A study was conducted to evaluate the effect of phosphorus supplementation in the

formulated fish diet on carcass quality of Nile tilapia in net-cages suspended in fertilized

earthen ponds. In the experiment 3% di-calcium phosphate (DCP), 3% triple supper

phosphate (TSP) and 7% 16:20 inorganic fertilizer were added as phosphorous sources to

three diets containing fish meal as main protein ingredient. Feeding tilapia in net-cages

with these diets significantly (p<O.OS) improved the carcass quality and bone

phosphorous content of Nile tilapia over fish fed with same diet without phosphorous

supplementation and fish given no feed. The final body composition and bone

phosphorous content of Nile tilapia fed with DCP, TSP and 16:20 grade fertilizer

supplemented diets were comparable

Lin, C.K.

Little, D.C.

Sarkar, M.R.U.

Yakupitiyage, A.

Aquatic Commons

Bangladesh]. Fish. Res., 8(1), 2004: 19-25 ©BFRI 
Effect of phosphorous supplementation in the formulated fish 
feed on carcass quality of Nile tilapia Oreochromis niloticus L. 
M.R.U. Sarkar1' *,A. Yakupitiyage, C.K. Lin and D.C. Little 
Asian Institute of Technology, Bangkok, Thailand 
1Present address: Department of Fisheries, Ministry of Fisheries & Livestock, Bangladesh 
*Corresponding author 
Abstract 
A study was conducted to evaluate the effect of phosphorus supplementation in the 
formulated fish diet on carcass quality of Nile tilapia in net-cages suspended in fertilized 
earthen ponds. In the experiment 3% di-calcium phosphate (DCP), 3% triple supper 
phosphate (TSP) and 7% 16:20 inorganic fertilizer were added as phosphorous sources to 
three diets containing fish meal as main protein ingredient. Feeding tilapia in net-cages 
with these diets significantly (p<O.OS) improved the carcass quality and bone 
phosphorous content of Nile tilapia over fish fed with same diet without phosphorous 
supplementation and fish given no feed. The final body composition and bone 
phosphorous content of Nile tilapia fed with DCP, TSP and 16:20 grade fertilizer 
supplemented diets were comparable. 
Key words : Phosphorus, Di-calcium phosphate, Triple super phosphate, Carcass quality, 
Bone phosphorus 
Introduction 
Phosphorus is one of the most essential minerals for fish growth and bone 
mineralization which function primarily as structural component of hard tissues e.g., 
bone, exoskeleton, scale and teeth. Effects of dietary phosphorous deficiency in fish have 
been found mainly to be loss of appetite, reduced growth and head and skeletal 
deformities and under extreme circumstances affect bone formation and lead to death of 
fish (LaB 1979). In semi-intensive culture system the natural food alone usually may 
satisfy all phosphorous requirements of fish to support slow growth rate and to avoid 
gross phosphorous deficiency symptoms. However, in intensive and semi-intensive 
aquaculture system farmers uses supplementary diets to obtain better fish growth, which 
may be deficient in phosphorus or contain in an unavailable form to fish. Then addition 
of phosphorus in supplementary diets may be more appropriate to obtain improve 
carcass quality and better fish growth. 
The aim of the present study was to evaluate the effect of supplementation of di-
calcium phosphate (DCP), inorganic fertilizer triple super phosphate (TSP), and 
inorganic fertilizer 16:20 (16:20 grade fertilizer contains 16 percent N and 20 percent 
M.R.U. Sarkar eta/. 
P 20 5) as phosphorus sources in the formulated fish feed on carcass quality of Nile tilapia 
( Oreochromis niloticus). 
Materials and methods 
The study was conducted for a period 60 days in 15 net-cages each measuring 2.0 m 
x2.0mxl.Om suspended in three fertilized earthen ponds each measuring 200 m2 at the 
campus of Asian Institute of Technology, Bangkok, Thailand. Five treatments including 
one non-feed treatment with three replicates each were tested in a randomized complete 
block design (RCBD). Four iso-nitrogenous and iso-caloric experimental diets were 
formulated and prepared. Di-calcium phosphate (DCP), Triple supper phosphate (TSP) 
and grade 16:20 fertilizer were supplemented at rates 3, 3 and 7% respectively in three 
diets as phosphorus sources. In treatment 3, 4 and 5 fish were fed with 3% DCP 3% TSP 
and 7% grade 16:20 fertilizer supplemented diets respectively. In treatment 2 fish were 
fed with phosphorous non-supplemented diet and in treatment 1 fish were given no feed. 
All sex reversed male Nile tilapia were used in the experiment and stocked with 25 fish 
per net-cage. The initial and the final individual length and weight of fishes were 
measured and recorded. For the analysis of initial carcass proximate composition and 
bone phosphorus thirty fishes were sacrificed and for the analysis of final carcass 
proximate composition and bone phosphorus fifteen fishes per replicate were also 
sacrificed at the end of the experiment. Earthen ponds were fertilized one week before 
stocking of fish and after that regularly weekly basis with inorganic fertilizer at the rate 
of 4-kg Urea-N/h/day and 2 kg TSP-P/h/day. Composition, nutrient and energy content 
of diets used in the experiment are given in Table 1. 
Table l. Composition, nutrient and energy content of experimental diet (g/lOOg dry weight basis) 
Ingredients DIETS 
1 2 3 4 
Soybean meal 60 60 60 60 
Fish meal 5 5 5 5 
Cassava starch 29 26 26 22 
Corn oil 4 4 4 4 
Vitamin premix 2 2 2 2 
DCP1 0 3 0 0 
TSP2 0 0 3 0 
16:203 0 0 0 7 
Total 100 100 100 100 
Proximate composition 
%Dry mater 91.01 89.82 90.12 89.63 
%Protein 31.52 31.83 32.44 31.66 
%Lipid 5.02 4.97 5.11 5.07 
% Crude fiber 4.99 7.89 8.53 6.62 
%Ash 5.78 8.65 8.03 8.68 
%NFE 52.69 46.65 45.89 47.97 
20 
Carcass quality of Nile tilapia 
% Phosphorus 
Gross energy (kj/g) 
P.E ratio (mg/kj) 
0.57 
18.68 
16.87 
1.14 
17.65 
18.01 
1.18 
17.74 
18.28 
1.15 
17.91 
17.67 
1 DCP = Di-calcium phosphate 2 TSP = Triple super phosphate 316:20= A 16: 20 grade fertilizer contains 16 
percent Nand 20 percent P20 5 
In the experiment fish were fed at the rate 3% of body weight (dry feed/wet fish 
weight) twice in a day (50% in the morning between 9.00-10.00 a.m. and rest of the 50% 
in the evening between 5.00- 6.00 p.m.). The feed was given in feeding trays suspended 
in water column. The ration was adjusted biweekly intervals according to batch weight 
after every sampling. 
Water samples were taken at weekly and biweekly intervals and analyzed for 
assessing temperature, dissolved oxygen, pH, ammonia, nitrogen, total alkalinity, total 
phosphate, nitrite, total suspended solid (TSS), chlorophyll-a_,_ phaeophytin-a and 
plankton biomes. 
Proximate composition of ingredients, diets and fish carcass were analyzed 
according to the analytical methods of AOAC (1984) and phosphorous were analyzed by 
molybdate-vandate and spectrophotometric ( 420nm) method. 
To test significance of treatments at 0.05 confidence level (p<0.05) on the mean 
final carcass composition and bone phosphorous, the multi-factor analysis of variance 
CANOVA) and paired t-test was used. The Mstatc statistical software package was used 
for this purpose. 
Results 
Proximate composition of fish body carcass 
The initial and final proximate composition of fish cm:cass in different treatments 
reflected the significance alteration in proximate composition. The initial and final 
mean proximate compositions of fish carcass are given in Table 2. 
Table 2. The initial and final mean proximate composition offish carcass(± S.E n=3) 
Composition Initial Final composition in treatment 
1 2 3 4 5 
%Moisture 78.67±1.13 79.39±0.28 75.83±0.46 74.77±1.13 75.56±1.81 76.10±0.83 
%protein 60.28±0.55 62.61 d±0.22 65.23c±0.33 67.12"±0.49 66.18b±0.59 66.50b±0.56 
%Lipid 9.56±0.42 9.60d±0.27 16.12"±0.51 15.48h±0.28 15.22b±0.40 15.51 h±0.30 
%Ash 17.51±0.62 21.55±0.60 15.45±0.37 16.66±0.58 16.81±0.67 19.26±0.36 
**Figures m the same row havmg the same superscript are not significantly different (p>0.05) 
21 
M.R.U. Sarkar et al. 
Final carcass crude protein content of fish in different treatments ranged from 62.61 
to 66.50% with means of 62.61%±0.22, 65.23%±0.33, 67.12%±0.49, 66.18%±0.59 and 
66.50%±0.56 in T 1, T 2, T 3 T4 and T 5 respectively. Carcass protein difference among the 
treatments were significant (p < 0.05). The highest carcass protein content was in 
treatment 3 (DCP) and the lowest was in treatment 1(Non-feed). Final carcass protein 
content of fish fed with DCP, TSP and 16:20 supplemented diets were comparable. 
Carcass crude lipid content ranged from 9.60 to 16.12% and the lowest crude lipid 
content was in fish given no feed. Carcass lipid content differed significantly (p<0.05) 
among the treatments. Ash content in fish carcass ranged from 15.45 to 21.55 % in 
different treatment the highest ash content was in non fed fish. Comparison between 
initial and final carcass protein and lipid level in different treatment is shown in Fig. 1 
68 
66 
·g 64 
62 Eb I 
o' 60 i 
58 i 
56 
20 
17 
! 14 
' ~ I I 
81 
i 
sl 
~ Initial Carcass 
Tl T2 T3 T4 T5 
Treatment 
! D Initial Carcass 
, Ci Final Carcass 
Tl T2 T3 
Treattnent 
T4 TS 
Fig. 1. Comparison between initial and final carcass protein and lipid level in different treatments 
Phosphorous level in fish carcass and vertebrae bone 
The mean value of phosphorous content in initial and final fish carcass and bone are 
summarized in Table 3. 
22 
Carcass quality of Nile tilapia 
Table 3. The initial and final mean phosphorous content of fish carcass and bone(± S.E) 
Initial Final composition in treatment 
1 2 3 4 5 
Carcass 
%Ash 17.58±0.16 21.55±0.06 15.45±0.37 16.66±0.58 16.81±0.67 19.26±0.36 
%Phosphorous 2.34±0.03 2.54b±0.06 2. 69•b±0.06 2.95"±0.06 2.85"b±0.16 2.81 ab±0.05 
Bone 
%Ash 44.02±0.43 58.77±2.06 46.54±1.19 50.98±0.90 50.71±0.80 50.28±0.51 
%Phosphorous 5.78±0.05 6.19c±0.03 7.32b±O.l8 7.873±0.15 7.783±0.06 7.773±0.35 
** Frgures m the same row havmg the same superscnpt are not srgmficantly drfferent (P <0.05) 
Carcass phosphorous content of fishes ranged from 2.54 % to 2.95% in differem 
treatments. The highest phosphorous content was in carcass of fish fed with DCP 
supplemented diet and the lowest was in fish given no feed. Phosphorous content in 
vertebra bone of fishes ranged from 6.19% to 7.87 % and meal values of vertebra bone 
differed significantly (p<0.05) among the treatments. The highest phosphorous content 
was in carcass of fish fed DCP supplemented diet and lowest was in fish given no feed. 
Carcass phosphorous and vertebrae bone phosphorous content of fishes fed DCP, TSP 
and 16:20 fertilizer supplemented diet were comparable. Comparison between initial and 
final carcass and bone phosphorous are shown in Fig.2. 
2 
1.5 
Tl 
Tl 
I
' c) Initial CarcaSS 
C Final Carcass 
T2 
Treatrn.ent 
T2 T3 
T4 
Treatment 
T5 
T4 T5 
Fig. 2. Comparison between initial and final carcass and bone phosphorous 
level in different treatments 
23 
M.R.U. Sarkar er al. 
Water quality parameters 
The water quality parameters analyzed at the start of the experiment and during the 
whole experimental period are summarized in Table 4. ~rater quality parameters in 
different ponds was almost uniform and within suitable range for fish culture. 
Table 4. Mean value of water quality parameters during whole experimental period 
Pond DO pH Temp NH4-N Alkalinity TSS Chlo-a 
(mg(l) (mg/1) (mg/1) (mg/1) (!-lg/1) 
1 2.69±0.3 7.64±0.3 29.22± 0.45 0.62+ 0.02 237+ 5.28 43.91+ 16.43 64.38+0.75 
2 2.59 ±0.2 7.31+0.3 29.16+ 0.39 0.60+0.02 230+ 3.12 31.52+ 13.23 55.20+ 2.67 
3 2.79±0.3 7.39±0.5 29.24±0.39 0.72+ 0.01 239+ 13.23 43.46+ 16.93 66.30+1.91 
Discussion 
In the present study Nile tilapia fed diets, supplemented with 3% di-calcium 
phosphate (DCP), 3% triple super phosphate (TSP), 7% inorganic fertilizer 16:20 as 
Phosphorus sources. The supplementation of phosphoms in diets reflected the 
significant alteration in proximate composition of final fish carcass of tilapia. The 
highest body protein level was in fish fed with DCP supplemented diet and the lowest 
body protein level was in phosphoms non-supplemented diet. Body protein and lipid 
content offish in DCP, TSP and 16:20 supplemented diets were resembling. The highest 
lipid content was in phosphorus non-supplemented diet. Murakami (1970, cited in Lall 
1979), Hung (1989) and Wee and Shu (1989) found that supplementation of phosphorus 
in the diet causes decrease in the lipid content of the muscle and viscera and increase in 
muscle protein of fishes. Phosphorus supplementation in diets influenced the carcass 
and bone ash content and phosphorus level of fishes. The lowest ash content and 
phosphorus level in body carcass and vertebrae bone was found in fishes fed with 
phosphorus non-supplemented diet. Higher and coinciding ash content and phosphorus 
level were found in carcass and bone of fish fed with DCP, TSP and 16:20 supplemented· 
diets respectively. It indicates that there was a positive relationship between dietary 
phosphorus level and ash content in carcass and bone as well as phosphorus level in 
carcass and bone. Similar results also found by Robinson et al. (1987) and Haylor et al. 
(1988). Phosphorus supplementation also affected the phosphorus deposition in fish 
body carcass. The lowest phosphoms deposition was in fish fed with phosphorus non-
supplemented diet. Higher and alike body phosphoms deposition observed in fish fed 
with DCP, TSP and 16:20 supplemented diets. It also indicates that phosphorus 
availability from DCP, TSP and 16:20 to tilapia were almost same. 
Conclusions 
In view of the above study it may be concluded that, phosphorus supplementation in 
the formulated fish feed play significant role on fish carcass quality and bone 
24 
Carcass quality of Nile tilapia 
phosphorous content. Body composition and bone phosphorous content of Nile tilapia 
fed with di-calcium phosphate (DCP), triple super phosphate (TSP) and a 16:20 grade 
fertilizer supplemented diets were comparable. 
References 
AOAC (Association of Official Analytical chemists), 1984. Official methods of analysis of the 
Association of Official Analytical Chemists, 14'h Edition. Association of Official Analytical 
Chemists, Inc., Arlington, Virginia, USA. 
Haylor, G.S, M.C.M. Beveridge and K. Jauncey, 1988. Phosphorus nutrition of juvenile 
Oreochromis niloticus. In: The second international symposium on tilapia in aquaculture. 
ICLARM Conference Proceedings (eds. R.S.V Pullin, T. Bhukaswan, K. Tonguthai and J.L. 
Maclean). Department of Fisheries, Bangkok, Thailand and ICLARM, Manila, Philippines. 
pp. 341-345. 
Hung, J.W., 1989. Evaluation of soybean mean as a supplementary feed for red Nile tilapia (0 
niloticus x 0. nissanvucys) M.Sc. Thesis AE-89-66. Asian institute of Technology, Bangkok, 
Thailand. 96 pp. 
Lall, S.P., 1979. Chapter 5. The Minerals. In: Fish nutrition (ed. J.E. Halver). Academic press. pp. 
220-252. 
Robinson, E., D. Labomascus, D.B. Brown and T.L. Linton, 1987. Dietary calcium and 
phosphorus requirement of 0. aureusreared in calcium-free water. Aquaculture~ 64 267-276. 
Wee, K.L. and S.W. Shu, 1989. The nutritive value of boiled full-fat soybean in pelleted feed for 
Nile Tilapia. Aquaculture, 81:303-314. 
(Manuscript received 9 December 2003) 
25 


Effect of phosphorous supplementation in the formulated fish

feed on carcass quality of Nile tilapia Oreochromis niloticus L.

http://aquaticcommons.org/17675/1/BJFR8.1_019.pdf

Effect of phosphorous supplementation in the formulated fish feed on carcass quality of Nile tilapia Oreochromis niloticus L.

Abstract

Similar works

Full text

Available Versions

Aquatic Commons