Production yields of the marine shrimp, Litopenaeus vannamei, cultured in earthen ponds in the Gulf of Nicoya, Costa Rica were studied to evaluate the effect of diseases diagnosed during El Niño 2015 event. Two culture systems on earthen ponds were used: three short cycles (SC) per year in farms with low disease incidence and two long cycles (LC) per year in highly affected farms with high mortality. Survival was low in the 2 CL (35.3 ± 3.2%) as compared to the 3 CC (63.1 ± 3.2%). An inverse relationship between average weight at harvesting and the final culture density was obtained (20.3 ± 0.8 g in 2 CL and 15.2 ± 1.6 g in 3 CC) as well as a growth compensation (1.29 ± 0.12 and 1.08 ± 0.10 g/week in 2 CL and 3 CC, respectively). The final production was directly proportional to the survival, with an average of 717 ± 8 kg/ha in 2 CL and 941 ± 53 kg/ha in 3 CC. The production was...

Production yields of the marine shrimp, Litopenaeus vannamei, cultured in earthen ponds in the Gulf of Nicoya, Costa Rica were studied to evaluate the effect of diseases diagnosed during El Niño 2015 event. Two culture systems on earthen ponds were used: three short cycles (SC) per year in farms with low disease incidence and two long cycles (LC) per year in highly affected farms with high mortality. Survival was low in the 2 CL (35.3 ± 3.2%) as compared to the 3 CC (63.1 ± 3.2%). An inverse relationship between average weight at harvesting and the final culture density was obtained (20.3 ± 0.8 g in 2 CL and 15.2 ± 1.6 g in 3 CC) as well as a growth compensation (1.29 ± 0.12 and 1.08 ± 0.10 g/week in 2 CL and 3 CC, respectively). The final production was directly proportional to the survival, with an average of 717 ± 8 kg/ha in 2 CL and 941 ± 53 kg/ha in 3 CC. The production was...

This paper presents the findings obtained from a series of analyzes carried out for a freshwater prawn maturation of Macrobrachium rosenbergii in Costa Rica. A large larval production centre had recurrent abortions of gravid females, as well as high mortality in larval and post-larval stages. The results indicate that increases in the presence of organic matter in the water of the tanks caused high prevalence of ectoparasites in the ovigerous masses, as well as high bacterial counts in the water column. This condition generated bacterial and parasitic infections in larvae with severe reduction in production.

The incidence of bacterial infections in shrimp hepatopancreas cultivated in the Gulf of Nicoya, Costa Rica, presented a high impact on yields in 2016-2017, affecting the survival of the animals and shrimp farm production. In addition, important incidences of Baculovirus penaei, detected in post-larvae used in part of the shrimp ponds, were reported. An Odds Ratio analysis was performed in an observational case-control study to determine the possible participation of this virus as a risk factor for subsequent bacterioses. The study demonstrates the active participation of Baculovirus penaei as an important risk factor. Survival data are presented by ponds infected by the virus vs free ponds.

Se presentan los hallazgos obtenidos de una serie de análisis realizados para un laboratorio de maduración de langostinos de agua dulce de Macrobrachium rosenbergii en Costa Rica. En este centro de producción larval se presentaron abortos recurrentes de hembras grávidas, así como gran mortalidad en los estadios de larvas y pos-larvas. Los resultados indican que incrementos en la presencia de materia orgánica en el agua de los tanques causaron altas prevalencias de ectoparásitos en las masas ovígeras, así como elevados conteos bacteriales en la columna de agua. Esta condición generó cuadros de bacteriosis y parasitosis en las larvas con severas reducciones en la producción.

The incidence of bacterial infections in shrimp hepatopancreas cultivated in the Gulf of Nicoya, Costa Rica, presented a high impact on yields in 2016-2017, affecting the survival of the animals and shrimp farm production. In addition, important incidences of Baculovirus penaei, detected in post-larvae used in part of the shrimp ponds, were reported. An Odds Ratio analysis was performed in an observational case-control study to determine the possible participation of this virus as a risk factor for subsequent bacterioses. The study demonstrates the active participation of Baculovirus penaei as an important risk factor. Survival data are presented by ponds infected by the virus vs free ponds.