Omidvar Farhadian
Abstract
In this research, gut contents of white leg shrimp Litopenaeus vannamei were investigated for 113 days culture period at earthen ponds in Delvar of Bushehr, by sampling every 15 days. Results showed that artificial food had highest weight percentage in gut contents (foregut, midgut, and hindgut) following ...
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In this research, gut contents of white leg shrimp Litopenaeus vannamei were investigated for 113 days culture period at earthen ponds in Delvar of Bushehr, by sampling every 15 days. Results showed that artificial food had highest weight percentage in gut contents (foregut, midgut, and hindgut) following in order by detritus, zooplankton, phytoplankton, and macro-benthic. In the beginning of culture period, macro-bentic were observed in larval gut contents while other food items were throughout culture period. The maximum occurrence of detritus in gut contents was at 26 and 40 days-old larvae while highest phytoplankton was obtained at 86-days-old larvae in end of culture period. The zooplankton had approximately similar amounts throughout culture period in different parts of gut, while macro-benthic only observed at 26-old-days larvae with maximum amount at foregut and midgut. The mean highest gut fullness attained at foregut (0.95 %) and lowest at hindgut (0.20 %). The dominant color of gut content was green-brown in all parts of gut that could be due to consumption of natural pond products. This study illustrated that most consumed food items in L. vannamei was prepared by natural pond foods. In addition, detritus and plankton have most important in L. vannamei during culture period.
Mohammad Hossein Khanjani; Omidvar Farhadian; Yazdan Keivany; Eisa Ebrahimi
Volume 12, Issue 1 , April 2013, , Pages 67-76
Abstract
The most important factors controlling cladocerans production, growth, and morphometric characters are temperature, food quantity and quality and photoperiod. Effects of temperature and photoperiod on production, and morphometric characters of cladoceran, Ceriodaphnia quadrangular, were examined by culturing ...
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The most important factors controlling cladocerans production, growth, and morphometric characters are temperature, food quantity and quality and photoperiod. Effects of temperature and photoperiod on production, and morphometric characters of cladoceran, Ceriodaphnia quadrangular, were examined by culturing on green algae Scenedesmus quadricauda in 250 ml conical flasks (150 ml water). Treatments used for temperature (˚C)and photoperiod (light hours:dark hours) were 20,25,30 (˚C) and 12:12,24:0 and 0:24, respectively. The maximum population density (5.51 ind./ml) obtained at 24:0 and 30 (˚C), while maximum body length (731 µm) and maximum body width (491 µm) obtained at 0:24 and 20 (˚C). Correspondingly, the maximum adult (61 %), maximum neonate (39 %) and young (9 %) in population under culture conditions of 0:24, 12:12,24:0 (L: D) and 20 (˚C) obtained, respectively. Overall, this research showed that growth and reproduction of Ceriodaphniaquadrangula gave better performance at 25 (˚C)and 24:0, light: dark photoperiod.
Omidvar Farhadian; Delaram Taghavi; Azar Moradipour; Roya Sedaghat
Volume 11, Issue 4 , March 2013, , Pages 64-73
Abstract
Artemia nauplii, despite their marine origin, have a good potential for application in the freshwater ornamental fish culture. In this study, two types of Artemia urmiana and Artemia franciscana were used for feeding of Guppy (Poecilia reticulata Peters) Larvae. Newly hatched fresh nauplii at three different ...
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Artemia nauplii, despite their marine origin, have a good potential for application in the freshwater ornamental fish culture. In this study, two types of Artemia urmiana and Artemia franciscana were used for feeding of Guppy (Poecilia reticulata Peters) Larvae. Newly hatched fresh nauplii at three different densities of 3, 6, and 12 ind./ml as live feeds were compared for measuring larval ingestion rate. Results showed that type and density of Artemia nauplii had significant effects on ingestion rate (P<0.05). The average ingestion rate in larvae which maintain 12 hours starvation (first set of experiment) were 36, 244, and 664 ind./larvae/day for A. urmiana, correspondingly, for A. franciscana were 160, 480, and 880 ind./larvae/day at densities of 3, 6, and 12 ind./ml, respectively. The average ingestion rate of guppy larvae with 24, 48 and 72 hours feeding preconditions (2nd, 3rd and 4th set of experiment) were significantly (P<0.05) decreased. After starvation, the ingestion rate of guppy larvae fed A. urmiana had range 22-54, 86-102, and 148-188 ind./larvae/day, correspondingly, for A. franciscana 66-100, 100-260, and 200-224 ind./larvae/day at 3, 6, and 12 ind./ml, respectively. The use of suitable densities of 6 and 12 ind./ml from Artemia nauplii could increase efficiency of utilization and also improve Guppy larvae production.
Omidvar Farhadian; Mohammad Hossein Khanjani
Volume 10, Issue 3 , September 2012, , Pages 48-56
Abstract
Temperature and photoperiod are important parameters in zooplankton culture, particularly in cladoceran culture due to their significant effect on growth and reproduction. Effects of temperature and photoperiod on the growth and fecundity of a cladoceran, Moina macrocopa was examined by culturing and ...
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Temperature and photoperiod are important parameters in zooplankton culture, particularly in cladoceran culture due to their significant effect on growth and reproduction. Effects of temperature and photoperiod on the growth and fecundity of a cladoceran, Moina macrocopa was examined by culturing and feeding it with green algae Scenedesmus quadricauda in 500 ml conical flasks. Treatments used for temperature (0C)and photoperiod were 25, 30, 35 (0C) and 12:12, 24:0 and 0:24(light:dark hours), respectively. The maximum population density (310.5 individuals/flask), maximum specific growth rate (SGR) (0.387 individuals /day), shortest population doubling time (Dt) (1.79days) and highest fecundity (8.5 offsprings/ female) obtained at 30(0C). Correspondingly, the maximum population density (320.7 ind/flask), maximum SGR (0.538 ind/day), shortest Dt (1.28 days) and highest fecundity (7.54 offsprings/ female) determined at 24:0 light:dark photoperiod. Overall, this research showed that growth and reproduction of M. macrocopa at 30 (0C) and 24:0 light:dark photoperiod gave significant performance (P<0.05) compared to other examined treatments. Mass culture of this species under the mentioned conditions of temperature and photoperiod could provide suitable live food for use in fish larvaiculture.