Pacific white leg shrimp were stocked (150 PL m-3) into one of four plastic-lined 1000 m3 (0.1 ha) ponds. Ponds were randomly fed one of two diets in duplicate: a commercial shrimp feed (Grobest® Vista Eco), or an open formula, experimental, fishmeal and fish oil-free diet (F3). Shrimp were fed by hand and automatic feeders using commercial feed tables for 56 days. Sub-samples of shrimp (n = 50) were weighed weekly from each pond to evaluate growth and adjust feeding rates. Following harvest, no differences were observed between diets for survival. Combined pond biomass was 2045.0±45.96 kg (S.D.) and 2302.5±28.99 kg for commercial and F3 shrimp respectively. FCR were 1.15±0.00 and 1.03±0.01 (P< 0.05). Individual F3 fed shrimp were significantly (P< 0.05) heavier at trial termination with animals fed the commercial diet weighing 18.03±0.24 g versus 23.25±0.84 g (P< 0.05). Total hemocyte counts were 33.26±0.46 and 33.88±0.72, that for semi-granular cells 20.19±1.65 and 18.72±0.81, granular cells, 15.20±1.39 and 15.56±0.15, hyaline cells, 64.62± 3.01 and 65.72±0.96, and phenoloxidase activity, 56.87±6.12 and 50.29±0.55, for commercial and F3 fed shrimp respectively. A basic economic analysis indicated increased profitability for the F3 fed shrimp (US$7362.43 versus US$10665.62) with a return on investment (ROI) of 64.5% for the commercial feed and 89.8% for the F3 ponds. There were no differences between samples for proximate composition, cooked tail color as assessed by a BASF Salmon Color Fan or texture, as determined by a texture analyzer. Results from this trial unconditionally demonstrate the practicality of cultivating white leg shrimp using marine resource-free-based diets without impacting growth performance or consumer acceptability, while returning increasing ROI.

Corresponding to projected global population growth, the world's food production systems must likewise enlarge substantially if current levels of dietary protein intake are to be maintained. The anticipated growth curve for global aquaculture, and especially for shrimp farming, which is forecast to double production by 2030, will inevitably result in shortfalls in currently favored dietary ingredients: fishmeal (FM) and fish oil (FO). Servicing the projected FM-FO shortfall with marine products would be a formidable task as economic, social, moral, safety and environmental issues have forced the feed sector to examine the use of alternative, non-marine, ingredients. Herein, various alternative protein and lipid sources were evaluated as substitutes for FM-FO in Pacific whiteleg shrimp diets. Growth trials were coupled to challenges with viral and bacterial pathogens to assess potential benefit or disadvantage of ingredient switching. No differences (P > .05) were observed between control and test diets regarding growth or survival, Average Daily Gain (g d−1) or Specific Growth Rate (% d−1) over a 56-day period. Moreover, response to post-feeding trial challenge with EMS/AHPND or WSSV also did not differ between diets (P > .05). However, there was a difference in size/age responsiveness to bacterial challenge, with younger animals succumbing to infection more rapidly (P ≤ .035). Similar responses were observed for shrimp exposed to WSSV over the first 5-days post-challenge (P ≤ .02) after which survival rates equalized. Overall, the results support the sustained belief that FM-FO constituents of Pacific whiteleg shrimp diets can be totally replaced by non-marine ingredients that are nutritionally equivalent. Improvement in responsiveness to substitute proteins and oils might be further gained with more judicious blending of ingredients and use of other additives. Such manipulations could also result in less expensive sustainable feeds.

Diets were manufactured for largemouth bass (LMB) replacing fishmeal (FM) with poultry by-product meal (PBM), soybean meal (SBM), and a hydrolyzed soy meal. Experimental diets included a FM control (FMC), and three FM-free formulations containing equal amounts of PBM and SBM with fish oil (diet F2), Algal meal DHA (F3) or a soy protein concentrate (SPC). A commercial LMB diet was included for reference. Fish (n=20 per group) were randomly dispersed into one of 20 tanks with group weights of ±5%, and densities of 7.39±0.17 kg m-3. Tanks were maintained as a RAS (28.3±0.76 oC, DO2 at 7.7±1.19 mg L-1) and randomly assigned to one of the five diets (n=80 fish per diet). Animals were fed to apparent satiation 3x daily for 12-weeks. Groups were weighed every 3 weeks and feed consumption recorded for calculation of FCRs. At trial end all fish were weighed and measured individually and 3 fish per tank employed for various analyses and comparisons against pre-trial samples. At trial end no differences (P > 0.05) were observed between groups for growth, SGR, or condition. FCR differed between the commercial and F3 diets (P < 0.05). F2 fed fish had higher (P < 0.05) visceral fat than F3 fed fish. Survival was 98-100% across all groups. Results indicate that judicious dietary manipulations may allow elimination of FM from LMB diets without compromising overall performance.

Largemouth bass (LMB) were fed diets developed to substitute fishmeal (FM) using a blend of alternative proteins. Diets included a FM control (FMC), two FM-free formulæ (FMF), one of which (FFF) was formulated using an algal oil replacing fish oil (FO) and, for comparative purposes, a commercial LMB feed (COM). Fish (densities of 3.11±0.29 kg m-1) were arbitrarily distributed into one of eight tanks configured as a recirculating system (RAS; 28.3±0.76 oC; DO2: 7.7±1.19 mg L-1) and tanks randomly assigned to one of the four treatments (i.e. each treatment was tested in duplicate). Animals were fed 3x daily to apparent satiation and group weighed every 3 weeks for 18 weeks. No differences were observed in feed consumption between groups (P >0.05) but LMB fed the COM diet were heavier (P< 0.05) than fish fed the FMF and FFF feeds. In efforts to verify whether fish fed the FM/FO-free were authentic, samples were assessed by stable isotope ratio mass spectrometry. δ15N fish muscle isotope values at trial end were indicative of dietary FM substitution. A preliminary blind taste trial undertaken using fish from the FFF and COM diets did not differentiate between treatments (P > 0.05). Results from the present study show that, with prudent dietary control, complete replacement of FM/FO in LMB diets is attainable and verifiable, without compromising growth performance or consumer acceptance of the final product.