A fertilizer experiment was conducted outdoor plastic tanks to study the effect of different fertilizers on survival and growth of common carp (Cyprinus carpio. L) fingerlings (0.88 ± 0.09 g) divided into 9 treatment groups of 3 replicates for 60 days, Individual weight gain and survival rates were compared among a control system. Three treatments were manured at every 7 days with cow dung, poultry manure, and compost at 0.26 kg/ m3, 0.39 kg/ m3 and 0.52 kg/ m3 dose. The survival rates were observed in all treatments, ranging from 60 %, 44.43 %, and 22.23% in poultry manure, cow dung, and compost respectively. The nutrients contents in manures were higher in poultry manure and lower in cow dung and compost. Weight gain of common carp stocked in poultry manures system was reported the significantly higher growth (2.06±0.33 g) than other treatments. The highest SGR (1.66%) was recorded in poultry manured system. The lowest SGR was observed in cow dung fertilized system (0.22%) while it was 0.50% in compost system. The results suggest that application rate of 0.52 kg/ m3 at every 7 days seems to be the most suitable for common carp manured with poultry litter, through maintenance of better water quality to enhance the greater abundance of plankton biomass in the system.
The common carp (Cyprinus carpio L.) belongs to the family Cyprinidae, the largest freshwater teleost family (Nelson, 1994) and is probably the oldest and most extensively cultured fish species in the world. Common carp is one of the most widely cultured species in India. This species is omnivorous, hardy and tolerant of wide fluctuations in environmental conditions and is preferred for culture by many farmers. Aqua farmers in India fertilize carp culture ponds to enhance fish yield (Sharma and Olah, 1986), mainly through mineralization, microbial degradation (Zhu et al., 1990) and thus increased natural food production. It plays an important role in the growth of fish under pond conditions (Lovell, 1989). Use of commercial feed is prohibitively expensive, effectively excluding resource poor aqua farmers from adopting this measure to increase production. The FAO/AADCP Regional Expert Consultation has emphasized the need for a greater understanding of the role of natural food organisms in semi-intensive farming based systems that optimize pond fertilization (NACA/FAO, 2000). Judicious organic fertilization of fish ponds can eliminate the need for supplementary feeding (Moav et al., 1977). Organic matter is the main source of nutrients in aquaculture ponds. It is widely contended that the biological productivity in aquaculture ponds is often limited by the nutrients in least supply. As nutrients play an important role, fertilization has assumed a greater role in supplementing nutrient deficiency as well as stimulating plankton production functioning through autotrophic and heterotrophic pathways (Schroeder, 1974; Debeljak et al., 1990; Jana and Sahu, 1994; Jhingran, 1995). Das and Jana, 1996 also emphasized like in many studies under tropical and temperate conditions, (Wolhfarth et al., 1980; Barash et al., 1982; Wolhfarth and Hulata, 1987; Schroeder et al., 1990; Milstein et al., 1995).The purpose of this study is to evaluate the effect of different types of fertilizers on survival of common carp fingerlings; to examine the response of different types of fertilizers on growth of common carp fingerlings and to assess the effect of fertilization on water quality.
Materials and Methods
The fish used in this study were procured from Keri Sattari hatchery, Goa state, India. The experiments were conducted in 30 outdoor rectangle plastic tanks (capacity 75 L) in the Central Institute of Fisheries Education, Versova, Mumbai, India New Campus hatchery. 2 cm layer of loamy soil was placed on the bottom of each tank, which was then filled with 75 L of groundwater, seven days prior to stocking. This interval after manure application is a prerequisite for establishing satisfactory environmental conditions for optimum plankton production in tanks (Chakrabarti and Jana, 1991). Four hundred fifty common carps (0.88 ± 0.09 g), were equally distributed to each tank (15 fish / tank) to study the effect of rate of application of different fertilizers i.e. cow dung, poultry manure and compost on its growth and survival. Fish were treated for 60 days (February – April, 2012), nine treatments, with following fertilizers application:
(1) Cow dung @ 0.26 kg/m3 every 7 days interval (C1);
(2) Cow dung @ 0.39 kg/ m3 every 7 days interval (C2);
(3) Cow dung @ 0.52 kg/ m3 every 7 days interval (C3);
(4) Poultry manure @ 0.26 kg/ m3 every7 days interval (P1);
(5) Poultry manure @ 0.39 kg/ m3 every7 days interval (P2);
(6) Poultry manure @ 0.52 kg/ m3 every7 days interval (P3);
(7) Compost @ 0.26 kg/ m3 every 7 days interval (Co1);
(8) Compost @ 0.39 kg/m3 every 7 days interval (Co2);
(9) Compost @ 0.52 kg/m3 every 7 days interval (Co3) and
(10) A control treatment in which a commercial pelleted diet was used as feed (C).
Three tanks were randomly assigned for each treatment. The application rates of the manures correspond to 1,300-3,900 kg/ha. The high organic load was used in view of the high manuring rate (initial dose of 10,000 kg/ha and subsequent application of 5,000 kg/ha), recommended for nursery ponds in India (Jhingran, 1995). Nutrients included in manure were estimated by C, H, N, S analyser (elementer verio micro cube) in Aquatic Environment Management laboratory, Central Institute of Fisheries Education, Old Campus, Mumbai.
The manures were collected from local dairy and poultry farms, and allowed to get decomposed for 10 days prior to their application. For compost preparation, green plant leaves collected from trees were placed in wet soil for two weeks period to get them decomposed as compost and then it was used as fertilizer. No manure was added to the tanks in the control treatment, where a commercial pelleted feed containing 32% crude protein, 4% crude fat, 5% crude fibre, 10% crude ash, 9% moisture and 31% nitrogen free extract, was given daily of 5% of the body weight of stocked fish daily. Dry feeds were not applied to any other treatment and the fish fed on naturally grown food. For estimating the different water parameters, when samples were collected weekly at 10:00 AM from the tanks in the sterilized bottles. The temperature, pH and free CO2 were measured at the site itself and for dissolved oxygen the samples of water were fixed at the site and analyzed in Central Institute of Fisheries Education laboratory. For other parameters like total alkalinity and hardness, water was collected in one liter glass sterilized bottles and analyzed in laboratory. The water samples were analyzed following the methods of APHA (1995) and (Saharan et al., 2001). The weight of the fish was recorded in the beginning of the experiment and afterwards every fortnightly during the culture period. Five random samples of 15 fish from each tank were collected. Dead fish were removed, they were not replaced during the course of study, and differences between the number of fish stocked and the number of fish at harvest were used to calculate percent mortality in each treatment. Fish were harvested after 60 days period and weighed. The growth rate of fish was calculated according to Wootton (1989) as follows:
Absolute Growth (AG)
AG was measured by using the following formula:
AG = FL – IL
(FL) Final length and (IL) Initial Length
AG = FW – IW
(FW) Final Weight and (IW) Initial Weight
Relative Growth (RG)
RG = AG
RG = Relative Growth
AG = Absolute Growth
IW = Initial weight (g)
Per Day Increment
It is per day growth in terms of length or weight
Per Day Increment = Absolute Growth
Experimental Period (days)
Specific Growth Rate
LnW2 – LnW1
SGR = ————————- X100
LnW2 = log of final weight (g)
LnW1 = log of initial weight (g)
T = time period (days)
Water temperature was recorded between 18 to 28 oC during 60 days duration. The average of pH values varied between 7.3 to 7.7. The dissolved oxygen content of all the experimental water samples was recorded within the range of 7.2 to 10.5 mg/l. Free carbon dioxide in all water samples was absent. The total alkalinity was found in the water samples towards higher side. The observed values in the present study were as follows; in cow dung manure system it ranged from 214 mg/l to 264 mg/l, in poultry manure the range was from 218 mg/l to 266 mg/l, while in compost it fluctuated from 134 mg/l to 180mg/l. In control system, it varied from 275 mg/l to 298 mg/l. The water hardness was recorded within the range of 200 to 320 mg/l. Comparatively high amounts of C, N, and S were observed in poultry manure while they were in lesser concentrations in cow dung and compost (Table 1).
Table 1: Nutrients percentage in the different manures
The initial body weight among the experimental groups varied from 0.75±0.01 to 1.03 ± 0.05 g, and the initial length ranged from 39.80 ± 1.22 to 42.33 ± 0.50 mm; while the maximum body weight was recorded in poultry manured system ranging from 1.94 ± 0.41 to 2.29 ± 0.33 g, on the other hand, the length ranged from 52.27 ± 3.06 to 52.97 ± 0.40 mm (Fig. 1).
Fig. 1: Weight of common carp fingerlings manured with poultry litte
The highest survival rate was observed in poultry manure (60 ± 20 %) and the lowest survival rate was in compost manure (17.76 ± 13.85 %) The survival rate in cow dung manure ranged between (19.96 ± 11.54 to 44.43 ± 13.89 %) which is higher than compost but lower than poultry manured system. The maximum weight gain of common carp was recorded in poultry manured system. The highest specific growth rate (1.66 %) was recorded in poultry manured system. The lowest specific growth rate was observed in cow dung fertilized system (0.22 %) Table 2.
Table2: Means± SD initial weight, harvest weight, specific growth rate (SGR) and survival rate at 8 week growth period (February-April, 2012) of common carp fingerlings reared in plastic tanks
|Factors||Cow dung 1||Cow dung 2||Cow dung 3||Poultry 1||Poultry 2||Poultry 3||Compost 1||Compost 2||Compost 3|
|Manure application rate(kg/m/7days)||0.26||0.39||0.52||0.26||0.39||0.52||0.26||0.39||0.52|
|Initial weight (g)||0.84 ± 0.22||0.90 ± 0.07||0.98 ± 0.06||0.71 ± 0.23||0.80 ± 0.07||0.75 ± 0.01||0.97 ± 0.06||1.03 ± 0.05||0.84 ± 0.09|
|Harvesting weight (g)||0.96± 0.09||1.07 ± 0.06||1.16 ± 0.13||0.96 ± 0.08||0.99 ± 0.06||1.02 ± 0.07||1.94± 0.41||1.96 ± 0.26||2.29 ± 0.33|
|Absolute growth (g)||0.12||0.17||0.18||0.25||0.19||0.26||0.98||0.93||1.45|
|Relative Growth (g)||0.1468||0.1889||0.187||0.3538||0.2385||0.3497||1.0102||0.8968||1.7155|
|Per day increacment (g)||0.0021||0.0028||0.0031||0.0042||0.0032||0.0044||0.0163||0.0154||0.0241|
|Survival rate (%)||19.9± 11.5||26.6 ± 6.6||44.4± 13.8||17.8 ± 13.8||19.9 ± 11.5||22.2 ± 3.8||44.4 ± 13.8||55.6 ± 21.4||60 ± 20.00|
Discussion and Conclusion
Temperature plays an important role in regulating metabolic rate of fish. The air and water temperatures observed during entire experimental period were within the range of 24 -37oC for air and 18 – 28oC for water respectively. Although Cooper (1987) and Jenkins et al. (1993) reported the optimum water temperature for common carp as 18 oC yet the fish can survive extended exposure to temperature above 32 oC and maximum range up to 36-41 oC. The best growth is obtained at water temperature range of 23-30°C. The fish can also survive in cold winter periods. The pH of culture water is one of the important indices of aquaculture yield. The pH of the water in which common carp fingerlings were reared, which was within the acceptable range of 6.5 to 9.0 for common carp culture system, (FAO, 2006). Jatindra et al. (2006) reported that water quality parameters varied highly under the application of different doses of fertilizers as well as under passage of time period. Water temperature and pH ranged from 28.5 – 30°C and 7.5 to 8.22 in different treatments respectively. The concentration of dissolved oxygen in pond water varied between 2.8 and 18.8 mg/l depending upon the rate of application of fertilizer dose. Higher dose of fertilizer, i.e., its application more than requisite nutrients budgeting is directly proportional to the availability of dissolved oxygen and carbon dioxide during light and dark hours respectively. This phenomenon may cause fish mortality before sun rise .The dissolved oxygen level in this present study ranged from 7.2 to 10.5 mg/l, which was within the normal range of ( 3 – 5 mg l-1) required for common carp as reported by FAO, (2006).The common carp can survive in low oxygen concentration (<5mg/l) as well as at super saturation. In the present study, the free carbon dioxide concentration was not detectable. This was due to the continuous aeration in experimental tanks which stripped off carbon dioxide. The total alkalinity of water depicts the measure of its capacity to neutralise the acids, caused by the salts of weak acids. However, it is known that it has a little sanitary significance as the highly alkaline water is usually unpalatable for human consumption but quite productive for fish growth in culture ponds. The total alkalinity in was found in the water samples towards higher side. The observed values, in the present study, were in follows; in cow dung manure system it ranged from 214 mg/l to 264 mg/l, in poultry manure the range was from 218 mg/l to 266 mg/l, while in compost it fluctuated from 134 mg/l to 180mg/l. In control system, it varied from 275 mg/l to 298 mg/l .The highest concentration of alkalinity in control system (fed with pelleted feed) may be due to two times daily feeding, while the fertilized tanks were given only manure dose weekly. The favourable range of alkalinity for fresh water fish culture system is 50 to 275 mg/l, Saharan et al. (2001).The water hardness has been understood to be measure of the capacity of the water for soap precipitation. It is caused by the presence of total concentration of divalent metallic cations like calcium, magnesium, ferrous, and strontium ions etc. in water. In all experimental water samples, the water hardness was recorded within the range of 200 to 320 mg/l. The favourable range of hardness for fresh water fish culture practices is 50 to 275 mg/l. Its strength was in higher amount because the available source of water was ground water coupled with the application of manures for fertilization of culture water.
Growth is the result of a balance between the process of anabolism and catabolism, which occurs in each individual (Bertalanffy, 1938). It can be expressed as the increase in length and weight against time. In aquaculture, growth is generally measured by weight gain. Conducive environment in poultry and compost resulted in significantly better specific growth rate of common carp than cow dung treatment. According to Milstein et al. (2003), common carp as a bottom feeding fish produces a fertilizing effect through a food web that benefits the filter feeding fishes and reduces the application of organic and inorganic fertilizers in the aquaculture practices. It grows rapidly with high protein diet and minimum feed coefficient and it is considered as a target cultured fish, which plays an important key role in pond management. Nandeesha et al. (2001) also noted that the specific growth rates, protein efficiency ratio as well as growth rate were more pronounced in animal and plant based diet as compared to animal based diet. In any given application rate of manure, the poultry manure appeared to be more effective compared to cow dung manured and compost fertilized systems because of the availability of high nutrients in poultry manure, resulted in the high survival rate.
The authors are highly thankful to Dr.W.S. Lakra, Director, Central Institute of Fisheries Education, Mumbai for permitting to carry out the research work and publish this paper. The authors are grateful to Mr. H.B. Jayasiri, Ph.D student in Department of Aquatic Environment Management, Central Institute of Fisheries Education, Mumbai,, India for providing analysis of Data. The authors also appreciate the assistance they provided by Mr. Gashaw Tilahun , PhD student in Department of Aquaculture, CIFE, Mumbai, India .