Nicholls State University

About: Nicholls State University is a education organization based out in Thibodaux, Louisiana, United States. It is known for research contribution in the topics: Population & The Internet. The organization has 456 authors who have published 795 publications receiving 20031 citations.

Effect of Freshwater Acclimation on the Swimming Performance and Plasma Osmolarity of the Euryhaline Gulf Killifish

Abstract: The objective of this research was to determine the effect of freshwater acclimation on the swimming performance and plasma osmolarity of gulf killifish Fundulus grandis. Fish were acclimated to either freshwater or brackish water (10‰ salinity) for 10 d before experimentation. Plasma osmolarity was significantly lower in the freshwater-acclimated fish; however, no significant changes occurred in plasma osmolarity in fish recovering from a swim challenge at either salinity. Critical swimming speeds of the fish acclimated to freshwater were significantly lower than those of fish acclimated to brackish water. Furthermore, the swimming challenge caused 40% mortality in the freshwater fish but no mortality in the brackish-water fish. Acclimation of gulf killifish to freshwater environments appears to have a substantial metabolic cost.

The bowfin genome illuminates the developmental evolution of ray-finned fishes.

Abstract: The bowfin (Amia calva) is a ray-finned fish that possesses a unique suite of ancestral and derived phenotypes, which are key to understanding vertebrate evolution. The phylogenetic position of bowfin as a representative of neopterygian fishes, its archetypical body plan and its unduplicated and slowly evolving genome make bowfin a central species for the genomic exploration of ray-finned fishes. Here we present a chromosome-level genome assembly for bowfin that enables gene-order analyses, settling long-debated neopterygian phylogenetic relationships. We examine chromatin accessibility and gene expression through bowfin development to investigate the evolution of immune, scale, respiratory and fin skeletal systems and identify hundreds of gene-regulatory loci conserved across vertebrates. These resources connect developmental evolution among bony fishes, further highlighting the bowfin's importance for illuminating vertebrate biology and diversity in the genomic era.

Use of formic acid to control vibriosis in shrimp aquaculture

Abstract: Luminous vibriosis is a shrimp disease that causes major economic losses in shrimp industry as a result of massive shrimp kills due to bacterial infection caused by Vibrio species. Use of antibiotics to control Vibrio in shrimp aquaculture is not allowed in the United States and so it is necessary to develop an alternative pathogen control method for shrimp production. Short-chain fatty acids have been used as food preservatives for a long time. Organic acids are commonly added in feeds in animal production, such as chicken, pig, and cattle. In this study, growth inhibition effects of formic acid on five selected Vibrio species, namely Vibrio alginolyticus, Vibrio cholerae, Vibrio harveyi, Vibrio parahaemolyticus and Vibrio vulnificus were studied. The Vibrio bacteria were grown on both solid and liquid media using Muller-Hinton agar and alkaline peptone water, respectively, with various concentrations of formic acid. Bacterial growth was monitored in the liquid media using optical density method. The results showed significant inhibition of growth of all five Vibrio species by formic acid at low concentration. The effective concentration (EC50) values were calculated for all five Vibrio species, which were less than 0.039% of formic acid. The results are encouraging to supplement formic acid in the shrimp feed as a control mechanism to reduce Vibrio outbreak in shrimp aquaculture system.