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184 Pags. Tesis dirigida por Miguel Hycka, investigador científico de la EEAD-CSIC., [ES] La presente tesis pretende contribuir al conocimiento de la mielga, mediante el estudio de su habitat, número cromosómico, diferenlciación morfológica, fisiológica y agronómica con respecto a las alfalfas cultivadas de crecimiento erecto, variabilidad intra e interpoblacinal e interés agronómico y como banco de germoplasma para mejora genética. El estudio se ha efectuado sobre las mielgas que crecen en la Cuenca Media del Ebro., [EN] The present thesis tries to contribute to the knowledge of this forage species, studying its habitat, chromosomic number, morphological, physiological, and agronomical differences, intra and interpopulation variability, agronomical interest and germplasm for breeding, am these in comparison with the upright growing lucernes. This study has been carried out on mielgas growing in the Middle Ebro Va11ey

A global analysis of several productive indicators and the postpartum anoestrous interval (PPI) of 549 beef cowswas carried out to determine the management factors related with postpartum ovarian reactivation in extensive mountainfarming systems. Multivariate statistic methods (Multiple Correspondence Analysis and Cluster Analysis) were usedto analyse the data due to the multifactorial nature of the processes involved. PPI was associated to four factors thatexplained 59% of the total inertia of the sample and were defined as follows: «Prepartum feeding level» (19% of theinertia), «Postpartum feeding level-Parity» (16.4%), «Suckling frequency» (13%) and «Calving difficulty» (10.5%).These factors were introduced into a Cluster Analysis that identified five types of cows: «Primiparous cows», «Twicedailysuckling», «Ad libitum suckling-Brown Swiss», «Autumn calving season» and «Spring calving season». Cowbreed was not related to PPI, although the Cluster Analysis associated the suckling-induced prolonged PPI with BrownSwiss animals. In Brown Swiss breed, PPI was longer in the spring than in the autumn due to nutritional differencesrather than to a seasonal effect. Autumn calving was better adapted to dry mountain conditions., Para determinar los factores de explotación relacionados con la reactivación ovárica postparto en vacas nodrizas se realizó un análisis global de la serie de indicadores productivos y la duración del anestro postparto (APP) de 549 vacas explotadas en condiciones extensivas. Debido a la naturaleza multifactorial del proceso en estudio se eligió la metodología estadística multivariante (Análisis Factorial de Correspondencias Múltiples y Análisis Cluster). La duración del APP estuvo asociada a cuatro factores que explicaron el 59% de la heterogeneidad inicial de la muestra y que se definieron como : "Alimentación preparto" (19% de la inercia), "Alimentación postparto-Edad" (16.4% ), "Manejo del ternero" (13% ) y "Dificultad al parto" (10.5% ). Estos factores se introdujeron en un Análisis Cluster que identificó cinco grupos de vacas con características productivas y reproductivas diferentes, y que denominamos como "Primíaras", "Acceso restringido", "Acceso Libre-Parda de Montaña", "Parto de otoño" y "Parto de primavera" (...)

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Carcasses of Churro Galego Bragançano purebred and Suffolk and Merino Precoce crossbred lambs reared under three different conventional production system of northeast of Portugal were evaluated. Carcasses of male lambs had larger muscle longissimus width (P < 0.05) and smaller subcutaneous fat thickness (P < 0.05) than the female lambs. Carcasses of crossbred lambs had higher (P < 0.05) compactness indices and leg and shoulder proportion than Bragançano purebred. Suffolk crossed had lower KKCF proportion (P < 0.05) than Bragançano and Merino crossbred lambs. Male lambs had higher (P < 0.05) muscle proportion in almost all carcass joints than the female lambs. It was concluded that Suffolk can be used as sire breed in Bragançano ewes to produce lambs with leaner and more compact carcasses and better fat distribution, which allows slaughtering at higher slaughter weight, specially in more intensive production systems. Female lambs should be slaughtered at lower carcass weight than male lambs in order to produce carcasses with the same fattening degree. Se evaluaron canales de corderos Churra Galega Bragançana y se cruzaron con Suffolk y Merino Precoz criados en tres sistemas de producción en el nordeste de Portugal. Los corderos machos presentaron el músculo longissimus más ancho (P < 0.05) y con menor (P < 0.05) espesor de grasa subcutánea que las hembras. Los corderos cruzados tuvieron mayores (P < 0.05) índices de compacidad y de proporciones de pierna y espalda que los Bragançanos. Los corderos cruzados Suffolk tuvieron menor proporción de grasa perirrenal que los Bragançanos y cruzados Merino. Los corderos machos tuvieron mayores (P < 0.05) proporciones de músculo, en casi todos los cortes, que las hembras. Se concluye que se pueden utilizar sementales Suffolk sobre ovejas Bragançanas para producir corderos con canales más magras, más compactas y con mejor distribución de la grasa, permitiendo sacrificios a pesos más elevados, especialmente en los sistemas de producción más intensivos. Las hembras deben ser sacrificadas con pesos más bajos para producir canales con el mismo estado de engrasamiento que los machos.

The aim of this study was to disseminate knowledge regarding the perceptions of Spanish consumers of chicken breast and their related lifestyles and to classify different consumer groups according to their food-related lifestyles. Nearly all Spanish consumers consume chicken breast once or twice per week. The preference for white or yellow chicken appears to be divided evenly, although the preferred is white chicken. Chicken breast is perceived as a product of convenience. Seventy percent of consumers buy chicken breast because it is easy to cook whereas only 27% prefer to buy the entire chicken. Four groups of consumers based on their lifestyles and their perceptions of chicken breast were identified: "Urban single", "Traditional", "Innovative precariat" and "Gourmet". These types of consumers are consistent with types other studies have identified in terms of the lifestyles associated with other foods. Defining groups of consumers with differentiated perceptions of chicken breast is useful in managing marketing strategies to satisfy the various consumption needs associated with chicken breast. Published

The aim of this study was to analyse three commercial beef categories of the ‘Serrana de Teruel breed’ to define the appropriate commercial option. Twenty ‘Serrana de Teruel’ male calves at 9 months were assigned to the commercial beef categories (young bulls, bulls and steers), slaughtered at 12, 22 and 22 months of age, respectively. The in vivo ultrasound backfat thickness was greater than the dorsal fat thickness, and the young bulls and steers had a similar fat thickness, that was greater than the bulls in both areas. The slaughter weight and cold carcass weight were significantly different between the commercial categories. However, the differences were not sufficient to modify the dressing percentage, carcass conformation and fatness degree between the young bulls and bulls. The maximum stress of the muscle at 7 d of ageing was lower in the steers than in the young bulls and bulls. In general, the lightness of the meat in the bulls was lower than that in the young bulls and steers. The subcutaneous fat of the bull carcasses had a vivid colour and stored more carotenoids than that of the young bulls and steers. Hence, bulls produced heavier and better conformed carcasses with more edible meat and less fat than the other categories. However, steers are recommended to produce large carcasses with more trim and cover fat than the other categories. Finally, it seems that bulls are the most suitable commercial category to ‘Serrana de Teruel’ breed. Ministry of Science and Innovation of Spain, the European Union Regional Development Funds and Government of Aragon (FITE 2013-351A). Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (PET2007-05-C03-01). J. Álvarez-Rodríguez was in receipt of a grant from INIA-DGA.

1 página.-- Comunicación presentada en: Resúmenes del XII Congreso Ibérico de Parasitoloñgía (CIP XII) (Zaragoza, 5-8 de julio de 2011)., Las helminthosis digestivas causan graves pérdidas en las explotaciones ganaderas de pequeños rumiantes...., Proyectos RTA 2006-00183-C03-01 a RTA 2010-00094-CO3-01 a 03. Trabajo desarrollado dentro del proyecto RTA 2006-00183-C3-00

The World Organisation for Animal Health (OIE) requested an International Standard anti-Brucella melitensis Serum (ISaBmS) to standardise diagnostic tests and reagents for sheep and goats. The agreed criteria were the highest dilution (in negative serum) of the standard which must give a positive result and the lowest dilution (in negative serum) which must simultaneously give a negative result. The two dilutions for each assay were, respectively: indirect enzyme-linked immunosorbent assay (iELISA) 1/64 and 1/750, competitive ELISA (cELISA) 1/8 and 1/300, fluorescent polarisation assay (FPA) 1/16 and 1/200, Rose Bengal test (RBT) 1/16 and 1/200. The OIE International Standard Serum (OIEISS) will remain the primary standard for the RBT; the ISaBmS is an additional standard. It was impossible to set criteria for the complement fixation test, therefore the OIEISS will remain the primary standard. The ISaBmS can be used to standardise iELISA, cELISA and FPA to diagnose sheep and goat brucellosis. This standard should facilitate harmonisation of tests used for brucellosis surveillance and international trade in these species. L’Organisation mondiale de la santé animale (OIE) a recommandé la mise au point d’un sérum international de référence anti-Brucella melitensis (ISaBmS) afin de standardiser les épreuves diagnostiques et les réactifs utilisés chez les ovins et caprins. Les critères sélectionnés ont été la dilution la plus élevée (d’un sérum négatif) avec laquelle on observe une réaction positive et la dilution la moins élevée (d’un sérum négatif) avec laquelle on observe simultanément une réaction négative. Les deux dilutions pour chaque épreuve ont été respectivement les suivantes : pour l’épreuve immuno-enzymatique indirecte (ELISAi), 1/64 et 1/750 ; pour l’ELISA de compétition (ELISAc), 1/8 et 1/300 ; pour l’épreuve de polarisation en fluorescence (EPF), 1/16 et 1/200 ; pour l’épreuve à l’antigène tamponné (EAT) ou rose Bengale, 1/16 et 1/200. Le sérum de référence international de l’OIE (OIEISS) doit continuer à être utilisé comme étalon primaire pour l’EAT, l’ISaBmS constituant un sérum de référence additionnel. Concernant l’épreuve de fixation du complément, il n’a pas été possible de définir des critères satisfaisants, de sorte que l’OIEISS reste l’étalon primaire. L’ISaBmS peut être utilisé pour standardiser les épreuves ELISAi, ELISAc et EAT pour le diagnostic de la brucellose ovine et caprine. Ce sérum de référence devrait faciliter l’harmonisation des épreuves utilisées pour la surveillance de la brucellose ou dans le cadre du commerce international de ces espèces. La Organización Mundial de Sanidad Animal (OIE) pidió un suero de referencia internacional anti-Brucella melitensis (ISaBmS) con el fin de estandarizar los reactivos y las pruebas de diagnóstico para ovinos y caprinos. Los criterios acordados fueron: la dilución más alta (en suero negativo) del suero de referencia que debe dar resultado positivo y la dilución más baja (en suero negativo) que debe dar simultáneamente resultado negativo. En las distintas pruebas, esas diluciones fueron, respectivamente, las siguientes: ensayo inmunoenzimático indirecto (ELISAi), 1/64 y 1/750; ELISA de competición (ELISAc), 1/8 y 1/300; ensayo de fluorescencia polarizada (FP), 1/16 y 1/200; y prueba de rosa de Bengala (RB), 1/16 y 1/200. El suero de referencia internacional de la OIE (OIEISS) seguirá siendo la referencia básica para la prueba RB, y el ISaBmS será en este caso una referencia complementaria. Resultó imposible definir criterios para la prueba de fijación del complemento, por lo que el OIEISS seguirá siendo el principal suero de referencia. Cabe utilizar el ISaBmS para estandarizar las pruebas ELISAi, ELISAc y FP de diagnóstico de la brucelosis en ovinos y caprinos. Este suero de referencia debería facilitar la armonización de las pruebas empleadas en la vigilancia de la brucelosis y en el comercio internacional de dichas especies.

Sheep farming systems in Spain are experiencing an intensification process, characterised by a general selection criteria of enhancing prolificacy in ewes, and by increasing indoor feeding with concentrates to the detriment of grazing. This study evaluated the effects of concentrate supplementation and prolificacy on productive and economic performance of a local sheep breed in different price scenarios. Ewes were fed forage hay ad libitum, without (in pre-partum period, PRE-HAY; and in post-partum period, POST-HAY) or with concentrates (300 g/d in pre-partum period, PRE-CON; and 750 g/d in post-partum period, POST-CON). The inclusion of concentrate during the pre-partum period (last 10 weeks of pregnancy) had no effect on the productive performance of the ewes. In contrast, the inclusion of concentrate in the post-partum period (6 weeks), resulted in greater milk yield (1009 vs. 1275 ± 89 g/d), lamb average daily gain (151±12 vs. 225±19 g/d) and lamb output (kg of lamb LW weaned). However, the greater productivity thanks to the use of concentrates did not always turn into greatest profitability, since the economic margin was highly influenced by the cost of the diet and extremely subjected to variability in price of concentrates. Hence, the inclusion of concentrates in sheep meat production was not always justified in economic terms. In conclusion, the use of concentrates should only be considered as long as prices of commodities remain low, and inadvisable when prices reach a certain threshold or are subject to certain volatility in markets. This study was supported by the Ministry of Science and Innovation of Spain and the European Union Regional Development Funds (INIA PET2007-06-C03-01; RZP2009-005) and the Research Group Funds of the Aragon Government (A49 and A11).

The objective of this study was to compare the ability of Basis spline (B-spline) models and five non-linear functions (Richards, Brody, Von Bertalanffy, Gompertz and Logistic) to describe the growth of females of a beef cattle breed and predict cow mature weight (A). Random regression models that included animal variation within function parameters were fitted using mixed model procedures. Comparisons were made among these functions for goodness of fit, standardised residuals and biological interpretability of the growth curve parameters. The B-spline function showed the best goodness of fit and within non-linear functions, the Richards and Von Bertalanffy functions estimated bodyweight at different periods accurately. The method of fitting the residual variance that provided the best goodness of fit in the model was the constant plus power variance function. The Richards function was found to be the best non-linear function and was compared with the B-spline function to predict mature weight. When the A parameter was estimated using fixed effects, it had a low correlation with the actual mature weight of the cow and the use of this estimate yielded no more gain in predictive accuracy of mature weight than the use of average breed mature weight. When A was estimated using fixed and random effects, it had a moderate correlation with actual mature weight for the B-spline and Richards functions. The use of both types of effects to estimate the maturity index reduced the error compared with the use of average mature weight, especially for the B-spline function, which is recommended as the best function to describe animal growth and predict mature weight. The authors recognise the CITA farm staff working at La Garcipollera and Zaragoza Research Stations for their technical support. This research was funded by INIA (RZP2009–005, RTA2010–057) and the European Regional Development Fund.

The effect of the ageing method (bone-in or boneless), ageing period (7 or 14 days), cooking method (grilling or water bath preparation) and sample thickness (1, 2 or 4 cm) on the meat texture characteristics of the longissimus thoracis muscle of six young, commercial bulls was measured using a texture analyser incorporating compression and Warner-Bratzler devices. The sarcomere length of the raw meat and cooking losses were also recorded. The ageing method and ageing period had more influence on the textural properties studied than either the cooking method or sample thickness. Cooking losses were, however, mainly influenced by the cooking method. Although the cooking method had no significant effect on meat toughness, the meat tended to be tougher when grilled than when prepared in a water bath. Meat tenderness mainly improved during the first week of storage. Se ha estudiado el efecto del método de maduración (con o sin hueso), el tiempo de maduración (7 ó 14 días), el método de cocinado (grill o baño de agua) y el espesor de la muestra (1, 2 ó 4 cm) sobre la textura del Longissimus thoracis de 6 añojos de tipo comercial. El ensayo se llevó a cabo utilizando dos células distintas (compresión y Warner- Bratzler). Asimismo se midieron la longitud de los sarcómeros de la carne cruda y las pérdidas por cocinado. El método y el tiempo de maduración fueron más importantes que el método de cocinado o el espesor de la muestra en las características de textura. El método de cocinado afectó principalmente a las pérdidas por cocinado. Aunque el método de cocinado no afectó significativamente a la dureza, la carne tendió a ser más dura al grill que un baño de agua. La dureza de la carne disminuyó con la maduración, especialmente en la primera semana.

Background Alterations in lipid metabolism occur when animals are exposed to different feeding systems. In the last few decades, the characterisation of genes involved in fat metabolism and technological advances have enabled the study of the effect of diet on the milk fatty acid (FA) profile in the mammary gland and aided in the elucidation of the mechanisms of the response to diet. The aim of this study was to evaluate the effect of different forage diets (grazing vs. hay) near the time of ewe parturition on the relationship between the fatty acid profile and gene expression in the mammary gland of the Churra Tensina sheep breed. Results In this study, the forage type affected the C18:2 cis-9 trans-11 (CLA) and long-chain saturated fatty acid (LCFA) content, with higher percentages during grazing than during hay feeding. This may suggest that these FAs act as regulatory factors for the transcriptional control of the carnitine palmitoyltransferase 1B (CPT1B) gene, which was more highly expressed in the grazing group (GRE). The most highly expressed gene in the mammary gland at the fifth week of lactation is CAAT/ enhancer- binding protein beta (CEBPB), possibly due to its role in milk fat synthesis in the mammary gland. More stable housekeeping genes in the ovine mammary gland that would be appropriate for use in gene expression studies were ribosomal protein L19 (RPL19) and glyceraldehyde- 3- phosphate dehydrogenase (GAPDH). Conclusions Small changes in diet, such as the forage preservation (grazing vs. hay), can affect the milk fatty acid profile and the expression of the CPT1B gene, which is associated with the oxidation of fatty acids. When compared to hay fed indoors, grazing fresh low mountain pastures stimulates the milk content of CLA and LCFA via mammary uptake. In this sense, LCFA in milk may be acting as a regulatory factor for transcriptional control of the CPT1B gene, which was more highly expressed in the grazing group.

Background Climatic factors play an important role in determining species distributions and phenotypic variation of populations over geographic space. Since domestic sheep is managed under low intensive systems animals could have retained some genome adaptive footprints. The gene encoding the Hsp90α has been extensively studied in sheep and some polymorphisms located at its promoter have been associates with differences in the transcription rate of the gene depending on climatic conditions. In this work the relationships among the distribution and frequencies of 11 polymorphisms of the ovine HSP90AA1 gene promoter in 31 sheep breeds and the climatic and geographic variables prevailing in their regions of origin have been studied. Also the promoter sequence has been characterized in 9 species of the Caprinae subfamily. Results Correlations among several climatic variables and allele frequencies of the polymorphisms of the HSP90AA1 gene promoter linked with differences in the transcription activity of the gene under heat stress conditions have been assessed. A group of breeds reared in semi dry climates have high frequencies of the insertion allele of the g.667-668insC associated with the heat stress response. Other group of breeds native to semi arid conditions showed very low frequencies of this same allele. However, in some cases, this previous correlation has not been achieved, revealing the high levels of gene flow among populations occurred following domestication. The Bayesian Test of Beaumont and Balding identified two outlier loci, the g.522A > G and g.703_704del(2)A candidates to balancing and directional selection, respectively. Polymorphisms detected in O. aries are also present in several species of the Caprinae subfamily being C. hircus, O. musimon and O. moschatus those sharing the highest number of them with O. aries. Conclusions Despite domestication, sheep breeds showed some genetic footprints related to climatic variables. Adaptation of breeds to heat climates can suppose a selective advantage to cope with global warming caused by climatic change. Polymorphisms of the HSP90AA1 gene detected in the Ovis aries species are also present in wild species from the Caprinae subfamily, indicating a great antiquity of these mutations and its importance in the adaptation of species to past climatic conditions existing in its native environments. Electronic supplementary material The online version of this article (doi:10.1186/s12862-015-0280-x) contains supplementary material, which is available to authorized users.

Background: Biting midges of the genus Culicoides (Diptera: Ceratopogonidae) are biological vectors of internationally important arboviruses. To understand the role of Culicoides in the transmission of these viruses, it is essential to correctly identify the species involved. Within the western Palaearctic region, the main suspected vector species, C. obsoletus, C. scoticus, C. dewulfi and C. chiopterus, have similar wing patterns, which makes it difficult to separate and identify them correctly. Methods: In this study, designed as an inter-laboratory ring trial with twelve partners from Europe and North Africa, we assess four PCR-based assays which are used routinely to differentiate the four species of Culicoides listed above. The assays based on mitochondrial or ribosomal DNA or microarray hybridisation were tested using aliquots of Culicoides DNA (extracted using commercial kits), crude lysates of ground specimens and whole Culicoides (265 individuals), and non-Culicoides Ceratopogonidae (13 individuals) collected from across Europe. Results: A total of 800 molecular assays were implemented. The in-house assays functioned effectively, although specificity and sensitivity varied according to the molecular marker and DNA extraction method used. The Obsoletus group specificity was overall high (95-99%) while the sensitivity varied greatly (59.6-100%). DNA extraction methods impacted the sensitivity of the assays as well as the type of sample used as template for the DNA extraction. Conclusions: The results are discussed in terms of current use of species diagnostic assays and the future development of molecular tools for the rapid differentiation of cryptic Culicoides species. Published

Background Reference genes with stable expression are required to normalize expression differences of target genes in qPCR experiments. Several procedures and companion software have been proposed to find the most stable genes. Model based procedures are attractive because they provide a solid statistical framework. NormFinder, a widely used software, uses a model based method. The pairwise comparison procedure implemented in GeNorm is a simpler procedure but one of the most extensively used. In the present work a statistical approach based in Maximum Likelihood estimation under mixed models was tested and compared with NormFinder and geNorm softwares. Sixteen candidate genes were tested in whole blood samples from control and heat stressed sheep. Results A model including gene and treatment as fixed effects, sample (animal), gene by treatment, gene by sample and treatment by sample interactions as random effects with heteroskedastic residual variance in gene by treatment levels was selected using goodness of fit and predictive ability criteria among a variety of models. Mean Square Error obtained under the selected model was used as indicator of gene expression stability. Genes top and bottom ranked by the three approaches were similar; however, notable differences for the best pair of genes selected for each method and the remaining genes of the rankings were shown. Differences among the expression values of normalized targets for each statistical approach were also found. Conclusions Optimal statistical properties of Maximum Likelihood estimation joined to mixed model flexibility allow for more accurate estimation of expression stability of genes under many different situations. Accurate selection of reference genes has a direct impact over the normalized expression values of a given target gene. This may be critical when the aim of the study is to compare expression rate differences among samples under different environmental conditions, tissues, cell types or genotypes. To select reference genes not only statistical but also functional and biological criteria should be considered. Under the method here proposed SDHA/MDH1 have arisen as the best set of reference genes to be used in qPCR assays to study heat shock in ovine blood samples.