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Significance and application of mycorrhiza in strengthening resistance to pathogens
No full textMikorizne gljive predstavljaju ključne partnere biljaka u tlu, ulazeći u mutualističke simbioze koje značajno poboljšavaju rast i zdravlje biljaka. Mikoriza je mutualistička simbioza između gljiva i korijena biljaka koja omogućuje bolji pristup hranjivim tvarima te vodi. Povijesno gledano, ovaj fenomen je prepoznat još krajem 19. stoljeća, a danas je od ključne važnosti za održivu poljoprivredu. Mikorizne gljive apsorbiraju mineralne hranjive tvari iz tla i prenose ih u biljke, dok zauzvrat dobivaju ugljikohidrate proizvedene fotosintezom. Postoji nekoliko tipova mikorize, uključujući arbuskularne, ektomikorize i erikoidne mikorize, svaka s različitim karakteristikama i ulogama u ekosustavu.
Iznimno je važna i uloga mikoriznih gljiva u održavanju ekosustava. One poboljšavaju strukturu tla, povećavaju bioraznolikost, stabiliziraju ekosustave te pomažu biljkama da se prilagode različitim uvjetima okoliša. Gljive koloniziraju korijenje biljaka putem spora ili hifa, formirajući specifične strukture za razmjenu hranjivih tvari. Biljke luče ugljikohidrate koje gljive koriste kao izvor energije, dok gljive apsorbiraju mineralne hranjive tvari iz tla i transportiraju ih do biljaka. Mikorizne gljive povećavaju apsorpciju hranjivih tvari, luče hormone rasta i enzime te štite biljke od teških metala i soli. Povećana apsorpcija hranjivih tvari posebno je važna za fosfor i dušik – ključne makroelemente za rast biljaka.
Ujedno, mikorizne gljive induciraju brojne promjene u fiziologiji biljaka koje rezultiraju jačanjem i aktivacijom njihovih obrambenih mehanizama. Aktivacija obrambenih mehanizama uključuje proizvodnju fitoaleksina, jačanje staničnih stijenki i aktivaciju obrambenih gena, što povećava otpornost biljaka na patogene. Cilj ovog rada je istražiti širok spektar korisnih učinaka mikoriznih gljiva, posebno u kontekstu njihove uloge u apsorpciji hranjivih tvari, lučenju hormona rasta i enzima, zaštiti od teških metala i soli te jačanju otpornosti biljaka na patogene.Mycorrhizal fungi represent crucial partners for plants in the soil, entering into mutualistic symbioses that significantly enhance plant growth and health. Mycorrhiza is a mutualistic symbiosis between fungi and plant roots, enabling better access to nutrients and water. Historically, this phenomenon was recognized in the late 19th century and is now of key importance for sustainable agriculture. Mycorrhizal fungi absorb mineral nutrients from the soil and transfer them to plants while receiving carbohydrates produced by photosynthesis in return. There are several types of mycorrhizae, including arbuscular, ectomycorrhizae, and ericoid mycorrhizae, each with different characteristics and roles in the ecosystem.
Mycorrhizal fungi play a crucial role in maintaining ecosystems. They improve soil structure, increase biodiversity, stabilize ecosystems, and help plants adapt to different environmental conditions. Fungi colonize plant roots through spores or hyphae, forming specific structures for nutrient exchange. Plants release carbohydrates that fungi use as an energy source, while fungi absorb mineral nutrients from the soil and transport them to plants. Mycorrhizal fungi increase nutrient absorption, secrete growth hormones and enzymes, and protect plants from heavy metals and salts. The increased nutrient absorption is especially important for phosphorus and nitrogen, which are essential for plant growth.
Mycorrhizal fungi induce numerous physiological changes in plants, resulting in the strengthening of their defense mechanisms. The activation of defense mechanisms includes the production of phytoalexins, strengthening of cell walls, and activation of defense genes, which increases plant resistance to pathogens. This paper explores the wide range of beneficial effects of mycorrhizal fungi, particularly in the context of their role in nutrient absorption, secretion of growth hormones and enzymes, protection from heavy metals and salts, and enhancement of plant resistance to pathogens
Instruments and measures of agrarian policies aimed at reducing greenhouse gases from agriculture
No full textRazličita istraživanja pokazuju kako su uzrok globalnog zagrijavanja emisije stakleničkih plinova. Iz poljoprivrede se u atmosferu ispuštaju metan (CH4), dušikov oksid (N2O) i ugljikov dioksid (CO2). Ciljevi rada su: dati pregled istraživanja o utjecaju poljoprivrede na klimatske promjene, utvrditi emisiju stakleničkih plinova iz poljoprivrede odabranih članica EU i identificirati koje instrumente koristi EU i odabrane članice OECD-a kako bi smanjili emisiju stakleničkih plinova iz poljoprivrede. Rezultati pokazuju kako je emisija stakleničkih plinova najviše zastupljena u stočarstvu i korištenju zemljišta. Države raznim intervencijama žele utjecati na smanjenje stakleničkih plinova i prilagodbu klimatskim promjenama kako bi se do 2050. dostigla nulta stopa emisije. Najveća emisija stakleničkih plinova u EU je u Francuskoj, Italiji, Njemačkoj, Poljskoj i Španjolskoj, a najniže u Estoniji, Hrvatskoj, Latviji, Slovačkoj i Sloveniji. Sve države osim Estonije, Latvije i Poljske u razdoblju 2000.-2021. bilježe smanjenje emisije stakleničkih plinova. Sve promatrane države su do 2050. godine kao cilj smanjenja emisije CO2 za cijelo gospodarstvo odredile neto nula, ali različito postavile ciljeve do 2030. Niti SAD niti Australija nemaju ciljeve vezane uz smanjenje emisije stakleničkih plinova iz poljoprivrede. Takvi ciljevi nisu definirani niti na razini EU, ali pojedine države članice ih imaju. Neki od instrumenata koji se koriste su subvencije za smanjenje emisije CO2 iz poljoprivrede (Australija), krediti i bespovratna sredstva za ulaganja u smanjenje emisije CO2 (SAD) ili potpore (EU, SAD).Various studies show that greenhouse gas emissions are the cause of global warming. Agriculture emits methane (CH4), nitrogen oxide (N2O) and carbon dioxide (CO2) into the atmosphere. The objectives of the paper are: to provide an overview of research on the impact of agriculture on climate change, to identify greenhouse gas emissions from agriculture in selected EU member states and to determine which instruments are used by the EU and selected OECD members to reduce greenhouse gas emissions from agriculture. The results show that greenhouse gas emissions are most pronounced in livestock farming and land use. Through various interventions, countries want to influence the reduction of greenhouse gases and adaptation to climate change in order to achieve a zero emission rate by 2050. Germany, France, Italy, Poland and Spain have the highest greenhouse gas emissions in the EU, while Croatia, Estonia, Latvia, Slovakia and Slovenia have the lowest. All countries except Estonia, Latvia and Poland show a decrease in greenhouse gas emissions in the period 2000-2021. All countries monitored have set net zero as a target for reducing CO2 emissions for the entire economy by 2050, but have set different targets for 2030. Neither the USA nor Australia have targets for reducing greenhouse gas emissions from agriculture. At EU level, such targets are not even defined, but individual member states have them. Some of the instruments used are subsidies to reduce CO2 emissions in agriculture (Australia), loans and grants for investments in CO2 reduction (USA) or incentives (EU, USA)
Knowledge, attitudes and behavior of student-athletes toward sustainable development
No full textCilj ovog rada je istražiti znanje, stavove i ponašanje studenata sportaša prema održivom razvoju te utvrditi postoji li razlika s obzirom na spol, znanstveno područje u kojem studiraju i sport s kojim se bave. Istraživanje je provedeno u ak. god. 2023./24. na uzorku od 167 studenata sportaša (61,7% studentica i 38,3% studenata) koji studiraju u različitim područjima znanosti na Sveučilištu u Zagrebu. Rezultati su pokazali da postoji statistički značajna razlika prema održivom razvoju obzirom na spol, pri čemu studentice sportašice generalno izražavaju veću sklonost prema održivom razvoju u usporedbi sa studentima sportašima. Analiza razlika prema području znanosti je pokazala da studenti sportaši iz tehničkog područja pokazuju nešto niže razine svijesti u odnosu na svoje kolege iz drugih područja znanosti. Istraživanje je također, pokazalo neznatne ali vrijedne razlike među studentima sportašima obzirom na sport kojim se bave. Studenti sportaši uključeni u estetske sportove poput gimnastike i plesa pokazuju nešto veću svijest o održivom razvoju. S druge strane, sportaši u borilačkim sportovima i studenti uključeni u fitness programe pokazuju nešto niže razine svijesti. Zaključno, provedeno istraživanje sugerira potrebu za daljnjim istraživanjima kako bi se bolje razumjelo uzroke razlika u stavovima i ponašanju prema održivosti među studentima sportašima.The aim of this work is to investigate the knowledge, attitudes and behavior of student athletes towards sustainable development and to determine whether there is a difference with regard to gender, the scientific field in which they study and the sport they play. The research was conducted in ac. year 2023./24. on a sample of 167 student athletes (61.7% female students and 38.3% male students) studying in various fields of science at the University of Zagreb. The results showed that there is a statistically significant difference towards sustainable development with regard to gender, with female student athletes generally expressing a greater preference for sustainable development compared to male student
athletes. The analysis of differences according to the field of science showed that student
athletes from the technical field show slightly lower levels of awareness compared to their colleagues from other fields of science. The research also showed slight but valuable differences among student athletes regarding the sport they play. Student athletes involved in aesthetic sports such as gymnastics and dance show a slightly higher awareness of sustainable development. On the other hand, athletes in martial arts and students involved in fitness programs show slightly lower levels of awareness. In conclusion, the conducted research suggests the need for further research to better understand the causes of differences in attitudes and behavior towards sustainability among student athletes
The influence of ageing methods on the physical properties of meat of Buša calves
No full textBuša je jedna od tri izvorne hrvatske pasmine goveda. Smatra se da je meso teladi buše tvrđe od mesa teladi suvremenih pasmina goveda te da se zrenjem mogu poboljšati fizikalna svojsva mesa ove pasmine. Cilj ovog diplomskog rada je bio utvrditi utjecaj različitih načina zrenja na fizikalna svojstva mesa teladi buše. U tu svrhu je zaklano 8 grla muške teladi buše te su prikupljeni uzorci mesa za zrenje koji uključuju dio leđnog mišića m. longissimus dorsi i dio slabinskog dijela m. longissimus lumborum. Nakon 14. i 21. dana zrenja određivana je pH vrijednost, L*, a* i b* parametar boje, otpor presijecanju i gubitak mase tijekom zrenja. Analizirajući utjecaj vrste zrenja na fizikalne pokazatelje kvalitete mesa, utvrđena je statistički značajna razlika (p<0.05) između L* parametra boje ovisno o načinu zrenja te značajno (p<0.01) veći kalo suhog zrenja u odnosu na mokro zrenje. U vrijednostima ostalih fizikalnih pokazatelja kakvoće mesa između načina zrenja nisu utvrđene značajne razlike.Buša is one of the three local Croatian cattle breeds. It is believed that the meat of buša calves is less tender than the meat of calves of modern cattle breeds, and that ageing can improve the physical properties of meat of this breed. The aim of this thesis was to determine the influence of different ageing methods on the physical properties of meat of buša calves. For this purpose, 8 male calves of buša were slaughtered and meat samples were collected for ageing, which include part of m. longissimus dorsi and m. longissimus lumborum. After the 14. and 21. day of aging, the pH value, L*, a* and b* color parameters, shear force and drip loss were determined. Analysing the influence of the type of aging on the physical indicators of meat quality, a statistically significant difference (p<0.05) was found between the L* color parameter depending on the ageing method, and a significantly (p<0.01) higher value of drip loss in dry ageing compared to wet ageing. No significant differences were found in the values of other physical indicators of meat quality between the ageing methods
Yield and phytonutrient content of broccoli microgreens using different spectrum of led lighting
No full textVertikalni uzgoj je tehnika uzgoja bilja u više razina, jedna iznad druge. Uključuje kontrolirane uvjete uzgoja koji optimiziraju rast biljaka kao i primjenu hidroponskih tehnika uzgoja. Cilj rada je utvrditi prinos i sadržaj fitonutrijenata mladih izdanaka brokule iz vertikalnog uzgoja uz primjenu LED dopunskog osvjetljenja različitih valnih duljina. Pokus je postavljen u komori za rast biljaka s kontroliranim uvjetima temperature i vlage zraka (25 ᵒC, 60% relativne vlage zraka). U uzgoju mladih izdanaka brokule, nakon nicanja primijenjeno je dopunsko osvjetljenje svjetlećim, diodama sa tri različita spektra (crveni – 620 nm, plavi – 450 nm i kombinacija crvenog i plavog spektra 50:50%) i trajanjem fotoperioda 14 sati. Berba mladih izdanaka obavljena je 8 dana nakon sjetve. Prinos mladih izdanaka brokule uz primjenu kombiniranog crveno-plavog spektra te plavog spektra LED osvjetljenja iznosio je 1,2 kg/m2, dok je uz primjenu crvenog spektra bio znatno manji i znosio 1,05 kg/m2. Najveći udio suhe tvari mladih izdanaka brokule uz primjenu kombiniranog crveno-plavog spektra LED osvjetljenja iznosio je 6,72 %. Primjena plavog LED osvjetljenja rezultirala je značajno većim sadržajem pigmentnih spojeva (klorofil a, ukupni klorofili, karotenoidi) u mladim izdancima brokule u usporedbi s crvenim, odnosno, kombiniranim crveno-plavim LED osvjetljenjem. Primjena kombiniranog spektra zračenja (620 nm +450 nm) rezultirala je značajno većim sadržajem ukupnih fenola i flavonoida u odnosu na plavi i crveni spektar LED osvjetljenja. Najviši antioksidacijski kapacitet utvrđen je u mladim izdancima uzgojenim uz primjenu kombiniranog crveno-plavog LED osvjetljenja (1228,21 μmol TE/g uzorka).Vertical cultivation is a technique of growing plants in several levels, one above the other. It includes controlled growing conditions that optimize plant growth as well as the application of hydroponic growing techniques. The aim of the work is to determine the yield and content of phytonutrients of young broccoli shoots from vertical cultivation with the use of LED supplemental lighting of different wavelengths. The experiment was set up in a plant growth chamber with controlled temperature and humidity conditions (25 ᵒC, 60% relative humidity). In the cultivation of young broccoli shoots, after emergence, supplemental lighting was applied with fluorescent diodes with three different spectra (red - 620 nm, blue - 450 nm and a combination of red and blue spectrum 50:50%) and a photoperiod duration of 14 hours. Young shoots were harvested 8 days after sowing. The yield of young broccoli shoots with the application of the combined red-blue spectrum and the blue spectrum of LED lighting was 1.2 kg/m2, while with the application of the red spectrum it was significantly lower and amounted to 1.05 kg/m2. The highest proportion of dry matter of young broccoli shoots with the application of the combined red-blue spectrum of LED lighting was 6.72%. The use of blue LED lighting resulted in a significantly higher content of pigment compounds (chlorophyll a, total chlorophylls, carotenoids) in young broccoli shoots compared to red, i.e., combined red-blue LED lighting. The use of a combined radiation spectrum (620 nm +450 nm) resulted in a significantly higher content of total phenols and flavonoids compared to the blue and red spectrum of LED lighting. The highest antioxidant capacity was determined in young shoots grown with the use of combined red-blue LED lighting (1228.21 μmol TE/g sample)
The content of microelements in the French bean's fruit from different cultivations
No full textGrah mahunar (Phaseolus vulgaris L.) je jednogodišnja biljna vrsta iz porodice mahunarki (Fabaceae). Plodovi graha mahunara su mahune koje imaju iznimnu nutritivnu vrijednost i bogate su proteinima, ugljikohidratima, vlaknima, vitaminima i mineralima. Cilj ovog rada bio je utvrditi kako način uzgoja utječe na sadržaj mikroelemenata te hranidbenu vrijednost mahuna na temelju zastupljenosti mikroelemenata u mahunama. Uzorci mahuna prikupljeni su u gradu Zagrebu na tri tržnice, tri trgovačka lanca te tri trgovine ekološkim proizvodima. Nakon sušenja i homogeniziranja uzorci su razgrađeni djelovanjem koncentrirane HNO3 i HClO4 u mikrovalnoj peći, a koncentracije željeza, cinka, mangana i bakra određene su atomskim apsorpcijskim spektrometrom. Vrijednost suhe tvari u mahunama kretala se između 6,74 i 12,54 %. Udio mikroelemenata u suhoj tvari mahuna (mg/kg ST) iznosio je Fe 49,86-188,9, Zn 23,43-43,47, Mn 2,53-42,3, Cu 6,57-9,74, a u svježoj tvari (mg/100 g svježe tvari) Fe 0,49-1,96, Zn 0,19-0,42, Mn 0,03-0,32 i Cu 0,05-0,11. Najveće prosječne količine željeza, cinka i mangana u suhoj i svježoj tvari mahuna utvrđene su u trgovinama ekološkim proizvodima, dok je najveća prosječna vrijednost bakra u suhoj tvari utvrđena u mahunama uzorkovanim u trgovačkim lancima, a najveća prosječna koncentracija bakra u svježoj tvari u uzorcima sa tržnica i iz trgovina ekološkim proizvodima. Prema Uredbi o informiranju potrošača o hrani može se zaključiti da se konzumacijom 100 g ispitivanog graha mahunara podmiruje 4,21- 8,0 % dnevnih potreba čovjeka za željezom, 2,5- 3,8 % dnevnih potreba za cinkom, 4,0-13,0 % dnevnih potreba za manganom i 7,0-8,0 % dnevnih potreba za bakrom.French bean (Phaseolus vulgaris L.) is an annual plant species from the legume family (Fabaceae). French bean's fruit are pods that have exceptional nutritional value and are rich in proteins, carbohydrates, fibers, vitamins and minerals. The aim of this work was to determine how the method of cultivation affects the content of microelements and the nutritional value of the pods based on the presence of microelements in the pods. Pods samples were collected in the city of Zagreb at three markets, three retail chains and three shops with organic products. After drying and homogenization, the samples were decomposed by the action of concentrated HNO3 and HClO4 in a microwave oven, and the concentrations of iron, zinc, manganese and copper were determined with an atomic absorption spectrometer. The value of dry matter in pods ranged between 6,74 and 12,54 %. The proportion of microelements in the dry matter of pods (mg/kg ST) was Fe 49,86-188,9, Zn 23,43-43,47, Mn 2,53-42,3, Cu 6,57-9,74, and in fresh matter (mg/100 g of fresh matter) Fe 0,49-1,96, Zn 0,19-0,42, Mn 0,03-0,32 and Cu 0,05-0,11. According to the Regulation on the provision of food information to consumers, it can be concluded that the consumption of 100 g of the studied french beans satisfies 4,21-8,0 % of the daily human needs for iron, 2,5-3,8 % of the daily needs for zinc, 4,0-13,0 % of the daily needs for manganese and 7,0 -8,0 % of daily copper needs
Quality and usage potential of sheep manure in the Bjelovar-Bilogora county
No full textOvčji stajski gnoj važan je nusproizvod ovčarske proizvodnje. U Bjelovarsko-bilogorskoj županiji (BBŽ) se uzgaja više od 10% ukupnog broja ovaca registriranih u RH. Cilj ovog rada bio je utvrditi kvalitetu ovčjeg stajskog gnoja na području BBŽ i mogućnosti njegovog korištenja. Kvaliteta gnoja je utvrđena na temelju rezultata laboratorijskih analiza uzoraka prikupljenih tijekom 2022. i 2023. godine s ovčarskih farmi na području BBŽ. U uzorcima utvrđene su prosječne vrijednosti suhe tvari, vlage, pH, organskog ugljika, dušika, fosfora i kalija. Rezultati istraživanja upućuju na značajne varijacije u kvaliteti gnoja ovisno o godini i sezoni prikupljanja uzoraka. Utvrđen je statistički značajan utjecaj godine na sadržaj suhe tvari i organskog ugljika. Prosječne vrijednosti sadržaja suhe tvari značajno su se razlikovale između sezona uzorkovanja. PH vrijednost je imala relativno stabilne vrijednosti između sezona uzorkovanja. Najvarijabilniji sastojci bili su fosfor i kalij, a najmanje dušik i organski ugljik. Varijabilnosti upućuju na neujednačenu kvalitetu ispitivanih uzoraka. Analizirani uzorci zbog značajnog sadržaja suhe tvari i stabilne pH vrijednosti upućuju na visoki potencijal ovčjeg stajskog gnoja kao organskog gnojiva za primjenu na različitim vrstama tla. Ovčji stajski gnoj osim kao organsko gnojivo može se koristiti u proizvodnji bioplina.Sheep manure is an important byproduct of sheep farming. In the Bjelovar-Bilogora County (BBŽ), more than 10% of the total number of sheep registered in Croatia are raised. The aim of this paper was to determine the quality of sheep manure in the BBŽ area and the possibilities for its use. The quality of the manure was determined based on the results of laboratory analyses of samples collected during 2022 and 2023 from sheep farms in the BBŽ area. The samples revealed average values of dry matter, moisture, pH, organic carbon, nitrogen, phosphorus, and potassium. The research results indicate significant variations in the quality of manure depending on the year and season of sample collection. A statistically significant effect of the year on the dry matter and organic carbon content was found. The average dry matter content varied significantly between sampling seasons. The pH values remained relatively stable between sampling seasons. The most variable components were phosphorus and potassium, while nitrogen and organic carbon were the least variable. The variability suggests an inconsistent quality of the samples tested. The analyzed samples, due to their significant dry matter content and stable pH values, indicate a high potential for sheep manure as an organic fertilizer for application on various soil types. In addition to its use as organic fertilizer, sheep manure can also be used in biogas production
Influence of edible chitosan coating on strawberry fruit quality
No full textJestivi omotači predstavljaju ekološki prihvatljivi materijal za očuvanje kvalitete i produljenja roka trajanja svježeg voća. Jagoda je popularno voće i važan dio suvremene prehrane koje brzo propada nakon berbe. U ovom radu ispitan je utjecaj jestivog omotača kitozana na sadržaj bioaktivnih tvari (polifenola, antioksidacijska aktivnost, antocijani), ukupnih proteina i brojnost odabranih grupa mikroorganizama (aerobni mezofili, aerobnih psihrotrofi, enterobakterije, kvasaca i plijesni) na plodu jagode. Provedbom testa analize varijance (ANOVA) na razini značajnosti od 5 % utvrđeno je da postoji razlika među skupinama. Provedbom post-hoc t-testova uz Bonferronijevu korekciju (p<0,05) na razini značajnosti utvrđeno je da se ukupni sadržaj polifenola i antocijanina te antioksidacijska aktivnost nakon 4. dana statistički značajno razlikuju između kontrolne skupine i skupine s jestivim omotačem kitozanom s dodatkom jabučne komine. Oba jestiva omotača značajno inhibiraju rast aerobnih mezofilnih bakterija, plijesni i kvasaca, dok psihrotrofne bakterije i enterobakterije nisu uopće detektirane. Stoga, kitozan se pokazao kao bolji omotač za produženje roka trajanja jagoda.Edible coatings represent an environmentally friendly material for preserving the quality and extending the shelf life of fresh fruit. The strawberry is a popular fruit and an important part of the modern diet, which quickly deteriorates after harvesting. In this paper, the influence of the edible chitosan coating on the content of bioactive substances (polyphenols, antioxidant activity, anthocyanins), total proteins and the number of selected groups of microorganisms (aerobic mesophiles, aerobic psychrotrophs, enterobacteria, yeasts and molds) on strawberry fruit was examined. By performing an analysis of variance (ANOVA) test at a significance level of 5 %, it was determined that there was a difference between the groups. By performing post-hoc t-tests with Bonferroni's correction (p<0.05) at the level of significance, it was determined that the total content of polyphenols and anthocyanins and the antioxidant activity after the 4th day were statistically significantly different between the control group and the group with the edible chitosan coating with the addition apple pomace. Both edible casings significantly inhibit the growth of aerobic mesophilic bacteria, molds and yeasts, while psychrotrophic bacteria and enterobacteria were not detected at all. Therefore, chitosan proved to be a better coating for extending the shelf life of strawberry
Growth of pure culture of microalgae under different conditions of salinity and daylength
No full textMikroalge zbog brze reprodukcije i visokog sadržaja ulja ističu se kao sirovina budućnosti u
proizvodnji biogoriva. Donedavno su predstavljale ključne čimbenike u mrjestilištima riba i
školjkaša, ali u posljednjih dvadeset godine sve su značajnija sirovina u prehrambenoj i
farmaceutskoj industriji te industriji biogoriva. Na rast mikroalgi utječu brojni čimbenici
kvalitete uzgojne sredine. Razumijevanje tih čimbenika od ključne je važnosti za optimizaciju
njihovog uzgoja i održivu proizvodnju. U ovom je radu istraživan utjecaj saliniteta i dužine
svjetlosnog dana na brzinu rasta čiste kulture mikroalge Isochrysis galbana. Pokus je proveden
u dva ponavljanja te u dvije faze. U prvoj fazi je ispitan utjecaj različiti saliniteta (15, 25 i 35
ppt) dok su ostali uvjeti uzgoja bili konstantni. U drugoj je fazi ispitan utjecaj različitih duljina
svjetlosnog dana (16, 18 i 24 sata). Rezultati su za obje faze uspoređeni ANOVA testom.
Najbolji rast postignut je pri salinitetu od 25 ppt te pri konstantnom osvjetljenju, odnosno
duljini svjetlosnog dana od 24 sata.Microalgae, due to their rapid reproduction and high oil content, stand out as a future raw
material in the production of biofuels. Until recently, they played a key role in fish and shellfish
hatcheries, but in the last two decades, they have become increasingly important as a raw
material in the food, pharmaceutical, and biofuel industries. The growth of microalgae is
influenced by various factors in the cultivation environment. Understanding these factors is
of crucial importance for optimizing their cultivation and ensuring sustainable production. This
study investigates the impact of salinity and photoperiod on the growth rate of a pure culture
of the microalgae Isochrysis galbana. The experiment was conducted in duplication and in two
phases. The first phase examined the influence of different salinities (15, 25, and 35 ppt) while
keeping other cultivation conditions constant. In the second phase, the impact of different
photoperiods (16, 18, and 24 hours) was investigated. The results for both phases were
compared using ANOVA testing. The best growth was achieved at a salinity of 25 ppt and under
constant illumination, corresponding to a photoperiod of 24 hours
Prediction of subclinical ketosis risk in dairy cows based on metabolic indicators and milk composition
No full textKetoza je metabolički poremećaj koji se javlja u periodu neposredno poslije telenja, a najčešće zahvaća visoko proizvodne krave. U radu je opisana ketogeneza i ketoliza, odnosno sinteza i trošenje ketonskih tijela (acetoacetata, β-3-hidroksibutirata i acetona), kao i kontrola ketogeneze na koju utječu hormoni inzulin i glukagon. S obzirom na prisutnost kliničkih znakova ketoza se pojavljuje u subkliničkom ili kliničkom obliku. Nadalje, s obzirom na etiopatogenezu, ketoza se još dijeli na tip I i tip II koji imaju zajednički uzrok, negativnu energetsku ravnotežu, ali imaju drugačiji put nastanka. Ketoza se može dijagnosticirati brzim testovima, koji određuju koncentraciju ketonskih tijela u krvi, mlijeku i urinu ili pak laboratorijskim metodama. Prevencija ketoze se temelji na postizanju optimalne kondicije u suhostaju ali i davanju prekursora glukoze u obroku kravama u ranoj laktaciji.
Prolazno povećanje sadržaja mliječne masti u mlijeku kao i promjena omjera sadržaja masti i proteina u mlijeku, te prisutnost povećane razine 3BH u krvi rani su pokazatelji promjena u energetskom metabolizmu krave, dok prisutnost ketonskih tijela u tjelesnim izlučevinama (mlijeko, urin) ukazuju na već uznapredovali stadij navedenih metaboličkih poremećaja.Ketosis is a metabolic disorder that occurs in the period immediately after calving and most often affects highly productive dairy cows. The paper describes ketogenesis and ketolysis, the synthesis and utilization of ketone bodies (acetoacetate, β-3-hydroxybutyrate, and acetone), as well as the control of ketogenesis influenced by the hormones insulin and glucagon. According to clinical signs, ketosis manifests as subclinical or clinical ketosis, and it is further divided into Type I and Type II, which share a common cause, negative energy balance, but have different pathophysiological pathways. Ketosis can be diagnosed through rapid tests that determine the concentration of ketone bodies in blood, milk, and urine, and it can also be diagnosed using laboratory methods.
The prevention of ketosis is based on achieving optimal condition in dryness, but also on giving glucose precursors in the diet to cows in early lactation. A transient increase in the milk fat content as well as a change in the ratio of fat and protein content in milk and the presence of an increased level of 3BH in the blood are early indicators of changes in the cow's energy metabolism, while the presence of ketone bodies in body secrets (milk, urine) indicate an already advanced stage of the mentioned metabolic disorders