BACKGROUND: Vitamins are considered an essential part in diet of aquatic animals. OBJECTIVES: This study was carried out to assay the effect of different levels of vitamin E on growth performance, carcass compositions and blood parameters of common carp fingerlings (Cyprinus carpio). METHODS: Total number of 96 common carp fingerlings weighing 15.49 ± 3.64 g were randomly distributed into 12 fiberglass tanks in four treatments group including control (without added vitamin), 100, 200 and 400 mg/kg vitamin E in three replicates and kept at a density of 8 fish per tank for 10 weeks. RESULTS: Results showed that the highest weight gain, percentage of body weight increase, mean daily growth, specific growth rate, condition factor and the lowest food conversation ratio were observed in fish fed with 200mg/kg vitamin E but no significant differences were seen compared to other treatments (p>0.05). Fish fed with 200mg/kg vitamin E had the highest (p>0.05) contents of protein and ash compared to control group. There was an increase in values of RBC, Hct and Hb in fish fed with 100, 200 and 400 mg/kg vitamin E in comparison with control group. Significant differences were observed in MCHC in fish fed with 100 mg/kg vitamin E compared to control and fish fed with 400 mg/kg, also treatment 200 mg/kg with treatment 400 mg/kg vitamin E (p<0.05). Fish fed vitamin E in 200 and 100 mg/kg had the highest WBC count. Fish fed with different levels of vitamin E had higher lymphocyte in comparison with control group and fish fed with 100 mg/kg had significant difference with control in lymphocyte (p<0.05). CONCLUSIONS: Vitamin E in level of 200 mg/kg can play an important role to enhance growth performance, nutrition efficiency and improving blood indices and support cell immunity in common carp fingerlings.

BACKGROUND: Recently chitosan nanoparticles have been applied as an immunostimulant and adjuvant in biomedical fields. OBJECTIVES: In this study the adjuvant effects of nanochitosan, derived from shrimp shell's chithin, on immunogenicity of Aeromonas hydrophila vaccine in common carp were evaluated. METHODS: Totally 300 juvenile common carp (51±5.6 g, Mean ±SD) were randomly divided into four groups each contained three subgroups with 25 fishes. Groups 1, 2 and 3 were immunized intraperitoneally with A. hydrophila vaccine. No adjuvant used in group 1, but nanochitosan and freund adjuvant were used with vaccine in groups 2 and 3 respectively. Group 4 (Control) injected with normal saline instead of vaccine. Fish were immunised at days zero and 14 and fishes were reared in the same situation for 6 weeks. Serum samples were taken every other weeks and immunological parameters including WBC, serum lysozyme and bactericidal activity, serum complement activity, NBT reduction activity, total protein and globulin levels and anti A.hydrophila antibody titer were compared among the groups. At the end of experiment all groups were challenged with LD50 concentration of A. hydrophila and mortality recorded for ten days. RESULTS: WBC, serum lysozyme and complement activity, NBT activity, globulin level and anti A.hydrophila antibody titer were increased in nanochitosan and freund groups compare to control group (P<0.05). Serum bactericidal activity and serum albumin level showed no significant change among the groups (P>0.05). Challenge mortality decreased in immunised groups compare to control. CONCLUSIONS: Nonochitosan posses proper adjuvant effects which is comparable with freund adjuvant and can be a good candidate as an alternative to current adjuvant in fish vaccines.

BACKGROUND: In recent years, medicinal plants have becomean important option for use in aquaculture industry. Objectives: This study was conducted to determine meanlethal concentration (LC50) and investigated the anesthetic effectof Topped lavender essential oil (Lavandula angustifolia) on common carp(Cyprinus carpio) juveniles. Methods:Mean lethal concentration of essential oil was calculated based on the OECD(Organization Economic Cooperation and Development) standard in static system.For determining  LC50, 150common carp juveniles with mean body weight of 26.96 ± 1.98 g were used in 6groups and one control group and each group with three replications (7juveniles were used for each replication). After Compatibility period (about 2weeks), juveniles were exposed to different concentrations including 71.12,72.11, 73.11, 74.13, 75.16 mg/l that were calculated by logarithmic formula.Juvenile behavioral changes and mortality were recorded in the time period at24, 48, 72 and 96 hours after exposed to Topped lavender essential oil.Determination of Topped lavender essential oil anesthetic effect was done in 6groups (with 3 replicates), as 10 fish exposed to increasing concentrationsincluding 0 (control), 160, 165, 170, 175 and 180 mg/l. Results: Mean lethal concentration(LC50) after 96 hours was obtained 99.70 mg/l. The lowest time for completionof anesthesia (stage 3 anesthesia) was obtained at a concentration of 170 mg/lwith 3.74± 0.35 min and the full recovery of this concentration was obtained at3.91±0.55 min. The results showed that the best anaesthetic concentration ofTopped lavender essential oil was 170 mg/l. Conclusions: It seems that Topped lavender essential oilcould be used as anesthetic agent

This experiment has been performed to assess the effect of partial substitution of fishmealwith lentil seeds in common carp growth performance, feed utilization and certain biologicalparameters (Fulton condition, Hepatic somatic index, Gills somatic index, Kidney somatic index,Spleen somatic index, Intestine Length index, Intestine weight index). Fish from a private fishfarm were acquired in province of Sulaimaniyah, Iraq. Average fish weight ranged from 95-99gm. Fish were divided into 5 treatment groups. The treatments were: T1: In fish diet 0% lentilseed was replaced with fishmeal, T2: In fish diet 5% lentil seed was replaced with fishmeal, T3:10% lentil seed was replaced with fishmeal, T4: 15% lentil seed was replaced with fishmeal, T5:20% lentil seed was replaced with fishmeal. There had been significant differences in weightgain, daily, relative, and specific growth rate as lentil seed replaced with fishmeal in fish diet.Feed Efficiency Ratio, Protein Efficiency Ratio and Fat Efficiency Ratio was significantly higherin T5 group than that of the other treated groups. No significant differences in the mean values ofHepatosomatic index, Spleensomatic index and Kidneysomatic index were detected. Significantdifference in the mean value of Condition Factor was found among treatment groups. Intestinelengthindex was significant among treatment groups according to fish weight while mean value showed non-significant cording to fish length. The performance and general health of thecommon carp were significantly improved by raw lentil seed. Due to their low price incomparison to fishmeal and commercially available in all markets, it is suggested to substitutethe fishmeal with raw lentil seed in commercial fish diet.

Objective—To evaluate the long-term protective immunity of a cyprinid herpesvirus 3 (CyHV3) vaccine in naïve koi (Cyprinus carpio koi). Animals—72 koi. Procedures—Vaccinated koi (n = 36) and unvaccinated control koi (36) were challenge exposed to a wild-type CyHV3 strain (KHVp8 F98-50) 13 months after vaccination. Results—The CyHV3 vaccine provided substantial protective immunity against challenge exposure. The proportional mortality rate was less in vaccinated koi (13/36 [36%]) than in unvaccinated koi (36/36 [100%]). For koi that died during the experiment, mean survival time was significantly greater in vaccinated than in unvaccinated fish (17 vs 10 days). Conclusions and Clinical Relevance—The CyHV3 vaccine provided substantial protective immunity against challenge exposure with CyHV3 13 months after vaccination. This provided evidence that koi can be vaccinated annually with the CyHV3 vaccine to significantly reduce mortality and morbidity rates associated with CyHV3 infection.

OBJECTIVE To determine the pharmacokinetics of danofloxacin following IM administration of a single dose (10 mg/kg) in koi (Cyprinus carpio). ANIMALS 69 healthy adult koi housed in a 980-L flow-through-system tank. PROCEDURES 3 fish were kept as untreated controls, and the remaining 66 fish were assigned to 11 treatment groups with 6 fish/group. Fish in the treatment groups were given a single dose of danofloxacin (10 mg/kg) IM in the left epaxial musculature. Fifteen, 30, and 45 minutes and 1, 4, 12, 24, 72, 96, 120, and 144 hours after administration of danofloxacin, fish in each treatment group were euthanized, and blood samples and samples of liver, spleen, gill, anterior kidney, posterior kidney, skin and muscle, and scales were collected. Plasma and tissue drug concentrations were determined by liquid chromatography–tandem mass spectrometry, and noncompartmental pharmacokinetic analyses were performed. Tissues from the untreated control fish and fish euthanized 144 hours after danofloxacin administration were examined histologically. RESULTS Maximum plasma concentration (mean, 8,315.7 ng/mL) was reached approximately 45 minutes after danofloxacin administration; plasma elimination half-life was 15 hours. Danofloxacin was detected in all examined tissues from all 6 fish euthanized 15 minutes after drug administration and was detected in some tissues from 3 of the 6 fish euthanized 144 hours after drug administration. For all tissues, results of histologic examination were unremarkable. CONCLUSIONS AND CLINICAL RELEVANCE IM administration of a single dose (10 mg/kg) of danofloxacin in koi resulted in rapid absorption, with maximum plasma concentration reached approximately 45 minutes after drug administration; the drug could still be detected in some tissues 144 hours after administration.

OBJECTIVE To determine in vivo effects of nitric oxide (NO) on blood-brain barrier (BBB) permeability in common carp (Cyprinus carpio L.). ANIMALS 148 carp. PROCEDURES Carp received glyceryl trinitrate (1 mg/kg) as an NO donor or received no treatment (control group). Nitrite and nitrate concentrations in carp sera were determined 0.25, 1, 3, 6, 8, 12, and 24 hours after treatment. In control and treatment groups, BBB permeability was analyzed by assessment of leakage of Evans blue dye into various brain areas at 6, 12, and 24 hours after glyceryl trinitrate treatment. Brain edema was determined by means of the wet-dry weight method and assessed with light microscopy on H&E-stained preparations of tissues obtained 6 and 24 hours after glyceryl trinitrate treatment. RESULTS Treatment with glyceryl trinitrate induced endogenous synthesis of NO, which was upregulated 6 and 8 hours after treatment. Increased NO synthesis was associated with increased permeability of the BBB, which developed 6 hours after treatment with the NO donor. Although the BBB became impermeable again by 12 hours after glycerol trinitrate treatment, brain edema still persisted 24 hours after treatment. CONCLUSIONS AND CLINICAL RELEVANCE In this study, treatment with an NO donor caused reversible opening of the BBB and brain edema in common carp. An intact BBB is important to prevent influx of potentially harmful substances into the brain. This investigation highlighted the possibility of BBB disarrangement caused by NO, a substance found in the CNS of all vertebrates evaluated.