Tag Carlos A. Ching

Automatic feeding is becoming important for lowering production costs through better shrimp growth, lower feed conversion rate and higher survival rate. 

In a survey of Vibrio concentrations in white shrimp postlarvae at two inland farms, hatchery postlarvae were acclimated in water with salinity reduced from 30 and 5 ppt to 2 ppt at the farms. One farm stocked postlarvae in nursery ponds, and the other stocked directly into grow-out ponds. 

Applied to shrimp postlarvae at Thai and Latin American farms, a thermal treatment of constant water temperature increased final survival rates. 

Monitoring of Vibrio bacteria in shrimp larvae determined a relationship among hepatopancreas color, bacteria concentration and signs of early mortality syndrome. 

Establishing postlarvae quality has become one of the most important aspects in controlling diseases in farmed shrimp. Initial microbial testing can ensure viruses and other pathogens are absent from the animals. 

Based on the results of a study in Peru, the authors found that the high volumes of quick lime and hydrated lime needed to effectively control vibriosis outbreaks in shrimp ponds would raise pH levels in culture water and stress the animals under culture. 

Controlled by timers, automatic feeders should be placed in deeper areas of ponds and away from aerators. Overfeeding is rare during automatic feeding, and pond bottom quality is maintained through grow-out cycles. 

At higher stocking densities, the application of all feed via feed trays often results in feed being dropped outside and/or underneath the trays. 

In laboratory tests with white shrimp, feed consumption was 36.5 percent higher at 33 degrees-C than at 29. Growth was similar at both temperatures. 

The authors evaluated the feed passage through the intestines of white shrimp under laboratory conditions. Feed consumption on feed trays was tested four times daily at different temperatures at an intensive culture farm. 

A technique based on checking the color of the shrimp intestine can complement the use of feed tables and trays, which are less effective at high temperatures, when no leftovers are found. 

The authors have established a procedure to reduce the impacts of Taura Syndrome Virus in the culture of Pacific white shrimp. The procedure focuses on avoiding the molting process of shrimp by limiting culture conditions.