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U okviru parazitologije poslednjih decenija u Srbiji gotovo isključivo su se izučavale infekcije prouzrokovane endoparazitima krvi, digestivnog i respiratornog sistema, kao i artropode – ektoparaziti kože ili pak vektori oboljenja različite etiologije. U skladu sa time, favorizovane su koprološke, hematološke i dermatološke metode dijagnostike. Urološkim metodama nije se pridavao poseban značaj, jer se polazilo od pretpostavke da na ovom području ne postoje preduslovi za infekciju domaćih životinja parazitima urinarnog sistema. Globalno zagrevanje, povećanje prosečne temperature i obilne padavine, kao i povećana mobilnost ljudi i životinja uslovili su stvaranje povoljnih uslova za pojavu, održavanje i širenje infekcija koje ranije nisu bile prisutne. Izvesna parazitološka ispitivanja divljih životinja rezultirala su prvim nalazom nematode Capillaria plica 2019. godine kod crvenih lisica sa područja Kolubarskog okruga. Kasnije je utvrđeno prisustvo i potvrđena dijagnoza urinarne kapilarioze kod lovačkih pasa u različitim delovima Srbije. Ovaj nalaz podstakao je produžetak istraživanja mogućeg prisustva drugih nematoda urinarnog sistema divljih i domaćih mesojeda. Jedna od njih je i vrsta Dioctophyma renale, koja poseduje visok zoonozni potencijal. Zbog rizika koje D. renale može imati po zdravlje vlasnika inficiranih pasa i mogućnosti da njeno prisustvo ne bude zapaženo, potrebno je doktorima veterinarske medicine u maloj praksi i na terenu sugerisati da u diferencijalnoj dijagnostici parazitskih infekcija i oboljenja urinarnog trakta mesojeda obrate pažnju i na ove helmintoze.

Dogs are the most popular pets worldwide. Close contact between dogs and people increases the risk of transmission of various zoonotic parasitic infections. Given the importance of veterinary medicine in preserving the One Health concept, the aim of this research was to identify intestinal parasites that may have zoonotic potential and to evaluate risk factors (individual and environmental). The research was conducted in Serbia in 2022 and 2023 on 382 owned dogs, using qualitative methods of coprological examination with a concentration on parasitic elements. The overall prevalence of intestinal parasites was 62.6%, with the following detected: protozoa: Cystoisospora spp. (9.2%), Sarcocystis spp. (4.5%), Neospora caninum/Hammondia spp. (3.7%), Giardia intestinalis (11.8%); nematoda: Toxocara canis (11.5%), Toxascaris leonina (4.2%), family Ancylostomatidae (38.0%), Trichuris vulpis (21.5%), Capillaria spp. (10.5%); trematoda: Alaria alata (1.6%) and cestodes from the Taeniidae family (1.3%). Factors like age, size and coat length, as well as the way of living, attitude and diet were linked to a significantly higher (p < 0.05) prevalence of intestinal parasites. Based on the results of coprological diagnostics, this research indicates the importance of educating dog owners, conducting routine parasitological tests on their pets and regular deworming strategies.

Nosema ceranae, a microsporidian parasite, as one of the stressors that contribute to honey bee decline, has a significant negative impact on the longevity, productivity, and reproductive capacity of honey bee colonies. There are several different strategies for Nosema infection control, including natural-based and antibiotic-based products. In this study, we tested wormwood and oak bark-based supplement “Medenko forte” on survival, Nosema infection, oxidative stress, and expression of immune-related genes in artificially N. ceranae-infected bees. The results revealed a positive influence on the survival of Nosema-infected bees, irrespectively of the moment of supplement application (day 1, day 3, or day 6 after bee emergence), as well as reduction of Nosema loads and, consequently, Nosema-induced oxidative stress. Supplementation had no negative effects on bee immunity, but better anti-Nosema than immune-stimulating effects were affirmed based on expression levels of abaecin, defensin, hymenoptaecin, apidaecin, and vitellogenin genes. In conclusion, the tested supplement „Medenko forte” has great potential in the health protection of Nosema-infected bees. However, further investigations need to be performed to elucidate its mechanisms of action.

Dioctophimosis is an endoparasitism in dogs caused by Dioctophyma renale, a nematode with an indirect life cycle and high zoonotic potential. Infection in dogs occurs through ingestion of transitional/paratenic hosts containing infective larvae. Th e preferred site of parasitism is the right kidney, although the parasite may also be ectopically localized in subcutaneous tissue, internal organs, peritoneum, and mediastinum. Since dogs are usually infected with a small number of parasites, the disease is asymptomatic, making the diagnosis of this disease in clinical veterinary practice rather diffi cult. In addition, as dogs are usually infected with a small number of parasites, the disease is asymptomatic, which makes the diagnosing of this disease in clinical veterinary practice diffi cult. Th e long prepatent period, lasting three to fi ve months, makes it impossible to diagnose the disease in dogs younger than six months. Clinical suspicion of dioctophimosis in dogs is established on the basis of anamnestic/epizootiologic data and the clinical picture, while the fi nal diagnosis is made ante mortem or post mortem on the basis of reliable diagnostic parameters and methods. Th e most practical application in routine diagnosis of canine dioctophimosis is the detection of D. renale eggs in urine sediment. When dioctophimosis is suspected in carnivores, the diff erential diagnosis should exclude urinary capillariosis, feline polycystic nephropathy, leptospirosis, renal fi brosis, and nephritis of various etiology. Th e outcome of treatment is uncertain and includes surgical removal of the aff ected kidney or drug therapy with avermectin derivatives. Prophylaxis consists of preventing contact of dogs with potential transitional hosts and controlling the feeding of their heat-untreated meat. Because of the potential risks that D. renale may have on the health of dog owners, education on the etiopathogenesis and means of occurrence, maintenance, and spread of this nematod, Dioktofi moza je endoparazitoza pasa koju prouzrokuje Dioctophyma renale, nematoda sa indirektnim životnim ciklusom i visokim zoonoznim potencijalom. Infekcija pasa nastaje ingestijom prelaznih/paratenih domaćina koji u sebi sadrže infektivne larve. Predilekciono mesto parazitiranja je desni bubreg, uz mogućnost ektopične lokalizacije parazita u supkutanom tkivu, unutrašnjim organima, peritoneumu i medijastinumu. Pošto su psi uglavnom infi cirani malim brojem parazita, oboljenje protiče asimptomatski, što u kliničkoj veterinarskoj praksi otežava dijagnostiku ovog oboljenja. Dug prepatentni period, koji traje od tri do pet meseci, onemogućava dijagnostiku oboljenja kod pasa mlađih od šest meseci. Klinička sumnja na dioktofi mozu kod pasa postavlja se na osnovu anamnestičkih/ epizootioloških podataka i kliničke slike, dok se precizna dijagnoza utvrđuje ante mortem ili post mortem na osnovu pouzdanih dijagnostičkih parametara i metoda. Najveću praktičnu primenu u rutinskoj dijagnostici dioktofi moze pasa ima nalaz jaja D. renale u sedimentu urina. Kod sumnje na dioktofimozu mesojeda diferencijalno dijagnostički treba isključiti urinarnu kapilariozu, policističnu nefropatiju mačaka, leptospirozu, fi brozu bubrega i nefritise različite etiologije. Lečenje je neizvesno i podrazumeva hirurško uklanjanje promenjenog bubrega ili medikamentoznu terapiju derivatima avermektina. Profi laksa je zasnovana na sprečavanju kontakta pasa sa potencijalnim prelaznim domaćinima i kontrolisanje ishrane njihovim termički neobrađenim mesom. Zbog potencijalnih rizika koje D. renale može imati po zdravlje vlasnika pasa, neophodna je edukacija o etiopatogenezi i mogućnostima pojave, održavanja i širenja ove nematode.

Since dogs and humans share their living environments and effectuatevery close contactswith each others, with dog owners not caring adequately for their pets, there is a possibility of transmission of particular parasitic diseases from dogs to humans. In view of the fact that dogs are carriers and definitive hosts of a large number ofzoonotic endoparasites, their feces may represent a source of infection for humans and a real threat to their health. That is the reason for raising the level of awareness among citizens about the necessity of executing zoohygienic measures in dog breeding, as well as about the significance of causally planned dehelminthization and anti-ectoparasitic treatments. It is essential as well that dog owners perform regular coprological examinations, immediately after getting the dog and four times a year afterwards, abiding by the principle of shifting the preparations used based on their different chemical formulations. A timely diagnosis of intestinal parasites in dogs and proper treatment of infected animals enable the prevention of these infections in humans. Contamination of public areas with intestinal parasites from dog feces represents a public health problem that should be kept under control using the appropriate social medicine approach. Such an approach would typically involve health education measures related to the control of parasite transmission in the environment, the presentation to dog owners of the guidelines for the prevention of the occurrence, persistence, and spread of zoonotic diseases, and health education of medical and veterinary professionals, pet owners, and the wider community regarding the preservation of the health of both humans and pet animals. An increased level of knowledge and corrected attitudes and behaviors among individuals would certainly contribute to more effective prevention of zoonotic diseases.

One of the most important approaches in the prevention and treatment of nosemosis is the use of herbal preparations as food supplements for bees. Therefore, the aim of this study was to investigate the effects of a plant-based supplement branded as “B+” on honeybees in a laboratory experiment. Four experimental groups were established: treated group (T), N. ceranae-infected and treated group (IT), N. ceranae-infected group (I) and non-infected group (NI). Survival, N. ceranae spore load and oxidative stress parameters together with expression levels of antioxidant enzyme genes and vitellogenin gene were monitored. The mortality in the T, IT and NI groups was significantly (p < 0.001) lower than in than in the I group. Within Nosema-infected groups, the IT group had a significantly lower (p < 0.001) number of N. ceranae spores than the I group. In addition, expression levels of genes for antioxidant enzymes were lower (p < 0.001) in the IT group compared to the I group. The concentration of malondialdehyde and the activities of antioxidant enzymes (superoxide dismutase, catalase and glutathione S-transferase) were significantly lower (p < 0.001) in the IT group compared to the I group. No negative effects of the tested supplement were observed. All these findings indicate that the tested supplement exerted beneficial effects manifested in better bee survival, reduced N. ceranae spore number and reduced oxidative stress of bees (lower expression of genes for antioxidant enzymes and oxidative stress parameters).

Prirodna jedinjenja, koja imaju brojna farmakodinamska dejstva, mogu biti ključ za rešenje problema rezistencije parazita na antiparazitske lekove, koja je sve češće prisutna i opisivana u stručnoj i naučnoj literaturi. Poslednjih decenija postoji veliko interesovanje za ispitivanje farmakodinamskih i hemijskih karakteristika pčelinjih proizvoda koji su izvor prirodnih bioaktivnih supstanci. Dokazano je da ovi proizvodi mogu ispoljiti raznolike pozititivne efekte u organizmu ljudi i životinja. Pčelinji proizvodi ‐ propolis, apitoksin, polen i med ‐ mogu imati i izvesno antiparazitsko dejstvo protiv određenih vrsta protozoa i helminata. Lekovita svojstva navedenih proizvoda uslovljena su prisustvom i koncentracijom određenih hemijskih supstanci, koji se razlikuju u zavisnosti od geografskog porekla i florističkog sastava u određenom regionu, na šta ukazuju regionalne varijacije u njihovom antiparazitskom delovanju. Pretpostavlja se da postoji nekoliko mogućih mehanizama kojim pčelinji proizvodi deluju protiv infekcija prouzrokovanih parazitima. To su: aktiviranje makrofaga koji ubijaju parazite stvaranjem reaktivnih kiseoničnih i azotnih vrsta (propolis, polen); inhibicija angiogeneze u inficiranom tkivu (propolis); različiti imunomodulatorni efekti; indukovanje mehanizama apoptoze u ćelijama parazita (propolis, med); sprečavanje prodiranja parazita u ćeliju domaćina formiranjem fizičke barijere ili inhibiranjem proteina i enzima neophodnih za invaziju parazita (propolis); narušavanje integriteta membrana i organela ćelija parazita (propolis). Ključnu ulogu u ostvarivanju ovih efekata igraju flavonoidi i fenolna jedinjenja sadržana u propolisu, polenu, medu i apitoksinu. Istraživanja izvedena većinom in vitro i na eksperimentalnim životinjama dokazala su antiparazitsku efikasnost pojedinih pčelinjih proizvoda. Ukoliko se ovaj potencijal potvrdi daljim ispitivanjima, može se očekivati da će se bioaktivne komponente izolovane iz pčelinj

In this preliminary study, we applied the Multivariate Curve Resolution- Alternating Least Squares (MCR-ALS) method to analyze the excitation-emission matrices of multifloral honey samples, combined with differential scanning calorimetry (DSC) to estimate infection of honey bee colonies with N. ceranae or V. destructor. Fluorescence spectroscopy combined with MCR-ALS was used to determine the ratio of the spectral components originating from proteins (C1) and phenolics (C2), two minor but essential constituents of honey, as a ratiometric indicator of infection level in related hives. The C1/C2 ratio decreased linearly with the increase of infection in both N. ceranae and V. destructor cases, the R2 was 0.941 and 0.912, respectively. Additionally, DSC has shown that the magnitude of changes in sugar environments of the honey samples, reflected in sugar phase transitions, rises with increasing infection level in bee colonies. These results indicate that fluorescence combined with MCR-ALS could be used for rapid, non-destructive and cheap screening of honey to estimate the level of infection of honey bee colonies.

donosne pčele (Apis mellifera). Izaziva bolest nozemozu (nozematozu) i u zavisnosti od stepena infekcije i jačine pčelinjih društava, ostavlja značajne posledice na zdravlje, reproduktivne i produktivne sposobnosti pčela. Antibiotik fumagilin je godinama bio jedini lek dostupan za kontrolu ovog patogena. Njegova primena dovedena je u pitanje zbog nedostataka koji prate njegovu primenu (efikasnost, mortalitet pčela i pojava rezidua u pčelinjim proizvodima). Širom sveta se sprovode istraživanja sa ciljem pronalaska alternative za kontrolu nozeme. U ovom radu prikazani su naši rezultati ispitivanja dijetetskih suplemenata na bazi prirodnih/biljnih ekstrakata (Medenko forte i ekstrakti gljiva Agaricus blazei i A. bisporus), timola i vitaminsko-mineralnog aditiva (BEEWELL AminoPlus). Kod pčela tretiranih svim nabrojanim suplementima i fumagilinom kao kontrolnim tretmanom, praćen je broj spora N. ceranae, nivoi ekspresije gena značajnih za imunitet pčela kao i parametri oksidativnog stresa. Svi preparati primenjivani su preventivno (tri dana pre infekcije), u trenutku inficiranja, kao i tri dana nakon infekcije sa N. ceranae, u cilju određivanja najboljeg momenta za primenu. Dokazani su negativni efekti fumagilina kada je preventivno primenjivan kod neinficiranih pčela. Kod inficiranih pčela većina testiranih suplemenata dovela je do smanjenja broja spora N. ceranae, a pokazali su i zaštitni efekat u smislu sprečavanja imunosupresije i oksidativnog stresa., The microsporidian Nosema ceranae is an obligate intestinal parasite of the honey bee (Apis mellifera). It causes nosemosis and, depending on the infection level and the strength of the infected bee colonies, causes significant health disorders, including malfunction of reproductive and productive capabilities of bees. The antibiotic fumagillin was the only drug available for Nosema control for many years. However, use of fumagillin has been questioned due to the drawbacks related to its efficacy, bee mortality and the presence of residues in bee products. Studies aimed to find alternatives for Nosema control are being conducted worldwide. In this paper, our results related to diet supplements based on natural/plant extracts (Medenko forte and extracts of Agaricus blazei and A. bisporus), thymol and vitamin-mineral additive (BEEWELL AminoPlus) are presented. Bees were treated with these supplements and fumagillin (control treatment) and gene expression levels (important for bee immunity), as well as oxidative stress parameters were assessed. In order to determine adequate time for application, all supplements were applied preventively (three days before infection), at the time of infection, as well as three days after N. ceranae infection. In uninfected bees, fumagillin demonstrated adverse effects when applied prophylactically. In Nosema-infected bees, tested supplements mainly contributed to the decrease of N. ceranae spore levels, but also exhibited a protective effect based on level of immune-related gene expression and parameters of oxidative stress.

This paper studies the presence of developmental forms of gastrointestinal parasites in soil and sand samples, as well as in dog feces collected from public green spaces in Belgrade. The paper incorporates the spread analysis of contamination over different segments of parks. Four public green spaces in Belgrade were chosen, all containing an open-spaced children’s playground and a fenced dog park. Sample analysis of soil/sand was examined using qualitative methods without concentration (native slide) and with concentration (passive sedimentation and gravitational centrifugal flotation). In total, 106 samples have been collected out of which 60 samples of soil, 36 of dog faeces and ten samples of sand. Seven different agents have been detected, out of which five nematodes - Ancylostoma/Uncinaria spp., Trichuris spp., Capillaria spp., Toxocara spp., Toxascaris leonina and two protozoa - Isospora spp. and Giardia intestinalis. The overall prevalence of contamination of soil samples was 31.67% and a statistically significant difference in the prevalence of ancylostoma eggs was found between different locations. The most common agent detected in the dog’s faeces was Isospora spp., with a prevalence of 5.56%, followed by Giardia intestinalis and ancylostomatids with a prevalence of 2.78% each. The sand samples had no parasitic elements found. The contamination by parasites and by dogs’ faeces was equally dispersed in all segments of the examined locations.There is a great need to raise public awareness on the issue, and by the joint action of veterinarians, medical doctors, pet owners and people using public parks for recreation - a precondition is created for the sustainability of the “One Health” concept which implies the preservation of the environment and human and animal health.

With an almost global distribution, Varroa destuctor is the leading cause of weakening and loss of honey bee colonies. New substances are constantly being tested in order to find those that will exhibit high anti-Varroa efficacy at low doses/concentrations, without unwanted effects on bees. Lithium (Li) salts stood out as candidates based on previous research. The aims of this study were to evaluate Li citrate hydrate (Li-cit) for its contact efficacy against Varroa, but also the effect of Li-cit on honey bees by estimating loads of honey bee viruses, expression levels of immune-related genes and genes for antioxidative enzymes and oxidative stress parameters on two sampling occasions, before the treatment and after the treatment. Our experiment was performed on four groups, each consisting of seven colonies. Two groups were treated with the test compound, one receiving 5 mM and the other 10 mM of Li-cit; the third received oxalic acid treatment (OA group) and served as positive control, and the fourth was negative control (C group), treated with 50% w/v pure sucrose-water syrup. Single trickling treatment was applied in all groups. Both tested concentrations of Li-cit, 5 and 10 mM, expressed high varroacidal efficacy, 96.85% and 96.80%, respectively. Load of Chronic Bee Paralysis Virus significantly decreased (p < 0.01) after the treatment in group treated with 5 mM of Li-cit. In OA group, loads of Acute Bee Paralysis Virus and Deformed Wing Virus significantly (p < 0.05) increased, and in C group, loads of all viruses significantly (p < 0.01 or p < 0.001) increased. Transcript levels of genes for abaecin, apidaecin, defensin and vitellogenin were significantly higher (p < 0.05—p < 0.001), while all oxidative stress parameters were significantly lower (p < 0.05—p < 0.001) after the treatment in both groups treated with Li-cit. All presented results along with easy application indicate benefits of topical Li-cit treatment and complete the mosaic of evidence on the a

In this preliminary study, we applied the Multivariate Curve Resolution- Alternating Least Squares (MCR-ALS) method to analyze the excitation-emission matrices of multifloral honey samples, combined with differential scanning calorimetry (DSC) to estimate infection of honey bee colonies with N. ceranae or V. destructor. Fluorescence spectroscopy combined with MCR-ALS was used to determine the ratio of the spectral components originating from proteins (C1) and phenolics (C2), two minor but essential constituents of honey, as a ratiometric indicator of infection level in related hives. The C1/C2 ratio decreased linearly with the increase of infection in both N. ceranae and V. destructor cases, the R (2) was 0.941 and 0.912, respectively. Additionally, DSC has shown that the magnitude of changes in sugar environments of the honey samples, reflected in sugar phase transitions, rises with increasing infection level in bee colonies. These results indicate that fluorescence combined with MCR-ALS could be used for rapid, non-destructive and cheap screening of honey to estimate the level of infection of honey bee colonies.

In this preliminary study, we applied the Multivariate Curve Resolution- Alternating Least Squares (MCR-ALS) method to analyze the excitation-emission matrices of multifloral honey samples, combined with differential scanning calorimetry (DSC) to estimate infection of honey bee colonies with N. ceranae or V. destructor. Fluorescence spectroscopy combined with MCR-ALS was used to determine the ratio of the spectral components originating from proteins (C1) and phenolics (C2), two minor but essential constituents of honey, as a ratiometric indicator of infection level in related hives. The C1/C2 ratio decreased linearly with the increase of infection in both N. ceranae and V. destructor cases, the R2 was 0.941 and 0.912, respectively. Additionally, DSC has shown that the magnitude of changes in sugar environments of the honey samples, reflected in sugar phase transitions, rises with increasing infection level in bee colonies. These results indicate that fluorescence combined with MCR-ALS could be used for rapid, non-destructive and cheap screening of honey to estimate the level of infection of honey bee colonies.

Native goat breeds in Serbia has been recognized as an important element of regional agrobiodiversity and play an important role in the safeguarding of cultural and traditional heritage. The aim of this study was to identify the main welfare issues likely to be encountered in extensive goat farming systems with an emphasis on parasitological infections. The study was conducted during the winter season on four small farms of native Balkan and Serbian white goats. For welfare assessment, animal-based indicators from AWIN protocol for goats were used. All fecal samples for parasites were qualitatively and quantitatively examined. The main welfare issues identified were poor hair coat condition (62.79%), dirty and light soiling hindquarters (31.40%), thin body condition score (26.74%), abscesses (19.78%), and udder asymmetry (18.60%). In addition, an important and prevalent welfare problem identified across all farms was parasite infection and weak significant (p < 0.001) correlation between certain parasites (Strongylidae, Moniezia spp., Buxtonella sulcate, and Protostrongylidae) and welfare indicators such as poor hair coat condition and nasal discharge. The results of this study provided the first overview and valuable insight into the impact of extensive systems on the welfare of native goats in the Balcan region.

Colony losses, including those induced by the colony collapse disorder, are an urgent problem of contemporary apiculture which has been capturing the attention of both apiculturists and the research community. CCD is characterized by the absence of adult dead bees in the hive in which few workers and a queen remain, the ratio between the brood quantity and the number of workers is heavily disturbed in favor of the former, and more than enough food is present. Robbing behavior and pests usually attacking the weakened colony do not occur. In the present paper, the causes of the emergence of this problem are discussed, as well as the measures of its prevention. The following factors, which lead to colony losses, are analyzed: shortage of high-quality food (pollen and honey); infestation with parasites, primarily with Varroa destructor, and mixed virus infections; bacterial infections (American and European foulbrood), fungal infections (nosemosis and ascosphaerosis) and trypanosomal infections (lotmariosis); and, finally, general management of the apiary. Certain preventive measures are proposed: (1) providing ample high-quality forage and clean water, (2) avoiding sugarisation, i.e. superfluous use of sugar syrup, (3) meeting the nutritional needs of the colony, (4) when feeding bees, taking care of the timing and the composition of diet, avoiding pure sugar syrup which in excessive quantities may induce energetic and oxidative stress, (5) when there is a shortage of natural feed - honey in the brood chamber - use sugar syrup with natural/artificial supplements to avoid protein starvation, (6) organized control of V. destructor in the colonies is obligatory due to its vector role, and (7) compliance with hygienic and sanitary measures and principles of good apiculture practice and management in apiaries. To conclude, all preventive measures are feasible in compliance with rules and regulations concerning regular spring and autumn bee health monitoring by licensed vete

A recently described trypanosomatid species Lotmaria passim and the microsporidium Nosema ceranae infect the honey bee (Apis mellifera), but the interspecific dynamic of these two common gut parasites is unknown. In this study, a real-time qPCR assay was developed to enable the specific detection and quantification of L. passim. The annual dynamics of N. ceranae and L. passim infections were evaluated in ten A. mellifera colonies naturally infected with both parasites at one apiary in Serbia from March 2016 to March 2017. Ten samples (60 bees abdomens) were taken from each colony on 8 sampling occasions. L. passim infection level was evaluated with qPCR, while N. ceranae infection was measured by spore counts. N. ceranae infection level was significantly higher in comparison with that of L. passim (spore or cell equivalents/bee, respectively). Significant positive correlation between infection levels of the parasite species indicates their similar annual dynamics, whilst the differences in the levels of infection between particular months point to a seasonal pattern in the incidence of both parasites. The assay which has been developed and validated creates opportunity for detailed study of L. passim infection kinetics and the improvement in the management practices in beekeeping related to these two parasites.

The present study was designed to examine the harmful effects of low level ochratoxin A (OTA) for different period and different dietary OTA levels for same period of ingestion as well as to assess the resting period necessary to revoke any adverse effects of OTA. The trial was performed on 72 day-old chickens with 12 broilers in each group. The experimental groups were offered feed contaminated with 0.5 ppm OA during 7, 14 or 21 days in the first evaluation, and feed contaminated with 0.5, 1.0 or 1.5 ppm OTA for 7 days in the second evaluation. The control group (K) received feed free of toxin. Broilers in the control groups had an average daily gain of 43.5 g and a feed: gain ratio of 1.97 kg. OTA expressed a negative effect on performance proportion to the time of exposure and to the amount of dietary toxin showing prolong and cumulative effects. Early detection of OTA and exclusion of contaminated feed could partially prevent its adverse effects, but not less than three weeks of recovery is needed to nullify the damage., Cilj rada je bio da se utvrde količine OTA u hrani koje izazivaju neželjene efekte sa aspekta doze i dužine ekspozicije, kao i da se utvrdi vreme odmora nakon zamene kontaminirane hrane potrebno za povlačenje tih efekata. U prvom ogledu su brojleri nakon dve nedelje pripreme dobijali 0,5 ppm OTA tokom 7 14 ili 21 dan. U drugom ogledu brojleri su dobijali 0,5, 1,0 ili 1,5 ppm OTA tokom 7 dana. Kontrolna grupa (K) je dobijala hranu bez toksina. Brojleri kontrolne grupe su postigli dnevni prirast od 43.5 g uz konverziju hrane od 1.97 kg. Ohratoksin je ispoljio negativne efekte na proizvodne rezultate proporcionalno dužini unošenja i količini u hrani, ispoljavajući protrahirano i kumulativno dejstvo. Rana detekcija prisustva OTA u hrani i isključivanje kontaminirane hrane može delimično da prevenira štetne efekte, ali je neophodan odmor od bar tri nedelje da se oni ublaže.