Increase In Growth Performance Research Articles

Impact of Temperature on the Growth Performance, Survival Rate, Osmoregulation, Dissolved Oxygen and Physiological Changes of Freshwater Tilapia (Oreochromis mossambicus)

For many aquatic species, any changes in water temperature affect their survival. This study was performed to investigate the effect of rising temperature on the growth parameters, protein content, dissolved oxygen content, moisture content osmoregulation, and physiological activity of freshwater Tilapia (Oreochromis mossambicus). The experiments were set in plastic fish tanks, the experimental tank placed in direct sunlight and the control tank in shade, and measuring temperature and pH daily, with proper aeration and feed was provided. The study found that increasing water temperature led to higher mortality rates and low survivability percentages in fish, with a higher growth rate in the experimental group with a pH range of 5.7 to 8.2. High dissolved oxygen levels were recorded during the experimental period, with a mean difference of 26.56 compared to the control group, possibly causing restless movement in fish. The study revealed that the alkalinity of water decreases with increasing temperature. The study found that increased salinity led to a significant increase in growth performance, indicating an increase in metabolic rate, and a decrease in alkaline nature. The difference between the mean protein value in the experimental and control groups is 0.896mg/ml. Thermal limitations may negatively impact O. mossambicus physiological responses, impacting aquaculture production due to predicted global climate change-induced water temperature changes.

A study of the immunomodulatory effects of coconut oil extract in broilers experimentally infected with velogenic Newcastle disease virus.

This study aims to evaluate the immunomodulatory effects of coconut oil extract (COE) in broilers experimentally infected with velogenic Newcastle disease virus (vNDV). A total of 150 broiler birds (day-old) were equally divided into five study groups i.e., negative control, positive control, COE-1, COE-2, and COE-3. On day 10, broilers of groups COE-1, COE-2, and COE-3 were supplemented with 1, 2, and 3 ml of COE respectively per liter of drinking water for 15 days. On day 13, 0.1ml/bird (10-5.25 ELD50) of vNDV was inoculated in broilers of positive control, COE-1, COE-2, and COE-3 groups intramuscularly. During this study, growth performance, morbidity, and mortality rates of each study group were recorded. The antibody titer against NDV was determined on days 7, 14, 21, 28, and 35. The levels of IgY and IgM were also determined on the 7th, 14th, and 21st days post-SRBC inoculation. On day 33, avian tuberculin was injected between the 1st and 2nd toes of the left side (intradermally) to measure lymphoproliferative responses. On day 35, the phagocytic activity in the blood was assessed through a carbon clearance assay by injecting carbon black ink into the right-wing vein. The visceral organs having gross lesions were also collected for histopathology. The COE significantly improved the growth performance, and lowered the morbidity and mortality rates of broilers. There was a significant rise in antibody titers against NDV and levels of IgY and IgM antibodies against SRBC in COE-supplemented broilers. The lymphoproliferative response and phagocytic activity were also enhanced. Among COE-supplemented groups, the broilers of the COE-3 group showed a significant increase in growth performance and boosted immune defense. Coconut oil extract has the potential to boost the growth performance and immune status of broilers. It can be used effectively as a feed additive and alternative to antibiotics to prevent the spread of infectious poultry pathogens.

Effects of Different Feeding Durations on Ileum Length and Weight and Basal Endogenous Loss of Phosphorus in Broiler Chickens Fed a Phosphorus-Free Diet.

The study investigated the effects of feeding duration on the length and weight of the ileum, and basal endogenous loss (BEL) of phosphorus (P) on broiler chickens fed a P-free diet (PFD). A standard starter diet was fed to 384 birds for 15 days. On day 15, they were weighed and randomly allocated to one of three treatment groups in a randomized complete block design, with eight replicate cages per treatment and 16 birds per cage. The birds in each treatment group were fed the PFD for 2, 3, or 4 days. There was an increase in growth performance (p < 0.05) as the PFD feeding duration increased from 2 to 4 days. Although the relative dry weight of the ileum (mg/100 g of body weight) decreased linearly (p < 0.05) as the PFD feeding duration increased, the amount of dried ileal digesta (g/bird) was not affected. The BEL of P was 110.2, 128.2, and 133.6 mg/kg of dry matter intake in birds fed the PFD for 2, 3, and 4 days, respectively. Feeding a PFD to broiler chickens for 2, 3, or 4 days did not change P BEL.

English

Mango (Mangifera indica L.) is widely grown as an agroforestry tree in different parts of the world especially in Ethiopia. However, its dense canopy and expected allelopathic effect make it very difficult to survive for many of the associated crops grown under it. Therefore, current study was undertaken with the main objective to investigate the allelopathic and shading effects of mango on the germination and early growth performance of food crops and medicinal plants. Leaf extract of mango was tested to find out its inhibitory or stimulatory effect on maize, pea nut and haricot bean with varying concentration of extracts (0, 10, 15 and 20%) at lab and pot study. Results of the study witnessed the inhibitory effects of its extract on germination and early growth performance of cereal and pulse crops for most of the parameters studied. However, severity of inhibition was more pronounced with increase in concentration of the extract. Similarly, shading intensity of mango tree on two Hibiscus varieties WG-H Jamaica and WG-S were tested at a certain canopy distances (1/3rd, 1/2 and at tree periphery) from the bole of mango tree. Results reflect the increase in growth performance of both the varieties with increase in canopy distances from the bole of the tree probably due to better transmission of light. It is recommended that Hibiscus varieties should not be planted at the very closest distance from the mango trees stem due to allelopathic and shading effects, respectively. Key words: Allelopathic, bioassay, inhibition, leaf extract, Mangifera indica, shading effect.

Effect of Cichorium intybus on production performance, carcass quality and blood lipid profile of hybrid duck.

One hundred hybrid male ducks (Mojosari×Alabio) were used to examine the efficacy of chicory supplementation as nutritional feed manipulation on production performance, and blood lipid profile of hybrid ducks. The ducks were tagged, weighed, and then allotted randomly to one of the four treatment diets using a completely randomized design. The experimental diets were: 1) P0 (100% basal diets + 0% chicory as control), 2) P1 (95% basal diets + 5% chicory), 3) P2 (90% basal diets + 10% chicory) and 4) P3 (85% basal diets + 15% chicory). For each treatment group, there were 5 replicates of 5 birds each. All experimental diets were isonitrogenous and isocaloric using locally available ingredients. Hybrid ducks with fed diets supplemented fresh chicory (5, 10, and 15%) showed increased feed intake and body weight gain, as well as feed conversion ratio to be smaller than those ducks fed diets without chicory supplementation (control). The ducks fed 10% chicory supplementation contained significantly (p<0.05) lower ash and higher organic matter contents of meat than those ducks fed other diets. The ducks fed 15% chicory supplementation showed the lowest crude protein and cholesterol content of meat among the treatment diets. Ducks fed chicory supplementation showed lower (p<0.05) blood cholesterol and triglyceride levels than those ducks fed without chicory supplementation, while dietary interventions had no major (p>0.05) influence on low-density lipoprotein and high-density lipoprotein levels in duck blood. In this study, 10% chicory supplementation showed the best results characterized by an increase in growth performance, carcass quality, small intestinal histomorphology, and lower cholesterol levels of meat.

Evaluation of protected benzoic acid on growth performance, nutrient digestibility, and gut health indices in starter pigs.

Benzoic acid is a common alternative for antibiotic and zinc oxide use in nursery diets. Free benzoic acid (BZA) is often supplied, but this form is absorbed before it can exert any effect on distal segments of the gut. The study aimed to evaluate the effects of protected benzoic acid on growth performance, nutrient digestibility, plasma metabolites, and gut health indices in starter pigs. A total of 192 pigs were weaned at 28 ± 1 d age (initial body weight, 8.72 ± 1.13 kg). Pens were assigned to one of four treatment diets (n = 8 pens per treatment): (1) no additive (NC), (2) free benzoic acid (BZA; 0.6%), (3) protected benzoic acid (BC50; 0.2%, supplied at a ratio of one to three equivalents of BZA), and (4) antibiotic growth promoter (AGP; Carbadox, 50 ppm). Diets were fed for three weeks over two periods (period 1, 7 d; period 2, 14 d). Body weight and feed intake were measured for each period. Feces were collected at the end of each period to determine apparent total tract digestibility (ATTD) of organic matter (OM), gross energy (GE), and crude protein (CP). One pig per pen was euthanized per period to determine plasma metabolites; jejunum and ileum morphology; jejunum, ileum, and colon cytokine abundance; and jejunum, ileum, and colon tight junction protein expression. The AGP group had increased average daily gain (ADG) and average daily feed intake (ADFI) compared to other groups in period 1 and overall (P < 0.05); however, ADG and ADFI of the BC50 group was intermediate between the NC and BZA groups and the AGP group in period 2. The ATTD of OM, GE, and CP were greater in the AGP group compared to the NC and BC50 groups (P < 0.05), whereas the BZA group was intermediate. Jejunum and ileum villus height and crypt depth increased from period 1 to period 2 (P < 0.01) but were similar across groups. Ileum and colon tumor necrosis factor-α (TNF-α) abundances were greater, whereas colon interleukin (IL)-1β and colon and ileum IL-8 abundances were less, in the AGP group compared to the BZA group (P < 0.05); the NC and BC50 groups exhibited intermediate TNF-α, IL-1β, and IL-8 abundance in the ileum and colon. Jejunum cytokine abundance did not vary among groups but declined from period 1 to period 2 (P < 0.05). Tight junction protein expression also did not vary among groups. In summary, protected BZA supported a slight increase in growth performance in starter pigs, suggesting its potential as an alternative feed additive in nursery diets.

The Potential of beta-glucan as feed additives in broiler chickens: A review

Poultry as an industry was continuously growing worldwide and demands for poultry meats were markedly increasing. However, the limited use of antibiotics as treatments and as growth promoters became a serious problem due to the emergence of antibiotic resistance. Therefore, exploring other alternatives such as using feed additives like beta-glucans were widely studied and used to meet the demands of the consumers. This review focused on the different functions and effects of beta-glucans in poultry. Beta-glucans were known to have immunomodulation effects by upregulating the cytokines and other immune cells to overcome a disease. Aside from its immunomodulation effects, it can also increase the intestinal villi and crypts. Furthermore, an increase in growth performance was also observed. This evidence is promising but further research is required to properly establish the various functions of beta-glucans in poultry.

Effect of Coffee Silverskin Enriched Diet to Enhance the Immunological and Growth Parameters of Nile Tilapia (Oreochromis niloticus).

The application of low-cost feed additives as an immunostimulant for different species of fish is an emerging research area in aquaculture. The present study aimed at incorporating a byproduct from coffee processing, coffee silverskin, as an immunostimulant in Nile Tilapia. A total of 225 Tilapia fingerlings (each weighing 23.04±0.07) were fed on diets as follows: Diet 1 (control), Diet 2 (20 gm/kg), Diet 3 (40 gm/kg), Diet 4 (80 gm/kg) and Diet 5 (180 gm/kg) of coffee silverskin. The feeding experiment continued for four weeks; moreover, growth, as well as immunological studies, were carried out by collecting mucus and blood serum from the liver and intestine of the fish. A significant increase in growth performance was observed in fish fed with a 40 gm/kg coffee silverskin-containing diet. The same effect was found in immunological parameters, including complement activity, serum lysozyme activity, and respiratory burst activity. Therefore, it is concluded that the study was definitely a successful one, and a diet with 40 gm/kg of coffee silverskin (Diet 3) was effective, compared to the rest of the compositions.

Feed Supplementation with the GHRP-6 Peptide, a Ghrelin Analog, Improves Feed Intake, Growth Performance and Aerobic Metabolism in the Gilthead Sea Bream Sparus aurata

The aquaculture sector has experienced rapid and important growth with the subsequent increase of feeding and nutritional issues for sustaining this activity, mainly related to the use of high quality, safe and environmentally friendly feed ingredients. The use of additives in aquafeeds has proven to be a suitable option to improve different productive indicators in farmed fish. In the present study, the effect of adding the GHRP-6 peptide, a ghrelin analog, to a commercial diet of gilthead sea bream (Sparus aurata) was studied at two proportions (100 or 500 μg/kg of feed). Both experimental diets show an increase in growth performance, as well as in feed efficiency after 97 days of experiment. The lower inclusion of GHRP-6 (100 μg/kg) results in a better aerobic metabolism, while the higher inclusion significantly increased plasma GH levels in agreement with the GH secretagogue effects of ghrelin. Similar growth outcome and differences between GHRP-6 levels in aerobic metabolism and GH stimulation suggest that improvements in culture performance by this peptide may occur through different mechanisms. Taken together, this compound can be considered as a viable dietary supplement for increasing production efficiency of sea bream aquaculture, although a better understanding of its dose-specific effects is still required.

Effect of Leucas aspera Against Aeromonas hydrophila in Nile Tilapia (Oreochromis niloticus): Immunity and Gene Expression Evaluation

The present study addressed the effects of Leucas aspera enriched diet in Nile tilapia. Three hundred Nile tilapia were fed Leucas aspera as follows: 0 g kg-1 L. aspera (C-control), 5 g kg-1 L. aspera (T1), 10 g kg-1 L. aspera (T2) and 15 g kg-1 L. aspera (T3). After 30 days of feeding, significant (P&lt;0.05) increase in growth performance was noticed by feeding the fish the T2 diet. Thereafter fish were intraperitoneal injected with Aeromonas hydrophila in challenge test. After 21 days of challenge, highest survival rate (70%) was observed in fish fed the T3 diet followed by fish fed T2 diet (65%). Serum immunological parameters such as phagocytosis, alternative complement activity, respiratory burst activity and lysozyme activity were significantly (P&lt;0.05) enhanced in fish fed all inclusion levels of L. aspera with the maximum activity in fish fed the T2 diet. Hematological parameters were significantly (P&lt;0.05) higher in all groups fed L. aspera diets vs. control fed fish. No histopathological changes in liver were observed in fish fed the T2 diet in the histology study. Gene expression study revealed the upregulation in the expression of COX-2 and GR genes. In conclusion, the current results suggest that dietary administration of L. aspera especially the T2 diet, has beneficial effects in improving immunity and can mitigate the adverse effects of A. hydrophila infection in Nile tilapia.

Probiotic, Lactobacillus pentosus BD6 boost the growth and health status of white shrimp, Litopenaeus vannamei via oral administration

This study aims to assess and determine the oral-administration of probiotic, Lactobacillus pentosus BD6 on growth performance, immunity and disease resistance of white shrimp, Litopenaeus vannamei. Lac. pentosus BD6 effectively inhibited the growth of aquatic pathogens, which was used in the test. Shrimp were fed with the control diet (without probiotic supplement) for 60 days and the probiotic-containing diets at 107, 108, 109, and 1010 cfu kg−1, respectively. Shrimp fed with the diet containing probiotic at the doses of 109−10 cfu kg−1 showed significant increase in growth performance as well as feed efficiency than that of the control. After a challenge test with Vibrio alginolyticus, shrimp fed with a probiotic diet at a dose of 1010 cfu kg−1 showed a significantly lower mortality as compared to the control and that of shrimp fed the diet containing probiotic at the levels up to 107−8 cfu kg−1. In addition, a therapeutic potential of Lac. pentosus BD6 was discovered because the cumulative mortalities of shrimp fed with probiotic and pathogen V. parahaemolyticus simultaneously were significantly lower when compared to control shrimp. Probiotic in diet at a dose of 109−10 cfu kg−1 significantly increased PO activity of shrimp, while shrimp receiving probiotic at the doses of 108−10 cfu kg−1 showed significant increase in lysozyme activity and phagocytic activity. Shrimp fed with the diet containing probiotic at the level of 1010 cfu kg−1 also indicated higher gene expression of prophenoloxidase (proPO) I, but not proPO II, lipopolysaccharide and β-1,3-glucan-binding protein and penaeidin 4. Analysis of the bacterial microbiota of the shrimp intestine revealed that oral administration of probiotic increased the relative abundance of beneficial bacteria and reduced the abundance of harmful pathogenic bacteria in the gut flora of shrimp. Despite no statistically significant difference, an analysis of microbial diversity recorded higher species richness, Shannon–Weaver diversity index and evenness in the probiotic group, compared to the control group. It was concluded that Lac. pentosus BD6 has great antibacterial ability against a wide range of pathogens and has therapeutic potential to reduce the mortality of shrimp infected with V. parahaemolyticus. Additionally, dietary Lac. pentosus BD6 at the level of 1010 cfu kg−1 was recommended to improve growth performance, immunity and disease resistance of shrimp against V. alginolyticus.

Effect of a Multispecies Probiotic Mixture on the Growth and Incidence of Diarrhea, Immune Function, and Fecal Microbiota of Pre-weaning Dairy Calves.

The effects of different doses of a multispecies probiotic (MSP) mixture on growth performance, the incidence of diarrhea rate and immune function, and fecal microbial diversity and structure were evaluated in pre-weaning Holstein dairy calves at WK2, WK4, WK6, and WK8. Forty Chinese Holstein female newborn calves were randomly assigned to four treatments with 10 calves in each group, C (control group), T1 (0.5 g MSP/calf/day, T2 (1 g MSP/calf/day), and T3 (2 g MSP/calf/day) groups. The experimental period was 56 days. Feed intake and health scoring were recorded every day until the end of the experiment. Fecal contents and blood samples were sampled at WK2, WK4, WK6, and WK8. Growth performance, incidence of diarrhea, and total serum concentrations (IgA, IgG, and IgM) were analyzed. Bacterial 16S rRNA and fungal ITS genes were high-throughput sequenced for fecal microbiota. The relationships among the populations of the principal fecal microbiota at WK2 and the growth performance or serum immunoglobulin concentrations were analyzed using Pearson’s rank correlation coefficients. The MSP supplementation reduced the incidence of diarrhea in the first 4 weeks of life, and serum IgA, IgG, and IgM concentrations increased between WK2 and WK8 in the T3 group. There was an increase in growth performance and reduction in the incidence of diarrhea until WK4 after birth in T3 group, compared with the control, T1, and T2 groups. The results of fecal microbiota analysis showed that Firmicutes and Bacteroides were the predominant phyla, with Blautia, Ruminococcaceae_UCG-005, norank_f__Muribaculaceae, Bacteroides, Subdoligranulum, and Bifidobacterium being the dominant genera in calf feces. Aspergillus, Thermomyces, and Saccharomyces were the predominant fungal phyla. Compared with the control, in T1 and T2 groups, the MSP supplementation reduced the relative abundance of Bacteroidetes and increased the relative abundance of Bifidobacterium, Lactobacillus, Collinsella, and Saccharomyces at WK2 in group T3. Thus, the fecal microbial composition and diversity was significantly affected by the MSP mixture during the first 2 weeks of the calves’ life. MSP mixtures reduced the incidence of diarrhea in pre-weaning calves (during the first 4 weeks of life). There was a significant improvement in growth performance, reduction in calf diarrhea, balance in the fecal microbiota, and an overall improvement in serum immunity, compared with the control group. We, therefore, recommend adding 2 g/day of multispecies probiotic mixture supplementation in diets of dairy calves during their first 4 weeks of life before weaning.

Effects of dietary tea tree (Melaleuca alternifolia) oil and feeding patterns on the zootechnical performance and nonspecific immune response of the giant freshwater prawn (Macrobrachium rosenbergii)

AbstractThis study investigated the effects of dietary tea tree oil (TTO) supplementation and feeding patterns on the growth and nonspecific immunity of Macrobrachium rosenbergii. Prawns were randomly assigned into four patterns. Patterns 1 (P1) and 4 (P4): prawns were fed with a basal diet and basal diet supplemented with 100 mg/kg of TTO, respectively; Patterns 2 (P2) and 3 (P3): prawns were fed with the basal diet supplemented with 100 mg/kg of TTO at 1‐ and 2‐week intervals, respectively. A significant increase in growth performance was observed in the P3 and P4 compared with P1. The activities of antioxidant enzyme were significantly elevated in the P3 and P4 compared with the P1. The concentration of haemolymph malondialdehyde was significantly lower in the P3 and P4 than the P1. The haemolymph level of IL‐1 and TNF‐α was significantly lower in the P3 than the P4. The expression of toll and dorsal was significantly lower in the P3 than the P1. However, the expression of peroxiredoxin‐5 was significantly higher in the P3 than the P1. Overall, these findings indicated that feeding 100 mg/kg of TTO at 2‐week intervals significantly improved the growth performance and nonspecific immunity of M. rosenbergii.

Supplementation of probiotics in water beneficial growth performance, carcass traits, immune function, and antioxidant capacity in broiler chickens.

This study aims to investigate the effects of commercial probiotic supplementation in water on the performance parameters, carcass traits, immune function, and antioxidant capacity of broiler chicks. In the experiment, 120 Arbor Acres (AA) broilers (60 male and 60 female) were randomly allocated into four groups (G) – G1: basal diet and G2, G3, and G4: basal diet with 1% Lactobacillus casei, 1% L. acidophilus, and 1% Bifidobacterium in the water, lasting 42 days. The experimental results revealed that probiotic additives produced positive impacts on body weight, average daily feed intake (ADFI), and average daily weight gain for female chicks, whereas these probiotics significantly reduced ADFI and the feed conversion ratio of male chicks (P < 0.05). Probiotics efficiently improved eviscerated yield and breast yield while reducing the abdominal fat (P < 0.05) for the male broiler chicks. A marked increase was observed in the weight of the spleen, bursa of Fabricius, and thymus in the treatment group (P < 0.05). Besides, probiotics produced a significant effect on the concentrations of immune-related proteins (P < 0.05) and markedly increased the concentrations of antioxidase and digestive enzymes when compared with the control (P < 0.05). The addition of probiotics dramatically reduced the total counts of Escherichia coli and Salmonella and increased the quantity of Lactobacilli (P < 0.05). The results of the present study demonstrated an increase in growth performance, carcass traits, immune function, gut microbial population, and antioxidant capacity by supplementing 1% probiotics (L. casei, L. acidophilus, and Bifidobacterium) in the water for broilers.

Dietary supplementation of olive leaf extract enhances growth performance, digestive enzyme activity and growth related genes expression in common carp Cyprinus carpio

It is not desirable to use synthetic chemicals as growth promoters in aquaculture. Therefore, phytogenic compounds have been extensively studied in fish diets due to their growth promoter effects. Common carp (Cyprinus carpio) is widely distributed around the world and has been reared in Asia for several centuries. This study was conducted to determine the effects of olive leaf extract (OLE) (0, 0.1, 0.25, 0.50 and 1%) on the growth performance, digestive enzyme activity in the intestine and the expression levels of some growth-related genes in the brain. liver, head kidney and mucsle tissue of common carp C. carpio. At the end of the 60-day feeding period, there was a significant increase in growth performance in the OLE0.1 and OLE0.25 groups. Similar trends have been obtained for digestive enzyme activities such as α-amylase, protease and lipase. Morover, the expression of growth hormone (GH) and insulin-like growth factor I (IGF-I) was regulated by OLE supplemented by up to 0.25% in brain, liver, head kidney and muscle tissue. This study confirms that dietary OLE may enhance the growth performance of the common carp by activating the digestive enzyme activity in the intestine and increase the expression of genes (GH and IGF-I) related with growth in brain, liver, head kidneys and muscle tissue of common carp up to use 0.10% in diets.

Pepsinogen expression during larval development of a Persian Gulf Sparid, Sobaity

The present study aimed to detect the pepsinogen gene expression and pepsin enzyme activity, followed by ontogenetic development of gastrointestinal tube with emphasis on the functional stomach in Sobaity larvae (Sparidentex hasta) from hatching to 40 days post- hatching (DPH) reared at 21 °C. The exocrine pancreas including zymogens granules was detected coincident with the gradual yolk-sac absorption (1–3 DPH). The mouth and anus opened at 4 DPH simultaneously with the early convolution of the gut and its segmentation in anterior and posterior intestine, and the buccopharyngeal cavity. The most obvious differentiation in the digestive tract was the formation of an incipient stomach at 12 DPH, surrounded by striated muscle fibers and the development of the gastric glands. The functional stomach appeared 20 DPH onward, where it increased in size and the gastric folds elongated. The stomach was fully developed at 25 DPH with the transition from striated to smooth muscle cells and appearance of gastric glands in the posterior region of the stomach. Pepsinogen was not expressed before 12 DPH and significantly detected coincident with an increase in growth performance and also before the onset of weaning. It increased exponentially parallel to the larval stomach development and concomitant to the change in the diet from live to microbound food. The pepsin enzyme activity, even at a low level, was observed two days after pepsinogen gene expression (14 DPH), increasing sharply after the onset of weaning. Moreover, according to a phylogenetic tree based on the amino acid, the Sobaity’ sequence of pepsinogen was included in the subtype A2, when expressed during late larval development. These results enhanced our understanding of ontogenetic development of pepsinogen in this species, as the pepsinogen expressed earlier than when is expected, and suggest that farmers can initiate weaning at an earlier larval age than is currently practiced, regarding the fact that Sobaity larvae developed a functional stomach 25 DPH onwards.

Rearing of the Pacific white shrimp, Litopenaeus vannamei in a biofloc system: The effects of different food sources and salinity levels

The present study assessed the effects of different types of feeds and salinity levels on water quality, growth performance, survival rate and body composition of the Pacific white shrimp, Litopenaeus vannamei, juveniles in a biofloc system. Shrimp juveniles (2.56 ± 0.33 g) were cultured for 35 days in 300 L fibreglass tanks (water volume of 180 L) with a density of 1 g/L in six treatments. Three sources of feed (100% formulated feed, mixture of 66.6% formulated diet and 33.3% wet biofloc, and 100% wet biofloc) and two levels of salinity (10 and 32 ppt) were considered in two control groups and four biofloc treatments. Water quality parameters in the biofloc treatments were significantly better than control groups (p < .05). The highest increase in growth performance and survival rate were obtained in salinity of 32 ppt and mixed feed sources. Analysing the proximate composition of body shrimp indicates an increase in lipid and ash levels in biofloc treatments, which was more evident in the salinity of 32 ppt. In addition, the proximate analysis of shrimp body showed significant differences between biofloc treatments and control groups (p < .05). The highest FCR was found in the treatment with salinity level of 10 ppt and fed only with floc. Overall, it was found that the artificial diet supplemented with biofloc at the salinity of 32 showed better performance in the juvenile stage of Pacific white shrimp.

The Effects of Synbiotics and Probiotics Supplementation on Growth Performance of Red Hybrid Tilapia, Oreochromis mossambicus x Oreochromis niloticus

The purpose of this study was to evaluate the influence of a synbiotics between Lactobacillus plantarum and mannan-oligosaccharides (MOS) extract and probiotics (Lactobacillus plantarum) on growth performance in red hybrid tilapia (Oreochromis mossambicus x Oreochromis.niloticus). The fishes with initial average weight 11.9 ± 0.7g were randomly assigned to three dietary treatments which were fed on a diet containing probiotics only and a diet combination of probiotics and prebiotic (synbiotics), with four replicates for each treatment. The control group was fed without supplementation of any probiotics or prebiotics for the same duration. All the diets were isocaloric and isonitrogenous. All fish were fed daily at 3% of the body weight per day in two equal instalments. The feeding rate was kept at 4% body weight day-1 for the whole rearing period of 30 days, and the amount of feed was adjusted every tenth day following a bulk weighing of each group of fish. All diets contained about 32% of crude protein. Significantly (P &lt; 0.05) high growth performance (percent gain body weight, weight gain and feed intake) were observed in the group fed diet containing synbiotics as compared to probiotics and control group. Similarly, significantly (P &lt; 0.05) low FCR was recorded in synbiotics as compared to probiotics and control group. This result revealed that a feeding regime with synbiotics for 30 days led to a significant increase in growth performance, survival rate and feeding efficiency in red hybrid tilapia fingerlings.&#x0D;

Growth Performance, Biochemical Indices and Antioxidant Status of Grey Mullet (Mugil cephalus Linnaeus, 1758) Under Dietary L-Carnitine Supplementation

The present research evaluated the use of dietary carnitine supplementation and its effects on the growth, body composition, fatty acids, biochemical parameters, Insulin-like growth factor 1 (IGF-1) level and antioxidant activity, in grey mullet. Four experimental diets were prepared by adding carnitine at concentrations of 0, 400, 800, and 1200 mg kg−1 diet (C0, C400, C800 and C1200 respectively). After 9 weeks of the feeding trial, a significant increase in growth performance (except for Daily Growth Rate or DGR), carcass quality (crude protein and crude lipid), biochemical parameters (cholesterol, triglyceride, total lipid, free fatty acid or FFA, total protein, albumin, and globulin), plasma superoxide dismutase and glutathione peroxidase activities was detected in the fish fed on C800 diet, as compared to those fed on the other diets (P 0.05) differences were observed in moisture and crude ash contents among groups. Barring the C1200 diet, there was also a positive correlation between the plasma IGF-1 level and DGR. The results showed that the diet containing 800 mg kg−1 L-carnitine enhanced growth yield, feed utilization, and carcass quality; as well as biochemical and antioxidant activity of grey mullet. The authors concluded that the maximum recommended levels of L-carnitine in diets for grey mullet (Mugil cephalus) can be established at 800 mg kg−1.

A Comparison between dietary effects of Cuminum cyminum essential oil and Cuminum cyminum essential oil, loaded with iron nanoparticles, on growth performance, immunity and antioxidant indicators of white leg shrimp (Litopenaeus vannamei )

This study evaluates the effect of dietary cumin essential oil's (CEO) and cumin essential oil's loaded iron nanoparticles (CEO‐loaded NPs) on growth performance, haematological parameters and antioxidant status of white leg shrimp. Shrimps with the initial weight of 3.38 ± 0.014 g were allocated into 15 fibreglass tanks (300 L, 60 shrimps per tank) and were fed with five experimental diets containing 0 g/kg CEO (the control diet), 5 g/kg CEO, 10 g/kg CEO, 5 g/kg CEO‐NPs and 10 g/kg CEO‐NPs for 56 days. After 56 days of culture, the shrimps fed with CEO and CEO‐loaded NPs supplemented diets showed a more significant increase in growth performance (p < .05) than in the control diet. Total haemocyte count (THC) value, large‐granule cells (LGC), hyaline cells (HC)%, superoxide dismutase (SOD) and Alkaline phosphatase (AKP) activity were significantly higher (p < .05) in the shrimps fed with CEO and CEO‐loaded NPs supplemented diets than the shrimps fed with the control diet. Glutathione peroxidase (GPX) enzyme activities along with the glucose and cholesterol concentrations significantly decreased in the shrimps fed with the CEO and CEO‐loaded NPs supplemented diets more than those fed with the control diet. The results suggest that the dietary CEO‐loaded NPs can improve the growth performance, the health status and the antioxidant capacity of L. vannamei.