Vermiculture in Egypt: - FAO - Regional Office for the Near East and

the cost of fish-keeping, but also better results of that culture (Kostecka and Paczka,
2006).
Three meals were formulated from the earthworm (Endrilus eugineae) and maggot
(Musca domestica) and fish (Engraulis encrosicolus). These meals were evaluated as
a potential replacement for fishmeal. This is because fishmeal could be very
expensive at times. The three meals were used in feeding the catfish (Heterobranchus
isopterus) for 30 days. On the basis of weight increment, the best growth performance
was produced by maggot meal. It was followed by earthworm and fish meals,
respectively. Based on food conversion ratio maggot meal was again the best,
followed by earthworm and fish meals respectively. The importance of supplementary
feeding was evidenced in the higher weight increment in fish that were fed than those
that were not fed. Maggot and earthworm meals could therefore be a whole or partial
replacement for fishmeal. The difficulty in the harvesting or rearing maggots and
earthworms may however reduce this potential (Yaqub, 1991).
The use of vermicompost in pisci-culture is gaining its increased recognition for the
conservation of energy and optimum but economical utilization of available resources
with simultaneous pollution control. Vermicompost is hazard free organic manure,
which improves quality of pond base and overlying water as well as provides
organically produced aqua crops. The additions of manures affect the relative
abundance of the plankton and their community structure in aquatic system. Proper
combinations of inorganic nutrients (NPK) are the major factors that influence the
growth and production of plankton in a pond. Vermicompost contains all the major
organic nutrient components of N, P and K along with some necessary micronutrients
for plankton growth (Table 6.4).
In aquaculture industry, capital investment apart, there are also operating expenses,
mainly for seed, fertilizer, feed and labors. Among those, the cost of feed and
fertilizer constitute about 70% of the total expenses. For this reason there is need for
searching out chapter sources for feed and fertilizer. So, this is particularly significant
in developing nations, where fish farmers are unable to buy costly fish feed and
chemical fertilizer vermicompost forms an abundant alternative natural resource for
less expensive manure and fish feed for higher fish yield. However, the amount of
available nitrogen and phosphorus from vermicompost is less when compared with
conventional fertilizers and research should be oriented to increase its nitrogen and
phosphorus concentration through alteration of substrate composition.
Table 6.4. Different nutrient concentration in manure and fertilizer applied (average
value of triplicate sample analyzed)
Parameters
Available N
(mg·g -1 )
Available P
(mg·g -1 )
Available K
(mg·g -1 )
Dry weight of fertilizer
and manure used (g)
Diammonium phosphate (DAP) 18 ± 0.07 46 ± 0.05 Nil 3.04
Vermicompost 1.5 ± 0.05 1.4 ± 0.08 1.0 ± 0.05 99.0
Compost
Souce: Chakrabarty et al, (2009).
1.0 ± 0.08 0.55 ± 0.09 1.0 ± 0.05 252.0
Sample of soil, compost, vermicompost and DAP were analyzed for available P, N
content as well as for organic carbon. The dry weights of the fertilizer and manure
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