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The sexual maturity of female snake head fish, Channa striatus was studied by determining fecundity and gonadosomaticindex (GSI). It was found that the size at sexual maturity of female snake head fish was 26.45±3.07 cm (mean ± SD,n=10) in total length and 167.4±48.09 g in body weight. The eggs were floating and rounded. The fertilized eggs had a diameterof 588±20.43 m. The fecundity was 10,279.1±2,527.9 ova/fish and gonadosomatic index (GSI) was 5.07±1.04 %.Newly hatched larvae of snake head fish were produced by induced spawning using chemical injection (Suprefactand Motilium). The sexually mature fishes were cultured in a fiber-glass tank (water volume 300 liters) with the ratio of maleand female brooders 1:1. The fertilization rate, hatching out and hatching rate experiments were carried out using 3 15-literglass aquaria (water volume 10 liters) each containing 1,000 eggs. It was found that the average fertilization rate was 76.50%,hatching out occurred of 28 hr 40 min and average hatching rate was 60.26 % at a water temperature of 26.5-29.0°C. Samplingof the newly-hatched larvae was done at 2-hour intervals, when 20 of them were randomly taken and preserved in 10%buffered formalin for later determination of yolk absorption time. Observation using a microscope revealed that newlyhatched larvae were 3.18±0.11 mm in total length and had yolk sacs of 1,279.71±196.10 m3 in volume. The yolk sacs werecompletely absorbed within 80 hr after hatching at a water temperature of 26.5-29.0°C. Up until full mouth development (startof feeding), 2-hourly samplings of twenty newly hatched larvae were taken from an aquarium for observation of the size ofmouth opening. All the larvae had open mouths about 52 hr after hatching (5.48±0.16 mm TL), and measured 324.30±144.60m in mouth opening.The feeding experiments were carried out using a 15-liter glass aquarium (water volume 10 liters) containing 1,000larvae aged 1.5 days post-hatching (just before the mouth opened). They were fed with Moina at a density of 10 individual/ml. Twenty larvae were collected at random from the aquarium at 2-hourly intervals, preserved in 10 % buffered formalin, andthen dissected to determine the presence of Moina in the digestive tract. The digestive tracts were fixed at 62 hr of hatchingat water temperatures of 28.0-30.5°C, and measured 334.87±149.78 m in mouth opening. The average number of Moina inthe digestive tract at the start of feeding was 0.56 individual/larva.

Feeding scheme experiments were done in a 15-liter glass aquarium (water volume 10 liters) containing 500 of two-dayold larvae (stage at first feeding). It was found that larval snake head fish aged 3-11 days (average total length 6.08-10.86 mm)consumed Moina. Larvae aged 12-15 days (average total length 10.79-14.61 mm) consumed both Moina and commercialpellet (40 % crude protein). Larvae aged more than 16 days consumed only commercial pellet.Determining the daily food uptake by the larvae and juveniles was done in a 15-liter glass aquarium (water volume 10liters) containing 1,000 larvae. The larvae consumed Moina ,provide of a density of Moina 10 individual/ml. The amount offood intake was calculated based on changes of food density in the aquarium with and without fish larvae at 2-hour intervals.It was found that larvae aged 3-15 days consumed Moina. The average uptake of Moina in digestive tract per day of larvaeage 3, 6, 9, 12 and 15 days old was 28.7, 115.70, 162.27, 195.30 and 227.30 individual/larva, respectively at water temperaturesranging between 25 and 28°C.A starvation experiment was carried out using a 15-liter glass aquarium (water volume 10 liters) with three replications.Two hundred newly hatched larvae were kept without feeding. Larvae started to die at 216 hr and totally died within 326 hrafter hatching at water temperature ranging between 28.0 and 30.5°C.

The sexual maturity of female Siamese gourami, Trichogaster pectoralis was studied by determining fecundity and gonadosomatic index (GSI). It was found that the size at sexual maturity of female Siamese gourami was 18.07±1.10 cm (mean±SD) in average total length and 94.20±13.39 g in average body weight. The fecundity was 26,261±5,215.81 ova/fish and gonadosomatic index (GSI) was 10.9±2.1%.Newly hatched larvae of Siamese gourami were produced by induced spawning using chemical injection (Suprefact and Motilium). The sexually mature fishes were cultured in fiber-glass tank (water volume 300 liters) with the ratio of male and female brooders 1:1. The fertilization rate, hatching out and hatching rate experiments were carried out using a 15-liter aquarium (water volume 10 liters) containing 1,000 eggs. It was found that the eggs were floating and rounded. The fertilized eggs had a diameter of 908.25±39.13 μm. The average fertilization rate was 91.12%, hatching out was 22 hr 10 min and average hatching rate was 83.03% at a water temperature of 27.0-30.5ºC. Sampling of the newly-hatched larvae was done at 2-hour intervals, when 20 of them were randomly taken and preserved in 10% buffered formalin for later analysis to determine the time of final yolk absorption. Observation using a microscope revealed that newly hatched larvae were 2.73±0.02 mm in total length and had yolk sacs of 153.76±2.49 μm3 in volume. The yolk sacs were completely absorbed within 110 hr after hatching at a water temperature of 27.0-30.5ºC. Up until full mouth development (start of feeding), 2-hourly samplings of twenty newly hatched larvae were taken from an aquarium for observation of the size of mouth opening. All the larvae had open mouths about 60 hr after hatching (3.56±0.04 mm TL), with the mouths measuring 443.64±24.26 μm in height.The feeding experiments were carried out using a 15-liter glass aquarium (water volume 10 liters) containing 1,000 larvae aged 1.5 days post-hatching (just before the mouth opened). They were fed with rotifer at a density of 10 ind/ml. Twenty larvae were collected at random from the aquarium at 2-hourly intervals, preserved in 10% buffered formalin, and then dissected to determine the presence of rotifer in the digestive tract. The digestive tracts were fixed at 72 hr of hatching at water temperatures of 27.0-30.5ºC, and measured 503.73±22.57 μm in mouth height. The average number of rotifer in the digestive tract at the start of feeding was 0.57 individual/larva.A starvation experiment was carried out using a 15-liter glass aquarium (water volume 10 liters) with three replications. Five hundred newly hatched larvae of Siamese gourami were kept without feeding. Larvae started to die at 72 hr and totally died within 156 hr after hatching at water temperature ranging between 27.0 and 30.5ºC.

The sexual maturity of female climbing perch, Anabas testudineus was studied by determining fecundity and gonadosomatic index (GSI). It was found that the size at sexual maturity of female climbing perch was 15.20±1.24 cm (mean±SD) in total length and 61.10±17.32 g in body weight. The eggs were floating and rounded. The fertilized eggs had a diameter of 830±39 μm. The fecundity was 24,120.5±3,328.24 ova/ fish and gonadosomatic index (GSI) was 10.4±2.5%. Newly hatched larvae of climbing perch were produced by induced spawning using chemical injection (Suprefact and Motilium). The sexually mature fishes were cultured in fiber-glass tank (water volume 300 liters) with the ratio of male and female brooders 2:1. The fertilization rate, hatching out and hatching rate experiments were carried out using a 15-liter glass aquarium (water volume 10 liters) containing 7,000-9,000 eggs. It was found that the eggs were floating and rounded. The fertilized eggs had a diameter of 830±39 μm. The average fertilization rate was 92.67%, hatching out was 20 hr 30 min and average hatching rate was 87.44% at a water temperature of 27.0-30.5ºC. Sampling of the newly-hatched larvae was done at 2-hour intervals, when 20 of them were randomly taken and preserved in 10% buffered formalin for later deter-mination of yolk absorption time. Observation using a microscope revealed that newly hatched larvae were 2.02±0.20 mm in total length and had yolk sacs of 111.33±46.19 mm3 in volume. The yolk sacs were completely absorbed within 92 hr after hatching at a water temperature of 27.0-30.5ºC. Up until full mouth development (start of feeding), 2-hourly samplings of twenty newly hatched larvae were taken from an aquarium for observation of the size of mouth opening. All the larvae had open mouths about 28 hr after hatching (2.95±0.59 mm TL), with the mouths measuring 328.42±32.23 mm in height. The feeding experiments were carried out using a 15-liter glass aquarium (water volume 10 liters) containing 1,000 larvae aged 1 days post-hatching (just before the mouth opened). They were fed with rotifer at a density of 10 ind/ml. Twenty larvae were collected at random from the aquarium at 2-hourly intervals, preserved in 10% buffered formalin, and then dissected to determine the presence of rotifer in the digestive tract. The digestive tracts were fixed at 32 hr of hatching at water temperatures of 27.0-30.5ºC, and measured477.63±47.80 mm in mouth height. The average number of rotifer in the digestive tract at the start of feeding was 1.50 individual/larva. A starvation experiment was carried out using a 15-liter glass aquarium (water volume 10 liters) with three replications. Two hundred newly hatched larvae were kept without feeding. Larvae started to die at 216 hr and totally died within 348 hr after hatching at water temperature ranging between 27.0 and 30.5ºC. The feeding scheme experiments were done in a 15-liter glass aquarium (water volume 10 liters) containing 500 of two-day old larvae (stage at first feeding). It was found that larval climbing perch aged 3- 10 days (average total length 3.02-4.97 mm) consumed rotifer. The larvae of age 8-15 days (average total length 3.94-12.60 mm) consumed Moina. The larvae of age 8-10 days (average total length 3.94-4.97 mm)consumed both rotifer and Moina. The larvae of age 11-day (average total length 5.51 mm) consumed only Moina. The larvae of age 14-15 days (average total length 7.34-12.60 mm) consumed both Moina and artificial feed. Larvae aged more than 16 days consumed only artificial feed. Determining the daily food uptake by the larvae and juveniles was done in a 15-liter glass aquarium (water volume 10 liters) containing 100 larvae. The larvae consumed the living food organism i.e. rotifer or Moina depending on larval stage, with density of rotifer 100 individual/ml or with density of Moina 10 individual/ml. The amount of food intake was calculated based on changes of food density in the aquariumwith and without fish larvae at 2-hour intervals. It was found that the larvae of age 3-6 days (average total length 3.02-3.71 mm) consumed only rotifer. The average uptake of rotifer in digestive tract per day of larvae age 3 and 6 days old were 9 and 16 individual/larva, respectively. The 9-days old larvae (average total length 4.43 mm) consumed both rotifer and Moina, the average uptake of rotifer in digestive tract in a day was 19 individual/larva and that of Moina was 10 individual/larva. The larvae of age 12-15 days (average total length 6.11-12.60 mm) consumed only Moina. The average uptake of Moina in digestive tract per day of larvae age 12 and 15 days old were 98 and 113 individual/larva, respectively.

Natural spawning of sand goby was carried out in earthen ponds and eggs were then collected. Fertilized eggs were incubated in a glass aquaria for hatching. The feed and feeding scheme experiments were done in the 500 liters (water volume 300 liters) rearing tanks containing 1,000-1,500 of two-day old larvae (stage at first feeding). It was found that the larvae 3-18 days old (average total length 0.31-0.41 cm) preferably fed only on rotifer while the 21-27 day-old larvae (average total length 0.44-0.65 cm) fed on rotifer and Artemia, and the 30-45 day- old larvae (average total length 0.69-2.15 cm) fed only on Moina.

Time of digestion experiments were carried out in a 15-liter rearing glass aquaria (water volume 10 liters) containing 1,500 larvae. The larvae were fed with sufficient rotifer, Artemia or Moina and then transferred to another rearing glass aquarium without food. Samples of 20 larvae were checked at 10-minute intervals until no food remained in the larval digestive tract. It was found that the time required to empty the larval digestive tract with rotifer, Artemia or Moina was as follows. Larvae 3-18 days old fed with rotifertook 130-180 minutes to empty the digestive tract while larvae 21-27 days old fed with rotifer and Artemia took 110-120 minutes and larvae 30-45 days old fed with Moina took 80-100 minutes at water temperature of 25-29ºC. Time consumed to empty the gut content tended to decrease as larval age increased. Experiments to determined the time and amount of prey required to get satiation were carried out in a 15-liter rearing glass aquaria (water volume 10 liters) containing 1,500 larvae. The larvae were fed with rotifer, Artemia or Moina after starvation of 24 hr. Samples of 20 larvae were checked at 10- inutes intervals after the start of feeding until 3 hr. It was found the time required to fill the larval digestive tract with rotifer, Artemia or Moina for 3-18 days old larvae was 80-110 minutes and amount of rotifer to get satiation was 4.8- 26 ind/larvae. For 21-27 day-old larvae the corresponding time was 60-80 minutes and was 28.5-31.6 ind/ larvae. For 30-45 day-old larvae the time was 40-60 minutes and amount of Moina to get satiation was 34.6- 52.4 ind/larvae at water temperature of 25-29ºC. The time required to fill the larval gut, tends to decrease with larval age but the amount of prey required to fill the larval gut, tends to increase with larval age. Experiments to determined the amount of food uptake in a day were done in a 15-liter rearing glass aquaria (water volume 10 liters) containing 500 larvae, and 10 ind/ml of rotifer, Artemia or Moina. The amount of food taken was calculated based on changes of rotifer, Artemia or Moina density in the rearing glass aquarium with and without fish larvae, the 5 samples of each replication were examined at 2 hourly intervals. The average amounts of rotifer uptake in a day for 3, 6, 9, 12, 15 and 18 day-old larvae were 58.8, 95.4, 64.0, 88.8, 134.0 and 147.4 ind/larvae, respectively. The mean numbers of rotifer added Artemia uptake in a day by 21, 24 and 27-day old larvae were 181.6, 185.6 and 241 ind/larvae, respectively. And average amounts of Moina uptake in a day for 30, 33, 36, 39, 42 and 45 day-old larvae were 177.4, 179.4, 214.8, 249.6, 362.8 and 366.2 ind/larvae, respectively.