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Herbert Evans and Katherine Bishop discovered vitamin E in 1922. Vitamin E is one of the main antioxidants, slows down the development of Alzheimer's disease, protects the skin from unfavorable UV rays. Its positive effect on the human body ensured its significant place in nutrition. Humans cannot synthesize vitamin E, therefore it must be ingested through food. Foods rich in vegetable oils and green vegetables are considered a good source of vitamin E, while food of animal origin contains less vitamin E. Determination of vitamin E concentration in feed for laying hens is important because eggs are one of the sources of vitamin E in the human diet, and the concentration of vitamin E in egg yolk depends on the composition of the feed consumed by laying hens. A method developed by Pinheiro-Sant et al. was used for extraction of vitamin E from feed for laying hens. The influence of sample particle size, sample:extraction mixture ratio and optimizing the composition of the extraction mixture was investigated. All measurements were performed on a sample of laying hens feed available on the market, and the concentration of vitamin E was determined using HPLC. The determined concentration of vitamin E in the grinded and sieved samples was 266, 613 mg/kg, while in the non-grinded samples it was 199, 293 mg/kg, which is a difference of 33.78%. Sample:extraction mixture ratios (1:5, 1:10, 1:25 and 1:50) were investigated. The best determined ratio is 1:25 where the measured concentration of vitamin E was 329, 319 mg/kg. By replacing hexane:ethyl acetate (85:15, v/v) with hexane:ethyl acetate (65:35, v/v) better results were obtained. The measured concentration of vitamin E was 11.17% higher.

U radu se istražuje kvaliteta prsnog mesa Ross 308 brojlera u dobi od 42 dana. U istraživanju je analizirano 30 uzoraka. Nakon klasifikacije prema boji mišića utvrđeno je 20 uzoraka blijedog, mekanog i vodnjikavog (BMV) i 10 normalnog. Tamnog, čvrstog i suhog mesa (TČS) nije bilo. Za vrednovanje kvalitete mesa korišteni su sljedeći pokazatelji: boja (CIE L*, a* b*), pH vrijednost, gubitak mesnog soka (%) i profil masnih kiselina. Pri klasifikaciji prsnog mesa prema boji upotrijebljeni su sljedeći pokazatelji: CIE L* od 44 do 53 meso normalnih svojstava, CIE L*> 53 BMV i CIE L*< 44 TČS meso. Vrijednosti boje mesa bile su statistički značajno veće kod BMV mesa u odnosu na meso normalnih svojstava (CIE L* 57, 01 : 50, 08 ; P

Consumer demand for high quality and safe foods that will have a positive impact on their health has increased in recent years. Today, it is possible to meet those demands by combining the genetic potential of domestic animals and applying different feeding strategies. Nutrigenomics is one of the “omics” sciences that studies the iteraction between nutrients and the genome together with their influence on metabolic and physiological processes in the body. While nutrition of domestic animals is solely based on studying the influence of nutrients on animal health and production traits, nutrigenomics integrates the fields of nutrition, genomics, molecular genetics and bioinformatics. By understanding the molecular relationships between different forms and/or concentrations of nutrients in feed and genes, it is possible to answer the question of how small changes in the diet of farm animals can produce a quality product with positive effects on human health. The aim of this article is to describe how the manipulation of adding different nutrients in the feed affects the expression of different genes in chicken and consequently alters their phenotype.

U radu se prikazuju rezultati istraživanja utjecaja genotipova Ross 308 i Cobb 500 brojlera muškog spola na klaonička svojstva i tehnološke pokazatelje prsnog mišićnog tkiva. Na svježim i zamrznutim uzorcima istraživani su sadržaji masnih kiselina kao i TBAR S vrijednosti u mišićnom tkivu. Meso prsa i zabataka čuvano je u zamrzivaču 30 dana na -20 °C. Tov brojlera organiziran je na konvencionalni način (jednaki uvjeti za oba genotipa). Masa trupova, nakon 35 dana tova, iznosila je za Ross 308 brojlere 1576,85 g a Cobb 500 brojlere 1586,40 g (P>0,05). Utvrđene su značajne razlike u CIE L* i CIE b* pokazateljima boje, kalu kuhanja (%) i WBSF (N) vrijednostima između genotipova (P0,05)., The paper presents the results of research on the influence of Ross 308 and Cobb 500 genotypes of male broilers on slaughtering properties and technological indicators of breast muscle tissue. of Fatty acids contents and TBAR S values of muscle tissue were determined on fresh and frozen samples. Breast and thigh meat samples were stored in freezer at -20°C for 30 days. Broilers were fattened in a conventional manner (same conditions for both genotypes). After 35 days of fattening, Ross 308 broiler carcass weighed 1576.85 g, and Cobb 500 broiler carcass weighed 1586.40 g (P>0.05). Significant differences were found for CIE L* and CIE b* color indicators, cooking loss (%) and WBSF (N) values between genotypes (P0.05).

In this paper, authors summarise studies refferering to enrichment of breast and thigh muscles with carnosine that has an important function in physiological processes. Research has shown that carnosine improves quality of chicken meat. By adding amino acids β-alanine and L-histidine in chickens’ feed, carnosine synthesizes in skeletal muscles, brain, heart muscle and olfactory receptor cells. It has been determined that the content of carnosine depends on the type of muscle (white or dark meat), broiler genotype as well as sex. Chicken meat is sensitive to oxidation processes, but lipid oxidation can be efficiently prevented by enriching meat with carnosine., U radu se istražuje obogaćivanje mišića prsa i zabataka karnozinom, koji ima važnu funkciju u fiziološkim procesima. Istraživanja su pokazala da karnozin poboljšava kvalitetu pilećega mesa. Dodavanjem aminokiselina β-alanina i L-histidina u hranu pilića sintetizira se karnozin u skeletnim mišićima, mozgu, srčanome mišiću i stanicama čula mirisa. Ustanovljeno je da sadržaj karnozina ovisi o tipu mišića (bijelo ili tamno meso) te genotipu brojlera, kao i o spolu. Meso pilića osjetljivo je na oksidacijske procese, ali se lipidna oksidacija može efikasno prevenirati obogaćivanjem mesa karnozinom.

Carnosine (β-alanyl-L-histidine) and anserine (β- alanyl-1-methyl-L-histidine) are dipeptides that play a significant role in physiological functions in the human body. They are present in the skeletal muscles and brain tissue of many vertebrates, and from the literature it can be seen that white chicken meat has high concentrations of these peptides. By designing a feed mixture with an increased content of the amino acids L-histidine and β-alanine, their concentration in the meat can be increased. The aim of this study was to examine the influence of genotype and muscle tissue on meat colour and content of carnosine and anserine. The research was conducted on Cobb 500 and Ross 308 broilers during 42 fattening period during which broilers were fed with commercial fodder mixtures. After slaughtering and processing the carcass, the colour of the breast and shoulder meat was measured (CIE L*, CIE a*, CIE b*). Obtained results showed that muscle tissue has a statistically significant influence on meat colour (P˂0.05), while genotype has influenced only on CIE b* value (˂0.001). The content of carnosine and anserine in the meat samples of breast and shoulder indicate that genotype has no influence on the content of the mentioned dipeptides in the meat (P>0.05), while the muscle tissue has a significant influence (P˂0.001) on their deposition. A significantly higher content of carnosine and anserine was found in breast meat compared to shoulder meat in both genotypes.

Potrošači danas zahtijevaju hranu koja neće samo zadovoljavati njihove nutritivne potrebe, već imati i pozitivan učinak na njihovo zdravlje. Stoga su danas napori stočarske proizvodnje usmjereni na uzgoj životinja na način da njihovi proizvodi budu dovoljno kvalitetni, higijenski ispravni, ali i da doprinose očuvanju zdravlja potrošača. Optimizacija i manipulacija hranidbe domaćih životinja utječe na njihova proizvodna svojstva, poput rasta, kvalitete finalnog proizvoda i zdravlja životinja, no uporabom različitih hranidbenih strategija može se dobiti i proizvod koji će u odnosu na konvencionalan imati i određeni pozitivan učinak na ljudsko zdravlje. Uporabu takvih strategija, kao i njihov kratkoročni i dugoročni učinak na organizam životinje potrebno je detaljno proučiti, a alate koji nam to omogućuju daje upravo nutrigenomika. Nutrigenomika je relativno nova grana u nizu „omics“ znanosti kojom je moguće utvrditi kako promjene u hranidbi životinje mogu utjecati na aktivnost pojedinih gena u njenu organizmu. Informacije prikupljene ovim putem omogućavaju bolje razumijevanje hrane i hranidbe dajući detaljni uvid u načine djelovanja biološki aktivnih tvari te utjecaj njihovih pojedinih koncentracija i oblika na organizam, omogućavajući na taj način njihovu optimizaciju u cilju dobivanja kvalitetnog proizvoda s pozitivnim utjecajem na ljudsko zdravlje.

Cilj rada bio je vrednovanje utjecaja različitih hranidbenih tretmana u tovu brojlera na efikasnost primijenjene hranidbe. U istraživanju su upotrjebljeni Ross 308 pilići (N=120) koji su bili podijeljeni u 4 skupine. Hranidbeni tretmani razlikovali su se u finišer smjesama koje su osim ostalih krmiva sadržavale i 5% ulja i to: T1 suncokretovo, T2 sojino, T3 repičino i T4 laneno ulje. Smjese su bile izbalansirane na razini 20 % sirovih proteina i 13, 5 MJ Kg/Me. Sve skupine pilića nalazile su se u istom peradnjaku a hranjene i napajanje bilo je ad libitum. U radu su istraženi proizvodno ekonomski pokazatelji: Indeks proizvodne efikasnosti (PEI), Europski brojlerski indeks (EBI), Indeks ekonomske efikasnosti (EEI) i indeks troškova hrane (CIF). Efikasnost proizvodnih indeksa bila je sljedeća (PEI i EBI): T1 363 i 351, T2 347 i 335, T3 362 i 351 i T4 367 i 359. PEI pokazatelji ovisili su u većoj mjeri o završnoj masi brojlera i konverziji hrane. Vrijednosti EBI slijedile su vrijednosti PEI pokazatelja. Za komparaciju produktivnosti performansi više tretmana (skupina) brojlera prikladni su PEI i EBI pokazatelji. Ekonomska efikasnost i troškovi hrane mogu se prikazati pomoću vrijednosti EEI i CIF pokazatelja.

Ekstrakcija masti i određivanje profila masnih kiselina jedna je od važnijih analiza prema kojima se određuje kvaliteta hrane za nesilice i jaja. Standardna metoda ekstrakcije masti iz hrane za nesilice je Soxhlet ekstrakcija koja je dugotrajna, zamorna i nastaje relativno velika količina organskog otpada što ima za posljedicu povećanje troškova ekstrakcije i analize. Zbog svega navedenog potreba za unaprjeđenjem postupka ekstrakcije odnosno smanjenje količine organskog otpada i skraćivanje vremena trajanja ekstrakcije je od iznimne važnosti. Na 6 uzoraka hrane za nesilice primijenjene su standardna metoda ekstrakcije Soxhlet ekstrakcija (SE) i ekstrakcije potpomognute ultrazvukom – direktna ultrazvučna ekstrakcija (DUE) i indirektna ultrazvučna ekstrakcija (IUE), a dobiveni rezultati su uspoređeni. Najkraće vrijeme ekstrakcije je DUE 10 min., IUE 120 min. dok je SE 480 min. Udio masti u uzorcima hrane za nesilice kretao se u rasponu 5, 2-6, 4 % za IUE, 3, 97-4, 3 % za DUE a za SE 3, 72- 7, 9 %. Profil masnih kiselina pomoću plinske kromatografije određen je nakon što su ekstrahirani triacilgliceroli prevedeni u metilne estere masnih kiselina uz BF3 u metanolu kao katalizatorom. Najviše masnih kiselina određeno je u uzorcima koji su ekstrahirani DUE i IUE – ukupno 22, u uzorcima ekstrahiranima SE određeno je 15. Od značajnih masnih kiselina (SFA, MUFA, PUFA n-3, PUFA n-6) najviše ih je određeno nakon DUE i IUE (9), dok ih je nakon SE određeno 5.

Cilj rada bio je istražiti obogaćivanje pilećeg mesa anserinom pri uporabi smjesa s dodatcima ß- alanina, L-histidina i magnezijevog oksida (MgO). Istraživanje je provedeno na 120 Cobb 500 tovnih pilića koji su bili podjeljeni u 4 pokusne skupine. Do 21. dana pilići su hranjeni starter smjesom komercijalnog sastava, a od 22.-42. dana finišer smjesama i to: P1=kontrolna skupina bez dodatka amino kiselina i MgO ; P2=0, 5% ß- alanina+0, 24% MgO ; P3=0, 25% L-histidina+0, 24% MgO i P4=0, 20% ß-alanina+ 0, 10% L-histidina+0, 24% MgO. Obradom podataka utvrđeno je da hranidbeni tretmani kao i interakcija tretmana i vrste tkiva nisu utjecali na deponiranje anserina (P>0, 05) u mišićno tkivo. Međutim, ustanovljena je statistički visoko značajna razlika u koncentracijama anserina između mišića prsa i zabataka (P

The role of lutein in human and animal health has already been investigated. Due to its importance, it is of great interest to determine its content in the food we consume or is consumed by animals whose products we use in our diet. In this study, the influence of particle size and dry matter (sample):extraction mixture ration on determination of lutein content in laying hens feed was investigated. Mixture of methanol and acetone, 0.2% BHT solution and 40% KOH solution was used as extraction mixture. All extractions were performed on the same samples and assisted by an ultrasonic probe. The lutein content of the samples was determined by means of HPLC with a UV- VIS detector at 450 nm. In ground samples, the determined content of lutein in mg / kg of sample is 52% better compared to ungrinded samples. Comparing the results obtained by the same method but with saponification, 3% more lutein was determined with saponification and the RSD value was significantly reduced (from 1.498% to 0.420%). The ratios of dry matter:extraction mixture: 1: 5, 1:10, 1:20 and 1:40 were investigated, and the obtained results (3, 152 ; 3, 956 ; 5, 148 and 2, 015 mg / kg of sample) indicate that the best ratio is 1:20.

Cilj istraživanja bio je odrediti utjecaj težinskih razreda jaja na pokazatelje kvalitete. Istraživanje kvalitete jaja obavljeno je na ukupno 120 jaja, podrijetlom od kokoši Tetra SL držanih u obogaćenim kavezima i hranjenih komercijalnom krmnom smjesom za nesilice izbalansiranom na 17, 6 % proteina i 11, 84 MJ ME/kg hrane. Prikupljena jaja podijeljena su u 4 razreda prema masi S (˂53 g), M (53-63 g) L(63-73 g) i XL (˃73 g). Pokazatelji kvalitete jaja utvrđeni su uređajem Nobel Digital Egg Tester 6500, dok je pH vrijednost žumanjaka i bjelanjaka utvrđena pH metrom. Visina i dužina jaja određena je pomičnom mjerkom, masa osnovnih dijelova vagom, a vrijednosti su korištene za izračun indeksa oblika i udjela osnovnih dijelova u jajetu. U istraživanju je utvrđeno da razred jaja ima utjecaj na indeks oblika, masu jaja, visinu, širinu i indeks žumanjka, debljinu ljuske, pH bjelanjka i žumanjka, te udjele osnovnih dijelova (P˂0, 05), a nema utjecaja na visinu bjelanjka, HJ, boju žumanjka i čvrstoću ljuske (P˃0, 05).

Carnosine is a natural metabolite in chicken cells with antioxidant activity. It derives from the amino acids β-alanine and L-histidine with carnosine synthase enzyme action. Larger quantities of this metabolite are present in skeletal and brain tissue. Anserine is formed by carnosine methylation. Recent researches have shown that carnosine can prolong cell lifetime, rejuvenate old cells, inhibit protein glycosylation and preserve cellular homeostasis. It is important in neurotransmission maintainance. Carnosine inhibits lipid oxidation and improves stability during meat storage. There is a difference in the carnosine content in some parts of chickens' carcass. Breast muscles (white meat) contain more carnosine than muscles of drumsticks and thighs (dark meat). Genetic basis of broilers and sex also affect carnosine and anserine content in muscles. Higher carnosine values were determined in the thighs meat of female chickens (339.28 µg/g tissue) compared to male chickens (319.29 µg/g tissue, P˃0.05). White meat of female chickens contains 1200.05, and of male ones 684.82 µg/g tissue in standard breeding. Carnosine concentrations in both animal and human muscle tissue can be increased by daily ration supplemented with amino acids (β-alanine and L- histidine). Carnosine deposition in the breast and thigh muscles depends on the added concentrations of some amino acids in the broilers feed.

The self-sufficiency and production of table eggs, as well as the balance of imports and exports in the period from 2013 to 2019 are investigated in this paper. In the aforementioned period, egg production increased by 8.3%, which was insufficient for domestic needs, and the market deficit was compensated by permanent imports. Self-sufficiency decreased to 95 and 90%, respectively. The importance of eggs in human diet, as well as their consumption, is also shown. Official statistical data were used to analyse the situation. Linear and exponential functions were used to describe the phenomena. Research has shown the specifics of egg production and consumption in the Republic of Croatia. Annual egg imports ranged from 2.6 to 15.4%. In order for the Republic of Croatia to be more competitive on the European market, it is necessary to intensify egg production and produce eggs more economically. It is assumed that in the coming period there will be an increase in egg production and consumption in the Republic of Croatia and in EU countries.

Considering their nutritional composition eggs represent an excellent source of nutricines. Because of their availability on the market and good price, they are often consumed both in the world and in our country. In this research, eggs of weight class L (63-73 g weight) produced at the farms of two domestic producers (A, B) were used. Eggs of both producers are available at shopping centres where they are stored at 4˚C. For nutricine analysis total of 20 eggs (10 from each producer) were used. The nutricines: lutein, vitamin E, selenium and omega-3 fatty acids were analyzed in eggs. Significant higher (P˂0.001) lutein content was found out in egg yolks of producer A (1.06 mg/100 g) compared to producer B (0.682 mg/100 g). There was no difference in content of vitamin A and selenium in egg yolks between producer A and B (8.57: 8.09 mg/100 g, P=0.129 ; 0.501 and 0.485 μg/g, P=0.635, respectively). The total content of SFA, MUFA, n-6 and n-3 PUFA and the n-6 PUFA/n-3 PUFA ratio in 100 g of the edible part of the egg was a little higher in eggs of producer A compared to producer B (P˃0.05). It is confirmed that the feeding of laying hens with feed mixtures that have increased content of nutricines may have an impact on a higher amount of nutricines in eggs. Such eggs may have a significant role in human nutrition aiming to fulfil the daily requirement of nutricines.

U radu se istražuju mišljenja konzumenata o značajkama omega-3 jaja koja se nalaze na hrvatskom tržištu. Anketno istraživanje provedeno je u Osječko-baranjskoj županiji. Ukupno su uključena 272 ispitanika oba spola u dobi od 18-65 godina. Anketni listovi popunjeni su pomoću intervjua. Uvodno pitanje glasilo je: Da li ste upoznati s omega-3 jajima - obogaćenim proizvodom? Od ukupnog broja pozitivno su odgovorile 144 osobe (52, 9%) i to 76 muških (M) i 68 ženskih (Ž) ispitanika, a 128 osoba (47, 1%) nije bilo upoznato s funkcionalnim proizvodima, posebice omega-3 jajima. Za vrednovanje odgovora upotrijebljena je Likertova skala od 1 (min) do 7 (max) ocjena. Oba spola ispitanika smatraju omega-3 jaja sigurnim proizvodom (4, 74 M: 4, 76 Ž) i vjeruju podacima na deklaraciji (4, 12 M : 4, 17 Ž). Ženske osobe više vjeruju od muških osoba (4, 35 Ž : 4, 28 M) u deklarirane karakteristike omega-3 jaja koje se odnose na prirodno povećani sadržaj omega-3 masnih kiselina za više od 30% u odnosu na konvencionalna jaja (EPA + DHA 80 mg) te doprinose normalnoj funkciji srca. U znanstvenu provjeru deklariranih karakteristika jaja i njihove konzumacije od strane zdravih osoba, više povjerenja imaju muški (3, 05 i 3, 68) od ženskih ispitanika (2, 85 i 3, 47). Oba spola voljna su koristiti omega-3 jaja u svojoj prehrani (4, 66 M i 4, 69 Ž) ukoliko im mogućnosti to dozvoljavaju.

Presentation of original research article Anti- Inflammatory Potential of n-3 Polyunsaturated Fatty Acids Enriched Hen Eggs Consumption in Improving Microvascular Endothelial Function of Healthy Individuals—Clinical Trial by Ana Stupin, Martina Mihalj, Nikolina Kolobarić, Petar Šušnjara, Luka Kolar, Zrinka Mihaljević, Anita Matić, Marko Stupin, Ivana Jukić, Zlata Kralik, Manuela Grčević, Gordana Kralik, Vatroslav Šerić and Ines Drenjančević. Funding: #KK.01.1.1.01.0010 European Structural and Investment Funds grant for the Croatian National Scientific Center of Excellence for Personalized Health Care, University of Josip Juraj Strossmayer Osijek

U istraživanju utjecaja dodatka ekstrakta cvijeta nevena (Tagetes erecta L.) u hrani kokoši na boju žumanjaka svježih i kuhanih jaja te sadržaj luteina, korištene su 72 nesilice hibrida Tetra SL. Nesilice su podijeljene u dvije pokusne skupine K = kontrolna bez dodatka ekstrakta cvijeta nevena (eng. Marigold Flower Extract, MFE) i L = u smjesi dodano 100 mg MFE/kg. Nesilice su držane u obogaćenim kavezima u istim tehnološkim uvjetima uz ukupno 16 sati dnevnog svjetla. Krmna smjesa bila je izbalansirana na 18% sirovih proteina i 11, 40 MJ ME/kg hrane, a nesilice su konzumirale hranu i vodu ad libitum. Nakon 5 tjedana hranidbe nesilica uzorkovana su jaja L težinskog razreda za analizu sadržaja luteina u žumanjku, te analizu boje žumanjaka svježih i kuhanih jaja. Statistički značajno veći sadržaj luteina utvrđen je u jajima L skupine u odnosu na skupinu K (P˂0, 05). Korišteni hranidbeni tretman L imao je statistički značajno intenzivniju boju svježih i kuhanih žumanjaka (P˂0, 05) u usporedbi s jajima skupine K. Iz rezultata se može zaključiti da je opravdano koristiti MFE dodatak u hrani nesilica kako bi se u jajima povećao sadržaj luteina, ali i utjecalo na intenzivniju boju žumanjaka.