Relationships between depth and age, and recruitment indexes of hake on Galicia and Portugal shelf

In this paper it is studied the relations between the depth and the ages of the hake caugth in the six surveys done between 1974 and 1979 in the Divisions Vlllc and IXa, as soon as the recruitment levels in those years. It is observed a clear stratification of the ages and a significant bathimetric tendency to increase the mean age with the depth (1'=0.81). On the other hand, it is noticed a serious decrease in the following years over the recruitment level detected in 1974.Dans ce papier on a studie les relations entre l'âge et la profundeur du merlu capturée pendant six campagns realisées entre 1974 et 1979 dans subaire Vlllc et Division IXa du CIEM ainsi que les nivenux du recruitment durant ces annees. On observe une claire stratification entre la bathymetrie et l'âge et une tendence significatif a augmenter l'âge moyenne avec la profunder (r=0.81). D'antre coté, on constante une grave chute dans 1es anneés suivantes un relation avec le niveaux de recruitement detecté en 1974

Energy optimization of supplied flows from multiple pumping stations in water distributions networks

[EN] One of the most important concerns within the field of urban hydraulic engineers is the right management of water resources. When there is more than one water source, there is a question that must be answered: How much water should be provided by each water source according to the demand curve of the network? This work proposes a methodology that solves this question. It involves an energy analysis of the water network based on the concept of the setpoint curve. The setpoint curve gives, for every supplied flow, the minimum head needed to satisfy pressure requirements in the network. In this sense, the setpoint curve of every source relates two variables: supplied flow and minimum required head. Energy consumption in every source is evaluated by means of the product of these two variables. Then flow distribution among sources is optimized and minimum heads are obtained from the setpoint curve. The optimization process has been validated in two different ways. On one hand, a discrete method has been used, where a predefined combination of flow distributions are evaluated. On the other hand, the solution is found by means of Hooke-Jeeves and Nelder-Mead optimization algorithms. To apply these methods EPANET and its Toolkit has been applied to the mathematical model of the network. The optimization process can be applied to networks models with and without leakages. Finally, the methodology is applied to two cases, one academic network and real network where maximum flow limitations of every source were also taken into account.León Celi, CF.; Iglesias Rey, PL.; Martínez-Solano, FJ. (2017). Energy optimization of supplied flows from multiple pumping stations in water distributions networks. Procedia Engineering. 186:93-100. doi:10.1016/j.proeng.2017.03.214S9310018

Primer estudio de la pesquería demersal de Grand Sole y el oeste de Irlanda para la flota española

En el presente trabajo se hace un análisis detallado de la flota española en la pesquería demersal del Grand Sole y costas de Irlanda y que tiene su base en los puertos de Vigo, La Coruña. Pasajes y Ondárroa. Se dan sus zonas de pesca, captura, esfuerzo, rendimiento de pesca y estacionalidad de las especies más importantes (merluza, rapante, rape y cigala). Damos, asimismo. los resultados de los muestreos biológicos de tallas de merluza, realizados en los dos puertos gallegos y los tantos por ciento estimados para cada edad en la captura.In this paper the authors study thoroughly the Spanish fleet fhishing on the Grand Sole bank and off the Irish coast, whose home ports are Vigo, La Coruña, Ondárroa and Pasajes. Data are given about their fishing grounds, catches, effort and seasonal distribution of the main species sought (hake, megrim, angler fish and Norway lobster) as well as the results of the biological samplings for hake lengths made at the two Galician ports, and the percentages estimated for each age group in the catch,Les auteurs de ce travail ant fait une étude en détaille de la flottille espagnole a la pécherie demersale a la Grande Sol e et a la côte de l'Irlande et inmatriculée aux ports de Vigo, La Coruña, Ondárroa et Pasajes. Des données sur les lieux de peche, les prises, l'effort le rendement et la distribution saisonniére des plus importantes espéces (merlu, cardine, baudroie et langoustine) sont exposées, aussi que les résultats des échantillonnages biologiques des tailles du merlu réalisés aux deux ports galiciens, et les pourcentages pour chaque groupe d'age cornpris dans les captures.Versión del editor

A new thresholding approach for automatic generation of polygonal approximations

The present paper proposes a new algorithm for automatic generation of polygonal approximations of 2D closed contours based on a new thresholding method. The new proposal computes the signi cance level of the contour points using a new symmetric version of the well-known Ramer, Douglas - Peucker method, and then a new Adaptive method is applied to threshold the normalized signi cance level of the contour points to generate the polygonal approximation. The experiments have shown that the new algorithm has good performance for generating polygonal approximations of 2D closed contours. Futhermore, the new algorithm does not require any parameter to be tuned

La pesquería demersal gallega. Estrategias de pesca para su regulación racional en base a la merluza

El presente trabajo consta de dos partes diferenciadas. En la primera se hace una descripción de la pesquería demersal gallega a través del análisis de las flotas distribuidas por puertos y artes de pesca, así como de sus caladeros y las especies en ellos existentes. En la segunda, entramos en la dinámica de la especie más importante económicamente, que es la merluza (Merluccius merluccius L.) . Para ello se hace, en primer lugar, un cálculo de los vectores de mortalidad por pesca a que está sometida, mediante los modelos de Análisis de Cohortes con Distribuciones de Tallas (Jones. 1974) y Análisis de Cohortes (Pope. 1972), con el cual obtenemos también una estimación del reclutamiento medio. En segundo lugar y a partir de esos vectores de mortalidad por pesca actuales, subdivididos por arte de pesca, se realizaron simulaciones de cambios de malla y esfuerzo para el arrastre, y de esfuerzo para los otros artes (palangre, volanta y beta), para ver los efectos que causarían estos posibles cambios en la estrategia de pesca, en los rendimientos a largo plazo que se obtendrían. Para ello se utilizaron los modelos de Efectos de Cambios de Malla y Esfuerzo (Jones, 1974) y el modelo Multiartes (Ricker, 1975). Las pérdidas inmediatas por cambio de malla se calcularon mediante el modelo efectos de cambios en las mallas (Gulland, 1961), que nos da, asimismo, los efectos a largo plazo para el arrastre. Se realizan también estudios de sensibilidad del modelo de Ricker, y se calcula la correlación de los resultados obtenidos con los modelos empleados.The present paper has two different parts. Firstly we show a descrintíon of the demersal fishery of Galicia (NW Spain), thruough the analysis of their fleets distributed by fishing ports, gears, and also the fishing grounds and the species living on them. Secondly we study the population dynamics of the more important commercial species, that it is the Hake (Merluccius merluccius L.). To do so, we firstly do a calculation of the fishing mortality vectors exerted on this species, using the Cohort Analysis with Length Compositions (Jones, 1974), and the Cohort Analysis Model (Pope, 1972). In this way, we obtain also a estimation of the mean recruitment. Secondly, and with these current fishing mortality vectors subdivided by fishing gear, we did mesh size and effort level simulations for the trawlers, and only in the effort for the other gears (long-line, gillnet, and small gillnet), with the aim of studing the long-term changes in the yield of hake in this fishery with these simulations. To do so, we used the models of changes in mesh size and fishing effort (Jones, 1974), and multigears (Ricker, 1975). The immediate looses caused by the mesh size changes were calculated by the Gulland model (1961), that gave us also the long-term effects for the trawling. We also study the sensibility of the Ricker Model, and we calculate the correlation between the results obtained with the differents models used.Dans cet travail il-y-a deux parties différentes. La premier cet une description de la pécherie demersal galicienne a partir de l'analyse des flotilles distribues par ports et engins de peche, de meme que de la zone de peche et des especes qué on truve la. Rans la deuxiéme partie, nous parlons de la dynamique de la population de I'espece plus important économiauement, cet a dire, la merlu. Nous calculons, premierement, les vecteures de mortalité par peche avec les modeles de Analysis de Cohortes avec Distribution de Tailles (Jones, 1974), et Analysis de Cohortes (Pope,1972), de façon que nous obtenons aussi une estimationdu recrutement moyen. Apres, a partir de cettes vecteures de mortalité par peche actueles par engin de peche, on a fait des simulations de change de ouverture de maille et effort pour le chault, et de l'effort pour les outres envins (palangre, filets maillants et petits filets maillants), pour voir les consecances que rapporten cettes posibles chanaes du sistema de néche aux rendiments au long terme. Cet pour ca que nous avons utilise les modeles de Effects des Changes de Maílle et Effort (Jones, 1974), et le modele Multiengins (Ricker. 1975). La perte inmédiat pour varíation de la ouverture de la maille fut calcúle avec le modele de Gulland (1961) que nous donne au meme temps les consecances au long ternos pour le chalut. On fait aussi études de sensibilité du modele de Ricker, et on fait le calcule de la corrélation des resultats obtenus avec les modeles emuloyes.Versión del editor0,000

Different resource allocation strategies result from selection for litter size at weaning in rabbit does

This study examined the effect of long-term selection of a maternal rabbit line, solely for a reproductive criterion, on the ability of female rabbits to deal with constrained environmental conditions. Female rabbits from generations 16 and 36 (n = 72 and 79, respectively) of a line founded and selected to increase litter size at weaning were compared simultaneously. Female rabbits were subjected to normal (NC), nutritional (NF) or heat (HC) challenging conditions from 1st to 3rd parturition. Animals in NC and NF were housed at normal room temperatures (18°C to 25°C) and respectively fed with control (11.6 MJ digestible energy (DE)/kg dry matter (DM), 126 g digestible protein (DP)/kg DM, and 168 g of ADF/kg DM) or low-energy fibrous diets (9.1 MJ DE/kg DM, 104 g DP/kg DM and 266 g ADF/kg DM), whereas those housed in HC were subjected to high room temperatures (25°C to 35°C) and the control diet. The litter size was lower for female rabbits housed in both NF and HC environments, but the extent and timing where this reduction took place differed between generations. In challenging conditions (NF and HC), the average reduction in the reproductive performance of female rabbits from generation 16, compared with NC, was &#8722;2.26 (P<0.05) and &#8722;0.51 kits born alive at 2nd and 3rd parturition, respectively. However, under these challenging conditions, the reproductive performance of female rabbits from generation 36 was less affected at 2nd parturition (&#8722;1.25 kits born alive), but showed a greater reduction at the 3rd parturition (&#8722;3.53 kits born alive; P<0.05) compared with NC. The results also showed differences between generations in digestible energy intake, milk yield and accretion, and use of body reserves throughout lactation in NC, HC and NF, which together indicate that there were different resource allocation strategies in the animals from the different generations. Selection to increase litter size at weaning led to increased reproductive robustness at the onset of an environmental constraint, but failure to sustain the reproductive liability when the challenge was maintained in the long term. This response could be directly related to the shortterm environmental fluctuations (less severe) that frequently occur in the environment where this line has been selected.The authors thank Professor Enrique Blas Ferrer for his valuable comments on the initial version of this document, Juan Carlos Moreno for his help in conducting the trial at the experimental farm, and the Ministry of Economy and Competitiveness (Project: AGL2011-30170-C02-01) for economic support.Savietto, D.; Cervera Fras, MC.; Ródenas Martínez, L.; Martínez Paredes, EM.; Baselga Izquierdo, M.; García Diego, FJ.; Larsen, T.... (2014). Different resource allocation strategies result from selection for litter size at weaning in rabbit does. Animal. 8(4):618-628. https://doi.org/10.1017/S1751731113002437S61862884García-Diego, F.-J., Pascual, J. J., & Marco, F. (2011). Technical Note: Design of a large variable temperature chamber for heat stress studies in rabbits. World Rabbit Science, 19(4). doi:10.4995/wrs.2011.938Ragab, M., & Baselga, M. (2011). A comparison of reproductive traits of four maternal lines of rabbits selected for litter size at weaning and founded on different criteria. Livestock Science, 136(2-3), 201-206. doi:10.1016/j.livsci.2010.09.009Friggens, N. C. (2003). Body lipid reserves and the reproductive cycle: towards a better understanding. Livestock Production Science, 83(2-3), 219-236. doi:10.1016/s0301-6226(03)00111-8Littell, R. C., Henry, P. R., & Ammerman, C. B. (1998). Statistical analysis of repeated measures data using SAS procedures. Journal of Animal Science, 76(4), 1216. doi:10.2527/1998.7641216xEstany, J., Baselga, M., Blasco, A., & Camacho, J. (1989). Mixed model methodology for the estimation of genetic response to selection in litter size of rabbits. Livestock Production Science, 21(1), 67-75. doi:10.1016/0301-6226(89)90021-3Fernández-Carmona, J., Alqedra, I., Cervera, C., Moya, J., & Pascual, J. J. (2003). Effect of lucerne-based diets on performance of reproductive rabbit does at two temperatures. Animal Science, 76(2), 283-295. doi:10.1017/s1357729800053534Fernández-Carmona, J., Cervera, C., Sabater, C., & Blas, E. (1995). Effect of diet composition on the production of rabbit breeding does housed in a traditional building and at 30°C. Animal Feed Science and Technology, 52(3-4), 289-297. doi:10.1016/0377-8401(94)00715-lHarano, Y., Ohtsuki, M., Ida, M., Kojima, H., Harada, M., Okanishi, T., … Shigeta, Y. (1985). Direct automated assay method for serum or urine levels of ketone bodies. Clinica Chimica Acta, 151(2), 177-183. doi:10.1016/0009-8981(85)90321-3Dauncey, M. J. (1990). Thyroid hormones and thermogenesis. Proceedings of the Nutrition Society, 49(2), 203-215. doi:10.1079/pns19900024Savietto, D., Blas, E., Cervera, C., Baselga, M., Friggens, N. C., Larsen, T., & Pascual, J. J. (2012). Digestive efficiency in rabbit does according to environment and genetic type. World Rabbit Science, 20(3). doi:10.4995/wrs.2012.1152Falconer, D. S. (1990). Selection in different environments: effects on environmental sensitivity (reaction norm) and on mean performance. Genetical Research, 56(1), 57-70. doi:10.1017/s0016672300028883Vicente, J., & García-Ximénez, F. (1993). Effects of strain and embryo transfer model (embryos from one versus two donor does/recipient) on results of cryopreservation in rabbit. Reproduction Nutrition Development, 33(1), 5-13. doi:10.1051/rnd:19930101Quiniou, N., Renaudeau, D., Dubois, S., & Noblet, J. (2000). Influence of high ambient temperatures on food intake and feeding behaviour of multiparous lactating sows. Animal Science, 70(3), 471-479. doi:10.1017/s1357729800051821Theilgaard, P., Sánchez, J. P., Pascual, J. J., Friggens, N. C., & Baselga, M. (2006). Effect of body fatness and selection for prolificacy on survival of rabbit does assessed using a cryopreserved control population. Livestock Science, 103(1-2), 65-73. doi:10.1016/j.livsci.2006.01.007Brecchia, G., Bonanno, A., Galeati, G., Federici, C., Maranesi, M., Gobbetti, A., … Boiti, C. (2006). Hormonal and metabolic adaptation to fasting: Effects on the hypothalamic–pituitary–ovarian axis and reproductive performance of rabbit does. Domestic Animal Endocrinology, 31(2), 105-122. doi:10.1016/j.domaniend.2005.09.006Piles, M., Garreau, H., Rafel, O., Larzul, C., Ramon, J., & Ducrocq, V. (2006). Survival analysis in two lines of rabbits selected for reproductive traits1. Journal of Animal Science, 84(7), 1658-1665. doi:10.2527/jas.2005-678Sanchez, J. P., Baselga, M., & Ducrocq, V. (2006). Genetic and environmental correlations between longevity and litter size in rabbits. Journal of Animal Breeding and Genetics, 123(3), 180-185. doi:10.1111/j.1439-0388.2006.00590.xQuevedo, F., Cervera, C., Blas, E., Baselga, M., & Pascual, J. J. (2006). 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Genetics of litter size in three maternal lines of rabbits: Repeatability versus multiple-trait models. Journal of Animal Science, 84(9), 2309-2315. doi:10.2527/jas.2005-622Garcı́a, M. L., & Baselga, M. (2002). Estimation of genetic response to selection in litter size of rabbits using a cryopreserved control population. Livestock Production Science, 74(1), 45-53. doi:10.1016/s0301-6226(01)00280-9Cervera, C., & Carmona, J. F. (s. f.). Nutrition and the climatic environment. Nutrition of the rabbit, 267-284. doi:10.1079/9781845936693.0267Nicodemus, N., Redondo, R., Pérez-Alba, L., Carabaño, R., De Blas, J. C., & García, J. (2010). Effect of level of fibre and type of grinding on the performance of rabbit does and their litters during the first three lactations. Livestock Science, 129(1-3), 186-193. doi:10.1016/j.livsci.2010.01.023Theilgaard, P., Sánchez, J., Pascual, J., Berg, P., Friggens, N. C., & Baselga, M. (2007). Late reproductive senescence in a rabbit line hyper selected for reproductive longevity, and its association with body reserves. Genetics Selection Evolution, 39(2), 207. doi:10.1186/1297-9686-39-2-207Martínez-Paredes, E., Ródenas, L., Martínez-Vallespín, B., Cervera, C., Blas, E., Brecchia, G., … Pascual, J. J. (2012). Effects of feeding programme on the performance and energy balance of nulliparous rabbit does. animal, 6(7), 1086-1095. doi:10.1017/s1751731111002643Baselga M 2004. Genetic improvement of meat rabbits. Programmes and diffusion. In Proceedings of 8th World Rabbit Science Congress, 5–7 September 2004, Puebla, Mexico, pp. 1–13