41 research outputs found
Kolaps ribarstva na Dojranskom jezeru ā razlozi i perspektive
U radu je prikazano stanje ribarstva na Dojranskom jezeru, starom vodenom basenu na granici Republike Makedonije i GrÄke. Pored statistiÄkih podataka o komercijalnom ulovu od 1946. predstavljena je i njihova komparativna analiza koja pokazuje da se sastav riblje zajednice Dojranskog jezera drastiÄno promenio. GodiÅ”nji ulov ribe u poslednje dve dekade pokazuje trend neprekidnog opadanja Å”to se odrazilo na sastav vrsta u ulovu. Opada ulov vrsta C. carpio, S. glanis i P. fluviatilis, dok ulov vrste C. gibelio pokazuje snažan trend rasta posle njene introdukcije. Analizirani su statistiÄki podaci o ulovu ribe od 1946. i uporeÄeni su sa podacima o nivou vode u jezeru od 1951. UoÄene su brojne Äinjenice koje dovode u vezu koliÄinu vode u jezeru i izlov ribe i pritom ukazuju da sadaÅ”nji nivo vode u jezeru može usloviti prekid komercijalnog ribolova. Promenjiv nivo vode u jezeru ubrzava proces eutrofikacije Å”to se negativno odražava na kvalitet vode
INTERAKCIJE GENOTIP X SUSTAVA HRANIDBE KOD MASE MESA OSNOVNIH DIJELOVA TRUPA BROJLERSKIH PILIA
This paper examines genotype x diet interactions with meat mass of main carcass parts (breast, drumstick and thigh) in broiler chickens. The study was conducted in chickens of proveniences Cobb 500 and Hubbard Classic, which were fed variety of energy - protein feed mixtures (mixture I āenergy stronger with higher E:P ratio and mixture II ā protein stronger with lower E:P ratio). Chickens were fattened to 49 days of age. Randomly selected chickens were sacrificed and processed in dressing percentage "ready for grilling" at the end of 35th, 42nd and 49th day of age. Each carcass was separated at the most important edible parts. Their yields and share were determinate and put in relationship with body weight before the slaughtering. The existence of interactions was confirmed in chickens of same age, the analysis of variance in Statistic computer program, subprogram ANOVA, while the definition of treatments where interaction appeared was proven by LSD test at the level of 0.01% accuracy. Genotypes x diet interactions were demonstrated in all age groups only in the analysis of breast meat mass. Cobb chickens fed mixture I on 42nd and 49th days of age and those fed mixture II on 35th day of fattening had significantly more breast meat than Hubbard chickens. The interaction in mass of drumstick meat was proven on 35th day of age, while in mass of thigh meat it was demonstrated in the last week of fattening. Cobb chickens fed protein stronger meal had significantly more meat on drumstick, while chickens fed energy stronger mixture appeared to have more mass of meat on thigh. Hubbard chickens that used mixture II had insignificant greater mass of meat in most important parts of carcass during the 35th and 42nd days of fattening. Genotype x diet interactions are responsible for no more than 2% of the total variations, but although the influence is rather weak, they should be implemented in most of the analyses.U ovom se radu razmatra interakcija genotip x sustava hranidbe kod mase mesa važnijih dijelova trupa (prsa, bataka i zabataka) kod brojlerskih piliÄa. Ispitivanje je provedeno kod piliÄa provenijencije Cobb 500 i Hubbard Classic koji su hranjeni razliÄitim energetsko - proteinskim krmnim smjesama (smjesa I - energetski jaÄa i s veÄim odnosom E:P i smjesa II - proteinski jaÄa i s manjim odnosom E:P). PiliÄi su tovljeni 7 tjedana i krajem 5, 6 i 7 tjedna sluÄajno odabrani piliÄi su žrtvovani i obraÄeni randmanom āpripremljeno za roÅ”tiljā. Svakom trupu izdvojeni su najvažniji jestivi dijelovi, utvrÄeni su njihovi prinosi i udjel, stavljeni u odnosu na živu masu piliÄa prije klanja. Postojanje interakcija je provjereno kod piliÄa istog uzrasta, analizom varijance u kompjutorskom programu Statistica, pod program Anova, dok se definiranje tretmana kod kojih se pojavila interakcija dokazivalo LSD testom na razini 0,01% toÄnosti. Interakcije genotip x hranidba ispoljile su se u svim uzrastima jedino kod analize mase prsnog mesa. PiliÄi genotipa Cobb hranjeni smjesom u sustavu I 42 i 49 dana i smjesom u sustavu II 35 dana tova imali su znaÄajno viÅ”e prsnog mesa u odnosu na piliÄe Hubbard. Kod mase mesa bataka interakcije su dokazane u dobi od 35 dana, dok su se kod mase mesa zabataka ispoljile u zadnjem tjednu tova. PiliÄi Cobb, koji su uzimali krmnu smjesu u sustavu II imali su znaÄajno viÅ”e mesa na batacima, dok su se kod piliÄa hranjenih krmnom smjesom u sustavu I pojavile veÄe koliÄine mesa na zabatcima. Hubbard piliÄi koji su uzimali proteinski jaÄu smjesu imali su neznaÄajno veÄu masu mesa važnijih dijelova trupa u 35 i 42 danu tova. Interakcije genotip x hranidba, odgovorne su za ne viÅ”e od 2% ukupnih varijacija, ali iako je uÄinak priliÄno slab, njega treba primjenjivati u veÄini analiza
PRVI NALAZ VRSTE Acerina cernua Linnaeus, 1758 U VODAMA REPUBLIKE MAKEDONIJE
This paper describes the general importance of this fish species and deals with its first registration in the waters of Macedonia in 1997. Its basic ichthyological parameters are presented, as well as the ichthyofauna of the reservoir where it was found. Based on available data it was tried to trace the origin of this species in Macedonia.U radu se iznosi opÄi znaÄaj ove vrste riba, te navodi njezin prvi nalaz u Makedoniji godine 1997. Daje se njezin osnovni ihtioloski opis, te navodi ihtiofauna akumulacije u kojoj je naden. Na temelju dostupnih podataka pokuÅ”ava se analizirati moguÄi put ulaska ove riblje vrste u vode u Makedoniji
Pattern formation during electrodeposition of copper-antimony alloys
Aim of the present study is to establish the conditions of the electrolysis for the preparation of structured and unstressed purple-pink coatings of copper-antimony alloys, including their phase characterization. Also the task of the present investigation is, by changing drastically the metal content in the methanesulfonic electrolyte to find out the conditions of electrolysis where the self-organization of the different phases is expressed by higher-order structures - not only waves but also spirals and targets. The possibility to obtain copper-antimony alloy with up to 80 wt. % Sb from methanesulfonic acid is shown. The deposition rate, morphology and the phase composition of the obtained coatings are established. The phenomena of formation of spatio-temporal structures in this alloy are described.It is determined that the observed structures consist of Cu2Sb and Cu11Sb3 intermetallic phases
Longitudinal classification of the river Vardar based on the heavy metal content in the muscles of Barbus peloponnesius L.
EXAMINATION OF CONTENT OF HEAVY METALS AND PESTICIDES IN FISH IN THE ACCUMULATION STREZEVO IN THE REPUBLIC OF MACEDONIA
Abstract In the period from 2007 to 2009 th year, the heavy metal concentration (Pb, Cd,? s? Hg
Primjena genetskih algoritama za utvrÄivanje parametara asinkronog motora
An approach is presented for determining the equivalent circuit parameters of squirrel cage induction motors by genetic algorithms. An equivalent circuit without considering the steel losses is analyzed. The sensitivity of the approach is discussed by using one, two and three sets of data. The accuracy of the proposed approach is analyzed by determining the relative error in the parameters, obtained by genetic algorithms, with regard to analytical values.Predstavljen je pristup za utvrÄivanje nadomjesnih parametara strujnog kruga kaveznog asinkronog motora pomoÄu genetskih algoritama. Analizirano je nadomjesno strujno kolo bez razmatranja gubitaka u Äeliku. Razmotrena je osjetljivost pristupa uporabom jednog, dva i tri niza podataka. ToÄnost predloženog pristupa je analizirana pomoÄu odreÄivanja relativne pogreÅ”ke u parametrima, dobivene genetskim algoritmima, u odnosu na analitiÄke vrijednosti
Fish as a health food ā ecotoxicological viewpoint
Fish body metal (Cd, Pb, Zn, Cu, Al, Cr, Ni, Fe, Mn, Sr, Co) contents measurements, target organ and tissue distribution pattern analysis, bioaccumulation and biomagnification studies have been undertaken on a wide range of fish species belonging to various trophic levels within fish community from the Tikvesh reservoir in the R. Macedonia. The results of the current study indicated liver, kidney and gonads as target organs for metal accumulation and muscles as the tissue with the lowest concentrations of metal residues. Fish caught throughout 2006-2008 in the investigated area could be recommended as health food concerning metal burden as Macedonian alimentary standards for Cd and Pb in edible tissues have not been exceeded
EFFECTS OF DIFFERENT SUPPLEMENTS INCLUSION OF THE ENRICHED DIET ON PRODUCTIVE PERFORMANCE AND EGG STRUCTURE
Nutritional manipulation and genetic selection for egg size and production may lead to changes in egg components. This experiment was carried out to analyze the egg structure parameters of eggs produced by Hisex Brown laying hens fed with diet with different supplements inclusion. The intensity of egg production was significantly higher in the groups fed with enriched feed with iodine (90.00%), vitamin E (90.00%) and selenium (91.98%), and significantly lower in the group fed with DHA inclusion feed (76.00%) in respect to the control group (82.00%), confidence interval of 95%. Concerning diet supplemented with selenium and diet supplemented with vitamin E, the egg yolk weight was statistically different compared with the control group (confidence interval of 95%). The yolk weight averaged 1.80 g and 1.29 g more than yolk weight in the control eggs, respectively. The egg shell weight was statistically different in diet enriched with iodine compared with the control. The egg shell weight averaged 1.48 g less per egg for the eggs enriched with iodine with 17.45% less underweight than the control eggs. Enriched eggs offer consumer a variety of value-added options for their egg purchase. Although enriched eggs may provide consumers with a specific quality attribute or healthful ingredient, they do not appear to provide quality and value in a traditional sense as defined by the standards of quality and grade