Leydy Sandoval-Vargas

• PhD EN CIENCAS AGROPECUARIAS
• University of the Llanos

To meet growing fish demand, aquaculture must develop sustainable, cost‐effective, and high‐performance fish feed formulations for industry advancement. Plant‐based lipids are a viable alternative to forage fish ingredients in finfish diets. However, most plant‐derived lipids lack long‐chain polyunsaturated fatty acids (LC‐PUFA) like EPA and DHA, w...

The chorion is an acellular envelope that surrounds fish oocytes and embryos, playing a crucial role in protection against environmental factors until hatching. In salmonids, several chorion malformations have been documented, including white-spotted (disc-like) chorion. This study focused on investigating the ultrastructural modifications of the c...

Simple Summary Galaxias maculatus plays an important ecological and socioeconomic role in Chile. We determine the sex ratio, sexual maturity stages, gonadosomatic index, spawning period, type and frequency of spawning, and fecundity under experimental culture. The sex ratio was close to 1:1. First sexual maturity was reached at one year of age in 5...

Rapid environmental changes will be the major challenge that most biota will have to deal with in the near future. Extreme events, such as marine heatwaves, are becoming more frequent and could be spatially uniform at a regional scale for a relatively long period of time. To date, most research studies on heatwaves have focused on sessile organisms...

To date, little attention has been paid to identifying the effects of long-term cryopreservation on sperm quality for Piaractus orinoquensis. The object of this study was therefore to evaluate the effect of long-term cryopreser-vation (24 h, 1, 6 and 12 months) on sperm motility, viability, DNA integrity, ATP content, total antioxidant capacity (TA...

Fish sperm quality assessment is an essential process for commercial production. The goal of this study was to evaluate the quality of fresh milt of farmed coho salmon using a functional and structural approach. A total of 37 males were used to determined parameters such as sperm concentration, pH and osmolality of seminal plasma, viability, mitoch...

In the present study, we examined three permeating cryoprotectant agents (CPAs) and two freezing systems for the cryopreservation of coporo spermatozoa. Milt samples of 5 males were diluted with cryoprotectant solutions containing 10% Me2SO, 10% MeOH and 8% DMA, respectively, with or without hen egg yolk. Half of the 0.25‐ml straws were frozen in a...

Sperm cryopreservation is an important tool for reproductive management; however, it has not been possible to perform this procedure for coho salmon. This study was designed to assess the effect of cryopreservation on sperm functional parameters, oxidative stress markers and fertilizing capacity of coho salmon. Eight extenders were tested, consisti...

Calcium is a prerequisite factor for triggering the sperm activation in salmonids. The aim of this study was to test different concentrations of Ca²⁺ on sperm motility activation and fertility of rainbow trout (Oncorhynchus mykiss). Semen samples activated with calcium free activator (0.0 mM) and increasing concentrations of CaCl2 (6.3, 7.9, 9.5 an...

Reactive oxygen species (ROS) have been proposed as one of the main causes of the impairment of fish spermatozoa integrity and functionality during cryopreservation. The high content of unsaturated fatty acids in sperm cells and the low antioxidant capacity of diluted semen are key factors in making sperm cells susceptible to ROS attacks. For this...

Short-term storage of semen is a necessary key procedure in fish; it allows maximizing the use of gametes. Nevertheless, sperm quality decreases during storage has been associated with oxidative stress damage due to an increase in reactive oxygen species (ROS) during storage. This study was designed to optimize a short-term storage protocol for Coh...

Variables de calidad seminal en cachama blanca (Piaractus brachypomus): relación con la viabilidad posdescongelación. Resumen Introducción: La cachama blanca (Piaractus brachypomus), es la especie nativa más representativa de la piscicultura nacional. Se han desarrollado técnicas que han permitido la crioconservación de sus gametos, observándose va...