Agriculture Reference
In-Depth Information
Fish Feeding Trials
The first use of earthworms as a protein source in fish feed was reported by Tacon et al. (1983),
who studied the growth of trout fed on
E. fetida, A. longa,
and
L. terrestris
as a total feed
compared with that of fish fed on a commercial formula. The fish fed frozen
A. longa
and
L.
terrestris
grew as well as or better than fish fed on commercial trout pellets. However, trout did
not grow so well on a whole diet of freeze-dried
E. fetida,
although they grew almost as well
on
E. fetida
blanched in boiling water before freezing. Protein makes up only 15 to 30% of
commercial fish diets, and dried earthworm meal derived from
E. fetida,
even when it had not
been blanched satisfactorily, replaced the fishmeal component of formulated trout pellets at the
normal levels of inclusion between 5 and 30%. Clearly, earthworms have good potential as both
complete feed or protein supplement for trout or other fish. Guerrero (1983) reported that
Tilapia
fish grew better on diets containing earthworm protein supplements from
P. excavatus
than those
provided with other fish meal supplements. Velasquez et al. (1991) reported that earthworm meal
produced from
E. fetida
produced satisfactory growth of rainbow trout with a significant increase
in lipid content.
Chicken Feeding Trials
The first reports of the growth of chickens on a diet with earthworm protein were by Harwood
and Sabine (1978). They found no significant difference in growth of chickens fed on earthworms
and chickens fed on a meat meal protein supplement. Similar results were reported by Taboga
(1980) and Mekada et al. (1979). Jin-you et al. (1982) reported that chickens fed on earthworms
gained weight faster than those given other diets (including fish meal), had more breast muscle,
and consumed less food. Freeze-dried earthworm protein was used by Fisher (1988), and
chickens fed this protein supplement grew well, gained weight per unit of food well, and had
an excellent nitrogen retention when fed diets containing levels of earthworm meal from 72 to
215 g/kg.
Pig Feeding Trials
In feeding trials with both starter and grower pigs (Sabine 1978), young pigs fed an earthworm
protein supplement grew equally well and had similar feed conversion ratios to those grown on
regular commercial protein feeds. Jin-you et al. (1982) also reported that piglets grew better on
diets with earthworm protein supplements than on other protein supplements, weaning was accel-
erated, estrus in sows was earlier, and there was increased disease resistance and a decreased
incidence of white diarrhea. Good growth of young pigs on earthworm protein was also reported
by Edwards and Niederer (1988).
E
CONOMIC
P
OTENTIAL
OF
THE
P
RODUCTION
OF
E
ARTHWORM
P
ROTEIN
FOR
A
NIMAL
F
EED
A detailed study of the economics of production of earthworm protein concluded that the earthworm
meal must be produced at an economic price, although the value of the vermicompost produced
can also be taken into account as complementary income. Earthworms can be produced econom-
ically with relatively low labor inputs. The labor-intensive part of earthworm protein production is
the harvesting process, and this remains the main barrier to successful commercial production of
earthworm protein. More efficient methods of harvesting have been tested and hold considerable
promise for the future.
