Targeted glutamate supply boosts insulin concentrations, ovarian activity, and ovulation rate in yearling goats during the anestrous season

The neuroendocrine regulation of the seasonal reproductive axis requires the integration of internal and external signals to ensure synchronized physiological and behavioral responses. Seasonal reproductive changes contribute to intermittent production, which poses challenges for optimizing goat product yields. Consequently, a significant objective in seasonal reproduction research is to attain continuous reproduction and enhance profitability in goat farming. Glutamate plays a crucial role as a modulator in several reproductive and metabolic processes. Hence, the aim of this study was to evaluate the potential impact of exogenous glutamate administration on serum insulin concentration and ovarian function during the out-of-season period in yearling goats. During the anestrous season, animals were randomly located in individual pens to form two experimental groups: (1) glutamate (n = 10, live weight (LW) = 29.1 ± 1.02 kg, body condition score (BCS) = 3.4 ± 0.2 units) and (2) control (n = 10; LW = 29.2 ± 1.07 kg, BCS = 3.5 ± 0.2), with no differences (p < 0.05) regarding LW and BCS. Then, goats were estrus-synchronized, and blood sampling was carried out for insulin quantification. Ovaries were ultrasonographically scanned to assess ovulation rate (OR), number of antral follicles (AFs), and total ovarian activity (TOA = OR + AF). The research outcomes support our working hypothesis. Certainly, our study confirms that those yearling goats treated with exogenous glutamate displayed the largest (p < 0.05) insulin concentrations across time as well as an augmented (p < 0.05) out-of-season ovarian activity

The impact of extensive grazing in the behavior of soluble sugars in Prosopis laevigata (Humb. & Bonpl. ex Willd.) M.C.Johnst. trees

Objective: To evaluate the impact of extensive grazing in the accumulation of soluble sugars in Prosopis laevigata trees, whose leaves and fruits are directly consumed by cattle. Design/Methodology/Approach: The ejido Emiliano Zapata in Durango was the study area. Stem and root samples were collected from a stand of extensive grazing and a stand without cattle. The sampling was carried out in three growth stages: March (flowering), June (fruition), and October (leaf fall). The samples were frozen in liquid nitrogen and were lyophilized. Afterwards, they were ground and 10 mg of dry matter were weighted in microtubes. The total soluble sugars (TSS) concentration was determined following the Van Handel methodology, using a spectrophotometer at 625 nm. The statistical analysis was carried out using an ANOVA and the Tukey’s test. Results: In March, the grazing area had lower TSS concentrations during regrowth than the area without grazing, both at root and stem levels. Study Limitations/Implications: The intensity of grazing and the pasture rotation should be regulated to favor carbohydrate accumulation in trees, which is required for the formation of the meristematic tissues. Finding/Conclusions: Extensive grazing has an impact on the synthesis and accumulation of TSS in mesquite trees. Therefore, the consumption of branches, leaves, and fruits decreases TSS concentrations in the stem and the root

Near-Membrane Dynamics and Capture of TRPM8 Channels within Transient Confinement Domains

The cold and menthol receptor, TRPM8, is a non-selective cation channel expressed in a subset of peripheral neurons that is responsible for neuronal detection of environmental cold stimuli. It was previously shown that members of the transient receptor potential (TRP) family of ion channels are translocated toward the plasma membrane (PM) in response to agonist stimulation. Because the spatial and temporal dynamics of cold receptor cell-surface residence may determine neuronal activity, we hypothesized that the movement of TRPM8 to and from the PM might be a regulated process. Single particle tracking (SPT) is a useful tool for probing the organization and dynamics of protein constituents in the plasma membrane.We used SPT to study the receptor dynamics and describe membrane/near-membrane behavior of particles containing TRPM8-EGFP in transfected HEK-293T and F-11 cells. Cells were imaged using total internal reflection fluorescence (TIRF) microscopy and the 2D and 3D trajectories of TRPM8 molecules were calculated by analyzing mean-square particle displacement against time. Four characteristic types of motion were observed: stationary mode, simple Brownian diffusion, directed motion, and confined diffusion. In the absence of cold or menthol to activate the channel, most TRPM8 particles move in network covering the PM, periodically lingering for 2–8 s in confined microdomains of about 800 nm radius. Removing cholesterol with methyl-beta-cyclodextrin (MβCD) stabilizes TRPM8 motion in the PM and is correlated with larger TRPM8 current amplitude that results from an increase in the number of available channels without a change in open probability.These results reveal a novel mechanism for regulating TRPM8 channel activity, and suggest that PM dynamics may play an important role in controlling electrical activity in cold-sensitive neurons

Carbon dynamics and CO2 and CH4 exchange in the mangrove dominated Guayas river delta, Ecuador

Although estuaries are considered important pathways in the global carbon cycle, carbon dynamics in tropical estuaries is relatively understudied. Here, the tidal, seasonal and spatial variability of particulate organic carbon (POC), dissolved inorganic carbon (DIC), carbon dioxide (CO2) and methane (CH4), among other biogeochemical variables related to carbon cycling, were studied in the Guayas river delta (Ecuador) to document the sources, processing and fluxes of these carbon forms. All variables were studied during a semi-diurnal (13 hour) tidal cycle and along river transects at low and high tides, all carried out during one dry and rainy season. POC and total suspended matter (TSM) strongly covaried and peaked at high tidal flow velocities during a tidal cycle and at high river discharge during the rainy season, suggesting that resuspension of bottom sediments and/or surface erosion in the river catchment were a dominant source of particulate matter in the water column. The δ13C of POC, (from ~-22‰ to ~-27‰) showed an increasing contribution of marine phytoplankton to the POC pool as moving downstream along the delta during the dry season. Upstream DIC concentrations (~1200 μmol L-1) were high in the Guayas river delta as compared to other tropical estuarine systems, and the δ13C of DIC revealed a shift from a more phytoplankton dominated source in the dry season and downstream (~-4‰) to a relatively more terrestrial source in the rainy season and upstream (~-12.5‰). Both DIC and its δ13C showed slight but consistent deviations from conservative mixing that hint at inputs of 13C depleted DIC from mineralization along the delta. High values of the partial pressure of CO2 (pCO2) observed upstream and in the rainy season (~5250 μatm), associated with O2 undersaturation (~60%) and low δ13CDIC, suggest a strongly heterotrophic system, and resulted in high CO2 efflux to the atmosphere. CH4 concentrations were also higher during the rainy than dry season (93.5±62.5 vs. 61.3±39.5 nmol L-1), but unlike pCO2, showed tidal variations similar to TSM and POC, thus alluding to potential CH4 release from sediments during resuspension events at high tidal flow velocities. This explorative survey revealed complex drivers and biogeochemical processes acting upon various spatio-temporal scales which are necessary to consider for a complete understanding of the carbon biogeochemistry in estuarine systems. Similar surveys on estuarine carbon in data scarce regions are encouraged to constrain uncertainties in coastal zone carbon budgets

Diseño del sistema de distribución primarío de la subestación salinas de la empresa eléctrica península de Santa Elena basado en la calidad del servicio

En la actualidad, las empresas de distribución eléctrica deben encargarse no solo de llevar energía hasta sus clientes, sino también, de ofrecer un nivel aceptable de calidad de dicha energía. Esto se da porque cada vez existen más aparatos eléctricos que son sensibles a los disturbios, pero en especial, porque los entes de control exigen que se cumplan parámetros de calidad establecidos por medio de regulaciones. La interrupción del servicio eléctrico a causa de fallas en el sistema de distribución es uno de los acontecimientos más problemáticos y comunes que se presentan y que influyen directamente en la calidad del servicio. Disminuir este problema, un beneficio tanto para la empresa como para los clientes, es lo que se busca conseguir con el desarrollo de este proyecto.En este proyecto se presenta un análisis técnico-económico de la Subestación Salinas, perteneciente a la Empresa Eléctrica Península de Santa Elena (EMEPE), para el rediseño de su red primaria de distribución, tomando como principal parámetro la Calidad del Servicio. Se muestran índices probabilísticos cuyo propósito es evaluar cuan confiable es un sistema de distribución eléctrico. Estos índices tienen la habilidad de medir la frecuencia de las interrupciones y los efectos de los disturbios que se presenten en el sistema. Los índices calculados para los diferentes diseños expuestos en este proyecto, constan en regulaciones de países como Ecuador y Argentina y de organismos como la IEEE y CE

Reproductive efficiency of Ovsynch + CIDR in Holstein cows under a fixed time artificial insemination scheme in northern Mexico

Se evaluó el uso de Ovsynch más dispositivo intravaginal de liberación controlada de progesterona (CIDR) en vacas altas productoras. El estudio se llevó en la Comarca Lagunera (25° 44´ N, 103° 10´ O a 1,111 msnm) durante diciembre y enero. Las vacas (n=100) se pre-sincronizaron con dos inyecciones de PGF2α a los 35 y 47 días posparto y asignadas a dos tratamientos (n= 50): 1) El grupo OV recibió el protocolo Ovsynch: 100 μg de GnRH (i.m.; día 1), 25 mg de PGF2α (i.m.; día 7) y 100 μg GnRH (i.m.; día 9); 2) El grupo (OV+C) recibió el protocolo Ovsynch más un CIDR (1.38 g), retirado siete días después. Todas las vacas se expusieron a un protocolo de inseminación artificial a tiempo fijo (IATF; 16 a 20 h posteriores a la última inyección). Se registró tanto el porcentaje de preñez, el número de vacas repitiendo celo considerando dos periodos (≤24 y ≥25 días post-inseminación), así como los días de retorno al celo. Mientras que no existió diferencia entre grupos para tasa de preñez (OV= 28 %, OV+C= 32 %; P>0.05), el porcentaje de vacas que manifestaron celo después de la IATF difirió (P0.05), the percentage of cows showing estrus after IATF differed (P<0.05) between treatments for the two studied periods (28 % vs 62 % ≤24 d; 69 % vs 35 % ≥25 d; OV and OV+C, respectively). Moreover, mean of days when cows repeated estrus was lower (P<0.05) in the OV+C group (25 ± 1.6 vs 30 ± 1.3 d). Although the Ovsynch+CIDR treatment did not improve pregnancy rate, it reduced the latency for return to estrus, emerging as an alternative to diminish the days to the next AI, and potentially improve the reproductive efficiency and the economic return of the dairy herd