environment to Eisenia fetida. The essential factor that contributes to attain maximum growth of organism is nutrition. Nutrition resources for earthworms are organic
material, live bacteria, algae, fungi, nematodes, and protozoa (Sarojini et al. 2009).
Growth rate provides a comparative analysis, and it is an indicator of growth of
earthworm in different feed mixtures (Vodounnou et al. 2016).
The maximum growth rate in cow dung treatment indicates that it could supply
sufficient nutrients for the earthworms. The decrement in growth rate in the later
phase of the experiment in earthworm may be due to the exhaustion of feed mixture,
but they also stated that vegetable and food mixed with buffalo dung could be a good
feedstock for vermicomposting of organic wastes (Sangwan et al. 2008). Suthar
(2008b) reported that the growth of the earthworms depends on microbial communities and nutrient availability in feed mixture. The stocking density of earthworms
may affect the growth patterns during vermicomposting (Suthar 2011). Various
pollutants may also affect the growth of earthworms, and it can be altered by direct
toxic effects on the physiology of earthworms or by variations in the energy budget
to prevent such toxic effects (Spurgeon and Hopkin 1996). The energy required for
combating the poisonous effects ultimately results in the reduction in energy
required for growth and development (Donker et al. 1993). Vodounnou et al.
(2016) reported that the variation in growth performance in different feed mixtures
may be due to the quality of feedstock and the percentage of mixing substrate. The
higher amount of crop residue in feed mixture also affects the growth and reproduction due to variation in nutrient content and palatability or may be due to some
growth retarding substances (Suthar 2008a).
Cocoon is small, translucent, spherical capsule in which earthworms lay their
eggs (Bhat et al. 2016b). There was lesser number of cocoons due to
P. hysterophorus treatment. The onset as well as rate of cocoon formation depends
on quality of feed mixtures (Bhat et al. 2015) as food source plays a significant role
in cocoon formation. Rate of cocoon production depends on the biochemical differences between the feed qualities, which plays an important role in determining the
time to reach sexual maturity (Edwards et al. 1998). During vermicomposting
process, shortage of food and conversion of whole food into vermicompost are
major factors responsible for low cocoon production (Suthar 2012). The variations
in cocoon production of worms in different waste mixtures are related to the quality
and palatability of food source (Bhat et al. 2017b). The feed which has sufficient
amount of organic matter and nonassimilated carbohydrates promotes better growth
and reproduction in earthworms (Edwards 1988). Suthar (2006) suggested that
during vermicomposting, decomposition activities and microbial biomass are also
important in determining the biomass of earthworm and cocoon production.
The hatchability was reduced by P. hysterophorus treatment. It can be correlated
with the low number of cocoons production. During vermicomposting process, the
hatchability directly depends on the rate of cocoon formation (Singh et al. 2016).
Number of hatchlings may also be considered as an indicator of evaluating the effect
of heavy metals on earthworms (Bhat et al. 2016a). Reinecke and Reinecke (1997)
reported that the exposure to heavy metals leads to the ultrastructural damage in the
sperms of earthworms, which resulted in the lower fertility and viability of cocoons.
15 Waste Management Practices and Their Impact on Earthworms
255
material, live bacteria, algae, fungi, nematodes, and protozoa (Sarojini et al. 2009).
Growth rate provides a comparative analysis, and it is an indicator of growth of
earthworm in different feed mixtures (Vodounnou et al. 2016).
The maximum growth rate in cow dung treatment indicates that it could supply
sufficient nutrients for the earthworms. The decrement in growth rate in the later
phase of the experiment in earthworm may be due to the exhaustion of feed mixture,
but they also stated that vegetable and food mixed with buffalo dung could be a good
feedstock for vermicomposting of organic wastes (Sangwan et al. 2008). Suthar
(2008b) reported that the growth of the earthworms depends on microbial communities and nutrient availability in feed mixture. The stocking density of earthworms
may affect the growth patterns during vermicomposting (Suthar 2011). Various
pollutants may also affect the growth of earthworms, and it can be altered by direct
toxic effects on the physiology of earthworms or by variations in the energy budget
to prevent such toxic effects (Spurgeon and Hopkin 1996). The energy required for
combating the poisonous effects ultimately results in the reduction in energy
required for growth and development (Donker et al. 1993). Vodounnou et al.
(2016) reported that the variation in growth performance in different feed mixtures
may be due to the quality of feedstock and the percentage of mixing substrate. The
higher amount of crop residue in feed mixture also affects the growth and reproduction due to variation in nutrient content and palatability or may be due to some
growth retarding substances (Suthar 2008a).
Cocoon is small, translucent, spherical capsule in which earthworms lay their
eggs (Bhat et al. 2016b). There was lesser number of cocoons due to
P. hysterophorus treatment. The onset as well as rate of cocoon formation depends
on quality of feed mixtures (Bhat et al. 2015) as food source plays a significant role
in cocoon formation. Rate of cocoon production depends on the biochemical differences between the feed qualities, which plays an important role in determining the
time to reach sexual maturity (Edwards et al. 1998). During vermicomposting
process, shortage of food and conversion of whole food into vermicompost are
major factors responsible for low cocoon production (Suthar 2012). The variations
in cocoon production of worms in different waste mixtures are related to the quality
and palatability of food source (Bhat et al. 2017b). The feed which has sufficient
amount of organic matter and nonassimilated carbohydrates promotes better growth
and reproduction in earthworms (Edwards 1988). Suthar (2006) suggested that
during vermicomposting, decomposition activities and microbial biomass are also
important in determining the biomass of earthworm and cocoon production.
The hatchability was reduced by P. hysterophorus treatment. It can be correlated
with the low number of cocoons production. During vermicomposting process, the
hatchability directly depends on the rate of cocoon formation (Singh et al. 2016).
Number of hatchlings may also be considered as an indicator of evaluating the effect
of heavy metals on earthworms (Bhat et al. 2016a). Reinecke and Reinecke (1997)
reported that the exposure to heavy metals leads to the ultrastructural damage in the
sperms of earthworms, which resulted in the lower fertility and viability of cocoons.
15 Waste Management Practices and Their Impact on Earthworms
255