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1.
Phys Rev E ; 100(3-1): 032902, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31639897

RESUMO

Hyperuniform states are an efficient way to fill up space for disordered systems. In these states the particle distribution is disordered at the short scale but becomes increasingly uniform when looked at large scales. Hyperuniformity appears in several systems, in static or quasistatic regimes, as well as close to transitions to absorbing states. Here, we show that a vibrated granular layer, at the critical point of the liquid-to-solid transition, displays dynamic hyperuniformity. Prior to the transition, patches of the solid phase form, with length scales and mean lifetimes that diverge critically at the transition point. When reducing the wave number, density fluctuations encounter increasingly more patches that block their propagation, resulting in a static structure factor that tends to zero for small wave numbers at the critical point, which is a signature of hyperuniformity. A simple model demonstrates that this coupling of a density field to a highly fluctuating scalar friction field gives rise to dynamic hyperuniform states. Finally, we show that the structure factor detects better the emergence of hyperuniformity, compared to the particle number variance.

2.
Anim Reprod Sci ; 204: 50-59, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30878392

RESUMO

The cold storage and cryopreservation of semen decrease sperm quality. Morphological and biochemical analyses of spermatozoa provide valuable information for the optimization of storage protocols to obtain a sufficient number of spermatozoa for in vitro fertilization. The aim of this study was to evaluate the morphology and lipid composition of Atlantic salmon (Salmo salar) spermatozoa after storage at 4 °C and cryopreservation. Semen samples were obtained by stripping. One aliquot was stored at 4 °C for 7 days, and another aliquot was cryopreserved. The morphology and ultrastructure were analysed using electron microscopy. The lipid composition was analysed by gas chromatography and a commercial kit. After cold storage, the mitochondrion was the most affected component; however, plasma membrane rupture and detachment of the flagellum were also observed. Morphological abnormalities were greater in cryopreserved spermatozoa. The head and mid-piece were dehydrated, sperm membranes were vesiculated, and alterations of mitochondria were observed. After cold storage and cryopreservation, there were less polyunsaturated and omega-3 fatty acids. Furthermore, there was an increase in saturated fatty acids and decrease in cholesterol concentration after cryopreservation (P < 0.05). Based on the results, cryopreservation drastically damaged sperm membranes; the cryogenic damage was associated with membrane lipid composition alterations. The sperm membranes were affected less by cold storage but there was also a decrease of some lipids; therefore, there is a need for improvement in cold storage processes to decrease structural damage of spermatozoa so that semen cryopreservation can be effectively used in the salmon industry.


Assuntos
Criopreservação/veterinária , Salmo salar , Preservação do Sêmen/veterinária , Animais , Colesterol/metabolismo , Temperatura Baixa , Criopreservação/métodos , Crioprotetores/farmacologia , Ácidos Graxos/metabolismo , Masculino , Lipídeos de Membrana , Preservação do Sêmen/métodos , Motilidade Espermática , Espermatozoides/ultraestrutura
3.
Meat Sci ; 152: 104-108, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30844619

RESUMO

The aim of the present work was to assess consumers' willingness to pay for reformulated frankfurters in the context of the implementation of nutritional warnings. Images of frankfurter packages were designed using a fractional factorial design with 5 2-level variables: brand type, sodium reduction, saturated fat reduction, fibre claim and cholesterol claim. An online study with 548 consumers was implemented with Chilean participants, who were asked to indicate how much they would be willing to pay for each of the packages. Data were analysed using analysis of variance and hierarchical cluster analysis. Willingness to pay was significantly affected by brand type and sodium and fat reduction, whereas fibre and cholesterol claim did not have a significant effect. These results suggest that in the context of the implementation of nutritional warnings reformulation of processed meat products should focus on the reduction of key nutrients, although consumers may not be willing to pay a higher price for reformulated products.


Assuntos
Comportamento do Consumidor/economia , Rotulagem de Alimentos , Produtos da Carne/economia , Adulto , Chile , Colesterol na Dieta , Informação de Saúde ao Consumidor , Gorduras na Dieta , Fibras na Dieta , Feminino , Preferências Alimentares/psicologia , Humanos , Masculino , Valor Nutritivo , Sódio na Dieta , Inquéritos e Questionários
4.
Phys Rev Lett ; 119(7): 078001, 2017 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-28949660

RESUMO

A lattice model for active matter is studied numerically, showing that it displays wetting transitions between three distinctive phases when in contact with an impenetrable wall. The particles in the model move persistently, tumbling with a small rate α, and interact via exclusion volume only. When increasing the tumbling rates α, the system transits from total wetting to partial wetting and unwetting phases. In the first phase, a wetting film covers the wall, with increasing heights when α is reduced. The second phase is characterized by wetting droplets on the wall with a periodic spacing between them. Finally, the wall dries with few particles in contact with it. These phases present nonequilibrium transitions. The first transition, from partial to total wetting, is continuous and the fraction of dry sites vanishes continuously when decreasing the tumbling rate α. For the second transition, from partial wetting to dry, the mean droplet distance diverges logarithmically when approaching the critical tumbling rate, with saturation due to finite-size effects.

5.
Anim Reprod Sci ; 183: 132-142, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28606404

RESUMO

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.


Assuntos
Criopreservação/veterinária , Dieta/veterinária , Óleos de Peixe/administração & dosagem , Lipídeos/química , Preservação do Sêmen/veterinária , Ovinos , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Suplementos Nutricionais , Masculino , Sêmen/química , Análise do Sêmen
6.
Nat Commun ; 8: 15431, 2017 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-28580937

RESUMO

The spreading of mesenchymal-like cell layers is critical for embryo morphogenesis and tissue repair, yet we know little of this process in vivo. Here we take advantage of unique developmental features of the non-conventional annual killifish embryo to study the principles underlying tissue spreading in a simple cellular environment, devoid of patterning signals and major morphogenetic cell movements. Using in vivo experimentation and physical modelling we reveal that the extra-embryonic epithelial enveloping cell layer, thought mainly to provide protection to the embryo, directs cell migration and the spreading of embryonic tissue during early development. This function relies on the ability of embryonic cells to couple their autonomous random motility to non-autonomous signals arising from the expansion of the extra-embryonic epithelium, mediated by cell membrane adhesion and tension. Thus, we present a mechanism of extra-embryonic control of embryo morphogenesis that couples the mechanical properties of adjacent tissues in the early killifish embryo.


Assuntos
Padronização Corporal , Movimento Celular , Peixes/embriologia , Morfogênese , Animais , Blástula/metabolismo , Caderinas/metabolismo , Adesão Celular , Embrião não Mamífero , Desenvolvimento Embrionário , Células Epiteliais/citologia , Feminino , Técnica Indireta de Fluorescência para Anticorpo , Proteínas de Fluorescência Verde/metabolismo , Hibridização In Situ , Masculino , Microinjeções , Microscopia Confocal , RNA Mensageiro/metabolismo , Fatores de Tempo
7.
Exp Biol Med (Maywood) ; 242(10): 1104-1114, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27190274

RESUMO

The mechanistic evidence to support the cardioprotective effects of polyunsaturated fatty acids (PUFA) are controversial. The aim was to test cardioprotective mechanisms induced by PUFA supplementation against cardiac ischemia-reperfusion (IR) injury. Ten-week-old male Wistar rats (225 ± 14 g, n = 14) were divided in two groups: rats without supplementation ( n = 7) and a PUFA group, supplemented by PUFA (0.6 g/kg/day; DHA:EPA = 3:1) for eight weeks ( n = 7). Hearts were perfused with Krebs-Henseleit buffer for 20 min (control conditions); others were subjected to control conditions, 30 min of global ischemia and 120 min of reperfusion (IR group). Infarct size (IS) and left ventricular developed pressure (LVDP) were measured at 120 min of reperfusion. Oxidative stress biomarkers (TBARS, total carbonyls), antioxidant status (CAT, catalase; SOD, superoxide dismutase; GSH-Px, glutathione peroxidase activity and GSH/GSSG ratio), myeloperoxidase activity, ATP levels and nuclear transcription factor erythroid 2-related factor 2 (Nrf2) and nuclear factor kappaB (NF-κB) were determined in both experimental conditions. At the end of reperfusion, hearts supplemented with PUFA showed lower IS and a higher LVDP compared with the nonsupplemented rats. Hearts in the group supplemented with PUFA showed lower levels of oxidative stress markers and higher antioxidant activity, decreased MPO activity and NF-κB and Nrf2 activation compared with the nonsupplemented group. Cardioprotective effects of PUFA are exerted through induction of anti-inflammatory and antioxidant mechanism at tissue level.


Assuntos
Cardiotônicos/administração & dosagem , Ácidos Graxos Insaturados/administração & dosagem , Fator 2 Relacionado a NF-E2/biossíntese , NF-kappa B/antagonistas & inibidores , Traumatismo por Reperfusão/prevenção & controle , Animais , Inibição Psicológica , Masculino , Miocárdio/patologia , Ratos Wistar , Resultado do Tratamento , Função Ventricular Esquerda
8.
Phys Rev E ; 94(2-1): 022603, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27627356

RESUMO

The emergence of clustering and coarsening in crowded ensembles of self-propelled agents is studied using a lattice model in one dimension. The persistent exclusion process, where particles move at directions that change randomly at a low tumble rate α, is extended allowing sites to be occupied by more than one particle, with a maximum n_{max} per site. Three phases are distinguished. For n_{max}=1 a gas of clusters form, with sizes distributed exponentially and no coarsening takes place. For n_{max}≥3 and small values of α, coarsening takes place and few large clusters appear, with a large fraction of the total number of particles in them. In the same range of n_{max} but for larger values of α, a gas phase where a negligible fraction of particles takes part of clusters. Finally, n_{max}=2 corresponds to a crossover phase. The character of the transitions between phases is studied extending the model to allow n_{max} to take real values and jumps to an occupied site are probabilistic. The transition from the gas of clusters to the coarsening phase is continuous and the mass of the large clusters grows continuously when varying the maximum occupancy, and the crossover found corresponds to values close to the transition. The second transition, from the coarsening to the gaseous phase, can be either continuous or discontinuous depending on the parameters, with a critical point separating both cases.

9.
PLoS One ; 11(8): e0160988, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27529819

RESUMO

Boar semen cryopreservation remains a challenge due to the extension of cold shock damage. Thus, many alternatives have emerged to improve the quality of frozen-thawed boar sperm. Although the use of seminal plasma arising from boar sperm-rich fraction (SP-SRF) has shown good efficacy; however, the majority of actual sperm evaluation techniques include a single or dual sperm parameter analysis, which overrates the real sperm viability. Within this context, this work was performed to introduce a sperm flow cytometry fourfold stain technique for simultaneous evaluation of plasma and acrosomal membrane integrity and mitochondrial membrane potential. We then used the sperm flow cytometry fourfold stain technique to study the effect of SP-SRF on frozen-thawed boar sperm and further evaluated the effect of this treatment on sperm movement, tyrosine phosphorylation and fertility rate (FR). The sperm fourfold stain technique is accurate (R2 = 0.9356, p > 0.01) for simultaneous evaluation of plasma and acrosomal membrane integrity and mitochondrial membrane potential (IPIAH cells). Centrifugation pre-cryopreservation was not deleterious (p > 0.05) for any analyzed variables. Addition of SP-SRF after cryopreservation was able to improve total and progressive motility (p < 0.05) when boar semen was cryopreserved without SP-SRF; however, it was not able to decrease tyrosine phosphorylation (p > 0.05) or improve IPIAH cells (p > 0.05). FR was not (p > 0.05) statistically increased by the addition of seminal plasma, though females inseminated with frozen-thawed boar semen plus SP-SRF did perform better than those inseminated with sperm lacking seminal plasma. Thus, we conclude that sperm fourfold stain can be used to simultaneously evaluate plasma and acrosomal membrane integrity and mitochondrial membrane potential, and the addition of SP-SRF at thawed boar semen cryopreserved in absence of SP-SRF improve its total and progressive motility.


Assuntos
Criopreservação , Citometria de Fluxo/métodos , Sêmen/citologia , Espermatozoides/citologia , Acrossomo/metabolismo , Animais , Membrana Celular/metabolismo , Sobrevivência Celular , Fertilidade , Cinética , Masculino , Membranas Mitocondriais/metabolismo , Fosforilação , Análise do Sêmen , Sus scrofa , Tirosina/metabolismo
10.
Theriogenology ; 82(6): 884-9, 2014 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-25108794

RESUMO

High levels of reactive oxygen species (ROS), which may be related to reduced semen quality, are detected during semen cryopreservation in some species. The objectives of this study were to measure the oxidative stress during ram semen cryopreservation and to evaluate the effect of adding 2 antioxidant mimics of superoxide dismutase (Tempo and Tempol) during the cooling process on sperm motility, viability, acrosomal integrity, capacitation status, ROS levels, and lipid peroxidation in frozen and/or thawed ram spermatozoa. Measuring of ROS levels during the cooling process at 35, 25, 15, and 5 °C and after freezing and/or thawing showed a directly proportional increase (P < 0.05) when temperatures were lowering. Adding antioxidants at 10 °C confered a higher motility and sperm viability after cryopreservation in comparison with adding at 35 °C or at 35 °C/5 °C. After freezing and/or thawing, sperm motility was significantly higher (P < 0.05) in Tempo and Tempol 1 mM than that in control group. Percentage of capacitated spermatozoa was lower (P < 0.05) in Tempo and Tempol 1 mM in comparison with that in control group. In addition, ROS levels and lipid peroxidation in group Tempo 1 mM were lower (P < 0.05) than those in control group. These results demonstrate that ram spermatozoa are exposed to oxidative stress during the cooling process, specifically when maintained at 5 °C and that lipid peroxidation induced by high levels of ROS decreases sperm motility and induces premature sperm capacitation. In contrast, the addition of Tempo or Tempol at 0.5 to 1 mM during the cooling process (10 °C) protects ram spermatozoa from oxidative stress.


Assuntos
Crioprotetores/farmacologia , Óxidos N-Cíclicos/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária , Ovinos/fisiologia , Espermatozoides/efeitos dos fármacos , Animais , Criopreservação/veterinária , Óxidos N-Cíclicos/administração & dosagem , Masculino , Espermatozoides/fisiologia , Marcadores de Spin
11.
Rev. colomb. cienc. pecu ; 26(4): 263-269, oct.-dic. 2013. ilus, tab
Artigo em Inglês | LILACS-Express | ID: lil-703353

RESUMO

Background: in recent years, market attention has increasingly focused on improving the quality of dairy products. Therefore, animal selection for healthier milk fatty acid composition are therefore of interest. Objective: the aim of this study was to identify whether two polymorphisms (c.878T>C in the SCD gene and g.17924A>G in the FASN gene) are related with the fatty acid composition of milk. Methods: individual milk samples were collected from 50 Chilean Black Friesian cows. Fatty acids (FA) from each milk sample were extracted, analyzed, and quantified (mg FA/g of milk) by gas chromatography. The genotype of each sample was also determined using PCR-RFLP (Polymerase Chain Reaction - Restriction Fragment Length Polymorphism). Results: milk from cows with a c.878CC genotype in the SCD gene exhibited a greater content of C14:1, C17:1, C18:1n9t, C18:1n9c, and total monounsaturated fatty acids (MUFA), as well as a higher 14:1/14 ratio than other SCD genotypes. In addition, considering the importance of the predominant isomer of conjugated linoleic acid for human diet, we identified a higher content of cis-9, trans-11 conjugated linoleic acid in milk samples from animals that had the c.878CC genotype. For the FASN gene, cows with the g.17924GG genotype presented high contents of C14:0, C16:0, C18:0, C18:1n9t, C18:1n9c, and MUFA. Conclusion: therefore, these polymorphisms could be useful genetic markers for studying the fatty acid composition of dairy milk.


Antecedentes: en los últimos años, la atención del mercado se ha centrado cada vez más en mejorar la calidad los productos lácteos. Por lo tanto, la selección de animales con una composición de ácidos grasos de leche más saludable es de interés. Objetivo: el principal objetivo de este estudio fue identificar dos polimorfismos (c.878T>C en el gen SCD y g.17924A>G en el gen FASN) y su relación con la composición de ácidos grasos de leche. Métodos: muestras individuales de leche fueron recolectadas de 50 vacas Frison Negro Chileno. Los ácidos grasos (FA) de cada muestra de leche fueron extraídos, analizados y cuantificados (mg FA/g leche) por cromatografía de gases. El genotipo de cada muestra se determinó mediante la técnica PCR-RFLP (reacción en cadena de la polimerasa - polimorfismo de longitud de fragmentos de restricción). Resultados: los animales con el genotipo c.878CC en el gen SCD presentaron un mayor contenido de C14:1, C17:1, C18:1n9t, C18:1n9c y total de ácidos grasos monoinsaturados (MUFA), así como elevados índices de 14:1/14 que otros genotipos SCD. Además, debido a la importancia en la dieta humana del isómero predominante de ácido linoleico conjugado (CLA), hemos identificado un mayor contenido de cis-9, trans-11 CLA en muestras de leche de animales que poseen el genotipo c.878CC. Para el gen FASN, vacas con el genotipo g.17924GG presentaron un mayor contenido de C14:0, C16:0, C18:0, C18:1n9t, C18:1n9c y contenido total de ácidos grasos monoinsaturados (MUFA). Conclusión: por lo tanto, estos polimorfismos podrían servir como marcadores genéticos para el estudio de la composición de ácidos grasos en la leche de vaca.


Antecedentes: nos últimos anos, o mercado fornecedor de laticínios tem-se voltado ao melhoramento da qualidade dos seus produtos. Por conseguinte, é de interesse a seleção de animais que apresentem uma composição de ácidos graxos mais saudáveis no seu leite. Objetivo: o objetivo principal deste estudo foi identificar dois polimorfismos (c.878T>C no gene SCD e g.17924A>G no gene FASN) e sua associação com a composição de ácidos graxos do leite. Métodos: as amostras de leite foram coletadas de 50 vacas Frison Preto Chileno. Os ácidos graxos (FA) de cada amostra de leite foram extraídos, analisados e quantificados (mg FA/g leite) por cromatografia gasosa. O genótipo de cada amostra foi determinado pela reação de PCR-RFLP (Reação em cadeia de polimerase - polimorfismo de comprimento dos fragmentos de restrição). Resultados: os animais com o genótipo c.878CC no gene SCD têm um teor mais elevado de C14:1, C17:1, C18:1n9t, C18:1n9c e do total de ácidos graxos monoinsaturados (AGM), além de níveis mais elevados de 14:1/14 que outros genótipos SCD. Além disto, devido à importância na dieta humana do isômero predominante do ácido linoléico conjugado (CLA), identificou-se um maior teor de cis-9, trans-11 CLA nas amostras de leite de animais que tinham o genótipo c.878CC. Para o gene FASN, as vacas com o genótipo g.17924GG tinham um teor mais elevado de C14:0, C16:0, C18:0, C18:1n9t, C18:1n9c e AGM. Conclusão: estes polimorfismos poderiam ser usados como marcadores genéticos para o estudo da composição de ácidos graxos do leite de vaca.

12.
PLoS Comput Biol ; 9(3): e1002944, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23505356

RESUMO

Modelling the displacement of thousands of cells that move in a collective way is required for the simulation and the theoretical analysis of various biological processes. Here, we tackle this question in the controlled setting where the motion of Madin-Darby Canine Kidney (MDCK) cells in a confluent epithelium is triggered by the unmasking of free surface. We develop a simple model in which cells are described as point particles with a dynamic based on the two premises that, first, cells move in a stochastic manner and, second, tend to adapt their motion to that of their neighbors. Detailed comparison to experimental data show that the model provides a quantitatively accurate description of cell motion in the epithelium bulk at early times. In addition, inclusion of model "leader" cells with modified characteristics, accounts for the digitated shape of the interface which develops over the subsequent hours, providing that leader cells invade free surface more easily than other cells and coordinate their motion with their followers. The previously-described progression of the epithelium border is reproduced by the model and quantitatively explained.


Assuntos
Movimento Celular/fisiologia , Células Epiteliais/fisiologia , Epitélio/fisiologia , Modelos Biológicos , Animais , Simulação por Computador , Cães , Células Epiteliais/citologia , Células Madin Darby de Rim Canino , Processos Estocásticos
13.
Salud(i)ciencia (Impresa) ; 18(7): 656-658, nov. 2011.
Artigo em Espanhol | LILACS | ID: lil-654090

RESUMO

Los consumidores prefieren el producto no transgénico, pero se muestran positivos hacia una modificación que incorpore caracteres beneficiosos para la salud.


Assuntos
Alimentos Geneticamente Modificados , Carne , Consumo de Alimentos
14.
Int. j. morphol ; 28(4): 1107-1111, dic. 2010. ilus
Artigo em Inglês | LILACS | ID: lil-582897

RESUMO

Once livestock is slaughtered the carcass of body obtained represents the main commercial product, and is valued in terms of quality. The aim of this work was to characterize and evaluate the carcasses of Araucano creole lambs. Thirteen Araucano lambs were slaughtered at 221+/-15 days of age weighing 32+/-2 Kg. The hot carcass was weighed and after 24 hours at 4C the cold carcass was weighed. The characteristics of conformation, fat cover and regional composition of the carcass were evaluated according to Chilean regulation standards. The tissue composition of the back was also determined, in its three components (muscle, bone and fat). The commercial yield of the carcass was 51.14 percent and losses due to dehydration of the carcass were recorded at 3 percent. The carcasses were characterized as 77cm long and 24cm wide at chest level. According to the thickness of muscle and fat, they were qualified as lean carcasses and the area of Longissimus dorsi muscle was an average of 15 cm2. The regional composition of the carcass presented a high percentage of lean pieces, forequarter (38.9 percent) and let (28.9 percent) with 59.5 percent) of the regional composition being the first category pieces with a high commercial value. The carcasses of the Araucano creole lambs were classified as heavy, of average length with a yield greater than 50 percent of good conformation and average fat cover. These characteristics indicate that this cattle can be defined as an attractive genetic resource for meat production in Southern Chile.


Una vez sacrificados los animales de abasto se obtiene la carcasa o canal, ésta representa el principal producto comercial y se valora en términos 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 días de edad. Se pesó la carcasa caliente, y luego de 24 horas a 4C se pesó la carcasa fría. Se evaluó en el laboratorio las características de conformación, engrasamiento de la carcasa y se evaluó la composición regional de la carcasa de acuerdo a la norma chilena. Determinándose también la composición tisular de la espalda en sus tres componentes (músculo, hueso y grasa). El rendimiento comercial de la carcasa fue de un 51,14 por ciento y las pérdidas por deshidratación de la carcasa fueron de un 3 por ciento. Las carcasas se caracterizaron por tener un largo de 77 cm y un ancho a nivel del tórax de 24 cm. Según el espesor de músculo y grasa (GR) fueron calificadas como carcasas magras y el área del músculo longísimo del dorso alcanzó un promedio 15 cm2. La composición regional de la carcasa presentó un alto porcentaje de piezas magras: cuarto delantero (38,9 por ciento) y pierna (28,9 por ciento), correspondiendo el 59,5 por ciento de la composición regional a piezas de primera categoría, de alto valor comercial. Las carcasas de corderos criollos Araucanos se clasificaron como pesadas, de longitud media, con un rendimiento superior al 50 por ciento, de buena conformación y engrasamiento medio, características que permiten definir a este ovino como un atractivo recurso zoogenético para la producción de carne en la zona sur de Chile.


Assuntos
Animais , Composição Corporal , Ovinos/anatomia & histologia , Chile , Produtos da Carne
15.
Rev. cient. (Maracaibo) ; 20(5): 537-545, oct. 2010. ilus, graf
Artigo em Espanhol | LILACS-Express | ID: lil-631095

RESUMO

Considerando que las actitudes respecto a la biotecnología dependen del organismo sobre el cual se aplica y del tipo de modificación realizada se determinó la importancia del tipo de modificación genética (MG) en la compra de carne bovina en consumidores de Temuco (Región de La Araucanía, Chile) en diferentes segmentos de mercado, mediante una encuesta a 400 personas. Utilizando análisis de conjunto se determinó que el tipo de MG fue más importante que el precio en la compra (66,2 y 33,8%; respectivamente). Mediante análisis de conglomerados jerárquicos se distinguieron dos segmentos principales con diferencias significativas en la importancia de estos atributos. El segmento mayoritario (63,8%) dio alta importancia al tipo de MG, el segundo segmento (28,2%) atribuyó mayor importancia al precio, pero los consumidores de ambos segmentos prefirieron carne de un animal sin MG o de un animal con MG para disminuir el contenido de colesterol y rechazaron la carne de un animal alimentado con granos MG o de animales con MG para reducir el costo de alimentación. Los segmentos presentaron diferencias según el tamaño del grupo familiar, frecuencia de consumo de carne bovina y estilo de vida. Es posible concluir que la ausencia de MG en carne bovina es una condición deseable para los consumidores de Temuco, sin embargo, la totalidad de la muestra encuestada se muestra positiva hacia la carne de un animal MG que presente beneficios para la salud y el 8% acepta carne de un animal alimentado con granos MG.


Considering that attitudes to biotechnology depend on the organism to which it is applied and the type of modification made, a survey was carried out on 400 persons to determine the importance of the type of genetic modification (GM) in the purchase of beef by consumers in Temuco (La Araucanía Region, Chile) in different market segments. Using conjoint analysis it was determined that the type of GM was more important than the price in the purchase decision (66.2 and 33.8%, respectively). Two principal segments were identified by analysis of hierarchical conglomerates, with significant differences in the importance of these attributes. The majority segment (63.8%) attached great importance to the type of GM, the second segment (28.2%) attributed more importance to the price, however consumers of both segments preferred meat from an animal without GM or one with GM to reduce the cholesterol content, and rejected meat from an animal fed with GM grain or subjected to GM to reduce feeding costs. The segments presented differences related to the size of the family group, frequency of beef consumption and life-style. It may be concluded that the absence of GM in beef is a desirable condition for the consumers of Temuco, however the whole sample responded positively to meat from a GM animal which presents health benefits and 8% accept meat from an animal which has been fed with GM grain.

16.
Int. j. morphol ; 28(2): 489-495, June 2010. ilus
Artigo em Espanhol | LILACS | ID: lil-577142

RESUMO

El ovino criollo Araucano presente en la región de La Araucanía, Chile, actualmente se encuentra amenazado por el mestizaje de su material genético con razas productoras de carne como la Suffolk. Con el objetivo de realizar su caracterización racial, se evaluaron 94 hembras provenientes de diferentes rebaños de la región de la Araucanía, Chile. Se determinó el peso vivo y 14 medidas morfológicas a partir de las cuales se calcularon 9 índices zoométricos: cefálico (ICE), pelviano (IPE), corporal (ICO), proporcionalidad (IPRO), profundidad relativa del tórax (IPRP), dáctilo torácico (IDT), pelviano transversal (IPET), pelviano longitudinal (IPEL) y espesor relativo de la caña (IERC). Además de cada animal se obtuvieron características morfológicas y fanerópticas. Del análisis estadístico descriptivo se observó que de las medidas zoométricas evaluadas presentaron un rango de variación entre 4,97 por ciento (para la ALC) y 14,9 por ciento (para el AGP), reflejando que la muestra evaluada presentó un grado medio a alto de homogeneidad. Respecto a los índices zoométricos las ovejas Araucanas se caracterizaron por ser brevilíneas (ICO=75,40 +/- 6,27), de formatos grandes de acuerdo al índice dáctilo-torácico (10,63 +/- 0,91) y presentan una grupa convexilínea (IPE<100). De acuerdo a los índices IPET e IPEL existe una tendencia al desarrollo del tejido muscular en la zona de cortes más valiosos. Respecto las características morfológicas y fanerópticas se destaca que los ovinos Araucanos son animales que presenta un perfil cefálico recto, mucosas generalmente negras, orejas medianas y horizontales, son animales ventrudos, de ubre pequeña sin pigmentación, y de extremidades con pezuñas oscuras. Los resultados obtenidos desprenden índices zoométricos elevados respecto a otros genotipos ovinos, presentando la oveja Araucana tendencia a la aptitud cárnica, capacidad que podría asegurar su conservación al permitir aplicar criterios selectivos que conduzcan a una menor...


The Araucano Creole sheep of the Araucanía region in Chile is currently threatened with the cross-breeding of its genetic material with meat-producing breeds like the Suffolk. In order to characterize the breed, 94 females from different flocks from the Araucanía region were evaluated. The live weight was determined, and 9 zoometric indices were calculated from 14 morphological measurements: cephalic (ICE), pelvic (IPE), corporal (ICO), proportionality (IPRO), relative depth of the thorax (IPRP), dactyl-thoracic (IDT), transversal pelvic (IPET), longitudinal pelvic (IPEL) and relative thickness of the cannon bone (IERC). In addition, the morphological and phaneroptic features were obtained from each animal. It was observed from the descriptive analysis that of the evaluated zoometric measurements, there was a range of variation between 4.97 percent (for the ALC) and 14.9 percent (for the AGP), reflecting that the sample evaluated presented a medium to high degree of homogeneity. With respect to the zoometric indices, the Araucano sheep were characterized as being brevilineal (ICO=75.40 +/- 6.27), large-sized according to the dactyl-thoracic index (10.63 +/- 0.91) and presented hindquarters with a convex curve (IPE<100). According to the IPET and IPEL indices, there is a tendency toward the development of muscle tissue in the area of the most valuable cuts. Of the morphological and phaneroptic features, it is noteworthy that Araucano sheep have a straight cephalic profile, generally black mucous membranes, medium-sized horizontal ears, are pot-bellied with a small udder without pigmentation and have extremities with dark hooves. The results obtained provide high zoometric indices with respect to other ovine genotypes, and the Araucano sheep has a tendency to meat aptitude, a capacity that could ensure its conservation when allowing selective criteria to be applied that lead to a lower variability in the ethnological and functional characters.


Assuntos
Animais , Feminino , Anatomia Veterinária , Ovinos/anatomia & histologia , Chile , Variação Genética , Ovinos/genética
17.
Rev. cient. (Maracaibo) ; 20(1): 101-109, feb. 2010. tab
Artigo em Espanhol | LILACS-Express | ID: lil-631049

RESUMO

El objetivo de este estudio fue evaluar la importancia de 21 atributos intrínsecos y extrínsecos en la compra de la carne bovina y la existencia de diferentes segmentos de consumidores en el sur de Chile. Para esto se realizaron encuestas directas a 400 consumidores de la ciudad de Temuco, Región de La Araucanía. Los consumidores atribuyeron mayor importancia a los atributos intrínsecos relacionados con las propiedades organolépticas de la carne y con el cuidado de la salud. Mediante análisis cluster se distinguieron tres segmentos de mercado, el más numeroso (54,5%) otorga baja importancia a los atributos relacionados con el sistema de producción, origen y respeto por el medio ambiente, el segundo grupo en importancia (27,5%) valora, tanto atributos intrínsecos como extrínsecos de la carne, mientras el grupo minoritario (18,0%) atribuye baja importancia a los atributos asociados al sistema de producción del animal.


The aim of this study was to evaluate the importance of 21 intrinsic and extrinsic attributes on the purchase of beef and the existence of different consumer segments in southern Chile. To do this, direct surveys were performed on 400 consumers in Temuco, Region of the Araucanía. The consumers attributed greatest importance to the intrinsic cues related to the organoleptic quality of the meat and to health care. Using a cluster analysis, three market segments were distinguished: the largest (54.5%) placed low importance on the cues related to the production system, origin and respect for the environment, the second group in importance (27.5%) valued both the intrinsic and extrinsic cues of the meat, while the smallest group (18.0%) placed low importance on the cues associated with the animal production system.

18.
Rev. cient. (Maracaibo) ; 18(6): 725-733, nov.-dic. 2008. tab
Artigo em Espanhol | LILACS | ID: lil-551194

RESUMO

Considerando el aumento de las importaciones de carne bovina en Chile, se evaluó la existencia de diferentes segmentos de consumidores según la importancia relativa del origen en la compra de la carne bovina, aceptación y disposición a pagar por carne de diferente origen en la zona centro-sur de Chile. Para esto se realizaron encuestas directas a 400 consumidores de la ciudad de Temuco, Región de La Araucanía, y 400 de la ciudad de Talca, Región del Maule. Mediante análisis conjunto se determinó que el origen de la carne bovina fue más importante que el precio y el envase en la decisión de compra. Los consumidores prefirieron la carne nacional y argentina y rechazaron la carne brasileña, pero no están dispuestos a pagar un precio considerablemente mayor por las carnes preferidas. Mediante análisis cluster se distinguieron tres segmentos de mercado, el más numeroso (50,5 por ciento) concede gran importancia al origen de la carne, el segundo grupo en importancia (32,3 por ciento) considera levemente más importante el precio que el envasado y el origen, mientras para el grupo minoritario (17,3 por ciento) el precio fue el factor más relevante en la compra de la carne bovina.


Considering the increase in beef imports to Chile, different consumer segments were determined and evaluated according to the relative importance of the origin when purchasing beef, acceptance and the willingness to pay for beef from an area other than the central-southern region of Chile. To do this, direct surveys were conducted on 400 consumers from Temuco, in the Región de La Araucanía, and 400 from Talca, in the Región del Maule. Using a conjoint analysis, it was established that the origin of beef was more important than price and packaging in the purchasing decision. Consumers preferred domestic and Argentinean beef and rejected Brazilian beef, but were not willing to pay a considerably higher price for the preferred beef. Using a cluster analysis, three market segments were distinguished: the most numerous (50.5%) placed the greatest importance on the origin of the beef, the second largest group (32.3%) considered price slightly more important than packing and origin, whereas for the smallest group (17.3%), price was the most significant factor when purchasing beef.


Assuntos
Indústria Agropecuária/economia , Carne , Indústria da Carne
19.
Rev. cient. (Maracaibo) ; 17(6): 606-613, nov.-dic. 2007. tab, graf
Artigo em Espanhol | LILACS | ID: lil-548561

RESUMO

Considerando la importancia de la producción y el consumo de carne bovina en Chile, se estudió el comportamiento de los márgenes de comercialización y su efecto en el precio pagado al productor y el impacto que los cambios en los precios pagados al productor y en la magnitud de la demanda ejercen sobrela dinámica temporal de los márgenes comerciales de la carne bovina en Chile, entre 1990 y 2005. Se determinó un aumento de los márgenes comerciales de la carne bovina junto a una disminución de la participación del productor en el precio final del producto. La mayor proporción del margen comercial total corresponde a los agentes minoristas, pero son los mayoristas quienes han aumentado relativamente más su participación. Utilizando series mensuales de precios y márgenes de comercialización, entre 1990 y 2005, se estimó la ecuación de regresión múltiple que relaciona los precios pagados al productor como variable dependiente y los márgenes mayorista y minorista, como variables explicativas. Se obtuvo un efecto negativo de ambos márgenes, expresados en valor absoluto y relativo, en los precios pagados al productor de carne bovina. Mediante la estimación de un modelo dinámico de márgenes comerciales, utilizando series mensuales de precios y cantidades producidas de carne en vara entre 1998 y 2005, se comprobó la relación inversa entre los cambios en los precios pagados al productor y la evolución de los márgenes comerciales en los canales de distribución de carne bovina. No se encontró evidencia que respalde que incrementos temporales en lascantidades demandadas de carne provoquen reducciones en los márgenes comerciales de este producto alimenticio.


Considering the importance of the production and the consumption of cattle meat in Chile, there was studied the behavior of the margins of marketing and its effect in the price paid to the producer and, the impact that the changes in the prices paid to the producer and in the magnitude of the demand exercise on the temporary dynamics of the commercial margins of cattle meat in Chile between 1990 and 2005. There decided an increase of the commercial margins of the cattle meat close to a decrease of the participation of the producer in the final price of the product. The major proportion of the commercial total margin corresponds to the agents retailers, but they are the wholesalers whom have increased relatively more its participation. Using monthly series of prices and margins of marketing between 1990 and 2005, there was thought the equation of multiple regression that relates the prices paid to the producer as dependent variable and the margins wholesaler and retailer as explanatory variables. There was obtained a negative effect of both margins, expressed in absolute and relative value, in the prices paid to the producer of bovine meat. By means of the estimation of a dynamical model of commercial margins using monthly series of prices and quantities produced of meat in rod between 1998 and 2005, there was verified the inverse relationship between the changes in the prices paid to the producer and the evolution of the commercial margins in the distributions channels of bovine meat. There is not evidence that endorses that temporary increases in the quantities demanded of meat provoke reductions in the commercial margins of this food product.


Assuntos
Bovinos , Animais , Comércio/economia , Produção de Alimentos , Indústria Agropecuária/estatística & dados numéricos , Indústria da Carne
20.
Asian J Androl ; 7(3): 303-9, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16110359

RESUMO

AIM: To evaluate two extenders and two cryoprotectant agents (CPA) for alpaca semen cryopreservation. METHODS: Semen samples were obtained from four adult alpacas (Lama pacos) and frozen using extender I (TRIS, citrate, egg yolk and glucose) or extender II (skim milk, egg yolk and fructose), each containing either glycerol (G) or ethylene glycol (EG) as CPA. Consequently, four groups were formed: 1) extender I-G; 2) extender I-EG; 3) extender II-G; and 4) extender II-EG. Semen was diluted in a two-step process: for cooling to 5 degrees (extenders without CPA), and for freezing (extenders with CPA). Viability and acrosome integrity were assessed using trypan blue and Giemsa stains. RESULTS: When compared, the motility after thawing was higher (P >0.05) in groups II-EG (20.0% +/- 6.7%) and II-G (15.3 % +/- 4.1% ) than that in groups I-G (4.0 % +/- 1.1%) and I-EG (1.0 % +/- 1.4%). Viable spermatozoa with intact acrosomes in groups II-EG (18.7 % +/- 2.9%) and II-G (12.7 % +/- 5.9%) were higher than that in groups I-G (5.7% +/- 1.5%) and I-EG (4.0% +/- 1.0%). CONCLUSION: The skim milk- and egg yolk-based extenders containing ethylene glycol or glycerol to freeze alpaca semen seems to promote the survival of more sperm cells with intact acrosomes than the other extenders.


Assuntos
Congelamento , Preservação do Sêmen , Sêmen , Animais , Camelídeos Americanos , Crioprotetores/administração & dosagem , Masculino , Motilidade Espermática
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