TECHNICAL REPORT - GROWTH TRIAL. Objective and Background

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1 TECHNICAL REPORT - GROWTH TRIAL Objective and Background A growth trial was carried out to evaluate the efcaca of protected feed attractant mixtures (PFAM) in Pacifc white shrimp Litopenaeus vannamei fed high soa diets under grow-out conditions. The growth trial was conducted at Integrated Aquaculture International s shrimp nutrition center in Kauai. Prior to the growth trial, a series of attractabilita and palatabilita assaas were conducted in the laboratora at Georgia State Universita to evaluate the efcaca of protected feed attractant mixture (PFAM) in comparison with krill meal that is commonla used as a feed attractant in shrimp feeds. Protected feed attractant feed mixtures at inclusion levels of 1 and 5% of the diet were found to perform as well or better than krill meal included at 5% of the diet. Growth Trial Juvenile L. vannamei produced from SPF broodstock at Integrated Aquaculture International s (IAI) breeding program were used during the studa. Juveniles weighing approximatela 2 g were stocked in to 750-L fber glass microcosm tanks equipped with automatic feeders and self-cleaning bottoms. The experimental sastem was supplied with water from a shrimp pond and the trial was run under green water conditions. Four fshmeal-free experimental diets were formulated and prepared for the growth trial. The diets were formulated to contain approximatela 42% crude protein and 8% crude fat and supplied the known nutrient requirements for the species (Table 1). The diets contained soabean meal, soa protein concentrate, wheat four, corn protein concentrate, wheat gluten, fsh oil, phospholipids and cholesterol. The experimental diets were a negative control (NC) that did not contain ana feed attractant, a diet that contained 5% krill meal as attractant (KRL), and diets that contained 1% of a protected feed attractant mixture and 5% of a protected feed attractant mixture (1PFAM and 5PFAM respectivela). Sinking diets (2mm) were made at IAI s nutrition center in Kauai and were analazed for their nutritional composition (Table 1). Following acclimation to the microcosm tanks for one week prior to the initial weighout groups of shrimp were weighed to ensure that tank weights were within 5% of one another and not signifcantla diierent. Following the initial weigh-out tanks were randomla assigned a dietara treatment (N=5) and fed their respective diet for a period of 8 weeks. Each tank contained 30 shrimp with a mean initial weight of approximatela 2.3g. Shrimp were fed the experimental diets ba means of automatic belt feeders and daila rations were determined using feeding tables available in the literature (Tacon et al. 2013). A random sample of animals from each tank was weighed each week to obtain estimates of tank weights and to make adjustments to feeding rates. Water temperature and dissolved oxagen concentrations were monitored twice daila for each tank and other water qualita parameters such as

2 ammonia, nitrite and ph were measured weekla and maintained at optimal levels for this species. At the end of the 8wk trial shrimp were weighed and along with data on feed oiered were used to estimate growth and feed utilization in the diierent dietara treatments. The experiment was designed and analazed as a one waa ANOVA with each tank as an experimental unit. Means found to be signifcantla diierent (p<0.05) were compared using Fisher s LSD test. Results The results of the growth trial are shown in Table 2. The initial weights of the diierent treatment groups were not signifcantla diierent from one another. Survival was not signifcantla aiected ba dietara treatment. The mean fnal weights of treatment groups KRL and 1PFAM were signifcantla higher than those of the 5PFAM and the negative control NC groups. The fnal weight of KRL and 1PFAM were not signifcantla diierent from one another. There were also no diierences in fnal weight between 5PFAM and NC. Similarla mean weight gain per shrimp and growth rate per week were signifcantla higher in treatment groups KRL and 1PFAM compared to those in 5PFAM and NC. There were no signifcant diierences in weight gain and growth rate between KRL and 1PFAM and also between 5PFAM and NC. The feed conversion ratio (FCR) in KRL was signifcantla better than those in NC and 5PFAM but not in 1PFAM. The FCR in KRL and 1PFAM were not signifcantla diierent from one another. Conclusion The growth trial showed that a high soa diet containing 1% protected feed attractant mixture was as attractive and palatable as a high soa diet containing 5% krill meal. The 1% PFAM diet also promoted signifcantla higher growth than the 5% PFAM and negative control diets. These results are similar to those observed in the laboratora based attractabilita and palatabilita assaas. These results also demonstrated that protecting the feed attractant mixtures promoted prolonged feeding thereba resulting in higher growth and reduced feed waste. Based on the results it should be possible to further optimize the protected feed attractant mixtures to obtain high growth rates at lower inclusion rates and cost. References Tacon, A. G. J., Jora, D., Nunes, A Shrimp feed management: issues and perspectives. In M. R. Hassan and M. B. New, eds. On-Farm Feeding and Feed Management in Aquaculture. FAO Fisheries and Aquaculture Technical Paper No Rome, FAO. Pp

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4 Table 1. Composition of experimental diets 1 fed to Pacific white shrimp Litopenaeus vannamei Ingredients, % of diet NC KRL 1PFAM 5PFAM Soybean Meal Soy Protein Concentrate Wheat Flour Corn Protein Concentrate DL-Methionine L-Lysine HCl Monocalcium Phosphate Menhaden Oil Lecithin Cholesterol Wheat Gluten Sodium Alginate Vitamin/Mineral Premix* Sodium Bentonite Krill Meal 0 5 1% FAM Protected Premix % FAM Protected Premix Proximate and Nutrient Composition, % of diet Dry Matter Crude Protein Crude Fat Ash Crude Fiber Cholesterol Arginine Cystine Histidine Isoleucine Leucine Lysine Methionine Methionine + Cystine Phenylalanine Threonine Tyrosine Valine * Vitamin/Mineral Premix contained the following per kg of premix: Vitamin A 3,500,000 IU, Vitamin D3 1,500,000 IU, Vitamin E 75g, Vitamin K3 15g, Vitamin B1 12.5g, Vitamin B2 10 g, Vitamin B6 12.5g, Vitamin B g, Niacin 50g, Pantothenic Acid 40g, Biotin 0.5g, Folic Acid 5 g, Vitamin C 100 g, Copper 12.5g, Iron 15 g, Manganese 15g, Iodine 0.5 g, Cobalt 0.1 g, Zinc 50 g, Selenium g. NC = negative control diet that did not contain any attractant, KRL =krill meal diet, 1PFAM and 5PFAM contained 1% and 5% of a protected feed attractant respectively.

5 Table 2. Performance of Pacific white shrimp Litopenaeus vannamei fed fishmeal-free diets that contained no feed attractant (NC, negative control), krill meal (KRL, krill meal) or protected feed attractant mixture at 1 or 5% of the diet (1PFAM, 1% protected feed attractant mixture or 5PFAM, 5% feed attractant mixture respectively) for 8 weeks. Significant responses for a response parameter (within a row) are denoted by alphabet superscripts (P<0.05). Results are mean values per shrimp standard deviation (N=5). Response NC KRL 1PFAM 5PFAM Initial Weight, g/shrimp Final Weight, g/shrimp b a a b Weight Gain, g/shrimp b a a b Growth Rate, g/wk/shrimp b a a b Survival, % Total Feed Intake, g/shrimp Feed Conversion Ratio, feed/gain ac b ab c