Search

The article focuses on the detection of ostreid herpesvirus 1 (OsHV-1) infection that caused mortality in Crassostrea gigas or Pacific oyster cultures in California since 1993. It states that the infection was confirmed using the transmission electron microscopy, sequence analysis and the polymerase chain reaction (PCR). It notes that observing the new DNA strain of OsHV-1 in healthy C. gigas is found by conducting a prospective sampling before implementing surveillance monitoring.

In recent years, the shrimp industry has turned to inland freshwater culture as one method to avoid problems such as the introduction of possible vectors of viral pathogens into seawater ponds. Our experiments evaluated susceptibility to white spot syndrome virus (WSSV) in Litopenaeus vannamei held under different salinity regimens. Juvenile L. vannamei that were conditioned at salinities of 35, 25, 15, 5 and 2 g L−1 were challenged with WSSV. In order to assess the severity of white spot disease, histological analysis and nested polymerase chain reaction (PCR) tests were carried out on the challenged shrimp every 4 h after 48 h post challenge. The results indicated that significantly more severe infections resulted at 15‰ than at other salinities. Mortality could not be compared due to the sampling design and because severe WSSV infections occurred in all test groups such that few shrimp remained alive in each challenged group at the end of the test. Despite this, the results suggest that salinity may affect the course and outcome of WSSV infections. [ABSTRACT FROM AUTHOR]

Cynoscion parvipinnis is an important fisheries resource of the Gulf of California used locally for human consumption. Its aquaculture potential has recently been demonstrated, and cultured organisms are already available. In this study, the gonadal developmental stage, proximate composition, fatty acid profile and other biochemical and biological indices of wild and cultured fish were characterized. A total of 80 fish, 30 cultured (15 female and 15 male) and 50 wild (31 female and 19 male), captured in November at Santa Rosa, Sonora, Mexico, were analyzed. Histological analyses of the gonads showed that 100% of the wild and cultured fish were at an early maturation stage. Wild fish had greater body weight, total length and gonadosomatic index. Cultured female fish (19.64%) possessed a slightly higher protein content in their gonads than wild females (17.11%), whereas males had similar values (14.00 and 14.83%). Cultured females (10.85%) and males (20.48%) had a significantly greater crude fat content than wild fish (female: 2.05%, male: 11.05%). Palmitic acid was the most abundant fatty acid (FA), ranging from 128.58-164.84 mg of 16:0 g-1 of gonad wet weight. After 16:0, highly unsaturated FAs like DHA, ARA and EPA were the major FA in gonadal tissue; n-3 FAs were quantitatively higher than n-6 FAs, while the n-3/n-6 ratios ranged from 2.08-2.81. In general, the biochemical composition of the gonad of wild and cultured organisms at an early maturation stage was quite similar. These data may serve as indicators of dietary requirements for a maturation diet for broodstock culture.

Prohibitin (PHB) is a highly conserved eukaryotic protein complex involved in multiple cellular processes. In insects, PHB has been identified as a potential target protein to insecticidal molecules acting as a receptor of PF2 insecticidal lectin in the midgut of Zabrotes subfasciatus larvae (bean pest) and Cry protein of Bacillus thuringiensis in Leptinotarsa decemlineata (Colorado potato beetle). This study aimed to characterize the structural features of Z. subfasciatus prohibitin (ZsPHB) by homology modeling and evaluate its expression and tissue localization at different stages of larval development both at the transcript and protein levels. The samples were collected from eggs and larvae of different developmental stages. The immunodetection of ZsPHB was done with anti-PHB1 and confirmed by LC-MS/MS analysis. Gene expression analysis of ZsPHB1 and ZsPHB2 was performed by RT-qPCR, and immunohistochemistry with FITC-labeled anti-PHB1. Results showed that ZsPHBs exhibit distinctive characteristics of the SPFH protein superfamily. The transcript levels suggest a coordinated expression of ZsPHB1 and ZsPHB2 genes, while ZsPHB1 was detected in soluble protein extracts depending on the stage of development. Histological examination showed ZsPHB1 is present in all larval tissues, with an intense fluorescence signal observed at the gut. These results suggest a physiologically important role of PHB during Z. subfasciatus development and show its regulation occurs at the transcriptional and post-transcriptional levels. This is the first characterization of PHB in Z. subfasciatus., (Copyright © 2022 Elsevier Inc. All rights reserved.)

The Ostreid herpes virus type 1 (OsHV-1) is one of the most devastating pathogen in oyster cultures. Among several factors, as food limitation, oxygen depletion, salinity and temperature variations, episodes of "summer mortality" of the Pacific oyster Crassostrea gigas have also been associated with OsHV-1 infection. Mortalities of C. gigas spat and juveniles have increased significantly in Europe, and contemporary mortality records of this mollusk in México have been associated with the occurrence of OsHV-1. In the present study, the expression of the heat shock protein 70 gene from the Pacific oyster correlates with the abundance of DNA polymerase transcripts from the OsHV-1. This may suggest that the induction on the expression of the Pacific oyster hsp70 may potentially participate in the immune response against the virus. Furthermore, this study reports for the first time a TEM representative image of the OsHV-1 in aqueous solution, which possesses an icosahedral shape with a diameter of 70 nm × 100 nm. Finally, the examined sequence encoding the ORF4 of the OsHV-1 isolate from northwest Mexico showed specific sequence variations when compared with OsHV-1 isolates from distant geographical areas., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

The HSP70 proteins are an important element of the response against thermal stress and infectious diseases, and they are highly conserved and ubiquitous. In some species, variations on the hsp70 encoding sequence resulted in intraspecific differential expression, which leads to variations on thermo-tolerance among individuals. This phenomenon has not been described in the Pacific oyster Crassostrea gigas, which is cultivated in Mexico under temperature conditions highly above the optimal for this species. The present study was aimed to identify associations between hsp70 genotypes and their expression levels in C. gigas. By analyzing a 603 bp fragment from the 3' end of the hsp70 gene, 21 different genotypes with 60 nucleotide polymorphic sites were detected, of which 34 sites were found in heterozygous condition. Although no correlation was found between genotype-expression-season, a minimum expression threshold that should be taken into account as an important feature for a future breeding program is proposed., (Copyright © 2015 Elsevier Ltd. All rights reserved.)

To detect the presence of point mutations in a small section of the mutS homolog2 (MSH2) gene in both healthy and affected persons treated at the General Hospital of the State of Sonora, a 353 base pair section of the MSH2 gene was amplified and sequenced from six persons affected by hereditary nonpolyposis colorectal cancer and from 19 healthy persons. The affected persons did not show the mutations reported in the scientific literature; however, six healthy persons were heterozygote and mutant-allele carriers. The heterozygote condition implies that carriers are candidates for the development of colorectal cancer. However, it is important to know the family medical history when investigating hereditary mutations.

White shrimps, Litopenaeus vannamei, were tested in two indoor trials to determine the effect of fumonisin B1 on (i) immune response, (ii) histopathology, and, (iii) muscle proteins. Trial 1: (0, 0.5, 0.75 and 1.0μg/g of FB1 levels, 18-day duration; shrimp 5-6g) to evaluate the FB1 effect on the immune system and histopathology response. Trial 2: (0.0, 0.5, 0.75 and 1.0μg/g of FB1 levels, 16-day duration; shrimp 5-6g) to detect FB1 effect on muscle proteins. Prophenoloxidase activity was affected by all FB1 concentrations tested. Both, total haemocyte count and phenoloxidase activity decreased by the 18th day in shrimp exposed to FB1. Marked histological changes in the hepatopancreas of shrimp fed on diet containing FB1, at the all FB1 levels tested, as well as a necrotic tissue were observed. Changes in both, electrophoretic patterns and thermodynamic properties of myosin extracted from shrimp exposed to FB1 were also observed., (Copyright © 2008 Elsevier Ltd. All rights reserved.)

For the shrimp farming industry of Mexico, disease outbreaks caused by white spot syndrome virus (WSSV) are relatively recent. Efforts to control the virus are assisted by monitoring for its prevalence in aquaculture systems, but few attempts have been made to search for it in carriers from coastal waters. To search for WSSV carriers in the Gulf of California, we made surveys off the coast of Sinaloa, Mexico, in March 2001, November 2001, and September 2003 using polymerase chain reaction (PCR) assays and histopathology. WSSV-positive shrimp were detected only in November 2001, after hurricane Julliete. This suggested possible dispersal of WSSV to the marine environment from infected shrimp farms.