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Dive into the research topics where Silvana Bravo is active.

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Featured researches published by Silvana Bravo.


International Journal of Morphology | 2010

Índices zoométricos en ovejas criollas araucanas

Silvana Bravo; Néstor Sepúlveda

El ovino criollo Araucano presente en la region de La Araucania, Chile, actualmente se encuentra amenazado por el mestizaje de su material genetico con razas productoras de carne como la Suffolk. Con el objetivo de realizar su caracterizacion racial, se evaluaron 94 hembras provenientes de diferentes rebanos de la region de la Araucania, Chile. Se determino el peso vivo y 14 medidas morfologicas a partir de las cuales se calcularon 9 indices zoometricos: cefalico (ICE), pelviano (IPE), corporal (ICO), proporcionalidad (IPRO), profundidad relativa del torax (IPRP), dactilo toracico (IDT), pelviano transversal (IPET), pelviano longitudinal (IPEL) y espesor relativo de la cana (IERC). Ademas de cada animal se obtuvieron caracteristicas morfologicas y faneropticas. Del analisis estadistico descriptivo se observo que de las medidas zoometricas evaluadas presentaron un rango de variacion entre 4,97% (para la ALC) y 14,9% (para el AGP), reflejando que la muestra evaluada presento un grado medio a alto de homogeneidad. Respecto a los indices zoometricos las ovejas Araucanas se caracterizaron por ser brevilineas (ICO=75,40±6,27), de formatos grandes de acuerdo al indice dactilo-toracico (10,63±0,91) y presentan una grupa convexilinea (IPE<100). De acuerdo a los indices IPET e IPEL existe una tendencia al desarrollo del tejido muscular en la zona de cortes mas valiosos. Respecto las caracteristicas morfologicas y faneropticas se destaca que los ovinos Araucanos son animales que presenta un perfil cefalico recto, mucosas generalmente negras, orejas medianas y horizontales, son animales ventrudos, de ubre pequena sin pigmentacion, y de extremidades con pezunas oscuras. Los resultados obtenidos desprenden indices zoometricos elevados respecto a otros genotipos ovinos, presentando la oveja Araucana tendencia a la aptitud carnica, capacidad que podria asegurar su conservacion al permitir aplicar criterios selectivos que conduzcan a una menor variabilidad en los caracteres etnologicos y funcionales.


Animal Genetics | 2015

Genotyping of BMPR1B, BMP15 and GDF9 genes in Chilean sheep breeds and association with prolificacy

E. Paz; John Quiñones; Silvana Bravo; H. H. Montaldo; Néstor Sepúlveda

References1 Barzegari A. et al. (2010) Reprod Domest Anim 45, 666–9.2 Galloway S.M. et al. (2000) Nat Genet 25, 279–83.3 Hanrahan J.P. et al. (2004) Biol Reprod 70, 900–9.4 Wilson T. et al. (2001) Biol Reprod 64, 1225–35.5 Paz E. et al. (2014) Arch Med Vet 46, 327–31.6 Silva B.D. et al. (2010) Anim Genet 42,89–92.7 Drummond A. et al. (2012) Geneious v5.6.Correspondence: E. Paz ([email protected])


International Journal of Morphology | 2011

Use of Morphometric Variables for Differentiating Spanish Hound Breeds

Ana González; M Luque; E. Rodero; C González; R Aguilera; J Jiménez; Néstor Sepúlveda; Silvana Bravo; M Herrera

El termino Podencos se refiere a un grupo de razas de perros originarios de Espana y clasificados en el grupo 5 de razas caninas por la Federacion Cinologica Internacional (FCI). El objetivo del presente trabajo fue comparar caracteristicas morfometricas de las razas caninas de Podencos; Canario, Ibecenco, Andaluz (pequeno, medio y grande) y Orito. Se midieron diez variables morfometricas en 385 animales (245 hembras y 140 machos); longitud de la cabeza, la longitud hocico, altura a la cruz, alzada a la grupa, la longitud del cuerpo, ancho de la cabeza, ancho de la grupa, la profundidad del pecho, la circunferencia del pecho y la circunferencia de la cana. Las variables morfoestructurales fueron mas homogeneas en el Podenco Ibicenco y el Podenco Canario, porque por muchos anos fueron fijados gradualmente los rasgos distintivos para los estandares de cada raza. El analisis discriminante manifesto diferencias morfoestructurales entre todas las razas, lo que se refleja en la significativa distancia de Mahalanobis, y confirmo que el podenco Orito puede ser aceptado como una poblacion de perros diferentes.


Andrologia | 2016

Determination of fatty acid profile in ram spermatozoa and seminal plasma

Rommy Díaz; M. A. Torres; Silvana Bravo; R. Sánchez; Néstor Sepúlveda

Fatty acids are important in male reproductive function because they are associated with membrane fluidity, acrosome reaction, sperm motility and viability, but limited information exists about the fatty acid profile of ram semen. Our aim was to determine the fatty acid composition in ram spermatozoa and seminal plasma. Sixty ejaculates were obtained from three ram (20 ejaculates/ram) using artificial vagina. Ram spermatozoa (RS) and seminal plasma (SP) were separated using centrifugation, and the fatty acids were analysed by gas chromatography. Total lipids obtained in ram spermatozoa were 1.8% and 1.6% in seminal plasma. Saturated fatty acid (SFA) was proportionally major in SP (66.6%) that RS (49.9%). The highest proportions of SFA corresponded to C4:0 (RS = 16.3% and SP = 28.8%) and C16:0 (RS = 16.3% and PS = 20%). The most important unsaturated fatty acid (UFA) was docosahexaenoic acid (DHA), 44.9% in RS and 31.5% in SP. The profile of fatty acid and their proportions showed differences between spermatozoa and seminal plasma.


International Journal of Morphology | 2012

Detección del Polimorfismo en el Gen del Receptor de Melatonina (MT1) en la Oveja Criolla Araucana

John Quiñones; Silvana Bravo; E. Paz; Néstor Sepúlveda

La melatonina es una hormona que regula los ciclos circadianos y muchos de los aspectos reproductivos de los mamiferos y es secretada por la glandula pineal en las horas de ausencia de luz. Esta hormona posee receptores de alta afinidad acoplados a proteinas de tipo G, denominados MT1. Un polimorfismo de la secuencia que codifica para estos receptores estaria involucrado en el control de la reproduccion estacional de los ovinos. El proposito de este estudio busca determinar la presencia del polimorfismo del receptor MT1 en la oveja criolla Araucana, un ovino local en el que se ha registrado un corto anestro reproductivo. Para poder realizar este trabajo se utilizo la tecnica denominada reaccion en cadena de la polimerasa para polimorfismo en el tamano de los fragmentos de restriccion PCR-RFLP, para lo cual, se obtuvieron muestras de ADN genomico de 50 ovejas Araucanas, las cuales fueron digeridas con la endonucleasa de restriccion Mnl1. Se logro identificar la presencia del polimorfismo del receptor MT1 en la oveja Araucana. Los genotipos se hallaron en una frecuencia de 68% para el genotipo +/+, 28% para el genotipo +/- y4% para el genotipo -/-. Este alto porcentaje de animales con genotipo +/+ podria explicar el corto anestro reproductivo que presenta esta raza.


Animal Genetics | 2016

Polymorphism of the GDF9 gene associated with litter size in Araucana creole sheep

Silvana Bravo; Giovanni Larama; E. Paz; K. Inostroza; H. H. Montaldo; Néstor Sepúlveda

1 Troost K. (2010) J Sea Res 64, 145–65. 2 Saulnier D. et al. (2009) J Microbiol Methods 77, 191–7. 3 Abolmaaty A. et al. (2007) J Microbiol Methods 68, 349– 52. 4 Thomson L.M. et al. (2005) J Microbiol Methods 63, 95– 8. 5 Wong W.H. et al. (2014) Mol Ecol Resour 14, 1271–80. 6 Demeke T. et al. (2010) Anal Bioanal Chem 396, 1977–90. 7 Peist R. et al. (2001) QIAGEN News 3, 7–9. 8 Wilson I.G. (1997) Appl Environ Microbiol 63, 3741–51. 9 Schrader C. et al. (2012) J Appl Microbiol 113, 1014–26. 10 Huvet A. et al. (2000) Anim Genet 31, 71–2. 11 Sauvage C. et al. (2009) Mol Ecol Resour 9, 853–5.


Archivos De Medicina Veterinaria | 2014

Identificación de los polimorfismos G1 y G8 del gen GDF9 en ovinos criollos Araucanos

E. Paz; John Quiñones; Silvana Bravo; E. Rodero; Ana González; Néstor Sepúlveda

SUMMARY Polymorphisms in major gene effect related to reproductive activity have been described in sheep. Mutations located in the GDF9 gene have been associated with increased ovulation rate and litter size. GDF9 factor is secreted by the oocyte and is a member of the family of transforming growth factors (TGF-β) located on chromosome 5. The aim of this study was to identify the presence of polymorphic regions (G1 and G8) in the GDF9 gene in Araucano creole sheep. DNA was extracted from 100 blood samples and the presence of mutations was determinated using PCR-RFLP. Two regions were amplified, one corresponding to exon 1 of 462 bp digested with restriction enzyme HhaI and a 139bp fragment corresponding to exon 2 digested with enzyme DdeI. The presence of polymorphisms in G1 of GDF9 gene were detected with a genotype frequency of 0.56 (genotype GG), 0.44 (genotype GA) and an allele frequency of 0.78 for the allele (G) and 0.22 for the allele (A). No polymorphisms were detected in G8. This is the first report of this polymorphism in sheep in Chile that could serve as a genetic marker for marker for prolificacy selection in the the Araucano creole sheep.


International Journal of Morphology | 2010

Corporal Composition and Characteristics of Carcass of Araucano Creole Lambs

Silvana Bravo; Macarena Fabres; Berta Schnettler; Néstor Sepúlveda

Una vez sacrificados los animales de abasto se obtiene la carcasa o canal, esta representa el principal producto comercial y se valora en terminos de calidad. El objetivo de este trabajo fue caracterizar y valorar las carcasas obtenidas de corderos criollos Araucanos. Fueron sacrificados 13 corderos Araucanos de 32±2 Kg de peso vivo y de 221±15 dias de edad. Se peso la carcasa caliente, y luego de 24 horas a 4C se peso la carcasa fria. Se evaluo en el laboratorio las caracteristicas de conformacion, engrasamiento de la carcasa y se evaluo la composicion regional de la carcasa de acuerdo a la norma chilena. Determinandose tambien la composicion tisular de la espalda en sus tres componentes (musculo, hueso y grasa). El rendimiento comercial de la carcasa fue de un 51,14% y las perdidas por deshidratacion de la carcasa fueron de un 3%. Las carcasas se caracterizaron por tener un largo de 77 cm y un ancho a nivel del torax de 24 cm. Segun el espesor de musculo y grasa (GR) fueron calificadas como carcasas magras y el area del musculo longisimo del dorso alcanzo un promedio 15 cm2. La composicion regional de la carcasa presento un alto porcentaje de piezas magras: cuarto delantero (38,9%) y pierna (28,9%), correspondiendo el 59,5% de la composicion regional a piezas de primera categoria, de alto valor comercial. Las carcasas de corderos criollos Araucanos se clasificaron como pesadas, de longitud media, con un rendimiento superior al 50%, de buena conformacion y engrasamiento medio, caracteristicas que permiten definir a este ovino como un atractivo recurso zoogenetico para la produccion de carne en la zona sur de Chile.


British Food Journal | 2018

Consumer acceptance of a functional processed meat product made with different meat sources

Berta Schnettler; Néstor Sepúlveda; Silvana Bravo; Klaus G. Grunert; Clementina Hueche

Purpose A study was carried out to explore the consumer acceptance of a functional meat processed product made with different meat sources, and to distinguish the existence of different market segments. Design/methodology/approach Non-probability sampling was used to recruit a sample of 411 consumers in southern Chile, over the age of 18 and responsible for the purchase of meat products for their household. Findings Using a fractional factorial design for conjoint analysis, it was found in the total sample that the meat source of the meat processed product was more important than packaging, region of origin, price and the functional ingredient claim, with preference for lamb and pork meat processed products with omega-3. Two main segments were identified using a cluster analysis; these segments differed according to family size, presence and age of children, ethnic origin, general health interest, quality of diet and level of satisfaction with food-related life. The largest segment (56.0%) shows a high pr...


Animal Reproduction Science | 2017

Dietary inclusion of fish oil changes the semen lipid composition but does not improve the post-thaw semen quality of ram spermatozoa

Rommy Díaz; M. A. Torres; Erwin Paz; John Quiñones; Silvana Bravo; Jorge G. Farías; Néstor Sepúlveda

The aim of this study was to investigate the effects of dietary fish oil (FO) time-response on the fatty acid profile, cholesterol levels and sperm cryosurvival in ram semen. Criollo Araucano rams were randomly assigned to two groups (n=4) according to the type of supplementation: a control group without FO and a supplemented group fed a diet with 3% FO for 8 weeks. The semen lipid profile and post-thaw sperm quality were analyzed at weeks 0 (pre-supplementation), 4, 8, 12 and 16 (post-supplementation) to evaluate the effects of FO supplementation by time interaction. Post-thaw sperm quality was determined by CASA and flow cytometry. In spermatozoa, the supplemented group increased the linoleic acid (C18:2n6c) and docosahexaenoic acid (DHA; C22:6n3) with levels higher at week 16 (P<0.05). The effect of FO on cholesterol concentration in sperm was significant at the end of the experiment (week 16). In seminal plasma, statistical differences of butyric acid (C4:0), palmitic acid (C16:0), stearic acid (C18:0), eicosatrienoic acid (C20:3n3) and DHA were observed at week 12. The cholesterol concentration was not affected by dietary treatments (P>0.05). However, the post-thaw sperm quality of the FO treatment group decreased. Motility percentage decreased 50% and spermatozoa with permeable plasma membrane and reacted acrosome were higher (63%) at week 16 than the control group. These results showed that DHA was effectively incorporated into semen through dietary supplementation with FO, but evaluations of post-thaw sperm quality confirm alteration specificity related to the structure of the lipid bilayer.

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E. Paz

University of La Frontera

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John Quiñones

University of La Frontera

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Macarena Fabres

University of La Frontera

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Rommy Díaz

University of La Frontera

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H. H. Montaldo

National Autonomous University of Mexico

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M. A. Torres

University of São Paulo

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Erwin Paz

University of La Frontera

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