Effect of dietary potassium diformate (KDF) on growth performance of juvenile Asian seabass (Lates calcarifer) reared under freshwater conditions

Transcription

1 Effect of dietary potassium diformate (KDF) on growth performance of juvenile Asian seabass (Lates calcarifer) reared under freshwater conditions J. Arreza, O. Jintasataporn, N. Areechon, K.-J. Kühlmann and C. Lückstädt* Kasetsart University, Bangkok, Thailand ADDCCON Asia Co Ltd., Samut Prakarn, Thailand *ADDCON, Germany Abstract #325 FAO, 2014

2 Asian seabass in aquaculture only started in the mid-80ies of last century main producing countries are Taiwan, Malaysia, Thailand, Indonesia and Australia latest figures from 2012 show an Asian seabass production of >75,000 t (FAO) Source: FAO, 2014 FAO, 2014

3 Acidifiers in aquaculture feeds Organic acidifiers Organic acids and their respective salts applied as feed additive Advantages Fish & shrimp unfavourable conditions for pathogenic bacteria supports protein- and mineral digestion increases growth performance Feeds protects raw materials and processed feeds from bacterial degradation Organic acidifiers the alternative functional feed additives in modern aquaculture

4 Acidification Organic acids inhibit bacterial growth thereby preventing degradation of feed; healthy intestine + improved digestibility

5 Use of dietary acidifier in aquaculture Organic acids: formic acid, acetic acid, propionic acid, lactic acid and citric acid Organic acid salts: calcium formate, sodium formate, potassium diformate (KDF), sodium diformate, calcium propionate, calcium lactate, sodium butyrate Inorganic acids: phosphoric acid Review papers: Lückstädt, 2008; Ng and Koh, 2011

6 Chemical structure of KDF Formic acid Potassium diformate (KDF)* Formic acid (35%) Formate (35%) Potassium (30%) *KDF: crystalline, granular compound

7 Published data on diformates in aqua-diets Tropical: Ramli et al., 2005 tilapia grow-out in Indonesia Zhou et al., 2008; Ng et al., 2009; Cuvin-Aralar et al., 2012 juvenile tilapia Lückstädt and Schroeder, 2010 milkfish grow-out in marine cages Jintasataporn et al., 2011 white shrimp grow-out in Thailand Lückstädt, 2012 meta-analysis on tilapia Abu Elala and Ragaa, 2014 tilapia grow-out in Egypt Temperate: Lückstädt and Schulz, 2008 digestibility in salmon in sea water Lückstädt, 2010 grow-out of rainbow trout in raceways Morken et al., 2010 fish feed based on barley protein concentrate Morken et al., 2011 digestibility in rainbow trout

8 Seabass trial, Thailand M&M I Kasetsart laboratory; tanks in static-renewal system 240 litre tanks 6 tanks per group culture period: 75 days feeding a diet containing ~54% CP stocking (BM = 16.5 g) feeding with 0.5% KDF harvest (BM > 55 g) vs. negative control group

9 Seabass trial, Thailand M&M II main ingredients of Australian-formulated diets: fish meal wheat blood meal squid meal defatted soybean fish oil resulting proximate composition Parameter Percentage Crude protein 54.6 Crude lipid 5.3 Crude fibre 0.6 Ash 13.6 Energy (calculated) 4715 kcal/kg

10 Seabass trial, Thailand M&M III groups: 0.5% potassium diformate vs. negative control (60 fish per group with 6 replicates) feeding: 2% body mass equivalent (BME) feeding was adjusted weekly from the 3rd week onwards feeding time: 3 times daily FAO, 2014 FAO, 2014 stocking (BM = 16.5 g) feeding with 0.5% KDF harvest (BM > 55 g) vs. negative control group

11 Weight in g Effects of KDF on seabass performance I 0.5% dietary KDF in seabass weight development till day FAO, NC 0.5%KDF Days

12 Effects of KDF on seabass performance II 0.5% dietary KDF in Asian seabass - fed for 75 days Parameter Negative control 0.5% KDF P-value Final weight [g] 54.5± ± Weight gain [g] 38.8± ± Survival [%] 82.0± ± FCR 2.72± ± FPI* 141±80 243± *FPI = Fish Productivity Index = Weight gain [g] Survival [%] / (10 x FCR)

13 Effects of KDF on seabass performance III 0.5% dietary KDF in Asian seabass - fed for 75 days impact on Protein Efficiency Ratio Parameter Negative control 0.5% KDF P-value PER* 0.75± ± *PER=Protein Efficiency Ratio: Weight gain [g] / Protein intake [g]

14 Discussion of results Growth performance weight gain of Asian seabass fed with KDF inclusion was almost 20% higher compared to control FCR of fish fed with the dietary acidifier tended to be improved by more than 28 %... not significant though due to high SD crucial impact on survival improved significantly by almost 20% seabass fed with 0.5% potassium diformate improved overall fish productivity by 72%, including the important impact on protein efficiency limited impact of dietary acidifier due to too clean laboratory conditions effects under pond conditions often more pronounced results are largely in agreement with previously reported studies on the effect of potassium diformate (KDF) in tilapia (meta-analysis available) and Pangasius

15 The use of KDF in fish nutrition - aiming towards sustainable aquaculture! Thank you! increasing growth saving feed costs FAO, 2014 strong antimicrobial effects high survival rates