siring one versus two litters is determined by tail abnormalities; and that the total number of offspring is influenced by female size and proportion of normal sperm, showing the relative importance of different sperm traits on fertility. On average, males with 20% normal sperm sired one pup per litter, and males with 70% normal sperm sired eight pups per litter. Interestingly, the proportion of normal sperm was affected by docility but not by relatively low inbreeding. However, inbreeding depression in sperm motility was detected. In the MK group, inbreeding depression not only affected sperm motility but also fertility: An increase in the coefficient of inbreeding (f ) of 0.03 reduced sperm motility by 30% and translated into an offspring reduction of three pups in second litters. A genetic load of 48 fecundity equivalents was calculated. © 2010 by the Society for the Study of Reproduction, Inc.

Martinez-Pastor F.,University of Leon | Tizado E.J.,University of Leon | Garde J.J.,National Wildlife Research Institute IREC | Anel L.,University of Leon | de Paz P.,University of Leon
Theriogenology | Year: 2011

Computer-assisted sperm analysis (CASA) allows assessing the motility of individual spermatozoa, generating huge datasets. These datasets can be analyzed using data mining techniques such as cluster analysis, to group the spermatozoa in subpopulations with biological meaning. This review considers the use of statistical techniques for clustering CASA data, their challenges and possibilities. There are many clustering approaches potentially useful for grouping sperm motility data, but some options may be more appropriate than others. Future development should focus not only in improvements of subpopulation analysis, but also in finding consistent biological meanings for these subpopulations. © 2011 Elsevier Inc.

Castro-Gonzalez D.,University of Leon | Alvarez M.,University of Leon | Muro J.,University of Leon | Esteso M.C.,National Wildlife Research Institute IREC | And 3 more authors.
Reproduction in Domestic Animals | Year: 2010

To try new acrosomal probes for assessing ram spermatozoa, we compared the LysoSensor™ probe, which labels acidic organelles, with the frequently used peanut agglutinin acrosomal probe (PNA-PE; phycoerythrin as fluorescent moiety). The previous microscopic observations showed a lack of relationship of LysoSensor™ with acrosomal status. Semen was obtained from five rams and frozen in four pools. Each pool was analysed carrying out a triple staining propidium ioide/PNA-PE/LysoSensor™ Green DND-189 to test acrosome labelling, and a double staining SYBR-14/PI, to assess sperm viability. Stained samples were analysed by flow cytometry. All measurements were replicated. Data were processed using agreement and repeatability tests. LysoSensor™ labelling did not agree with PNA (mean of differences: 30.8%; coefficient of agreement: 22.6%), confirming microscopic observations. Nevertheless, when LysoSensor™ was compared with SYBR-14/PI, the agreement was high (mean of differences: -0.05%; coefficient of agreement: 5.07%). Repeatability of both methods was high and similar. LysoSensor™ did not seem to specifically stain the acrosome, but it may accumulate in the cytoplasm and label viable spermatozoa. Therefore, LysoSensor™ might not be used as an acrosomal probe in ram spermatozoa, but it could be used in other kind of studies, taking advantage of its pH sensitivity. © 2009 Blackwell Verlag GmbH.

Maroto-Morales A.,National Wildlife Research Institute IREC | Berlinguer F.,University of Sassari | Fernandez-Santos M.R.,National Wildlife Research Institute IREC | Fernandez-Santos M.R.,Institute of Regional Development IDR | And 7 more authors.
Theriogenology | Year: 2011

The aim of this work was to study the effect of storage temperature during the transport of ovaries on cleavage and blastocyst rates in Iberian red deer, because wild populations of this subspecies are usually far from laboratories. A total of 472 ovaries from 236 Iberian hinds were recovered and maintained in saline solution at 5-8 °C or 20-25 °C for 12 h. After storage, aspirated oocytes were matured with FSH/LH or EGF and the developed embryos were cultured with oviduct epithelial cells monolayer (OCM). A higher (P = 0.009) cleavage rate was obtained when the ovaries were stored at 5-8 °C. However, there were no differences between both storage temperatures in relation to the percentage of blastocysts obtained. Considering the management and production systems of Iberian red deer, this study provides important information about the ovary storage temperature during transport with the purpose of assuring an optimal in vitro embryo production. © 2011 Elsevier Inc.

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