The North American catfish – the black bullhead, Ameiurus melas (Rafinesque, 1820) is recorded fo... more The North American catfish – the black bullhead, Ameiurus melas (Rafinesque, 1820) is recorded for the first time in the Republic of Macedonia, in Pčinja River. Nine individuals of this ictalurid fish species were fished from the anglers in Pčinja River on September 2015 and another 8 samples on May 2016 were brought to the Institute of Biology, Faculty of Natural Science and Mathematics in Skopje. After a detailed observation of the external morphological features, osteology architecture, it was concluded that analysed individuals had all the distinguishing features of the species A. melas. The presence of different size class permitted the supposition that the black bullhead has established a selfsustaining population in this river.
Background and purpose: Pigmented macrophage aggregates (PMAs) are a part of the immune system of... more Background and purpose: Pigmented macrophage aggregates (PMAs) are a part of the immune system of fish and are considered as valuable biomarkers of the impact of water pollution on fish health.Materials and methods: Immunomodulatory effect of water contaminated with high levels of metals on spleen and splenic PMAs of Vardar chub (Squalius vardarensis) (n=129) was examined in two seasons, spring, and autumn 2012. For this purpose, three rivers were chosen: the Zletovska River, heavily contaminated with metals, the Kriva River, moderately contaminated with metals combined with high level of organic matter, and the Bregalnica River, without heavy metal contamination. Spleen masses and splenosomatic indices (SSI) were used for determining the general impact of water contamination on the immune system of Vardar chub. Moreover, volumes and numbers of PMAs within spleen tissue were determined stereologically.Results: The isolated effect of high exposure to metals caused the reduction of sp...
The validity of four gudgeon species known for the ichthyofauna of North Macedonia has been a mat... more The validity of four gudgeon species known for the ichthyofauna of North Macedonia has been a matter of different taxonomic disputes (except for Gobio ohridanus Karaman, 1924). Recently, a restoration of the species status was proposed for Gobio balcanicus Dimovski et Grupče, 1977 and Romanogobio banarescui (Dimovski et Grupče, 1974). So far, Romanogobio stankoi (Karaman, 1974), has not been a part of any recent investigation and it is still considered as a junior synonym of Romanogobio elimeius (Kattoulas, Stephanidis et Economidis, 1973) or R. banarescui due to the lack of distinctive morphological characters. The osteological characters in the structure of the vertebral column, have significance to the systematics of the gudgeons, especially in elevation of Romanogobio at the level of genus. To contribute to resolving the taxonomic status in these gudgeon species, the goal of this paper is to identify distinctive characters by presenting and analyzing the structure of their verte...
This paper examines genotype x diet interactions with meat mass of main carcass parts (breast, dr... more 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 – energy stronger with higher E:P ratio and mixture II – 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 35, 42 and 49 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% acc...
Isoflavones are phytoestrogens which have estrogen-like activity in animals and humans with struc... more Isoflavones are phytoestrogens which have estrogen-like activity in animals and humans with structure similar to 17-β-estradiol and capable of binding to estrogen receptors (ERs).This experiment was conducted to demonstrate the effect of isoflavones on estradiol concentration in blood and its influence on the productive performances in ISA Brown laying hens fed with supplemented feed with large amount of isoflavones. Isoflavones as non steroid phytoestrogens were added in large amounts to the feed of laying hens in 0, 1000, 2000 and 3000 mg kg-1 of feed. Estradiol concentration in blood of the isoflavone-treated chickens was significantly higher in comparison with the control group (P<0.01). The supplemented isoflavones in the feed have significant improvement on the egg weight during the 1st month (P<0.05) and 2nd month (P<0.01) and also for the whole experimental period (P<0.05). Further studies are required to investigate the effect of isoflavones on other reproductiv...
Metalotioneini (MT) su citosolski proteini odgovorni za homeostazu esencijalnih metala, poput Zn ... more Metalotioneini (MT) su citosolski proteini odgovorni za homeostazu esencijalnih metala, poput Zn i Cu, i detoksikaciju neesencijalnih metala, poput Cd. Cilj ovoga istraživanja bio je potvrditi vezanje ova tri metala na MT u citosolu jetre vardarskog klena (Squalius vardarensis Karaman) uzorkovanog u listopadu 2012. godine u Krivoj reci, oneciscenoj rudarskim otpadom, u sjeveroistocnoj Makedoniji. Primijenjeni analiticki pristup sastojao se od sljedecih koraka: (1) usporednog frakcioniranja citosolskih proteina iz jetre klena i standarda MT na osnovu njihove molekulske mase primjenom visokodjelotvorne tekucinske kromatografije s iskljucenjem po velicini (SE-HPLC), koje je bilo praceno određivanjem koncentracija odabranih metala u tako dobivenim proteinskim frakcijama pomocu spektrometra masa s induktivno spregnutom plazmom (ICP-MS) ; (2) frakcioniranja proteina prema molekulskoj masi pomocu ultrafiltera, sa svrhom odvajanja proteina molekulske mase >30 kDa, koje je bilo praceno da...
U radu je prikazano stanje ribarstva na Dojranskom jezeru, starom vodenom basenu na granici Repub... more U radu je prikazano stanje ribarstva na Dojranskom jezeru, starom vodenom basenu na granici Republike Makedonije i Grčke. Pored statističkih podataka o komercijalnom ulovu od 1946. predstavljena je i njihova komparativna analiza koja pokazuje da se sastav riblje zajednice Dojranskog jezera drastično promenio. Godišnji ulov ribe u poslednje dve dekade pokazuje trend neprekidnog opadanja što 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 statistički podaci o ulovu ribe od 1946. i upoređeni su sa podacima o nivou vode u jezeru od 1951. Uočene su brojne činjenice koje dovode u vezu količinu vode u jezeru i izlov ribe i pritom ukazuju da sadašnji nivo vode u jezeru može usloviti prekid komercijalnog ribolova. Promenjiv nivo vode u jezeru ubrzava proces eutrofikacije što se negativno odražava na kvalitet vode
The North American catfish – the black bullhead, Ameiurus melas (Rafinesque, 1820) is recorded fo... more The North American catfish – the black bullhead, Ameiurus melas (Rafinesque, 1820) is recorded for the first time in the Republic of Macedonia, in Pčinja River. Nine individuals of this ictalurid fish species were fished from the anglers in Pčinja River on September 2015 and another 8 samples on May 2016 were brought to the Institute of Biology, Faculty of Natural Science and Mathematics in Skopje. After a detailed observation of the external morphological features, osteology architecture, it was concluded that analysed individuals had all the distinguishing features of the species A. melas. The presence of different size class permitted the supposition that the black bullhead has established a selfsustaining population in this river.
Background and purpose: Pigmented macrophage aggregates (PMAs) are a part of the immune system of... more Background and purpose: Pigmented macrophage aggregates (PMAs) are a part of the immune system of fish and are considered as valuable biomarkers of the impact of water pollution on fish health.Materials and methods: Immunomodulatory effect of water contaminated with high levels of metals on spleen and splenic PMAs of Vardar chub (Squalius vardarensis) (n=129) was examined in two seasons, spring, and autumn 2012. For this purpose, three rivers were chosen: the Zletovska River, heavily contaminated with metals, the Kriva River, moderately contaminated with metals combined with high level of organic matter, and the Bregalnica River, without heavy metal contamination. Spleen masses and splenosomatic indices (SSI) were used for determining the general impact of water contamination on the immune system of Vardar chub. Moreover, volumes and numbers of PMAs within spleen tissue were determined stereologically.Results: The isolated effect of high exposure to metals caused the reduction of sp...
The validity of four gudgeon species known for the ichthyofauna of North Macedonia has been a mat... more The validity of four gudgeon species known for the ichthyofauna of North Macedonia has been a matter of different taxonomic disputes (except for Gobio ohridanus Karaman, 1924). Recently, a restoration of the species status was proposed for Gobio balcanicus Dimovski et Grupče, 1977 and Romanogobio banarescui (Dimovski et Grupče, 1974). So far, Romanogobio stankoi (Karaman, 1974), has not been a part of any recent investigation and it is still considered as a junior synonym of Romanogobio elimeius (Kattoulas, Stephanidis et Economidis, 1973) or R. banarescui due to the lack of distinctive morphological characters. The osteological characters in the structure of the vertebral column, have significance to the systematics of the gudgeons, especially in elevation of Romanogobio at the level of genus. To contribute to resolving the taxonomic status in these gudgeon species, the goal of this paper is to identify distinctive characters by presenting and analyzing the structure of their verte...
This paper examines genotype x diet interactions with meat mass of main carcass parts (breast, dr... more 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 – energy stronger with higher E:P ratio and mixture II – 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 35, 42 and 49 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% acc...
Isoflavones are phytoestrogens which have estrogen-like activity in animals and humans with struc... more Isoflavones are phytoestrogens which have estrogen-like activity in animals and humans with structure similar to 17-β-estradiol and capable of binding to estrogen receptors (ERs).This experiment was conducted to demonstrate the effect of isoflavones on estradiol concentration in blood and its influence on the productive performances in ISA Brown laying hens fed with supplemented feed with large amount of isoflavones. Isoflavones as non steroid phytoestrogens were added in large amounts to the feed of laying hens in 0, 1000, 2000 and 3000 mg kg-1 of feed. Estradiol concentration in blood of the isoflavone-treated chickens was significantly higher in comparison with the control group (P<0.01). The supplemented isoflavones in the feed have significant improvement on the egg weight during the 1st month (P<0.05) and 2nd month (P<0.01) and also for the whole experimental period (P<0.05). Further studies are required to investigate the effect of isoflavones on other reproductiv...
Metalotioneini (MT) su citosolski proteini odgovorni za homeostazu esencijalnih metala, poput Zn ... more Metalotioneini (MT) su citosolski proteini odgovorni za homeostazu esencijalnih metala, poput Zn i Cu, i detoksikaciju neesencijalnih metala, poput Cd. Cilj ovoga istraživanja bio je potvrditi vezanje ova tri metala na MT u citosolu jetre vardarskog klena (Squalius vardarensis Karaman) uzorkovanog u listopadu 2012. godine u Krivoj reci, oneciscenoj rudarskim otpadom, u sjeveroistocnoj Makedoniji. Primijenjeni analiticki pristup sastojao se od sljedecih koraka: (1) usporednog frakcioniranja citosolskih proteina iz jetre klena i standarda MT na osnovu njihove molekulske mase primjenom visokodjelotvorne tekucinske kromatografije s iskljucenjem po velicini (SE-HPLC), koje je bilo praceno određivanjem koncentracija odabranih metala u tako dobivenim proteinskim frakcijama pomocu spektrometra masa s induktivno spregnutom plazmom (ICP-MS) ; (2) frakcioniranja proteina prema molekulskoj masi pomocu ultrafiltera, sa svrhom odvajanja proteina molekulske mase >30 kDa, koje je bilo praceno da...
U radu je prikazano stanje ribarstva na Dojranskom jezeru, starom vodenom basenu na granici Repub... more U radu je prikazano stanje ribarstva na Dojranskom jezeru, starom vodenom basenu na granici Republike Makedonije i Grčke. Pored statističkih podataka o komercijalnom ulovu od 1946. predstavljena je i njihova komparativna analiza koja pokazuje da se sastav riblje zajednice Dojranskog jezera drastično promenio. Godišnji ulov ribe u poslednje dve dekade pokazuje trend neprekidnog opadanja što 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 statistički podaci o ulovu ribe od 1946. i upoređeni su sa podacima o nivou vode u jezeru od 1951. Uočene su brojne činjenice koje dovode u vezu količinu vode u jezeru i izlov ribe i pritom ukazuju da sadašnji nivo vode u jezeru može usloviti prekid komercijalnog ribolova. Promenjiv nivo vode u jezeru ubrzava proces eutrofikacije što se negativno odražava na kvalitet vode
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