Protective effects of prebiotic in zebrafish, Danio rerio, under experimental exposure to Chlorpyrifos

The current study estimated the immunotoxicological effects of the herbicide chlorpyrifos at sub-lethal concentration and the potential ameliorative effects of galactooligosaccharide (GOS) in Danio rerio. Fish was sampled after a 56-days feeding with GOS and then exposed to 15 mg/l chlorpyrifos for 7-days to assess the non-specific immune responses (total protein, immunoglobulin and ALP activity). The results revealed that feeding zebrafish with 1% dietary GOS increased total protein levels (P<0.05), but no significant effect was noticed between groups fed 0.5 and 2% GOS and control (P>0.05). There were significant difference between total immunoglobulin levels 1% and control group (P<0.05). Furthermore, in case of ALP activity no significant alteration was noticed between GOS fed fish and control (P>0.05). The present findings revealed that dietary supplementation with GOS could be useful for modulation of the immunity in response to chlorpyrifos exposure, thereby presenting a promising feed additive in aquaculture

Effects of different levels of live food replacement with microdiet on growth factors, survival and resistance to salinity stress of Indian white shrimp post-larvae (Fenneropenaeus indicus)

In this study, partial and complete replacement of live food (Artemia nauplii) with a microdiet was investigated in post-larval Indian white shrimp, Fenneropenaeus indicus. Post-larvae (PL1) were stocked into nine 20-L vessels (5-L water volume) at a density of 50 L-1. Shrimp were fed six times a day over 10 days. At the end of the feeding period, there was no significant difference in quality index (stress-test survival) among treatments. Statistical analysis of results showed that partial or complete replacement of live food with microdiet significantly decreased survival, total length, carapace length, weight, growth rate, performance index, and the number of spines in upper rostrum of the post-larvae. However, substitution of live food with microdiet had no negative effects on resistance to salinity stress. These results showed that the commercial microdiet used in this study is not a good replacement of live food; further studies are required to determine the nutritional requirements of Indian white shrimp larvae and post-larvae before microdiets can be utilized effectively

Effects of apple cider vinegar on growth performance and non-specific immune parameters of skin mucus in common carp (Cyprinus carpio) fingerlings

This study was undertaken to evaluate the effects of apple cider vinegar on growth performance and non-specific immune parameters of skin mucus (alkaline phosphatase, lysozyme and total protein) in common carp fingerlings. For this purpose, a total of 240 fish were stocked in twelve tanks for four treatment with three replications and fed by diets supplemented with 0, 1, 2 and 4 % apple cider vinegar for 60 days. The result showed that there was no significant difference in body weight increase (BWI), feed conversion ratio (FCR), specific growth rate (SGR) and condition factor (CF) among the treatments (P>0.05). The results revealed that there is no significant difference among skin mucus alkaline phosphatase of fish in all treatments. Although skin mucus lysozyme activity and total protein significantly increased by apple cider vinegar in comparison with the control group. The highest and lowest skin mucus lysozyme activity and total protein in common carp fingerlings were observed at 2% apple cider vinegar and control group, respectively. Therefore, apple cider vinegar improves skin mucus lysozyme activity and total protein and can be a good candidate for antibiotic replacement in common carp fingerlings

The effect of water temperature on food transit time and digestive enzymes activity in Caspian kutum (Rutilus kutum) larvae

The present study investigates the effects of water temperature on digestive enzymes activity and food transit time in Caspian kutum (Rutilus kutum) larvae. Caspian kutum larvae (532 ± 0.05 and 543 ± 0.02 mg) were divided into two groups with three replicates and reared at different water temperature i.e. 25.6 ± 0.4°C (T1) and 18.4 ± 0.1°C (T2). At the end of the experiment, sampling of intestine was performed at 0, 1, 3, 5, 8, 16, 24 and 30 h after feeding from each treatment. In T2, food was observed until 24 h after feeding and the intestine was empty 29 h after feeding, while in T1 19 h after feeding the intestine was empty. Digestive enzymes activities were higher in T2 treatment. The peaks of trypsin and alkaline phosphatase enzymes activity were found 8 h after feeding in T1, while occurred 16 h after feeding in T2. The highest chymotrypsin and alpha-amylase enzymes activity were observed 5 and 8h after feeding in T1 and T2, respectively. These results confirmed remarkable effects of temperature on food transit time and digestive enzymes activity of Caspian kutum

UČINCI DIJETETSKOG KOMERCIJALNOG KVASCA GLUKANA NA IMUNOLOŠKI ODGOVOR, HEMATOLOŠKE PARAMETRE, CRIJEVNU MIKROFLORU I PERFORMANCE RASTA MLAĐI BIJELE BODORKE (Rutilus kutum)

This study investigates the effects of different levels of commercial yeast glucan (CYG) on innate immune response, hematological parameters, intestinal microbiota, growth performance and survival rate of white fish (kutum) fry. Specimens (1.1 ± 0.15 g) were randomly allocated into 15 tanks (100 L) at a density of 25 fish per tank and triplicate groups were fed either a basal control diet (0% CYG) or a basal diet supplemented with yeast (0.5, 1, 1.5 or 2% CYG) for 60 days. All dietary CYG levels significantly increased the innate immune responses (IgM levels and lysozyme activity) (P 0.05), but WBC levels were significantly higher in CYG fed fish (P < 0.05). Microbiological assessment indicated that the viable culturable autochthonous and lactic acid bacteria (LAB) levels significantly elevated in 0.5 and 1% treatments. Our results indicated that low levels of dietary CYG (0.5 and 1 %) improved growth performance, body protein levels and survival rate compared to the control treatment (P < 0.05). These results indicate that CYG stimulates innate immune response, improves growth performance and modulates intestinal microbiota of kutum fry. Thus, we suggest that low level CYG may be used as a beneficial dietary supplement in kutum fry culture.Ova studija istražuje utjecaj različitih razina komercijalnog kvasca glukana (CYG) na imunološki odgovor, hematološke parametre, crijevnu mikrofloru, brzinu rasta i stopu preživljavanja kod mlađi bijele bodorke. Uzorci mlađi (1,1 ± 0,15 g) su slučajnim izborom podijeljeni u 15 spremnika (100 L) pri gustoći od 25 riba po spremniku, a hranjeni su u triplikatu skupina sa osnovnom kontrolnom ishranom (0% CYG) ili osnovnom ishranom nadopunjenom kvascem (0,5, 1, 1,5, ili 2% CYG) 60 dana. U svim CYG prehrambenim razinama značajno se povećao imunološki odgovor (razine IgM i lizozim aktivnost) (P 0,05), ali WBC razina bila je znatno viša u riba koje su hranjene s CYG (P <0,05). Mikrobiološka procjena ukazuje da su razine živih kultura autohtonih i mliječno kiselih bakterija (LAB) značajno povišene u 0,5 i 1% tretmanu. Rezultati pokazuju da niska razina ishrane s CYG (0,5 i 1%) uzrokuje bolju performansu rasta, razinu tjelesnih proteina i stopu preživljavanja u usporedbi s kontrolnom (P <0,05). Ovi rezultati pokazuju da CYG stimulira imunološki odgovor, poboljšava performanse rasta i modulira crijevnu mikrofloru kod mlađi bijele bodorke. Dakle, predlažemo da se niska razina CYG može se koristiti kao koristan dodatak prehrani u proizvodnji mlađi bijele bodorke

Effects of florfenicol on skin mucus immune parameters and immune related genes expression in zebrafish (Danio rerio)

Florfenicol (FF) is a common, inexpensive antibiotic with relatively low toxicity. The present study investigates the possible effects of Florfenicol on cutaneous mucus immune parameters and immune related genes expression in Danio rerio. After two weeks adaptation, fish were stocked in experimental units at density of 20 fish per aquaria and fed with experimental diets containing 0, 10, 30 and 50 mg/kg FF per for 11 days. Evaluation of immune parameters at the end of trial showed that the control group had a significantly lower level of lysozyme activity when compared with those treated with antibiotic. However, the skin mucus total immunoglobulins level of fish fed diets containing antibiotics did not show any significant difference compared to the control group. The highest expression level of TNF-α, IL1β and lysozyme was observed in fish treated with 10 mg/kg FF while the lowest expression was noticed in those fish treated with 30 and 50 mg/kg FF. The present results indicate the relatively positive effects of this antibiotic on the immune system of zebrafish, and it seems that the appropriate dosage of the drug can serve as an immunostimulant for zebrafish

Preliminary study on semi-closed incubator efficiency for hatching Persian sturgeon (Acipenser persicus) eggs

The present study investigated the efficiency of semi-closed incubator for hatching the Persian Sturgeon (Acipenser persicus) eggs. The incubator was basically designed according to Vase equipped with collector vessel, recirculation pump and aerator. 50% of water was changed every day. Persian Sturgeon (50 g) fertilized eggs samples were stocked in the incubators with three replica. Water flow rate was set not to harm the eggs and only circulating the eggs. The mortality of embryos and larvae at gasterula stage, formation of S-type heart stage, before hatching and hatching percent were recorded. Our result showed that the incubated circulated eggs completely and the probability of fungal infections was lower than that of flow through incubators. Since water used in semi-closed incubator is far less than that of flow through systems, that semi-closed incubator may be a proper alternative for flow-through incubated systems in future

The study of enrichment capability of adult Artemia franciscana with singular or combined administration of Pediococcus acidilactici and fructooligosaccharide

The present study investigates the possibility of enriching adult Artemia franciscana with singular or combined administration of Pediococcus acidilactici and fructooligosaccharide (FOS). The experiment was conducted in a completely randomized design with four treatments, including synbiotic, P. acidilactici +FOS (T1), probiotic, P. acidilactici (T2), prebiotic, FOS (T3) and control (T4). To evaluate the enrichment of adult Artemia with each treatment, sampling was performed at 2, 4 and 6 hrs post enrichment. The bacterial counts was measured using the microbial culture and expressed as log CFU per g Artemia. A pre-experiment has been designed and probiotic was used in three levels (107, 108 and 109 CFU per litter of suspension) and prebiotic was used in three levels of 1, 2 and 5 g per litter of suspension. Based on pre experiment results, 108 CFU per litter of probiotic and 5 g per litter of prebiotic was selected. The results of this experiment showed that over time, consumed bacteria increased by adult Artemia and there was a significant difference between sampling in terms of ingested bacteria. The highest bacterial count (6.78±0.03 log CFU g-1) was observed 6 hrs after the start of enrichment. Based on microbial culture, the number of bacteria P. acidilactici in T1 and T2 was significantly higher than those in T4 (control) and T3 (prebiotic). There was no significance difference between T2 (probiotic) and T1 (synbiotic). In conclusion, the results of this study showed that adult Artemia in a short time (about 4 hrs) can retain a large amount of probiotic bacteria

The effects of dietary Myrtle (Myrtus communis L.) supplementations on growth performance and some innate immune responses in rainbow trout (Oncorhynchus mykiss)

This study investigated the effect of dietary Myrtle (Myrtus communis L.) powder on the growth performance, immune responses and haematological parameters of rainbow trout fingerlings. Twelve cages were assigned to four treatments in triplicate and thirty fish (6.50±0.55g (were stocked. Treatments were different levels 0 (control), 0.5 (M0.5), 1 (M1) and 1.5% (M1.5) of Myrtle powder. The highest weight gain and specific growth rate and lowest feed conversion ratio were observed in fish fed with 1% Myrtle. The RBC, WBC and haematocrit were higher in the Myrtle fed treatments compared to the control group. The results showed increased total protein in M1.5 and M1 treatments compared with the control and M0.5 treatment. Also, the highest and lowest albumin were observed in M1.5 treatment and control group. Furthermore, serum ALP decreased along with the increasing Myrtle levels in diet, and lowest level was observed in M1 treatment. Lysozyme activity increased with increasing dietary Myrtle inclusion levels, although no significant difference was noticed when compared with control. These results revealed the potential growth enhancing and health promoting effects of Myrtle powder