Open Access
Size and number variation of adipocytes during the growth of Rasa Aragonesa lambs
(CIHEAM, 1995) Purroy Unanua, Antonio; Mendizábal Aizpuru, José Antonio; Soret Lafraya, Beatriz; Horcada, Alberto; Lizaso, G.; Mendizábal Múgica, Francisco Javier; Arana Navarro, Ana; Producción Agraria; Nekazaritza Ekoizpena
The size and number of adipocytes of different fat depots was studied in 45 male lambs of the Rasa Aragonesa breed, distributed in three groups of 15 lambs (G12, G24, G36), slaughtered respectively at 11.7 ± 0.67,24.5 ± 0.57 and 35.8 ± 1.74 kg live weight (LW) and at an age of 32 ± 5, 89 ± 8 and 123 ± 8 days. G12 lambs were slaughtered on the day of weaning, G24 and G36 lambs were weaned respectively at 16.2 ± 1.32 and 18.3 ± 2.46 kg LW and were fed from then onwards on concentrated fodder and barley straw ad libitum until they were slaughtered. The results obtained show that there is a significant increase in the amount of fat deposited in three internal (omental, mesenteric and kidney knob and channel) fat depots as the LW at slaughter increases (P<0.01). A similar phenomenon occurs in the size of the adipocytes, hypertrophy being more evident between 24 and 36 kg (P<0.01) than between 12 and 24 kg, except in the intermuscular fat depot, where the differences were between the two most extreme weight(P <0.01). The number of adipocytes in the omental and mesenteric fat depots increased significantly during the period of the study (P<0.01) while no variation occurred in the kidney knob and channel fat depot during the same period.
Open Access
Acumulación/movilización de reservas grasas: especie caprina versus especie ovina
(Universidad Cardenal Herrera-CEU. Fundación Universitaria San Pablo-CEU, 2002) Mendizábal Aizpuru, José Antonio; Delfa, R.; Eguinoa Ancho, Paola; Arana Navarro, Ana; González, C.; Alzón, M.; Purroy Unanua, Antonio; Producción Agraria; Nekazaritza Ekoizpena
En 20 cabras de raza Blanca Celtibérica (PV: 55,8±12,95Kg.) con notas de condición corporal esternal comprendidas entre 1,5 y 4,5 (3±1,0; escala 0-5) y 20 ovejas de raza Rasa Aragonesa (PV: 55,5±12,46Kg.) con notas de condición corporal lumbar comprendidas entre 1,5 y 4,5 (3±1,0; escala 0-5), todas ellas adultas, secas y vacías, se ha estudiado la variación de la cantidad de grasa en los depósitos grasos omental (OM), mesentérico (MES), pelvicorrenal (PR), subcutáneo (SC) e intermuscular (IM) con la nota de condición corporal (mee). Los resultados obtenidos muestran que, en general, las cabras de raza Blanca Celtibérica presentaban mayor cantidad de grasa que las ovejas de raza Rasa Aragonesa (11.129 frente a 8.450 gr. de grasa total) para una nCC media de 3 y un PV de 56 Kg. en ambas especies. Unicamente, en el depósito PR las ovejas presentaron mayor cantidad de grasa que las cabras (1.878 vs 1636 g). En la especie caprina, la mayor acumulación/movilización de grasa por unidad de variación de la nCC se produjo en el depósito OM (1938 g), mientras que en la especie ovina tuvo lugar en el depósito PR (1219 g). No obstante, si comparamos la variación relativa de cada depósito graso (proporcional al peso medio de cada depósito) ésta tuvo lugar en ambas especies en el subcutáneo, con una variación del 72,5 y 65,3% en las cabras y ovejas, respectivamente.
Open Access
Conformación y engrasamiento de terneros de raza Retinta y cruzados RetintaxPirenaica y RetintaxLimusín
(Asociación Interprofesional para el Desarrollo Agrario, 2005) Mendizábal Aizpuru, José Antonio; Alzón, M.; Arana Navarro, Ana; Albertí, P.; Soret Lafraya, Beatriz; Purroy Unanua, Antonio; Producción Agraria; Nekazaritza Ekoizpena
En el presente trabajo se comparan terneros de raza Retinta en pureza y cruzados con dos razas de aptitud cárnica más mejoradas, la Limusín y la Pirenaica, con la finalidad de profundizar en el conocimiento de los parámetros de conformación y engrasamiento que muestran estos genotipos cruzados.
Open Access
Variación de la actividad lipogénica en cabras de raza Blanca Celtibérica según su estado corporal
(Sociedad Española de Ovinotecnia y Caprinotecnia, 2001) Mendizábal Aizpuru, José Antonio; Delfa, R.; Eguinoa Ancho, Paola; Arana Navarro, Ana; González, C.; Alzón, M.; Purroy Unanua, Antonio; Producción Agraria; Nekazaritza Ekoizpena
En 22 cabras adultas, secas y vacías, de raza Blanca Celtibérica con notas de condición corporal esternal comprendidas entre 1,5 y 4,5, se ha estudiado la variación de la cantidad de grasa, del tamaño y número de adipocitos, y de la actividad de las enzimas lipogénicas Glicerol 3P deshidrogenasa (G3PDH) y Sintetasa de ácidos grasos (FAS) en los depósitos grasos omental (OM), mesentérico (MES), pelvicorrenal (PVR), subcutáneo (SC) e intermuscular (IM) con la nota de condición corporal. Los resultados obtenidos muestran que el depósito graso SC es el que sufre un proceso de acumulación-movilización más intenso, seguido del OM, PVR, MES e IM, en este orden. El tamaño de los adipocitos varió en el mismo sentido que la cantidad de grasa, no observándose, en general, modificaciones en el número de adipocitos al variar la nota de condición corporal. Por último, la actividad de las enzimas G3PDH y FAS no se vió influenciada por la nCC.
Open Access
Predicting beef carcass fatness using an image analysis system
(MDPI, 2021) Mendizábal Aizpuru, José Antonio; Ripoll, Guillermo; Urrutia Vera, Olaia; Insausti Barrenetxea, Kizkitza; Soret Lafraya, Beatriz; Arana Navarro, Ana; Institute on Innovation and Sustainable Development in Food Chain - ISFOOD
The amount and distribution of subcutaneous fat is an important factor affecting beef carcass quality. The degree of fatness is determined by visual assessments scored on a scale of five fatness levels (the SEUROP system). New technologies such as the image analysis method have been developed and applied in an effort to enhance the accuracy and objectivity of this classification system. In this study, 50 young bulls were slaughtered (570 ± 52.5 kg) and after slaughter the carcasses were weighed (360 ± 33.1 kg) and a SEUROP system fatness score assigned. A digital picture of the outer surface of the left side of the carcass was taken and the area of fat cover (fat area) was measured using an image analysis system. Commercial cutting of the carcasses was performed 24 h post-mortem. The fat trimmed away on cutting (cutting fat) was weighed. A regression analysis was carried out for the carcass cutting fat (y-axis) on the carcass fat area (x-axis) to establish the accuracy of the image analysis system. A greater accuracy was obtained by the image analysis (R2 = 0.72; p < 0.001) than from the visual fatness scores (R2 = 0.66; p > 0.001). These results show the image analysis to be more accurate than the visual assessment system for predicting beef carcass fatness.
Open 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.
Open 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.
Open Access
Molecular traceability of beef from synthetic Mexican bovine breeds
(FUNPEC-RP, 2011) Rodríguez Ramírez, R.; Arana Navarro, Ana; Alfonso Ruiz, Leopoldo; González Córdova, A. F.; Torrescano, G.; Guerrero Legarreta, I.; Vallejo Córdoba, B.; Producción Agraria; Nekazaritza Ekoizpena
Traceability ensures a link between carcass, quarters or cuts of beef and the individual animal or the group of animals from which they are derived. Meat traceability is an essential tool for successful identification and recall of contaminated products from the market during a food crisis. Meat traceability is also extremely important for protection and value enhancement of good-quality brands. Molecular meat traceability would allow verification of conventional methods used for beef tracing in synthetic Mexican bovine breeds. We evaluated a set of 11 microsatellites for their ability to identify animals belonging to these synthetic breeds, Brangus and Charolais/Brahman (78 animals). Seven microsatellite markers allowed sample discrimination with a match probability, defined as the probability of finding two individuals sharing by chance the same genotypic profile, of 10-8. The practical application of the marker set was evaluated by testing eight samples from carcasses and pieces of meat at the slaughterhouse and at the point of sale. The DNA profiles of the two samples obtained at these two different points in the productioncommercialization chain always proved that they came from the same animal.
Open Access
Caracterización de las 'Costillas de Palo' de cordero de raza Navarra. I. Composición tisular
(Universidad Cardenal Herrera-CEU. Fundación Universitaria San Pablo-CEU, 2002) Mendizábal Aizpuru, José Antonio; Alzón, M.; Arana Navarro, Ana; Eguinoa Ancho, Paola; Delfa, R.; Beriain Apesteguía, María José; Purroy Unanua, Antonio; Producción Agraria; Nekazaritza Ekoizpena
Se ha estudiado la composición tisular de 46 costillas de palo (10ª y 11ª) procedentes de 23 corderos de raza Navarra sacrificados con 24,2±1,55Kg. de peso vivo y 98±6,3d de edad. El peso medio de la costilla fue de 78,4±10,82g, de los que el porcentaje de músculo supuso el 48,5±4,16%, el de grasa 29,3±4,78% y el de hueso 15,0±3,19%, respectivamente. El músculo Longissimus dorsi, que presentó un área media de 9,6±1,34cm2, supuso el 52,4±6,30% del músculo total de la costilla. El componente óseo se distribuyó en un 41,8% en la costilla y el 58,2% en la vertebra. La grasa subcutánea supuso el 50,1% de la grasa total diseccionada, correspondiendo el 49,9% restante a la intermuscular. Por último, se midió la grasa intramuscular o de veteado que presentaba el músculo Longissimus dorsi, ocupando dicha grasa un 2,5±0,98% de la superficie de dicho músculo. El número medio de vetas de grasa en cada costilla fue de 5,6±1,92 y el tamaño medio de éstas de 4,5±1,74mm2.
Open 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.