//Nutrient requirements of gold fish

Nutrient requirements of gold fish


About gold fish

Since time immemorial, gold fish has been one of the most sought after ornamental fish by aquarium fish keepers throughout the world. It is considered to be the most popular ornamental fish due to its many variations such as colour, finnages, tail, shape, size and body structure. May aquarist believe that a community aquarium tank is not a complete ones unless it is having few varieties of gold fish. Though similar to golden carp (Carassius carassius), gold fish lacks barbels and a dark spot at the base of each scale. It is one of the oldest known aquarium fish. It was developed in China more than 1000 years ago. There are about 100 varieties of gold fish that appeals to a wide range of aquarium fish lovers. The common gold fish varieties are shubunkin, wakin, jikin, ryukin, fantail, demekin, tosakin, comet, veil tail, moor, oranda, red cap, lion head, phoenix, pompon, telescope eye, celestial, bubble eye, meteor, golden orfe, etc.

Nutrient requirements and potential feeds

For successful rearing of gold fish, it is reported that gold fish require about 40% protein and 4.0 kcal /g energy. Based on the nutrient requirement of this fish as reported earlier, four iso-proteinous (40.0 % crude protein) cost-effective nutritionally balanced practical diets (based on chicken liver, lean prawn meal, mussel meal or squid meal as main dietary protein sources) were formulated and compared with the two commercial diets (59.0 % crude protein) procured from local market. The ingredients and the proximate compositions of the formulated and commercial diets are given in Tables 2 and 3. The diets were fed to the gold fish fingerlings (4.61±0.43 g) for a period of 30 days at 10 per cent of their body weight. The experiment results indicated no significant differences in growth and nutrient utilization of fish fed formulated diets and the commercial diets (Table 4). However, the costs of the formulated diets were found to be much cheaper (Rs 80-300/kg) than the commercial diets (Rs1100-3500/kg) used in the experiment. From the growth performance and economics of fish rearing it is concluded that the lean prawn meal based diet is the best and suggested for use for rearing the gold fish.

With each of the formulated feeds, more than 100% growth was achieved within one month of rearing. Hence, aquarium fish traders can rear small fish for about one month using one of the formulated feeds, obtain fish weighing twice or more the original weight and sell them at a much higher price as bigger aquarium fish always command better prices than smaller ones. The equipment (hand pelletizer) used to prepare the feeds used in the present study is readily available to hobbyists and small scale aquarium fish traders.

Study of Freshwater

Table 2. Ingredient composition of formulated ornamental fish feeds used for growth performance study on gold fish, Carssius auratus.

Ingredient composition (% dry matter)

Ingredients

T-l

(Chicken liver based)

T-2

(Prawn meal based)

T-3

(Mussel  meal based)

T-4

(Squid meal based)

Chicken liver

25

Prawn meal

25

Mussel meal

35

Squid meal

20

Fish meal

25

25

25

25

GN Cake

20

20

20

25

Wheat bran

10

10

10

10

Maize

10

10

10

10

Mineral & Vit. Mix

3

3

3

3

Oil

2

2

2

2

Binder

5

5

5

5

Red cap gold fish Common Gold fish

Table 3. Proximate composition of the prepared and market procured ornamental fish diets used for growth performance of gold fish, Carassius auratus.

Feeds

Dry Matter

Total Ash

Acid Insol. Ash

Crude Protein

Crude Fat

Crude Fibre

Energy (Kcal / g of feed)

Chicken Liver based diet

2.50

17.20

1.00

40.50

7.50

2.00

4.33

Prawn Meal based diet

93.10

19.80

5.20

40.00

3.50

3.20

3.96

Mussel Meal based diet

92.20

15.56

2.40

40.40

10.00

1.50

4.55

Squid Meal based diet

91.90

16.10

3.00

40.15

5.50

1.00

4.31

Tubifex Worm diet

92.30

18.95

2.00

59.20

9.00

0.01

4.71

Brine shrimp Flake diet

93.50

13.80

0.20

59.00

13.80

1.50

4.89

Table 4. Comparative growth performance and costs of six gold fish, Carassius auratus feeds.

Parameters

OFF-I

(Chicken liver based)

OFF-II

(Prawn meal based)

OFF-III

(Mussel meal based)

OFF-IV

(Squid meal based)

C-1

(Tubifex worm)

C-2

(Brine Shrimp Flake)

Weight increment (g)

6.30 b

5.73 b

6.72 b

9.26 a

6.54 b

FCR

1.860 a

1.890 a

1.830 a

1.460 a

1.720 a

SGR

2.810 a

2.835 a

2.706 a

3.781 a

3.171 a

PER

1.343 ab

1.322 ab

1.364 a

1.164 bc

0.995 c

Cost/kg of feed (Rs)

88.75

58.70

147.85

3500

1150

Cost of production for  1 kg biomass

177.50

110.35

269.08

5110.00

1978.00

C.P.(%)

40.50

40.00

40.15

59.00

59.00

Source : ICAR – Central Coastal Agriculture Research Institute

Source