Legla visokoplodnih krmača često karakterizira varijabilnost porodnih masa prasadi i češća pojava lagane prasadi manje vitalnosti, što može negativno utjecati na proizvodne pokazatelje prasadi u ...kasnijim fazama uzgoja. Stoga je cilj rada bio utvrditi utjecaj porodnih masa prasadi na farmi visokoplodnih krmača na dnevne priraste prasadi u laktaciji i uzgoju. U istraživanje je bilo uključeno 296 prasadi iz prasenja 25 krmača hibridne linije Pen Ar Lan u razdoblju između prosinca 2014. i siječnja 2015. Analiziran je prosječni dnevni prirast prasadi od rođenja do kraja razdoblja uzgoja u dobi od 83 dana. Porodna masa značajno je utjecala na dnevne priraste prasadi tijekom laktacije i uzgoja. Prasad koja je pripadala razredima manjih porodnih masa imala je značajno manje dnevne priraste u odnosu na prasad koja je pripadala razredima s većim porodnim masama. Dobiveni rezultati upućuju na potrebu poduzimanja mjera s ciljem smanjenja broja avitalne prasadi manjih porodnih masa prasadi kako bi se omogućilo bolje preživljavanje i zadovoljavajući rast prasadi iz legala visokoplodnih krmača.
In this study, the effects of first thinnings having different intensities in oriental beech (
Fagus orientalis
Lipsky) plantation areas were investigated in terms of diameter and height growth of ...trees. Sample plots were chosen from oriental beech plantation areas which are within the boundaries of Maçka–Yeşiltepe and Vakfıkebir districts of Trabzon province, Turkey. With removing of 0%, 10%, 25% and 40% of basal area in a hectare of stands which are in sapling stage, sample plots were established by applying thinnings which are in four different intensities (control, light, moderate, strong). After the thinning applications, basal areas were calculated by measuring diameters and heights of trees in established sample plots in order to reveal stand growth. The effects of thinnings were revealed related to some stand characteristics (average diameter, basal area, average height, relative diameter increment, etc.) and determined chosen trees. The effect of thinning intensity on average diameter, basal area, and volume values is statistically important in every two plantations. 2-year results showed that thinning increased the diameter increment significantly, and the increase in diameter increment was positively correlated with the thinning intensity in both experiments. Moreover, increments of diameter, height, basal area, and volume were higher in Maçka-Yeşiltepe experiment than in Vakfıkebir experiment. But, the values of moderate and strong thinning intensities applied in Vakfıkebir were close to each other. When all the results are evaluated, application of strong thinning intensity for Yeşiltepe sample plot, the moderate thinning intensity for Vakfıkebir sample plot is seen appropriate by us in terms of both stand development.
U ovom su istraživanju proučavani učinci prve prorjede različitih intenziteta u plantažnim područjima azijske bukve (
Fagus orientalis
Lipsky) vezano za povećanje promjera i visine stabala. Odabrane su primjerne plohe u plantažnim područjima azijske bukve unutar granica okruga Maçka–Yeşiltepe i Vakfıkebir u pokrajini Trabzon, Turska. Primjerne plohe utvrđene su prorjedom u četiri različita intenziteta (kontrolni, slaba, umjereni, jaka), uklanjanjem 0%, 10%, 25% i 40% temeljnice po hektaru sastojine u fazi mladika. Nakon prorjeđivanja, temeljnica je izračunata mjerenjem promjera i visine stabala u utvrđenim primjernim plohama kako bi se utvrdio rast sastojine. Utvrđeni su učinci prorjede povezani s određenim karakteristikama sastojine (prosječni promjer, temeljnica, prosječna visina, relativni debljinski prirast, itd.) i određenim odabranim stablima. Učinak intenziteta prorjede na prosječni promjer, vrijednost temeljnice i volumena pokazao se kao statistički važan u svakoj od dvije plantaže. Dvogodišnji rezultati pokazali su da je prorjeda značajno povećala debljinski prirast, a povećanje debljinskog prirasta je u pozitivnoj korelaciji s intenzitetom prorjede u oba eksperimenta. Štoviše, prirast promjera, visine, temeljnice i volumena bio je veći u eksperimentu u Maçka-Yeşiltepeu nego u eksperimentu u Vakfıkebiru. Međutim, vrijednosti umjerenog i jakog intenziteta prorjede u Vakfıkebiru bile su bliske. Nakon procjene svih rezultata, smatramo da je primjena jakog intenziteta prorjede u primjernoj plohi u Yeşiltepeu i umjerenog intenziteta prorjede u primjernoj plohi u Vakfıkebiru prikladna u smislu razvoja sastojine.
Cilj istraživanja bio je utvrditi utjecaj pasmine i spola svinja na dnevni prirast u testu u proizvodnim uvjetima. Istraživanje je obuhvatilo 62 469 zapisa iz testa svinja u proizvodnim uvjetima od ...1998. do 2017. godine u Republici Hrvatskoj. U istraživanje su bile uključene svinje četiri čiste pasmine: landras (L), veliki jorkšir (VJ), pietren (P), durok (D) te oba recipročna križanca LxVJ. Oba promatrana utjecaja imala su značajan utjecaj (P<0,05) na dnevni prirast. Uočena je statistički značajna razlika u dnevnom prirastu između pasmina. Prosjeci dobiveni metodom najmanjih kvadrata pokazuju da su svinje pasmine durok imale najveći dnevni prirast sa 583 g, zatim ih slijede križanci LxVJ sa 532 g i VJxL sa 529 g. Dnevni prirast za velikog jorkšira iznosi 528 g, a najmanji prirast je zabilježen kod pietrena sa 519 g. Utvrđena je značajna razlika (P<0,05) u dnevnom prirastu u testu u proizvodnim uvjetima između spolova (nerastića i nazimica) gdje prosječni dnevni prirast dobiven metodom najmanjih kvadrata iznosi 569 g u nerastića i 508 g u nazimica.
The paper analyses quantitative and qualitative features of the population of five towns in the Bjelovar-Bilogora County, with the predicted number of inhabitants by 2051. It presents the movement in ...the number of inhabitants in the period 1857–2016, stressing the depopulation processes in the last five decades. Thanks to the industrialisation and deruralisation processes, up to the year 1991, there had been an intensive increase in the number of inhabitants of Bjelovar and Daruvar, while the number of inhabitants in Čazma, Garešnica and Grubišno Polje began decreasing as soon as at the time of the first census following World War Two. Over the last fifty years, the spatial image of the presence of population in the County changed significantly. In comparison with the Croatian average, depopulation processes in rural areas in this area were more intensive. This was confirmed by the analysis of the natural movement of population. As early as in the 1970s, not only all the municipalities, but also urban settlements of the Country entered the post-transitional demographic phase, which was characterised by negative differences between the birth and the death rates, as well as by a negative migration balance. These were the main causes of a nearly dramatic depopulation having taken place in the vast majority of settlements in the County. Furthermore, the aggravation of the age structure of population is directly connected with the aforementioned movements. There is a decrease in the percentage of the young population, whilst the contingent of the old population is in constant increase. The schooling (educational) structure of the population is becoming increasingly favourable, which – in a certain sense – increases the mobility, i.e. stimulates the negative migration balance. If the current trends of population movement (present for the last two decades) are projected into 2051, the number of inhabitants of Bjelovar will – around the mid-21st century – decrease by approximately 25 %, of Čazma by 47 %, of Daruvar by 54 %, of Garešnica by around 63 %, and of Grubišno Polje by nearly 80 %. This is more than likely to initiate extremely negative movements within population aging processes and other qualitative features, accompanied by dramatic demographic vacation of rural areas. Demographic movements of this kind oughtto present the final alarm for the entire society to create and implement a new, long-term demographic and developmental policy.
Prekomjerna težina i debljina se definiraju kao prekomjerno i abnormalno nakupljanje masnoće koje predstavlja zdravstveni rizik. Gotovo trećina žena reproduktivne dobi u svijetu je pretila. Rizici ...pretilosti osobito su izražen u trudnoći jer donose dugoročne zdravstvene probleme, kako za majku, tako i za njeno dijete. U prikazu slučaja je opis trudnice koja je i prije trudnoće imala prekomjernu tjelesnu masu, a u trudnoći je tu masu povećala do stadija pretilosti. Iako nije imala zdravstvene poteškoće tijekom trudnoće, porod je dovršen carskim rezom zbog fetopelvine disproporcije rođenjem makrosomnog djeteta. Postporođajno zadržavanje pretilosti ima svoje rizike, a djeca rođena iz takvih trudnoća imaju povećani rizik da kasnije u životu razviju pretilost i zdravstvene probleme povezane s pretilošću. Prevencijom kroz edukacije i savjetovanje moguće je umanjiti dugoročne rizike debljine žena reproduktivne dobi.
This paper addresses the changes in the number of primary school students in school areas of the Bjelovar-Bilogora County. It thereby tackles demography in general and school demography in ...particular. The author has studied the subject in the context of demographic changes in the Republic of Croatia, and proved that since the early 1960s, there has been a continuous decrease in natural population growth as a consequence of a decreasing birth rate, negative migration rate, and changes in the population structure reflected in a decrease in the young population against an increase in the old population. The war aggression on Croatia (1991–1995) has led to a decrease in the total population number. The author concluded that negative general trends were occurring in all parts of the country (in the counties), causing a decrease in the number of primary school students. On a sample of 26 regular primary schools in the Bjelovar-Bilogora County, the author has studied changes in the number of students between schoolyears 1969-70 and 2018-19, with a particular emphasis on changes in the five school areas. Research results have shown that the number of inhabitants had been reduced by 47,835 (28.6%) between the censuses of 1961 and 2011, which led to a decrease in the number of primary school students by 10,323 (54.9%) in the schoolyear 2018-19 in comparison with the schoolyear 1969-70. General changes related to the population on the whole, as well as the total number of school students, have caused changes – or rather a decrease – in the number of students in all school areas. In the Grubišno Polje school area, the most significant decrease in the number of students in the studied period was recorded – 72.7%. The figures in other school areas are as follows: Daruvar 66.1%; Garešnica 58.1%; Čazma 53.7%; Bjelovar 40.8%. Based on the entrance (number of first-grade students) and the exit (number of eighth-grade students) figures, it has been estimated that the process of the decrease in the number of students will in the forthcoming decade continue – both at the county level and at the level of the five studied school areas.
Cilj istraživanja bio je procijeniti utjecaj različitih razina fitaze izdvojene iz Bacillus sp. (HCYL03) i dodane u obroke od kukuruza i soje kojima se hrane brojleri. Istraživanje je uključilo ...pozitivnu kontrolu (PC) s izračunatom razinom nefitatnog fosfora (nPP) od 4,0 g/kg tijekom 35 dana trajanja istraživanja. Prehrana brojlera u negativnoj kontroli (NC) uključila je smanjenje nPP-a na 3,0 g/kg tijekom trajanja pokusa, komercijalno dostupnu fitazu (@500FTU/kg), kao i novu bakterijsku fitazu dodanu NC prehrani, u količini koja se povećavala na 500, 800 i 1100 FTU/kg. Učinci na rast, probavljivost fosfora, mineralizaciju tibije i razinu kalcija i fosfora u krvnoj plazmi procijenjeni su 35. dan pokusa. U skupini NC smanjeni su unos hrane (P<0,05) i prirast tjelesne mase (BWG) (P<0,05), dok je stopa konverzije hrane povećana (FCR) (P<0,05) u usporedbi sa skupinom PC. Dodatak fitaze pozitivno je utjecao na sve pokazatelje rasta. Brojleri u skupini NC pokazali su manju probavljivost fosfora (P<0,05), smanjenu mineralizaciju tibije (P<0,05) te smanjenu količinu fosfora i kalcija (P<0,05) u krvnoj plazmi u usporedbi s brojlerima iz skupine PC. Utvrđeno je da dodatak fitaze poboljšava probavljivost fosfora, mineralizaciju tibije i sadržaj minerala u krvnoj plazmi. Dodatak veće količine fitaze (1100 FTU/kg) rezultirao je najvećim poboljšanjem u istraženim svojstvima brojlera, probavljivosti hrane i mineralizaciji kosti u skupini NC. Zaključeno je da bi se anorganski fosfor uključen u uobičajenu nPP prehranu pilića mogao učinkovito zamijeniti Bacillus sp. (HCYL03) fitazom, bez štetnih učinaka na prehranu i svojstva brojlera.
Cilj ovoga istraživanja bio je ispitati učinak hranidbe uz dodatak propolisa i/ili pčelinjega peluda na proizvodne pokazatelje brojlera. Ovaj pokus proveden je na 200 brojlera provenijencije Ross 308 ...ravnomjerno raspoređenih po spolu, koji su bili podijeljeni u pet skupina. Tijekom cijeloga pokusa kontrolna je skupina brojlera bila hranjena krmnom smjesom, dok su pokusne skupine brojlera hranjene istom krmnom smjesom uz dodatak propolisa i pčelinjeg peluda, svakim dodatkom zasebno ili u kombinaciji u određenome omjeru. Prosječne vrijednosti tjelesne mase brojlera bile su znatno više 7. (p=0,001), 14., 21., 28., 35. (p<0,001) i 42. (p=0,002) dana tova u pokusnim skupinama brojlera u usporedbi s kontrolnom skupinom. Prosječne vrijednosti prirasta bile su znatno više 1. (p<0,001), 2. (p=0,002), 3. (p< 0,001), 4. (p= 0,029) i 5. (p=0,009) tjedna tova u pokusnim skupinama brojlera u usporedbi s kontrolnom skupinom. Ovo istraživanje je nedvojbeno pokazalo kako propolis i pčelinji pelud imaju značajan pozitivan učinak na proizvodne pokazatelje brojlera.
The main goals of these investigations were to explore possibilities for therapy of sows suffering from puerperal endometritis by intra uterine application of sterile mannan-oligosaccharide (MOS) ...suspension and to compare obtained results with standard therapy with Lotagen (Byk Gulden, Germany). Mannan-oligosaccharides are prebiotics that may prevent bacterial adhesion to mucosal surfaces and to neutralize their toxins without causing tissue damage. It was postulated that this therapeutical approach may result in successful curing of diseased sows, lower percent of recidivism and positive effects on piglet’s growth due to improved milk production. A trial was conducted on four experimental and one control group of sows consisting of 10 animals each. Experimental groups were formed of sows with purulent vaginal discharge 2-3 days post farrowing along with reduced apatite. Animals were fed standard food mixtures (AOC Tables, 1993). Clinical examination was performed on the day of therapy and 2-5 days latter. Uterus content samples for bacteriological and cytological examination were collected on the day of first clinical examination and immediately after that, sterile MOS suspension or Lotagen were administered by means of catheter. After 2-5 days, a second sampling was performed. We have used MOS-based product (Yeast Call Wall, Batch No 6.9.175, Alltech, Fermin, Senta) in the amounts of 5, 10 and 20g (I, II and III group) suspended in 100ml of saline. Sows from the group IV were treated in the same way by 100ml of 2% Lotagen solution. Smears for cytological analyses were stained by May-Grunwald Giemsa method and analyzed by means of direct light microscopy (Olympus BH-2, Japan), using immersion objective and at total magnification of 1000 X. We have determined presence of neutrophylles, eosinophylles, lymphocytes, monocytes, epithelial cells and bacteria as well as their structure. Bacteriological examination was performed by standard plating procedures on Columbia agar (CM331, Oxoid, Basingstoke, UK) with addition of 5% ovine blood and MacConkey agar (CM115, Oxoid). Plates were incubated in aerobic conditions at 37 0C over 24-48hrs. Isolated bacteria were multiplied in pure culture on CM3 agar (Oxoid) and identification was performed on the basis of colony morphology, microscopic appearance, catalase and oxidase tests and biochemical characteristics. A total number of aerobic, mesophyllic bacteria was determined by ten folds serial dilutions (10 - 105) in buffered peptone solution (CM1049, Oxoid). Samples of 0.5 ml were inoculated in sterile Pasteur plates and then covered with Tryptone soya agar (CM131, Oxoid) with addition of 5% ovine erythrocytes. Plates were again incubated at 37 0C over 48hrs and grown colonies were counted in plates containing 30-300 colonies to estimate number of CFU (Colony Forming Unites). Piglets from each litter were weighed individually on the day of sow´s therapy, 2-5 days latter at control examination and at the moment of weaning in order to calculate total and daily body weight gains. Body weight was measured by electronic scale with sensitivity of 10 g. In the last trial phase, reproductive results of sows were determined in their next breeding cycle. We have recorded a total number of piglets born, number of alive and stillborn and percent of piglet’s loss after 3 days post farrowing. Statistical analyses were performed by calculating standard descriptive parameters: mean values, standard deviations and variation coefficient. Statistical significance of differences was estimated using Student´s t test. Treatment of sows with puerperal dysgalactia by intrauterine application of MOS suspension resulted in significant clinical improvement and percent of recidivism was the smallest in groups treated with 10 and 20g. On the stained smears of uterine content a presence of neutrophylles, eosinophylles, lymphocytes, monocytes, epithelial cells and bacteria was noted. In all experimental groups, very highly significant differences were present between mean number of neutrophylles at the moment of therapy and 2-5 days later. The best effects in therapy were achieved by 10 and 20g of MOS suspended in 100ml of saline. Following treatment, highly significant differences were noted between groups treated with 5g and 10g and 20g. Differences between groups treated with Lotagen and those treated with 10 and 20g of MOS were very highly significant. Degree of bacterial colony number reduction was the highest in groups treated by intrauterine application of 10 and 20g of MOS ranging from 1361 to 1444 times. In the sows treated with Lotagen solution this value was 32. The most abundant bacterial species isolated from sow’s uterine content were: E. coli, Streptococcus dysgalactiae subspecies equisimilis, Staphylococcus aureus, Arcanobacterium pyogenes and coagulase negative Staphylococcus. At the moment of weaning, piglets from the groups of sows treated with 10 and 20g of MOS were heavier then the piglets from the control and Lotagen treated group of sows. Treatment of sows with PDS by intra uterine application of MOS suspension and Lotagen did not significantly influenced number of piglets born in the next reproductive cycle and between experimental groups no statistically significant differences were noted. A total piglet´s loss during first days of life was the highest in the control group. Treatment of sows with PDS by intra uterine application of MOS suspension resulted in significant clinical improvement with small percent of recidivism and exerted positive effects on piglets body weight gain up to the moment of weaning.
Osnovni cilj ovog istraživanja je bio da se ispita mogućnost terapije puerperalnih endometrita krmaca, intrauterinom aplikacijom sterilne suspenzije manan-oligosaharida (MOS) i uporede dobijeni rezultati sa rezultatima klasicne terapije primenom metakrezol sulfonske kiseline sa metanolom (Lotagen, Byk Gulden, Germany). Mananoligosaharidi su prebiotici koji imaju sposobnost da spreče adherenciju patogenih bakterija za površinu sluzokože, kao i da neutrališu njihove toksine, a da pri tome ne oštete tkivo. Postavljena je pretpostavka da je moguće izlečenje krmača obolelih od endometritisa nakon prašenja uz manji procenat recidiva i ispoljavanje pozitivnih efekata na prirast prasadi usled blagovremene normalizacije produkcije mleka. Ispitivanje je izvedeno na 4 ogledne i jednoj kontrolnoj grupi krmača sa po 10 plotkinja u svakoj. Ogledne grupe su sačinjavale krmače kod kojih je 2 -3 dana po prašenju, uočen purulentni vaginalni iscedak i koje imaju smanjen apetit. Plotkinje su bile hranjene prema standardnim normativima (AOC tablice, 1993). Klinička procena zdravstvenog stanja krmača je vršena na dan terapije i nakon 2-5 dana. Od krmača oglednih grupa su prikupljani uzorci sadržaja uterusa za citološka i mikrobiološka ispitivanja, a neposredno posle toga vršena je jednokratna aplikacija sterilne suspenzije MOS preparata ili Lotagena. Posle 2-5 dana, uziman je kontrolni ispirak. Za terapiju je korišćen preparat na bazi manan-oligosaharida (YCW – Yeast Cell Wall, Alltech, Fermin, Senta) u količinama od po 5, 10 i 20 grama (prva, druga i treća grupa) suspendovanog u 100ml fiziološkog rastvora. Plotkinjama četvrte grupe je aplikovan Lotagen (Byk Gulden, Germany), u kolicini od 100ml i koncentraciji od 2 %. Preparati za citološke analize su bojeni metodom May-Grunwald Giemsa, a njihova analiza je vršena metodom direktne svetlosne mikroskopije pomoću mikroskopa Olympus BH-2, (Japan) imerzionim objektivom na ukupnom uvećanju od 1000 x. Određivano je prisustvo neutrofilnih i eozinofilnih granulocita, limfocita, makrofaga, epitelnih ćelija i bakterija, kao i njihova struktura. Bakteriološko ispitivanje je izvedeno standardnom mikrobiološkom tehnikom na Columbia agar (CM331, Oxoid, Basingstoke, UK) sa dodatkom 5% ovčije krvi i MacConkey agar (CM115, Oxoid). Ploče su inkubirane u aerobnim uslovima na temperaturi od 37ºC, tokom 24-48h. Izolovane bakterije su zatim umnožene u čistoj kulturi na hranljivom agaru (CM3,Oxoid), a identifikacija izolata izvedena je na osnovu morfologije kolonija, mikroskopskog izgleda, testova katalaze i oksidaze i ispitivanja biohemijskih karakteristika. Ukupan broj aerobnih, mezofilnih bakterija određivan je pripremom desetostrukih razređenja uzoraka (10 -105) u puferovanoj peptonskoj vodi (CM1049, Oxoid). U količini od 0.5 ml, razređenja uzoraka su inokulisana u sterilne Petri ploče i zalivena sa Tryptone soya agar (CM131, Oxoid) sa dodatkom 5% ovčijih eritocita. Ploče su inkubirane na 37 oC tokom 48h. temperaturi od 37 oC, tokom 24-48h. Izolovane bakterije su zatim umnožene u čistoj kulturi na hranljivom agaru (CM3,Oxoid), a identifikacija izolata izvedena je na osnovu morfologije kolonija, mikroskopskog izgleda, testova katalaze i oksidaze i ispitivanja biohemijskih karakteristika. Ukupan broj aerobnih, mezofilnih bakterija određivan je pripremom desetostrukih razređenja uzoraka (10 -105) u puferovanoj peptonskoj vodi (CM1049, Oxoid). U količini od 0.5 ml, razređenja uzoraka su inokulisana u sterilne Petri ploče i zalivena sa Tryptone soya agar (CM131, Oxoid) sa dodatkom 5% ovčijih eritocita. Ploče su inkubirane na 37 oC tokom 48h. Posle isteka perioda inkubacije prebrojane su izrasle kolonije na pločama sa 30-300 kolonija i određen je kupan broj bakterija (CFU/ml). Prasad iz svakog legla je merena pojedinačno: na dan terapije krmača, 2-5 dana kasnije (pri kontrolnom pregledu) kao i u momentu zalučivanja radi izračunavanja ukupnih i dnevnih prirasta. Telesna masa prasadi je merena elektronskom vagom sa tačnošću od 10g U poslednjoj fazi ogleda su analizirani reproduktivni rezultati krmača, koje su bile uključene u ogled, u narednom ciklusu. Registrovan je broj ukupno oprašene prasadi, živorođene i mrtvorođene kao i procenat gubitaka tokom prva tri dana po prašenju. Statistička analiza je vršena izračunavanjem uobičajenih deskriptivnih parametara: srednje vred
Carp is cultured in all the 3 systems: extensive, semiintensive and intensive. Contrary to extensive rearing where weight gain depends exclusively on natural food, semiintensive and intensive systems ...are based on partial or complete reliance on added feed. During the rearing season the natural food in fish ponds with the semiintensive system has a prominent seasonality: in the period of natural food depression with optimal temperatures for carp growth (from mid June to the end of August) weight gain is primarily dependent on the quality and quantity of added feed. From an economical, and also an ecological point of view it is important to supply feed that will meet nutritional requirements of fish, and result in low feed conversion coefficient, high growth rate, good health condition, high quality of the final product – fish meat, and as low as possible load of the aquatic environment with organic matter, phosphorus, and nitrogen. Nutritional properties of fish feed are highly dependent on the protein and fat level. It is of utmost importance to stress that the amount of basic components in feed should not be fewer than the requirements of farmed fish, though, particularly from the economic point of view, this amount should’t be too high since the fish will not be able to utilise it. As the main building blocks, proteins are essential for body growth and a number of physiological processes. Their origin and quantity in feed mixtures are of crucial importance for the utilization of feed and growth of cultured fish. Fishmeal is the most desirable component of the feed that provides proteins with good amino acid composition in feed for carnivorous fish species, as well as for omnivorous fish in intensive production. Due to the deficit of this very important nutrient at the world market and their high prices, fishmeal and other feed of animal origin are combined or replaced with alternative sources of plant proteins. There is a constant tendency towards decreasing the share of fishmeal in feed while optimizing the amount of proteins in the meal. Fat in feed contribute to better utilization of proteins from the meal, preventing its use as a source of energy. Within certain limits, an increasing level of lipids in the diet results in improved feed efficiency, providing biologically useful energy and thus saving proteins. However, fish are able to utilize lipids in food to some extent, above which it may cause reduced growth, lowered food consumption and formation of body fat. Feeding carp with a higher content of fat in a diet, the final product is of poor quality, since its level significantly affects the texture and consistency of fish meat. Therefore, the aim of this study was based on a ninety-day examination of feed with different level of protein (38,1%, 38,5%, 41,5% and 43,7%) and feed with different level of fat (8%, 12% and 16%), on growth rate and feed utilization of one-year-old carp fry (Cyprinus carpio). The experiment was carried out under controlled conditions of the Laboratory for Fish Nutrition, University of Belgrade, Faculty of Agriculture. Plastic tanks with a volume of 120 L and water flow of 0.34 Lmin-1 were stocked with 24 fish with an average weight of 95 g (in the experiment with different levels of proteins), and 29 fish fry with an average weight of 15,4 grams (in the experiment with different levels of fat). In the experiments physical and chemical water properties (temperature, oxygen concentration, saturation, conductivity and pH), quantity of consumed feed, fish body dimensions were measured and samples of liver and distal intestine as well as feces were collected. By the calculation of available data, obtained by control measurements in 30 days intervals, statistical analysis showed differences between fish from different treatments. Fish fed on a diet dominated by fishmeal and the total protein content of 43.7%, achieved the greatest growth rate and improved the feed utilization. Fish fed on the diets with 41.5% protein and an equal proportion of fishmeal and full fat soybean meal in the mixture, had better feed utilization and greater weight gain than fish fed on mixtures with the highest amount of soybean meal and lower content of total proteins. Feeding fish with 8% fat in the diet, achieved significantly better production results and better feed efficiency compared to fish fed on diets with a higher fat content. The digestability of proteins from mixtures significantly increased with increased protein share in feed, while digestibility of fat in mixtures was significantly better with the decrease of fat content. Mostly normal histological structure of carp internal organs was observed. In fish fed higher fat content (12 and 16%) in the dietlarge fat cells have been observed in the pancreatic tissue. Moreover early signs of cirrhosis have been observed in fish fed mixture containing 16% fat. The obtained results indicate that in addition to the protein level, their origin and the presence in the mixture significantly affected feed utilization and growth of cultivated fish. Also, it can be concluded that lower levels of fat in carp feed is more justifiable from, both economic and consumer aspects.
Šaran se gaji u sva tri sistema gajenja: ekstenzivni, poluintenzivni i intenzivni. Za razliku od ekstenzivnog gde prirast ribe isključivo zavisi od prirodne hrane, poluintenzivni i intenzivni sistemi su bazirani na delimičnoj ili potpunoj zavisnosti od dodatne hrane. Kako tokom sezone gajenja, prirodna hrana u ribnjacima sa poluintenzivnim sistemom ima veoma izražen sezonalni karakter, u periodu sa optimalnim temperaturama za rast šarana (od sredine juna pa do kraja avgusta) prirast je u najvećoj meri zavistan od kvaliteta i količine dodatne hrane. Sa ekonomskog, ali i ekološkog aspekta važno je obezbediti hranu koja će zadovoljiti nutritivne potrebe riba, rezultirati niskim koeficijentom konverzije, visokim tempom rasta, dobrim zdravstvenim stanjem gajenih riba, visokim kvalitetom finalnog proizvoda, odnosno ribljeg mesa i što manjim opterećenjem vodene sredine organskim materijama, fosforom i azotom. Nutritivna svojstva hrane za ribe u velikoj meri zavise od udela proteina i masti. Veoma je važno da osnovnih komponenti u hrani za ribe ne bude manje od potreba gajenih riba, ali i sa ekonomskog aspekta da ih u hrani ne bude više od količine koju ribe mogu iskoristiti. Proteini kao gradivne komponente, su veoma važni za izgradnju tela ali i za brojne fiziološke procese u organizmu. Njihovo poreklo, sastav, kao i količina u smešama od presudnog su značaja za iskoristivost hrane i prirast gajenih riba. Najpoželjnija komponenta, kao nosilac proteina odgovarajućeg aminokiselinskog sastava, za proizvodnju hrane za karnivorne vrste riba, ali i za intenzivno gajenje omnivornih riba je riblje brašno. Zbog deficita ovog veoma važnog hraniva na svetskoj pijaci i visoke cene na tržištu, riblje brašno, kao i ostala hraniva animalnog porekla se kombinuju ili pak potiskuju sa alternativnim biljnim izvorima proteina, uz optimizaciju količine u obroku i uz stalnu težnju da se što veći procenat ribljeg brašna potisne iz hrane. Masti prisutne u hrani doprinose efikasnijem iskorišćavanju proteina iz obroka, zahvaljujući čemu se skuplji proteini čuvaju od neracioanlnog iskorišćavanja kao dodatni izvor energije. U okviru određenih granica, povećanje nivoa lipida u obroku, dovodi do poboljšanog iskorišćavanja hrane, tako što se lipidi koriste za obezbeđivanje biološki korisne energije i na taj način se štede proteini. Međutim, ribe su u stanju da koriste lipide u hrani do određenog nivoa, nakon čega može doći do redukovanog rasta, smanjene potrošnje hrane i stvaranja masnih naslaga u telu. Pri ishrani šarana sa većim sadržajem masti u obroku, kao finalni proizvod dobija se meso lošijih senzornih karakteristika, jer nivo masti značajno utiče na teksturu ribljeg mesa i njegovu konzistenciju. Zbog svega navedenog, cilj ovog istraživanja zasnivao se na 90–to dnevnom ispitivanju smeša sa različitim učešćem ukupnog sadržaja proteina (38,1%, 38,5%, 41,5% i 43,7%) i smeša koncentrata sa različitim učešćem masti (8%, 12% i 16%), na prirast i iskoristivost hrane kod jednogodišnje mlaĊi šarana (Cyprinus carpio). Eksperiment je realizovan u kontrolisanim uslovima Laboratorije za ishranu riba, Univerziteta u Beogradu–Poljoprivrednog fakulteta. U plastične tankove zapremine 120 l sa konstantnim protokom 0,43 l/min, nasađeno je po 24 jedinki prosečne mase 95 grama (u eksperimentu sa proteinima), odnosno po 29 jedinki šaranske mlaĊi prosečne mase 15,4 grama (u eksperimentu sa mastima). Tokom eksperimenta merene su fizičke i hemijske osobine vode (temperatura, koncentracija kiseonika, zasićenje vode kiseonikom, elektroprovodljivost i pH), količina pojedene hrane i telesne dimenzije riba, a uzeti su uzorci organa za histologiju kao i uzorci fecesa. Obračunom raspoloživih podataka, dobijenih kontrolnim merenjima u 30-to dnevnim intervalima i statističkom analizom je utvrđeno da postoje razlike kod riba iz različitih tretmana. Ribe hranjene smešama gde dominira riblje brašno i sa ukupnim sadržajem proteina od 43,7%, ostvarile su najveći prirast i bolju iskoristivost hrane. Ribe hranjene smešama sa 41,5% proteina i jednakim udelom ribljeg brašna i punomasnog sojinog griza u smeši, imale su bolju iskoristivost hrane i veći prirast, nego ribe hranjene smešama u kojima je dominirao sadržaj sojinog griza sa nižim sadržajem ukupnih proteina. Upotrebom smeša koncentrata sa različitim učešćem masti, statistički vrlo značajno su postignuti bolji proizvodni rezultati, bolja iskoristivost i efikasnost hrane, ishranom riba smešama sa 8% masti nego ako su ribe hranjene smešama sa većim sadržajem masti. Svarljivost proteina iz smeša koncentrata je bila statistički vrlo značajno veća kako se udeo proteina provećavao, dok je svarljivost masti iz korišćenih smeša bila statistički značajno bolja kako se udeo masti smanjivao. Histološkom analizom u
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