explained by an increase in the nutritive phagocytes, a non-gametic component of
gonads (Pérez et al. 2010). A similar spawning period was reported for L. albus
populations of the Magellanic region (Bay-Schmith et al. 1981; Arana et al. 1996;
Oyarzún et al. 1999). However, populations of L. albus from other sites do not
seem to follow this pattern. In the Malvinas Islands, L. albus spawns during the
warmest time of the year (summer). This allows for greater growth of their pelagic
larvae and newly settled juveniles (Schuhbauer et al. 2010). Spawning is delayed
along the Chilean coast as latitude increases (Zamora and Stotz 1992; Vásquez
2007).
In the BC population of Loxechinus albus, the reproductive cycle may be
influenced by photoperiod fluctuation and primary production. In contrast, water
temperature was not correlated with gonadal maturation (Pérez 2009; Pérez et al.
2010). Pérez et al. (2008, 2010) made the first attempt to analyze the energetic
content of different organs of L. albus using calorimetric determinations. High
values of gonad energy content suggest the presence of lipids in the gonads. Both
gonad energy content and total gonad energy content were higher in females than
in males. The reproductive output of L. albus was higher in females than males,
thus indicating that spawning is energetically more expensive in females (Pérez
et al. 2010). The values of gonad energy content and total gonad energy content
showed minimum values in winter (ripe stage) and maximum values in spring
(spawned stage) (Pérez et al. 2008). Total gonad energy content reached higher
monthly average values (50–200 kJ) than total gut energetic content (20–40 kJ).
These authors suggested this difference indicates that the gonads constitute the
most important storage organs in L. albus. Organic stores are built up in the gonads
after spawning and then used in gamete production.
The gonads of this sea urchin are a highly valued seafood product and are
considered as delicacies in many parts of the world. Pérez et al. (2010) suggested
that autumn is the best period to harvest this species since the gonads are in early
stages, having the quality (color, texture, and flavor) desired by the market.
Malanga et al. (2007) studied the addition of carotenoid in diet in order to improve
the organoleptic properties and protection against oxidative damage of gonads.
They fed L. albus with carotenoid during the pre-reproductive period and during
spawning. b-carotenoids, not only provided a desirable color to the product, but
also protect their lipid constituents against oxidation. The influence of seasonal
factors on oxidative metabolism in the L. albus gonads was tested by Malanga
et al. (2009). They found that lipid radical content showed non-significant changes
with seasons while the content of ascorbyl radicals and -tocopherol were lower in
spring and summer as compared to winter. The authors suggested the existence of
different profiles of response against oxidative stress of the lipophilic and hydrophilic milieus in L. albus gonads.
The sand dollar Encope emarginata inhabits the Atlantic Ocean from Colombia
to the northern coasts of Argentina. Brogger and Penchaszadeh (2003) described
some aspects of population ecology at MDP at 15–25 m depth. Length frequency
analysis indicated that E. emarginata is characterized by slow growth rates,
378
M. I. Brogger et al.
gonads (Pérez et al. 2010). A similar spawning period was reported for L. albus
populations of the Magellanic region (Bay-Schmith et al. 1981; Arana et al. 1996;
Oyarzún et al. 1999). However, populations of L. albus from other sites do not
seem to follow this pattern. In the Malvinas Islands, L. albus spawns during the
warmest time of the year (summer). This allows for greater growth of their pelagic
larvae and newly settled juveniles (Schuhbauer et al. 2010). Spawning is delayed
along the Chilean coast as latitude increases (Zamora and Stotz 1992; Vásquez
2007).
In the BC population of Loxechinus albus, the reproductive cycle may be
influenced by photoperiod fluctuation and primary production. In contrast, water
temperature was not correlated with gonadal maturation (Pérez 2009; Pérez et al.
2010). Pérez et al. (2008, 2010) made the first attempt to analyze the energetic
content of different organs of L. albus using calorimetric determinations. High
values of gonad energy content suggest the presence of lipids in the gonads. Both
gonad energy content and total gonad energy content were higher in females than
in males. The reproductive output of L. albus was higher in females than males,
thus indicating that spawning is energetically more expensive in females (Pérez
et al. 2010). The values of gonad energy content and total gonad energy content
showed minimum values in winter (ripe stage) and maximum values in spring
(spawned stage) (Pérez et al. 2008). Total gonad energy content reached higher
monthly average values (50–200 kJ) than total gut energetic content (20–40 kJ).
These authors suggested this difference indicates that the gonads constitute the
most important storage organs in L. albus. Organic stores are built up in the gonads
after spawning and then used in gamete production.
The gonads of this sea urchin are a highly valued seafood product and are
considered as delicacies in many parts of the world. Pérez et al. (2010) suggested
that autumn is the best period to harvest this species since the gonads are in early
stages, having the quality (color, texture, and flavor) desired by the market.
Malanga et al. (2007) studied the addition of carotenoid in diet in order to improve
the organoleptic properties and protection against oxidative damage of gonads.
They fed L. albus with carotenoid during the pre-reproductive period and during
spawning. b-carotenoids, not only provided a desirable color to the product, but
also protect their lipid constituents against oxidation. The influence of seasonal
factors on oxidative metabolism in the L. albus gonads was tested by Malanga
et al. (2009). They found that lipid radical content showed non-significant changes
with seasons while the content of ascorbyl radicals and -tocopherol were lower in
spring and summer as compared to winter. The authors suggested the existence of
different profiles of response against oxidative stress of the lipophilic and hydrophilic milieus in L. albus gonads.
The sand dollar Encope emarginata inhabits the Atlantic Ocean from Colombia
to the northern coasts of Argentina. Brogger and Penchaszadeh (2003) described
some aspects of population ecology at MDP at 15–25 m depth. Length frequency
analysis indicated that E. emarginata is characterized by slow growth rates,
378
M. I. Brogger et al.