Intramale variation in spermsize: functional significance in a polygynous mammal

Studies concerning the relationships between sperm size and velocity at the intraspecific level are quite limited and often yielded contradictory results across the animal kingdom. Intramale variation in sperm size may represent a meaningful factor to predict sperm velocity, due to its relationship with the level of sperm competition among related taxa. Because spermphenotype is under post-copulatory sexual selection, we hypothesized that a reduced intramale variation in sperm size is associated with sperm competitiveness in red deer. Our results show that low variation in sperm size is strongly related to high sperm velocity and normal sperm morphology, which in turn are good predictors of male fertility in this species. Furthermore, it is well known that the red deer show high variability in testicular mass but there is limited knowledge concerning the significance of this phenomenon at intraspecific level, even though it may reveal interesting processes of sexual selection. Thereby, as a preliminary result, we found that absolute testes mass is negatively associated with intramale variation in sperm size. Our findings suggest that sperm size variation in red deer is under a strong selective force leading to increase sperm function efficiency, and reveal new insights into sexual selection mechanisms.Czech University of Life Sciences CIGA 20145001. JLRS and EP were supported by the project CIGA 20145001 (Czech University of Life Sciences, Prague, Czech Republic).Peer Reviewe

Diagnosis value of fine needle aspiration cytology in testicular disorders of red deer (Cervus elaphus): a case report

We used fine needle aspiration cytology (FNAC) to diagnose Sertoli cell-only pattern and hypospermatogenesis in an Iberian red deer (Cervus elaphus hispanicus). Cytologic diagnosis was confirmed by histology and epididymal sperm analysis. We conclude that FNAC can be an important diagnostic tool in testicular diseases of wildlife.Eliana Pintus and José Luis Ros-Santaella are supported by grants CIGA 20145001 and 99830/1181/1822 (Czech University of Life Sciences).Peer Reviewe

Sperm flagellum volume determines freezability in red deer spermatozoa

The factors affecting the inter-individual differences in sperm freezability is a major line of research in spermatology. Poor sperm freezability is mainly characterised by a low sperm velocity, which in turn is associated with low fertility rates in most animal species. Studies concerning the implications of sperm morphometry on freezability are quite limited, and most of them are based on sperm head size regardless of the structural parts of the flagellum, which provides sperm motility. Here, for the first time, we determined the volumes of the flagellum structures in fresh epididymal red deer spermatozoa using a stereological method under phase contrast microscopy. Sperm samples from thirty-three stags were frozen and classified, as good freezers (GF) or bad freezers (BF) at two hours post-thawing using three sperm kinetic parameters which are strongly correlated with fertility in this species. Fourteen stags were clearly identified as GF, whereas nineteen were BF. No significant difference in sperm head size between the two groups was found. On the contrary, the GF exhibited a lower principal piece volume than the BF (6.13 μm3 vs 6.61 μm3, respectively, p = 0.006). The volume of the flagellum structures showed a strong negative relationship with post-thawing sperm velocity. For instance, the volume of the sperm principal piece was negatively correlated with sperm velocity at two hours post-thawing (r = -0.60; p<0.001). Our results clearly show that a higher volume of the sperm principal piece results in poor freezability, and highlights the key role of flagellum size in sperm cryopreservation success.JLRS was supported by I3P program (Spanish National Research Council, CSIC, Spain), post-doctoral fellowship no. 99830/1181/1822 (Czech University of Life Sciences, Prague, Czech Republic), and by the project CIGA 20145001 (Czech University of Life Sciences, Prague, Czech Republic).Peer Reviewe

REFLEXIONES SOBRE EL DISEÑO DE UNA POLÍTICA INSTITUCIONAL DE OPEN SCIENCE E IMPLICACIONES DE SU IMPLANTACIÓN

El presente trabajo tiene como objetivo exponer las reflexiones realizadas para definir las principales guías en el diseño e implantación de la política institucional de Open Science -OS- en la Universidad de Castilla-La Mancha -UCLM- para que ésta sea congruente con los compromisos adquiridos con la adhesión a la Declaración de Berlín y, en los últimos meses, con la asunción de los compromisos CRUE ante la OS. Partiendo del marco de obligaciones actual, derivado de los mandatos de ámbito nacional y europeo, y del diagnóstico de la situación de Open Access a partir de las estadísticas del repositorio institucional de la UCLM RUIdeRA (exclusivamente depósitos de publicaciones de investigación: artículos y tesis doctorales) intentaremos determinar la efectividad de los mandatos externos y la necesidad y conveniencia de diseñar nuestra política institucional de OS en términos de recomendación o requerimiento. Así mismo, se analizarán las implicaciones organizativas y económicas que podrían derivarse de la implantación y cuya anticipación modela la política de Ciencia Abierta a desarrollar. The present paper exposes some reflections made to define the main guidelines in the design and implementation of the Open Science institutional policy at the University of Castilla-La Mancha -UCLM-. This policy should be consistent with the commitments made with the adherence to the Berlin Declaration and, recently, with the assumption of CRUE commitments to the Open Science. Starting from the framework of current obligations, based on the mandates of National and European level, and on the diagnosis of the Open Access situation from the statistics of the institutional repository of the UCLM RUIdeRA (deposits of research publications exclusively: articles and doctoral theses), this paper tries to determine the success of those external mandates and the need and convenience of designing our own Open Science Institutional Policy in terms of recommendation or in terms of requirement. Furthermore, the organizational and economic implications that could be developed from its implementation are analysed

Heterozygosity-fitness correlations and inbreeding depression in two critically endangered mammals

The relation among inbreeding, heterozygosity, and fitness has been studied primarily among outbred populations, and little is known about these phenomena in endangered populations. Most researchers conclude that the relation between coefficient of inbreeding estimated from pedigrees and fitness traits (inbreeding-fitness correlations) better reflects inbreeding depression than the relation between marker heterozygosity and fitness traits (heterozygosity-fitness correlations). However, it has been suggested recently that heterozygosity-fitness correlations should only be expected when inbreeding generates extensive identity disequilibrium (correlations in heterozygosity and homozygosity across loci throughout the genome). We tested this hypothesis in Mohor gazelle (Gazella dama mhorr) and Iberian lynx (Lynx pardinus). For Mohor gazelle, we calculated the inbreeding coefficient and measured heterozygosity at 17 microsatellite loci. For Iberian lynx, we measured heterozygosity at 36 microsatellite loci. In both species we estimated semen quality, a phenotypic trait directly related to fitness that is controlled by many loci and is affected by inbreeding depression. Both species showed evidence of extensive identity disequilibrium, and in both species heterozygosity was associated with semen quality. In the Iberian lynx the low proportion of normal sperm associated with low levels of heterozygosity was so extreme that it is likely to limit the fertility of males. In Mohor gazelle, although heterozygosity was associated with semen quality, inbreeding coefficient was not. This result suggests that when coefficient of inbreeding is calculated on the basis of a genealogy that begins after a long history of inbreeding, the coefficient of inbreeding fails to capture previous demographic information because it is a poor estimator of accumulated individual inbreeding. We conclude that among highly endangered species with extensive identity disequilibrium, examination of heterozygosity-fitness correlations may be an effective way to detect inbreeding depression, whereas inbreeding-fitness correlations may be poor indicators of inbreeding depression if the pedigree does not accurately reflect the history of inbreeding.Peer Reviewe

A cost for high levels of sperm competition in rodents: Increased sperm DNA fragmentation

Spermcompetition, a prevalent evolutionary process inwhich the spermatozoa of two or more males compete for the fertilization of the same ovum, leads to morphological and physiological adaptations, including increases in energetic metabolism that may serve to propel sperm faster but that may have negative effects onDNA integrity. SpermDNA damage is associated with reduced rates of fertilization, embryo and fetal loss, offspring mortality, and mutations leading to genetic disease. We tested whether high levels of sperm competition affect sperm DNA integrity. We evaluated sperm DNA integrity in 18 species of rodents that differ in their levels of spermcompetition using the spermchromatin structure assay. DNA integrity was assessed upon sperm collection, in response to incubation under capacitating or non-capacitating conditions, and after exposure to physical and chemical stressors. Sperm DNA was very resistant to physical and chemical stressors, whereas incubation in noncapacitating and capacitating conditions resulted in only a small increase in spermDNA damage. Importantly, levels of spermcompetition were positively associated with sperm DNA fragmentation across rodent species. This is the first evidence showing that high levels of sperm competition lead to an important cost in the form of increased sperm DNA damage.Peer Reviewe

Influence of the temperature and the genotype of the HSP90AA1 gene over sperm chromatin stability in Manchega rams

The present study addresses the effect of heat stress on males' reproduction ability. For that, we have evaluated the sperm DNA fragmentation (DFI) by SCSA of ejaculates incubated at 37°C during 0, 24 and 48 hours after its collection, as a way to mimic the temperature circumstances to which spermatozoa will be subject to in the ewe uterus. The effects of temperature and temperature-humidity index (THI) from day 60 prior collection to the date of semen collection on DFI were examined. To better understand the causes determining the sensitivity of spermatozoa to heat, this study was conducted in 60 males with alternative genotypes for the SNP G/C-660 of the HSP90AA1 promoter, which encode for the Hsp90α protein. The Hsp90α protein predominates in the brain and testis, and its role in spermatogenesis has been described in several species. Ridge regression analyses showed that days 29 to 35 and 7 to 14 before sperm collection (bsc) were the most critical regarding the effect of heat stress over DFI values. Mixed model analyses revealed that DFI increases over a threshold of 30°C for maximum temperature and 22 for THI at days 29 to 35 and 7 to 14 bsc only in animals carrying the GG-660 genotype. The period 29-35 bsc coincide with the meiosis I process for which the effect of the Hsp90α has been described in mice. The period 7-14 bsc may correspond with later stages of the meiosis II and early stages of epididymal maturation in which the replacement of histones by protamines occurs. Because of GG-660 genotype has been associated to lower levels of HSP90AA1 expression, suboptimal amounts of HSP90AA1 mRNA in GG-660 animals under heat stress conditions make spermatozoa DNA more susceptible to be fragmented. Thus, selecting against the GG-660 genotype could decrease the DNA fragmentation and spermatozoa thermal susceptibility in the heat season, and its putative subsequent fertility gains.This work was supported by RTA2009-00098-00-00 INIA project (Subprograma de Investigación Fundamental orientada a los Recursos y Tecnologías Agrarias).Peer Reviewe

Milk production and composition in captive Iberian red deer (Cervus elaphus hispanicus): effect of birth date

This study describes milk production and milk composition of Iberian red deer (Cervus elaphus hispanicus) females (hinds) and the effect of calving date andBWchange of hinds by milking over 34 wk. All hinds produced milk throughout the 34-wk study period, well over the standard lactation period. Total milk yield was 224.1 ± 21.1 L, and daily production was 0.91 ± 0.06 L. Milk yield decreased with lactation stage (P = 0.01) and the later a calf was born (P = 0.008), and it was greater in posterior quarters (P < 0.05). Milk yield was unaffected (P > 0.10) by side position or milking order of the udder. Milk production did not correlate with hind BW (P > 0.1). Hinds lost 4.4% BW during lactation (P < 0.001); losses increased the later a calf was born (P = 0.012). Iberian red deer milk had 11.5% fat, 7.6% protein, 5.9% lactose, and 26.7% DM. Stage of lactation affected fat (P < 0.001), protein (P = 0.002), DM (P < 0.001), and protein:fat ratio (P < 0.001), but not lactose (P > 0.1). These constituents became concentrated as lactation proceeded, and protein was substituted by fat. Calving date had a similar concentrating effect on fat (P 0.10). Results suggest that milk production and milk energetic quality might increase by advancing calving date in red deer hinds

Sperm population structure and male fertility: An intraspecific study of sperm design and velocity in Red Deer

Sperm design and velocity play key roles in influencing sperm performance and, therefore, can determine fertilization success. Several interspecific studies have demonstrated how these features correlate, and it has been hypothesized that selection may drive changes in these sperm traits. Here, we examine the association between sperm design and swimming velocity in a study conducted at an intraspecific level in Iberian red deer (Cervus elaphus hispanicus). We addressed how the structure of different sperm subpopulations, based on sperm morphometry and velocity, are interrelated and, in turn, how they associate with fertility. Our results show that males with high fertility rates have ejaculates with high percentages of spermatozoa exhibiting fast and linear movements and that these are highly correlated with a large proportion of spermatozoa having small and elongated heads. On the other hand, males with low fertility are characterized by a subpopulation structure in which slow and nonlinear as well as small and wide spermatozoa are predominant. These findings provide insight regarding how sperm size and velocity are interrelated and how they both are associated with fertility. © 2013 by the Society for the Study of Reproduction, Inc.Peer Reviewe