Feeding regime of comb-jelly, Mnemiopsis leidyi, in the Caspian sea was investigated by analysing the stomach contents of about a thousand specimens collected from cities of Fereidoun-kenar, Noushahr and Noor during spring, summer and autumn. The study of feed particles in the stomachs of the juvenile and adult specimens from all the sampling stations at all seasons revealed the presence of mainly Calanoida and Acartia. Copepods and fish seeds followed next in volume; vegetal particles constituted the least volume. Over 80% of the stomachs of the sampled specimens was found to be full indicating that comb-jelly is voracious.

The gut contents of 73 rainbow trout samples from Khoramnaz river and 32 samples from Beshar river were analyzed to determine the feeding regime. Maximum and minimum length of fish was 46 and 16cm. The highest percent of food items in trout collected from Khoramnaz River belonged to nymph of Plecoptera (41%), Amphipods (15.38%), larvae of Hydropsyche (Trichoptera) (11.11%), larvae of Diptera (9%), and nymph of Ephemeroptera (5%), and in Beshar river belonged to small fishes (Capoeta sp.) (38.88%), larvae of Hydropsyche (Trichoptera) (22.22%), nymph of Ephemeroptera (13.22%), adult insects (11%), crab (9%) and larvae of Tipula (Diptera) (2.84%). Benthos diversity of Khoramnaz river was higher than that of Beshar river. There was a positive correlation between the food items in fish guts and the food items in Beshar river (P<0.01, R2=0.98) and in Khoramnaz river (P<0.01, R2=0.86).

Study of dietetic diet of Psettodes erumei dandelion on the coast of Sistan province In the Oman Sea, 173 samples were taken at the time before Manson and after Manson in 2011 In this regard, nutritional factors like Determination of food priority index, empty stomach filling and relative length of the intestine were investigated. The gastric emptying index (CV) was found in all the examined samples This fish is a medium with moderate nutrition. It was also determined by the time of the analysis of this index that This fish is a species with moderate nutrition. It was also determined by the time of this index This species has a moderate nutrition before and after the manson. The Indicator Length Index (RLG) for this species indicates that the spittoon fish is a part of the carnivorous fish, and its diet includes: fish, shrimp Crab, Scalo, Marine Tetaya, Fish eggs, Worm, etc. Fat preferences were obtained for 88% of fish, 8% for crustaceans, 2% for shellfish and 2% for other fish. Fish, therefore, was recognized as the main source of dental plaque. Investigating the relationship between length and weight showed that the growth of this fish with allometric growth factor (26. 23 b) was. Also, the male sex ratio was 1. 22: 0. 78.

The current study was conducted to evaluate effects of sequential or wet feeding programs subsequent to and early meal feeding regime on performance, carcass characteristics and humoral immunity in broiler chicks. 192 Ross 308 chicks (seven-day old) were allocated to four treatments at four replicates (12 chicks per plot) based on a Completely Randomized Design. Treatments were included: control group (C) where birds had free access to feed throughout the experiment, meal fed groups (MF) where birds were meal fed from 7 to 14 d and subsequently meal fed by the control diet (MFC), meal fed a wet diet (MFW) or subjected to a sequential feeding program (MFS) until day 42. The results showed a statistical reduction of feed intake and increased feed conversion ratio during the meal feeding period (P<0.05). Consequently, meal fed chicks had a depressed body weight at 14 d, which was later, compensated (P<0.05). Following meal feeding, birds in the meal fed a wet diet (MFW) group exhibited the highest body weight, but the sequential fed group had significantly (P<0.05) lower feed intake, body weight and feed conversion ratio (FCR) compared to the other groups. The highest relative weight of small intestine and the lowest abdominal fat pad percentage were observed in the MFS group (P<0.05). Birds' antibody responses to Newcastle, Influenza viruses and sheep red blood cell were not influenced by feeding regimes. It is concluded that feeding a wet diet following meal feeding programs can be effectively used in broiler chicken production.

In this study, granulated sludge synthesized in a sequence batch reactor (SBR) and then granulated sludge was transferred to continuous feeding and intermittent discharge (CFID) bioreactor. Two independent variables (air flow rate and hydraulic retention time (HRT)) were considered to optimize the process. Subsequently, long term performance (150 days) of the bioreactor was assessed by monitoring nine responses. The process optimization in CFID regime was performed using a central composite facecentered design (CCFD) and analyzed using response surface methodology (RSM). Based on obtained data, the optimum conditions were achieved at HRT of 7-8 h and air flow rate of 2-3. 5 L/min. The CFID with granular sludge acted as a high rate bioreactor as the granular sludge could provide high MLSS concentrations (around 10000 mg/L) in a bioreactor.

This research was carried out with the aim of determining the food indicators and dominant baits of Kutum, Rutilus friss fingerling in the form of a project to investigate the biological condition of Kutum fry released in the Tajen river estuary in 2022. Sampling was carried out using a beach seine net with a mesh size of 5 mm and a length of 70 m. The average length and weight of the fish caught were 2.5 cm and 1.25 grams, respectively. The identified food items included phytoplankton, zooplankton and zoobenthos groups. The Gastrosomatic index (GaSI) showed that on average it was 45.8±20.3, the minimum and maximum of which were 2.3 and 104.1, respectively and showed a significant difference (p<0.05). The condition factor (K) of R. frisii fingerling showed that its value varied from 0.12 to 3.3 and on average it was 0.9±0.53 and had a significant difference (p<0.05. The Vacuity index (VI) showed that the R. frisii fingerling in this stage of life have constant activity and did not have empty intestines.The study of the Important Species Index (ISI) in the digestive system of R. frisii fingerling showed that the Bacillariophyta was recognized as the most important food in the intestinal contents with 43%. The cluster analysis of consumed food baits based on Pearson's coefficient of homogeneity showed that Bacillariophyta and Cyanophyta the most similar was found (0.824). The frequency of occurrence index (FI) showed that the Bacillariophyta, Cyanophyta Rotifera and Arthropoda as a main food, and the Eaglenaphyta and Chlorophyta the secondary food and Cilliophora and zoobenthos rare food items was found.

The aim of the research was to determine the effect of feeding frequency on growth indicators, carcass composition, activity of some digestive enzymes and survival of beluga (Huso huso) larvae. For this purpose, the total number of 10800 beluga larvae, with initial weight of 0.048+0.001 g, were randomly stocked in 36 500-liter fiberglass tanks containing 100 liters of well water, for 31 days with a feeding frequency of 6 and 12 times a day using Artemia nauplii, Artemia biomass, Daphnia, chironomid larvae and formulated diet were reared. The results showed that, feeding larvae with chironomid larvae or Artemia biomass, could increase the survival rate and weight of larvae, respectively. The survival percentage of the treatments on different days after hatching of the larvae during 12 times of feeding per day in most treatments was significantly higher than that of 6 times of feeding per day (p<0.05). The average weight of larvae in different treatments, when feeding 12 times a day compared to feeding 6 times a day, had no statistically significant difference (p>0.05). In most treatments, carcass protein content of larvae, during 12 and 6 times feeding a day, had no statistically significant difference (p>0.05). But the carcass fat content, during 12 times feeding per day in half of treatments, was significantly higher than 6 times feeding per day (p<0.05). The activity of pepsin, trypsin and lipase enzymes, during 12 times feeding a day was significantly more than 6 times a day feeding. Totally, feeding larvae 12 times a day was preferable to feeding 6 times a day, based on improvement of survival of larvae, condition factore and activity of enzymes.

The present investigation elucidates the synergistic effects of improvised ecological parameters and ripe papaya (Carica papaya) meal on skin pigmentation, growth performance and survival of Banded gourami, Trichogaster fasciata, under confined environment. A feeding trial of 60 days was done with initial length groups from 6. 6 to 9. 7 cm using five isonitrogenous experimental diets formulated by supplementing graded levels of carotenoids at 1 to 5% and a control without carotenoids. Two ecological parameters temperature and light intensity were elevated using artificial modulators. At the onset of the feeding trial, the total carotenoid concentration in fish muscle in both male (2. 94± 0. 07 μ g. g-1) and female (2. 54± 0. 05 μ g. g-1), respectively, which significantly increased, highest being in male (6. 86± 0. 12 μ g. g-1) and female (5. 96± 0. 07 μ g. g-1) fishes fed with 4% papaya meal. Positive correlation, (0. 98) in male and (0. 97) female was observed between elevated levels of dietary carotenoids and body pigmentation which revealed that incorporation of dietary carotenoids resulted in a significant increase in total carotenoid concentration in chromatophores. Congenial effects were observed on body indices was revealed by positive correlation of weight (0. 79) to elevated levels of carotenoid and 100% survival rate of the fishes. The feeding regimes showed ripe papaya meal as cheap natural colour enhancer source can be safely supplemented at 4% levels in the diets to increase the skin pigmentation and optimum conditioning in optimized captive environment having temperature range of 26-28oC and light intensity 344. 0-346 Lux, without any xenobiotic effect on Banded gourami.

To examine the combined effects of photoperiod and feeding regime on the growth and off-season parr-smolt transformation of juvenile Caspian brown trout (Salmo trutta caspius), fish of 5. 85± 0. 13g were reared under four different photoperiods (Light: Dark, L: D) cycles (24L: 0D, 16L: 8D, 12L: 12D, 8L: 16D) and were fed with two foods (French and Iranian) which were broadly similar in composition, for 110 days. A CRD design in factorial method including the four photoperiod regimes and two foods, with three repeats and ten fish was used in this experiment. Results showed that fish which fed by both French and Iranian foods grew best and reached to smolt stage faster in (16L: 8D) photoperiod. Although, the higher weight (11. 03± 0. 06g) and length (4. 64± 0. 28 cm) gain were observed in fish which fed by French food, but they did not significantly differ from the fish which fed by Iranian food (P>0. 05). Condition factor (CF) was lower in the 16L: 8D photoperiod than other treatments in both groups of fish without significant difference (0. 84± 0. 06, 0. 89± 0. 01%). Also, the lower feed conversion rates (FCR) was measured in (16L: 8D) in French food which was significantly different from Iranian food. The higher amount of growth hormone was recorded at 17 January and the Na+, K+-ATPase activity was higher at 20 April without significant differences between two groups of fish. Also, the higher amount of growth hormone and ATPase activity were recorded in (16L: 8D) without significant differences between two groups of fish. Our finding indicated that both French and Iranian foods can be recommended in the production of off-season Caspian brown trout smolts in the (16L: 8D) photoperiod.

The feeding habit of Pennahia anea was studied in the north-west of Oman Sea by collecting 188 specimens during years 2010-2011. The samples were collected seasonally with midwater trawls during lantern fish fishing. Vacuity Index (VI), Fullness Index (FI), Gastro-Somatic Index (GaSI) and frequency percentage of different food items were also studied. Of total stomachs, 40 stomachs were full or semi-full and the other 148 were empty. GaSI Index average was 1.1 for the total year. The mean Vacuity Index was calculated 78.7% and amount of Food Preference Index were estimated as: Fishes (92.5%), Crustacean (22.5%) and Molluscs (5.0%). b=3.12 shows isometric growth in the P. anea. It was concluded that P. anea is a relatively abstemious species and its main food was Fishes and minor foods was Crustacean