ABSTRACT. The Pacific mackerel Scomber japonicus aquaculture is receiving growing attention, and further development of this industry is expected to protect wild stocks. Information on S. japonicus hematology is very limited. Therefore, the present study aimed to provide the hematological and serum chemistry profiles associated with sex and some seasonal variations in Pacific mackerel from Todos Santos Bay, Baja California, Mexico. Fish were sampled in April (spring) and August (summer). Results showed that the condition factor and all blood parameters analyzed in male and female mackerel were not affected by sex (P > 0.05). The seasonality effect on the mackerel was observed in some blood parameters such as mean corpuscular hemoglobin, total protein, globulin, and triglycerides that exhibited lower values in April compared to August (P < 0.05). While white blood cell count was higher in August (P < 0.05) compared with April. The fish sampled during the two sampling times were possibly a heterogeneous group of ages (1 to 3 years) with lengths ranging from 20 to 30 cm. Consequently, there is an urgent need to follow doing reference interval databases to assess Pacific mackerel health status under different conditions.

Abstract Background: handgrip strength (HGS) is a health-status parameter associated with multicomorbidity in the adult population. Objective: the aim of the present study was to determine the association between HGS (i.e., absolute and relative) and abdominal obesity (AO), type-2 diabetes (T2D), and hypertension (HT), as well as to determine the association between low relative HGS with the presence of multicomorbidity (i.e., the co-occurrence of two or more comorbidities together) in a Mexican population. Methodology: a cross-sectional study was carried out in 860 participants from the south of Mexico (661 women and 199 men). The age range evaluated was from 18 to 65 years. Assessments were made of sociodemographic data, clinical history, anthropometric parameters, and measurement of maximal HGS. Results: the regression models adjusted by age show that the presence of comorbidities (i.e., AO, HT and T2D) was linked negatively to HGS (i.e., absolute and relative). Moreover, in men, a low relative HGS in both hands reported an association with the presence of three simultaneous comorbidities (right, RR: 17.2, p < 0.001; left, RR: 11.92, p = 0.020). In women the same association was found (right, RR: 10.42, p < 0.001; left, RR: 9.90, p < 0.001). Conclusion: lower levels of relative HGS were linked to the presence of simultaneous comorbidities (i.e., the joint presence of AO, T2D and HT). Furthermore, HGS (i.e., absolute and relative) presented an inverse association with individual anthropometric and clinical parameters related to cardiovascular risk in the Mexican population.

Resumen Introducción: la fuerza prensil de la mano (FPM) es un parámetro asociado con la multicomorbilidad en la población adulta. Objetivo: el objetivo del presente estudio fue determinar la asociación entre la FPM (absoluta y relativa) y la obesidad abdominal (OA), la diabetes tipo 2 (DT2) y la hipertensión (HT), así como su asociación con la multicomorbilidad (co-occurrencia de dos o más comorbilidades conjuntas) en una población mexicana. Metodología: se presenta un estudio transversal realizado en 860 participantes del sur de México (661 mujeres y 199 hombres). El rango de edad de los participantes fue de 18 a 65 años. Se evaluaron las características sociodemográficas de la población, los parámetros clínicos y antropométricos, y la medición de la FPM máxima. Resultados: los resultados demostraron una asociación entre la disminución de la FPM (absoluta y relativa) y la presencia de comorbilidades (OA, DT2 e HT). En los hombres, la disminución de la FPM relativa reportada en ambas manos se asoció con la presencia simultánea de tres comorbilidades (derecha, RR: 17,2, p < 0,001; izquierda, RR: 11,92, p = 0,020). Se observó una asociación similar también en las mujeres (derecha, RR: 10,42, p < 0,001; izquierda, RR: 9,90, p < 0,001). Conclusión: los bajos niveles de FPM relativa se asocian con la presencia simultánea de comorbilidades (presencia conjunta de OA, DT2 y HT). Además, la FPM (absoluta y relativa) se relaciona negativamente con los parámetros clínicos y antropométricos relacionados con el riesgo cardiovascular en la población mexicana.

ABSTRACT Optimal function of the immune system allows the recognition and elimination of infected and tumor cells. However, these cells can develop mechanisms to evade the cellular immune response. In human papillomavirus (HPV) infection, dysregulation of major histocompatibility complex Class I molecules and other components of the innate immune system promote the survival of infected cells by allowing the infection to persist which, in turn, favors the development of cancer. Further, tumor cells possess inherent mechanisms designed to block the recognition and activation of cytotoxic lymphocytes: particularly, HPV proteins such as E1 and E2 and oncoproteins E5, E6, and E7 that inhibit immune mechanisms and/or stimulate the expression of immunosuppressive cytokines. These mechanisms include a decrease in receptor activation and costimulating molecules on the surface of immune cells, as well as the constitutive expression of molecules that inhibit their function, which allow HPV persistence and tumor progression. Immunotherapy-based therapeutic options are positioned as excellent candidates for the treatment of cervical cancer.

ABSTRACT Dormitator latifrons is an amphidromous fish species distributed on the Pacific coastal region from California to Peru. It has a high potential to be cultured in Mexico. However, there is very little information about its biology, physiology and culture. This research study is a contribution to the hematology and blood chemistry of this native species. Results show hematocrit values of 28%, erythrocytes 2.075×106 mm3, leukocytes 35.035×103 mm3, mean corpuscular volume 161.547 fL, NBT 0.39, glucose 51.467 mg dL−1, protein 3.936 g dL−1, albumin 1.906 g dL−1, globulin 2.391 g dL−1 and albumin/globulin ratio 0.686.

Abstract Purpose: Based on the literature, conceptual aspects of innovations in teaching practices were identified in order to understand and reflect on the transcendence of the formative processes, and confirm the achievement of teaching competences. Methodology: A documentary review was conducted to identify concepts about innovation and transformation of educational practices, as well as the possible impact of teacher training and certification on the quality of learning. Main results: Innovation in teaching implies adopting different ways of working by incorporating new components into the teacher’s practice, and the papers analyzed show that there is a clear tendency to incorporate ICT as an innovative element. Likewise, a permanent transformation of these practices can only be achieved through reflection and performance evaluation processes, provided that feedback is taken into account. Discussion: Present and future educational demands require the training of teachers to use tools of the digital age and transform their practice, which is possible only through thorough reflection that allows teachers to consolidate their methodologies and reinforce their own learning. Teaching performance evaluation should focus on the teacher’s actual performance, retrieving valuable information about their performance and at the same time providing feedback to promote reflection. No studies were found that relate the effectiveness in the results of learning linked to teacher certification.

Resumen Propósito: A partir de la revisión de la literatura, se identifican aspectos conceptuales de las innovaciones de la práctica docente, que han permitido comprender y reflexionar sobre la transcendencia de los procesos formativos y de convalidación del logro de las competencias docentes. Metodología: Se realizó una revisión documental para identificar conceptos sobre la innovación y transformación de las prácticas educativas, así como los posibles efectos de la formación y la certificación docente en la calidad del aprendizaje. Principales resultados: La innovación docente implica que los profesores adopten una forma distinta de trabajo mediante la incorporación de nuevos elementos a su práctica, y los trabajos analizados indican que existe clara tendencia a incorporar la TIC como elemento innovador. Asimismo, la transformación permanente de estas prácticas es posible mediante la reflexión y los procesos de evaluación del desempeño, siempre y cuando se considere la retroalimentación. Discusión: Las demandas educativas actuales y futuras exigen el dominio de competencias de los profesores para utilizar herramientas de la era digital y transformar su práctica, lo cual es posible a través de procesos reflexivos, que permiten al docente consolidar sus metodologías y fortalecer su propio aprendizaje; la evaluación del desempeño docente debe centrarse en el desempeño del profesor, que posibilite la recuperación de información valiosa sobre su actuación así como obtener retroalimentación para promover la reflexión. No se encontraron trabajos que relacionen la efectividad en los resultados de aprendizaje ligados a la certificación docente.

ABSTRACT The present study evaluated the growth performance and whole-body composition of the hybrid red tilapia (Oreochromis mossambicus × O. aureus) raised in saltwater and fed three experimental diets containing different protein levels (25.6, 30.8 and 35.6% CP; crude protein). The hybrid red tilapia showed a high production performance across all dietary treatments: specific growth rate (SGR) = 3.12-3.51% body weight d-1; weight gain = 391-503%; feed conversion ratio (FCR) = 0.90-1.07; thermal growth coefficient (TGC) = 1.50-1.67; condition factor (CF) = 0.19-0.26. Dietary protein content significantly affected feed intake; fish fed the 30.8% CP diets displayed higher feed intake than those fed the 25.6% CP diet. Although the protein efficiency ratio (PER) was not significantly affected by dietary treatments, fish fed 25.6% CP diet demonstrated numerically higher values than those fed the other dietary treatments (4.34 vs. 3.06-3.35). The viscerosomatic index was significantly reduced in the 25.6% CP group compared to 30.8 and 35.6% CP groups. Regarding the whole-body composition, dietary protein affected all parameters, except lipid content. Fish fed the 30.8% CP diet exhibited significantly reduced relative protein content and elevated ash content in the whole-body in comparison to other dietary groups. The results of the present study indicated that juveniles of hybrid red tilapia accepted all dietary treatments. However, according to polynomial regression analyses based on PER and the high ash content in tilapias fed the 30.8% CP, it is suggested that the optimum dietary protein content for juvenile hybrid red tilapia was 25.6%.

ABSTRACT Fish mariculture from the genus Seriola spp. can present high mortalities due to parasites. In Mexico, the mortality yellowtail Seriola dorsalis caused by parasites is low, and there are no reports of massive mortality events. However, as the aquaculture activity of yellowtail intensifies, parasites will be increasingly conspicuous. Therefore, the present study is an aim to know S. dorsalis’s susceptibility to a monogenean infection mixed under RAS experimental conditions and their intensity and spatial distribution on the skin and gills. In this study, a parasitic mix induction was performed using two monogenean species such as Zeuxapta seriolae and Benedenia seriolae besides the Amyloodinium ocellatum, a dinoflagellate that was naturally presented. At the end of the experiment after 45 days, B. seriolae prevalence was 100% with a mean intensity of 122 parasites and showed a preference for the head and body of the fish. Zeuxapta seriolae prevalence was 100% with a mean intensity of 40 parasites preferentially found in the second branchial arch. In the case of A. ocellatum prevalence was of 100% with a mean intensity greater than 200 trophozoites per fish. The fish mortality reached 90% at the end of the experiment. During the infection, the fish weight decreased a 14% at the end of the experiment. Therefore, it will be necessary to carry out prophylactic and control strategies, to reduce the impact of these parasites under culture conditions.

ABSTRACT: An 18-week feeding trial was conducted to estimate the optimum dietary pantothenic acid (PA) requirement for juvenile of Lutjanus guttatus. Seven isoproteic and isocaloric practical diets were formulated containing graded levels of pantothenic acid (PA) 2.57, 31.97, 47.91, 63.79, 76.83, 103.15 and 121.91 mg kg-1. Triplicate groups of 15 fish, with an initial weight of 10.2 ± 1.4 g, were cultured in 21 glass-fiber tanks and received each diet at random three times daily to apparent satiety. Results showed that the weight gain of fish fed diet 2.57 mg kg-1 PA was significantly less than the weight gain of fish fed diets containing greater quantities of PA. However, no significant differences were observed in the weight gain of the fish fed diets containing between 31.97 to 121.91 mg kg-1 PA. External signs of deficiency in the fish of diet (2.57 mg kg-1 PA) included caudal fin erosion, desquamation of the skin, hemorrhages in the body and fins, lethargy and 80% mortality rate were recorded. Hematological parameters indicated that there was no clear reduction of hemoglobin with PA in the diets. The dietary PA requirement to attain maximum growth rate, good survival, and the absence of external injuries range between 40.10 and 44.29 mg kg-1.

ABSTRACT: Some studies have characterized and evaluated the parasitic load of the Pacific sardine. However, there are few studies related to its physiology and parasites load. This study aimed to evaluate the blood parameters and the abundance of helminth parasites of sardines obtained from two samples from Todos Santos Bay during autumn 2013. The digenea Myosaccium ecaude parasite was the only species registered. Sardines had a prevalence of 28%, an average abundance of 25 and an intensity of 7 parasites. There were no statistically significant differences (P > 0.05) in most of the analyzed blood parameters (red blood cell count, hematocrit, leukocyte cellular differentiation, mean corpuscular volume, total protein, glucose, alanine aminotransferase, osmotic pressure, Na, K, and pH) of fish with and without parasites, except in white blood cell count and in Ca concentration that showed a marked decrease. The relationship between parasite abundance and blood parameters, based on the results of this study, it is not clear due to the low parasitic load.

Abstract Background: Different methods are currently used for the prevention and control of diseases in aquaculture. Prophylaxis with immunostimulants from microscopic fungi provides protection against diseases and increases resistance to parasites. In this context, Basidiomycota fungi could have high potential for use in aquaculture because they contain different compounds, such as fungal proteins, polysaccharides, terpenoids, vitamins, and minerals, which could work as immunostimulants. Goals: Collect and disseminate the information on species of macroscopic fungi that have been used as immu nostimulants in the farming of teleost fish and the fungi that have not been tested in fish but have shown positive results in other organisms. Methods: We gather, discuss and compare the experimental, scientific and theoretical literature related to the immunostimulant effect of macroscopic fungi in the cultivation of teleosts, as well as fungi whose stimulating effect has been positive in other organisms. Results: We evaluated more than 50 species of fungi with immunostimulating properties. Nevertheless, in recent years, the effects of only eight species of macromycetes, belonging to the genera Ganoderma, Inonotus, Lentinula, Pleurotus, and Trametes, have been evaluated in 17 published papers regarding the immune response of nine species of fish. Seven of these papers are about isolated glucans, six about crude and alcoholic extracts, two about pulverized basidiomata, and one about a mushroom fermented by-product. Conclusions: Due to the limited information on the immunostimulating effect of macromycetes on fish, more research is needed regarding other fungi species with immunostimulant properties, the correct determination of fungi species, their culture, and in vivo and in vitro tests that confirm their immune system effects on the model organism and target organism.

Resumen Antecedentes: Actualmente se utilizan diferentes métodos para la prevención y control de enfermedades en la acuicultura. La profilaxis con inmunoestimulantes a partir de hongos macroscópicos proporciona protección ante enfermedades y aumenta la resistencia a parásitos. En este contexto, los hongos Basidiomycota podrían tener un alto potencial para su uso acuícola, ya que contienen diferentes compuestos, como proteínas fúngicas, polisacáridos, terpenoides, vitaminas y minerales, que podrían tener un efecto inmunoestimulante. Objetivos: Analizar la información existente relativa a las especies de hongos macroscópicos que han sido evaluadas como inmunoestimulantes en el cultivo de peces teleósteos y también la de aquéllos que no han sido probados en peces pero que han mostrado resultados positivos en la respuesta inmune en otros organismos. Métodos: Se reunió, expuso y comparó la literatura experimental, científica y teórica relacionada con el efecto inmunoestimulante de los hongos macroscópicos en el cultivo de teleósteos así como la relativa a hongos cuyo efecto estimulante ha sido positivo en otros organismos. Resultados: Actualmente se han comprobado las propiedades inmunoestimulantes de más de 50 especies de hongos macroscópicos. No obstante, en 17 investigaciones publicadas durante los últimos años sólo se ha evaluado el efecto sobre la respuesta inmune de nueve especies de peces ante ocho especies de hongos: Ganoderma, Inonotus, Lentinula, Pleurotus, Phellinus y Trametes. De dichas publicaciones, siete consisten en la evaluación de glucanos purificados, seis de extractos crudos o alcohólicos, dos de basidiomas pulverizados y uno de un subproducto de hongo fermentado. Conclusiones: Debido a la escasa información existente sobre el efecto inmunoestimulante de macromicetes en peces, es preciso llevar a cabo más investigaciones que aborden su potencial en otras especies, que se estudie su cultivo y su correcta determinación, y se realicen pruebas in vitro e in vivo, tanto del organismo modelo como de organismos blanco, para confirmar sus efectos sobre el sistema inmune.

Resumen Introducción: El síndrome metabólico (SM) es un problema de salud pública, el cual no cuenta con estrategias adecuadas de prevención, diagnóstico y tratamiento para población infantil. Los criterios existentes son controversiales y no son aplicables en los niños. Asimismo, varían según autores y comités de expertos; lo que podría tener importantes consecuencias en el diagnóstico de SM, impactando el tratamiento oportuno y el pronóstico del individuo. Objetivo: Validar criterios (NCEP-ATPIII; Cook, Ford y Duncan, et al; Ferranti, et al; Cruz, et al; e IDF1) para el diagnóstico de SM en niños mexicanos. Metodología: Estudio transversal de 2599 niños entre 6 y 16 años, residentes de la Ciudad de México. Se consideró SM con tres o más de los cinco componentes en los distintos criterios; y dos o más componentes con la presencia de obesidad central para IDF. Se consideró como Gold Standard la combinación de los cinco criterios diagnósticos. Para identificar el mejor valor predictivo se calculó sensibilidad, especificidad, valor predictivo positivo (VPP), valor predictivo negativo (VPN) y razón de verosimilitud. Resultados: Se observó una mayor proporción de individuos diagnosticados con SM con el criterio de Ferranti, et al. en comparación con los demás criterios evaluados. Nuestra propuesta ad hoc presentó una alta sensibilidad (0,89) y especificidad (0,90) frente al Gold Standard aplicado. Conclusión: El criterio propuesto por nosotros contiene una elección de componentes sencillos y de bajo costo, que facilitará su aplicación, permitiendo la unificación en el diagnóstico, tratamiento y pronóstico poblacional, reduciendo los índices de morbimortalidad en mexicanos.

Abstract Introduction: Metabolic syndrome (MS) is a public health problem without appropriate strategies for prevention, diagnosis and treatment in children. Existing criteria are controversial and not applicable for pediatric population, with variations according to different authors and expert committees, which could have important consequences in MS diagnosis, treatment and prognosis. Objective: To validate different definitions (NCEP-ATPIII; Cook, Ford and Duncan, et al; Ferranti, et al; Cruz, et al; and IDF1) for metabolic syndrome diagnosis in Mexican children. Methodology: Cross-sectional study of 2599 children aged between 6 and 16 years, residents of Mexico City. MS was defined as the presence of three or more of the five components in the different criteria; and two or more components with the presence of central obesity for IDF. The Gold Standard was considered as the combination of the five diagnostic criteria. To identify the best predictive value, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and likelihood ratio were calculated. Results: A greater proportion of individuals diagnosed with the Ferranti, et al criterion was observed in comparison with the other criteria evaluated. We proposed an ad hoc criteria which showed a high sensitivity (0,89) and specificity (0,90) compared to the Gold Standard applied. Conclusion: Our diagnostic criteria contains a choice of simple and low-cost components that will facilitate its application in health institutions and will unify-diagnostic criteria, treatment, and prognosis, reducing morbidity and mortality rates in Mexican population.

Abstract: Objective: To investigate the correlation among pro- or anti-inflammatory cytokines and the two main gut microbiota phyla in obese children. Materials and methods: Anthropometric data were obtained from 890 children under 14 years old to determine the degree of obesity. Serum cytokine concentration was measured by ELISA. Relative abundance of gut microbiota in feces was evaluated by quantitative Real-Time PCR assays. Results: Anthropometric and biochemical parameters were statistically higher in overweight /obese children than in lean ones. Increased TNF-α levels were found in obese children that also have a high relative abundance of Firmicutes. Conclusions: Obese children have a high relative abundance of Firmicutes that correlates with increased levels of TNF-α. This is the first study that shows a relation between Firmicute abundance and TNF-α serum concentration in obese children.

Resumen: Objetivo: Investigar la correlación entre las citocinas proinflamatorias o antiinflamatorias y los dos principales filos de la microbiota intestinal en niños obesos. Material y métodos: Se obtuvieron mediciones antropométricas de 890 niños de 6 a 14 años; posteriormente se clasificaron en normopeso y sobrepeso/obeso. Las concentraciones séricas fueron medidas por el método de ELISA. La abundancia relativa de la microbiota intestinal en heces se evaluó por PCR tiempo real. Resultados: Los parámetros bioquímicos y antropométricos fueron estadísticamente más altos en niños con sobrepeso / obesidad que en niños delgados. Se encontraron niveles más altos de FNT-α en niños obesos que también tenían una abundancia relativa alta de Firmicutes. Conclusiones: Los niños obesos tienen una alta abundancia relativa de Firmicutes, la cual se correlaciona con un incremento de los niveles de FNT-α. Este es el primer estudio que evalúa la reacción entre la abundancia de Firmicutes y la concentración sérica de FNT-α en niños obesos.

Abstract: Objective: To investigate the correlation among pro- or anti-inflammatory cytokines and the two main gut microbiota phyla in obese children. Materials and methods: Anthropometric data were obtained from 890 children under 14 years old to determine the degree of obesity. Serum cytokine concentration was measured by ELISA. Relative abundance of gut microbiota in feces was evaluated by quantitative Real-Time PCR assays. Results: Anthropometric and biochemical parameters were statistically higher in overweight /obese children than in lean ones. Increased TNF-α levels were found in obese children that also have a high relative abundance of Firmicutes. Conclusions: Obese children have a high relative abundance of Firmicutes that correlates with increased levels of TNF-α. This is the first study that shows a relation between Firmicute abundance and TNF-α serum concentration in obese children.

Resumen: Objetivo: Investigar la correlación entre las citocinas proinflamatorias o antiinflamatorias y los dos principales filos de la microbiota intestinal en niños obesos. Material y métodos: Se obtuvieron mediciones antropométricas de 890 niños de 6 a 14 años; posteriormente se clasificaron en normopeso y sobrepeso/obeso. Las concentraciones séricas fueron medidas por el método de ELISA. La abundancia relativa de la microbiota intestinal en heces se evaluó por PCR tiempo real. Resultados: Los parámetros bioquímicos y antropométricos fueron estadísticamente más altos en niños con sobrepeso / obesidad que en niños delgados. Se encontraron niveles más altos de FNT-α en niños obesos que también tenían una abundancia relativa alta de Firmicutes. Conclusiones: Los niños obesos tienen una alta abundancia relativa de Firmicutes, la cual se correlaciona con un incremento de los niveles de FNT-α. Este es el primer estudio que evalúa la reacción entre la abundancia de Firmicutes y la concentración sérica de FNT-α en niños obesos.

Cryptococcus neoformans is an opportunistic pathogenic yeast that causes serious infections, most commonly of the central nervous system (CNS). C. neoformans is mainly found in the environment and acquired by inhalation. It could be metaphorically imagined that cryptococcal disease is a “journey” for the microorganism that starts in the environment, where this yeast loads its suitcase with virulence traits. C. neoformans first encounters the infected mammalian host in the lungs, a site in which it must choose the right elements from its “virulence suitcase” to survive the pulmonary immune response. However, the lung is often only the first stop in this journey, and in some individuals the fungal trip continues to the brain. To enter the brain, C. neoformans must “open” the main barrier that protects this organ, the blood brain barrier (BBB). Once in the brain, C. neoformans expresses a distinct set of protective attributes that confers a strong neurotropism and the ability to cause brain colonisation. In summary, C. neoformans is a unique fungal pathogen as shown in its ability to survive in the face of multiple stress factors and to express virulence factors that contribute to the development of disease.

Abstract Marine fish culture, both in hatchery and grow-out systems, is prone to parasitic infestations, which lead to fish health impairment and generally high mortality rates. The most frequent disease in these cultures, amyloodiniosis, is caused by the dinoflagellate Amyloodinium ocellatum, the parasite considered to inflict the most considerable damage on commercial marine fish ventures. In recent years, the yellowtail Seriola dorsalis cultured in Baja California has undergone recurrent parasitic infections. Thus, the objective of the present work was to evaluate the effects of a parasitic infection (A. ocellatum) in juvenile yellowtail in terms of mortality, gill histology, and blood parameters. Fish exposed to parasitic infection exhibited 100% prevalence, with mean intensity of 766 ± 500 parasites per fish (grand mean ± SD). Gill histological analyses indicated damage characterized by inflammation, epithelial detachment, hyperplasia, fusion of secondary lamellae, telangiectasia, and proliferation of mucous cells. Regarding blood parameters, red blood cell count, mean corpuscular hemoglobin concentration, and hemoglobin, glucose, and triglyceride concentrations were significantly higher (P < 0.05) in infected fish (parasite prevalence of 100% with a mean intensity of 882.19 ± 265.05 parasites per fish) than in healthy ones. Also, mean corpuscular volume, total protein, albumin, and globulin were significantly lower (P < 0.05) in infected fish than in healthy fish. No differences were found in the hematocrit, mean corpuscular hemoglobin, and white blood cell count (P > 0.05). This study demonstrated that A. ocellatum infection caused severe gill damage, affecting gas exchange efficiency, which resulted in blood parameter changes and, consequently, high mortality rates in a short-term period.

Resumen El cultivo de peces marinos, tanto en el criadero como en el cultivo para engorda, es vulnerable a la incidencia de parásitos, lo que afecta la salud de los peces y, en general, conduce a altas tasas de mortalidad. La enfermedad más frecuente en estos cultivos, la amiloodiniosis, es causada por el dinoflagelado Amyloodinium ocellatum, considerado el parásito que inflige el daño más considerable a las empresas comerciales de peces marinos. En los últimos años, el jurel Seriola dorsalis cultivado en Baja California ha padecido infestaciones parasitarias recurrentes. Por lo tanto, el objetivo del presente trabajo fue evaluar los efectos de una infestación parasitaria (A. ocellatum) en juveniles de jurel en términos de mortalidad, histología de las branquias y parámetros sanguíneos. Los peces expuestos a la infestación parasitaria exhibieron una prevalencia del 100% con una intensidad media de 766 ± 500 parásitos por pez (gran promedio ± desviación estándar). El análisis histológico de las branquias indicó daño caracterizado por inflamación, desprendimiento epitelial, hiperplasia, fusión de las lamelas secundarias, telangiectasia y proliferación de células del mucus. Con respecto a los parámetros sanguíneos, el recuento de glóbulos rojos, la concentración de la hemoglobina corpuscular media, y las concentraciones de hemoglobina, glucosa y triglicéridos fueron significativamente mayores (P < 0.05) en peces infestados (prevalencia parasitaria del 100% con una intensidad media de 882.19 ± 265.05 parásitos por pez) que en peces sanos. Además, el volumen corpuscular medio, la proteína total, la albúmina y la globulina fueron significativamente más bajos (P < 0.05) en los peces infestados que en los peces sanos. No se encontraron diferencias en el hematocrito, la hemoglobina corpuscular media y los recuentos de glóbulos blancos (P > 0.05). Este estudio demostró que la infestación por A. ocellatum causó daños severos en las branquias que afectaron la eficiencia del intercambio de gases, lo que resultó en cambios en los parámetros sanguíneos y, en consecuencia, altas tasas de mortalidad en un corto periodo de tiempo.