growth performance

 Microelements in organisms have several structural, catalytic, and regulatory functions and play an important role in the functioning of the immune system. The trace mineral content of colostrum and milk is not optimal and in suckling calves, the inclusion of trace mineral supplements in the diet is necessary. Selenium (Se) is a basic mineral for humans and animals and has now been identified as an integral component of more than 35 selenoproteins which are involved in enzymatic, structural, or as yet unidentified functions. In livestock, Se is important for fertility and the prevention of diseases. Sufficient intake of Se increases fertility and enhances antioxidant protection systems and immunological potential. Se deficiency in cattle is associated with several problems, including delayed conception, muscular degenerative disease in calves, myocardial necrosis, heart failure, impaired immune function, increased risk of mastitis, abortion, perinatal mortality, and growth retardation in young calves. Based on the recommendation of the National Research Council, the daily requirements for Se and vitamin E in growing calves are 0.30 mg and 40 IU, respectively. To avoid Se deficiency and to promote animal health, inorganic sources of Se (sodium selenite and selenium) are routinely used as a supplement to the diet of farm animals. Zinc is involved in over 300 enzymes either as a component or as an activator. Zinc (Zn) is involved in immunity, metabolism, growth, and reproduction. It plays a role in the structure and function of antioxidant enzymes. Due to mineral interactions, the inorganic forms are less bioavailable in the gastrointestinal tract. The aim of this study was therefore to assess the effects of supplementation with sodium selenite and Zn oxide on growth performance, immune response, blood parameters, and antioxidant status in Holstein calves.

 The calves were kept in well-ventilated sheds with concrete floors and with individual feeding and watering facilities. The basal diet was prepared from locally available feed ingredients to meet the nutritional requirements of calves growing except for Zn and Se. Calves are fed milk at 10% of body weight in the morning and evening. The experiment started at four days of age and the calves were kept in individual pens for up to 42 days. The study used 36 Holstein calves with an average weight of 34.5±2 kg over 42 days in a completely randomized design. The basal diet (containing 40 mg Zn and 0.15 mg Se) was without Zn and Se supplementation (diet 1). Diet 2 contained 0.3 mg sodium selenite, diet 3 contained 40 mg Zn oxide, diet 4 contained 55 mg Zn oxide, diet 5 contained 0.3 mg sodium selenite + 40 mg Zn oxide, and diet 6 contained 0.3 mg sodium selenite + 55 mg Zn oxide. Feed intake was calculated daily, and calves were weighed weekly to calculate the feed conversion ratio and average daily gain. Blood samples were taken on days 20 and 42 to determine trace mineral levels in plasma and biochemical, enzymatic, hormonal, antioxidant, and hematological parameters. Data on growth and blood parameters were analyzed using the GLM procedure of the SAS program. Significant difference between treatments was determined by Duncan's test and the results were considered significant if the P-value was less than 0.05.

 The results showed that the use of sodium selenite and different levels of Zn oxide did not have a significant effect on feed intake, final weight, body weight gain, growth performance, and immune response (P>0.05). No significant differences in blood metabolite concentrations were observed between treatments (P>0.05). Supplementing milk with 0.3 mg sodium selenite and 40 and 55 mg Zn oxide significantly increased the activity of superoxide dismutase and decreased the levels of malondialdehyde and aspartate aminotransferase (P<0.05). Se plays a role in the defense against the accumulation of hydroperoxides from cellular metabolism. This biological function is mediated by selenoproteins such as glutathione peroxidase (GPx), iodothyronine deiodinases, and thioredoxin reductases, of which selenium is a structural component. Se also acts on enzymes involved in the production and regulation of thyroid hormones and is recognized as a factor in immunological function. The role of Zn as an antioxidant and its role in cell replication and proliferation are the two most directly related links between Zn and the immune system.

 Supplementing milk with Zn oxide and sodium selenite improved the antioxidant status and helped to relieve the stress experienced by suckling calves.

 Animals need vitamins A, D3, and E to improve their performance and health. Vitamin A has an active role in maintaining all epithelial cells in the body and plays an important role in bone growth. Vitamin D3 plays an important role in increasing the absorption of calcium and phosphorus, in addition to the formation and calcification of the bones in animals. Vitamin E is a fat soluble vitamin which is both a growth-promoting vitamin and is considered an antioxidant. These vitamins also play an important role in improving the immune system in ruminants. Ruminants cannot produce vitamins A, D3, and E in their body; therefore, to meet physiological requirements and maintain high production performance, they need to be provided with an exogenous regular intake of vitamins A, D3, and E in their diet. Several studies have been carried out on the effects of dietary or injectable vitamin AD3E supplements on fattening lambs. This study aimed to determine the effects of various forms of AD3E supplementation on growth performance, rumen fermentation, protozoa population, and blood parameters in Mehraban lambs by in vivo and in vitro experiments.

 The project comprised two in vitro and in vivo experiments. In this experiment, the in vivo growth parameters such as final body weight, total weight gain, average daily gain, average daily gain, dry matter intake, feed conversion ratio, the ruminal fermentation parameters such as pH, ammonia nitrogen, total volatile fatty acids, blood biochemical metabolites [blood urea nitrogen (BUN), cholesterol, triglyceride, glucose, albumin, HDL, LDL, and malondialdehyde (MAD)], protozoa count, and in vitro gas production, organic matter digestibility, methane gas production, metabolizable energy, and short-chain fatty acids were studied. This experiment consisted of a 14-day adaptation period and a 60-day experiment. Twenty Mehraban lambs (body weight of 41.3±0.5 kg) were divided into four groups with five replicates in each group using a completely randomized design. The treatments included 1) the control group received a base diet without vitamin supplements, 2) injectable vitamin AD3E, 3) rumen-protected vitamin AD3E as a part of concentrate, and 4) AD3E vitamin in drinking water. Feed intake and body weight of lambs were recorded weekly during the fattening period. The samples of blood and rumen liquid were collected from the lambs on the 30th and 60th days of the experiment.

 The results indicated that the gas production, digestible organic matter, metabolizable energy, and short-chain fatty acids were reduced due to vitamin AD3E supplementation compared with the control group (P<0.05). Growth performance was not different when supplemented with AD3E, but for the rumen-protected vitamin, the average daily increase was 48 g more than that in the control group. The feed conversion ratio showed a significant decrease in AD3E water-soluble vitamins compared with the control group (P<0.05). The pH was not influenced by experimental treatments. The ammonia concentration was higher in treatments 3 and 4 (P<0.05), and the protozoa count was reduced due to vitamin AD3E supplementation (P<0.05). The BUN serum concentration was lower in treatments 2 and 3 compared with other treatments (P=0.008). Vitamin supplementation with AD3E administered in water or its injection made a significant increase in cholesterol concentration (P=0.002). Blood concentration of triglyceride showed a significant increase in treatment 4 (P=0.007). Plasma concentration of HDL was lower in lambs who received rumen-protected AD3E compared to the control group (P<0.05). Experimental treatments did not affect plasma glucose, total protein, albumin, LDL, and MAD concentrations of fattening lambs (P>0.05). Plasma concentration of BUN on day 60 was higher compared to the 30th day in all treatments (P<0.05). However, plasma concentrations of triglyceride and glucose were lower on day 60 compared to the 30th day of the experiment in all groups.

 Results showed that vitamin AD3E had no significant effect on growth performance; however, it was greater in the vitamin group treated with rumen protection than in the control group. Gas production, protozoa population, and ammonia nitrogen decreased compared to control. Higher doses of vitamins, especially the rumen-protected vitamin AD3E, are recommended in larger sample sizes and for longer periods.

Glutamine represents approximately 30-35% of the total amount of nitrogen in the blood derived from amino acids. The role of glutamine as a nitrogen shuttle helps to protect against the toxic effects of high levels of ammonia in the blood. In addition, glutamine has vital and specific metabolic functions as a vehicle for carbon exchange between tissues, as a fuel for rapid cell division, and as a precursor of many naturally active molecules. It's a great example of how amino acids are used for different purposes in the metabolism and the immune system of the body. Glutamine, a conditionally essential amino acid, seems to be a key nutrient for the gut, as it may be a prominent source of vitality for the enterocytes. Glutamine appears to trigger an increase in the level of intestinal secretory immunoglobulin A, which is essential for mucosal defense. The investigation showed that the use of amino acid supplements in broiler diets improves the performance and the carcass characteristics. Glutamine is one of the most abundant amino acids in blood plasma and is involved in the building of muscle, and tissue, and gaining body weight. Researchers found that adding 10 g of L-glutamine per kg of food increased the weight gain and serum immunoglobulin A and G concentrations in broiler chickens. Therefore, an experiment was carried out in broiler chickens over 42 days of production to determine the effect of L-glutamine on broiler growth, carcass quality, and certain blood parameters.

The experiment was conducted using 300 one-day-old male Ross 308 broiler chickens in a completely randomized design with five treatments and five replicates from the age of 1 to 42 days. The experimental treatments included were: the addition of zero, 0.25, 0.5, 0.75, and 1% of L-glutamine in corn-soybean meal-based diets supplemented with dietary fat. During the experimental period, average daily feed intake (DFI), body weight gain (BWG), and feed conversion ratio (FCR) were measured. At the end of the experiment, two birds were selected from each replicate and slaughtered after weighing, and the weight of the internal organs (thigh, breast, heart, liver, gizzard, fat pad, pancreas, bursa, spleen, and thymus) was measured. Blood samples were collected from two birds per replicate to determine the number of white blood cells (WBC), and heterophile to lymphocyte ratio (H/L). Blood samples were taken from the jugular vein in tubes without anticoagulant and then centrifuged (2000×g for 10 min) to obtain a serum. On the 42nd day of rearing, serum cholesterol (total cholesterol, low-density lipoprotein (LDL), and high-density lipoprotein (HDL)) and triglycerides were determined by calorimetric examination.

Weight gain during the initial and growth periods was affected by L-glutamine supplementation (P<0.05). Despite higher feed intake for L-glutamine-supplemented diets during the initial period, this effect was significant only during the growth period (P<0.05). FCR and relative weight of internal organs, except liver weight, were not significantly different from the control group in the L-glutamine-supplemented chickens. The addition of 0.5% L-glutamine supplementation reduced cholesterol and triglyceride content and increased HDL in the blood of broilers (P<0.05). The H/L ratio in chickens that consumed L-glutamine was significantly lower than in the control group (P<0.05). L-glutamine has been reported to increase the activity of the intestinal enzyme Na-K ATPase, thereby indirectly increasing the absorption capacity of nutrients such as glucose and amino acids in the intestine. Researchers reported that L-glutamine increases the performance and feed intake of chickens by improving intestinal function and increasing digestibility. Expanding the villi of the small intestine can increase digestion and feed intake by increasing nutrient absorption and thus improving chicken performance. Improving the morphology of the digestive system is one of the possible mechanisms of the positive effect of L-glutamine on improving weight. Since glutamine stimulates anabolic conditions in the body and increases the amount of protein synthesis, therefore, along with muscle growth, it can increase the final body weight. Avian health is directly related to the immune system, and birds with adequate immune systems grow better. The majority of essential amino acids are recognized as critical resources for cytokine production and immune function.

Results from this study indicate that 0.5% dietary glutamine supplementation improved growth performance and had a positive effect on lipid metabolism-related blood parameters.

This research aimed to assess the effect of feeding Salicornia bigelovii fodder on the growth and carcass performance of fattening lambs. The experiment was conducted using 63 male Afshari lambs in a completely randomized design with seven treatments and nine replications for 100 days. The treatments were diet without Salicornia (control) and diets containing levels of 45, 90, 135, 180, 225, and 270 g Salicornia, instead of alfalfa/kg DM. Compared to alfalfa, Salicornia contained lower amounts of protein, nitrate, and neutral detergent fiber (NDF), but higher content of ash, sodium, oxalate, and phenolic compounds. Feeding increasing levels of Salicornia caused a linear increase in daily water consumption (P<0.05). Daily intake of DM increased with increasing Salicornia levels (P=0.05), but consumption of organic matter (OM) and crude protein did not differ. Salicornia feeding had no significant effect on daily growth and feed conversion based on diet OM, but at levels of 135 g and more, it caused a decrease in feed conversion based on diet DM. Digestibility of DM (P=0.072) and ash (P=0.012) increased and NDF digestibility decreased (P=0.048) with increasing Salicornia consumption, but the digestibility of OM, crude protein and ether extract, and carcass yield did not change. Overall, feeding Salicornia up to 270 g/kg diet DM (with a forage-to-concentrate ratio of 40:60) increased the water consumption of animals, but it did not have a negative effect on the performance of fattening lambs, and it can be recommended to replace a portion of the diet forage in male Afshari sheep.

In the present study, a total of 336 one-day-old broiler chickens (Ross 308 strain) were used in a completely randomized design with four treatments to evaluate the effects of barley rootlets (BR) as a feedstuff in broiler nutrition. Dietary treatments consisted of a control group based on corn and soybean meal, along with three additional treatments, similar to the control but including 1.5, 3.0, and 4.5% BR. Feeding diets containing BR impaired broiler growth performance as reflected in poor feed conversion ratio and body weight gain. Inclusion of BR at 4.5% significantly increased digesta viscosity in jejunum and reduced the villus height to crypt depth ratio with concomitant increase in the moisture content of the litter. In conclusion, the use of BR can be limited up to 1.5% and the levels above that impair broiler response. Poor growth performance resulting from BR was associated with reduced feed consumption, increased viscosity of intestinal contents, and reduced villus height to crypt depth ratio. Levels of BR above 4.5% caused poor litter quality as indicated by higher moisture content in the litter.

This experiment was carried out in order to investigate the effect of adding different levels of Zirfon flower powder to the diet on growth performance, blood biochemical parameters, immune system status and antioxidant indices of broiler chickens during 3 periods for 42 days. The number of 300 one-day-old chicks of ROSS-308 strain was assigned to 4 experimental treatments with 5 repetitions and each repetition with 15 chickens in the form of a completely random design. The experimental treatments included 1) control diet (without additive), 2) control diet + 1% Zirfon flower powder, 3) control diet + 2% Zirfon flower powder and 4) control diet + 3% Zirfon flower powder. The results of the experiment showed that the amount of feed intake in the entire breeding period in the treatments containing 2 and 3% of Zirfon flowers was significantly increased compared to the control treatment (P<0.05). The amount of total serum protein, antibody titer produced against sheep red blood cells, number of lymphocytes and percentage of carcass in the treatment containing 3% of Zirfon flower had a significant increase with the control treatment (P<0.05). Also, the addition of different levels of Zirfon flower to the diet, significantly increased the concentration of glutathione peroxidase enzyme in the liver tissue (P<0.05). Based on the results of this experiment, 3% of Zirfon can be considered as an additive that stimulates feed intake and improves the immune system and antioxidants in the diet of broiler chickens.

Tomato is a valuable vegetable that is rich in vitamins such as vitamin A, E, C, B and K, and also some of minerals such as phosphorus, iron, calcium, which are important for metabolic activities. Tomato pomace is a byproduct that produce in the tomato paste production. The composition of tomato pomace in terms of percentage of crude protein, crude fat, lycopene, beta-carotene, ascorbic acid, alpha-tocopherol, lycopene and beta-carotene are: 11%, 4.5%, 0.8 mg, 13. 0 mg, 1.73 mg, 0.07 mg and 281 and 24.3 mg per kg of dry matter respectively. The antioxidant capacity of tomato pomace is related to the substances in it, especially lycopene, which reduces the effect of reactive oxygen species and the destructive effects of these compounds on the cell membrane and mitochondrial structure. Tomato pomace has a high fiber content, which may have undesirable effects on broiler performance. This meta-analysis is a systematic review based on previous studies. The aim of this meta-analysis was to examine the effects of tomato pomace on growth performance and selected blood indices in broiler chickens.

In order to collect the required information, a comprehensive search was conducted among articles and thesis through Persian and Latin databases using keywords, tomato pomace, carcass efficiency, cholesterol, heterogeneity test. Studies (available data) in the field of using tomato pomace in Farsi and English were collected and categorized. The search was done in various databases, including PubMed, ISI Web of Science, Irandoc, etc. In the next step, the most frequently reported data from the reviewed articles that aligned with the research objectives were selected. The study area was refined by identifying the influencing factors and attributes relevant to the meta-analysis. The data were then coded, and after an initial review and removal of duplicates, a total of 12 studies were included in this meta-analysis. Among these, 9 comparisons were conducted for feed conversion ratio, 10 for feed consumption and body weight gain, and 4 for carcass characteristics and efficiency. Additionally, comparisons were made for the percentages of heart and liver, blood lipid levels, blood glucose levels, and total protein concentrations. Then the statistical analysis of the data was done in the CMI (CMA) software. Both fixed and random effects models were used to combine the effect size. To evaluate the publication basis, funnel plot and statistical tests on Tomato pomace were used.

The abdominal fat percentage (-0.354±1.44), heart percentage (-0.353±0.294), pancreas percentage (-0.504± 0.316), gall bladder percentage (-0.027± 0.961), glucose (-0.091± 0.331), LDL (-1.942±0.644), total protein (-1.505± 0.003), cholesterol concentration (-0.290±0.04), feed intake in starter (0.072± 0.531) were lowered when tomato pomace were added to the broiler diet. The effect of inclusion of tomato pomace on weight gain during the growth period, feed intake in all periods and FCR in the starter, grower, and finisher period, the blood concentration of triglyceride, glucose, and the percentage of abdominal fat, liver, heart, pancreas and gall bladder, also breast was not significantly affected by tomato pomace. Some researcher also reported that inclusion of tomato pomace to broiler diet did not effect on broiler performance however in the high levels of tomato pomace in broiler diet observed undesirable effects. Tomato pomace has some bioactive components such as alpha-tocopherol, lycopene, phenolic, organic acids, essential fatty acids, amino acid and vitamins. However, there is a higher concentration of crude fiber in tomato pomace.

Therefore, the findings of the present study show that application of tomato pomace has a significant effect on weight gain in the starter, total and finisher periods, FCR in the total and finisher period, total protein, cholesterol, HDL, LDL concentration. It is recommended that tomato pomace can be replaced the part to broiler diet.

Groups feeding vs. individual feeding of animals has been a controvesial subject among nutritionists for many years. Some believe the psychological effect on animals, being housed individually or in groups influence the results of experiment, some have found that effect to be depended on the ration fed. Individual feeding of animals is important in nutritional and biological research. In addition, individual data have statistical advantages in the number of degree of freedom with an equal number of animals and in identifying individual variation. 16 Dalagh lambs with an average age of 3 months and weight of 1 22±2 with 2 treatments and 8 replications were used in a completely randomized design. The treatments include: 1- individual nutrition and 2- group nutrition. The duration of the trial period was 90 days, which included 14 days of habituation. The lambs of treatment one were kept individually in individual stalls and the lambs of treatment two were kept in groups. During the entire experiment, the animals had free access to clean drinking water and the daily feed was completely mixed in two meals (at 8:00 AM and 4:00 PM). The feed conversion factor was calculated by dividing the average daily dry matter intake of each lamb by the average daily weight gain of the same animal. The samples collected from each lamb were mixed and one sample was used for the chemical analysis of feces. Dry matter digestibility was calculated using acid-insoluble ash as an internal marker. Also, blood sampling was done on the last day of the test period and before the morning meal with 12 hours of food restriction, at the rate of 10 cc from the jugular vein and without the use of anticoagulant. To measure the feed consumption activity on the last day, the lambs were observed for 24 hours and the behavior of eating, ruminating, chewing and resting was observed and recorded.Experimental treatments had no significant effect on daily feed consumption, daily weight gain and feed conversion ratio. Also, group and individual feeding could not have a significant effect on the amount of digestibility of dry matter and organic matter, but its amount increased insignificantly in the treatment with individual feeding compared to the treatment with group feeding. The behavior of chewing, resting and ruminating was not affected by the group and individual feeding methods, but the eating behavior was affected by the treatments and its amount increased significantly in group feeding. The reason for this increase can be attributed to the competitiveness of eating and the effort to have better and constant access to food in group feeding than in individual feeding where eating food is not competitive. The experimental treatments had a significant effect on the amount of glucose (P=0.0169), but the amount of cholesterol, triglyceride and urea nitrogen was not affected by group and individual feeding of lambs. The amount of cholesterol in individually fed lambs was insignificantly higher than group fed lambs. Probably, individual animals are involved in metabolic stress compared to group animals, and during the period of stress to meet the high metabolic demand of body tissues, changes in the level of serum lipids, especially cholesterol, are made, and the level of serum cholesterol also changes. Increase. In general, the results showed that group feeding had no significant effect on the performance of lambs compared to individual feeding. In general, the results showed that group feeding had no significant effect on the performance of lambs compared to individual feeding.

The study of the effects of macroalgae extract and probiotics of the Bacillus species on the Pacific white shrimp for improving aquaculture practices, enhancing shrimp health and growth, effectively managing diseases, and promoting sustainability in the industry is vital. These findings could lead to significant advancements in shrimp farming and contribute to the overall success of aquaculture. This research examines the combined effect of a blend of brown macroalgae extracts (Padina astraulis, Sargassum ilicifolium, and Stoechospermum marginatum) and the single-cell probiotic (Bacillus subtilis IS0) on the growth performance and digestive enzyme activity of whiteleg shrimp, Litopenaus vannamei. A total of 2400 post-larvae with an average weight of 1.02±28.9 mg were randomly divided into eight groups of 100 shrimp each (with three replicates per group). The control group received a diet without macroalgae extract (MPE) or probiotic (P), while the other groups received diets containing different amounts of macroalgae extract (15 kg-1) and different concentrations of probiotic (1, 2 and 3 g 100 g-1 diet). Some groups also received combinations of the macroalgae extract and the probiotic at fixed concentrations. This feeding regimen lasted for 60 days. Spectrophotometer kits and devices were used to measure the activity of digestive enzymes.The results showed that the groups fed with P2+MPE and P3+MPE had the highest specific growth rates, final weights and weight gains, showing significant differences when compared with the control group and other experimental groups (P<0.05).In addition, these two groups also had the lowest feed conversion ratios. However, the survival rates of the experimental groups were not significantly different (P>0.05). The highest enzyme activities were found in the group receiving P2+MPE, with lipase at 8.33±11.0 U mg-1 protein, amylase at 543.33±15.27 U mg-1 protein and protease at 488.66±10.21 U mg-1 protein (P<0.05). Overall, the combined use of brown macroalgae extract at a concentration of 2 g 100 g-1 diet resulted in improved growth performance and increased digestive enzyme activity in white leg shrimp.

In this study, the effects of low protein diet containing 0 (control), 2 (B1), 4 (B2) and 8% (B3) Saccharomyces cerevisiae on growth and immunity performance of common carp and water quality of culture system were evaluated for 56 days. The 204 fish with the mean weight of 13.14±0.33 g were distributed into 12 culture tanks in triplicates. The results showed that 2% of yeast in the diet (B1) can improve the final weight (25.05±0.92 g) (P<0.05) and reduce the food conversion ratio (1.21±0.08). Also, in the treatment of 2% yeast (B1), the activities of digestive enzymes amylase, lipase and protease intestinal had a statistically significant increase compared to other experimental treatments (P<0.05). The diet containing 2% yeast significantly increased the activity of lysozyme and total immunoglobulin in serum (26.47±0.42 u/ml/min and 16.02±0.11 mg/ml, respectively), while serum ACH50 had no statistically significant difference among treatments (P≤0.05). The total ammonia (TAN) concentration was significantly lower in B1 and B2 biofloc treatments compared to other experiments (P<0.05). Based on the present results, the diet containing 2% yeast in treatment B1 can improve the activity of digestive enzymes, growth performance and immune responses of common carp grown in biofloc environment.

This 70-day experiment examined the effect of protease added to the commercial feed of Sterlet (Acipenser ruthenus) at concentrations of 0 (control group), 75 mg (T1 treatment), 150 mg (T2 treatment) and 300 mg (T3 treatment) per kg of diet on growth parameters and carcass composition. a number of 180 juvenile Sterlet with an average body weight of 6.02±0.34 g was randomly divided into 12 fibreglass tanks with stocking density  of 15 fish per each tank. At the end of the experiment, growth parameters indicated a significant difference between experimental treatments compared to the control group (p<0.05). The highest final weight (66.45 ± 0.33 g), weight gain (59.44 ± 0.52 g), specific growth rate (1.39 ± 0.02 %/day), protein efficiency ratio (2.43±0.11) and the lowest food conversion ratio (0.84±0.04) were measured in T3 treatment. However, the highest amount of condition factor (2.34±0.08%) was recorded in the T2 treatment (p<0.05). The carcass composition showed a significant increase between all the investigated indices in the experimental treatments compared to the control group (p<0.05). The highest amounts of dry matter (26.54±0.06%) and crude protein (15.27±0.02%) were measured in the T3 treatment. The highest amount of crude fat (8.07±0.05%) was in the T1 treatment. The highest amount of ash (2.27±0.02%) was observed in the T2 treatment. Based on the obtained results, it can be concluded that protease in concentrations of 75 to 300 mg per kg positively affected the growth and chemical composition of carcass A. ruthenus.

Aquaculture development is challenged with limitation and high costs of supplying protein diets, so searching for alternative protein sources in fish diets is inevitable (Tacon, 2020). Insect meals are considered as a promising substitution protein ingredients last decades (Alfiko et al., 2022). Among candidates’ insect meals, Silkworm is well-balanced in protein as well as lipid and can be served as feedstuff (Mahanta et al., 2023). A study conducted to investigate if low level of silk worm pupa inclusion in fingerling Beluga sturgeon (Huso huso) diet could provide a protein source replacement accompanying with high benefit for the species.

Fingerling Beluga sturgeons (5±0.2 g, mean±SE) fed with experimental diets for a period of 8 weeks. Four experimental diets includes: no (SWP) inclusion as a control treatment (T0), 5, 10 and 15 percent (SWP) substitution referred as (T5, T10 and T15) treatments. At the end of the experiment, Weight Gain (WG), Specific Growth Rate (SGR) and Feed Conversion Ratio (FCR) calculated to assess the diets quality on fish production. Hepatic enzyme (ALP, AST, and ALT) and serum biochemical (IgM, total protein and lysozyme) analyzed for revealing the health status of fish.

(SWP) treatments, in particular (T15) had a significant increase in (WG) compared to the control group (p<0.05). (SGR) as well as (CF) in (SWP) treatments showed no significant differences compare to the (T0) (p<0.05). (FCR) was significantly improved among (SWP) treatments, although the difference was not significant (p<0.05). Serum lysozyme, Serum immunoglobin and total protein in (T10) and (T15) were significantly increased compared to the control group, (T0) (p<0.05).

Our findings indicate the protein level adjusts and fixes with the (SWP) was efficiently enough to be replaced with fish meal in fingerling Beluga sturgeon (H. huso). The results of (SGR) as well as (CF) suggest that the replacement level could be changes to more to get a differently improved result. Hepatic enzymes showed that (SWP) did not affect impairment in digestive tract.  What’s more, blood biochemical analysis showed that (SWP) can have immunomodulatory effects on fingerling Beluga sturgeons (Zhou et al., 2022)

In fish farming industry, the use of nutritional supplements, including enzymes, is recognized as a vital strategy to enhance nutritional performance and growth. This study aimed to evaluate the effect of enzymatic extract from pyloric appendages on the growth performance and body composition of rainbow trout fry. Four dietary treatments were prepared, including a control diet (A: without enzyme) and three diets containing different levels of enzyme extract (B: 0.5 g/kg, C: 1 g/kg, and D: 2 g/kg of feed) with uniform protein and energy content. The results indicated that diets D and C exhibited the best growth performance compared to other experimental diets. These diets significantly outperformed others in terms of body weight increase and daily growth rate. Moreover, they showed the best feed conversion ratio, indicating efficient feed utilization. Additionally, diet D showed the highest specific growth rate and condition factor, while diet C exhibited the highest survival rate, although these differences were not statistically significant. The ash content in diet D was also significantly higher compared to other diets. Diets D and C significantly increased protein efficiency ratio and lipid efficiency ratio. The findings suggest that the inclusion of 2 g/kg enzymatic extract from pyloric appendages can improve the growth and nutritional performance of rainbow trout fry.

Studies on nutrient utilization and growth performance of Beluga (Huso huso) raised on five feeding schedules (treatment 1 continuously fed plant protein diet, treatment 2 continuously fed fish meal diet, treatment 3 alternate feeding of a 1-day plant protein diet; followed by a 1-day fish meal diet, treatment 4 plant protein diet in the morning fallowed by fish meal diet in the afternoon and treatment 5 fish meal diet in the morning followed by plant protein diet in the afternoon) in 3 replication (20 fish in each repetition) under laboratory conditions showed that continuous feeding with Fish meal diet (treatment 2) resulted in maximum growth, which was not significantly different from treatments 4 and 5 (p<0.05). While feeding with plant protein diet (treatment 1) and feeding every other day (treatment 3) led to a decrease in fish growth performance (p<0.05). In terms of protein digestibility, the best treatments were 2, 4 and 5, which did not show any significant difference with other treatments (p<0.05). The highest amount of muscle arginine belonged to treatments 2, 4 and 5, which was significantly higher than muscle arginine of fish fed with treatments 1 and 3 (p<0.05). Also, the highest amount of glycine was observed in treatment 5, which was not significantly different from other treatments except treatment 1. No significant difference was observed in the amounts of other muscle amino acids of the experimental treatments (p<0.05). The obtained results showed that the alternating change of the dietary protein source during one day (morning and evening and vice versa) does not have any negative effect on the growth performance and feed efficiency, and in most of the nutritional factors, it is equal to the treatment fed with fish meal.

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.

Lamb fattening is one of the important sources of red meat production in the country. Fattening is the management and proper feeding of livestock to obtain maximum extra weight with minimum cost in a certain period of time. The use of concentrate in the diet of fattening lambs in the country is normal and common, but what is important is the appropriate level of concentrate, or in other words, the appropriate ratio of forage to concentrate in the diet. The purpose of this study was to investigate the effect of increasing the ratio of concentrate to forage on feed intake traits, body weight, feed conversion ratio and carcass characteristics of Afshari fattening male lambs.

The present study was conducted using 24 male lambs with a mean weight of 31.78 ± 1.3 kg and a mean age of 91 ± 3.13 days in four experimental groups (treatments) in a completely randomized experimental design with three treatments and 8 replications. The experimental treatments included diets with different ratios of forage to concentrate in the form of 30:70, 20:80 and 10:90. The experimental diet was set based on of NRC (2007) and the ingredients of the diet and their nutritional value were similar. Lambs were fed three times a day at 8, 14, and 20 until their appetite. The lambs were weighed at the end of the experiment after 16 hours of feed abstinence and six lambs from each treatment were killed. Study data was analyzed through Spss21, Excel.

A significant difference was observed between different treatments in terms of weight gain. The third treatment produced the highest daily weight gain (296 g) and the first treatment produced the lowest daily weight gain (241 g) in lambs. With the increase of concentrate, the feed intake increased due to the higher content of energy and nutrients of the concentrate compared to the forage, and the lambs that consumed more concentrate had higher body weight and slaughter weight. So that the highest amount was related to 90% concentrate and 10% forage (1.830 g) and the lowest was related to 70% concentrate and 30% forage (1.573 g). The fourth treatment had a numerically lower feed conversion ratio (6.18) compared to the other two treatments. The mean final weight of lambs, hot and cold carcass weight showed a significant difference among experimental treatments.

According to the obtained results, the reduction of forage did not cause any production problems in these animals. Increasing the concentrate and reducing the forage in the diet increases the amount of feed intake and increases the daily weight and overall higher final weight in fattening lambs, and also improves the feed conversion ratio, growth performance and carcass percentage.

The aim of this experiment was to investigate the effects of dietary artichoke level on growth performance, nutrients digestibility and plasma parameters in fattening male lambs. Twenty-four Kurdish lambs (30.18 ± 2.35 kg BW and 7 months age) were used in a completely randomized design. Experimental diets were diet containing 0% artichoke (control), diets containing 10 and 20% artichoke respectively. The experiment was lasted for 100 days including 20 days for adaptation period and 80 days for data recording and samples collection. Results showed that lambs fed diet containing artichoke had greater average daily gain and feed efficiency compared to the control group (P<0.05). Digestibility of dry matter (P=0.09), organic matter (P=0.09) and crude protein (P=0.10) tended to increase linearly with increasing artichoke level in the diet, whereas digestibility of neutral detergent fiber was not affected by artichoke level in the diet. Lambs fed diets containing artichoke had lower blood urea concentration compared to those fed control diet (P<0.05), but plasma glucose, total protein, albumin, globulin, cholesterol and triglyceride concentrations were not affected by the experimental diets. It is concluded that feeding artichoke up to 20% of total mixed ration not only had no negative effect on feed intake and nutrients digestibility but also improved growth performance of fattening lambs.