Person:
Alfonso Ruiz, Leopoldo

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Alfonso Ruiz

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Leopoldo

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Agronomía, Biotecnología y Alimentación

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IS-FOOD. Research Institute on Innovation & Sustainable Development in Food Chain

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0000-0002-5662-9997

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1974

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Search Results

Now showing 1 - 10 of 19
  • PublicationOpen Access
    Quality characteristics of Huacaya alpaca fibre produced in the Peruvian Andean Plateau region of Huancavelica
    (Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria (INIA), 2008) Montes Andueza, María; Quicaño, I.; Quispe, R.; Quispe Peña, Edgar; Alfonso Ruiz, Leopoldo; Producción Agraria; Nekazaritza Ekoizpena
    Se describe la calidad de la fibra de alpacas Huacaya producida en la región de Huancavelica (Perú), utilizando una muestra de 203 alpacas pertenecientes a ocho comunidades de alpaqueros ubicadas entre 4.100 y 4.750 m de altitud. El diámetro medio de la fibra, 22,7 μm (SE 0,2), fue inferior a los valores referidos para la raza Huacaya en otras zonas, variando con el sexo, la edad y la comunidad de origen (P < 0,01). Los machos mostraron tener una fibra más fina que las hembras, en contraste con los resultados de otros estudios, aunque puede deberse a que proceden de rebaños seleccionados de Puno y Cusco. No se detectó relación lineal entre el diámetro de la fibra y la longitud de mecha. Antes de iniciar un futuro programa de mejora de la producción de fibra en esa región, se deberían realizar más estudios para conocer mejor los caracteres de producción de fibra y cuantificar su importancia económica. Aunque puede parecer difícil realizar este tipo de investigaciones en la zona alto andina peruana, se vio que es posible si alpaqueros y promotores de desarrollo participan activamente en ellas.
  • PublicationOpen Access
    Textile characteristics of fiber from Huacaya alpacas (Vicugna pacos)
    (Universidad Nacional de Trujillo (Perú). Facultad de Ciencias Agropecuarias, 2019) Paucar Chanca, Rufino; Alfonso Ruiz, Leopoldo; Soret Lafraya, Beatriz; Mendoza Ordóñez, G.; Alvarado Quezada, F.; Agronomía, Biotecnología y Alimentación; Agronomia, Bioteknologia eta Elikadura
    Fiber from alpacas represents a substantial component of economic output for South American countries. In this study it determined the textile characteristics of fibers obtained from Huacaya alpacas raised at the South American Camelids Research and Development Center-Lachocc (CRDC-Lachocc) located at The National University of Huancavelica (UNH). Fleece samples were obtained from the mid-side rib area of 74 white alpacas (42 females and 32 males) of varying ages. The Average Fiber Diameter (AFD), Standard Deviation of the Average Fiber Diameter (SDAFD), Fiber Diameter Coefficient of Variation (FDCV), Comfort Factor (CF) and Staple Length (SL) were measured as textile characteristics and related to sex and age group. Most of the fleece samples could be classified as baby alpaca fleece according to the Peruvian Technical Standard classification (231.301.2014). Sex had no influence on any textile characteristic (p > 0.05). Meanwhile, age affected only AFD and CF (p < 0.05). Together the results indicated that alpacas farmed at CRDC-Lachocc had good potential to produce high quality fibers.
  • PublicationOpen Access
    Ayuda a las decisiones de apareamiento en poblaciones animales con información genealógica incompleta
    (Asociación Interprofesional para el Desarrollo Agrario, 2018) Alfonso Ruiz, Leopoldo; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    Los coeficientes de parentesco y de relación media de parentesco son dos herramientas útiles para determinar apareamientos con el objetivo de controlar, de forma práctica, el aumento de la consanguinidad en poblaciones animales. No obstante, su utilidad se ve condicionada por la cantidad de información genealógica disponible, pues ésta determina, en ausencia de información genómica, la precisión con que podemos estimarlos. Cuando la información genealógica sea incompleta, afectando de forma distinta a los animales, la precisión de las estimaciones de los coeficientes variará entre animales, comprometiendo el resultado de las decisiones de apareamiento. El objetivo del trabajo es calcular algunas medidas de la fiabilidad de la estimación de los coeficientes de parentesco y de relación media de parentesco. Se plantea la utilización de dos medidas basadas en la proporción de antecesores conocidos en las cinco generaciones anteriores de un animal y en la incorporación de información conocida, pero no contenida en la genealogía, a través del concepto de grupos genéticos. Los resultados muestran que estas medidas pueden ayudar a mejorar las decisiones de elección de reproductores y de acoplamiento.
  • PublicationOpen Access
    The effects of selective breeding against scrapie susceptibility on the genetic variability of the latxa black-faced sheep breed
    (EDP Sciences, 2006) Alfonso Ruiz, Leopoldo; Parada Rey, Analia; Legarra, Andrés; Ugarte, Eva; Arana Navarro, Ana; Producción Agraria; Nekazaritza Ekoizpena
    Breeding sheep populations for scrapie resistance could result in a loss of genetic variability. In this study, the effect on genetic variability of selection for increasing the ARR allele frequency was estimated in the Latxa breed. Two sources of information were used, pedigree and genetic polymorphisms (fifteen microsatellites). The results based on the genealogical information were conditioned by a low pedigree completeness level that revealed the interest of also using the information provided by the molecular markers. The overall results suggest that no great negative effect on genetic variability can be expected in the short time in the population analysed by selection of only ARR/ARR males. The estimated average relationship of ARR/ARR males with reproductive females was similar to that of all available males whatever its genotype: 0.010 vs. 0.012 for a genealogical relationship and 0.257 vs. 0.296 for molecular coancestry, respectively. However, selection of only ARR/ARR males implied important losses in founder animals (87 percent) and low frequency alleles (30 percent) in the ram population. The evaluation of mild selection strategies against scrapie susceptibility based on the use of some ARR heterozygous males was difficult because the genetic relationships estimated among animals differed when pedigree or molecular information was used, and the use of more molecular markers should be evaluated.
  • PublicationOpen Access
    Adiposity and adipogenic gene expression in four different muscles in beef cattle
    (Public Library of Science, 2017) Martínez del Pino, Lara; Arana Navarro, Ana; Alfonso Ruiz, Leopoldo; Mendizábal Aizpuru, José Antonio; Soret Lafraya, Beatriz; Producción Agraria; Nekazaritza Ekoizpena
    Anatomical site and divergent functionalities of muscles can be related to differences in IMF content, metabolism and adipogenic gene expression. Then, potential differences in different muscles in beef cattle were studied. As a second objective, the main sources of experimental variability associated to RT-qPCR results were analyzed following a nested design in order to implement appropriate experimental designs minimizing gene expression variability. To perform the study Longissimus thoracis (LT), Semitendinosus (SM), Masseter (MS), Sternomandibularis (ST) and subcutaneous adipose tissue (SAT) samples of Pirenaica young bulls (n = 4) were collected for IMF, collagen and protein quantification, analysis of adipocyte size distribution and gene expression (PPARG, CEBPA, FAPB4 and WNT10B). A greater IMF content was observed in MS and SM muscles, which had a bimodal adipocyte size distribution while it was unimodal in the muscles LT and ST. This suggest that the different IMF accretion in the muscles studied might be related to different rates of hyperplasia and hypertrophy and that IMF might develop later in LT and ST muscles. The former differences were not mirrored by the expression of the genes analyzed, which might be related to the different contribution of mature and non-mature adipocytes to the total gene expression. When comparing IMF and SAT gene expression, late and early developing tissues respectively, expression of PPARG, CEBPA and FABP4 was higher in the SAT, in agreement with bigger cell size and numbers. The variability study indicates that the analytical factors that add higher variability to the gene expression are the sampling and RT and therefore, it would be appropriate to include those replicates in the design of future experiments. Based on the results, the use of MS and SM muscles could allow less expensive experimental designs and bigger sample size that could permit the detection of lower relevant differences in gene expression.
  • PublicationOpen Access
    Adipose tissue modification through feeding strategies and their implication on adipogenesis and adipose tissue metabolism in ruminants
    (MDPI, 2020) Urrutia Vera, Olaia; Mendizábal Aizpuru, José Antonio; Alfonso Ruiz, Leopoldo; Soret Lafraya, Beatriz; Insausti Barrenetxea, Kizkitza; Arana Navarro, Ana; Agronomia, Bioteknologia eta Elikadura; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD; Agronomía, Biotecnología y Alimentación; Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa
    Dietary recommendations by health authorities have been advising of the importance of diminishing saturated fatty acids (SFA) consumption and replacing them by polyunsaturated fatty acids (PUFA), particularly omega-3. Therefore, there have been efforts to enhance food fatty acid profiles, helping them to meet human nutritional recommendations. Ruminant meat is the major dietary conjugated linoleic acid (CLA) source, but it also contains SFA at relatively high proportions, deriving from ruminal biohydrogenation of PUFA. Additionally, lipid metabolism in ruminants may differ from other species. Recent research has aimed to modify the fatty acid profile of meat, and other animal products. This review summarizes dietary strategies based on the n-3 PUFA supplementation of ruminant diets and their effects on meat fatty acid composition. Additionally, the role of n-3 PUFA in adipose tissue (AT) development and in the expression of key genes involved in adipogenesis and lipid metabolism is discussed. It has been demonstrated that linseed supplementation leads to an increase in alpha-linolenic acid (ALA) and eicosapentaenoic acid (EPA), but not in docosahexaenoic acid (DHA), whilst fish oil and algae increase DHA content. Dietary PUFA can alter AT adiposity and modulate lipid metabolism genes expression, although further research is required to clarify the underlying mechanism.
  • PublicationOpen Access
    Worldwide research trends on milk containing only A2 β-casein: a bibliometric study
    (MDPI, 2022) Jiménez Montenegro, Lucía; Alfonso Ruiz, Leopoldo; Mendizábal Aizpuru, José Antonio; Urrutia Vera, Olaia; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    The protein fraction of β-casein may play a key role in the manifestation of a new intolerance: milk protein intolerance. The most common forms of β-casein among dairy cattle breeds are A1 and A2 β-casein. During gastrointestinal digestion of A1 β-casein, an opioid called peptide β-casomorphin-7 (BCM-7) is more frequently released, which can lead to adverse health outcomes. For that reason, novel products labelled as "A2 milk"or "A1-free dairy products" have appeared on the market. In this context, a bibliometric analysis on A2 β-casein research was carried out through the Web of Science (WoS) database. The main objective of this work was to provide an overview of the state of the art in the field of β-casein A2 by analyzing the number of publications per year, trends in thematic content, the most frequently used terms, and the most important institutions and countries in the field. This bibliometric study showed that a greater effort is needed to determine the possible implications of this novel product for human health and the market.
  • PublicationOpen Access
    Impact of incorporating greenhouse gas emission intensities in selection indexes for sow productivity traits
    (Elsevier, 2019) Alfonso Ruiz, Leopoldo; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    Genetic improvement programmes should incorporate emerging challenges about environmental concerns into breeding goals. The large volume of pig meat production implies important greenhouse gas (GHG) emissions despite its lower carbon footprint per animal in front of ruminant productions. The different breeding goals considered by swine industry depending on different purebred lines, or line crosses adapted to different market demands and production constraints, could mask the effect of incorporating GHG emissions into selection indexes for improving sow productivity traits in nucleus populations. This paper analysed this effect following a methodological approach consisting in augmenting existing selection indexes derived from profit functions. An index previously described in the literature including litter size at birth, piglet perinatal survival, piglet survival to weaning, age at first conception and weaning to conception interval, was employed. This index was expanded to include GHG emissions calculating the emission intensities per litter, assuming a finished pig market and different scenarios and financial costs of GHG emissions. Results indicated that the inclusion of GHG emissions diminished the economic weight of litter size and piglet survival vs. the age at first conception and the interval weaning to conception, but did not affect significantly the contributions of these traits in the selection indexes. The improvement of sow productivity traits diluted relevantly the GHG emissions per piglet produced, and so, per kg of pork produced. The approach used in this study, despite its limitations in front of bio-economic models, has shown to be a simple and flexible way to analyse the effect of incorporating GHG emissions into existing selection indexes.
  • PublicationOpen Access
    Development of a duplex qPCR assay with locked nucleic acid probes for A, B and E kappa-casein variants detection
    (Springer Nature, 2022) Jiménez Montenegro, Lucía; Mendizábal Aizpuru, José Antonio; Alfonso Ruiz, Leopoldo; Azparren Domínguez, Leire; Urrutia Vera, Olaia; Agronomía, Biotecnología y Alimentación; Agronomia, Bioteknologia eta Elikadura; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
    Milk proteins determine important milk technological characteristics. Among caseins, Ƙ-casein has been correlated with fat and protein content and cheese yield. Fourteen Ƙ-caseins variants have been described but the alleles A, B and E are the most important ones due to their frequency and/or influence on the technological aptitudes of milk. Therefore, in the present study two different duplex qPCR assays with locked nucleic acid probes (for positions 13104 and 13124 of the Ƙ-casein gene) were developed for the detection of A, B and E variants. Firstly, DNA isolation method from milk somatic cells and hair was optimised. The developed 13124-qPCR assay showed an increased sensitivity reaching up to 6.7 copies DNA copies/reaction at a 95% confidence level with A, B and E alleles reference samples. The 13104-qPCR assay reached up to 6.7 DNA copies/reaction for A allele reference sample and 67 DNA copies/reaction for B and E samples. Intra-assay variation results were below 6%. Applicability was determined using DNA samples from animals with known genotype for Ƙ-casein (AA, AB, BB, BE, AE, EE) and both assays were able to discriminate among the six genotypes with 100% accuracy. Thus, this qPCR method represents a sensitive and rapid option for the detection of Ƙ-casein alleles in both hair and milk samples.
  • PublicationOpen Access
    An expression of mixed animal model equations to account for different means and variances in the base population
    (Editions Scientifiques Medicales Elsevier, 1999) Alfonso Ruiz, Leopoldo; Estany Illa, Joan; Producción Agraria; Nekazaritza Ekoizpena
    This paper presents a general expression to predict breeding values using animal models when the base population is selected, i.e. the means and variances of breeding values in the base generation differ among individuals. Rules for forming the mixed model equations are also presented. A numerical example illustrates the procedure.