Toksin genotipizacija sojeva Clostridium perfringens izolovanih iz hrane za životinje i njihov značaj u etiologiji enterotoksemija domaćih životinja

Clostridium perfringens is a Gram-positive, endospore-forming, anaerobic rod, ubiquitous in nature. C. perfringens strains can produce about 17 toxins. Many of them can lead to miscellaneous diseases, among which the enteric ailment may be the most common and is of utmost importance. In the present work 34 strains of C. perfringens isolated from feed and one from a cow suspected to have died of clostridial infection were subjected to molecular analysis. In order to detect the genotypes, the following genes coding for toxins were targetted: cpa, cpb, cpb2, cpe, etx and iap. The multiplex PCR assay revealed that all C. perfringens isolates from animal feed were of type A and b2-toxinogenic type A strains, possessing only the cpa (n=21), or both the cpa and the cpb2 genes (n=13). The importance of C. perfringens toxins α and β-2 in the pathogenesis of enterotoxemia is discussed and the regulation on the detection of this bacteria in animal feed questioned. The use of PCR in practise could enable the toxin-genotyping of C. perfringens isolates and, thus, provide a real basis for the establishment of maximum acceptable limits of this bacteria in feed.Clostridium perfringens je Gram-pozitivna, anaerobna, sporulišuća, štapićasta bakterija, ubikvitarno rasprostranjena u prirodi. Kod različitih sojeva C. Perfringens, do danas, identifikovano je oko 17 vrsta toksina. C. perfringens je uzročni agens različitih oboljenja (sindroma), ali su crevne infekcije/intoksikacije najčešće i od najvećeg značaja za zdravlje farmski gajenih životinja. U ovom radu prikazujemo rezultate ispitivanja sojeva C. perfringens poreklom iz hrane za životinje (n=34) i jednog izolata iz organa krave uginule sa znacima enterotoksemije na prisustvo gena: cpa, cpb, cpb2, cpe, etx i iap primenom multipleks PCR tehnike. Svi sojevi C. perfringens izolovani iz hrane za životinje, identifikovani su kao tip A koji poseduje samo cpa gen (n=21) ili tip A koji produkuje b2-toksin, odnosno ima cpa i cpb2 gene (n=13). U radu diskutujemo o ulozi alfa (α) i beta-2 (β2) toksina u patogenezi enterotoksemija domaćih životinja, kao i aktuelnom zakonskom propisu po kojem ova vrsta bakterije ne sme biti prisutna u hrani za životinje. Primena PCR tehnike u svakodnevnoj praksi omogućila bi toksin-genotipizaciju sojeva C. perfringens, a time i realne osnove za uspostavljanje graničnih dozvoljenih vrednosti za ovu vrstu bakterije u hrani za životinje

Parazitske infekcije divljih kunića i zečeva

The paper presents the most important parasitic infections of wild rabbits and hares, which harmful effect in this animal population is manifested as a gradual weakening of the immune system, reduction in fertility, weight loss and constant exhaustion. Order of Lagomorpha (hares or lagomorphs) belongs to superorder of higher mammals which includes the family of rabbits (Leporidae) which are represented in Europe as well as the family of whistleblowers (Ochotonidae) which live only in North America and Northern regions of Asia. The most important representatives of Leporidae family are European hare (Lepus europeus) and wild rabbit (Oryctolagus cuniculus). The most important endoparasitosis of hares and wild rabbits are: coccidiosis, encephalitozoonosis (nosemosis), toxoplasmosis, sarcocystosis, giardiasis, cryptosporidiosis, protostrongylosis, trichostrngylodosis, passalurosis, anoplocephalidosis, cysticercosis and fasciolosis. The most frequent ectoparasites of rabbits and wild hares are fleas, lice and ticks. Reduction in hare population, which is noticed in whole Europe including Serbia, is caused by changed living conditions, quantitatively and qualitatively insufficient nutrition, increased use of herbicides as well as various infectious diseases and the diseases of parasitic etiology. Since wild rabbits and hares pose a threat to health of domestic rabbits and people, knowledge of parasitic fauna of these wild animals is of extreme epizootiological and epidemiological importance.U radu su prikazane najznačajnije parazitske infekcije divljih kunića i zečeva, čiji se štetan uticaj kod ove populacije divljači manifestuje kao postepeno slabljenje imuniteta, smanjenje plodnosti, gubitak telesne mase i konstantna iscrpljenost organizma. Red Lagomorpha (zečevi ili dvojezupci) pripada nadredu viših sisara i obuhvata porodicu zečeva (Leporidae), koji su zastupljeni u Evropi i porodicu zečeva zviždača (Ochotonidae), koji žive samo u Severnoj Americi i severnim predelima Azije. Najznačajniji predstavnici familije Leporidae su evropski zec (Lepus europeus) i divlji kunić (Oryctolagus cuniculus). Najznačajnije endoparazitoze žečeva i divljih kunića su: kokcidioza, encefalitozoonoza (nozemoza), toksoplazmoza, sarkocistioza, đardioza, kriptosporidioza, protostrongiloza, trihostrongilidoza, pasaluroza, anoplocefalidoza, cisticerkoza i fascioloza. Najčešći ektoparaziti zečeva i divljih kunića su vaši, buve, krpelji, grinje i šugarci. Na smanjenje brojnosti populacije zečeva, koje je poslednjih godina utvrđeno u celoj Evropi i Srbiji, odgovorni su izmenjeni životni uslovi, kvalitativno i kvantitativno nezadovoljavajuća ishrana, sve veća upotreba herbicida, kao i različita oboljenja zarazne i parazitske etiologije. Pošto divlji kunići i zečevi predstavljaju rizik za zdravlje domaćih kunića i ljudi, od izuzetnog je epizootiološko/epidemiološkog značaja poznavanje parazitske faune ove vrste divljih životinja

Mastitis associated with Prototheca zopfii - an emerging health and economic problem on dairy farms

Increased incidence of protothecal mastitis has been recorded in several countries in the past ten years. The main goal of this article is to draw the attention of scientific and professional community to the emerging issue of mammary protothecosis. The article collates currently known facts about infection reservoirs, predisposing factors for the development of mastitis, clinical manifestations of the disease, and potential transmission routes within the herd as well as the measures for control and eradication. We would like to point out that identification of protothecal mastitis on a dairy farm is associated with a range of problems. Early detection of infected animals can be difficult because of predominantly subclinical course of early-stage infection, which easily spreads between cows via the milking system. Spontaneous recovery has not been recorded and infected cows typically develop chronic mastitis with granulomatous infiltration and progressive loss of functional parenchyma of the mammary gland. Substantial economic losses and health damages associated with mammary protothecosis strongly emphasise the need for developing effective prevention strategies aimed at control of the infection

Antivirus and antibacterial filters for face masks based on silver quantum dots

Available face masks, used to protect the respiratory system from various types of pathogens, show unsatisfactory efficiency because the size of viruses like severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is much smaller than the void spaces in these masks. Difficult breathing through some masks quickly tires out, which makes ordinary people avoid wearing them. These facts suggest that a new strategy is desirable for designing protective face masks. The aim of the study was to present new filters for face masks to protect people exposed to high concentrations of bacteria and viruses, particularly SARS-CoV-2. Methods. Filters for these masks were manufactured of dense cotton fabric impregnated with silver quantum dots. The filters were characterized by scanning electron microscopy and ion-coupled plasma mass spectrometry. Wettability properties were determined by measuring contact angles with water, and a color fastness test was performed. Antibacterial assay was performed using Staphylococcus (S.) aureus. Viability quantitative polymerase chain reaction (qPCR) for virus integrity assay and reverse transcription qPCR (RT-qPCR) assay were used for antiviral activity assessment. Results. In vitro assays showed extremely high efficiency of these filters in destroying S. aureus and SARS-CoV-2 virus. The filters also showed high safety and easy breathing possibilities. Conclusion. The high efficiency of these masks against SARS-CoV-2 has been demonstrated through numerous tests, and they have been approved as anti-SARS-CoV-2 masks for the first time in the world. In the meantime, this solution has been applied in practice, and the data obtained about that are very encouraging

Hypodermosis in northern Serbia (Vojvodina)

This paper describes the first documented case of cattle grub (hypodermosis) in Northern Serbia (Vojvodina). Subcutaneous warbles were determined in a six year old Simmental cow, at nine places along the spine. After the extirpation of larvae, based on the morphological characterisation, larvae of the third stage of Hypoderma bovis were diagnosed. The cow was administered therapeutic treatment, which had a favorable outcome, with no signs of recurrence. To the authors best knowledge, the case described in this paper is the first documented case of hypodermosis in cattle in Northern Serbia (Vojvodina). As the climate changed in the past few decades, it is important to pursue detailed investigations of the prevalence of this parasitic myiasis, as there are few such literature data for the Southern region of Serbia. One should also not ignore the fact that species of the genus Hypoderma can cause myiasis in humans as well

Mogućnost upotrebe rt-pcr tehnike u utvrđivanju prisustva virusa goveđe virusne dijareje u spermi priplodnih bikova

The bovine viral diarrhea (BVD) virus is a significant health-economic pathogen in cattle which can be excreted and spread also through sperm of persistently or acutely infected bulls. Native sperm of 6 bulls, found to be negative to the BVD virus by isolating the virus and using the RT-PCR method, was experimentally infected with a tenfold dilution of the non-cytopathogen 22146 strain of the BVD virus with a titer of 105,5. This way, dilutions of the BVD virus from 10-1 to 10-6 (5 x 104 TCID/50 do 0,5 TCID/50 in 0.1 ml native sperm were obtained. From sperm infected in this way, the virus was reisolated on FTB cell culture in a microtiter plate with 96 pools in which each sample of the infected sperm was set up in three samples, and each of them was titrated to a dilution of 1:2 to 1:256. The presence of the BVD virus was proven using the technique of fluorescent antibodies in a second blind passage on FTB culture cells. For cell culture an extremely toxic effect of native sperm to a dilution of 1:64 was established. The BVD virus was reisolated from sperm in all three sperm samples with 5 x 104, 5 x 103 i 5 x 102 TCID/50, and it was not reisolated from sperm with 50, with 5, and with 0.5 TCID/50 BVD virus in 0.1 ml native sperm. At the same time, the presence of the BVD viral genome was proved using the RT-PCR method in the same samples of artificially infected native sperm of bulls. A positive re suit was established in native sperm with 5 x 104, 5 x 103, 5 x 102 and 50 TCID/50 BVD virus n 0.1 ml native sperm. The experiment proved that the RT-PCR method has advantages over the isolation of the BVD virus from samples of native sperm of bulls. These are: shortterm investigations (1 to 2 days) and greater sensitivity (10 times bigger than the isolation of the virus). The isolation of the virus takes at least 10 days, and its greater sensitivity is primarily a result of the cyrotoxic effect of native sperm of bulls on cell culture.Virus goveđe virusne dijareje (BVD-a) je značajan zdravstvenoekonomski patogen kod goveda koji može da se izlučuje i širi i putem sperme trajno i akutno inficiranih bikova. Nativna sperma šest bikova, za koju je izolacijom virusa i RT-PCR metodom utvrđeno da je negativna na BVD virus, eksperimentalno je inokulisana desetostrukim razređenjima necitopatogenim 22146 sojem BVD virusa titra 105,5. Na ovaj način dobijena su razređenja BVD virusa od 10-1 do 10-6 (5 x 104 TCID/50 do 0,5 TCID/50 BVD virusa) u 0,1 ml nativne sperme. Iz ovako inokulisane sperme obavljena je reizolacija virusa na kulturi ćelija FTB u mikrotitar ploči sa 96 bazenčića, u kojoj je svaki uzorak inficirane sperme postavljen u tri primerka, a svaki od njih je titriran od razređenja 1:2 do 1:256. Prisustvo BVD virusa je dokazano tehnikom fluorescentnih antitela u drugoj slepoj pasaži na kulturi ćelija FTB. Za kulturu ćelija je utvrđen izrazito toksičan efekat nativne sperme do razređenja 1:64. Virus BVD-a je reizolovan iz sperme u sva tri primerka uzoraka sperme sa 5 x 104, 5 x 103 i 5 x 102 TCID/50, a nije reizolovan iz sperme sa 50, sa 5 i sa 0,5 TCID/50 BVD virusa u 0,1 ml nativne sperme. Istovremeno izvedeno je dokazivanje prisustva BVD virusnog genoma RT-PCR metodom u istim uzorcima virusom inokulisane nativne sperme bikova. Pozitivan rezultat je utvrđen u nativnoj spermi sa 5 x 104, 5 x 103, 5 x 102 i 50 TCID/50 BVD virusa u 0,1 ml nativne sperme. Eksperiment je ukazao da RT-PCR metoda ima prednosti u odnosu na izolaciju BVD virusa iz uzoraka nativne sperme bikova. To su: brzina ispitivanja (jedan do dva dana) i veća osetljivost (deset puta u odnosu na izolaciju virusa). Izolacija virusa traje najmanje deset dana, a njena manja osetljivost je, pre svega, rezultat citotoksičnog efekta nativne sperme bikova na kulturu ćelija

Investigations of influence of colostral antibodies on development of pathomorphological changes following experimental infection of piglets with classical swine plague virus

The pathomorphological changes established following infection with the virus of classical swine plague in non-immune individuals are well known. However, piglets present a problem from the clinical-pathological aspect, in which this virus can be multiplied in spite of established colostral antibodies, but without the exhibiting of the clinical symptoms characteristic for the disease. The question of the characteristics of the pathomorphological finding is raised in the event of the breakdown of the colostral immunity of the piglets. With the objective of determining the influence of colostral antibodies on the development of pathomorphological changes in classical swine plague, piglets aged 28, 35, 44, and 54 days, originating from sows that had received a vaccine of the K-strain of the classical swine plague virus, were experimentally infected with a virulent variety of this virus (Becker strain). The control group comprised non-vaccinated animals originating from non-vaccinated sows. Following the death and/or sacrificing of the piglets in the experiment, a pathomorphological examination was performed of all organic systems and the presence of classical swine plague virus antigens was established in organs and tissues of piglets using the immunoenzyme (ELISA) test. Even though clinical signs characteristic for this disease were not found in all animals following artificial infection, the pathomorphological findings following death and/or sacrificing indicated a successful experimental infection and was typical for the acute course of classical swine plague. Bleeding was established in most organs and serous membranes (haemorrhagic diathesis). However, certain variations were also established regarding the expression and distribution of the pathomorphological changes in certain animals

Vanadijum u ishrani živine

Vanadium (V) is essential element for poultry nutrition. Relatively low level of V ( lt 10 μg/kg of feed) is known to reduce both growth in chicks and Haugh unit value of eggs. The National Research Council (NRC) recommends the presence of very low levels of V in poultry diets, with the maximum tolerance level (MTL) being 10 mg/kg. Excessive vanadium in poultry diets has been shown to be detrimental to egg production, interior quality of eggs (albumen height), body weight and feed consumption. There is little information on the content of V in feedstuffs. Phosphates are known to be the cause of excessive V in various types of poultry diets. The objective of this study was to obtain information about the content of vanadium in phosphates and poultry feed. The samples were prepared by microwave wet digestion. Content of V was determined by the method of coupled plasma with mass spectrometry on the Agilent ICP-MS 7700. The concentrations of vanadium determined in the examined samples were above the minimum recommended levels for poultry feed, still not exceeding the maximum tolerable values.Vanadijum (V) je esencijalni element u ishrani živine. Relativno niski nivoi V ( lt 10 mg) smanjuju porast pilića i vrednosti Haugh-ovih jedinica jaja. The National Research Council (NRC) preporučuje veoma niske nivoe V u hrani za živinu, pri čemu je za maksimalni nivo tolerancije utvrđena vrednost od 10 mg/kg. Višak vanadijuma u ishrani živine ispoljava štetne efekte u proizvodnji jaja, negativno utiče na unutrašnji kvalitet jaja, telesnu masu živine i efikasnost iskorišćavanja hrane. Podaci o sadržaju V u hrani i hranivima za životinje su oskudni, ali zna se da fosfatna mineralna hraniva često sadrže visoke koncentracije ovog elementa. Cilj ovog istraživanja je bio da se dobiju informacije o sadržaju vanadijuma u hranivima i hrani za živinu. Uzorci hrane za životinje su pripremljeni mikrotalasnom digestijom, a sadržaj V je određen metodom indukovano kuplovane plazme sa masenom spektrometrijom (ICP-MS). Koncentracije vanadijuma u ispitivanim uzorcima bile su iznad minimalnih preporučenih nivoa u ishrani živine, ali nisu prelazile maksimalne tolerantne vrednosti za živinu za ovaj element

Detection of equine arteritis virus in the semen of stallions in the republic of Serbia

The results on serological testing of blood sera from stallions and mares used for breeding and the presence of the viral genome of Equine Arteritis Virus (EAV) in stallion semen are presented. The blood and semen samples were taken from a horse stable on the territory of the Republic of Serbia during 2012, 2013 and 2014. Detection of anti-EAV specific antibodies in blood sera was performed by the virus neutralization test (VNT), and identification of EAV genome RNA in stallion semen was done by reverse-transcriptase polymerase chain reaction (RT-PCR). In 2012, high seroprevalence of EAV was detected in the investigated stable. In total, 45% and 65 % of stallions and mares reacted positive, respectively, and the antibody titre values ranged between 2 and 10 log 2. High seroprevalence was confirmed in the same animals again in 2013. Out of two stallions tested semen samples in 2013, the viral genome was detected by RT-PCR in 3 examined semen samples from a seropositive stallion, while EAV was not detected in 3 semen samples of a seronegative stallion. During 2014, 11 semen samples were collected from two seropositive stallions. Again, the presence of EAV was confirmed by RT-PCR in all 8 semen samples originating from the same stallion with the EAV genome positive semen result in 2013, whereas the virus was not detected in semen samples originating from the second anti-EAV antibody positive stallion. The presence of EAV-specific antibodies was confirmed in the blood sera of the mares inseminated with the semen of seropositive stallions in 2012 and 2013

Molekularna karakterizacija nekih sojeva virusa Newcastle bolesti izolovanih u Pokrajini Vojvodini Republike Srbije

Five strains of Newcastle disease virus (NDV) were obtained from poultry in Vojvodina, Serbia during the outbreaks in 2006 and 2007. These isolates were confirmed and genotypically characterized by reverse transcription polymerase chain reaction (RT-PCR) with primer specific to the viral fusion (F) protein (572bp), and by sequencing of partial F gene for phylogenetic analysis. Phylogenetic analysis showed that all five isolated strains of Newcastle disease virus belong to genotype VII. At the same time, all five isolates were clustered in NDV subtype VIId. The examined NDV isolates express high similarity to each other (99.7-100%) and group together with the strains of Newcastle disease virus isolated previously from wild birds in Serbia during the same 2006 - 2007 outbreak. The analysis of the isolates F gene cleavage sites has shown that all five isolated strains of Newcastle disease virus had a cleavage site motif 112R-R-Q-K-R-F-117 characteristic for highly virulent, velogenic strains.Pet sojeva virusa Newcastle bolesti (NDV) je izolovano iz uzoraka suspektnog materijala poreklom od živine 2006. i 2007.godine tokom epizootije atipične kuge živine na teritoriji Vojvodine, Srbija. Ovi izolati su potvrđeni i genotipski tipizirani primenom metoda RT-PCR uz korišćenje prajmera specifičnih za deo genoma virusa koji kodira sintezu fuzionog F proteina (572bp) i sekvenciranjem dela F gena sa filogenetskom analizom. Filogenetska analiza je ukazala da je svih pet izolovanih sojeva virusa Newcastle bolesti pripadalo genotipu VII. Istovremeno, svih pet sojeva je grupisano u podtip VIId navedenog virusa. Izolovani sojevi virusa Newcastle bolesti su međusobno bili veoma slični (99,7-100%) i grupisali su se sa sojevima virusa prethodno izolovanih iz divljih ptica u Srbiji tokom izbijanja bolesti 2006. i 2007. godine. Molekularnom karakterizacijom gena na mestu deobe fuzionog F proteina ustanovljeno je da svih pet izolovanih sojeva virusa pripada visoko virulentnim velogenim sojevima