SOLUABLE ACIDIFIERS IN A SHRIMP (L.vannamei) TRIAL

Ekachai Jenwitheesuk1, Fridtjof Galster1, Andreas Lewke1,Tilman Wilke1
1 Dr. Eckel GmbH
Im Stiefelfeld 10
56651 Niederzissen, Germany
e.jenwitheesuk@dr-eckel.de

 

Acidifiers are an indispensable part of most livestock diets. Increasingly they are present in aquaculture feeds as well, to promote growth and protein digestibility, and decrease mortality while improving feed hygiene. Shrimp pose a challenge for additives as they feed more reluctantly than tilapia or salmonids, so acidifiers have to have a slow, controlled solubility to avoid leaching from the feed pellets. The present trial investigated whether a high inclusion rate (5kg/t) of a novel acidifier (Ca+ Aq) affects palatability of shrimp feed, and how the addition of the acidifier could improve growth of pacific white shrimp (L.vannamei).

Trial setup was initially shrimp were stocked as PL 12 for two month pre-growth and adaptation period and to allow for easier handling and more accurate measurements. For the 57 day trial 74 shrimp were selected in three body weight groups to ensure equal stocking densities (kg/m2) at the trial onset. Shrimp were equally distributed over control and trial group, salinity (25ppt), aeration (4-7mg/l), temperature (30°C) and other key factors were identical for both groups. Animals were measured twice at day 0 and day 57 in order to minimize stress for the animals.

As a first trail with a novel species in the tank setup the study was successful. Overall the animals grew and fed well (Table 1), showed no clinical signs of disease and mortality in the trail period was low (9%). The acidifier did not affect feed intake, but did lead to a marked increase in gain and improved FCR.