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Seafood international trade has increased the labeling requirements in standards and regulations to include product information that enable traders and consumers to make informed choices. The European Union (EU) Regulation No. 1379/2013 imposes the declaration of an official commercial designation and scientific names for all the fishery and aquaculture products to be offered for sale to the final consumers. DNA analyses are used to enforce this regulation and to test authenticity in processed foods. We compared the performance of two mono-locus approaches for species identification (SI) in 61 Mytilus mussels: the high-resolution melting analysis of the polyphenolic adhesive protein gene and the partial sequencing of the histone H1C gene. The H1C sequences were analyzed with five different methods. Both approaches show discrepancies in the identification of putative hybrids (0.0

The red cusk-eel (Genypterus chilensis, Guichenot, 1848) is an iconic species in Chilean gastronomy, with a cultural significance that extends beyond its economic value, worthy of conservation. Despite the decline in fishery productivity across most of the distribution range for this species, little effort has been devoted to assessing stock management. In the present study, seven heterologous microsatellite loci (cmrGb3.8.1, cmrGb5.2B, cmrGb4.2A, cmrGb4.2B, cmrGb5.9, cmrGb4.11, and cmrGb2.6.1) were genotyped in a total of 153 individuals from four locations in central and southern Chile (30.5–37.6°S), comprising ∼1,000 km of coastline. Five microsatellite loci were consistently amplified with a low frequency of null alleles (

DNA-based methods using informative markers such as single nucleotide polymorphism (SNPs) are suitable for reliable species identification (SI) needed to enforce compliance with seafood labelling regulations (EU No.1379/2013). We developed a panel of 10 highly informative SNPs to be genotyped by PCR-High resolution melting (HRM) for SI in the Mytilus genus through in silico and in vitro stages. Its fitness for purpose and concordance were assessed by an internal validation process and by the transference to a second laboratory. The method was applicable to identify M. chilensis, M. edulis, M. galloprovincialis and M. trossulus mussels, fresh, frozen and canned with brine, oil and scallop sauce, but not in preserves containing acetic acid (wine vinegar) and tomato sauce. False-positive and negative rates were zero. Sensitivity, expressed as limit of detection (LOD), ranged between 5 and 8 ng/μL. The method was robust against small variations in DNA quality, annealing time and temperature, primer concentration, reaction volume and HRM kit. Reference materials and 220 samples were tested in an inter-laboratory assay obtaining an “almost perfect agreement” (κ = 0.925, p < 0.001). In conclusion, the method was suitable for the intended use and to be applied in the seafood industry.

The yeast Saccharomyces cerevisiae is the main species responsible for the process that involves the transformation of grape must into wine, with the initial nitrogen in the grape must being vital for it. One of the main problems in the wine industry is the deficiency of nitrogen sources in the grape must, leading to stuck or sluggish fermentations, and generating economic losses. In this scenario, an alternative is the isolation or generation of yeast strains with low nitrogen requirements for fermentation. In the present study, we carry out a genetic improvement program using as a base population a group of 70 strains isolated from winemaking environments mainly in Chile and Argentina (F0), making from it a first and second filial generation (F1 and F2, respectively) based in different families and hybrids. It was found that the trait under study has a high heritability, obtaining in the F2 population strains that consume a minor proportion of the nitrogen sources present in the must. Among these improved strains, strain “686” specially showed a marked drop in the nitrogen consumption, without losing fermentative performance, in synthetic grape must at laboratory level. When using this improved strain to produce wine from a natural grape must (supplemented and non-supplemented with ammonium) at pilot scale under wine cellar conditions, a similar fermentative capacity was obtained between this strain and a widely used commercial strain (EC1118). However, when fermented in a non-supplemented must, improved strain “686” showed the presence of a marked floral aroma absent for EC1118 strain, this difference being probably a direct consequence of its different pattern in amino acid consumption. The combination of the capacity of improved strain “686” to ferment without nitrogen addition and produce floral aromas may be of commercial interest for the wine industry.

Mussels (Mytilus spp.) are one of the most cultivated and commercialized bivalves in southern Chile; culture is currently supplied almost entirely from wild-caught seed obtained from relatively few collection centers. The genetic diversity and differentiation of the blue mussel in southern Chile was investigated by sampling six locations: one natural bank and five seed collection centers. Nine polymorphic microsatellite (SSR) loci were genotyped (Mgu1, Mgu3, MT203, MT282, Mg15, Mg56, Med737, MIT02 and MGE005). We found 75 different alleles, six of which were private alleles. Of the analyzed loci, 45 of 54 tests performed deviated from Hardy-Weinberg equilibrium after sequential Bonferroni correction (P < 0.05), revealing significant heterozygote deficiencies. The polymorphic information content (PIC) ranged from 0.322 (MGE005) to 0.893 (Mgu1). Despite the long distance between some sampling sites (up to 1360 km), genetic differentiation among the sites was low (F ST = 0.043, P < 0.0001). The Bayesian cluster analysis (STRUCTURE) indicated two probable clusters, while the non-parametric cluster analysis (AWclust) identified two to four clusters. Both analyses showed a high level of admixture within clusters. Our results indicate that blue mussels in southern Chile show lower genetic diversity than in other countries, low inbreeding levels, and limited genetic differentiation among locations.

Neisseria gonorrhoeae es una causa importante de oftalmía neonatal, pudiendo causar múltiples complicaciones en el recién nacido, incluyendo perforación corneal, panoftalmitis y ceguera. Se presenta caso de recién nacido de 1 mes de vida, con conjuntivitis infecciosa bilateral y compromiso corneal unilateral, además de cultivo positivo para gonococo. TAC mostró compromiso inflamatorio intraocular del ojo izquierdo. Se manejó con terapia antibiótica endovenosa, evolucionando con opacificación, vascularización, adelgazamiento progresivo de la córnea y atalamia del ojo izquierdo. Se sometió a cirugía para parche corneal y reformación de cámara anterior. Durante seguimiento, ecografía ocular mostró un examen normal del ojo derecho y una menor longitud axial y engrosamiento coroideo del ojo izquierdo.

Mussels are one of the most cultivated and commercialized bivalves worldwide and in southern Chile its culture represent an important economic activity. The species identification within the Mytilus genera, by morphological features, is unreliable, so we used a polymorphism RFLP in the gene encoding the polyphenolic adhesive protein as a species-specific genetic marker to describe Mytilus species diversity in southern Chile, and evaluate possible applications in traceability, food quality and safety. Using Me 15-16 marker most mussels were M. chilensis, finding no other pure individuals; however, putative hybrids of M. chilensis x M. trossulus and M. chilensis x M. galloprovincialis were detected. There was no evidence of M. edulis. The presence of the M. trossulus allele, faraway from its distribution area, demands further analysis with different genetic markers to allow a better understanding of its origin. In addition, the correspondence between markers that distinguishes northern from southern hemisphere M. galloprovincialis, with those who discriminates between M. chilensis and M. galloprovincialis would contribute to the taxonomic status of Chilean blue mussels. In Chile, the genetic composition of Mytilus indicates that geographical origin of mussels and its traceability cannot be established merely from the identification of the species. The use of other markers would be required.Los mejillones son una de las especies de bivalvos más cultivadas y comercializadas, en el sur de Chile donde su cultivo representa una actividad económica importante. La identificación de la especie dentro del género Mytilus, basada en las características morfológicas no es confiable por lo que se utilizó un polimorfismo RFLP en el gen que codifica la proteína adhesiva polifenólica como marcador genético específico de la especie para describir la diversidad de especies Mytilus en el sur de Chile, y evaluar posibles aplicaciones en trazabilidad, calidad e inocuidad de los alimentos. Usando el marcador Me 15-16, la mayoría de los mejillones fueron M. chilensis, no se encontraron individuos puros de otras especies. Sin embargo, se detectaron híbridos putativos M. chilensis x M. trossulus y M. chilensis x M. galloprovincialis. No se encontró evidencia de M. edulis. La presencia del alelo de M. trossulus, lejos de su área de distribución, requiere de análisis posteriores con diferentes marcadores genéticos para entender su origen. Además, conocer la correspondencia entre marcadores que distinguen M. galloprovincialis del hemisferio norte y sur con aquellos que discriminan entre M. chilensis y M. galloprovincialis contribuirá al estatus taxonómico del mítilido chileno. La composición genética de Mytilus en Chile no permite establecer su origen geográfico ni la trazabilidad, basándose solo en la identificación de la especie y se requiere el uso de otros marcadores.

The Chilean jack mackerel (Trachurus murphyi, Nichols, 1920) is a pelagic fish of high fishery interest, with a global capture of 828,358 mt in 2021. We report the complete mitochondrial genome of T. murphyi (Teleostei, Carangidae), collected in Bahia de Zapallar, Chile (32°33’02.59’’ S, 71°27’55.38’’ W). The size of the mitogenome is 16,561 bp (H-strand composition: 25.9% A, 16.7% C, 29.8% G, and 27.5% T). The mitogenome has the classic vertebrate gene content of 13 protein-coding, two rRNA, and 22 tRNA genes, as found in Carangidae and other Teleostei families. Phylogenetic analysis using mitochondrial genomes of 22 related species revealed that T. murphyi formed a well-supported monophyletic group with the other Trachurus species, being T. simmetricus its closest relative. Sequencing the mitochondrial genome from T. murphyi is the first step in developing traceability tools based on DNA analysis to enforce fishing quotas and trace the processed food and foodstuff containing Chilean jack mackerel following the objective of the South Pacific Regional Fisheries Management Organization (SPRFMO).

ABSTRACT We report the presence of Pristigenys serrula Gilbert 1891 off Zapallar (−32.568253, −71.464225), central Chile, during the ENSO 2023–2024 event. Morphology and a partial fragment of the mitochondrial markers cytochrome oxidase 1 (COX1) and 16S rDNA identified one specimen fished by artisanal fishermen. This report extends the known southern range limit of P. serrula by 9° of latitude (~1000 km) to central Chile (−32°) during strong negative ENSO conditions.

La pandemia del SARS-CoV-2 ha creado un desafío sin precedentes para la educación. En 2020, como resultado de las medidas para reducir la propagación del SARS-CoV-2, muchas instituciones educativas pasaron del aprendizaje presencial al aprendizaje remoto. Sin embargo, este modelo educativo puede generar estrés y ansiedad adicionales a la ansiedad provocada por la pandemia. Los objetivos del presente estudio fueron: 1) comparar las perspectivas de estudiantes y docentes sobre el número de horas dedicadas a las clases, y 2) determinar las principales dificultades que enfrentan docentes y estudiantes, respectivamente, al pasar al sistema de educación en línea. Para realizar esta investigación se realizó una encuesta online en países de habla hispana, utilizando una muestra de 1.048 participantes anónimos. A través de los datos recopilados. Se analizaron el uso de plataformas, los tipos de equipos, los niveles de angustia y las posibles razones de esta angustia. Esta pandemia es una de las amenazas de salud pública más importantes de la historia reciente y ha afectado nuestras vidas de manera significativa, siendo una de las más importantes la futura adaptación de escuelas, estudiantes y docentes a una nueva forma de aprender.

The European aquaculture industry began to undertake Atlantic halibut (Hippoglossus hippoglossus) aquaculture in the 1980s due to the favorable growth rate and high market value of this cold-water marine fish. Atlantic halibut cultivation began in Chile in 1996 in the Magallanes region (53˚S). Chilean aquaculture facilities were finally equipped to begin rearing Atlantic halibut after 12 years and a total investment of $ 2 million USD. Infrastructure is now in place to manage the entire production cycle, including broodstock rearing, egg incubation, larval rearing (yolk-sac stage, first-feeding), weaning, the nursery stage, on-growing in land-based tanks, harvest, and marketing. The hatchery phase to produce 10-g juveniles requires 10–12 months, followed by an approximately 30-month grow-out phase in land-based tanks to produce 3-kg fish. Further research and development are being performed in nutrition (diet formulation), genetics (selection for disease resistance and growth rate), fish health, and environmental issues to support the development of a sustainable marine aquaculture industry for this species.

In trout farming males exhibits lower growth rate and precocious sexual maturation in contrast to females. Since these traits are detrimental for intensive production, all females populations are most appreciated by fish farmers. Molecular markers sex-specific have been developed for rainbow trout that can be useful to diagnose the phenotypic sex of individuals. We evaluated the use of two SCAR markers (OmyP9 & Omy163), which show polymorphisms between males and females in rainbow trout as a diagnostic test for sexing farmed trout. Adult trout (n = 131) were genotyped to assess the association of the SCAR markers with phenotypic sex. To evaluate the correct performance of the SCAR marker in sex diagnosis, each marker and both were analyzed to estimate its specificity (the proportion of males that are correctly identified), sensitivity (the proportion of females that are correctly identified) and predictive value (the probability of the correct positive or negative female identification). Significant associations with phenotypic sex of both SCAR markers with sex were found. The sensitivity and predictive (positive and negative) indexes show higher values when both SCAR markers were considered (95.7, 77.4 and 94.4%, respectively). For joined SCAR markers a likelihood ratio (LR+) of 3.43 was obtained indicating its utility to establish a diagnostic test for sexing trout by use of marker-based analysis.En el cultivo de truchas los individuos del sexo masculino presentan menor tasa de crecimiento y maduración sexual precoz, características que no presentan las hembras. Debido a estos rasgos indeseables para el cultivo intensivo, el uso de poblaciones todo hembra es una práctica habitual en el cultivo de truchas. Para trucha arcoíris se han desarrollado marcadores moleculares sexo específico que pueden utilizarse en el diagnóstico temprano del sexo, en condiciones de cultivo. Se evaluó la aplicación de dos marcadores SCAR (OmyP9 y Omy163), que muestran polimorfismos entre los sexos en esta especie. Con ambos marcadores se genotipificaron 131 truchas para evaluar su asociación con el sexo fenotípico. Para determinar la utilidad en diagnóstico del sexo de cada marcador SCAR por separado, y en conjunto, se determinó la especificidad, sensibilidad y valores predictivos en la detección de un individuo de sexo femenino. Se comprobó la asociación significativa descrita para ambos SCAR con el sexo fenotípico. La mayor sensibilidad y valores predictivos positivo y negativo se obtuvo usando ambos marcadores simultáneamente (95,7; 77,4 y 94,4%; respectivamente). El valor de razón de verosimilitud (LR+ =3,43) mostró que la mejor prueba de diagnóstico para detectar hembras es usar conjuntamente OmyP9 y Omy163.

Spawning time in salmonids is a sex-limited quantitative trait that can be modified by selection. In rainbow trout (Oncorhynchus mykiss), various quantitative trait loci (QTL) that affect the expression of this trait have been discovered. In this study, we describe four microsatellite loci associated with two possible spawning time QTL regions in coho salmon (Oncorhynchus kisutch). The four loci were identified in females from two populations (early and late spawners) produced by divergent selection from the same base population. Three of the loci (OmyFGT34TUF, One2ASC and One19ASC) that were strongly associated with spawning time in coho salmon (p < 0.0002) were previously associated with QTL for the same trait in rainbow trout; a fourth loci (Oki10) with a suggestive association (p = 0.00035) mapped 10 cM from locus OmyFGT34TUF in rainbow trout. The changes in allelic frequency observed after three generations of selection were greater than expected because of genetic drift. This work shows that comparing information from closely-related species is a valid strategy for identifying QTLs for marker-assisted selection in species whose genomes are poorly characterized or lack a saturated genetic map.

The rainbow trout is a salmonid fish that occasionally exhibits broodstocks with biannual spawning behavior, a phenomenon known as a double annual reproductive cycle (DARC). Spawning time quantitative trait loci (SPT-QTLs) affect the time of the year that female rainbow trout spawn and may influence expression of the DARC trait. In this study, microsatellite markers linked and unlinked to SPT-QTLs were genotyped to investigate the underlying genetics of this trait. SPT-QTLs influenced the DARC trait since in two case-control comparisons three linked markers (OmyFGT12TUF, One3ASC and One19ASC) had significant levels of allelic frequency differentiation and marker-character association. Furthermore, alleles of One3ASC and One19ASC had significantly higher frequencies in populations that carried the DARC trait.

This study assessed the relative contributions of host genetics and diet in shaping the gut microbiota of rainbow trout. Full sibling fish from four unrelated families, each consisting of individuals derived from the mating of one male and one female belonging to a breeding program, were fed diets containing either vegetable proteins or vegetable oils for two months in comparison to a control diet consisting of only fish protein and fish oil. Two parallel approaches were applied on the same samples: transcriptionally active bacterial populations were examined based on RNA analysis and were compared with bacterial populations obtained from DNA analysis. Comparison of temporal temperature gradient gel electrophoresis (TTGE) profiles from DNA and RNA showed important differences, indicating that active bacterial populations were better described by RNA analysis. Results showed that some bacterial groups were significantly (P

This study compares the gonadosomatic index (GSI), oocyte growth (OG), gonadal histology, and plasma level concentrations of sex hormones (estradiol-17β (E2) and vitellogenin (V)) of twice-spawning (T-SP) and once-spawning (O-SP) females of rainbow trout throughout the additional and the normal reproductive cycle, respectively. In T-SP, the GSI values rapidly increase from May to November, in contrast to O-SP, which showed low and constant GSI values (1.19 to 14.5 and 1.19 to 0.63, resp.). T-SP exhibited a marked increase of OG in the same period, reaching a maximum diameter of 4,900 ± 141.42 μm, in contrast to O-SP, which presented a slow OG. The gonadal histology of T-SP agreed with the general pattern of ovogenesis observed for O-SP (vitellogenesis, ovulation, and recrudescence); however, this process was nonsynchronous between the two breeder groups. Plasma steroid levels showed significant variation during oogenesis, which agreed with the GSI, OG, and gonadal histology patterns. The level of E2 increased to a maximum value of 26.2 ng/mL and 36.0 ng/mL in O-SP and T-SP, respectively, one or two months before the spawning event where vitellogenesis was fully active. The V concentrations followed a pattern similar to those of E2.