Sustainable Aquaculture and Health Management Journal
Volume:7 Issue: 2, Summer and Autumn 2021

Heart failure (HF) incidence increases worldwide and is affected by various risk factors such as coronary artery disease, hypertension, obesity, and diabetes. Dietary recommendations for patients with HF have generally focused on sodium restriction; however, different nutritional approaches are considered in patients with a high risk of malnutrition due to the diuretic drugs they use. Omega-3 fatty acids obtained from aquatic organisms are essential regulators of cardiovascular health. There are different opinions on giving/consuming omega-3 fatty acids (and supplements) to improve the symptoms of heart failure. Although found mainly in oily fish, EPA and DHA, the marine n-3 polyunsaturated fatty acids are now found in commercially available supplements over the counter (as fish oils) or as concentrated pharmaceutical preparations. Fatty fish is the premier natural food source of EPA and DHA. In this study, we review the effects of omega-3 fatty acids, associated with low cardiovascular disease risk, on HF while trying to understand if it could ameliorate or exacerbate HF.

The herbicides used in agriculture threaten aquatic ecosystems and biodiversity on a global scale. There are several reports on the residues of currently used herbicides in the tissues of aquatic organisms. This study aimed to determine the effect of concentration on the accumulation of Butachlor in liver tissue in zebrafish fish exposed to sub-lethal concentrations of the toxin. In this study, we investigated the losses and residual toxins in the water and the liver of the zebrafish exposed to sub-lethal concentrations of Butachlor herbicide. This study was performed on 680 zebrafish. Initially, to determine the LC50-96 h value, a preliminary pilot study was performed, according to which, the main experiment was then conducted considering four treatments each with three replicates for 30 days. The experimental groups included T1 (exposure to 40% of the LC50-96 h concentration of Butachlor), T2 (exposure to 60% of LC50-96 h), T3 (exposure to 80% of LC50-96 h), and control (C). Mortality was recorded daily. Sampling was conducted from water and liver tissues on the first day and the days 15 and 30 to determine Butachlor residues using gas chromatography (GC). The results showed that Butachlor residue in water was associated with the concentration of the toxin and the exposure time, (T3>T2>T1 groups; p <0.05). According to the results, the highest mortality and residual Butachlor in the liver tissue were related to the T2>T3>T1> C groups on days 15 and 30 after exposure (p <0.05) respectively. According to the results of this study, Butachlor herbicide can accumulate in liver tissues of zebrafish even when it is used in low concentrations. Also the behavioral and clinical features following Butachlor use included restlessness, rapid respiration, air swallowing at the surface of the water, loss of balance, and disoriented swimming was observed. Regarding the importance of fish as the protein source in humans’ food, this phenomenon can be a potential threat to human health. Therefore, it is necessary to reduce the application of this toxin and replace it with alternative compounds.

During this research  from April to August 2020, some 30  fish of Chalcalburnus chalcoides were caught from different parts of Sefidrood by cast nets. The fish were anesthetized using 25 mg/l of clove flower extract. In order to identify the parasites, blood, eyes, various internal organs were sampled. All of the isolated parasites were stained and clarified using Hematoxylin and Eosin stain and valid parasitology keys. Examination of internal parts of Chalcalburnus chalcoides revealed varying degrees of infestation by different parasitic species, including fish eyes infection by trematodes Diplostomum spathaceum, (infestation percentage 53.3%). Meanwhile, blood was affected mainly by Trypanosome percae (13.3%), Cryptobia sp. (10%), abdominal cavity by Eustrongylides excisus (20%), Clinostomum complanatum (13.3%), anisakis larvae (23.3%), Asymphylodora kubanicum (46.6%), Caryophylaelus laticeps (13%), Khavaia arminica (76.6%), metacercaria plerocercoid Ligula intestinalis (13.3%), Bothriocephalus gowkongensis (20%), Raphidascaris acus (26%) and Corynosoma caspicum (30%). Almost all of the examined fish were found to have been infested by at least one or two parasite species. The new finding of this research is that isolation and identification of four parasites species namely as zoonosis Clinostomum complanatum, Eustrongylides excisus, Ligula intestinalis and Anisakis larvae are reported in this fish species for the first time.

This study has investigated the impacts of biofloc on water quality, growth parameters, and whole-body composition of the Litopenaeus vannamei juveniles (initial average weight 5.23±0.20 g). Five experimental treatments were designed: Shrimp fed basal diet (Control), 5 and 10% wet biofloc-supplemented diets (W5 and W10), 5 and 10% dried biofloc-supplemented diets (D5 and D10) for 32 days. Experimental tanks (50 liters) as triplicate for each treatment, was stocked 12 shrimps. During the experiment, chemical and physical water parameters were examined and were not different statistically among experimental treatments. At the end of the experiment, in W10 treatment, the growth parameters were significantly higher than the control treatment. Also, in W10 and D5 treatments, feed conversion efficiency (FCE) and feed conversion ratio (FCR) were significantly better than the control. Compared to other treatments, significantly better protein efficiency ratio (PER) and lipid efficiency ratio (LER) were observed in W10 treatment. Results indicated that in W10 and D5 treatments, the protein, ash, and dry matter contents of the shrimp were significantly higher compared to the control treatment. Also, in W10, D5, and D10 treatments, carcass lipid and fiber contents were significantly higher compared to the control. Overall, the best performance was observed in shrimp fed on 10% wet biofloc-supplemented diet.

This study aimed to investigate the effects of complementary rainbow trout diets with different concentrations of Celmanax® (active compounds of Saccharomyces cerevisiae with mannan-oligosaccharide (MOS)) on immune responses, pressure resistance and resistance to Yersiniosis. Rainbow trout were fed with a diet containing various concentration levels of S.cerevisiae with MOS (prebiotic) (0, 0.1, 0.5 and 1%) for 60 days. While evaluating some of the parameters of the immune system, the blood samples were prepared from the tuber stem vein every 30 days. On day sixty of the study, various stress tests including temperature increases, hypoxia and induction of experimental disease with Yersinia ruckeri were also performed in all the experimental groups. Results showed that lysozyme activity, alternative complement pathway and total antibody were significantly elevated by diets containing different concentrations of prebiotic and the effective supplementation diet concentration was found to be 0.1% (p<0.05). However, the results of environmental pressures and exposure to bacteria showed that rainbow trout resistance was increased with different concentrations of prebiotic and the effective supplementation diet concentration was also 0.1% (p<0.05). Based on these findings, it is suggested that to increase and enhance immunity and improve rainbow trout resistance, it would be appropriate to add 0.1% concentration of prebiotic in the diet.

This study was conducted to evaluate the effect of different doses of GnRH on stress response in female koi carp (Cyprinus carpio). For this purpose, forty sexually mature female koi carp with an average weight of 102.05 ± 9.03 g were divided to four groups and fish received with a single intraperitoneal 0.9% NaCl with 20 mg kg-1 metoclopramide (C); 10 μg kg body weight-1 (BW) GnRH with 20 mg kg-1 metoclopramide (Gn10); 20 μg kg BW-1 GnRH with 20 mg kg-1 metoclopramide (Gn20); 50 μg kg BW-1 GnRH with 20 mg kg-1 metoclopramide (Gn50). Blood samples were collected before and after ovulation (approximately 24 h post-injection). The concentrations of plasma cortisol, lactate, and glucose were measured. Broodstocks who received GnRH spawned, while broodstocks of the group C did not spawn. The Gn10, Gn20, and Gn50 treatments led to significantly higher cortisol, lactate, and glucose concentration after ovulation compared to before injection (p< 0.05). The present results showed that females are highly sensitive to manipulation during reproduction and higher levels of the hormone cause more stress broodstocks, so they must be held with minimal disorders, especially during spawning period.