To introduce Litopenaeus vannamei to Iran as a cultured shrimp species, a experimental study was carried out to assess the effects of different stocking densities on growth rate, mean weight, survival rate, food conversion ratio and the total harvest of l. vannamei. Three postlarval groups (PLI2) of L. vannamei (pond A: 20 PL/m2 , pond B: 30 PL/m2 and pond C: 50 PL/m2) with average size 0.9cm and initial mean weight 0.01±0.005g were used in this study. The experiments were carried out in three replications in 9 earthen ponds each half a hectare in size in Khouzestan province, south of Iran during 110 days. The result showed there was no significant correlation (P>0.05) between stocking density and survival rate in the semi intensive culture condition. Mean survival rate among farms were greatest at the lowest density, where mean survival in pond A, B, and C was 88.6%, 83.3%, 73.3%, respectively but the differences were not significant (P>0.05). The results also showed there was no significant relationship (P>0.05) between growth rate and growth days in each experiment. The mean growth rate/days for ponds A, B, and C were calculated at 0.16g/day, O.l6g/day and 0.15g/day, respectively. The food conversion ratio in the end of the study period for ponds A, B and C was 1.01, 1.17 and 1.2, respectively. Shrimp production increased with an increase in stocking density when farm production at Pond A and B indicated a significant difference (P<0.05) compared to that of the pond C. The total shrimp production for ponds A, B and C was calculated at 2803kg/ha, 3146kg/ha and 3972kg/ha, respectively. The water temperature ranged between 28±3oC to 23±3oC, with the highest in July and lowest in September. Salinity ranged between 25±2ppt to 12±3ppt, pH ranged between 8.6±0.2 to 7.5±0.4 and dissolved oxygen ranged between 5.8±0.4ppm to 5.3±0.3ppm throughout the study. The study proved that L. vanname; could adapt to common conditions in Iranian shrimp culture environment and also we showed that the species production was higher than the native species already under culture.

Juvenile Huso huso with average weight of 28.76±0.35were reared in fiberglass tanks and earthen ponds for 29 weeks in order to examine potential of rearing of the fish for meat production purposes. Fish in fiberglass tanks showed weight increase up to 584.17 grams in 200 days and produced 6 kg of biomass per litre. Survival ratio, food conversion ratio and specific growth rate were measured as 98.4%, 2.21 and 1.41 (% per day) for the fish respectively.During the experiment period, H. huso reared in the earthen ponds reached a weight of 708 grams and produced 1.5 kg of biomass per litre. The survival rate, food conversion ratio and specific growth rate for the fish cultured in the earthen ponds were 85.7%, and 1.32 and 1.69 (% per day). Based on the results, the fiberglass tanks provided better growth condition in the beginning of the experiment. However, in later stages of rearing the trend was reversed and fish reared in earthen ponds showed more suitable condition although no statistically significant differences between treatments were found (p>0.05). Growth pattern of fish was highly influenced by rearing condition (p<0.05). Compared to the fish weight in fiberglasstanks (584.17gr), H. huso weight in earthenpond(708 gr) improved a lot especially after adaptation to concentrated food (p<0.05).

A two-phase random growth test was conducted to evaluate the effects of feeding rate on growth performance, food conversion ratio (FCR), specific growth rate (SGR), feeding efficiency and price index of reared Huso huso fingerlings in fiberglass tanks (2x2x0.53 cm). Rearing conditions such as diet, dissolved oxygen, light, water flow, fish density and feeding frequency were kept similar for the tanks. In the first phase, 180 fingerlings with a mean weight 867.86±17.42g were fed for 100 days in four treatments and three replications at feeding rates 1, 2, 3 and 4 percent of their biomass.In the second phase, also four treatments and three replications were applied to 84 Huso huso with a mean weight 2096.1±35.6g. In this phase, the fish were fed for 125 days with 0.75, 1.5, 2.5 and 3 percent of their biomass. During rearing period, water temperature was 25.52±1.78 and 14.82±0.48 degrees centigrade and dissolved oxygen was 7.6±0.3 and 7.89±0.18mg/lit, for the two phases respectively.The fishes were fed four times daily with a diet containing 40% protein, 13% fat and 9.9% ash. All treatments induced fast growth in the fish, but feeding ratios were different in their effects on the growth (P<0.05). Weight gain percentage, specific growth rate (SGR), food conversion ratio (FCR), feeding efficiency and price index indicated that lower feeding ratios were more effective in causing fish growth (P<0.05). So, increase in feeding ratio directly increased daily food consumption (D.F.C) and negatively affected the feeding efficiency, food conversion ratio, specific growth rate and price index (P<0.05). The results showed that in phase one, when the fish were given food as much as two percent of their body weight, one unit of meat was produced by consuming 1.92 units of food. In the second phase, feeding fish with 0.75 percent of their body weight resulted in producing one unit of fish meat per 1.82 units of food consumed.Also, in the two phases, application of higher than 50% feeding ratio increased costs while no significant trend in fish growth was detected. It can be concluded that regarding the water temperature, the optimal feeding rate for fishes weighing 850 to 1900 grams and those weighing 2050 to 3300 grams are 2 % and 1 % of body weight, respectively.

Background and Objective: Feed shortages, recurrent droughts, and rising costs of fodder and veterinary antibiotics are among the major constraints on livestock production in the country. These challenges have intensified pressure on rangeland resources and contributed to overgrazing. Consequently, one of the main objectives of this study was to evaluate the use of available, low-cost medicinal–forage plants produced using saline water resources and salt-tolerant species with suitable performance, in order to improve forage supply and livestock health. For this purpose, quinoa (Chenopodium quinoa Willd. ) straw—a salt-tolerant plant that can be cultivated on saline lands and is primarily valued for its highly nutritious seeds for human consumption—was used as a forage source. In addition, the resin of Ferula assa-foetida, an important rangeland medicinal plant, was incorporated as a natural antibacterial agent in livestock feed. Methodology: The experiment was conducted at a research farm located in Kohbanan County, Kerman Province. Quinoa forage was used as a partial replacement for alfalfa in the diet of goats. After animal selection and adaptation, the goats were fed diets containing quinoa forage at three levels (0, 30, and 50%) and Ferula assa-foetida resin at three levels (0, 0. 1, and 0. 2%) in a factorial arrangement. A 14-day adaptation period was applied, followed by initial weighing. The experimental diets were then offered as a total mixed ration. Animal growth performance and body weight changes were recorded throughout the experimental period. Daily feed intake and feed refusals were measured, and animals were weighed weekly to calculate weight gain and feed conversion ratio. The experiment was arranged as a factorial design within a completely randomized design with three replications. Data were analyzed using SPSS software (version 27). Treatment effects were evaluated using two-way analysis of variance (ANOVA), and mean comparisons were performed using Duncan’s multiple range test. Results: The results indicated that the treatments had significant effects on total weight gain, average daily gain, and feed intake. Increasing the inclusion levels of both quinoa forage and Ferula assa-foetida resin led to a significant increase in live weight. The highest total weight gain (6. 5 kg) and average daily gain (217 g) were observed in the treatment containing 50% quinoa forage and 0. 2% resin, whereas the lowest values were recorded in the control treatment. The feed conversion ratio was highest (4. 65) in the control group, while the most favorable (lowest) feed conversion ratios were observed in treatments containing 50% quinoa forage combined with 0. 1 or 0. 2% resin. Conclusion: Overall, the results suggest that incorporating medicinal forage derived from quinoa straw and Ferula assa-foetida resin at a ratio of 50% quinoa straw and 0. 1% resin in livestock diets is recommended. This feed combination can serve as a natural alternative to antibiotics, improving animal performance and health while reducing pressure on rangelands. Additionally, this strategy can contribute to lowering feed costs, increasing productivity, and promoting organic livestock production by minimizing the use of chemical drugs.

Extended Abstract Background: Due to the high price of protein sources, breeders are looking for alternative sources that are available at a lower cost. The diet energy supply also has a high cost, most of which is provided by different sources of fat and oil. Some additives, such as Vemozyme enzyme and emulsifiers, increase the availability and digestibility of nutrients, especially protein and fats. Therefore, this research was conducted to investigate the effect of adding multi-enzyme and emulsifier in diets containing rapeseed meal with different energy levels on performance, carcass characteristics, nutrient digestibility, and blood parameter concentrations in broiler chickens. Methods: 800 one-day-old male broiler chickens of Ross 308 strain were reared in a completely randomized design with 2×2×2 factorial arrangement, including two levels of energy (recommended and 100 kilocalories less than the recommended amount), two levels of Vemozyme enzyme (0 and 0.01% of the diet), and two levels of the Lysophospholipid emulsifier (0 and 0.05% of the diet) distributed in 40 experimental units with five replications and 20 birds per replication in three starter (1-10 days), growth (11-24 days), and final (25-42 days) periods for 42 days. Results: Adding the enzyme and emulsifier to diets with high energy levels improved weight gain during the growth period compared to diets with low energy levels. In the final period, weight gain was different using diets with a low level of energy and using the enzyme and emulsifier compared to those with the recommended level of energy without adding the enzyme and emulsifier, or using the enzyme, emulsifier, or both. In the whole period, using diets with low energy levels with enzyme and emulsifier showed no differences in weight gain compared to diets with recommended energy levels without the enzyme and emulsifier. The three interaction effects of the energy level, enzyme, and emulsifier were not significant on feed consumption in all the rearing periods. In the starter period, using the enzyme and emulsifier in diets with recommended energy levels improved the feed conversion ratio (FCR) compared to diets with low energy levels, without using the enzyme and emulsifier. In the growth period, FCR was improved by using diets with recommended energy levels and using the enzyme and emulsifier compared to low-energy diets without additives or using the enzyme, emulsifier, or both additives. In the final period, there were no differences in the FCR using diets with a low level of energy, containing the enzyme and emulsifier, compared to those with the recommended level of energy without adding the enzyme and emulsifier, or using the enzyme, emulsifier, or both additives. In the whole period, the FCR in diets with low energy levels and using the enzyme and emulsifier showed no significant difference with the FCR of diets with recommended energy without additives or using the enzyme or emulsifier. The highest carcass percentage belonged to the use of diets with recommended levels of energy and containing the enzyme and emulsifier. The highest breast percentage was observed for diets with recommended energy levels and enzyme use. The highest percentage of fat in the abdominal area and the highest percentage of gizzard belonged to the control diets with the recommended energy level. Moreover, the highest percentages of liver and pancreas were recorded for diets with recommended energy levels and containing emulsifier. The highest blood triglyceride and VLDL concentrations were found using diets with the recommended level of energy without using the enzyme and emulsifier. The use of emulsifier in diets with recommended energy levels decreased triglyceride and VLDL concentrations compared to diets with recommended energy levels without using the enzyme and emulsifier or diets with recommended energy levels using the enzyme. There were no differences in blood triglyceride and VLDL concentrations when the enzyme and emulsifier were added to diets with low energy levels. Adding the emulsifier to diets with low energy levels led to lower blood triglyceride and VLDL concentrations than diets with recommended energy levels without using the enzyme and emulsifier or using the enzyme or both additives. Diets containing enzymes showed better digestibility of organic matter, crude protein, and crude fat. Using the emulsifier in the diet improved the digestibility of protein and fat. Conclusion: The results of this experiment show that using the multienzyme Vemozyme and emulsifier in diets containing rapeseed meal with energy levels lower than the recommended amount in the final and the whole period can effectively improve the weight, FCR, and the digestibility of crude protein and crude fat. The amount of oil in the diet was reduced by reducing 100 kcal of energy from the recommended amount of energy in the final and growth periods by about 2%, which effectively reduced the cost of the diet.

Effects of stocking density on growth, food conversion ratio, specific growth rate, percentage of body weight increase in Huso huso were studied in two phases. Juveniles below one year old with an average weight of 92.09±1.72 grams and stocking densities of 1.6, 2.8 and 4 kg/m2 in 3 replicates for 100 days were reared as the phase one group. One year old Huso huso with an average weight of 918.13±21.87 grams and stocking densities of 1.5, 2.5, 3.5 and 4.5 kg/m2 reared for 120 days in 2000 liter fiberglass tanks were the second phase. Results revealed negative impact of density on growth, percentage of body weight, and specific growth rate and food conversion ratio in both phases. In the first phase, lower stocking density (1.6 kg/m2) showed significant increase in growth rate (P<0.05) as compared to 2.8 and 4 kg/m2 stocking densities resulting in 42.3% and 61 % growth rate respectively. Fish kept at 4 kg/m2 density showed malformed caudal fins and injured body due to higher tensions and contacts. In the second phase, the growth rate of fish decreased with increase in stocking density where fish with lower density (1.5 kg/m2) showed 7.2%, 15.6%, and 19.8% higher weight gain as compared to fish reared at 2.5, 3.5 and 4 kg/m2 stocking density. Analyses showed that with increase in stocking density, feeding area per fish decreases and tension between fish increases that leads to lower feeding efficiency. Based on the results, the recommended optimum stocking density for Huso huso individuals up to 90 grams is 1.5-2 kg/m2 and for fish individuals over 900 grams each the density should be kept at 2.5-3 kg/m2.

The usage of renewables is growing around the world, and energy production from biomass resources, including food waste (FW) is one of the fields regarding this phenomenon. This paper explores various waste-to-energy (WtE) conversion methods, emphasizing their significance in addressing both waste management and energy production challenges. Biochemical methods such as anaerobic digestion and landfill gas production capitalize on microbial activity to generate biogas from organic waste. Additionally, bioethanol production through fermentation offers a viable route for converting lignocellulosic waste into ethanol. Combustion methods, including direct combustion and waste incineration, harness the calorific value of solid biomass resources for electricity and heat generation. The global application of WtE technologies is assessed, highlighting the increasing adoption of these methods for sustainable waste management and energy production. Comparative analyses reveal the cost-effectiveness and environmental benefits of WtE conversion methods, positioning them as essential components of the renewable energy landscape. Ultimately, this paper underscores the potential of WtE technologies to contribute to a more sustainable and resource-efficient future. Different sets of assessments demonstrate that the concept of WtE will mostly be used in sectors facing challenges in de-carbonization, the global market is going to witness a 20% rise by 2027, and the usage of biomass resources is going to be more than doubled by 2050.

In this article, a novel topology of DC-DC converter based on voltage multiplier cell and coupled inductor with higher efficiency and low blocking voltage across semiconductor is proposed for renewable energy application. The recommended topology obtains a high voltage gain using voltage multiplier cell and one coupled inductor. Only one power switch is utilized in this structure, which reduces the converter's cost. The other benefits of this converter are low number of components, high efficiency due to the zero-voltage switching and the zero-current switching of diodes, and low blocking voltage of the power switch and diodes. Besides, the voltage multiplier cell acts as a passive clamp circuit and reduces the voltage stress across the power switch. Thus, a low rated power switch can be used in the presented topology. Due to the zero-current switching in Off-state, the reverse recovery problem of diodes is reduced. To illustrate the performance and superiority of the presented topology, operation modes, steady-state and efficiency analysis, and the comparison study with other similar converters are presented. Finally, a 160~W experimental prototype with 50~kHz switching frequency and 17 V input voltage are built to confirm the theoretical investigation and effectiveness of the proposed converter.

The present experiment evaluated the effect of density on weight gain and feed conversion ratio (FCR) for rainbow trout in concrete ponds, with use of aeration and well water. Density rates were 44, 62, 76 and 95 Fish/m2, with an average weight 18±3 gr. and two replicates for 135 days. Aeration carried out by an air blower set into the water from ponds floor. The results showed, 44 (as control density) and 62 Fish/m2 significantly (p<0.05) caused higher weight gain (167.6 and 165.25 g/fish respectively) and specific growth rate than other densities and also, better feed conversion ratio. Increasing density caused more mortality. However, under these circumstances the density of 62 Fish/m2 is recommended.

Ninety, day old broiler chicks were randomly divided to three groups including: 1- Intact 2- Sham-operated 3- Caecectomised. When the chicks were 6 days old, the caeca of the chicks in group 3 were surgically removed, and in the sham-operated group, an incision was perfomed on the abdomen of chicks and after little manipulation of intestine, the incision was sutured. The chicks of all groups were reared in the same condition and fed by formulated diets for 49 days. The body weight and feed consumption of the chickens was measured when they were 6(prior to the surgery), 8, 14, 21, 28, 35, 42 and 49 days old. The mean body weight of sham and caecectomised groups, up to day 21 and 35 of their age were significantly lower to the intact group, respectively (P<0.05). But after these ages till the end of rearing period no significant difference was observed between body weight means of the three groups (P>0.05). At the end of every week in rearing period, there was no significant difference between feed consumption and feed conversion ratio in the three groups(P>0.05).According to the results of this study it can be concluded that in the broiler chickens fed by adequate protein and low fiber diet, caeca has no influence on body weight gain and-feed' conversion ratio.