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The Mapuche fowl is an autochthonous breed raised in Chile and represents an important zoogenetic resource for the local economy. This study aimed at investigating the genetic diversity, relationship and population structure of 96 local Chilean chickens derived from 3 ecotype of Mapuche fowl (Kollonka, Ketro, and Kollonka de aretes), 2 ecotype Chilean (Trintre, Cogote pelado) and 2 breeds (Light Brahma and Barred Plymouth Rock) using 12 microsatellite markers. In total, 113 alleles were detected in all populations, with a mean of 7.6 alleles per population. In all population chicken breeds, the observed and expected heterozygosity ranged from 0.91 to 0.98 and from 0.69 to 0.79. Furthermore, all populations showed significant deviations from Hardy-Weinberg expectations. Across each population, the global heterozygosity deficit (FIT) was -0.174, population differentiation index (FST) was 0.073, and the global inbreeding of individuals within breed (FIS) was -0.267. The phylogenetic relationships of chickens were examined using neighbor-joining trees constructed at the level of population. The highest Nei's standard genetic distance value of 0.559 was observed between Barred Plymouth Rock and Light Brahma, whereas the minimum value (0.099) was found between Kollonka and Trintre. The neighbor-joining tree constructed at population level revealed 2 main clusters, with Light Brahma, Barred Plymouth Rock, Ketro and Kollonka de aretes in 1 cluster, and Kollonka, Trintre and Cogote pelado breeds in the second cluster. Based on the results of the STRUCTURE analysis, the most likely number of clustering of the population evaluated was at K = 3, with Light Brahma and Barred Plymouth Rock breeds forming their own distinct clusters, while Kollonka, Ketro, Kollonka de aretes, Trintre and Cogote pelado breeds clustered together. This study represents the first report of genetic diversity in these populations in Chile. These results can be used as baseline genetic information for genetic conservation program, for instance, to control inbreeding and to implement further genetic studies in local Chilean chickens.

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Lipids are fundamental components of cell membranes and play a significant role in their integrity and fluidity. Alteration in lipid composition of membranes has been reported to be a major response to abiotic environmental stresses. This work was focused on the characterization of frond lipid composition and membrane integrity during a desiccation-rehydration cycle of two filmy fern species with contrasting desiccation tolerance: Hymenophyllum caudiculatum (less tolerant) and Hymenophyllum plicatum (more tolerant). The relative water content decreased without differences between species when both filmy ferns were subjected to desiccation. However, H. plicatum reached a higher relative water content than H. caudiculatum after rehydration. Fatty acids profiles showed the presence of a very long chain polyunsaturated fatty acid during the desiccation-rehydration cycle, with eicosatrienoic acid being the most abundant. Additionally, propidium iodide permeation staining and confocal microscopy demonstrated that, following the desiccation-rehydration cycle, H. plicatum exhibited a greater membrane integrity than H. caudiculatum. The lack of some very long chain fatty acids such as C22:1n9 and C24:1n9 in this species contrasting with H. plicatum may be associated with its lower membrane stability during the desiccation-rehydration cycle. This report provides the first insight into the fatty acid composition and dynamics of the membrane integrity of filmy ferns during a desiccation-rehydration cycle. This could potentially play a role in determining the different levels of desiccation tolerance and microhabitat preferences exhibited by Hymenophyllaceae species.

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Araucana creole sheep are a local animal genetic resource adapted to environmental conditions in rural production systems in southern Chile. The aim of the present study was to analyze the milk yield and composition of Araucana creole ewe's milk from ewes maintained in a traditional grazing system of natural pastures. Twenty healthy single-bearing Araucana creole ewes were selected immediately after lambing (body condition score (BCS) of 2.8 ± 0.2, ewe weight (EW) of 62 ± 3.5 kg, and age of 3.8 ± 0.7 years). BCS, EW, and lamb weights were determined. Milk samples were obtained using the oxytocin technique at 10 days postpartum and then twice a month during the lactation stage (90 days). Protein, fat, lactose, total solids (TS), solid non-fat (SNF), urea contents, and fatty acid (FA) composition were analyzed. The Araucana ewe's milk yield was lower than that of other dairy sheep but was higher than that of meat breeds. The milk fat had a higher content of oleic acid in the early lactation period, which decreased slowly according to the progress of lactation. The increase in oleic acid improved the milk health indexes during this period and thus provided a healthier milk product for human consumption than later in lactation. During lactation, higher conjugated linoleic acid (CLA) levels were obtained only at day 60. Our research suggests that Araucana creole sheep can provide high-quality milk during early lactation, which is rich in oleic acid and represents an alternative for the production of dairy products, improving the profitability of the productive systems of small-holder farmers in Chile.

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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.

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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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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.

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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.

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