Effect of periphyton on growth performance of grey mullet, Mugil cephalus (Linn.), in inland saline groundwater ponds

Abstract

The present study attempts to assess the potential of artificial substrates to enhance fish production in inland saline groundwater ponds through periphyton production. Grey mullet, Mugil cephalus, was cultured for 100 days in ponds with substrate (treatment ponds) and without substrate (control ponds). To enhance the surface area, bamboo poles were used as substrate. The periphyton population, pigment concentration and hydrobiological characteristics of pond water were monitored. The studies revealed little difference in most of the water quality parameters observed in the two treatments. However, turbidity (27.0 ± 0.1-35.0 ± 0.1 Nephalo Turbidity Unit (NTU)), chlorophyll ÔaÕ (6.6 ± 0.6-7.6 ± 0.6 lg L )1 ), plankton population (phytoplankton 8.4 · 10 3 -9.4 ·10 3 numbers L )1 ; zooplankton 4.0 · 10 3 -5.1 · 10 3 numbers L )1 ) and NH 4 -N (2.0 ± 0.2-2.3 ± 0.1 mg L )1 ) were high in the treatment with no additional substrate; however, in the treatment with substrate the total Kjeldahl nitrogen (9.8 ± 0.8-10.8 ± 0.7 mg L )1 ) and o-PO 4 (0.1 ± 0.01-0.1 mg L )1 ) remained significantly (P < 0.05) higher. Highest periphyton biomass in terms of dry matter (DM) (0.8 ± 0.01-1.4 ± 0.01 mg cm )2 ), ash free DM (0.4 ± 0.0-0.6 ± 0.01 mg cm )2 ), chlorophyll ÔaÕ (3.1 ± 0.2-8.1 ± 0.8 lg cm )2 ) and pheophytin ÔaÕ (1.9 ± 0.4-3.9 ± 0.5 lg cm )2 ) was observed at 50 cm depth in ponds provided with additional substrate. Fifteen plankton genera showing periphytic affinity colonized the bamboo substrates. Fish growth (mean fish weight 524.3 ± 8.7 g and SGR 2.5 ± 0.1) was significantly (P < 0.05) higher in ponds provided with additional substrate compared with control ponds (387.2 ± 6.0). Length-weight relationship (LWR) (W ¼ cL n ) also showed that the exponential value (ÔnÕ) of length was high in substrate-supported ponds (n ¼ 2.36) in comparison with controls (n ¼ 1.09). These studies suggest that a periphyton-supported aquaculture system can be used successfully for the culture of herbivorous brackishwater fish species like M. cephalus in inland saline groundwaters and thus could contribute to the development of sound and sustainable aquaculture technology.

Effect of inland water salinity on growth performance and nutritional physiology in growing milkfish, Chanos chanos (Forsskal): field and laboratory studies

“…For chlorophyll a , a known amount of water was filtered through Whatman filter paper (no. 40) and determined (see Jana et al., 2004 for details) following Boyd (1990).…”

Evaluation of indigenous marine periphyticAmphora,NaviculaandCymbellagrown on substrate as feed supplement inPenaeus monodonpostlarval hatchery system

“…Most of the information is on fresh water system showing that the various substrates contribute to growth and production of the different cultured species (Wahab et al 1999; Thompson et al 2000; Tidwell et al 2000; Azim et al 2001; Keshavanath et al 2001). Reports by Jana et al . (2004, 2006) have shown that colonization of periphyton on bamboo poles increase the growth rate of brackishwater finfish Mugil cephalus (35%) and Chanos chanos (73%) cultured in saline groundwater ponds.…”

Feeding Ecology and Prey Preference of Grey Mullet, Mugil cephalus (Linnaeus, 1758) in Extensive Brackish Water Farming System

“…This species is widely cultured in both brackish and freshwater semi-intensive fishponds [23] and can utilize both supplemental feed and/or natural food [24]. Studies on food and feeding habit of stripped grey mullet worldwide indicates that the food spectrum is mainly constituted with Diatoms, green and blue green algae, Dinoflagellates, Protozoa, macro plant detritus, Copepods, Nematodes and Foraminifera according to the order of dominance [25][26][27][28][29][30][31].…”