Repository of the Department of Marine Studies at the University of Split
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Cnidarian immunity
No full textImunosni sustav je ključan za obranu svakog organizma od patogenih organizama, ozljeda i abnormalnih staničnih procesa. Žarnjaci su veoma raznoliko koljeno životinja koje nemaju razvijen stečeni imunitet, ali se oslanjaju na urođeni imunitet i razvili su složene i veoma učinkovite procese obrane i zaštite od štetnih mikroorganizama. Prva linija obrane su receptori prepoznavanja uzorka (PRR) koji imaju mogućnost imunosnog prepoznavanja, a najpoznatiji su TLR receptori, NOD receptori i lektini. Ti proteini aktiviraju imuno-signalni module žarnjaka poput TLR puta i puta aktivacije sinteze melanina te puta komplementa koji su ključni prilikom procesa poput inkapsulacije patogena, razgradnje i zacjeljivanja rana. Krajnje točke ovih signalnih kaskada su imunosni efektori, molekule i proteini čija je glavna zadaća uništavanje patogena. Postoji nekoliko efektorskih odgovora kod žarnjaka, a oni uključuju površinski sloj sluzi, antimikrobne peptide, reaktivne kisikove radikale te cirkulirajuću populaciju amebocita. Bitna komponenta imuniteta žarnjaka je i epitel koji služi kao imunosna prepreka. Epitel je stanište mikrobnim zajednicama i simbiontima koji su također dio imunosnog sustava te su od esencijalne važnosti za zdravlje jedinke. U ovom radu je pobliže opisan imunitet žarnjaka uključujući složene reakcije koje se odvijaju u trenutku kada jedinka dođe u doticaj s patogenom i način na koji dolazi do njihovog izoliranja te uništavanja.The immune system is crucial for every organism's defence against pathogenic organisms, injuries and abnormal cellular processes.. Cnidarians are a very diverse phylum of animals without developed adaptive immunity, but rely on innate immunity and have developed complex and very effective defense and protection mechanisms against harmful microorganisms. The first line of defence present pattern recognition receptors (PRR) essential for immune recognition, and the best known are TLR receptors, NOD receptors and lectins. These proteins activate the immune signaling modules such as the TLR pathway, the melanin synthesis pathway and complement pathway, which are crucial in processes such as pathogen encapsulation, lysis and wound healing. The endpoints of these signaling cascades are immune effectors, molecules and proteins whose main task is to destroy pathogens. There are several effector responses in cnidarians, and they include the mucosal surface layer, antimicrobial peptides, reactive oxygen species and circulating population of amoebocytes. An important component of cnidarian immunity is the epithelium, which serves as an immune barrier. The epithelium is a habitat for microbial communities and symbionts that are considered important part od the immune system and are essential for the health of an individual organism. This thesis describes in more detail the immunity of cnidarians, including the complex reactions initiated upon the contact with the pathogen and the way in which intruders are isolated and destroyed
Distribution of Hermodice carunculata in aquatorium of Vis
No full textU današnje vrijeme klimatske promjene imaju sve veći utjecaj na ekosustave te se najprije očituju u porastu temperature zraka i mora. Vrsta Hermodice carunuclata pokazuje sposobnost prilagodbe na porast temperature mora te se zadnjih nekoliko godina intenzivno istražuje utjecaj ove vrste na druge bentoske vrste. Obzirom na sve veću prostornu rasprostranjenost može se vidjeti na većim dubinama i u plitkim vodama gdje stvara nelagodu kupačima zbog mogućih ozljeda pri izravnom kontaktu. U ovom radu prikazani su podaci prikupljeni na 12 lokacija na području otoka Visa o dubini, temperaturi i broju jedinki ove vrste. Pomoću navedenih podataka prikazane su korelacije broja jedinki u odnosu na dubinu i temperaturu. Analizom podataka ustanovljena je široka rasprostranjenost vrste u akvatoriju Visa. Budući da je riječ o iznimno tolerantoj vrsti koja ima invazivni potencijal na biocenoze i bentoske organizme važno je pratiti njezino širenje i daljnji utjecaj na istraživanom području.Nowadays, climate change has an increasing impact on ecosystems and it is manifests first in rising air and sea temperatures. The species Hermodice carunuclata shows the ability to adapt to rising sea temperatures, and the impact of this species on other benthic species has been intensively investigated in recent years. Due to the increasing spatial distribution, it can be seen at greater depths and in shallow waters, where it creates discomfort for bathers due to possible injuries in direct contact. This paper presents data collected at 12 locations on the island of Vis, where data on the depth, temperature and number of organisms at each location were collected. Using the above data, the relationship between the number of organisms and depth and temperature is shown. The analysis of the data showed a wide distribution of the species in the waters of Vis. Since it is an extremely tolerant species that has an invasive potential on biocenoses and benthic organisms, it is important to monitor the spread of this species and its possible further impact in this area
Model calculation and break-even analysis of sea bass production
No full textCilj rada bio je utvrditi razinu proizvodnje lubina kod koje su pokriveni ukupni troškovi uz
determiniranu prodajnu cijenu i ekonomsku efikasnost kaveznog uzgoja lubina. U radu su
korištene metode kalkulacije pokrića varijabilnih troškova, analiza točke pokrića i izračun
temeljnih mjerila poslovne uspješnosti. Pozitivan poslovni rezultat i vrijednosti temeljnih
mjerila poslovne uspješnosti u analiziranom modelu pokazuju da je kavezni uzgoj lubina
efikasan, pod pretpostavkom postizanja očekivane količine proizvodnje uz 10% mortalitet i
uspješne prodaje.The goal of this work was to determine level of sea bass production in which total costs are
covered with already determined sale price and economic efficiency of sea bass production.
Methods used in this work include model of gross margin calculation, break-even point analysis
and calculation of basic measures of business performance. The positive business result and the
values of basic measures of business performance in analysed model show that the sea bass
production is efficient, under the assumption of achieving the expected amount of production
including 10% mortality rate and the successful sale
DISTRIBUTION OF HERMODICE CARUNCULATA IN THE WATERS OF THE ISLAND OF BRAČ
No full textVrsta Hermodice carunculata termofilni je grabežljivac koji je posljednjih godina proširio areal rasprostranjenosti u Sredozemnom i Jadranskom moru, gdje se često može susresti u većim skupinama. Zbog toga je cilj ovog diplomskog rada bio prikazati stanje populacije ove vrste na istočnoj strani srednjeg Jadrana te posebno u arhipelagu otoka Brača. U radu su prikazani podaci o prisutnosti H. carunculata na hrvatskoj obali srednjeg Jadrana, te posebno podaci prikupljeni na području otoka Brača, kao i jednog dijela otoka Hvara i Šolte. Analizom podataka prikupljenih na hrvastkoj obali srednjeg Jadrana u 2019. godini, od ukupno 93 lokacije na kojima su prikupljeni podaci, na njih 91 uočeno je prisustvo vrste H. carunculata. Na otoku Braču prisustvo vrste je dominiralo s južne strane otoka, kao što je i slučaj na otoku Šolti, dok su na Hvaru zabilježene tek dvije lokacije sa sjeverne strane otoka. Naknadnim praćenjem promjena u distribuciji navedene vrste u istraživanom području, moglo bi se procijeniti kakav bi utjecaj ova vrsta mogla imati na bentoske zajednice.The species Hermodice carunculata is a thermophilic predator that has expanded its range in recent years in the Mediterranean and in the Adriatic Sea, where it can often be found in larger groups. Therefore, the aim of this thesis was to investigate the state of the population of this species on the eastern side of the Central Adriatic and especially in the waters of the island of Brač. The paper presents data on the presence of H. carunculata on the Croatian coast of the Central Adriatic, and especially data collected on the island of Brač, and in one part of the islands Hvar and Šolta. The analysis of data collected along the Croatian coast in the Central Adriatic in 2019, from 93 locations where data were collected, the presence of H. carunculata was observed in 91 of them. On the island of Brač, the presence of the species dominated on the southern side of the island, as is the case on the island of Šolta, while on Hvar island only two locations were recorded on the northern side of the island. With the subsequent monitoring of changes in distribution of this species the impact of this species on benthic communities in this area could be assessed
Appetite control in fish
No full textU ovom završnom radu je analizirana kontrola apetita kod riba. Na apetit kod riba utječu mnogobrojni čimbenici, a u radu je najveći fokus stavljen na fiziološku kontrolu apetita, gdje veliku ulogu ima hormonalna regulacija apetita riba. Poznavanje načina hranjenja i kontrolira hranjenja je od velike važnosti u akvakulturi. Naime tijekom uzgojnog ciklusa riba trošak koji se izdvaja za hranu predstavlja najznačajniju financijsku stavku. Stoga kontrola apetita kod riba omogućava uzgajivačima lakše uzgajanje određene vrste uz najmanje troškove.In this final thesis, appetite control in fish is analyzed. Appetite in fish is influenced by many factors, and in this thesis main focuse is placed on the physiological control of appetite, where the hormonal regulation of fish appetite plays a major role. Knowing how to feed and control feeding is of great importance in aquaculture. Namely, during the fish farming cycle, the cost allocated for food is the most important financial item. Therefore, appetite control in fish makes it easier for breeders to breed a particular species at the lowest cost.
(25 pages, 7 figures, 30 references, original in: Croatian)
Keywords: appetite, fish, physiological control, hormonal regulatio
Composition and categorization of Norway lobster creel catches near Klenovica
No full textU ovom radu analiziran je sastav ulova vrša za lov škampa, Nephrops norvegicus, na području Klenovice (ribolovna zona E, sjeveroistočni Jadran). Istraživanje je provedeno u razdoblju od 19. ožujka do 8. svibnja 2020. godine. Analiziran je kvalitativno-kvantitativni sastav lovine iz 3000 komercijalnih vrša izrađenih od mrežnog tega veličine 36 mm. Tijekom 10 ribolovnih dana ukupno je ulovljeno 9392 jedinke 9 različitih vrsta organizama. Od rakova su u ulovu dominirali rak loptaš Liocarcinus depurator i škamp N. norvegicus, a od ribljih vrsta tragalj Spicara maena. Unatoč tome što je 5 jedinki škampa zabilježeno ispod minimalne referentne veličine za očuvanje (MRVO = 2 cm CL), ipak je zabilježeno odbacivanje ulova škampa i iznad te veličine. Prosječna dužina karapaksa (CL) kod koje je jedinka škampa imala jednaku šansu da bude odbačena ili zadržana iznosila je 3 cm. Tijekom istraživanja ribar je škampe sortirao u dvije dužinske kategorije, i to „mali“ i veliki“ škamp. Dužinski raspon „malih“ škampa kretao se od 3 do 3,9 cm CL, a „velikih“ od 4 do 5,7 cm CL. Prosječna dužina kod koje je jedinka škampaIn this thesis catch composition of creels targeting Norway lobster, Nephrops norvegicus, in the area of Klenovica (fishing zone E, Northeast Adriatic) was analysed. Samples were collected during ten fishing days in period from March 19th to May 8th 2020. In total 3000 creels were analysed. Commercial creels mounted with square mesh netting of 36 mm were used. In total, 9392 individuals belonging to 9 different species were caught. Harbour crab, Liocarcinus depurator, and Norway lobster, N. norvegicus, were the most abundant crabs in catches, while, blotched picarel, Spicara maena, was the most dominant fish species. Despite the fact that 5 individuals of Norway lobster caught with creels were below minimum conservation reference size (MCRS = 2 cm CL), discarding did occur. The average carapace length (CL) at which an individual of Norway lobster had equal chance of being discarded or retained was 3 cm. All retained Norway lobsters were sorted in two length categories, “small” and “large”. The length of “small” Norway lobster ranged from 3 to 3.9 cm CL, and of “large” from 4 to 5.7 cm CL. The average length of individual Norway lobster which had an equal chance of being categorized as “small” or “large” was 4.1 cm CL
Morphology of jaws and gills of sparus aurata linnaeus, 1758 and dicentrarchus labrax (Linnaeus, 1758) from the aquaculture
No full textU ovom su diplomskom radu analizirana morfološka i morfometrijska obilježja čeljusti i škrga za dvije vrste iz uzgoja, i to za oradu, Sparus aurata i lubina, Dicentrarchus labrax. Ukupna dužina tijela svih analiziranih jedinki vrste S. aurata se nalazila u rasponu od 22,5 do 29,5 cm, s prosječnom dužinom od 26,20 ± 1,77 cm. Ukupna dužina tijela svih analiziranih jedinki vrste D. labrax je bila u rasponu od 22,5 do 34,5 cm, s prosječnom dužinom od 30,75 ± 2,70 cm. Zubi orade i lubina su smješteni na gornjoj i donjoj čeljusti. Zubi orade su u pravilu okrugli i tupi, a zubi lubina šiljasti. Njihova veličina (opseg i površina kod oradi i dužina kod lubina) je u linearnom odnosu s dužinom ribe. Škržni listići orade bili su resaste strukture, dok su škržni nastavci bili mali i vidljivi samo na prvom škržnom luku. Škrge lubina također imaju škržne listiće resaste strukture te se škržni nastavci također vide samo na prvom škržnom luku, ali su za razliku od onih kod orade puno veći. Prosječna dužina donjeg dijela škržnih lukova je bila veća od dužine gornjeg dijela škržnih lukova i za lubina i za komarču. Navedene dužine su bile u linearnom odnosu s dužinom ribe.In this thesis, we analysed the morphological and morphometric characteristics of jaws and gills for two species from the aquaculture, namely for the sea bream, Sparus aurata and the sea bass, Dicentrarchus labrax. The total body length of all analysed S. aurata individuals ranged from 22.5 to 29.5 cm, with an average length of 26.20 ± 1.77 cm. The total body length of all analysed D. labrax individuals ranged from 22.5 to 34.5 cm, with an average length of 30.75 ± 2.70 cm. The sea bream and the sea bass teeth are located on the upper and lower jaws. The sea bream teeth are usually round and blunt, while the sea bass teeth are pointed. Their size (area and perimeter in the sea bream and length in the sea bass) is in a linear relationship with the length of the fish. Gill filaments of the sea bream had fringed structures, while gill rakers were small and visible only on the first gill arch. The gills of the sea bass also have fringed structured gill filaments and the gill rakers are also visible only on the first gill arch, but unlike those of the sea bream they are much larger. The average length of the lower part of the gill arches was greater than the length of the upper part of the gill arches for both sea bass and sea bream. The mentioned lengths were in a linear relationship with the length of the fish
Marine ecosystem modeling
No full textEkološki modeli su pojednostavljeni prikazi stvarnog ekosustava, koji se koriste da unaprijede
naše razumijevanje ekoloških odnosa i procesa kao i za prognozu njihove dinamike. Najčešće
se radi o matematičkom prikazu sustava i s obzirom na kompleksnost kreću se od jednostavnih
analitičkih modela pa do kompliciranih realističnih prognostičkih sustava. Ekološki modeli
imaju široku primjenu i koriste se u znanstvenim istraživanjima, procjenama rizika, zaštiti
okoliša, poljoprivredi i nizu drugih djelatnosti. U ovom radu su prikazani rezultati operativnog
hidrodinamičkog i biogeokemijskog modela koji su dio Copernicus sustava. Prikazane su i
analizirane promjene vrijednosti različitih fizikalnih i ekoloških parametara kroz period od
mjesec dana na dubinama od 1, 50 i 100 m. Odabrane su tri točke u Jadranu (sjeverni, srednji i
južni) i u svakoj od tih točaka prikazana je vertikalna razdioba modeliranih fizikalnih i
ekoloških varijabli, kao i njihove vremenske promjene od 15. 8. do 15. 9. 2020. Modelirani
fizikalni parametri su u skladu s klimatološkim vrijednostima u Jadranu za prijelazno razdoblje
od ljeta do jeseni te se može zaključiti da model uspješno reproducira fiziku Jadrana. Za daljnju
potvrdu uspješnosti modela bilo bi potrebno usporediti rezultate modela s odgovarajućim in situ
i satelitskim podacima. Slično je i za biogeokemijske parametre.Ecological models are simplified representations of the real ecosystem, which are used to
improve our understanding of ecological relationships and processes as well as to predict their
dynamics. It is most often a mathematical representation of the system and, according to their
complexity, they range from simple analytical models to complicated realistic prognostic
systems. Ecological models have a wide application and are used in scientific research, risk
assessments, environmental protection, agriculture and a number of other activities. This thesis
presents the results of an operational hydrodynamic and biogeochemical model that are part of
the Copernicus system. Changes in the values of various physical and ecological parameters
over a period of one month at depths of 1, 50 and 100 m are presented and analyzed. Three
points in the Adriatic (northern, middle and southern) were selected and in each of these points
the vertical distribution of modeled physical and ecological variables is shown, as well as their
time changes from 15th August to 15th September 2020. The modeled physical parameters are
in accordance with the climatological values in the Adriatic for the transition period from
summer to autumn, and it can be concluded that the model successfully reproduces the physics
of the Adriatic. To further confirm the success of the model, it would be necessary to compare
the results of the model with the corresponding in situ and satellite data. It is similar for
biogeochemical parameters
Process of regeneration in cephalopods
No full textOzljede kože, krakova i plašta česte su kod glavonožaca zbog njihova predatorskog načina života, a često nastaju i prilikom parenja. Nakon ozljede, oštećene strukture mogu zacijeliti i vratiti svoju funkciju zahvaljujući sposobnosti regeneracije koje ove životinje posjeduju. Proces regeneracije je podijeljen u tri faze: zacjeljivanje rane, degeneracija tkiva i obnova tkiva. U ovom radu su opisani ključni morfološki, citološki i histološki procesi koji se odvijaju tijekom regeneracije tkiva kod glavonožaca. Nadalje, navedene su osnovne karakteristike mišićnog, živčanog i krvožilnog sustava te je dat pregled dijelova tijela koji imaju sposobnost regeneracije, i to: koža, krakovi, tentakuli i palijalni živac.Injuries to the skin, arms and mantle are common in cephalopods due to their predatory lifestyle, and often occur during mating. After injury, damaged structures can heal and regain their function by virtue of regenerative abilities these animals possess. The regeneration process is divided into three phases: wound healing, tissue degeneration, and tissue regeneration. This paper describes the key morphological, cytological and histological processes that take place during tissue regeneration in cephalopods. Furthermore, the basic characteristics of the muscular, nervous and vascular system and an overview of the parts of the body that have the ability to regenerate are given, namely: skin, arms, tentacles and pallial nerve
Capture and conditioning of common octopus broodstock (Octopus vulgaris, Cuvier 1797) for the purpose of repopulation
No full textU ovom radu analizirani su glavni čimbenici koji su potrebni za prikupljanje i održavanje matičnog jata hobotnice (Octopus vulgaris). Održavanje se temelji na ribolovu nedoraslih jedinki i njihovog uzgoja u zatočeništvu. Drugi dio predmetnog istraživanja se odnosio na mogućnost repopulacije O. vulgaris. Istraživanjem su obuhvaćena dva matična jata, prvo matično jato je sakupljeno 2019. a drugo tijekom 2020. godine. Prikupljanje živih hobotnica se obavljalo u akvatoriju s južne strane otoka Brača: u uvalama Smrka i Lučice te uz obale Rta Kobila. Matična jata hranjena su sitnom plavom ribom (Sardina pilchardus i Engraulis encrasicolus), a tijekom šezdesetodnevnog istraživanja konstantno su praćeni zootehnički parametri. Rezultati rasta i iskoristivosti hrane prikazani su kroz parametre: prirast mase (BWI) 110,62 ± 31,67%, specifična stopa rasta (SGR) 1,22 ± 0,25%, apsolutna stopa rasta (AGR) 9,70 ± 1,68 grama, apsolutna stopa ishrane (AFR) 20,54 ± 1,61 grama, specifična stopa ishrane (SFR) 2,51 ± 0,53% i efikasnost hranjenja (FE) 38,28 ± 9,34%. Nakon uspješne kopulacije u 2019. godini tri ženke su početkom lipnja polagale oplođena jaja. Paraličinke su hranjene ranim razvojnim stadijima (zoa) raka žbirca (Eriphia verrucosa) 10 dana, nakon čega su puštene u more u blizini Instituta za oceanografiju i ribarstvo u Splitu. Prosječna apsolutna plodnost za tri uspješno oplođene ženke iznosila je 302 612 ± 15,80. Šest mjeseci nakon puštanja prikupljene su 23 jedinke s ciljem testiranja srodnosti s maticama i provjere uspješnosti repopulacije. U predmetnoj studiji, kod ulovljenih potencijalnih potomaka matičnog jata od 23 jedinke dvije su prepoznate (19F1_O_09 i 19F1_0_12). Kao par roditelja prepoznate su jedinke 19F06 i 19M10.In this paper the main factors necessary for capturing and conditioning of common octopus
broodstock Octopus vulgaris were analyzed. Conditioning is based on catching of juveniles and
their cultivation in captivity. Second part of the research examines the possibility of O. vulgaris
repopulation. In the research two broodstocks of the common octopus were included, first one
was captured in 2019, and second one was captured in 2020. The collecting of a live samples
was done at the south side aquatory of the island Brač in cove Smrka, Lučice and cape Kobila.
The broodstockes were fed with small pelagic fish (Sardina pilchardus i Engraulis
encrasicolus), and through 60 days of research zootechnical parameters were continuously
monitored. The results of growth and diet were represented through parameters: body weight
increase (BWI) 110.62 ± 31.67%, specific growth rate (SGR) 1.22 ± 0.25%, absolute growth
rate (AGR) 9.70 ± 1.68 grams, absolute feeding rate (AFR) 20.54 ± 1.61 grams, specific feeding
rate (SFR) 2.51 ± 0.53% and feed efficiency (FE) 38.28 ± 9.34%. In June 2019 after successful
copulation, three females laid their eggs. For 10 days paralarvae were fed with zoa of crab
(Eriphia verrucosa), after wich they were released in front of Institute of Oceanography and
Fisheries in Split. Fecundity for three females was 302 612 ± 15.80. Six months after releasing,
23 octopuses were captured to verify the success of repopulation and DNA test. In the sampled
stock of 23 individuals, two were recognized (19F1_O_09 and 19F1_0_12) coming from the
couple of parents (19F06 i 19M10)