Adição de OptiLisina® à dieta de juvenis do axolote Ambystoma velasci para o seu crescimento e sobrevivência

The axolotl Ambystoma velasci is an endemic amphibian of Mexico, due to different environmental and anthropogenic pressures the wild populations have decreased, for which it is listed in NOM-059-SEMARNAT-2010 as a species subject to special protection. An important aspect for their well-being, development, and adaptation in captivity is offering a varied diet; however, there are no studies on the nutritional requirements of this genus of salamanders. In captivity, one of the favorite foods of this amphibian is the mudworm Tubifex spp., but live food does not always cover the nutritional requirements, therefore, strategies are sought to improve the quality of the food, one of them is its enrichment, incorporating supplements, such is the case of the OptiLisina® formula, which is an herbal supplement characterized by being a source of lysine, which when added to the diet has a positive influence as a growth promoter. The objective of this study was to evaluate the parameters of growth, food consumption and survival with the addition of OptiLisina® to the diet of A. velasci juveniles under captive conditions. The experimental design consisted of a trial with 120 individuals of 110 days of age distributed in three levels of OptiLisina® (0, 0.5 and 1.0 g/kg) added to the Tubifex spp., with four repetitions each. The growth in weight and height was recorded to calculate the productive parameters and to be analyzed in a Completely Random Design using orthogonal linear and quadratic polynomials to evaluate the effect of the herbal supplement (P<0.05) in the Software, R. The results of the diet did not show linear or quadratic effects on productive parameters (P> 0.05). More studies are needed on the nutritional requirements of this amphibian, in order to carry out better feeding strategies for the species and favor its maintenance in captivity.El ajolote Ambystoma velasci es un anfibio endémico de México, debido a las presiones ambientales y antropogénicas sus poblaciones silvestres han disminuido, por lo cual se encuentra enlistado como especie sujeta a protección especial (NOM-059-SEMARNAT-2010). Un aspecto importante para su bienestar, desarrollo y adaptación en cautiverio es ofrecer una dieta variada; sin embargo, no existen estudios acerca de los requerimientos nutricionales en este género de salamandras. En cautiverio, uno de los alimentos de predilección de este anfibio es el gusano de fango Tubifex spp., aunque no siempre el alimento vivo cubre los requerimientos nutricionales, por ende, se buscan estrategias para mejorar la calidad del alimento, una de ellas es su enriquecimiento, incorporando suplementos, tal es el caso de la fórmula OptiLisina® que es un complemento herbal que se caracteriza por ser fuente de lisina, que adicionado a la dieta influye positivamente como promotor de crecimiento. El objetivo del presente estudio fue evaluar los parámetros de crecimiento, consumo de alimento y supervivencia con la adición de OptiLisina® a la dieta de juveniles de A. velasci en condiciones de cautiverio. El diseño experimental  consistió en un ensayo con 120 individuos de 110 días de edad distribuidos en tres niveles de OptiLisina® (0, 0,5 y 1,0 g/kg) adicionado al Tubifex spp., con cuatro repeticiones cada uno. Se registró el crecimiento en peso y talla para calcular los parámetros productivos y ser analizados en un Diseño Completamente al Azar empleando polinomios lineales y cuadráticos ortogonales para evaluar el efecto del complemento herbal (P<0.05) en el Software, R. Los resultados de la dieta no mostraron efectos lineales ni cuadráticos en los parámetros productivos (P> 0,05). Se necesitan realizar más estudios sobre los requerimientos nutricionales de este anfibio, para así realizar mejores estrategias de alimentación para la especie y favorecer su mantenimiento en cautiverio.O axolote Ambystoma velasci é um anfíbio endêmico do México, devido a diferentes pressões ambientais e antrópicas as populações selvagens diminuíram, pelo que está listado no NOM-059-SEMARNAT-2010 como uma espécie sujeita a proteção especial. Um aspecto importante para seu bem-estar, desenvolvimento e adaptação em cativeiro é oferecer uma dieta variada, porém não existem estudos sobre as exigências nutricionais desse gênero de salamandras. Em cativeiro, um dos alimentos preferidos deste anfíbio é a minhoca Tubifex spp., porém a alimentação viva nem sempre cobre as exigências nutricionais, por isso, buscam-se estratégias para melhorar a qualidade da alimentação, uma delas é o seu enriquecimento, incorporando suplementos, como é o caso da fórmula OptiLisina®, que é um suplemento fitoterápico caracterizado por ser fonte de lisina, que quando adicionado à dieta tem influência positiva como promotor de crescimento. O objetivo deste estudo foi avaliar os parâmetros de crescimento, consumo alimentar e sobrevivência com a adição de OptiLisina® à dieta de juvenis de A. velasci em cativeiro. O delineamento experimental consistiu em um ensaio com 120 indivíduos de 110 dias de idade distribuídos em três níveis de OptiLisina® (0, 0,5 e 1,0 g/kg) adicionado ao Tubifex spp., com quatro repetições cada. O crescimento em peso e altura foi registrado para calcular os parâmetros produtivos e para ser analisado em um Projeto Completamente Aleatório usando polinômios ortogonais lineares e quadráticos para avaliar o efeito do suplemento de ervas (P<0,05) no Software, R. Os resultados de a dieta não apresentou efeitos lineares ou quadráticos nos parâmetros produtivos (P>0,05). Mais estudos são necessários sobre as exigências nutricionais deste anfíbio, a fim de realizar melhores estratégias alimentares para a espécie e favorecer sua manutenção em cativeiro

Caracterización molecular de bacterias rizosféricas asociadas a Echinocactus platyacanthus en invernadero y silvestres

The sweet biznaga (Echinocactus platyacanthus) is an endemic cactusof Mexico characterized by its slow growth and low rate of reproduction, which together with a high collection pressure, places wild populations at risk. Currently, the study of bacterial communities associated with cactusis scarce and it is unknown whatcultivable bacteria are present in the rhizosphere of sweet biznagas that grow in nature and those that are grown in nurseries. For this study rhizospheric material was collected from wild and cultivated biznagas, in addition to non-rhizospheric soil. A total of 268 morphotypes were isolated and grouped into 41 different ribotypes by RFLP. Representatives of each ribotype were identified by sequencing the 16S rRNA gene. The cultivable fraction of the bacterial community associated with E. platyacanthusis mainly composed of members of the genera Bacillus(21 strains), Pseudomonas(6 strains), Stenotrophomonas(4 strains), Paenibacillus(2 strains), Brevibacterium, Staphylococcusand Cutibacterium(1strain,each one), with Bacillusgenus being the predominant. The genera Bacillusand Pseudomonashave been previously reported for carrying out beneficial activities for the plants with which they are associated.La biznaga dulce (Echinocactus platyacanthus) es una cactácea endémica de México caracterizada por su lento crecimiento y baja tasa de reproducción, lo que aunado a una alta presión de recolecta, coloca a las poblaciones silvestres en una situación de riesgo. Actualmente, el estudio de las comunidades bacterianas asociadas a cactáceas es escaso y se desconoce qué bacterias cultivables están presentes en la rizósfera de las biznagas dulces que crecen en la naturaleza y en las que se cultivan en viveros. Para este estudio se recolectó material rizosférico de biznagas silvestres y cultivadas, además de suelo no rizosférico. Se aislaron en total de 268 morfotipos y se agruparon en 41 ribotipos diferentes por RFLP. Representantes de cada ribotipo se identificaron mediante la secuenciación del gen 16S rRNA. La fracción cultivable de la comunidad bacteriana asociada con E. platyacanthus está compuesta principalmente por miembros de los géneros Bacillus (21 cepas), Pseudomonas (seis cepas), Stenotrophomonas (cuatro cepas), Paenibacillus (dos cepas), Brevibacterium, Staphylococcus y Cutibacterium (una cepa, cada una), siendo Bacillus el género predominante. Los géneros Bacillus y Pseudomonas han sido reportados previamente por llevar a cabo actividades beneficiosas para las plantas a las que están asociados

Comprehensive Analysis of Gut Microbiota Composition and Functional Metabolism in Children with Autism Spectrum Disorder and Neurotypical Children: Implications for Sex-Based Differences and Metabolic Dysregulation

This study aimed to investigate the gut microbiota composition in children with autism spectrum disorder (ASD) compared to neurotypical (NT) children, with a focus on identifying potential differences in gut bacteria between these groups. The microbiota was analyzed through the massive sequencing of region V3–V4 of the 16S RNA gene, utilizing DNA extracted from stool samples of participants. Our findings revealed no significant differences in the dominant bacterial phyla (Firmicutes, Bacteroidota, Actinobacteria, Proteobacteria, Verrucomicrobiota) between the ASD and NT groups. However, at the genus level, notable disparities were observed in the abundance of Blautia, Prevotella, Clostridium XI, and Clostridium XVIII, all of which have been previously associated with ASD. Furthermore, a sex-based analysis unveiled additional discrepancies in gut microbiota composition. Specifically, three genera (Megamonas, Oscilibacter, Acidaminococcus) exhibited variations between male and female groups in both ASD and NT cohorts. Particularly noteworthy was the exclusive presence of Megamonas in females with ASD. Analysis of predicted metabolic pathways suggested an enrichment of pathways related to amine and polyamine degradation, as well as amino acid degradation in the ASD group. Conversely, pathways implicated in carbohydrate biosynthesis, degradation, and fermentation were found to be underrepresented. Despite the limitations of our study, including a relatively small sample size (30 ASD and 31 NT children) and the utilization of predicted metabolic pathways derived from 16S RNA gene analysis rather than metagenome sequencing, our findings contribute to the growing body of evidence suggesting a potential association between gut microbiota composition and ASD. Future research endeavors should focus on validating these findings with larger sample sizes and exploring the functional significance of these microbial differences in ASD. Additionally, there is a critical need for further investigations to elucidate sex differences in gut microbiota composition and their potential implications for ASD pathology and treatment

DYNAMICS OF HYPERBOLIC IWIPS

Abstract. We present two proofs of the fact, originally due to Reiner Martin [26], that any fully irreducible hyperbolic element of Out(FN) acts on the projectivized space of geodesic currents PCurr(FN) with uni-form north-south dynamics. The first proof, using purely train-track methods, provides an elaborated and corrected version of Reiner Martin’s original approach. The second proof uses the geometric intersection form of Kapovich and Lustig and relies on unique ergodicity results from symbolic dynamics. 1

Genomic characteristics of <i>Salmonella</i> Montevideo and Pomona: impact of isolation source on antibiotic resistance, virulence and metabolic capacity

Salmonella enterica is known for its disease-causing serotypes, including Montevideo and Pomona. These serotypes have been found in various environments, including river water, sediments, food, and animals. However, the global spread of these serotypes has increased, leading to many reported infections and outbreaks. The goal of this study was the genomic analysis of 48 strains of S. Montevideo and S. Pomona isolated from different sources, including clinical. Results showed that environmental strains carried more antibiotic resistance genes than the clinical strains, such as genes for resistance to aminoglycosides, chloramphenicol, and sulfonamides. Additionally, the type 4 secretion system, was only found in environmental strains. .Also many phosphotransferase transport systems were identified and the presence of genes for the alternative pathway Entner-Doudoroff. The origin of isolation may have a significant impact on the ability of Salmonella isolates to adapt and survive in different environments, leading to genomic flexibility and a selection advantage.</p