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In this study the enrichment dietary effect with different crude protein levels (CP) and feed additives on growth, survival, feed conversion ratio (FCR), feed consumption (FC) and total hemocyte count (THC) in juvenile white shrimp Litopenaeus vannamei were evaluated. The study covered two bioassays: in the first one, juveniles were daily fed for 45 days with four experimental diets containing: (1) Control, commercial feed (35% CP); (2) 29% CP; (3) 32% CP; (4) 35% CP. After the 29% CP diet was selected, juveniles in bioassay II were daily fed for 45 days with a single CP diet complemented with probiotics: (1) Control, commercial feed (35% CP); (2) 29% CP; (3) 29% CP + Bacillus mix at 1×106 CFUg-1 feed; and (4) 29% CP + yeast mix at 1×106 CFUg-1 feed. Juvenile shrimp fed with experimental diets gained significantly more weight and increased survival, FCR, FC and THC compared with control diet. However, differences among experimental diets were not significant. In bioassay II, juvenile shrimp fed with experimental diet + feed additives significantly increased survival, FCR, FC and THC compared with control diet. Growth of juveniles significantly increased with 29% CP and 29% CP + yeast mix diets, compared with control group. Complementing the diet with yeast mix showed higher survival and THC of juveniles compared with the other experimental treatments. Different CP levels in shrimp diet improved growth, survival and circulating hemocytes, and addition of mixed yeast as feed additive induced better survival and immune response in juvenile shrimp., Resumen: En este estudio se evaluó el efecto del enriquecimiento de dietas con diferentes niveles de proteína cruda (CP) y aditivos en el crecimiento, supervivencia, tasa de conversión alimenticia (FCR), consumo de alimento (FC) y conteo total de hemocitos (THC) en juveniles de camarón blanco Litopenaeus vannamei. El estudio consta de dos bioensayos: en el primero, los juveniles fueron alimentados diariamente por 45 días con cuatro dietas experimentales con diferente contenido de proteína: (1) Alimento comercial o control, CP 35%; (2) CP 29%; (3) CP 32%; (4) CP 35%. Después de seleccionar CP 29%, en el bioensayo II los juveniles fueron alimentados diariamente por 45 días con una dieta proteica complementada con probióticos: (1) Alimento comercial o control, CP 35%; (2) CP 29%; (3) CP 29% + mezcla de Bacillus a 1×106 UFCg-1 alimento; y (4) CP 29% + mezcla de levaduras a 1×106 UFCg-1 alimento. Los camarones juveniles alimentados con las dietas experimentales mostraron ganancia en peso significativamente mayor e incremento en supervivencia, FCR, FC y THC comparado con la dieta control. Sin embargo, no hubo diferencias significativas entre las dietas experimentales. En el segundo bioensayo, los juveniles alimentados con la dieta experimental + aditivos alimentarios incrementaron significativamente supervivencia, FCR, FC y THC comparado con la dieta control. El crecimiento de juveniles se incrementó significativamente con las dietas CP29% y CP29%+mezcla de levaduras, comparado con el crecimiento de la dieta control. La dieta complementada con la mezcla de levaduras mostró el valor más alto de supervivencia y THC de juveniles comparado con los demás tratamientos experimentales. Los diferentes niveles experimentales de CP incluidos en la dieta de camarón incrementaron crecimiento, supervivencia y hemocitos circulantes; la adición de una mezcla de levaduras como aditivo alimentario, indujo mejor supervivencia y respuesta inmune en juveniles de camarón.

Shrimp diets with mixtures of probiotics (bacilli or yeasts) were evaluated on the production response and immunological effect on juvenile shrimp (Litopenaeus vannamei). The results showed a significant effect in growth, food consumption and feed conversion rate when probiotic diet was used. In addition, experimental diets with yeast mixture [C. insectorum (DH5), D. hansenii (DH6, and L1)] had a significantly higher amount of circulating haemocytes than those with bacilli [B. tequilensis (YC5-2), B. endophyticus (YC3-b) and B. endophyticus (C2-2)]. Shrimp fed both experimental diets (3x107 CFU mL-1) had a significantly higher growth and immune parameters when compared with the commercial diet. Both elements can contribute to the sustainable development and health of shrimp farming.

The presence of invasive species is an important element with high relevance associated to their impact on the environment. The aim of this work was to collect scientific information about a new invasive species (Penaeus monodon) reported on the Mexican coasts (2012), their possible origin, distribution mechanisms on the coasts of the American Atlantic, and their potential risk to the ecosystem. Historical scientific information about P. monodon in the American Atlantic showed that it was transported to Brazil and USA in 1987-1988 for aquaculture purposes, where escapes were reported. Penaeus monodon adults have been detect in coast of Brazil, Colombia, Costa Rica, Cuba, Guatemala, Mexico, USA and Venezuela from 1987 to 2016. Those results suggest the establishment of this specie in the American Atlantic Oceans. The evidence also indicates that P. monodon is an important competitor of space and food compared to local shrimp species, predator of other crustacean’s species and reservoir/transport of different pathogens like viruses, bacteria, and parasites. Additional studies and monitoring are required to assess and understand the population dynamics of this species in American Atlantic waters, their mechanisms of distribution, potential impact of this exotic species and their growth on the native biota, and their relevance as a natural reservoir of viral pathogens that affect the production of wild shrimp and culture., Resumen:La presencia de especies invasoras es un tema que está adquiriendo gran importancia debido al efecto en el medio ambiente que pueden generar. El objetivo del presente trabajo fue colectar información científica sobre una nueva especie invasora (Penaeus monodon) reportada en las costas mexicanas (2012), mostrando su posible origen, mecanismos de dispersión en las costas del Atlántico Americano y el riesgo potencial para el ecosistema. La información científica histórica sobre P. monodon en el Atlántico Americano señala que fue trasladado a Brasil y EUA en 1987-1988 con fines de cultivo, donde además se reportaron fugas de esta especie. Desde 1987 al 2016 se han detectado adultos silvestres de P. monodon en Brasil, Colombia, Costa Rica, Cuba, EUA, Guatemala, México, y Venezuela, lo que sugiere el establecimiento de esta especie en las aguas del Atlántico Americano. La evidencia también señala que P. monodon es un importante competidor de espacio y alimento de especies locales de camarón, posible depredador de otros crustáceos y reservorio / vehículo de diferentes agentes patógenos (virus, bacterias y parásitos). Es importante profundizar en las investigaciones sobre la dinámica poblacional que presenta esta especie en aguas del Atlántico Americano, sus mecanismos de distribución, consecuencias potenciales que puede generar su crecimiento poblacional sobre la biota nativa, además de su importancia como reservorio natural de agentes patógenos virales que afecten la producción de camarón silvestre y de cultivo.

Objetive . Evaluation of hematological and biochemical parameters of culture channel catfish (Ictalurus punctatus) under acute stress by management and capture practice. Materials and methods . Fish (200 g mean) were maintained in culture tanks and divided in two treatments, in duplicate, (n=15x2x2=60 fishes). Thirty catfish were exposed for 5 min to acute stress (TE) by management and capture practice, while other group not (control group, TnE). 10 fish for treatment were collected at 0, 6, and 24 h post-stress for blood collection, where TnE fishes were anesthetized along work. Complete blood count (manual method) and blood biochemical (spectrophotometry) of fish samples were evaluated and their results were analyzed using a Student's t-distribution. Results . The erythrocytes, hematocrit, hemoglobin and glucose level of TE animals was significantly higher (p<0.05) at 6 h post-stress, in comparison of TnE. Immune cells in fish TE decreased at 6 and 24 h post-stress, where leukocytes and lymphocytes were significantly lower that TnE (p<0.05) at 24 h post-stress. Other evaluated parameters did not show significant differences along this study. Conclusions . Those results suggest that several hematological and blood biochemical parameters in fish changed by acute stress generated by management and capture practice., RESUMEN Objetivo . Evaluar los efectos del estrés agudo debido al manejo y captura sobre los parámetros hematológicos y bioquímicos en bagre de canal (Ictalurus punctatus) bajo cultivo. Materiales y métodos . Los peces (200 g promedio) fueron mantenidos en tanques de cultivo y divididos en dos tratamientos, por duplicado, (n= 15 x 2 x 2 = 60 peces). Treinta bagres fueron expuestos por 5 min a estrés agudo (TE) por manejo y captura, mientras que otro grupo no (grupo control, TnE). Diez peces de cada tratamiento fueron colectados a las 0, 6, y 24 h post-estrés para la extracción de sangre, los bagres del TnE fueron anestesiados durante su manejo y captura. Se evaluó el hemograma (método manual) y bioquímica sanguínea (espectrofotometría). Los resultados fueron analizados mediante la prueba de t student. Resultados . El contenido de eritrocitos, hematocrito, hemoglobina y glucosa de los animales TE fue significativamente mayor (p<0.05) a las 6 h post-estrés en comparación de TnE. Las células inmune en peces TE disminuyeron a las 6 y 24 h post-estrés, siendo leucocitos y linfocitos significativamente menores en el TnE (p<0.05) a las 24 h post-estrés. Otros parámetros evaluados no presentaron diferencias significativas en lo largo del estudio. Conclusiones . Los resultados sugieren que varios indicadores hematológicos y bioquímica sanguínea en los peces son alterados por el estrés agudo ocasionado por manejo y captura.

The presence of diseases caused by virus and bacteria pose a threat to the capture and commercialization of shrimp, and may cause significant economic damage. Nocturnal monthly sampling were conducted to detect the presence of IHHNV, WSSV, and NHP in San Andres Lagoon in Tamaulipas, Mexico, an important coastal ecosystem due to its shrimp fishery and the existence of shrimp farms in the area. Polymerase chain reaction (PCR) analysis in the shrimp tissue did not detect the presence of IHHNV, however, WSSV was detected, as well as NHP during July and August, when low salinities and high temperatures were recorded.

In February 2012, a reproductive group of 60 adult blackbucks (Antilope cervicapra) from Veracruz, Mexico was relocated to hunting units in eastern and northeastern Mexico. Seven individuals died due to hemorrhagic parasitic, abomasitis and enteritis caused by Haemonchus spp., Setaria spp., and Trichostrongylids. Deaths were associated with hepatic necrosis, bilateral congestive distention of heart and fibrinonecrotic bronchopneumonia. Also Anaplasma marginale was identified. The blackbucks' population displayed a general mortality rate of 11.67%, where 25% of total male and 9.62% of total female died. The mortality was controlled by segregation of all remaining blackbucks and the treatment for internal and external parasites (biting flies and ticks). After the treatment, no fatality cases related to parasitosis were recorded. The results presented here exhibit the high relevance of parasitosis as possible factor risk in the survival of tis specie., En febrero del 2012, un grupo de 60 individuos adultos reproductivos de antílope negro (Antilope cervicapra) provenientes de Veracruz, México fueron reubicado en unidades de cacería del este y noreste de este país. Siete individuos murieron presentando hemorragias parasíticas, abomasitis y enteritis ocasionadas por Haemonchus spp., Setaria spp. y Trichostrongylids. Las muertes estuvieron asociadas con necrosis hepática, distensión congestiva del corazón y bronconeumonía fibronecrótica, donde Anaplasma marginale fue identificada. La población de antílopes negros mostró un porcentaje de mortalidad del 11.67%, en donde el 25 y 9.62% de los machos y hembras totales murieron. La mortalidad fue controlada mediante el aislamiento de los antílopes negros restantes y un tratamiento contra parásitos internos y externos (garrapatas y moscas picadoras), lo cual controló las mortalidades y reveló la importancia de la parasitosis como factor de riesgo que afecta la sobrevivencia de esta especie.

The probiotics are products based on different microorganism strains, those products have evolved from a just simple mixture of active bacteria to products with specific properties of adherence, colonization, synergies, antibacterial activity, etc. Probiotic products for livestock and aquaculture production are designed with strains developed to operate under specific conditions and which need to be understood and taken into account by the producers because different results can be observed depending of specie(s), geographic area, and type of culture production. The available information suggests that probiotic display a progress from: (a) a better understanding of the bacterial micro-ecosystem and target organs, (b) strain source and their particular characteristics, (c) doses and target species, (d) specific adhesion and/or colonization mechanisms, (e) specific activation of the immune system, and, (f) environmental effects. The aim of this manuscript is to provide information to the livestock and aquaculture producers about the characteristics and qualities of probiotic so they can carry out a proper selection and use., Los probióticos han evolucionado pasando de ser solo sencillas mezclas de bacterias activas a ser productos con propiedades delimitadas de adhesión, colonización, sinergismos, producción de productos antibacterianos, etc. Los productos probióticos para la producción pecuaria y acuícola son diseñados con cepas desarrolladas para funcionar bajo condiciones específicas, las cuales deben ser tomadas en cuenta por los productores ya que los resultados se ven modificados dependiendo de la especie en donde se use, área geográfica de aplicación y tipo de cultivo. La información disponible sugiere que el progreso de los probióticos se ha dirigido hacia: (a) un mejor entendimiento del micoecosistema bacteriano y órganos blanco de las bacterias, (b) fuente de la cepa y sus características particulares, (c) dosis de aplicación y especies donde se puede aplicar, (d) mecanismos específicos de adhesión o colonización, (e) forma de activación del sistema inmune y (f) como afecta el medio ambiente a la preparación probiótica. La presente revisión está destinada a brindarle al productor pecuario y acuícola la información sobre las cualidades y características de los probióticos, a fin de que este pueda llevar a cabo una adecuada selección y uso de los mismos.

The probiotics are products based on different microorganism strains, those products have evolved from a just simple mixture of active bacteria to products with specific properties of adherence, colonization, synergies, antibacterial activity, etc. Probiotic products for livestock and aquaculture production are designed with strains developed to operate under specific conditions and which need to be understood and taken into account by the producers because different results can be observed depending of specie(s), geographic area, and type of culture production. The available information suggests that probiotic display a progress from: (a) a better understanding of the bacterial micro-ecosystem and target organs, (b) strain source and their particular characteristics, (c) doses and target species, (d) specific adhesion and/or colonization mechanisms, (e) specific activation of the immune system, and, (f) environmental effects. The aim of this manuscript is to provide information to the livestock and aquaculture producers about the characteristics and qualities of probiotic so they can carry out a proper selection and use. DOI: 10.17268/sci.agropecu.2013.02.06

The culture of aquatic organisms show a high relevance in the human feeding and the culture activities can create artificial conditions that increase the growth and selection of specific bacteria. Vibrio species are normal bacteria’s from microflora of penaeid shrimp, those are opportunistic pathogens that can take advantage of the ecological changes generated for the culture of aquatic organisms and which may cause diseases, low survival and economic losses in the shrimp production. The aim of this research was to determine the variation in the survival of different larval substages (nauplius, zoea I-III, mysis I-III) and postlarvae 1, of Pacific white shrimp Litopenaeus vannamei exposed at three doses [103 , 105 , and 107 colony-forming unit (CFU) ml-1 [ of V. harveyi, by immersion (30 min) as infection method. This species generated a significant low survival in larvae (p < 0.05) only in high doses (105 and 107 CFU ml-1 ), where higher doses show the lowest values of survival. Larval substages and postlarvae 1 of shrimp showed sensitivity associate to the increase of Vibrio doses and this sensitivity decreased with the growth of larval substages and postlarvae 1. This information has high significance for the fisheries and aquaculture industry, which help to generate strategies to reduce the effects of V. harveyi with positive effect in growth and survival of the shrimp larvae and postlarvae 1. DOI: 10.17268/sci.agropecu.2013.02.05