Repository of the Department of Marine Studies at the University of Split
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Morphological and morphometric characteristics of annular seabream otoliths, Diplodus annularis (Linnaeus, 1758)
No full textU ovom radu predstavljeni su rezultati istraživanja otolita 123 jedinki vrste Diplodus annularis (Linnaeus, 1758) s područja istočnog Jadranskog mora. Analizirano je 115 adultnih jedinki s dužinskim rasponom 14,2 - 18,5 cm (16,3 ± 0,93) i 8 juvenilnih jedinki s dužinskim rasponom 2,7 - 4,1 cm (3,54 ± 0,47). Dužinsko-maseni odnos adulta opisan je jednadžbom: masa = 0,01679*dužina3,01673. Sve veze između morfometrijskih parametara otolita (dužina, širina, masa) i tijela jedinke (dužina, masa) u ovom radu opisane su linearnim modelima. Dužina otolita se, u usporedbi s masom i širinom, pokazala kao najbolji prediktor ukupne dužine i mase tijela špara kod odraslih i kod nedoraslih jedinki špara. Gledano po spolovima, situacija je gotovo identična s iznimkom kod mužjaka, gdje se širina otolita pokazala kao bolji prediktor mase tijela špara. Nadalje, analizirani su oblik i obris otolita, kod odraslih i juvenilnih jedinki, za lakšu identifikaciju vrste. Oblik otolita odraslih jedinki špara je peterokutni do ovalni, a obris je nepravilan. Otoliti nedoraslih jedinki su prilično spljošteni, njihov oblik je jako sličan otolitima riba odraslog stadija, dok je obris puno glatkiji.This thesis presents the results of a research on the otoliths of annular seabream Diplodus annularis (Linnaeus, 1758) inhabiting eastern Adriatic Sea. A total of 115 adults with a length range of 14.2 - 18.5 cm (16.3 ± 0.93) and 8 juveniles with a length range of 2.7 - 4.1 cm (3.54 ± 0.47) were analyzed. The length-weight relationship of the adults is described as: weight = 0,01679*length3,01673. All relationships between the morphometric parameters of the otoliths and the morphometric parameters of the body of annular seabream were described using a simple linear model. In comparison to otolith mass and width, the otolith length proved to be the best predictor of the total length and total weight of the annular seabream, in adults and juveniles. When divided by sex, the situation was almost identical except for males, where otolith width has been shown to be a better predictor of the total weight. Furthermore, the shape and outline of otoliths, in adults and juveniles, were analyzed for easier identification of the D. annularis species. The shape of the otolith of an adult annular seabream is pentagonal to oval, and the outline is irregular. The otoliths of juveniles are quite flattened, their shape is very similar to the otoliths of the adults, while the outline is much smoother
Comparasion of catch composition using beach seines with 12 mm and 40 mm mesh size in Hvar island area
No full textU ovom diplomskom radu napravljena je kvalitativno – kvantitativna analiza sastava ulova obalne potegače za lov gire veličine oka 12 (kontrola) i 40 mm na području otoka Hvara. Uzorkovanje okom 12 mm trajalo je od 5.2.2019. do 8.2.2019. te je napravljeno 10 potega. U ulovu je uočljiva visoka zastupljenost tri koštunjače: Spicara smaris (gira oblica), Boops boops (bukva) i Sardina plichardus (srdela), koje su po brojnosti zastupljene sa 92 % dok njihov ukupni udio u masi iznosi 88 %. Uz ove tri dominantne vrste u ulovu je zabilježena prisutnost 38 ostalih vrsta riba i glavonožaca. Uzorkovanje okom 40 mm trajalo je od 25.2.2019. do 27.2.2019. te je i u ovom slučaju napravljeno 10 potega. U samom uzorku primjećuje se dominantna zastupljenost tri koštunjače, kako u smislu brojnosti tako i u ukupnoj masi ulova: B. boops, S. smaris i M. surmuletus, koje su po brojnosti prisutne s 81,4 % u ulovu, a čine 74,4 % od ukupne mase ulova. TakoĎer u ulovu je prisutno i 36 drugih vrsta riba i glavonožaca.In this master thesis, a qualitative - quantitative analysis of the catch composition of beach seines with mesh size of 12 (control) and 40 mm in the area of the island of Hvar has been made. Sampling with the 12 mm mesh size beach seine lasted from 5.2.2019. to 8.2.2019. and 10 hauls were made. Three species of bony fish dominated the catches: Spicara smaris, Boops boops and Sardina pilchardus, which represented 92% of the total number and 88% of the total weight. In addition to these three dominant species, 38 other fish and cephalopod species were recorded in the catch. Sampling with the 40 mm mesh size beach seine lasted from 25.2.2019. to 27.2.2019. and 10 hauls were made in this case as well. The catches were dominated by three bony fish species, in terms of abundance and the total mass: B. boops, S. smaris and Mullus surmuletus, which accounted for 81.4% of the numbers and 74.4% of the total mass caught. Additionally, the catch contained 36 other species of fish and cephalopods
Utjecaj prostorne organizacije elemenata podmorskog okoliša i predatora na strukturu zajednica riba u naseljima morske cvjetnice Posidonia oceanica
No full textMarine underwater habitats dominated by seagrass Posidonia oceanica play an important role in the assembly of fish communities, affecting taxonomic and functional diversity, abundance, and fish behavior. In order to identify the relative importance of different seascape contexts of P. oceanica meadows as a habitat for fishes, fish communities associated with the seagrass P. oceanica were investigated in the Croatian Adriatic Sea, using SCUBA lure-assisted visual census. To test for the effect of predators on fish community structure, existing literature data on fish assemblages associated with P. oceanica meadows in the Mediterranean was assembled and a meta-analysis was performed. The results show: I) There is a significant effect of different arrangement of seascape elements on fish community structure -- fragmented mosaic meadows with P. oceanica growing directly on and between rocky-algal reefs had significantly higher fish abundances compared to both types of continuous meadows (bordering rock and bordering sand); and II) Total predator abundance and abundance of resident predators had a significant effect on the prey fish community -- a higher abundance of resident predator species was associated with an overall lower number of prey species. This thesis provides evidence that alternative structured habitats within close proximity to seagrass beds may affect the community structure of associated fish assemblages and that the presence of predators reduces the value of P. oceanica meadows as a refuge habitat for potential prey species. The dissertation aims at highlighting the need for the consideration of the seascape context of P. oceanica meadows in conservation management and experimental design for fish community structure while acknowledging the importance of resident predators when evaluating the relative value of this important seagrass as a habitat for the Mediterranean fish assemblages.Naselja morske cvjetnice Posidonia oceanica igraju važnu ulogu u strukturiranju zajednica riba te utječu na taksonomsku i funkcionalnu raznolikost, brojnost i ponašanje riba. Nedovoljno je poznato koji sve čimbenici utječu na strukturu zajednice riba povezanih s ovom morskom cvjetnicom. S ciljem utvrđivanja utjecaja različite prostorne organizacije elementa podmorskog okoliša na zajednice riba, proveden je vizualni cenzus uz pomoć mamca u naseljima cvjetnice P. oceanica u hrvatskom dijelu Jadranskog mora. Kako bi se ispitao utjecaj predatora na strukturu zajednica riba u naseljima morske cvjetnice P. oceanica na razini Sredozemnog mora, provedena je meta-analiza podataka u objavljenim znanstvenim radovima. Utvrđen je značajan utjecaj različite prostorne organizacije elementa podmorskog okoliša na strukturu zajednice riba – u rascjepkanim mozaičnim naseljima u kojima se P. oceanica isprepliće s kamenom podlogom obraslom makro-algama zabilježena je značajno veća brojnost riba u odnosu na kontinuirana cjelovita naselja (uz sediment ili uz kamenitu obalu). Ukupna brojnost predatora i brojnost stalno nastanjenih predatora pokazuje značajan utjecaj na zajednicu riba – povećanje brojnosti predatorskih vrsta dovodi do smanjenja broja vrsta u zajednici plijena. U radu su predstavljeni dokazi da dostupnost alternativnih strukturiranih staništa u neposrednoj blizini naselja morske cvjetnice P. oceanica utječe na strukturu zajednice riba koje u njoj žive te da prisustvo predatora smanjuje relativnu vrijednost naselja morske cvjetnice P. oceanica kao staništa za ribe koje predstavljaju potencijalni plijen. Neophodno je uzeti u obzir kontekst prostornog rasporeda elemenata podmorskog okoliša kojima dominira morska cvjetnica P. oceanica prilikom planiranja znanstvenih istraživanja, ali i kod upravljanja priobalnim područjima. Također je važno razmotriti utjecaj lokalnih, stalno nastanjenih predatora kada se procjenjuje relativni značaj naselja ove važne morske cvjetnice kao staništa za ribe na području Sredozemnog mora
Sediments and sedimentation changes in the coastal area of the eastern part of the central Adriatic
No full textU ovom su diplomskom radu predstavljeni rezultati uzorkovanja sedimenta 2019. godine u priobalnom području istočnog dijela srednjeg Jadrana. Obradom 72 uzorka sedimenta ustanovljeno je da na istraživanim postajama prevladava taloženje čestica veličine silta (42,52 ± 17,29 %), zatim slijedi glina (31,72 ± 13,78 %), pijesak (20,65 ± 21,34 %) i šljunak (4,72 ± 9,09 %). Izmjereni široki raspon veličine čestica uzrokuje vrlo lošu sortiranost sedimenta, zbog različitog podrijetla istaloženih čestica koje su najčešće karbonatne (50,70 ± 16,46% karbonata). Prema Shepardovoj klasifikaciji najzastupljeniji je bio glinoviti silt, a prema Folkovoj klasifikaciji neznatno šljunkoviti mulj. Na istraživanom području postaje se mogu izdvojiti u 3 grupe ovisno o uvjetima sedimentacije.The thesis presents results of sediment sampling during 2019 in the coastal area of the eastern part of the central Adriatic Sea. After analyses and interpretation of 72 sediment samples, it was found that at the investigated stations the deposition of silt-sized particles predominates (42.52 ± 17.29%), followed by clay (31.72 ± 13.78%), sand (20.65 ± 21.34%) and gravel (4.72 ± 9.09%). The wide range of particle sizes causes very poor sediment sorting, as a result of different sediment particles origin which are most often carbonates (50.70 ± 16.46% carbonate). According to Shepard's classification, the most common was clay silt, and according to Folk's classification, slightly gravelly mud. In the investigated area, the stations can be separated into 3 groups depending on the sedimentation conditions
Genome structure of the most important fish species in mediterranean aquaculture
No full textU ovom završnom radu predstavljene su biološke i ekološke karakteristike dviju najznačajnijih vrsta u mediteranskoj akvakulturi za koje je dostupan kvalitetan nacrt genoma, komarče Sparus aurata (Linnaeus, 1758) i lubina Dicentrarchus labrax (Linnaeus, 1758). Komarča je protandrični dvospolac što je čini zanimljivim modelom za istraživanje hermafroditizma i razvoja spolno-pristranih (SB) gena čija diferencijalna ekspresija dovodi do razvoja spolnog dimorfizma. Genom komarče se sastoji od >760 Mbp i 24 kromosoma u haploidnom setu. Uočeno je da se SB geni komarče ponašaju drugačije nego kod gonohorističnih vrsta. Jedino vrlo konzervirani ženski SB geni sa snažnom razlikom u ekspresiji brže evoluiraju od ostalih gena. Navedena činjenica se potencijalno dovodi u vezu sa smanjenom efektivnom veličinom populacije ženki i smanjenom purificirajućom selekcijom. Kod lubina je posebno zanimljiva njegova eurihalinost te je u genomu identificirano nekoliko genskih obitelji s ulogom u osmoregulaciji i membrasnkom transportu (klaudini, akvaporini, prolaktini). Genom lubina je veličinom nešto manji od genoma komarče i također ima 24 kromosoma. Analizom nukleotidne raznolikosti na razini čitavog genoma su uočeni zanimljivi heterogeni obrasci diferencijacije i smanjene rekombinacije za koje se smatra da su rezultat erozije divergencije i nejednolike introgresije uslijed sekundarnog kontakta nakon dugog perioda alopatrijske izolacije.In this dissertation, the biological and ecological characteristics of the two most important species in Mediterranean aquaculture are presented, for which a quality genome draft is available, gilthead sea bream Sparus aurata (Linnaeus, 1758) and European seabass Dicentrarchus labrax (Linnaeus, 1758). Gilthead sea bream is a protandrous species and an interesting model for the study of hermaphroditism and sex-biased (SB) genes development whose differential expression leads to the development of sexual dimorphism. The gilthead sea bream genome consists of 760 Mbp and 24 chromosomes in a haploid cell. It has been observed that sex-biased genes of gilthead sea bream behave differently than in gonochoristic species and that only highly conserved female sex-biased genes with a strong difference in expression evolve faster than non-biased genes. This fact is potentially linked to reduced effective size of the famle population and relaxed purifying selection. European seabass is a euryhaline species and several gene families with a role in osmoregulation and membrane transport (claudins, aquaporins, prolactins) have been identified in its genome. Seabass genome is slightly smaller than the glithead sea bream genome and also has 24 chromosomes. The analysis of nucleotide diversity at the whole-geome level revealed interesting heterogeneous patterns of differentiation and reduced recombination, possibly resulting from erosion of divergence and uneven introgression due to secondary contact after a long period of allopatric isolation
Survival of Anisakis spp. parasite in seafood products and possible implications on human health
No full textAnisakis (Dujardin, 1845) (Nematoda, Anisakidae) je rod nametnika iz koljena oblića čiji životni ciklus uključuje beskralješnjake, ribe (sporadično i glavonošce) i morske sisavce. U ovom radu opisana je morfologija, razmnožavanje i životni ciklus nametnika Anisakis spp. s posebnim osvrtom na preživljavanje nametnika u gotovim proizvodima. Proučavajući distribuciju i prevalenciju Anisakis spp. može se zaključiti da je ovaj nametnik prisutan u gotovo svim komercijalnim vrstama riba Jadrana. Ličinke Anisakis spp. izolirane su iz vrsta riba poput inćuna, tune, oslića, šaruna, plavice ili skuše te iz lignjuna. Proizvodi ribarstva koji se pripremaju od navedenih vrsta riba najčešće se jedu nedovoljno termički obrađeni ili konzervirani postupkom koje ne osigurava uništenje nametnika, poput hladnog mariniranja što predstavlja veliku opasnost po zdravlje ljudi. Zakonski akti nalažu kako postupati s proizvodima ribarstva odmah po ulovu i tijekom prerade što smanjuje kasnije moguće fatalne posljedice. Tradicionalne recepture koje se pripremaju u ugostiteljstvu ili kod kuće, a tijekom kojih se zakonske odredbe ne provode mogu dovesti do prodiranja ličinki trećeg stadija ovog oblića kroz zid probavnog sustava čovjeka te svojim prisustvom izazvati patološke učinke kod ljudi i izazvati bolest koja se naziva se anisakijaza.Anisakis (Dujardin, 1845) (Nematodae, Anisakidae) is a genus of parasitic nematodes whose lifecycle involves fish and marine mammals. This thesis describes the morphology, reproduction and life cycle of the parasite Anisakis spp. with special reference to the survival of parasites in ready-to-eat products. The distribution and prevalence of Anisakis spp. is high in almost all commercially important fish species of the Adriatic Sea. Anisakis spp. larvae were isolated from fish species such as anchovies, hake, blue whiting, tuna or mackerel, and from squid. Fishery products prepared from these fish are commonly eaten raw or without sufficient thermal treatment or preserved by a technological process that does not ensure the destruction of the parasites, such as cold marinating or smoking. These products present a serious hazard for human health. To avoid the possible fatal consequences, the legislation suggests practices for onboard fishery products handling, manipulation of fish after the catch and throughout processing. It is important to follow these measures also in food catering and at home during the preparation of traditional recipes that lack sufficient thermal treatment since the penetration of the third stage larvae of this parasite through the stomach/intestine wall of the human digestive system causes a disease called anisakiasis
Octopods of the Northern and Central Adriatic Sea
No full textU ovom diplomskom radu opisani su nalazi vrsta iz reda Octopoda na području sjevernog i srednjeg Jadrana prikupljeni tijekom ekspedicija MEDITS u razdoblju od 1996. do 2019. godine. Za nađene vrste prikazana je dubinska i prostorna raspodjela, indeksi biomase i brojnosti te omjeri spolova i udjeli pojedinih stupnjeva zrelosti gonada. Tijekom navedenih istraživanja nađeno je ukupno osam vrsta iz ovog reda. Sve nađene vrste već su zabilježene u Jadranskom moru te su, osim triju gospodarski značajnih vrsta (Octopus vulgaris, Eledone cirrhosa i Eledone moschata), ostale vrste rijetko lovljene. Tako su npr. vrste Pteroctopus tetracirrhus i Macrotritopus deffilippii zabilježene sa svega nekoliko primjeraka u cijelom razdoblju istraživanja. Vrste Octopus vulgaris i Eledone moschata lovljene su samo na području kontinentalne podine, dok su vrste Eledone cirrhosa, Octopus macropus, Pteroctopus tetracirrhus i Scaeurgus unicirrhus nađene i na dubinama većim od 200 m. Od svih oktopoda jedino je vrsta Octopus salutii zabilježena na dubinama većim od 400 m.This thesis describes the findings of species of the order Octopoda in the Northern and Central Adriatic Sea collected during the MEDITS expeditions in the period from 1996 to 2019. For all found species, depth and spatial distribution, biomass and abundance indices, sex ratios and proportions of gonad maturity stages were presented. During these studies, a total of eight species from this order were found. All species have already been recorded in the Adriatic Sea, and apart from three economically significant species (Octopus vulgaris, Eledone cirrhosa, Eledone moschata), others have rarely been found. For example, species Pteroctopus tetracirrhus and Macrotritopus deffilippii were recorded with only a few specimens throughout the study period. Octopus vulgaris and Eledone moschata species were found only on the continental shelf, while Eledone cirrhosa, Octopus macropus, Pteroctopus tetracirrhus and Scaeurgus unicirrhus were also found at depths greater than 200 m. Of all octopuses only the species Octopus salutii was recorded at depths greater than 400 m
Biohydrogen production from microalgae
No full textZbog ograničenih zaliha i doprinosa akumulaciji ugljikovog dioksida u okolišu kontinuirana upotreba fosilnih goriva smatra se neodrživom. Za ekonomsku i ekološku održivost ljudskoj vrsti je potrebno obnovljivo gorivo. Mikroalge predstavljaju vrijednu sirovinu za proizvodnju prehrambenih, farmaceutskih i kozmetičkih proizvoda (vitamina, antioksidansa, bjelančevina, masnih kiselina, pigmenata, imuno stimulansa i lijekova) te proizvodnju biogoriva. Učinkovita proizvodnja biovodika iz mikroalgi povezana je s odabirom vrste, odgovarajuće hranjive podloge, uvjeta i postupaka vođenja bioprocesa u bioreaktorskim sustavima, metodama izdvajanja vodika i počišćivanja biomase, odnosno lipida iz biomase mikroalgi. U radu je opisana proizvodnja biovodika iz mikroalgi i njihova praktična primjena.Continued use of fossil fuels has been recognized as unsustainable because of exhausting stocks and their contribution to the accumulation of carbon dioxide in the environment. For economic and environmental sustainability human race needs a renewable, CO2 neutral transportation fuel. Microalgal biomass represents valuable raw material for food, pharmaceuticals, and the cosmetic industry (vitamins, antioxidants, proteins, fatty acids, pigments, immunostimulants, and pharmaceuticals) as well as for biofuels production. The efficient production of biohydrogen from microalgae biomass is associated with a selection of microalgae, an appropriate culture medium, conditions, and procedures of keeping the bioprocess bioreactor systems, biomass and lipids separation and purification methods. This thesis comprehends biohydrogen production and practical application of microalgal biomass
Marine invertebrate cell culture
No full textKulture životinjskih stanica su značajan alat u staničnoj i molekularnoj biologiji budući pružaju izvrsne modele sustava za proučavanje fiziologije i biokemije stanica, procesa mutageneze i karcinogeneze te učinka lijekova i toksičnih spojeva na stanice. U ovom radu je dan pregled dosadašnjih saznanja na području staničnih kultura morskih beskralježnjaka. Kulture matičnih i embrionalnih stanica ovih organizama predstavljaju novi eksperimentalni model koji karakteriziraju visoka razina fizioloških i sintetskih procesa. Primarne kulture morskih beskralježnjaka koje su dosada uspješno kultivirane su: epitelne stanice spužvi, rakova, bodljikaša, plaštenjaka i svitkoglavaca; neuroni žarnjaka, rakova i mekušaca; krvne stanice rakova, mekušaca i plaštenjaka te embrionalne stanice spužvi, žarnjaka i bodljikaša. Nažalost, još nije uspostavljena stanična linija nekog morskog beskralježnjaka, što ukazuje na nedostatak informacija o potrebama njihovih stanica (pH, nutrijenti, temperatura, supstrat) u in vitro uvjetima.Animal cell cultures are important tool in cell and molecular biology that provides an excellent model systems for studying cell physiology and biochemistry, the processes of mutagenesis and carcinogenesis, as well as the effects of drugs and toxic compounds on cells. This paper provides an overview of current knowledge in the field of marine invertebrate cell cultures. The stem and embryonic cell cultures of these organisms represent new experimental model characterized by a high variety of physiological and synthetic processes. The primary cultures of marine invertebrates that have been successfully cultivated are: epithelial cells of spongia, crustacea, echinodermata, tunicata and cephalochordata; neurons of cnidaria, crustacea and mollusca; blood cells of crustacea, mollusca and tunicata, and embryonic cells of spongia, cnidaria and echinodermata. Unfortunately, a cell line of a marine invertebrate has not yet been established, indicating the lack of information about their cells requirements (pH, nutrients, temperature, substrate) when grown in vitro
Determination of antimicrobial activity of spices using well diffusion method
No full textZačinsko bilje radi svog kemijskog sastava i sadržaja biološki aktivnih spojeva ima vrlo pogodan učinak na zdravlje čovjeka pa je i interes za njegovu moguću primjenu u poboljšanju sigurnosti hrane povećan. Fenolni spojevi su sekundarni metaboliti biljka koji imaju ulogu u obrani biljke od vanjskih utjecaja, a upravo njima se prepisuju antioksidativna i antimikrobna svojstva. U ovom radu analiziran je sadržaj ukupnih fenola 17 odabranih začinskih biljaka te im je određena antimikrobna aktivnost. U tu svrhu pripremljeni su UVZ/vodeni ekstrakti i određen antimikrobni učinak na četiri patogene bakterije, dvije Gram pozitivne (Staphylococcus aureus, Listeria monocytogenes) i dvije Gram negativne (Salmonella enterica i Escherichia coli). Za određivanje antimikrobnog potencijala korištene su dvije metode: metoda difuzije u jažicama i minimalne inhibitorne koncentracije (MIC). Korelacija između sadržaja ukupnih fenola i antimikrobne aktivnosti 17 začinskih biljaka nije utvrđena, a najbolje rezultate pokazao je ekstrakt češnjaka (MIC=17,94 mg GAE/L, zona inhibicije >25mm) koji je imao sadržaj ukupnih fenola od 179,44 mg GAE/L. Ostali ekstrakti koji su pokazali antimikrobnu aktivnost bili su: klinčić, kadulja, koromač, limun, maslina, ružmarin, peršin, celer.The chemical structure and content of biologically active compounds fromspices have a beneficial effect on human health, thus the interest of thier possible application in improvement of food safety has increased. Phenolic compounds are secondary metabolites of plantsthat play a protection role from extrinsic factors and show the antioxidant and antimicrobial properties. In this theses the content of total phenols of extractsfrom 17 selected spices was analyzed and their antimicrobial activity was determined. For this purpose, UVZ/aqueous extracts were prepared and antimicrobial potentian on four pathogenic bacteria, two Gram positive (Staphylococcus aureus, Listeria monocytogenes) and two Gram negative (Salmonella enterica, Escherichia coli) was determined using two methods: well diffusion method and the minimum inhibitory concentration method (MIC).No correlation was found between total phenols content and antimicrobial activity of 17 spices, garlic extract (MIC = 17.94 mg GAE/L, inhibition zone>25 mm) was found to have the best results, which had a total phenol content of 179.44 mg GAE/L. Other extracts that showed antimicrobial activity were: clove, sage, fennel, lemon, olive, rosemary, parsley, celery