PRELIMINARY RESULTS OF INTRA CYTOPLASMIC SPERM INJECTION (ICSI) APPLIED ON RABBIT : A TECHNICAL NOTE

[EN] In a foundation process of a maternal rabbit line using high selection intensities, from sorne hyper prolific females, selected as embryo donors, the subjects were very old and in an unhealthy condition (24%). An in vitro procedure to obtain embryos from this kind of females would be desirable. Sorne technical improvements used for human intracytoplasmic sperm injection (ICSI) have resulted in an enhancement of cleavage rates. This method may be applied to rabbits. Spermatozoa from ejaculated washed semen samples were immobilised in 5% PVP droplet by touching the tail and aspirated tail first into the microinjection pipette. The positioned oocyte was punctured. Sorne ooplasm was aspirated. After rupturing the plasmalema by gentle aspiration, the withdrawn ooplasm and the sperm were inserted into the oocyte. The cleavage rate of intact (86/107; 80%) oocytes was checked at 24 hours after ICSI (39/107; 36%). In vitro development up to the morulae (22/39; 56%) and blastocyst stage (5/39; 13%) were obtained.[FR] Chez le tapín, dans la procédure permettant d'obtenir une lignée matemeUe en uti/isant la sé/ection intensive á partir de femeUes tres prolifiques, sé/ectionnées comme donneuses d'embryons, les animaux deviennent trop llgés et sont dans de mauvaises conditions sanitaires (24%). 11 paraft préférable d'utiliser un procédé in vitro pour obtenir les embryons de teUes femeUes. Des améliorations techniques utilisées pour l'injection intracytop/asmique du sperme chez f'homme (ICSI) ont amé/ioré le taux de division. Cette méthode peut étre app/iquée chez le tapín. Les spermatozordes provenant d'échantiUons d'éjaculats lavés sont immobilisés, dans une goutte d'une so/ution contenant 5% de PVP, en touchant la queue et en les aspírant par la queue dans une micro pípette á injection. L'ovocyte repéré est ponctionné. Un peu d'ovop/asme est aspiré. Aprés avoir rompu le p/asmalema par une /égére aspiration, /'ovop/asme et le sperme sont injectés dans /'ovocyte. Le taux de division d'ovocytes intacts (861107 ; 80%) est contrO/e 24 heures apres l'/CSI (391107; 36%). Le développement in vitro jusqu'au stade morula (22139; 56%) et blastocyste (5139; 13%) a été atteint.This work was supported by CICYT AGF95-0850 and Conselleria de Educación y ciencia de la Comunidad Valenciana. We wish to thank Mr. Neil Macowan for help with the English version230Escribá, M.; García- Ximénez, F. (1999). PRELIMINARY RESULTS OF INTRA CYTOPLASMIC SPERM INJECTION (ICSI) APPLIED ON RABBIT : A TECHNICAL NOTE. World Rabbit Science. 06(2). https://doi.org/10.4995/wrs.1998.348SWORD22706

DIFFERENT SERUM COMPLEMENTS AFFECT THE IN VITRO DEVELOPMENT AND HATCHING RATES OF RABBIT ZYGOTES. A TECHNICAL NOTE

[EN] The effect of two different types of serum supplements l Ham's F-1 O medium on the development of rabbit zygotes to the 1lastocyst stage was tested. The in vitro development was improved ihen ovulated-doe serum, instead young-rabbit serum was added to lam's F-10 medium. The development to the 16-cell, compactad norula-early blastocyst, blastocyst or hatched stage at 24, 48 and 168 hours of culture were 44%, 54%, 100% and 92% vs 0%, 19%, 75% and 56%, respectively. Moreover, the established conditions of culture (39•C, 7% co2 in air and 15 mM sodium bicarbonate) associated with the ovulated-doe serum in Ham's F-1 O could enhance the in vítro development of rabbit zygotes up to the hatching stage (90-100%).[FR] .es auteurs ont comparé 2 types de sérums de lapin pour :omplémenter le mílieu Ham F-1 O /ors de la culture in vitro f'embryons fécondés de lapins. Les sérums provenaient soit de wnes lapins (9 semaines) soit de Japines adu/tes ayant ovulé. Le féveloppement des zygotes in vitro est possible avec les 2 :upplémentations, mais est nettement favorisé par l'utilisation de :érum de lapine ayant ovulé. Avec ce dernier, les stades de développement 16-cellu/es (en 24h), moru/a (48h), blastocyste et blastocyste maturé (en 16h) ont été atteints par 44%, 54%, 100% et 92% des oeufs fécondés, respectívement, contre seu/ement 0%, 19%, 75% et 56% avec le sérum de jeune lapin. Ainsi, les conditions de culture adaptées (3!l'C, 7% de C02 dans l'air et 15mM de bicarbonate de sodium) et l'usage du sérum de lapine ayant ovulé permettent d'obtenir un développement in vitro de 90% a 100% des oeufs de lapin fécondés jusqu'au stade blastocyste mature, ce qui n'est pas réalisé avec les supplémentatíons c/assiques avec du sérum bovin.This work was supported by CICYT AGF94-0577 and conselleria de Educación y ciencia de la C.V. We wish to thank Ms. Barraglough and Mr. donnellan for help with the English212Escribá, M.; García-Ximénez, F. (1998). DIFFERENT SERUM COMPLEMENTS AFFECT THE IN VITRO DEVELOPMENT AND HATCHING RATES OF RABBIT ZYGOTES. A TECHNICAL NOTE. World Rabbit Science. 06(1). doi:10.4995/wrs.1998.345SWORD20906

La efectividad de la inversión en infraestructuras públicas: una panorámica para la economía española y sus regiones

En este trabajo se realiza una revisión de la literatura económica de los últimos años que ha abordado la cuantificación de los efectos macroeconómicos de las infraestructuras públicas, especialmente en el ámbito regional. El trabajo ofrece una visión de cuáles han sido, desde el punto de vista de los autores, las contribuciones y los planteamientos más significativos dentro de los enfoques de funciones de producción y de costes. En el análisis se pone el énfasis en los resultados obtenidos para el caso particular de la economía española. Asimismo, las conclusiones están íntegramente dedicadas a extraer algunas recomendaciones que deberían tenerse en cuenta en el futuro, a la hora de llevar a cabo las políticas económicas de inversión pública en infraestructuras en España

Economic and statistical measurement of physical capital: From theory to practice

The standard measurements of capital and depreciation are statistical measures based on assumptions about the average service life of capital goods, which are accumulated according to the perpetual inventory method. The purpose of this paper is to obtain a true economic measure of capital stock according to the prescriptions of the neoclassical theory. In this way, we develop an alternative method based on the equations that solve the dynamic optimization problem of the firm, yielding an economic estimation based on indicators of profitability, such as the distributed profits and the Tobin's q ratio. Thus, this method enables us to endogenously calculate the variables' rate of depreciation and capital stock. We apply this procedure to the Spanish economy, getting the series of an economic measure of depreciation and the economic value of capital stock. Our results show an economic depreciation rate that fluctuates around the statistical rate. Moreover, we get two time profiles for the economic and statistical capital stocks that differ significantly from each other

Is Public Capital Productive? Evidence from a Meta-analysis

Debate exists over the role that public investment must play in economic recovery and economic growth. The underlying idea behind this debate has much to do with the value of output elasticity of public capital. This article presents a meta-analysis of this elasticity, which was performed by considering almost 2,000 elasticities previously estimated from 145 papers. In addition, for each elasticity, we also take into account some 30 associated features relative to the methodology used for each case or relative to the characteristics of data samples. The obtained results reveal an average short-term elasticity of 0.13 (0.16 in the long term). We also find evidence of the importance of the methodology adopted for the obtained results, as well as the publication bias. Finally, we find a minor reduction in the value of the elasticity as public capital endowments increase. The results obtained highlight the positive and important effect of public investment on productivity. As a results of the value obtained, public investment will be self-financed in the long-term because of generated returns. But, we also find that the effectiveness of public investment has a clear influence of the institutional context

Whole genome amplification in preimplantation genetic diagnosis*

Preimplantation genetic diagnosis (PGD) refers to a procedure for genetically analyzing embryos prior to implantation, improving the chance of conception for patients at high risk of transmitting specific inherited disorders. This method has been widely used for a large number of genetic disorders since the first successful application in the early 1990s. Polymerase chain reaction (PCR) and fluorescent in situ hybridization (FISH) are the two main methods in PGD, but there are some inevitable shortcomings limiting the scope of genetic diagnosis. Fortunately, different whole genome amplification (WGA) techniques have been developed to overcome these problems. Sufficient DNA can be amplified and multiple tasks which need abundant DNA can be performed. Moreover, WGA products can be analyzed as a template for multi-loci and multi-gene during the subsequent DNA analysis. In this review, we will focus on the currently available WGA techniques and their applications, as well as the new technical trends from WGA products