FEATURE
Utilisation of Roasted Guar Korma as alternative for fishmeal and soybean meal in shrimp diets by Eric De Muylder1, Diana Pablos2, Milivoj Rubcic2 and Leon Claessens3
R
oasted Guar Korma is a high protein raw material, obtained after extraction of Guar gum from the seeds of the leguminous plant Cyamopsis tetragonoloba. It is cleaned and roasted after the gum extraction to remove anti-nutritional factors present in korma, such as trypsin inhibitor, improving its nutritional values and total digestibility. The product is obtained without added
soybean meal and 50 per cent Chilean Fish meal to obtain the same protein levels in all feeds.
observe that the feed with 10 RG has a little less growth, and this difference is statistically different.
Shrimp trial
The shrimp trial was conducted at the CreveTec-AFT Research station in Venray. The trial started with shrimp (Litopenaeus vannamei, Shrimp Improvement Systems) of +2,5 g and lasted for 4 weeks. There are 4 replicates for each diet, so 12
Table 1: Composition of Roasted Guar Korma Crude Protein
55%
Crude Fat
7%
Moisture
6%
Crude Fiber
3%
Ash content
6%
Amino acids (as % of crude Protein) Methionine
1,105%
Cysteine
1,278%
Lysine
4,208%
Threonine
2,817%
Arginine
12,744%
Isoleucine
2,915%
Leucine
5,367%
Valine
3,357%
Histidine
2,450%
Phenylalanine
3,734%
Table 2: Composition of test diets REF
RG5
RG10
Chilean fish meal
25
22,5
20
Squid liver powder
4
4
4
Hemoglobin powder
2
2
2
34,8
34,8
34,8
20
17,5
15
Raw Material :
chemicals or preservatives and is completely GMO free, which can be an important factor to replace soybean meal. Roasted Guar Korma is thus a competitive alternative for soybean meal, but there is little information about its use in Aquafeeds.
Experiment:
3 experimental diets were produced: one reference diet, a diet with 5 per cent Roasted Guar Korma and a diet wiht 10 per cent Roasted Guar Korma. Feeds are produced with a pellet mill on a 2 mm die, using preconditioning with steam (>90째C) and postconditioning (>90째C) during 20 minutes. Roasted Gur Korma replaced 50 per cent
tanks of 150 l in total. Each tank received 30 shrimp. All tanks are connected to a bigger tank. This way, all tanks have the same water quality. Water quality in the big tanks is maintained with bioflocs. Feed gift is adapted daily according to the average weight of shrimp, biomass and expected growth. Each week, shrimp were counted and weighed together to have average weight and total biomass.
Results:
Initially, growth of feeds with RG were showing better growth, but this did not continue during the whole 4 weeks. We can
10 | INTERNATIONAL AQUAFEED | November-December 2014
Wheat flour Soybean meal
5
5
5
Soyalecithin
Rice bran
1,2
1,2
1,2
Fish oil
0,9
0,9
0,9
Wheat Gluten
5
5
5
Premix
2
2
2
5
10
100
100
100
Crude Protein
38,26
38,26
38,26
Lipids
7,08
7,08
7,08
Roasted Guar Korma Total