bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth Performance and Nutrient Utilization of African Mud Catfish (Clarias gariepinus) Fingerlings fed Different Levels of Fermented Pigeon Pea (Cajanus cajan) meal
Authors: Abdulraheem I. , Moronkeji T. , Olude O.O. , Obasa S.O. , Alegbeleye W.O.
Published: February 2021

The suitability of fermented pigeon pea meal as a protein ingredient in diets for Clarias gariepinus fingerlings was evaluated. A strain of Rhizopus oligoporus was used to ferment the meal for six days at 37°C. Five isonitrogenous (30% crude protein) and isoenergetic (16.45 MJ/kg) diets were formulated in which fermented meal was used to replace soybean meal at five inclusion levels (0%, 25%, 50%, 75%, 100%). Diets were fed to triplicate groups of C. gariepinus fingerlings for 70 days. Crude protein content (22.6%-27.0%), total sugar, calcium, and phosphorus increased while lipids, carbohydrate, crude fiber, and antinutritional factors decreased in catfish fed increasing levels of pigeon pea meal. The group fed the 100% diet had significantly (p<0.05) better growth, which declined as the inclusion level declined. The apparent digestibility coefficients protein and dry increased with the inclusion level. No histopathological changes were observed in the liver. The highest crude protein content in catfish tissues was obtained in the group that received the highest inclusion level. The study shows that fermented pigeon pea meal can replace soybean meal in practical feeds for C. gariepinus without compromising growth performance or nutrient utilization.
Induction of Sexual Maturation in Wild Female European Eels (Anguilla anguilla) in Darkness and Light
Authors: Tasselli A. , Modugno S. , Sirri R. , Di Biase A. , Mordenti M.
Published: February 2021

Sexual maturity was induced in wild silver eel females of the European eel (Anguilla anguilla) using a protocol similar to that successfully used for Anguilla japonica. Eels were injected for sixteen weeks with increasing doses of carp pituitary extract (10, 20, 30, and 40 mg CPE/kg body wt) and kept in natural light or completely dark conditions. In both groups, final oocyte maturation and ovulation were induced by injection of 17,20 h-dihydroxy-4-pregnen-3-one (DHP) at 2 mg/g body wt. All sixty eels turned out to be silver and actively migrant (58 in stage V and two in stage IV), showing a particularly high eye index (15.75±1.40), and distributed within three age classes (7-9 years). In the group kept in darkness, one of the four females ovulated 12 h after DHP injection in the thirteenth week. The remaining three females received the final (16th) CPE injection and ovulated 12-36 h after the DHP injection. In the group kept in light, two of the four females received the 16th CPE injection and ovulated 12-36 h after the DHP injection; the remaining two did not ovulate within 36 h post DHP injection. The total number of eggs released by the group kept in darkness (1,485,600) was significantly higher than that of the group kept in light (274,000). There was no mortality during the experiment.
Use of Organically Certified Yeast in the Diet of Juvenile Rainbow Trout (Oncorhynchus mykiss): Growth Performance, Nutrient Utilization, and Fatty Acid Composition
Authors: Davies S. , Tekinay A. , Guroy D.
Published: February 2021

This study evaluated the effects of the dietary organically-certified yeast, NuPro™, used as a replacement for fishmeal, on growth performance, nutrient utilization, and fatty acid composition in juvenile rainbow trout, Oncorhynchus mykiss. Two reference diets (conventional and organic) and three experimental diets (including 10%, 20%, or 30% NuPro™) were formulated. Diets were assigned to triplicate groups of 20 fish (4.0 g) for 12 weeks. There were no differences in growth performance or feed conversion ratio (FCR) between the two reference groups and growth responses were similar among experimental groups (p>0.05). Fish fed the 20% diet grew significantly better than the conventional group (p<0.05). Similarly, there were no significant differences in nutrient utilization between reference groups or between experimental groups, and none in body composition between any group (p>0.05). The highest n-3/n-6 ratio was obtained in fish fed the organic diet and the lowest in fish fed the 30% diet. Results show that organically certified yeast can contribute be an effective alternative to plant proteins in organic trout feed.
Using Microsatellites to Assess Genetic Variation in a Selective Breeding Program of Chinese Bay Scallop (Argopecten irradians irradians)
Authors: Li. Li , Zhang S. , Zhang G.
Published: February 2021

This study aimed to improve our understanding of the genetics of the Chinese bay scallop (Argopecten irradians irradians), one of the most important maricultured shellfish in China. Ten polymorphic microsatellite loci were examined to assess the allelic diversity, heterozygosity, and genetic variation between two domesticated populations selected for fast growth in breeding programs, and their base population. Forty-one alleles were found throughout the loci and the mean number of alleles per locus ranged 3.30-3.50. The average heterozygosity ranged 0.38-0.45, whereas the polyamorphic information content ranged 0.1504-0.7518. Genetic differences between the three populations were detected based on the number of alleles per locus, effective number of alleles, Shannon index, inbreeding coefficient (Fis), p values, genetic distance, and pairwise Fst values. There was no significant loss of genetic variability in the breeding program but changes in gene frequencies were detectable over the populations, implying that thea loci were saffected by the pressures of selective culture.
Using Microsatellites to Assess Genetic Variation in a Selective Breeding Program of Chinese Bay Scallop (Argopecten irradians irradians)
Authors: Zhang G. , Li. Li , Zhang S.
Published: February 2021

This study aimed to improve our understanding of the genetics of the Chinese bay scallop (Argopecten irradians irradians), one of the most important maricultured shellfish in China. Ten polymorphic microsatellite loci were examined to assess the allelic diversity, heterozygosity, and genetic variation between two domesticated populations selected for fast growth in breeding programs, and their base population. Forty-one alleles were found throughout the loci and the mean number of alleles per locus ranged 3.30-3.50. The average heterozygosity ranged 0.38-0.45, whereas the polyamorphic information content ranged 0.1504-0.7518. Genetic differences between the three populations were detected based on the number of alleles per locus, effective number of alleles, Shannon index, inbreeding coefficient (Fis), p values, genetic distance, and pairwise Fst values. There was no significant loss of genetic variability in the breeding program but changes in gene frequencies were detectable over the populations, implying that thea loci were saffected by the pressures of selective culture.
Use of Red and Blue Light-Emitting Diodes (LED) and Fluorescent Lamps to Grow Microalgae in a Photobioreactor
Authors: Kommareddy Anil , Anderson Gary A. , Koc Caner
Published: February 2021

High oil content microalgae are a source for biofuel production. They can be produced in open ponds or closed photobioreactors. To efficiently grow such microalgae, illumination for photosynthesis, CO2 consumption, and the pH and nutrient content of the growth medium must be monitored and precisely controlled. In a closed photobioreactor, illumination is the most critical parameter because it is the most expensive factor of algae production and must be operated 24 h per day. In this research, Chlorella kessleri (UTEX 398) microalgae were grown in photobioreactors. All parameters were identical, except the source and intensity of the illumination. The light sources included red light-emitting diodes (LED), blue LED, and fluorescent lights. Growth of the microalgae was observed for seven days and the effects of the three illumination sources on cell count, cell weight, and cell size were determined. In the first experiment, in which the current of all three light sources was the same, red LED produced the highest number of cells with the highest weight while blue LED light produced the largest cells. In the second experiment, in which the light intensity was the same for all three light sources, the highest weight was again achieved with the red LED. Thus, we suggest that most advantageous production system may be to use a red light initially to produce the desired cell concentration, then switch to a blue light to increase cell size.
Effects of Intensive and Semi-Intensive Rearing on Growth, Survival, and V-Shaped (Lordotic) Skeletal Deformities in Juvenile Gilthead Sea Bream (Sparus aurata)
Authors: Can Erkan
Published: February 2021

Intensive production can reduce production costs and improve efficiency of larvae culture. This study compared the effects of intensive and semi-intensive production on growth, survival, and V-shaped skeletal deformities in juvenile gilthead sea bream (Sparus aurata). At the end of the 50-day study, survival was 68.01±0.8%, mean weight was 1.32±0.03 g, and lordosis was 32% among juveniles raised in the intensive system. Survival and mean weight were significantly higher, 92.06±1.1% and 1.61±0.02 g, respectively, among juveniles raised in the semi-intensive system, and none had lordosis (p<0.05). Results suggest that semi-intensive systems are more advantageous than intensive for rearing sea bream juveniles.
Improved Resistance to Vibrio parahaemolyticus in Black Tiger Shrimp Penaeus monodon Treated with Streptococcus phocae PI80 and Bacillus subtilis
Authors: Arul V. , Paari A. , Yuvaraj N. , kumar R. Satish , Kanmani P. , Pattukumar V.
Published: February 2021

The aim of the study was to establish the immune response induced by Streptococcus phocae PI80, Bacillus subtilis, and commercial probiotics (Uni-Ecosense, EcoForce, Uni-Hatch) in the shrimp, Penaeus monodon. Total hemocyte count, phenoloxidase activity, nitroblue tetrazolium (NBT) reductase assay, phagocytic activity, and disease resistance was evaluated for 30 days. Total hemocyte count, phenoloxidase activity, NBT reductase assay, and phagocytic activity significantly increased in juveniles and adults treated with S. phocae PI80, a mixture of S. phocae PI80 and B. subtilis, or a commercial probiotic, but there were no significant differences in live weight of shrimps treated with probiotics or the control. Treatment with S. phocae PI80 plus B. subtilis enhanced survival of shrimps challenged with Vibrio parahaemolyticus. Our study demonstrates that administration of S. phocae PI80+B. subtilis at 4.6 х 108 CFU/ml water induced immune modulation, enhanced immune ability, and increased resistance to V. parahaemolyticus in juvenile and adult black tiger shrimp.
Enhancement of Growth Performance and Pigmentation in Red Oreochromis mossambicus Associated with Dietary Intake of Astaxanthin, Paprika, or Capsicum
Authors: Yilmaz Sevdan , Ergün Sebahattin , Soytas Nergiz
Published: February 2021

Diets for tilapia, Oreochromis mossambicus, were supplemented with astaxanthin, paprika, or capsicum to determine their effects on growth performance and pigmentation. Seven isonitrogenous (37% crude protein) and isoenergetic (18 kJ/g) diets were formulated to contain 40 or 60 mg carotenoid per kg diet. Triplicate groups of 210 fish were stocked in 21-l plastic boxes and fed one of the three experimental diets or the control diet for 45 days. Significantly better final weight, weight gain, specific growth rate, and food conversion ratio were obtained with the diets containing 40 or 60 mg/kg paprika than with control diet (p<0.05). In general, the carotenoid-supplemented diets significantly increased the values of redness (a), yellowness (b), and chroma (C), and decreased the values of lightness (L) and hue (Hoab) on the tail, body, and head areas (p<0.05). Results show that paprika or capsicum oleoresin can be used as an alternative natural carotenoid source in O. mossambicus diets to ensure good pigmentation, better growth, and feed utilization.
Diseases of Mariculture Finfish Species: A Review
Authors: Naveenchandru V. , Sudhagar S. Arun , Nilavan S. Ezhil , Saravanan K.
Published: February 2021

Mariculture has been steadily growing over the last few decades. To satisfy the increasing demand of local and export markets for fish and to control overexploitation of marine fish species, many countries are expanding mariculture activities. Disease is one of the most limiting factors in mariculture. Intensification of mariculture favors pathogens, which increase disease outbreaks. Diseases are broadly classified into infectious and noninfectious diseases. Infectious diseases are further divided into four groups based on the nature of the pathogen: viral, bacterial, parasitic, or fungal. Noninfectious diseases are divided into neoplastic diseases, genetic and environmentally induced diseases, and nutritional deficiency diseases. This paper provides detailed information regarding prevalent diseases of maricultured finfish species.
Hematological Changes in Common Carp (Cyprinus carpio) and Rainbow Trout (Oncorhynchus mykiss), Infected with Saprolegnia spp.
Authors: Gupta Monika , Pandey N.N. , Singh Raghvendra
Published: February 2021

The present study was conducted to investigate the physiological impairment in common carp (Cyprinus carpio) and rainbow trout (Oncorhynchus mykiss) infected with Saprolegnia spp. The following hematological parameters were studied: total erythrocyte count (TEC), total leukocyte count (TLC), hemoglobin (Hb), packed cell volume (PCV), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC). Except TLC, which significantly increased in the infected fish, all parameters decreased in response to infection. Decreases in Hb, TEC, and Hct were significant, indicating that saprolegniosis causes anemia and immunosuppression.
Effect of Dietary Carbohydrate Levels on the Growth and Liver Function of Carp Cyprinus carpio
Authors: Qiao X. , Bai D. , Cheng Z. , Cui P. , Sun J.
Published: February 2021

This experiment was conducted to study the effects of carbohydrate levels on the growth and liver function of Tianjin carp, Cyprinus carpio (mean body weight, 60.82 ± 0.38 g). Three diets, including 30% protein and 5.5% fat (dry matter) and 0, 15, or 30% corn starch (carbohydrate source) were provided to control, low carbohydrate, or high carbohydrate treatment groups, respectively. Weight gain, specific growth rate, hepatopancreas somatic index, and liver glycogen content were significantly higher in fish fed the 30% corn starch diet than fish fed 0% corn starch (P<0.05) but did not differ between the other two treatment groups. Protein efficiency ratio increased significantly as corn starch level increased (P<0.05), but feed conversion ratio showed the opposite trend (P<0.05). Glutamic pyruvic transaminase activity in the serum significantly increased with increasing corn starch levels (P<0.05), but total protein (decreasing trend) and glutamic-oxaloacetic transaminase (increasing trend) did not differ among dietary treatments. Histomorphological analysis of hepatopancreas sections showed that fish fed 15% or 30% corn starch diets presented mild hydropic degeneration and fatty degeneration or severe fatty degeneration, respectively. In summary, although carbohydrates promote carp growth, they enhance glycogen and fat accumulation in the hepatopancreas, reducing its function.
Histopathology and Detection of Cyprinid Herpesvirus Infection in Two Koi Farms in Tianjin City (China)
Authors: Song Y. , Huo Y. , Chen C. , Sun J. , Lü A. , Hu X. , Liu X.
Published: February 2021

Koi herpesvirus (KHV) is the etiologic agent of koi herpesvirus disease (KHVD) causing mass mortalities in common carp (Cyprinus carpio carpio), koi (Cyprinus carpio koi), and ghost carp (Cyprinus carpio goi) populations. In this study, we report new outbreaks of the koi herpesvirus (KHV) disease in a koi carp farm in Tianjin city, northern China. From June to September 2017, severe mortalities of koi juvenile and broodstock occurred in ornamental fish, and infected koi carp which showed signs of lethargy and loss of appetite, and clinical signs including sunken eyes, gill necrosis, and excessive secretion of mucus. Histopathologically, the gills showed hyperplasia and degeneration of epithelial cells and fusion of the lamellae, and foci necrosis was found in gills, liver, kidney, and spleen. In addition, KHV and Carp edema virus (CEV) were detected in the diseased koi fish by diagnostic PCR tests for the viruses. The results showed that the nucleotide sequences of thymidine kinase (TK), DNA polymerase (SphI-5), and four open reading frame (ORF 25, ORF 56, ORF 72, ORF 81) genes confirmed the highest identity with other KHV strains such as KHV-I, KHV-U and KHV-J, but the CEV was negative. The phylogenetic tree showed KHV-TJ1708 and KHV-TJ1709 clustered with the Asian strain KHV-J (AP008984). Results of the present study confirmed the prevalence of Carp herpes disease (KHVD) in China koi populations by means of clinical examination, histopathology and molecular technique. These data will provide a reference for diagnosis, quarantine, and surveillance of KHV in China.
Combined Effects of Dietary Phosphorus Level and Polyculture on Fish Production, Water Quality, and Plankton Composition, in Intensive Culture of Crucian Carp
Authors: Tang H. , Sun Y. , Liao H. , Chen M. , Li B.
Published: February 2021

The combined effects of dietary phosphorus (P) levels and co-culture of silver and bighead carp on fish production, water quality, and the planktonic community in intensive culture of crucian carp (Carassius carassius) were studied in this enclosure experiment. There were four treatments with three replicates each: crucian carp (50 fish) fed with low (8.7 g/ kg) or high phosphorous (13.5 g/ kg) diets (L1 and H1), and polyculture (50 crucian carp + 10 silver carp + 10 bighead carp) fed with low or high-phosphorus diets (L3 and H3). Results suggested that polyculture with filter feeders suppresses crucian carp growth, especially when supplied with low phosphorus diet. Polyculture significantly enhanced the total fish production when crucian carp were fed a diet with high P levels. Dietary P level and polyculture with silver and bighead carp did not affect dissolved oxygen (DO), pH, water transparency, NH4+-N, total nitrogen, or any form of phosphorus (p < 0.05), while the presence of filter feeders significantly suppressed plankton. The present experiment suggested that silver carp is more suitable for polyculture with crucian carp, and a higher P level is needed to support plankton and reduce competition with crucian carp.
Antifungal Activity of Magnolia officinalis Derived Magnolol and Honokiol on Membrane Disruption of Saprolegnia parasitica
Authors: Yang S. , Defang C. , Ouyang P. , Geng Y. , Deng Y. , Wang K. , Huang X. , Shi C. , Duan J. , Feng Y.
Published: February 2021

Saprolegniosis is an infectious disease caused by Saprolegnia sp. It may cause serious losses in fish farms and hatcheries in many countries. In previous research, Magnolia officinalis has been found to initiate the death of Saprolegnia sp. Magnolol and honokiol, two active substances in M. officinalis, may be responsible for the antifungal effects on Saprolegnia sp. The present study centered on the anti-fungal activity and mechanism of magnolol and honokiol on Saprolegnia parasitica. Results revealed that magnolol and honokiol displayed effective anti-fungal activity on S. parasitica, which caused their mass mortality. More intuitive research has shown that magnolol and honokiol have evolved mechanisms that can destroy the cell membranes of S. parasitica, and cause exosmosis of their cytoplasmic saccharides and proteins, and cause mortality. Magnolol and honokiol exhibited minimum inhibitory concentration values of 976.6 ug/mL and 587.4 ug/mL concentrations, respectively, and the minimum inhibitory time of both was 2 hours. This study provides a clearer understanding of the function of M. officinalis against Saprolegnia sp.
Optimum Replacement Value of Fish Silage for Protein Source in Pacific White Shrimp Diets
Authors: Visto R.V. , Tumbokon B.L.M. , Caigoy J.C.C. , Serrano A.E.
Published: February 2021

Chemical and biological evaluations were undertaken to determine nutritive value of acid fish silage (FS) as a dietary protein source in the diet of Pacific white shrimp (Litopenaeus vannamei). Proximate composition, and amino acid profile of FS were determined for chemical evaluation; amino acid profile of FS was employed to predict its nutritive value against shrimp requirements for essential amino acids (EAA). Three biological evaluations of FS were conducted: (1) the attractability of the FS diets were compared with diets containing no FS; (2) a growth trial of 60 days was performed to determine the effects of replacing protein sources in the diet with FS, on the growth performance of the shrimp; (3) shrimp from the growth trial in the second biological experiment were evaluated to determine whether or not FS in the diet resulted in enhanced immune response against Vibrio parahemolyticus. Experimental diets were prepared containing 5 levels of FS replacing the combined fish meal and Acetes meal (kept at a constant ratio of 1:3): 0% FS (control), 12.5%, 25%, 37.5% and 50% FS replacement. For results of the chemical evaluation, the computed EAAI of FS was 98.5 indicating a well-balanced profile. In the attractability test using a custom-made setup, results showed that shrimp (1-2 g) were significantly more attracted to the diet containing 50% FS replacement than any other diet; the control and the other experimental diets were statistically similar in attractability. In the growth trial experiment, shrimp (average weight =0.01g) were fed diets of the same composition as that used for the attractability test. Results showed that weight gain (WG) and specific growth rate (SGR) of the FS-supplemented groups were significantly higher than the control group; however, 25% FS group did not significantly differ from that of the 37.5% FS. Feed conversion ratio (FCR), protein efficiency ratio (PER) and survival rate did not differ significantly among experimental groups. In the V. parahemolyticus challenge test, optimum FS replacement for immune enhancement was estimated to be 24.5% FS using a broken line model. In conclusion, the findings revealed that FS could serve as a feeding stimulant at 50% FS replacement. Likewise, FS could serve as an immunostimulant against V. parahaemolyticus in L. vannamei.
Molecular Cloning, mRNA Expression, and Nutritional Regulation of a Fatty Acyl Δ6-Desaturase-like Gene of the Manchurian Trout, Brachymystax lenok (Pallas)
Authors: Ying H , Zong-fu H , Jie C , Hua-xin N , Shu-guo L , Jian-hua Y
Published: February 2021

The fatty acyl delta-6 desaturase (Δ6-desaturase) is a key rate-limiting

enzyme in the biosynthesis of long-chain polyunsaturated fatty acids (LCPUFAs).

To study the effects of different oil sources in the feed on the

nutritional regulation of Δ6-desaturase-like gene mRNA expression, the fulllength

cDNA of the Δ6-desaturase-like gene was cloned from the liver of

Manchurian trout (Brachymystax lenok). A 9-week feeding trial was

performed, and the fish received diets with three different oil sources: fish oil

(FO), sunflower oil (SO), and linseed oil (LO). The results showed that the

2448 bp long full-length cDNA contained an open reading frame (with a length

of 1365 bp), encoding 454 amino acids. Gene expression analysis indicated

that Δ6-desaturase-like gene mRNA is widely distributed throughout different

tissues, with highest expression levels in both the liver and the brain. The

linolenic acid (ALA) and linoleic acid (LA) compositions were highest in LO and

SO diets, respectively. The eicosapentaenoic acid and docosahexaenoioc acid

composition in LO and SO diets were significantly lower than in the FO diet.

Fish fed with SO and LO showed significantly higher liver expression levels of

Δ6-desaturase-like gene mRNA than those fed with FO. This indicates that SO

and LO in the diet affected the nutritional regulation of the Δ6-desaturase-like

gene mRNA in the liver of the Manchurian trout. In addition, these data

suggest that the Manchurian trout has the ability to synthesize long-chain

unsaturated fatty acids (LC-PUFAs) from ALA and LA.
Differences in Total Carotenoid Content in Tissues of the Pearl Oyster Pinctada fucata with Regard to Cuticle Shell Color
Authors: Wang Y , Ma Z , Li Y , Deng Z , Chen M , Wei H
Published: February 2021

The aim of this study was to compare total carotenoid content (TCC) in tissues, and its correlation with shell color between four different shell color strains of Pinctada fucata. A total of 120 individuals (30 golden shells, 30 red shells, 30 black shell and 30 white shells) of P. fucata of similar size were evaluated. In this study, stomach, gill, adductor, and mantle were used for measuring the determination of TCC. The color measurements were taken from both the nacre shells and cuticle shells. The results showed that TCC varies significantly among four different tissues and the four different shell color strains (P < 0.05). A significant difference between the cuticle shell colors of the four different shell color strains of P. fucata was observed (P < 0.05), while the nacre shell colors of four shell strains were similar (P > 0.05). In the present study, results indicated that the TCC of P. fucata was significantly related to tissue and cuticle shell colors (P < 0.001), but not related to nacre shell colors (P > 0.05). TCC relating to the cuticle shell color suggested that increasing or decreasing TCC in P. fucata through selective breeding of cuticle shell color was feasible, and it could be significant both for food for humans, and the cultivation of high-quality pearls.
Discontinuous Administration of β-glucan is Effective for Preventing Immune Fatigue in Litopenaeus vannamei
Authors: Bai X , Feng S , Ye G , Jiang J , Wu H , Tang H , Zhang Z , Hao S , Guo J , Luo Z
Published: February 2021

β-glucan is an effective, available immunostimulant that has been successfully used to improve the immune defense of shrimp against pathogenic infection. However, the long-term continuous use of β-glucan can lead to immune fatigue, and intermittent feeding may be an effective way of avoiding this phenomenon. A 60-day growth trial was conducted to compare the effects of different feeding strategies of diets containing 200 mg/kg β-glucan on the growth and immune system of the Pacific white shrimp Litopenaeus vannamei. The results showed that either continuous feeding or intermittent feeding of diets containing 200 mg/kg β-glucan did not promote the growth of L. vannamei. However, the levels of superoxide dismutase, alkaline phosphatase, and acid phosphatase in the hepatopancreas of L. vannamei in the intermittent feeding group were significantly higher than those in the control and continuous feeding groups. Expression levels of the genes encoding LPS/β-glucan binding protein, superoxide dismutase, lysozyme, penaeid in-3a, and catalase were also significantly upregulated in the intermittent feeding group, whereas most of the immune parameters in the continuous feeding group were not significantly different from those of the control group. After artificial infection with Vibrio parahaemolyticus, the average mortality rates in the control group, the continuous feeding group, and the intermittent feeding group were 76.67%, 78.89%, and 45.56%, respectively. The results indicated that the addition of 200 mg/kg β-glucan to the diet did not promote the growth of L. vannamei, but the strategy of intermittent feeding effectively prevented immune fatigue and enhanced disease resistance, perhaps by increasing nonspecific immunity in L. vannamei.
Effects of High Carbohydrate and Benfotiamine on the Growth and Feed Efficiency of Juvenile Nile Tilapia, Oreochromis niloticus
Authors: Serrano AE Jr. , Tumbokon BL , Canillo SDT , Lauzon QD
Published: February 2021

This study aimed to evaluate the effects of a high carbohydrate diet (HC) alone and HC supplemented with benfotiamine (HCB), a human anti-diabetic supplement, on the growth performance of Nile tilapia fry, Oreochromis niloticus. A total of 180 Nile tilapia fry (AWB=0.01g) were randomly distributed to 9 tanks and fed one of three experimental diets, namely, a control diet containing 15% carbohydrate; high carbohydrate diet (HC) containing 25% carbohydrate; and high carbohydrate diet (25%) supplemented with 0.02% benfotiamine (HCB) for 8 weeks. Increasing corn starch in the diet from 15% (i.e. control diet) to 25% (i.e. HC diet) did not have any effect on the growth performance nor feed efficiency of the Nile tilapia. In contrast, Nile tilapia fed the HCB diet exhibited significantly the highest final average body weight, weight gain, specific growth rate, feed intake and whole-body lipid content and the most efficient FCR among the treatments. Results of the attractability tests showed that the HCB diet significantly attracted the most percentage of fish. In conclusion, the findings indicated that the Nile tilapia efficiently utilized an increase of carbohydrate from 15% to 25% and that dietary benfotiamine significantly increased the utilization of this diet, enhancing further its growth performance and feed utilization; benfotiamine also increased the attractability of the diet.
Effects of Housefly Maggot Meal and Earthworms on Growth and Immunity of the Asian Swamp Eel Monopterus albus (Zuiew)
Authors: Yi T-L , Yang D-Q , Yang C. , Pei M-T
Published: February 2021

Fly larvae (maggot meal) and earthworms are promising potential replacements for increasingly expensive and unsustainable fishmeal. Apart from being a good protein source, fly larvae also contain substances with immunostimulant capacity, however the impact of their inclusion in feed on the immune system remains only partially understood. To address this, we studied the effects of four diets with varying levels of earthworm (40-70%) and maggot meal (0-30%) on growth and immunocompetence of juvenile Asian swamp eels Monopterus albus (fish n = 480, duration = 40 days). Maggot meal inclusion resulted in a significantly (P<0.05) higher total protein, glutamic pyruvic transaminase activity, anti-oxidizing enzyme and lysozyme activity, and significantly lower triglycerides, in the blood serum. Bacterial (Aeromonas hydrophila) challenge test results showed that adding maggot meal to the feed improved survival rate and immunocompetence at all three tested inclusion ratios. The strongest positive impact on most studied parameters (including 50% higher survival and 21.4% higher immunocompetence) was observed in the 20% inclusion group. As positive effects were slightly lower at the 30% level, the optimal combination of the two ingredients was 20% maggot meal and 50% earthworms
Parentage Assignment in Striped Catfish (Pangasianodon hypophthalmus) Based on Microsatellite Marke
Authors: Nguyen T.L , Le Nguyen T.P , Nguyen M.T , Duong A.L
Published: February 2021

In this study, five microsatellite markers from two multiplex PCR sets were used to determine the pedigree of five striped catfish (Pangasianodon hypophthalmus) families that came from a breeding program in Vietnam. The number of alleles per locus and polymorphic information content (PIC) were 4 to 7 and 0.551-0.803, respectively. In the parentage analysis based on five microsatellites, 62.7% of offspring could be allocated unambiguously to their parental pairs using the perfect mismatch setting, and assignment rate improved to 89.3% after a single mismatch was allowed. Parentage analysis when only four microsatellites were used (a locus with a high frequency of null alleles was excluded) increased the assignment rate to 68% for a perfect mismatch and to 90% for assignment with a single mismatch. Results here confirm that a DNA markerbased approach to parentage assignment in P. hypophthalmus will be useful in genetic improvement programs for this important aquaculture species in Vietnam. .
Community Health Officer Post – Potential Concerns
Authors: Jani Vishalkumar J
Published: February 2021

Under Ayushman Bharat Health and Wellness Centre (HWC) initiative, a middle-level health provider post, named Community Health Officer (CHO), is envisioned to bridge the gap between the health system and community. This cadre has multiple roles and responsibilities that mirror what used to be done by the Auxiliary Nurse Midwife (ANM) at sub-center before conversion to HWC. Owing to educational and experience requirements of CHO, and existing other cadres at the sub-center, there may be some concerns related to role ambiguity, interpersonal issues, inter- and intra-cadre conflicts, and non-cooperation challenges.
Intentional self-harm associated mortality among U.S. White physicians, nurses, lawyers & judges
Authors: Gupta Deepak , Kumar Sarwan , Chakrabortty Shushovan
Published: February 2021

The mortality associated factors can be quantified in terms of proportionate mortality ratios (PMR) per National Occupational Mortality Surveillance (NOMS) data. Therefore, we explored NOMS data for the United States (U.S.) occupational workers’ mortality during 1999, 2003-2004, 2007-2014 to compare physicians’ mortality associated factors to the mortality associated factors among nurses vs. the mortality associated factors among lawyers & judges. Due to lack of adequate sample sizes of decedents being concurrently present among physicians, nurses, and lawyers & judges of Black race, we were able to tabulate 25 causes of death with significant PMRs among physicians, nurses, and lawyers & judges only of White race. Therein, intentional self harm associated mortality was found to be common among U.S. White physicians, nurses, lawyers & judges.
A abordagem empreendedora no ensino do jornalismo como forma de superar o mercado informal
Authors: Silveira Renan
Published: February 2021

Existem inúmeros fenômenos que nos levam a pensar no jornalismo com uma profissão em crise. Certas rupturas enfrentadas pelo setor visivelmente não estão restritas a um fator exclusivo. Dessa forma evidenciamos especificamente: a não-obrigatoriedade do diploma para o exercício da profissão, e o aumento de publicações que passam a estar disponíveis gratuitamente na internet. Por esses motivos, somado ao surgimento de aparelhos eletrônicos capazes de divulgar informações em tempo real, a real necessidade do jornalista frente à sociedade é questionada. Na mesma medida em que faz indivíduos comuns aderir ao jornalismo amador, democratizando a informação, abre caminho para a divulgação deliberada de publicações mal apuradas e/ou mal-intencionadas, geralmente com tom noticioso. Isto sem citar fake news que se aproveitam dessa ruptura dos meios tradicionais para se apresentarem como “verdades alternativas”. Frente a esses problemas, propomos, por meio de uma revisão bibliográfica de conceitos e métodos práticos, o incentivo do empreendedorismo pelas Instituições de Ensino Superior (IES) dentro dos cursos de jornalismo. A partir de então, profissionais com a devida formação serão incentivados a ocupar espaços que, apesar de concentrarem grandes nichos de público, são atualmente desdenhadas pela maioria dos bons jornalistas. O eventual êxito desta proposta tende a reconquistar mercado para a categoria, além de conteúdo de qualidade para a sociedade.
IMPROVING STUDENTS' LEARNING OUTCOMES IN ENGLISH THROUGH DISCOVERY LEARNING LEARNING MODEL
Authors: Nuraini Nuraini
Published: February 2021

Penelitian ini bertujuan untuk meningkatkan hasil belajar Bahasa Inggris siswa melalui penerapan model pembelajaran discovery learning kelas XII MIA SMA Negeri 1 Syamtalira Aron tahun pelajaran 2019/2020. Penelitian ini dilaksanakan pada semester I (ganjil). Waktu pelaksanaan penelitian ini adalah dimulai pada bulan Juli sampai dengan bulan September tahun 2019 mulai dari perencanaan, pelaksanaan penelitian dan pembuatan laporan. Subjek penelitian ini adalah siswa kelas XII MIA 4 SMA Negeri 1 Syamtalira Aron sebanyak 30 siswa tahun pelajaran 2019/2020. Prosedur penelitian ini menggunakan desain penelitian tindakan kelas yang dilakukan dalam dua siklus. Teknik pengumpulan data yang digunakan dalam penelitian ini adalah melalui observasi aktivitas guru melaksanakan pembelajaran, observasi aktivitas siswa dalam pembelajaran dan tes hasil belajar siswa. Teknik analisi data yang digunakan adalah deskriptif kualitatif dengan perhitungan persentase. Hasil penelitian menunjukan pada siklus I persentase ketuntasan klasikal hasil belajar siswa sebesar 70% sedangkan pada siklus II sebesar 100%, mengalami peningkatan sebesar 30%. Aktivitas guru melaksanakan pembelajaran pada siklus I sebesar 66,7% sedangkan pada siklus II sebesar 91,7%, mengalami peningkatan sebesar 25%. Aktivitas siswa dalam pembelajaran pada siklus I sebesar 58,8% sedangkan pada siklus II sebesar 92,1%, mengalami peningkatan sebesar 33,3%. Sehingga dapat disimpulkan bahwa penerapan model pembelajaran discovery learning dapat meningkatkan hasil belajar bahasa inggris siswa kelas XII MIA SMA Negeri 1 Syamtalira Aron tahun pelajaran 2019/2020.
PENGARUH METODE PEER TEACHING TERHADAP HASIL BELAJAR MAHASISWA PADA MATERI OPERASI ALJABAR
Authors: Akmal Nurul
Published: February 2021

Matematika salah satu pelajaran penting dalam membentuk pola pikir mahasiswa karena matematika melatih untuk berpikir kritis dan sistematis. Tujuan penelitian ini adalah untuk melihat pengaruh hasil belajar mahasiswa yang belajar menggunakan metode peer teaching dengan metode biasa pada materi operasi aljabar. Populasi dalam penelitian ini adalah mahasiswa semester satu, sampel yang diambil adalah mahsiswa semester satu yang berjumlah 50 orang berdasarkan purposive sampling. Jenis penelitian yang digunakan adalah kuantitatif. Instrumen penelitian menggunakan tes berbentuk soal uraian. Analisis data menggunakan uji non parametric Mann Witney U. Hasil Penelitian menunjukkan bahwa terdapat pengaruh yang signifikan hasil belajar mahasiswa yang menggunakan metode peer teaching dengan kelas kontrol yang menggunakan metode biasa
Incorporation of Rice Husk Ash with Palm Oil Mill Wastes in Enhancing Physicochemical Properties of the Compost
Authors: Hisham Nur Eliza Badrul , Ramli Nor Hanuni
Published: February 2021

Rice husk ash (RHA), palm oil mill effluent (POME) sludge and decanter cake can be utilized together in compost production to minimize the environmental pollution. This study aims to evaluate the role of different composition of RHA in enhancing the physicochemical properties of palm oil-based compost. The composts were prepared by mixing different composition of RHA, in the range of 0% to 30%, with 1:1 (wt/wt) weight ratio of POME sludge and decanter cake. The moisture content, water holding capacity, pH, nitrogen (N), phosphorus (P), potassium (K), silica (Si) contents, and C:N ratio of raw materials were analyzed by using CHNS and WDXRF analyzers. The composting process was conducted in compost containers for 60 days, in which the temperature and pH of the composts were monitored daily. The finished composts were analyzed for physicochemical properties as same as raw materials. For physical properties of finished composts, RHA30 had the highest moisture content and water holding capacity which was 1.9 to 23.8% (wt/wt) and 4.2 to 26.8% higher compared to other finished composts, respectively. For chemical properties, the highest N and P contents were recorded by control compost. However, for K and Si content, the elements were found to be higher in RHA10 and RHA30, respectively, compared to other finished composts. Overall, RHA, POME sludge and decanter cake combination in compost production can create a well-balanced condition for the compost to perform effectively as an organic fertilizer. The addition of 5% to 10% RHA in compost formulation made from palm oil mill wastes is suggested to achieve the desirable condition.
“Joguei a toalha!”: a realidade de executivas que decidiram retornar ao lar: uma discussão sobre o fenômeno opt-out
Authors: Reis Sally Joice , Mota-Santos Carolina Maria , Teixeira Marcella Barbosa Miranda
Published: February 2021

O presente artigo tem o objetivo de compreender os motivos que levam algumas executivas a desistirem da carreira e optarem pelo retorno ao lar. Trata-se de estudo com abordagem qualitativa, por meio do método história de vida. A coleta de dados ocorreu a partir de entrevista em profundidade, utilizando como sujeitos duas mulheres executivas. A pesquisa convoca a uma reflexão sobre esse posicionamento de desistência, uma vez que historicamente, há uma divisão entre os sexos, aspecto que permite compreender porque as mulheres encontram muitos desafios no que diz respeito à ascensão e à manutenção de sua carreira no mundo corporativo. A grande contribuição deste estudo foi a de avançar nos motivos que levam ao fenômeno opt-out, pouco explorado na literatura.
L’éducation en tant que pratique de la liberté est-elle toujours d’actualité au Paraguay ?
Authors: Demelenne Dominique
Published: February 2021

Pour Freire, l’éducation en tant que pratique de la liberté est une production de connaissance qui ne se termine pas avec l’objet de la connaissance, mais bien dans le processus de communication avec d’autres sujets également cognitifs. Elle s’inscrit donc dans une perspective communicationnelle liée à la praxis et à la conscientisation. De cette façon, la connaissance se construit à partir des relations entre l’Homme et le monde, et se perfectionne dans la problématisation critique de ses relations. Il s’agit donc de relations liées à la transformation. A partir de cette perspective freirienne de la transformation à travers l’éducation, ce texte cherche à vérifier la pertinence et la validité de cette méthode dans le contexte actuel du Paraguay, pays qui a mis en marche ces dernières années un processus de transformation éducative. Pour tenter de comprendre la pertinence du projet de Freire aujourd’hui, il faudra l’inscrire dans un nouveau contexte de changements socioculturels et sociopolitiques. Pour ce faire, nous partirons de l’étude d’un cas précis : la gestion du programme Escuela Viva. Cette analyse nous permettra de découvrir les aspects à prendre en compte pour la définition et la gestion d’un projet de transformation éducative.
Das Spiel zeigt den Charakter
Authors: Reckert Klaus
Published: February 2021

Spiele für den Ingenieur: Es gibt Recruiting Games, die den idealen Ingenieur als Kandidaten für einen bestimmten Job herausfiltern sollen. Und es gibt Spiele, die den inneren Ingenieur fordern und fördern wollen. Ein exemplarischer Überblick. Von Klaus Reckert
Three’s a crowd or bonus?: College students’ threesome experiences
Authors: Morris Hannah , Chang I. Joyce , Knox David
Published: February 2021

Undergraduates (196) at a large southeastern university completed a 59 item Internet survey on threesome attitudes and behaviors. Fifteen percent of the sample reported having engaged in a threesome. Men evidenced more interest in having a threesome than women and persons most likely to report having had a threesome held hedonistic compared to relativistic or absolutist sexual values. The motivation for a threesome was primarily curiosity and the third person invited to join the couple in a threesome was most often a friend/acquaintance of the woman. The outcome of a threesome for the couple was primarily no effect with a about a fifth reporting negative outcomes and a similar percentage reporting positive outcomes. Finally, the event happened only once for 83% of the respondents who had a threesome. Symbolic interaction, operant learning, social learning, affective theory and feminist theory were used to interpret the data. Implications and limitations are identified.
Response and Economic Efficiency of Broiler Chickens fed graded levels of Baker's Yeast (Saccharomyces cerevisiae) supplement
Authors: Buba W. , Olugbemi T. S. , Omage J. J. , Duru S. , Iyiola-Tunji A. O.
Published: February 2021

Two hundred and fifty-five day-old Ross White strain broiler chicks were used to evaluate the Response and economic efficiency of broiler chickens fed graded levels of baker's yeast (saccharomyces cerevisiae) supplement during the harmattan season in the northern guinea savannah zone of Nigeria. There were five treatment groups for both starter and finisher phases. The experiment lasted for eight weeks. Each treatment group had three replicates with 17 birds per replicate and fifty-five birds per group in a completely randomized design (CRD). Treatments 1, 2, 3, 4 and 5 contained 0.0, 0.5, 1.0, 1.5 and 2.0% SC respectively. Results of the starter phase showed significant (P<0.05) differences in terms of final weight gain and feed conversion ratio (FCR). Treatment groups fed the control diet (0.0%), 0.5% and 1% SC had the best final body weight and body weight gain during the starter phase. The FCR was significantly (P<0.05) higher in the treatment group fed 0.5%SC during the starter phase. Mortality was higher (11.76%) in the control group compared to other treatment groups in the starter phase. During the finisher phase, treatment group fed 1.0% SC had significantly (P<0.05) higher final body weight, body weight gain and FCR. Apparent digestibility of crude protein, crude fibre, ether extract, ash, dry matter and nitrogen free extract were better in treatment groups containing SC. The economic efficiency results of this study indicated that the birds fed 1.0% SC were more profitable compared to those fed the control diet. The net profit of the treatment group fed 1.0% SC was N 650.01 compared to the control (N554.35). This study concluded that the optimum inclusion level of Baker's yeast (Saccharomyces cerevisiae) in the diet of broilers starter was 0.5% and 1.0% for finisher diet for improved performance in terms of weight gain and feed conversion ratio (FCR). It is suggested that broiler chicken farmers should be encouraged to include Baker's yeast in the diet of broiler chickens for improved weight productivity and better feed utilization.
Global modeling studies of composition and decadal trends of the Asian Tropopause Aerosol Layer
Authors: Bossolasco Adriana , Jegou Fabrice , Sellitto Pasquale , Berthet Gwenaël , Kloss Corinna , Legras Bernard
Published: February 2021

Abstract. The Asian summer monsoon (ASM) traps convectively lifted boundary layer pollutants inside its upper-tropospheric lower-stratospheric
Asian monsoon anticyclone (AMA). It is associated with a seasonal and
spatially confined enhanced aerosol layer, called the Asian Tropopause Aerosol Layer (ATAL). Due to the dynamical variability of the AMA, the
dearth of in situ observations in this region, the complexity of the
emission sources and of transport pathways, knowledge of the ATAL properties in terms of aerosol budget, chemical composition, as well as its
variability and temporal trend is still largely uncertain. In this work, we use the Community Earth System Model (CESM 1.2 version) based on the
coupling of the Community Atmosphere Model (CAM5) and the MAM7 (Modal
Aerosol Model) aerosol module to simulate the composition of the ATAL and
its decadal trends. Our simulations cover a long-term period of 16 years
from 2000 to 2015. We identify a typical “double-peak” vertical profile of
aerosols for the ATAL. We attribute the upper peak (around 100 hPa,
predominant during early ATAL, e.g., in June) to dry aerosols, possibly from nucleation processes, and the lower peak (around 250 hPa, predominant for a
well-developed and late ATAL, e.g., in July and August) to cloud-borne
aerosols associated with convective clouds. We find that mineral dust
(present in both peaks) is the dominant aerosol by mass in the ATAL, showing
a large interannual variability but no long-term trend, due to its natural
variability. The results between 120 and 80 hPa (dry aerosol peak) suggest that for aerosols other than dust the ATAL is composed of around 40 % of
sulfate, 30 % of secondary and 15 % of primary organic aerosols, 14 %
of ammonium aerosols and less than 3 % of black carbon. Nitrate aerosols
are not considered in MAM7. The analysis of the anthropogenic and biomass
burning aerosols shows a positive trend for all aerosols simulated by
CESM-MAM7.