Effects of short-timeArtemiaspp. feeding in larvae and different rearing environments in juveniles of common barbel (Barbus barbus) on their growth and survival under intensive controlled conditions

Abstract

The effect of short-time Artemia spp. feeding on growth performance and cumulative survival rate of barbel (Barbus barbus) larvae were studied under controlled aquaria conditions during the 21-day larval period. Three different diets (presenting reduced Artemia feeding) were tested for first exogenous nutrition of larvae (since 13 days post hatch):(1) artificial feed (Asta); (2) Artemia nauplii for 7 days followed by artificial feed; (3) Artemia nauplii for 14 days followed by artificial feed. The longer period of live food statistically improved growth of larvae (W = 174 ± 20 mg and SGR = 14.5 ± 0.5% d −1 ). The artificial dry food Asta without the addition of Artemia nauplii caused statistically decreased growth (W = 135 ± 22 mg and SGR = 13.1 ± 0.7% d −1 ). However, the growth of larvae with the short period of Artemia nauplii (W = 153 ± 25 mg and SGR = 13.8 ± 0.7% d −1 ) did not differ compared to either group. All used feeding diets did not have a significant effect on the cumulative survival rate of larvae ranging from 73 ± 1% to 74 ± 1% at the end of the larval rearing period. The effects of the rearing environment on growth performance and survival rate of juveniles were tested under intensive controlled conditions in aquaria and troughs for 84 days following the larval period (from 34 to 118 dph). The environment of the troughs caused significantly decreased growth (W = 2079 ± 433 mg and SGR = 3.1 ± 0.05% d −1 ) of juveniles compared to ones reared in aquaria (W = 3236 ± 264 mg and SGR = 3.6 ± 0.1% d −1 ) at the end of the juvenile rearing period. Nevertheless, rearing environment did not have a significant influence on the cumulative survival rate of barbels (S C = 90 ± 4% and 81 ± 3% in aquaria and troughs, respectively).

Growth and survival rates, puberty and fecundity in captive common barbel (Barbus barbus L.) under controlled conditions

“…Stripping frequency, egg and sperm production in captive females and males of common barbel (Barbus barbus) during the first reproductive season. Different letters within a column indicate differences in all parameters among the months (phases) of reproductive season (P < 0.05) Our study confirmed the previous observations that live feed is not an essential diet for larvae in common barbel at the start of exogenous feeding (Wolnicki and Górny, 1995;Policar et al, 2007). This fact is caused by relatively advanced ontogenic development of barbel larvae at the beginning of exogenous nutrition compared to larvae of other cyprinids (Peňáz, 1971(Peňáz, , 1973Fiala and Spurný, 2001;Policar et al, 2007;Wolnicki et al, 2009).…”

“…Different letters within a column indicate differences in all parameters among the months (phases) of reproductive season (P < 0.05) Our study confirmed the previous observations that live feed is not an essential diet for larvae in common barbel at the start of exogenous feeding (Wolnicki and Górny, 1995;Policar et al, 2007). This fact is caused by relatively advanced ontogenic development of barbel larvae at the beginning of exogenous nutrition compared to larvae of other cyprinids (Peňáz, 1971(Peňáz, , 1973Fiala and Spurný, 2001;Policar et al, 2007;Wolnicki et al, 2009). Fast growth and high survival rate could be achieved under controlled conditions if the used artificial feed met the nutrient requirements of barbel larvae (Wolnicki and Górny, 1995;Fiala and Spurný, 2001;Policar et al, 2007).…”

“…Artificial stripping of wild barbel broodfish was carried out at the Žleby anglers' club hatchery (Central Bohemia region, 49°54'N and 15°30'E) for the production of larvae according to Policar et al (2007). Fertilized eggs were incubated in three 10 l Zug jars and newly hatched larvae were kept in three Rückl-Vacek incubators (Policar et al, 2004).…”

“…Poncin et al (1987) and Poncin (1989) studied the effects of different photoperiod regimes on the reproduction of barbel under controlled conditions. The optimization of larval and juvenile rearing under controlled conditions was described by Labatzki and Fuhrmann (1992), Wolnicki and Górny (1995), Fiala and Spurný (2001) and Policar et al (2007). However, there is a lack of information about growth and survival rates of barbel juveniles and adults in captivity.…”

Untitled

“…Improperly chosen thermal conditions as well as their fluctuations either delay spawning or cause gametes to mature with defects (Wang et al, 2010;Targońska et al, 2010Targońska et al, , 2012Nowosad et al, 2014a). Final gamete maturation, especially in cyprinids, is induced by hormonal stimulation (Yaron, 1995;Policar et al, 2007; (Kahkesh et al,2010;Targońska et al, 2011b). The bottleneck of this process is the induction of ovulation, whose rate under controlled conditions in barbel is usually about 10% or lower.…”