Saturday, November 23, 2024
|
|
|
മലയാളം
|
|
|
|
Livestock-fish
system
Livestock-fish system includes cattle-fish system, pig-fish system, poultry-fish
system, duck-fish system, goat-fish system, rabbit-fish system. In this practice,
excreta of ducks, chicks, pigs and cattle are either recycled for use by fish or
serve as direct food for fish. Hence, the expenditure towards chemical fertilisers
and supplementary feeds for fish culture is not only curtailed to the barest minimum
but also there is economy of space. Integration of fish culture and livestock farming
is in vogue in many countries and the income realised has been found to be more
than that of exclusive fish farming in ponds.
The main potential linkages between livestock and fish production concern use of
nutrients, particularly reuse of livestock manures for fish production. The term
nutrients mainly refers to elements such as nitrogen (N) and phosphorous (P) which
function as fertilizers to stimulate natural food webs rather than conventional
livestock nutrition usage such as feed ingredients, although solid slaughterhouse
wastes fed to carnivorous fish fall into the latter category.Both production and
processing of livestock generate by-products that can be used for aquaculture. Direct
use of livestock production wastes is the most widespread and conventionally recognized
type of integrated farming. Production wastes include manure, urine and spilled
feed; and they may be used as fresh inputs or be processed in some way before use.
Use of wastes in static water fishponds imposes limitations in terms of both species
and intensity of culture. Stimulation of natural food webs in the pond by organic
wastes can support relatively low densities of herbivorous and omnivorous fish but
not a large biomass of carnivorous fish. These biological processes are also temperature
dependent. The optimal temperature range is between 25-32°C although waste-fed
aquaculture in sub-tropical and temperate zones where temperatures rise seasonally
has also been successful. Processing wastes through organisms such as earthworms
and insect larvae that feed on them and concentrate nutrients to produce ‘live
feeds’ is an alternative approach to raising fish needing high levels of dietary
animal protein. Livestock processing can also provide a wide variety of wastes that
vary from dilute washing water to high value meat and bloodmeal that can be used
as high value fish feeds or feed ingredients. If enough of these types of feeds
are available, high density and intensive production of carnivorous fish species
can be supported. Aquaculture may also provide inputs and other benefits to livestock
production. A variety of aquatic plants e.g. duckweeds and the aquatic fern Azolla
have proven potential as livestock feeds; and invertebrates such as snails
and crustaceans can be used for poultry feeds.
Based on the type of livestock used for integration there are many combinations
in livestock-fish systems. The important ones are discussed below.
Top
|
|
|
|