190
After a series of zoo-technology optimizations for this life stage, Sykes et al.
(2013a) managed to rear cuttlefish throughout the hatchling stage performing an early
weaning on the first day after hatching with some success (Fig. 11.4d on the right—
cuttlefish hatchlings eating frozen grass shrimp). These results are encouraging but
further research regarding this issue in terms of nutrition, digestion, etc. is needed.
For the time being, the use of live grass shrimp of appropriate size is still recommended during the hatchling stage and the weaning to frozen grass shrimp should
be performed after 20–30 DAH depending on the temperature.
11.5.3 Growth and Survival
Information regarding cuttlefish hatchlings’ behaviour, growth and morphological changes during this stage was reported by Nixon and Mangold (1998). Growth
rates vary directly with temperature, inversely with size, and play a major role in
determining the species’ life span (Domingues et al. 2006). Maintaining animals
of different age groups together should be avoided at any stage but especially at
this stage. It is acceptable, for rearing purposes, to join hatchlings with an age difference of up to 10 DAH. Joining animals with larger age differences will generate increased competition for food, promote the establishment of food hierarchies
and, therefore, increase mortality. This stage of cuttlefish life is characterized by
the highest growth rates but, at the same time, where mortalities may be higher.
Table 11.3 resumes the hatchlings growth rates, mortality, feeding rates and food
conversions (during the first 30 days of life, according to type of tank and food)
published since 1999.
Normal growth, development and survival depend on the egg content (this content reflects food given to females and the same female may lay eggs with different
amounts of yolk depending on the number of spawns and age), food quality, the
best quality of seawater and tank setup conditions. Food consumption and feeding
rates during this life stage are also extremely high, when compared with the values
registered in the subsequent stages.
11.6 Ongrowing of Juveniles and Adults
11.6.1 Tank and Earthen Pond Conditions
Despite the first attempts of rearing cuttlefish in earthen ponds which were performed by obtaining eggs in the wild with egg collectors and placed in these ponds
and collecting the juveniles 3 months later (Palmegiano and Sequi 1981), this type
of procedure is considered extensive culture. This was, and still is, performed in
countries such as Italy, Portugal (Coelho et al. 1989; Gonçalves 1989) and Tunisia
(Rodger and Davies 2000). Nevertheless, some authors believe that the potential of
cuttlefish culture is able to sustain semi-intensive or intensive aquaculture.
A. V. Sykes et al.
After a series of zoo-technology optimizations for this life stage, Sykes et al.
(2013a) managed to rear cuttlefish throughout the hatchling stage performing an early
weaning on the first day after hatching with some success (Fig. 11.4d on the right—
cuttlefish hatchlings eating frozen grass shrimp). These results are encouraging but
further research regarding this issue in terms of nutrition, digestion, etc. is needed.
For the time being, the use of live grass shrimp of appropriate size is still recommended during the hatchling stage and the weaning to frozen grass shrimp should
be performed after 20–30 DAH depending on the temperature.
11.5.3 Growth and Survival
Information regarding cuttlefish hatchlings’ behaviour, growth and morphological changes during this stage was reported by Nixon and Mangold (1998). Growth
rates vary directly with temperature, inversely with size, and play a major role in
determining the species’ life span (Domingues et al. 2006). Maintaining animals
of different age groups together should be avoided at any stage but especially at
this stage. It is acceptable, for rearing purposes, to join hatchlings with an age difference of up to 10 DAH. Joining animals with larger age differences will generate increased competition for food, promote the establishment of food hierarchies
and, therefore, increase mortality. This stage of cuttlefish life is characterized by
the highest growth rates but, at the same time, where mortalities may be higher.
Table 11.3 resumes the hatchlings growth rates, mortality, feeding rates and food
conversions (during the first 30 days of life, according to type of tank and food)
published since 1999.
Normal growth, development and survival depend on the egg content (this content reflects food given to females and the same female may lay eggs with different
amounts of yolk depending on the number of spawns and age), food quality, the
best quality of seawater and tank setup conditions. Food consumption and feeding
rates during this life stage are also extremely high, when compared with the values
registered in the subsequent stages.
11.6 Ongrowing of Juveniles and Adults
11.6.1 Tank and Earthen Pond Conditions
Despite the first attempts of rearing cuttlefish in earthen ponds which were performed by obtaining eggs in the wild with egg collectors and placed in these ponds
and collecting the juveniles 3 months later (Palmegiano and Sequi 1981), this type
of procedure is considered extensive culture. This was, and still is, performed in
countries such as Italy, Portugal (Coelho et al. 1989; Gonçalves 1989) and Tunisia
(Rodger and Davies 2000). Nevertheless, some authors believe that the potential of
cuttlefish culture is able to sustain semi-intensive or intensive aquaculture.
A. V. Sykes et al.