Supplementation of Bacillus subtilis and Lactobacillus casei to increase growth performance and immune system of catfish (Clarias gariepinus) due to Aeromonas hydrophila infection

Background and Aim

Catfish has a high economic value and is popular among consumers. To ensure well-stocked catfish stocks, good fisheries management must also be ensured. The high demand for catfish must be supplemented by preventive measures against pathogenic bacterial infections using probiotics with high potential for Lactobacillus casei and Bacillus subtilis. The aim of this study was to determine the effect of probiotic supplementation consisting of a combination of L. casei and B. subtilis probiotics on the growth, immune system, water quality, proximate value of feed, and body composition of catfish infected with Aeromonas hydrophila.

Materials and Methods

This study used a completely randomized study with eight treatments and three replications. The manipulated factor was the probiotic concentration [0% (A), 0.5% (B), 10% (C), and 15% (D)] in groups of catfish infected and uninfected with A. hydrophila. Combination of B. subtilis, and L. casei that were used in a 1:1 ratio of 108 colony forming unit/mL. The study lasted for 42 days. On the 35th day, A. hydrophila was infected by intramuscular injection into fish. The Statistical Package for the Social Sciences (SPSS) software version 23.0 (IBM SPSS Statistics) was used to analyze data on growth, immune system, and water quality.

Results

Providing probiotics in feed can increase the nutritional value of feed based on proximate test results. There were significant differences in average daily gain (ADG), feed conversion ratio (FCR), and survival rate (SR) parameters in the group of catfish infected with A. hydrophila (p > 0.05); however, there were no significant differences in final body weight, specific growth rate (SGR), and percentage weight gain. Interleukin-1β (IL-1β) levels were significantly different between treatments C and D. The tumor necrosis factor (TNF) α parameters were significantly different between treatments A and C, whereas the phagocytic activity of treatment A was significantly different from that of treatment D. There was a significant difference (p > 0.05) in the growth parameters of SGR, ADG, and FCR in the group of fish that were not infected with A. hydrophila, with the best treatment being a probiotic concentration of 15%, but there was no significant difference in the SR parameters. IL-1β and TNF-α levels significantly differed between E and E0 (15% probiotics) but were not significantly different in terms of phagocytosis parameters.

Conclusion

Based on the results of this study, it can be concluded that using a combination of probiotics L. casei and B. subtilis can improve the growth, immune system, water quality, proximate value of feed, and body composition of catfish infected with A. hydrophila.

Mitogenomic Characterization and Phylogenetic Placement of African Hind, Cephalopholis taeniops: Shedding Light on the Evolution of Groupers (Serranidae: Epinephelinae)

The global exploration of evolutionary trends in groupers, based on mitogenomes, is currently underway. This research extensively investigates the structure of and variations in Cephalopholis species mitogenomes, along with their phylogenetic relationships, focusing specifically on Cephalopholis taeniops from the Eastern Atlantic Ocean. The generated mitogenome spans 16,572 base pairs and exhibits a gene order analogous to that of the ancestral teleost's, featuring 13 protein-coding genes (PCGs), two ribosomal RNA genes (rRNAs), 22 transfer RNA genes (tRNAs), and an AT-rich control region. The mitogenome of C. taeniops displays an AT bias (54.99%), aligning with related species. The majority of PCGs in the mitogenome initiate with the start codon ATG, with the exceptions being COI (GTG) and atp6 (TTG). The relative synonymous codon usage analysis revealed the maximum abundance of leucine, proline, serine, and threonine. The nonsynonymous/synonymous ratios were <1, which indicates a strong negative selection among all PCGs of the Cephalopholis species. In C. taeniops, the prevalent transfer RNAs display conventional cloverleaf secondary structures, except for tRNA-serine (GCT), which lacks a dihydrouracil (DHU) stem. A comparative examination of conserved domains and sequence blocks across various Cephalopholis species indicates noteworthy variations in length and nucleotide diversity. Maximum likelihood, neighbor-joining, and Bayesian phylogenetic analyses, employing the concatenated PCGs and a combination of PCGs + rRNAs, distinctly separate all Cephalopholis species, including C. taeniops. Overall, these findings deepen our understanding of evolutionary relationships among serranid groupers, emphasizing the significance of structural considerations in mitogenomic analyses.

Detecting DNA of multispecies dinoflagellate cysts in the sediment from three estuaries of Makassar strait and fishing port using CO1 primer: Is it CO1 primer suitable for detecting DNA dinoflagellate?

Most dinoflagellate had a resting cyst in their life cycle.  This cyst was developed in unfavorable environmental condition. The conventional method for identifying dinoflagellate cyst in natural sediment requires morphological observation, isolating, germinating and cultivating the cysts.  PCR is a highly sensitive method for detecting dinoflagellate cyst in the sediment.  The aim of this study is to examine whether CO1 primer could detect DNA of multispecies dinoflagellate cysts in the sediment from our sampling sites. Dinoflagellate cyst DNA was extracted from 16 sediment samples. PCR method using COI primer was running. The sequencing of dinoflagellate cyst DNA was using BLAST. Results showed that there were two clades of dinoflagellate cysts from four locations of study.  Clade 1 was dominated by samples from the Jeneberang Estuary (JB), Maros Estuary (M) and Pangkep Estuary(P), while clade 2 was dominated by samples from the Paotere Port (PP). The genetic distance varied between DNA dinoflagellate cyst samples ranging from 0.5 -0.6. The closest genetic distance was between sample of JB1 and sample of JB2, while the farthest genetic distance was sample PP1 and PP2. The primer CO1 was not suitable for dinoflagellate cyst DNA due to only picking one DNA, which was a diatom (Licmophora sp).

Environmental DNA metabarcoding reveals biodiversity marine fish diversity of a small island at Manokwari District, West Papua, Indonesia

Abstract. Pranata B, Kusuma AB, Sabariah V, Kim HW, Andriwiyono S. 2022. Environmental DNA metabarcoding reveals biodiversity marine fish diversity of a small island at Manokwari District, West Papua, Indonesia. Biodiversitas 23: 5982-5988. The uniqueness of small island biodiversity becomes very important to study. Molecular approaches to collecting biodiversity information are currently quite developed. Manokwari district, which is located at the head of Papua Island, Indonesia, has very diversity of marine resources, especially coral reef fish. Currently, we successfully identified marine fish in the coral reef fish ecosystem of Lemon and Mansinam Island. Environmental DNA on Lemon Island and Mansinam Island was successfully carried out. This small island area is located in Manokwari District, Papua, which has a high biodiversity potential, including fishery resources. The MiFish pipeline is used in this Metabarcoding approach by combining water samples from Lemon Island and Mansinam Island. We filtered 1 liter of marine water and pool together from fourteen sampling sites for genomic DNA extraction. A total of 101,001 reads (88.31%) were assigned to 34 species. From the environmental DNA metabarcoding analysis results, the Pomacentridae (8 species), which are reef fish, dominate in this area. Besides, Acanthuridae, Carangidae, and Lutjanidae were identified in this area, which as coral reef fish associates. The results of this environmental DNA also identified 2 species from the Family Scombridae, namely Gymnosarda unicolor and Thunnus obesus. This information is expected to support the sustainable management of the Lemon Island and Mansinam Island Areas for tourism and conservation activities.

The complete mitochondrial genome of the Korean endemic species Cobitis hankugensis (Kim, Park, Son & Nalbant, 2003)

As one of efforts to conserve a genetic resource of the endemic cobitid species in the Korean peninsula, the complete mitogenome of Cobitis hankugensis (Kim, Park, Son & Nalbant, 2003) was determined using Illumina MiSeq system. The circular mitogenome was 16,557 bp length and encoded 13 protein-coding genes (PCGs), two ribosomal RNA genes, 22 tRNA genes, and a control region. Only the COX1 gene was identified with an aberrant initiation codon GTG, and an incomplete termination codon (T—/TA–) was identified in six PCGs including COX2, COX3, ND2, ND3, ND4, and Cytb genes. Phylogenetic analysis using 30 mitochondrial genomes belonging to Cobitidae, Botiidae, and Gyrinocheilidae showed that the highest identity (92.38%) with Kichulchoia brevifasciata (NC_027166). The complete mitogenome of C. hankugensis, an endemic species in Korea, will provide fundamental data on the evolutionary relationship of Cobitidae species.

The complete mitochondrial genome of the longneck croaker, pseudotolithus typus Bleeker, 1863 from Sierra Leone

The complete mitochondrial DNA information of Pseudotolithus typus Bleeker, 1863, collected from Sierra Leone was determined using next-generation sequencing (NGS) and bioinfromatic analysis. Its mitogenome (16,504 bp) encoded the typical 13 protein-coding genes (PCGs), 2 ribosomal RNAs (12S & 16S), and 22 tRNAs. All 13 PCGs showed a standard start codon (ATG) but an unusual stop codon (AGA) was identified in COX1 gene. Except for ND6, all 12 PCGs were encoded on the light strand. Except for tRNA^Ser-GCT, 21 tRNAs formed the typical clover-leaf structures. Phylogenetic analysis showed three mitochondrial genomes in the genus Pseudotolithus formed a clade distinct from the other species in the same family. The mitogenome of P. typus identified in this study exhibited 96.27% and 88.86% identity to T. typus in the Guinean water and P. elongatus, respectively. Additional mitogenome sequences of Pseudotolithus species will provide useful information for their scientific management in western African countries.

Characterization of the complete mitochondrial genome of the Northern Mud Gudgeon, Ophiocara porocephala (Perciformes: Eleotridae) with phylogenetic implications

The first mitochondrial genome of Ophiocara porocephala was determined by the combination of next-generation sequencing (NGS) and Sanger sequencing methods. A complete circular mitogenome of O. porocephala (16,529 bp) consisted of 13 protein-coding genes, 22 transfer RNAs, two ribosomal RNAs, and two non-coding regions, including a control region (D-loop) and a light strand origin of replication (O_L). Two start codons (ATG and GTG) and four stop codons (TAG, TAA, TA-, and T-) were used in all the PCGs. Except for ND6 and eight transfer RNAs (tRNAs), all the other genes were encoded in the heavy strand. Based on phylogenetic analysis, O. porocephala formed a clade with three other species in the subfamily Butinae, while the other 10 made a subfamily Eleotrinae clade.

Assessment of fish biodiversity in four Korean rivers using environmental DNA metabarcoding

Environmental DNA (eDNA) metabarcoding is a cost-effective novel approach to estimate biodiversity in an ecosystem. In this study, the MiFish pipeline was employed to test if the system methodology is sufficiently reliable to estimate fish biodiversity in Korean rivers. A total of 125 unique haplotypes and 73 species were identified at the species level from 16 water samples collected from a single survey in four Korean rivers (Hyeongsan, Taehwa, Seomjin, and Nakdong). Among the four rivers, the highest species richness was recorded in the Seomjin River (52 species), followed by the Taehwa (42 species) and Hyeongsan (40 species) rivers. The Nakdong River (26 species) presented the lowest species richness and number of endemic species, presumably due to its metropolitan location and anthropogenic impacts, such as dams or weirs. We were also able to detect that five exotic species (Carassius cuvieri, Cyprinus carpio, Cyprinus megalophthalmus, Lepomis macrochirus, and Micropterus salmoides) are widely distributed in all surveyed rivers, a situation that might be problematic in terms of conservation. Our findings indicate that the eDNA metabarcoding technique is one of the most cost-effective scientific tools available for the management and conservation of the freshwater fish resources available in Korea. However, the low number of 12S sequences of endemic species in the database and low resolution of the MiFish region for differentiating several taxa should be upgraded for their wide use.

Environmental DNA (eDNA) metabarcoding: Diversity study around the Pondok Dadap fish landing station, Malang, Indonesia

Abstract. Andriyono S, Jobaidul Alam Md, Kim HW. 2019. Environmental DNA (eDNA) metabarcoding: Diversity study around the Pondok Dadap fish landing station, Malang, Indonesia. Biodiversitas 20: 3772-3781. Molecular identification of species is now fast growing and currently widely applied method in the diversity estimation of aquatic biota; even though morphological identification is still carried out. The molecular approach is beneficial complementing on regular surveys, e.g. use of nets, traps, fishing rods, and even with poisons. In this study, the eDNA metabarcoding was applied to water samples around the Pondok Dadap fish landing station, Indonesia to determine the diversity of fish around the waters and also to identify marine fish landed in this area. Molecular identification was carried out on fish samples obtained from the fish market improved GenBank database on COI and ITS. While, seawater samples were carried out by using the next-generation sequencing (NGS) platform to obtain the eDNA metabarcoding data for the first time. Molecular identification obtained 34 species (68 sequences of COI and ITS regions) belonging to 28 genera, 18 families, 4 orders, while the eDNA metabarcoding approach identified 53 marine fish species by using the MiFish pipeline representing 38 genera, 27 families, and 7 orders. From the present study, we can able to estimated fish diversity by eDNA metabarcoding, and this finding will be helpful for baseline data preparation for future effective management of resources in this area.

Characterization of the complete mitochondrial genome of Chionobathyscus dewitti (Perciformes, Channichthyidae)

The complete mitochondrial genome sequence of the Icefish, Chionobathyscus dewitti was determined by the Next Generation Sequencing (NGS) analysis. The complete mitogenome was 17,452 bp in length, which encoded the canonical 13 protein-coding genes, 22 tRNAs, two rRNAs, and two non-coding regions. As shown in the other notothenids, translocation of ND6 and an additional non-coding region were identified, which is different from the typical vertebrate mitochondrial genomes. The C. dewitti was clustered distinctly from the those in the Chinodraco and Chaenocephalus, which supported the idea that this species should be classified in the different genus, Chionobathyscus in the family Channichthyidae.

Characterization of the complete mitochondrial genome of Odontobutis platycephala collected from Nakdong River, South Korea

The complete mitochondrial genome of Odontobutis platycephala collected from a native Korean river was determined by the bioinformatics assembly of the next-generation sequencing (NGS) reads. The circular mitogenome was 17,590 bp length which harbored canonical 13 protein-coding genes, 22 tRNAs, and 2 rRNAs, which was identical to those of family Odontobutidae. Twenty-eight genes were located on H strand, whereas remaining nine genes were on L strand. Except for COX1 gene (GTG), other 12 protein-coding genes were predicted typical start codons (ATG). Among the currently known mitogenome sequences, O. platycephala showed highest identity (96.98%) to Korean haplotype of O. platycephala (NC010199).

Characterization of the complete mitochondrial genome of Silurus soldatovi in Korean river

The complete mitochondrial genome of Silurus soldatovi firstly collected from a native Korean river was determined by the bioinformatics assembly of the next-generation sequencing (NGS) reads. The circular mitogenome was 16,525 bp in length which harbored canonical 13 protein-coding genes, 22 tRNAs, and 2 rRNAs, which was identical to those of family Siluridae. Twenty-eight genes were located on H strand, whereas the remaining nine genes were on L strand. Except for COX1 gene (GTG), other 12 protein-coding genes were predicted typical start codons (ATG). Among the currently known mitogenome sequences, S. soldatovi showed highest identity (99.38%) to the Chinese haplotype of S. soldatovi (NC022723) followed by the Chinese haplotype of Silurus asotus (JX087351). Interestingly, intraspecies variations of S. asotus are higher than those of interspecies and further study should be made to elucidate the evolutional relationship between two Silurus species.

Complete mitochondrial genome of green shrimp, Chlorotocus crassicornis (Crustacea: Decapoda: Pandalidae) in Korean water

The complete mitochondrial genome of green shrimp, Chlorotocus crassicornis (Costa, 1871) was generated by the combination of next-generation sequencing platform and long PCR technique. The mitochondrial genome of C. crassicornis was 16,500 bp, in which 13 protein-coding genes, two ribosomal RNAs, 22 transfer RNAs, and a putative control region was encoded. Based on the 13 protein-coding genes region, the phylogenetic tree was clearly demonstrated that C. crassicornis is closest to Pandalopsis japonica and Pandalus borealis with 77% identity. This mitogenome information will be helpful for the further studies of deep-sea fisheries resources management strategies in Korea including C. crassicornis species.

Characterization of the complete mitochondrial genome of Gangetic ailia, Ailia coila (Siluriformes: Ailiidae)

The first complete mitochondrial genome sequence of Ailia coila from Bangladesh was determined by the bioinformatic assembly of the next generation sequencing (NGS) reads. The constructed circular mitogenome for A. coila was 16,565 bp in length which harbored the canonical 13 protein-coding genes, 22 tRNAs, 2 rRNAs. Two non-coding regions, control region, D-loop (927 bp), and origin of light strand replication, O_L (30 bp) were also well conserved in the mitogenome. Among the currently reported mitochondrial genomes in the order Siluriformes, A. coila was most closely related to Eutropiichthys vacha (AB919123) with 85.63% sequence identity.

The complete mitochondrial genome of the Argentine red shrimp Pleoticus muelleri (Bate, 1888) (Crustacea, Decapoda, Solenoceridae)

The complete mitochondrial genome of Argentine red shrimp, Pleoticus muelleri (Bate, 1888) was determined using the MiSeq platform. Its mitogenome (16,189 bp) encoded the canonical 13 protein-coding genes, 22 tRNA genes, two rRNA genes. Start codons of all protein-coding genes were ATN except for ATP8, while incomplete stop codons (T-) were identified in six genes including COXI, COXII, COXIII, NAD3, NAD5, and NAD6. The mitogenome of P. muelleri showed highest sequence identity with Parapenaeopsis hardwickii (82%) and Solenocera crassicornis (81%). Phylogenetic analysis showed three shrimps in Solenoceridae including P. muelleri were grouped together from those in Penaeidae, which suggests taxonomic reexamination for those in those family.

Complete mitochondrial genome of brownstripe red snapper, Lutjanus vitta (Perciformes: Lutjanidae)

The complete mitochondrial genome of the brownstripe red snapper, Lutjanus vitta was determined by MiSeq sequencing platform. The mitogenome of L. vitta (16,498 bp) encoded the typical 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and two non-coding regions (origin of light strand replication; O_L and D-Loop control region; CR). Phylogenetic analysis based on the full mitochondrial genome sequences showed that L. vitta is most closely related to L. russellii. The complete mitogenome sequence of L. vitta would provide the information of the genetic biodiversity in Lutjanus fishes, which would be further used for their scientific management in Indonesian waters.

Characterization of complete mitochondrial genome of two-spot swimming crab Charybdis bimaculata (Miers, 1886)

The two-spot swimming crab Charybdis bimaculata (Miers, 1886) is an important decapod species in the benthic ecosystem of Korean waters. In this study, we determined its complete mitochondrial genome by the combination of NGS analysis using MiSeq platform and PCR-based cloning method. The circular mitochondrial genome of C. bimaculata was 15,714 bp in length in which the standard set of 13 protein-coding genes, 22 tRNA genes, and 2 rRNA genes were encoded. Phylogenic analysis showed that C.bimaculata is most closely related to Charybdis feriata. The complete mitogenome sequence information of C. bimaculata would provide useful data for the conservation of their population in the Pacific ocean.

Complete mitochondrial genome of Penaeus acehensis (Crustacea, Decapoda, Penaeidae) from Aceh province, Indonesia

Penaeid shrimps are widely distributed from Indian to western Pacific Oceans and some which are economically important. In this study, we reported full mitochondrial genome of an endemic shrimp species, Penaeus acehensis, which inhabits exclusively in the coastal water of Aceh, Indonesia. Full length of circular mitogenome of P. acehensis was 15,991 bp in length, which contained 13 protein-coding genes, 2 rRNA genes, 22 tRNA genes, and a control region. Start codons of all protein-coding genes were ATN except for COX1 in which ACG was used. Incomplete stop codon (T- -) was found in five genes including COX2, COX3, NAD5, NAD4, and NAD4L. Among its relatives, P. acehensis was most closely related to Penaeus monodon showing 89% sequence identity in its mitogenome, which was corresponding to morphological analysis. Phylogenetic tree result showed that P. acehensis was clustered together with those were distributed in Indo-West Pacific region (clade II), which is distinct from Eastern Pacific region (clade I).

Characterization of the mitogenome of Cynoglossus Senegalensis (Pleuronectiformes: Cynoglossidae)

The complete mitogenome of the Senegalese tonguesole, Cynoglossus senegalensis was determined by Illumina MiSeq platform. The complete mitochondrial genome of C. senegalensis was 16,519 bp in length. The mitochondrial genome of C. senegalensis showed a cynoglosidae-characteristic gene organization, in which translocation of control region to the position between ND1 and tRNA-Gln gene, and also inversions in tRNA-Gln gene from L-strand position to H-strand position. Phylogenetic analysis showed that C. senegalensis is most closely related to C. sinicus and S.bilineatus, which supports the previous result that genus Cynoglossidae is evolutionary paraphyletic.

The complete mitogenome of Bagrid catfish Chrysichthys nigrodigitatus (Siluriformes: Claroteidae)

We here report the complete mitochondrial genome of Chrysichthys nigrodigitatus, which is 16,514 bp in length. Mitogenome of C. nigrodigitatus showed the conserved 13 protein-coding genes, 22 tRNA genes, two rRNA genes, and two noncoding regions including the light-strand replication origin (OL) and a putative control region (CR). All tRNA genes were predicted to fold into the typical cloverleaf secondary structures with the typical base-pairing except for tRNA-Ser(AGC). Phylogenetic analysis with currently known complete mitogenome sequences in Siluriformes showed that C. nigrodigitatus is most closely related to Auchenoglanis occidentalis forming a family Claroteidae cluster.