THE HYDROLOGICAL AND ENVIRONMENTAL ASPECT OF LOW FLOW ASSESSMENT IN UNGAUGED BASINS – A CASE STUDY IN THE JUŽNA MORAVA RIVER BASIN

Eighteen low flow indicators are considered in the research of sixteen hydrological stations in the Južna Morava river basin. The indicators are estimated by statistical analysis and grouped as hydrological and environmental indicators. A cross-correlation between all indicators is assessed. Environmental flows at hydrologic stations are obtained by the GEP method. The environmental low flow indicators are transferred to two small ungauged basins by regression with physiographic characteristics. The adjustment of environmental flows at ungauged basins is performed according to the locations of the donor stations in the hydrogeological regions of the studied area

Efficiency of two protocols of resynchronization of estrus and ovulation in high-producing dairy cows at peak lactation

The reproductive efficiency of the cows was monitored after two resynchronization protocols: Ovsynch (OVS) and Double Ovsynch (DOS). The research initially included 70 HF cows who entered the first synchronization protocol - Presynch. Cows that did not conceive after the first synchronization were divided into two groups and introduced to two resynchronization protocols. In the first group of cows (n=35), the DOS protocol began with the application of GnRH on day 22 after the Presynch TAI (Timed Artificial Insemination), and seven days later pregnancy check-up was done and PGF2α was applied only to non-pregnant cows (n=23), which remained in the study. In the second group of cows, the OVS protocol started on day 32 after Presynch TAI only in non-pregnant animals (n=20). Progesterone (P4) concentration was determined at the time of application of GnRH1, PGF2α and GnRH2 in both groups of cows, and then 30 days after Resynch TAI, ultrasound pregnancy diagnosis was done. A higher percentage of pregnant cows were recorded in the OVS group compared to the DOS group (45% and 35%, respectively). The concentration of P4 in the serum of cows in the DOS group during the first measurement (GnRH1) was significantly higher than the value in cows that did not conceive (p<0.05), while in the third measurement (GnRH2) the average concentration of P4 in conceiving cows was significantly lower (p<0.001) compared to cows that did not coincive. The open days period was significantly longer in pregnant cows that were resynchronized using the DOS protocol compared to cows from the OVS protocol. In conclusion, the OVS protocol of estrus resynchronization in dairy cows proved to be more successful than the DOS protocol. However, considering the advantages the OVS, it is needed to determine which day of the sexual cycle is the best to start resynchronization

Reproduktivni monitoring i praktična primena hormonskih protokola na farmi mlečnih krava

Plodnost mlečnih krava globalno opada. Ukupna efikasnost ot- krivanja estrusa kod mlečnih goveda u laktaciji je smanjena, jer je is- poljavanje znakova estrusa vrlo suptilno i često teško uočljivo od stra- ne farmera ili štalskog personala. Shodno tome, neotkrivanje estrusa, visok indeks osmenjavanja i dug servis period su glavni razlozi koji do- prinose slaboj reproduktivnoj efikasnosti. Iako je jalovost najčešći ra- zlog za isključivanje mlečnih krava iz dalje proizvodnje, procenat steo- nosti se može popraviti efikasnijim otkrivanjem estrusa, primenom hormonskih protokola koji imaju za cilj fiksno vreme osemenjavanja (engl. Timed-AI-TAI) ili fiksnim embriotransferom (engl. Timed-ET). Ovim protokolima se kontrolišu razvoj folikula i luteoliza, što kulminira sinhronom ovulacijom kod većine krava. Postoji nekoliko modifikacija za poboljšanje stope uspešne koncepcije u protokolima TAI, kao što je presinhronizacija sa 2 doze PGF2α u razmaku od 14 dana, uz za- počinjanje OvSynch protokola 12. dana posle druge aplikacije PGF2α i drugi. Programi hormonske sinhronizacije i fiksnog osemenjavanja, osiguravaju pravovremenu aplikaciju semena, uz obavezan rani ultra- zvučni pregled na steonost (30-32 dana post inseminationem) kako bi se identifikovale neplodne krave i brzo nakon toga ponovo resinhroni- zovale i/ili osemenile. Ovaj rad ima za cilj da prikaže značaj pravilnog vođenja reproduktivne evidencije, da definiše najznačajnije reproduk- tivne parametre i objasni njihovu praktičnu primenu u izračunavanju realnih troškova farme. Takođe, u njemu se objašnjava kako se ultra- zvučnim pregledom plotkinja i utvrđivanjem njihovog trenutnog repro- duktivnog statusa definišu adekvatni hormonski protokoli u cilju sin- hronizacije estrusa i ovulacije

Improving the combined boiler-stove MBS 90kv construction

Razvijena je unapređena konstrukcija originalnog kombinovanog štednjaka kotla MBS 90KV. Konstrukcija je unapređena da bi se zadovoljili zahtevi evropskog propisa o ovoj vrsti proizvoda EN 12815, koji je stupio na snagu marta 2002. godine. Na ranije projektovanoj i izvedenoj ispitnoj instalaciji obavljena su ispitivanja nazivne toplotne snage, vremena postizanja stacionarnog stanja i stepena korisnosti pri pogonu na tri različita goriva ogrevno drvo, ugalj i briket od ostatka prerade drveta. U radu je izložen deo rezultata dobijenih ovim ispitivanjima.The improved construction of original combined stove- -boiler MBS 90 KV has been developed. The construction is improved in order to live up requests of the European regulation of this kind of products EN 12815, which has went into effect in March 2002. On already designed and performed test installation, the tests of thermal power, time of reaching the steady state and the design of performance during driving by three different fuels: wood coal and briquette from the wood treatment, have been carried out. The paper deals with a part of the results obtained by this testing

Improving the combined boiler-stove MBS 90kv construction

Razvijena je unapređena konstrukcija originalnog kombinovanog štednjaka kotla MBS 90KV. Konstrukcija je unapređena da bi se zadovoljili zahtevi evropskog propisa o ovoj vrsti proizvoda EN 12815, koji je stupio na snagu marta 2002. godine. Na ranije projektovanoj i izvedenoj ispitnoj instalaciji obavljena su ispitivanja nazivne toplotne snage, vremena postizanja stacionarnog stanja i stepena korisnosti pri pogonu na tri različita goriva ogrevno drvo, ugalj i briket od ostatka prerade drveta. U radu je izložen deo rezultata dobijenih ovim ispitivanjima.The improved construction of original combined stove- -boiler MBS 90 KV has been developed. The construction is improved in order to live up requests of the European regulation of this kind of products EN 12815, which has went into effect in March 2002. On already designed and performed test installation, the tests of thermal power, time of reaching the steady state and the design of performance during driving by three different fuels: wood coal and briquette from the wood treatment, have been carried out. The paper deals with a part of the results obtained by this testing

Variations of total electron content over Serbia during the increased solar activity period in 2013 and 2014

To understand general ionosphere properties over Serbia, an analysis of temporal and spatial ionosphere Total Electron Content (TEC) over the region was performed. The present research focuses on daily, seasonal and spatial ionosphere variations, based on TEC series calculated from the GNSS ie. GPS measurements. This analysis provides for characterization of ionosphere nature and fine structure over Serbia, both locally and regionally. For the days with high solar activity changes of TEC values ranges from minimum 4 Total Electron Content Units (TECU), in night hours, up to 55 TECU around the noon. It is shown that that changes are equivalent to the to the delay of GPS signals approximately 8.8 m in in vertical direction during the (maximum) daily conditions and the delay of 0.6 m during the (minimum) night conditions. Also, it is shows that a seasonal TEC differences follows directly Son activity during the seasons, and maximal differences of TEC values between the seasons reaching values of 45 TECU, again in the years of high Son's activities. For spatial changes all gained results indicate that there exist changes in all directions which cannot be recognized as constant bias or a trend

Hematological, biochemical, and acid-base response of trotters to submaximal exercise at the end of the horse racing season

Depending on intensity, physical exercise in horses causes various changes in the parameters of hematological, biochemical, acid-base, and electrolyte status, which can affect the health and athletic performance of the horse. This study’s objective was to look at how submaximal exercise at the end of the racing season affected the horses’ hematological, biochemical, acid-base, and electrolyte status markers. In this study, eight (n=8) trotters, aged 4±2 years, were involved. Venous blood samples were drawn from each horse by jugular puncture before and after exercise to determine hematologic, biochemical, acid-base and electrolyte parameters. The submaximal physical exercise in this study was two intervals of 2,000 m of slow trotting and two consecutive runs of 500 m at submaximal level. Hematocrit (HCT), red blood cell (RBC) and monocyte count, hemoglobin (HGB) concentration, aspartate aminotransferase (AST) activity, and glucose concentration increased significantly after the exercise. Additionally, significant decreases in venous blood pH, bicarbonate (HCO3 - ) and total CO2 (TCO2) concentration, base excess of the extracellular fluid (BEecf), and ionized Ca2+ (iCa2+) concentrations were established after exercise. In contrast, partial pressure of CO2 (pCO2), total concentration of weak acids (Atot), the anion gap (AG), and total protein and lactate concentrations were significantly higher after exercise. Considering the significant changes in the parameters of hematological, biochemical, and acid-base status after submaximal exercise, determining those parameters would be useful for monitoring the health and performance of trotters

Genome-wide analysis of milk production traits and selection signatures in Serbian Holstein-Friesian Cattle

To improve the genomic evaluation of milk-related traits in Holstein-Friesian (HF) cattle it is essential to identify the associated candidate genes. Novel SNP-based analyses, such as the genetic mapping of inherited diseases, GWAS, and genomic selection, have led to a new era of research. The aim of this study was to analyze the association of each individual SNP in Serbian HF cattle with milk production traits and inbreeding levels. The SNP 60 K chip Axiom Bovine BovMDv3 was deployed for the genotyping of 334 HF cows. The obtained genomic results, together with the collected phenotypic data, were used for a GWAS. Moreover, the identification of ROH segments was performed and served for inbreeding coefficient evaluation and ROH island detection. Using a GWAS, a polymorphism, rs110619097 (located in the intron of the CTNNA3 gene), was detected to be significantly (p < 0.01) associated with the milk protein concentration in the first lactation (adjusted to 305 days). The average genomic inbreeding value (FROH) was 0.079. ROH islands were discovered in proximity to genes associated with milk production traits and genomic regions under selection pressure for other economically important traits of dairy cattle. The findings of this pilot study provide useful information for a better understanding of the genetic architecture of milk production traits in Serbian HF dairy cows and can be used to improve lactation performances in Serbian HF cattle breeding programs

Salmonella in wild boars (Sus scrofa): Characterization and epidemiology

The large study on Salmonella spp. in the population of wild boars from twelve hunting estates in the South-West Vojvodina, Serbia was conducted with the aim to investigate the prevalence of Salmonella spp. in wild boars and to trace Salmonella sources. The hunting estates had similar epidemiological characteristics, i.e. lowland regions with an intensive management system of wild boars. The prevalence of Salmonella in wild boars was determined and the examination of molecular similarities of strains isolated from wild boars and domestic animals (pigs and poultry from nearby farms) was performed. The total number of 425 wild boars (25.3% of total population), shot on official hunts, were sampled (425 feces and 425 mesenteric lymph nodes samples) and examined by standard ISO protocols. Subtyping of the isolates was performed and compared by Pulsed-field gel electrophoresis (PFGE). The Salmonella prevalence in the fecal samples was 3.1% and in the lymph nodes was 0.2%. Salmonella Enteritidis was the most dominant serotype. A high molecular similarity was found between Salmonella isolates from wild boars and domestic animals. The proximity of communities and domestic animals, as well as improper removal of animal waste were identified as important epidemiological factors which significantly affect the epidemiology of Salmonella in wild boars from lowlands

Normalne vrednosti osnovnih fizioloških parametara kod balkanskog magarca na Staroj planini

Balkanski magarac je autohtona primitivna rasa koja se uzgaja u brdsko-planinskim krajevima Srbije i Crne gore. Predstavlja važan resurs u pogledu očuvanja genotipa u našoj zemlji. Danas se najveći broj balkanskih magaraca nalazi u Specijalnom rezervatu prirode “Zasavica”, nacionalnom parku “Stara planina” i u selu Kovilj, nedaleko od Novog Sada. Uglavnom se koriste za proizvodnju mleka i kao turistička atrakcija na farmi. Podaci u literaturi, koji se odnose na poznavanje vrednosti osnovnih fizioloških parametara kod magaraca, su do skoro bili oskudni. To je dovelo do razvoja velikog broja studija, posebno na magarcima sa Stare planine, čiji je krajnji rezultat bio definisanje osnovnih fizioloških vrednosti parametara trijasa, hematoloških i biohemjiskih vrednosti parametara krvi. Poznavanje vrednosti ovih parametara je od velike važnosti veterinarima za pravilnu interpretaciju kliničkih nalaza i dijagnostiku oboljenja kod magaraca.Zbornik predavanj