Effect of probiotic Pediococcus acidilactici on growth, reproductive and bacterial count of marine rotifer Brachionus plicatilis

This study investigated the effects of different concentrations of probiotic Pediococcus acidilactici on the total number, specific growth rate, attached egg number and microbial count (lactic acid and total aerobic bacteria) in culture water and body of marine rotifer Brachionus plicatilis. The experiment was conducted as a completely randomized design in four groups: first group fed probiotic at 0.5í—106 CFU ml-1 (P1), the second group fed probiotic at 1í—106 CFU ml-1 (P2), the third group fed probiotic at 1.5í—106 CFU ml-1 (P3), and the last group fed without probiotic (NP, control). Rotifers were cultured in standard conditions at an initial density of 30 ind.ml-1 using a 2.5í—106 cell mL-1 of Nanochloropsis oculta. Based on the results, the maximum number (215±4.91 ind.ml-1) of rotifers were significantly obtained after ten days in the third group in comparison to other treatments (P<0.05). In addition, the highest growth rate (0.46±0.023 ind.ml-1) and shortest doubling time (1.5±0.14 days) were obtained in the treatment P3 but no significant difference was found between NP and other groups (P>0.05). Moreover, it was revealed that the total aerobic bacteria was significantly related to the 3rd group that found be 1.80í—103 CFU rotifer-1 and 34.0í—104 CFU ml-1 in rotifer body and culture water,respectively (P<0.05). Nonetheless, lactic acid bacteria of rotifer body and culture water was not concentration-dependent and the highest number of lactic acid bacteria in rotifer body (50.58±6.08 CFU rotifer-1) and rotifer culture water (4.43±3.28í—103 CFU ml-1) was obtained in the treatments of P1 and P2, respectively. In conclusion, the present study showed that the bacteria P. acidilactici with N. oculta algae provide a higher growth rate and total aerobic bacteria in rotifer B. plicatilis

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

Short-term enrichment of microalgae with inorganic selenium and zinc and their effects on the mineral composition of microalgae and marine rotifer Brachionus plicatilis

Rotifers are widely used as a live prey for finfish larvae, although their content in minerals such as selenium and zinc is lower than in fish. In the present study, mixed microalgae (i.e., Isochrysis aff. galbana and Nannochloropsis oculata) were enriched with different amounts of Se and Zn either alone (45, 90, and 135 mg L−1 of Zn, 60, 120, and 180 mg L−1 of Se) or mixed (22.5, 45, and 90 mg Zn L−1 and 30, 60, and 120 mg Se L−1). The content of minerals in the microalgae was analysed after 1 and 3 h enrichment and their effect on the growth and mineral composition of the rotifer. Based on the results, 1 h enrichment time and 90 and 120 mg L−1 of Zn and Se, respectively, resulted in the highest amount of Se and Zn in enriched microalgae. The maximum Zn content was detected in the rotifers fed 90 mg L−1 Zn and 90 mg L−1 Zn +120 mg L−1 of Se, but the maximum Se was observed in rotifers fed with 120 and 180 mg L−1 Se. Thus, Se- and Zn-enriched rotifers can be used as a mineral delivery method to cover marine fish larvae nutritional requirements.info:eu-repo/semantics/acceptedVersio

Improving co‐feeding strategies for Neotropical green terror cichlid (Aequidens rivulatus) larvae with lecithin‐enriched Artemia franciscana nauplii: Effects on survival, growth performance and body composition

The effects of feeding on a commercial diet and lecithin‐enriched (EN) Artemia franciscana nauplii for improving co‐feeding strategies of Neotropical green terror cichlid (Aequidens rivulatus) larvae were conducted. For this purpose, eight groups of fish in triplicates were assigned with two different diets (unenriched Artemia [UN] and EN Artemia) and four feeding regimes (1, 5, 10 and 25 days feeding with UN and EN diets and then a 10% daily replacement Artemia nauplii with commercial diet). The crude lipid (21.4%) and total polar lipid (12.96% of total crud lipid) levels significantly increased in enriched Artemia nauplii (p < 0.05). The highest amount of saturated fatty acids (SFA) were in enriched and UN Artemia nauplii (41.74% and 49.64% respectively) but the highest level of monounsaturated fatty acids (MUFA) (25.69%) and polyunsaturated fatty acids (PUFA) (49.11%) were obtained in commercial diet. Growth performance of fish fed 10 EN and 5 EN had significantly higher values of total weight (120.67, 120.31 mg), %WG (584.48, 580.50%) and SGR (7.69, 7.67%) respectively (p < 0.05). Nevertheless, fish fed 25 EN had significantly higher FCE (190.4%), PER (3.95) and NPU (202.5), in comparison with other groups. In terms of body composition, the EN Artemia nauplii led to increased lipid contents in 25 EN, 10 EN and 5 EN treatments. In conclusion, the results of this study revealed that feeding regimes of 10 EN and 5 EN could improves survival and growth performance of Neotropical green terror cichlid, A. rivulatus larvae.info:eu-repo/semantics/acceptedVersio

Long-term effect of zinc oxide nanoparticles on population growth, reproductive characteristics and zinc accumulation of marine rotifer, Brachionus plicatilis

In the present study, the effects of ZnO nanoparticles (NPs) on marine rotifer, Brachionus plicatilis, was investigated in three separate experiments. Firstly, the sensitivity and reproductive characteristics of B. plicatilis were studied at concentrations of 0, 0.1, 0.5, 1, 3, 5 and 10 mg L-1 of ZnO-NPs for 10 days. Based on the results, the total number of rotifers (TNR) significantly decreased at 5 and 10 mg L-1 of ZnO-NPs. In addition, the specific growth rate (SGR) of animals was negative at two of the concentrations of ZnO-NPs. In the second experiment, the TNR at 4 concentrations of ZnO-NPs (0, 10, 13, 17, and 19 mg L-1) during 72 h were tested and the 24-72 h LC50 of ZnO-NPs was calculated. After three days, the entire population of rotifers was generally lost at 19 mg L-1 of ZnO NPs. The LC50 of ZnO-NPs in animals at 24, 48, and 72 h intervals was registered as 18.2±1.34, 12.43±0.08, and 9.63±0.26 mg L-1, respectively. Finally, the zinc accumulation in rotifers was measured at different concentrations (0, 0.1, 0.5, and 1.3 mg L-1) of ZnO-NPs and maximum zinc (123 μg g-1 of rotifer DW) uptake by rotifers was observed in treatment 3 mg L-1 of ZnO-NPs. In sum, it can be concluded that the B. plicatilis can be used as a biological model for studying marine water contaminants with nanoparticles, especially ZnO-NPs

The effects of zinc-enriched Saccharomyces cerevisiae on the growth and mineral composition of marine rotifer, Brachionus plicatilis

Rotifers are important zooplankton in commercial finfish hatcheries. However, due to the limited variety of food available, zinc content of cultured rotifers in artificial environments may not meet the requirements of fish larval. It has been reported that direct addition of soluble zinc to culture media was not effective on the zinc content of rotifer. Thus, in this study, the effect of zinc-enriched Saccharomyces cerevisiae was investigated on the growth and mineral composition of rotifer, Brachionus plicatilis. Four different food treatments, including (1) yeast without enrichment (control), (2) yeast containing 21.23 mg g-1 of zinc, (3) yeast containing 56.25 mg g-1 of zinc, and (4) yeast containing 132.93 mg g-1 of zinc, were used to produce rotifer for a period of 10 days. Afterwards, specific growth rate (SGR), the total number of rotifers, total eggs attached to rotifers, and the total number of eggs were measured. Finally, the mineral composition of rotifer in different treatments was analyzed. The findings revealed that yeast enriched with 56.25 mg g-1 of zinc significantly improved the growth of rotifers. The maximum number of rotifers (274 ind ml-1), total eggs attached to rotifers (29.3 number ml-1), and the total number of eggs (36 number ml-1) were found in the third treatment. The highest zinc content was observed in the fourth treatment (about 822.5 μg g-1 of rotifers). The maximum values of Fe (13.84 μg g-1 of rotifers) and Mn (15.22 μg g-1 of rotifer) were related to the treatment 4 and control, respectively. However, the amount of Cu did not significantly differ among the treatments. In conclusion, this study found that zinc-enriched yeast improved the growth, reproduction, and body composition of B. plicatilis

The effect of different concentrations of organic and inorganic zinc on the growth and zinc content in yeast (Saccharomyces cerevisiae)

Introduction: In the aquaculture industry, yeasts like other microorganisms such as algae, play a major role. Yeasts can absorb minerals from their culture and is able to transfer nutritional materials to other organisms. Materials and methods: In this study, the effect of three concentrations (2.5, 5 and 7.5 g L-1) of organic (zinc-threonine) and inorganic (zinc-sulfate) zinc in culture media on the growth and enrichment of Saccharomyces cerevisiae was investigated. One group was also selected as the control treatment (each with 3 repetitions). Yeast culture was performed under standard conditions in YEPD medium and in 1-liter flasks. The amount of yeast added in the culture media was 10 g L-1. Results: Based on results, the most growth inhibitory of yeast was observed after adding 2.5 g L-1 of zinc threonine, and with increase in zinc amount in culture media, the growth rate increased but still significantly lower than zinc sulfate and control treatments. In the zinc sulfate groups, the growth inhibitory of yeast was observed after adding 7.5 g L-1 of zinc sulfate, but other treatments did not show significant difference with the control treatment. In this study, the highest zinc content (115.67 ± 4.65 mg g-1) in yeast was observed in the treatment 7.5 g L-1of zinc sulfate, which was significantly higher than other treatments (

Effects of zinc oxide nanoparticles on photosynthetic pigments, zinc accumulation, and activity of antioxidant enzymes of Dunalilla salina

Zinc oxide nanoparticles (ZnO-NP) are widely used in various industries. Their release into the aquatic environment has caused concerns about their potential consequences on aquatic organisms and ultimately human health. In the food chain, algae as primary organisms play an important role in absorbing water-soluble particles and transporting them to high nutritional levels. In this study, we investigated the effect of different concentrations (0, 0.1, 1, and 10 mg/L; T0, T0.1, T1 and T10 respectively) of ZnO-NP on photosynthetic factors, zinc accumulation, and antioxidant enzymes of Dunaliella salina. By the increased concentration of ZnO-NP in the algae medium, the amount of zinc accumulation in the algae upraised, so that, the highest amount of zinc was significantly observed in T10 mg/L (

Effects of probiotic Lactobacillus acidophilus and Candida utilis on mucus immunity indices, liver enzymes, and growth of common carp, Cyprinius carpio

The purpose of this study was to evaluate the effects of Lactobacillus acidophilus and Candida utilis probiotics on mucus immunity, growth indices and liver enzymes of common carp (Cyprinus carpio). This study was in the form of a completely randomized design with 4 treatments and 3 repetitions including: 1- basic diet, 2- basic diet + bacteria (1.23 g), 3- basic diet + yeast (0.67 g) and 4- basic ration + bacteria (0.625 g) and yeast (0.333 g) per kg of diet in 60 days. A number of 300 fish with an average weight of 12 ± 0.33 g were randomly distributed in 12 tanks (300 L) with a density of 25 fish in each tank. Based on the results, no significant difference was observed in terms of growth indices between the treatments except for the protein efficiency ratio (p>0.05). However, significant differences were found between the treatments (p<0.05) in terms of mucus immune parameters, lysozyme activity, total immunoglobulin and total protein. It was also true for AST and ALP which exhibited significant differences between the treatments (p<0.05). Based on the general results of this study, using Lactobacillus acidophilus and Candida utilis as probiotics displayed the highest enhancement on the fish immune system

Lecithin-enriched Artemia combined with inert diet and its effects on reproduction and digestive enzymes of Aequidens rivulatus

The present study investigated the effects of soybean lecithin bioencapsulated in adult Artemia franciscana and unenriched Artemia in combination with an inert diet on digestive enzymes activity and reproductive performance in Aequidens rivulatus (green terror cichlid). Eight hundred and ten fish (3.1 ± 0.2 g) were randomly allotted into glass tank (80 L) and assigned to ten dietary treatments with 5 different levels (0, 25, 50, 75, and 100%) of either lecithin-enriched Artemia (EA) or unenriched Artemia (UA) over a period of 90 days. The amount of total polar lipid increased from 39.2% in the unenriched Artemia to 43.7% in the lecithin-enriched Artemia (P < .05). The fish fed with 50% EA had higher total weight, and total length compared with other groups (P < .05). The peculiar functions of total alkaline proteases, α-amylase, and lipase in green terror increased in the groups fed with lecithin-enriched Artemia, compared to the un-enriched groups (P < .05). The highest total alkaline proteases activity was observed in the fish fed with 75% EA treatment. In comparison to the other groups, fish fed 100 and 0% levels of Artemia replacement had significantly highest and lowest α-amylase activity values, respectively. Concerning reproductive performance, the highest average fecundity, egg diameter, egg weight, fertilization, hatching, and larval survival rates, as well as the lowest time between two spawning episodes, were obtained in fish fed 50% EA. In conclusion, this feeding strategy is advisable for a proper nutritional management of broodfish of green terror cichlid.info:eu-repo/semantics/acceptedVersio