Tag Donald V. Lightner

Un estudio analiza muestras de camarones infectados con microsporidios en Madagascar, Mozambique y Arabia Saudita, y con signos clínicos de enfermedad de algodón del camarón. 

Study analyzes samples of microsporidia-infected shrimp in Madagascar, Mozambique and Saudi Arabia and with clinical signs of cotton shrimp disease. 

Authors examined the histological features from shrimp infected with the emerging microsporidian parasite Enterocytozoon hepatopenaei (EHP). A PCR assay method was used to detected in hepatopancreatic tissue, feces and water sampled from infected shrimp tanks, and in some samples of Artemia biomass. 

In analyzing the plasmid sequence from the whole genome sequences of AHPND V. parahaemolyticus (V.p) isolates, researchers identified a clear geographical variation within the plasmid, and developed PCR methods to characterize AHPND V.p isolates as either Mexico-type or Southeast Asia-type. 

A laboratory study at the University of Arizona examined the effects of tilapia to control EMS and mortality in Pacific white shrimp.in controlling AHPN. 

Studies by the University of Arizona Aquaculture Pathology Laboratory identified the causative agent for AHPNS as a unique strain of Vibrio parahaemolyticus bacteria that can produce toxins responsible for the primary pathology in affected shrimp. 

Since Taura syndrome virus was in the Americas when yellow head virus become pandemic in Asia, it is possible TSV prevented shrimp in the Western Hemisphere from infection by materials from Asia containing YHV. To test this idea, the authors evaluated the viral interactions in shrimp preinfected with TSV and then challenged with YHV. 

To determine origins of White Spot Syndrome Virus and Taura Syndrome Virus in Saudi Arabia, authors performed genotyping studies and found a new genotype in each of the isolates collected. 

Early Mortality Syndrome is a new disease that has been detected at shrimp farms in Asia. It appears within 30 days of stocking and causes symptoms that include lethargy; soft, darkened shells and mottling of the carapace. 

An in situ hybridization procedure can be used to diagnose blue crabs from Chesapeake Bay infected with a reovirus. 

In a challenge test under controlled conditions using a severe strain of the virus, resistance to WSSV was shown in shrimp supplied by the Camaronera de Coclé, S.A. L. vannamei genetics program. 

The University of Arizona’s Aquaculture Pathology Laboratory oversees ring tests for a group of shrimp diagnostic laboratories in 10 countries. 

Basic components of biosecurity include knowledge of diseases, adequate detection methods and the use of “clean” shrimp stocks. 

A rapid PCR assay for detection of WSSV was based on the nested, two-step PCR procedure recommended in the Manual of Diagnostic Tests for Aquatic Animals. 

In an NHP (necrotizing hepatopancreatitis) challenge test, shrimp from a Colombian breeding program had higher resistance and 30 percent greater survival than a control line of Taura syndrome virus-free shrimp.