molluscs, snails (Gastropoda) and mussels (Bivalvia), are an excellent food for
many species of freshwater fish and crustaceans. In rivers, lakes and
reservoirs, molluscs form powerful bottom placers and foulings that are
actively exploited by many cyprinid and other fish.
example, it is shown that bream, Abramis
brama, white bream,
Blicca bjoerkna, common roach, Rutilus rutilus, and carp, Cyprinus
carpio, can eat zebra mussel, Dreissena
polymorpha, of size ranged from 1-2 to 45 mm depending on fish age (Prejs et al., 1990; Nagelkerke
& Sibbing, 1996; Tucker et al., 1996). The real switch to zebra mussels would
be expected in fish of 23–24 cm length (Prejs et al., 1990). Other abundant
freshwater molluscs are Viviparus
viviparus, V. ater, V. contectus and
other viviparous snails. For example, newborn V. ater are eaten by barbel,
Barbus barbus, roach, R. rutilus, rudd, Scardinius erythrophtalmus and tench,
Tinca tinca (Keller & Ribi, 1993),
while adult viviparids (with the relatively hard shell and shell size up to 45
mm) are eaten by all large cyprinid fish with the well developed pharyngeal teeth.
proximate compositions and fatty acid profiles of the freshwater mussels Unio terminalis and Potamida littoralis are compared by
Ersoy & Şereflişan (2010). The crude protein (11,87-11,97 %), lipid
(2,55-1,05 %), ash (1,68–1,61%) and moisture (80,36-81,69 %) contents of U.
terminalis and P. littoralis are
observed. Lipid content in U. terminalis
is found to be significantly higher than in P. littoralis. The percentages of total
saturated fatty acids and total monounsaturated fatty acids are higher in U. terminalis
than in P. littoralis. At the same
time, the corresponding content of total polyunsaturated fatty acids is lower. The
n3-n6 ratio are 1,54-1,40 in U. terminalis and P.
littoralis, respectively. Using these data, Ersoy
& Şereflişan (2010) conclude that freshwater
mussels U. terminalis and P. littoralis are suitable as the healthy food.
Freshwater and Saltwater Molluscs
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acid content in three species of earthworms, cosmopolitan tiger worms, Eisenia foetida, African earthworms, Eudrilus eugeniae, and Indian blue
worms, Perionyx excavatus, are studied by Reinecke et al. (1991). Leucine and
arginine are most abundant among essential amino acids in all three species.
Crude protein content are 66,13 % in E.
foetida, 58,38 % in E. eugeniae,
61,63 % in P. excavatus and 61,00 %
in fishmeal, for comparison. The amino acid profile in four species of
earthworms namely E. eugeniae, Hyperiodrilus
africanus, Alma millsoni and Libyodrilus violaceus, in comparison with E. foetida, is studied by Dedeke et al. (2010). Arginine is most
abundant in four African species and one of the abundant essential amino acids (after
leucine and lysine) in E. foetida. Glutamic
and aspartic acids, among non-essential amino acids, are most
abundant than arginine and leucine in all five species, achieving 16,4 g per100g crude protein in E. foetida.
methionine, that are limited amino acids in most
feedstuffs, are present in all species of earthworms (Dedeke et al., 2010).
meal (Lumbricus rubellus) has become
one of the natural materials that can be used
as feed additive. The study of Istiqomah et al. (2009) is carried out (1) to evaluate the amino acid
profile of earthworm and earthworm meal, (2) to calculate the value of essential
amino acid index of both materials. It is shown that essential amino acid of
earthworm is dominated by histidine (0,63 % of dry matter basis), meanwhile the
earthworm meal is dominated by isoleucine (1,98 %). The non-essential amino
acid of earthworm and earthworm meal is dominated by glutamic acid (1,52 % and 3,60
% of dry matter basis, respectively). The value of essential amino acid index
obtained from earthworm meal is higher (58,67,%) than those from earthworm (21,23
%). It is concluded that powdering method of earthworm by using formic acid
addition has higher amino acid balance than earthworm.
to data by Istiqomah et
al. (2009) and other authors, earthworm meal of L. rubellus contains 65,63 %
crude protein, earthworm meal of L. terestris contains 32,60 % crude protein, earthworm meal of P. excavatus contains 57,20 % crude protein and have complete amino
acids. Dynes (2003) gives the similar results on crude protein in earthworm
meal of Eisenia andrei and E. foetida.
(E. foetida and L. rubellus) have been ensiled with sorghum and molasses in the
following proportions: 1) 60% earthworms, 40% sorghum; 2) 60% earthworms, 40%
sorghum, adjusting pH to 4,0 with HCl; 3) 60% earthworms, 20% sorghum, 20%
molasses; 4) 60% earthworms, 20% sorghum, 20% molasses, adjusting pH to 4,0
with HCl (Ortega Cerrilla et al., 1996). These four mixtures have been allowed
to ferment for 15 days at 18o C. No essential differences are in the
percentage of moisture, ether extract, crude fiber and crude protein for
treatments 1, 2, 3 and 4, respectively, hence Ortega Cerrilla et al. (1996)
conclude that it is possible to preserve earthworms E. foetida and L. rubellus
by ensiling, adding carbohydrates like sorghum or molasses, and that an addition
of acids to have an adequate fermentation is optional.
vermicomposts contains cow, horse and other manure, agricultural waste, tree leaves
and other vegetable byproducts, processed by earthworms, together with the
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