Fernando Vega-Villasante

Este estudio presenta un análisis cienciométrico integral de la producción científica sobre Ambystoma mexicanum (ajolote), con el objetivo de comprender la evolución, estructura y dinámica de la investigación en torno a este organismo modelo. Mediante un enfoque descriptivo y longitudinal, se analizaron 1450 artículos y revisiones indexados en Scopus (1963–2024), a partir de una estrategia de búsqueda restrictiva en el campo título para asegurar la relevancia temática. Se emplearon indicadores bibliométricos y técnicas de mapeo científico para evaluar tendencias de publicación, autores, países, instituciones y evolución temática. Los resultados muestran un patrón de publicación no lineal, con un pico entre 1976–1983, una disminución a inicios de los años 2000 y un repunte posterior a 2008, posiblemente asociado con avances en genómica, medicina regenerativa y el aumento del interés en conservación tras su clasificación como especie en peligro crítico. Estados Unidos lidera la producción científica, seguido de países europeos, mientras que México presenta una participación limitada pese a ser el país de origen de la especie. El análisis temático evidencia una transición desde la embriología e histología clásicas hacia la biología molecular, la genética y, recientemente, estudios de conservación y enfoques socioambientales. Estos resultados evidencian desigualdades estructurales en la producción científica global y muestran cómo factores tecnológicos, económicos y sociales influyen en las prioridades de investigación. El estudio destaca el valor de la cienciometría para comprender el desarrollo histórico y los cambios en las prioridades de investigación sobre A. mexicanum, proporcionando una base cuantitativa para identificar tendencias de investigación y áreas que podrían requerir estudios adicionales.

Wastewater discharges pose a significant risk to aquatic ecosystems due to the complex mixtures of contaminants they contain. Although the toxicity of individual contaminants is well documented, knowledge regarding the interactions among contaminants in wastewater mixtures remains limited. Zebrafish (Danio rerio) are a well-established biological model due to their genetic similarity to humans, transparent embryonic development, and sensitivity to pollutants, making them suitable for assessing wastewater toxicity. This systematic review followed PRISMA guidelines and analyzed studies published between 2015 and 2025 in Scopus and Scielo. A total of 615 articles were screened, and 52 met all inclusion criteria. Most studies focused on treated wastewater (n = 31), followed by raw wastewater (n = 17), and frequently evaluated the embryonic stage (n = 37). Industrial, domestic, and hospital wastewater were the most common sources. The predominant toxicological outcomes included acute toxicity and teratogenesis, although reproductive, genotoxic, oxidative, and behavioral effects were also reported. Pharmaceuticals and potentially toxic elements were the most frequently measured contaminants, whereas groups such as flame retardants, pesticides, and polycyclic aromatic hydrocarbons were rarely addressed. The reviewed studies indicate that exposure to some raw and treated wastewater samples can induce adverse effects on zebrafish development, particularly during early life stages. Major gaps include limited evaluation of larval and adult stages, underrepresentation of certain wastewater sources, and insufficient characterization of complex contaminant mixtures. Addressing these gaps is essential to strengthen environmental risk assessment and protect aquatic ecosystems.

Este libro es más que un manual; más bien, es un llamado a la reflexión sobre el papel de la ciencia en la protección de las especies en peligro de extinción. En cada página, el rigor académico y la urgencia de actuar se entrelazan, recordándonos que conservar el ajolote no se trata solo de preservar una especie, sino también de salvaguardar una parte invaluable del patrimonio natural y cultural de México.

Objective: This study presents a bibliometric analysis of scientific publications on Macrobrachium acanthurus, aiming to identify strengths and weaknesses in the development of research on this species. Design/methodology/approach: One hundred scientific articles were retrieved from the Scopus database to identify the most relevant authors, institutions, countries, journals, and subject areas. The records were refined and standardized to avoid duplication, and a descriptive analysis was conducted using frequency and percentage distribution. Additionally, VOSviewer software was used to construct co-authorship, keyword co-occurrence, and international collaboration network maps. Results: In terms of individual productivity, the authors Bertini, Hernández-Hernández, and Freire lead in number of publications. The journals with the highest number of articles were the Latin American Journal of Aquatic Research and Crustaceana. The thematic analysis identified five main areas: reproduction and development, conservation and sustainable aquaculture, genetics and molecular biology, nutrition and feed; and biotechnology and applications. VOSviewer maps confirmed the existence of consolidated collaboration clusters, although with some groups remained isolated, and highlighted the centrality of Brazil and Mexico in international networks. Limitations on study/implications: The analysis was limited to the Scopus database; therefore, variations may arise if other databases are included. Findings/conclusions: The results indicate that research is primarily concentrated in Brazil and Mexico. The University of São Paulo, São Paulo State University, the Federal University of Paraná, the National Autonomous University of Mexico, and the University of Guadalajara emerge as the leading academic institutions. This study provides an integrated overview of the dynamics, gaps and research opportunities related to Macrobrachium acanthurus, offering valuable insights to guide scientific agendas, foster collaboration strategies, and support the acquaculture development of native species.

The larviculture of the Mexican axolotl (Ambystoma mexicanum) requires feeding strategies that ensure consistent survival and growth during the early stages, when digestive ontogeny, palatability, and nutrient availability determine the success of rearing. This study evaluated the effect of different live diets on the growth and survival of axolotl larvae reared under controlled conditions, with emphasis on feed acceptance and zootechnical performance. Commonly used live prey in ornamental and support aquaculture (Artemia franciscana nauplii, cladocerans, and ostracods) were compared, and performance variables (intake, weight and length gain, and survival) were recorded throughout the experimental period. Results show that the axolotl consistently accepts and efficiently utilizes A. franciscana, whereas diets containing Daphnia magna exhibit low acceptance and poorer growth performance; ostracods were an intermediate or complementary option depending on the developmental stage and prey size. Overall, the findings support the use of A. franciscana as a primary live food during the initial stages and suggest a planned transition toward larger prey as development progresses.

El presente trabajo tuvo como objetivo analizar los efectos antropogénicos en las poblaciones de langostinos nativos a través de evidencia documental. Para ello, se llevó a cabo el análisis de documentos detectados en bases de datos que abordaran los factores antropogénicos sobre estas especies. Además, se llevó a cabo la realización de encuestas a habitantes locales para recopilar información sobre el aprovechamiento de la especie y los efectos antropogénicos identificados por las comunidades. Adicionalmente, se llevó a cabo el análisis de la calidad nutricional del músculo de Macrobrachium tenellum mediante cómputo químico para determinar su calidad proteica basada en aminoácidos esenciales. La investigación identificó seis factores principales que amenazan las poblaciones de M. tenellum: modificación y fragmentación del hábitat, contaminación del agua por actividades agrícolas, industriales y urbanas, prácticas de pesca destructivas, introducción de especies invasoras, impactos del cambio climático y alteraciones en el microbioma intestinal. El análisis nutricional demostró que la proteína de M. tenellum es de alta calidad, con cantidades adecuadas de aminoácidos esenciales. Se evidencia la necesidad de implementar un enfoque de conservación holístico que integre medidas de protección ambiental, manejo sostenible y consideraciones socioeconómicas para garantizar la preservación de la especie y el bienestar de las comunidades dependientes.

The effectiveness of an artificial bait made from jackfruit flour (Artocarpus heterophyllus) in capturing freshwater crustaceans by pot fishing was evaluated, comparing it with a traditional coconut paste bait. Experimental trials were conducted with Cherax quadricarinatus, Macrobrachium tenellum, and Procambarus clarkii in controlled ponds. The results indicated that, for M. tenellum, the jackfruit flour bait was more effective than the coconut paste bait, showing significant differences. For C. quadricarinatus and P. clarkii, no statistical differences were found in the number of organisms captured between the two baits. These findings suggest that jackfruit flour could be a viable and sustainable alternative bait in crustacean fisheries, reducing the dependence on animal-based baits. Further research under natural conditions is recommended to optimize its formulation and evaluate its impact on species selectivity.

The relationship between environmental variables and the phytoplankton community in the dry season in Bahía de Banderas (BB) was analyzed. Sampling was conducted on the north (NC) and south (SC) coasts of the bay in February 2022. Physicochemical variables, nutrients, and pigments of surface and bottom water were measured, and the phytoplankton community structure was studied. The results showed that the highest temperatures were recorded in NC (23.84 ± 8.65°C). The coldest in SC (20.39 ± 2.26°C), salinity (34.06 ± 0.09), and density (24.08 ± 0.82 kg m-3) were highest in SC, while pH, dissolved oxygen, and its saturation and transparency were higher in NC; furthermore, the highest concentrations of nutrients and pigments were recorded in SC, except chlorophyll-a which was in NC. A total of 214 phytoplankton species were identified: 88 diatoms, 113 dinoflagellates, 6 silicoflagellates, 2 cyanobacteria, and 1 species for ebriids, haptophytes, euglenophytes, chlorophytes, and ciliates, highlighting the presence of 74 harmful species. Likewise, 83 species were new records for the bay. High cell abundances were recorded in SC (980,440 cells L-1) while in NC was 353,160 cells L-1. The diatoms Guinardia striata and Leptocylindrus danicus presented high abundances in the bay with 281,360 and 137,460 cells L-1, and the dinoflagellates Scrippsiella acuminata and Karenia mikimotoi with 80,380 and 55,400 cells L-1, respectively. The environmental variables temperature, salinity, depth, transparency, NH4+, NO2-, SiO2-, and pigments such as chlorophyll-a and chlorophyll-c recorded in this study explained 96.3% of the correlation with the abundance of the phytoplankton community, evidencing the sensitivity of the community to the hydrographic variability that occurs in the BB during the dry season.

The spotted sleeper (Eleotris picta), a native fish of the tropical eastern Pacific, shows a promising nutritional profile for its potential use in aquaculture. This study evaluated its bromatological composition, including meat-to-bone ratio, protein, fat, carbohydrate, ash content, as well as amino acid and fatty acid profiles. A carcass yield of 88.4 ± 1.2% and fillet yield of 23.1 ± 12.6% were obtained, values comparable to those of commercial species such as Oreochromis niloticus, Oncorhynchus mykiss, and Ictalurus punctatus. On a dry matter basis, the fillet contained 77.1 ± 18.2% protein and 2.3 ± 1.3% lipids. Lysine content reached 13.3 ± 5.2%, surpassing that of other freshwater species. Additionally, the lipid profile showed 10.4 ± 0.3% fatty acids, with high levels of EPA and DHA. These results support the potential of E. picta as a valuable alternative for the diversification of freshwater aquaculture species.

Starvation is a common process in many fishes, which rely on their energy reserves to cope. The Pacific fat sleeper (Dormitator latifrons) is an amphidromous fish distributed in the Eastern Pacific, found in marine and freshwater environments, and can tolerate wide ranges of temperatures and low oxygen levels. The present research studied the biochemical and physiological effects of different starvation and refeeding periods on fat sleeper juveniles and focused on understanding the use of energy reserves and health status. During starvation, the fat sleeper uses lipid reserves in the liver and mesentery fat as the primary energy source, but by the fourth week, an increase in serum protein and glucose levels suggests the use of muscle protein and initiation of mesentery fat as the primary energy source, using muscle protein and initiation of gluconeogenesis to maintain a glucose balance, indicating a metabolic shift towards long-term starvation. Intestinal morphology indices were affected by four starvation weeks; however, they showed a clear recovery by the end of the refeeding period. Albumin concentration was reduced after starvation, and globulin concentration increased, compromising fish health; nevertheless, normal levels at the end of the refeeding period were registered, while white blood cells did not recover normal values after four weeks of refeeding. Despite the partial compensatory growth observed, D. latifrons still prefer to use lipid sources during the initial three weeks of starvation without compromising their health. However, after four weeks, there is a switch to protein muscular use to cope with long-term starvation, which may compromise its health. Hence, D. latifrons show a high capacity to maintain homeostasis and restore their biochemical and physiological status.