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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.

The inclusion of Yucca schidigera and Quillaja saponaria extracts (NTF) in aquatic organisms display a positive response on production and organism's physiology. Fifteen tanks (140 L) with low-salinity water (S = 5) were stocked with 10 juvenile shrimp (Litopenaeus vannamei, 2.6 g of mean weight) feeding with 0, 0.25, 0.5, 1.0 and 2.0 g kg-1 of NTF of basal diet (triplicate treatment). The shrimp were cultured in a close recirculation system (control condition) and fed ad libitum daily for 40 days. General growth parameters (body weight, growth, body length, feed conversion rate, survival) and hepatopancreatic digestive enzyme activities (alkaline protease, alkaline phosphatase, a-amylase, leucine aminopeptidase, and lipase) were evaluated after 40 days of shrimp culture. The final mean body weight, individual mean body, weight gain, and feed conversion ratio from shrimp feeding with 1.0 and 2.0 g kg-1 of NTF have a significant (P < 0.05) result compared to other treatments. The highest values of alkaline protease, lipase, and a-amylase were detected in shrimp feeding with 0.5 g kg-1 of NTF, where a high level of leucine aminopeptidase and alkaline phosphatase were detected with 0.25 g kg-1 of NTF treatment. However, any significant differences in enzyme activities were detected between the control group and treatments. The increase effect in shrimp growth and any decrease effect in enzyme activity detected in present study suggest that NTF shows potential as a feed additive for shrimp cultured at low-salinity. RESUMEN. El uso de extractos de Yucca schidigera y Quillaja saponaria (NTF) en organismos acuáticos ha mostrado una respuesta positivas en la producción y fisiología de los mismos. Quince estanques (140 L) con agua a baja salinidad (S = 5) fueron preparados con 10 camarones juveniles (Litopenaeus vannamei, 2,6 g de peso promedio), alimentados con 0; 0,25; 0,5; 1,0 y 2,0 g de NTF kg-1 en la dieta base (tratamientos por triplicado). Los camarones fueron cultivados en un sistema cerrado de recirculación (condiciones controladas) y alimentados ad libitum diariamente por 40 días. En los organismos se evaluaron los parámetros generales de crecimiento (peso y longitud del cuerpo, crecimiento, conversión alimenticia, supervivencia, etc.) y la actividad de enzimas digestivas hepatopancreáticas (proteasa y fosfatasa alcalina, a-amilasa, leucina aminopeptidasa y lipasas). El peso promedio final e individual, ganancia de peso, y conversión alimenticia fue superior en los camarones alimentados con 1,0 y 2,0 g kg-1 de NTF con valores significativamente positivos (P < 0,05), comparado con los otros tratamientos. El valor más alto de proteasa alcalina, lipasa y a-amilasa fue detectada en camarones alimentados con 0,5 g kg-1 de NTF. Un valor alto de leucina aminopeptidasa y fosfatasa alcalina se detectó en el tratamiento con 0,25 g kg-1 de NTF. Sin embargo, no se observó diferencia significativa entre tratamientos. El efecto positivo en el crecimiento y carencia de efectos negativos en la actividad enzimática mostrada en el presente trabajo sugieren que el NTF puede ser empleado potencialmente como aditivo alimenticio en camarones cultivados a baja salinidad.

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.

Diseases are of particular importance for aquaculture worldwide, particularly in intensive culture. In Mexico, intensive culture of channel catfish is mainly done in floating cages. The aim of the present study was to determine the presence of the myxozoan Henneguya and the effect of site, period and host length on its prevalence in cage-cultured channel catfish. Over a year, fish were examined on six different sites. Results showed the presence of Henneguya exilis in all the farms. However, no significant effects were observed for site and season on prevalence, nor was there a correlation between host length and infection prevalence. Las enfermedades tienen una gran importancia en la acuacultura mundial, especialmente en sistemas de cultivo intensivos. En México, el cultivo intensivo del bagre de canal se realiza principalmente en jaulas flotantes. El objetivo de la presente investigación fue el determinar la presencia del myxozoo Henneguya y el efecto del lugar, periodo y longitud del huésped con la prevalencia en el bagre de canal en jaulas de cultivo. Durante un año, se examinaron peces obtenidos de granjas en seis localidades. Los resultados mostraron la presencia de Henneguya exilis en todas las granjas, sin embargo no se observaron efectos significativos para el sitio y época en la prevalencia, ni hubo una correlación entre la prevalencia de la infección y la longitud del huésped.

Immune response of Lion’s paw scallop Nodipecten subnodosus to the challenge of Vibrio alginolyticus strain APSA2 was studied through the characterization of the activity of lysosomal enzymes and hemocyte size and number. Samples were obtained as hemocyte lysate supernatant (HLS) and plasma, after 6 and 24 hours, and 3, 6, and 10 days after challenge. The enzymatic activity was tested by colorimetric and lysoplate assay techniques. Between sampling times, significant differences in enzymatic activity determined by the colorimetric technique were found. The enzymatic activity was significantly higher in HLS than in plasma; in addition more enzymes were detected in HLS as compared with plasma. The enzymes with higher activity were leucyl arylamidase and esterase in both, HLS and plasma. Lysozyme-like activity did not show significant differences between the sampling times. However, in plasma the lysozyme-like activity was significantly higher than in HLS, suggesting that lysozyme was released from hemocytes into plasma as a first response to the challenge. A significantly negative correlation was found between protein concentration in plasma and in HLS. Based on the findings reported here, we can affirm that hemocytes and lysosomal enzymes are two of the mechanisms that this species has to fight bacterial attacks.