José Cuauhtémoc Ibarra-Gámez

Virus de la necrosis hipodérmica y hematopoyética infecciosa (IHHNV) y virus del síndrome de Taura (TSV) en camarón silvestre (Farfantepenaeus aztecus Ives, 1891 y Litopenaeus setiferus Linnaeus, 1767) de La Laguna Madre, Golfo de México

Se reporta la presencia del virus de la necrosis hipodermica y hematopoyetica infecciosa (IHHNV) y del virus del sindrome de Taura (TSV) en camarones silvestres Litopenaeus setiferus (camaron blanco) y Farfantepenaeus aztecus (camaron cafe) capturados en el estero de La Pesca, en La Laguna Madre, Tamaulipas, Mexico. El estudio se realizo por histopatologia y amplificacion de acidos nucleicos. La prevalencia de TSV fue 6,6% (12/180) y 4,4% para IHHNV (8/180). La mayoria de los casos se presentaron de noviembre a marzo (15/180). La presencia de estos virus en camarones silvestres de La Laguna Madre, alerta sobre el riesgo en que se encuentran las poblaciones silvestres y las granjas camaroneras colindantes con el Golfo de Mexico, por lo que se sugiere establecer un programa de monitoreo sanitario y verificar el impacto de ambos virus en camarones de granjas vecinas a La Laguna Madre.

Draft Genome Sequence of White Spot Syndrome Virus Isolated from Cultured Litopenaeus vannamei in Mexico

ABSTRACT The first genome sequence of a Mexican white spot syndrome virus is presented here. White spot syndrome is a shrimp pandemic virus that has devastated production in Mexico for more than 10 years. The availability of this genome will greatly aid epidemiological studies worldwide, contributing to the molecular diagnostic and disease prevention in shrimp farming.

Growth and metabolic responses of whiteleg shrimp Litopenaeus vannamei and Nile tilapia Oreochromis niloticus in polyculture fed with potential probiotic microorganisms on different schedules

ABSTRACT. Probiotics and co-culture of shrimp and tilapia are two strategies to improve yield and eco-efficiency of both species. However, only few studies have analyzed the combination of these two strategies. This study analyzes the effect of a mixture of potential probiotics supplied in the diet at different frequencies in a system of shrimp (10 m -2 ) and tilapia (5 m -2 ) in a trial lasting 84 days. The probiotics mixture was composed of four lactic acid bacteria and one yeast strain that were supplied either daily, every 5 days, or every 10 days in the diet and compared with a control without any supply of probiotics. At the end of the experiment, blood chemistry and hematology of shrimp and tilapia were analyzed as an index of physiological condition. Water quality did not differ between treatments. The final weight, feed conversion ratio, and yield of shrimp were significantly higher with daily supply of probiotics compared to shrimp that did not receive probiotics supply, with intermediate values for treatments with probiotics supply every 5 or 10 days. However, level of supplementation every 5 days could be considered as optimal because no significant differences with daily supply were observed for any variable, whereas the supply each 10 days resulted in a significantly lower yield. Significantly higher final weight, feed conversion ratio, and yield of tilapia occurred with daily supplements. Blood cholesterol in tilapia significantly decreased with increasing frequency of probiotics supplementation. These results indicate that probiotics supplements for shrimp and tilapia cultivated simultaneously improved yields and physiological condition.

Draft Genome Sequence of Pseudoalteromonas piscicida Strain 36Y RITHPW, an Hypersaline Seawater Isolate from the South Coast of Sonora, Mexico

OBJECTIVES This study reports the draft genome sequence of Pseudoalteromonas piscicida strain 36Y_RITHPW, a marine Gammaproteobacteria that synthesises bioactive compounds with antagonistic activity against Vibrio parahaemolyticus, a multidrug-resistant strain that is the causative agent of acute hepatopancreatic necrosis disease (AHPND), reported in shrimp farm outbreaks from Asia to Mexico with mortality rates of 80-100%. METHODS The genome of P. piscicida 36Y_RITHPW was sequenced with an Ion Torrent™ Personal Genome Machine™ (PGM) platform. A total of 606805 reads were constructed for a 308.48Mbp and 33.5×coverage. A high-quality draft assembly and ordering of contigs was obtained with Mauve. The annotation was obtained with RAST and antiSMASH. RESULTS The genome size consists of 5.15Mbp, with a total of 4548 genes, 4217 protein-coding sequences and a GC content of 43.3%. Several resistance genes as well as other genes involved in the production of bacteriocins and ribosomally synthesised antibacterial peptides are also present. CONCLUSIONS Mining of this draft genome provides valuable information to explain the antagonistic capacity of P. piscicida 36Y_RITHPW, a useful strain as a potential probiotic in shrimp aquaculture against pathogenic V. parahaemolyticus.