Background:

There are no studies on nutrient leaching from feces in shrimp (Litopenaeus vannamei).

Goals:

Estimate the nutrient loss in feces from the Pacific white shrimp.

Methods:

A bioassay was conducted in order to evaluate the effect of collection time on nutrient loss in feces. Dry matter (DM), crude protein (CP), amino acids (AA), and concentration of chromic oxide (Cr2O3) were measured in feces. Fifteen juveniles of Pacific white shrimp having an average weight of 4.9 ± 0.1 g were distributed in 4 replicate aquariums per treatment. Shrimp were fed with a reference diet (commercial diet) that was previously reprocessed to add 1% chromic oxide as an inert marker and 1% sodium alginate (binder). Treatment 1(T1) consisted of leaving the feces in seawater for 3 hours after collection. In addition, there was alternation between the treatments in the replicates. In the second treatment, feces were immediately collected and frozen after they were emit ted (T2).

Results:

The content of DM, CP, and total amino acids in feces for both treatments was similar. The same result was observed for the apparent digestibility coefficients of DM, CP, and total amino acids.

Conclusions:

Based on these results, we can infer that under the conditions of this experiment, nutrient leaching from juvenile Litopenaeus vannamei feces is not affected by collection time in a period equal or less than 3 hours after emission and, therefore, there is no effect on the estimation of the apparent digestibility coefficients of DM, CP, and amino acids.