Effects of individual versus group housing system during the weaning-to-estrus interval on reproductive performance of sows.

Selection of appropriate housing conditions for sows is critical for their physical health and long-term reproductive success. The present objective was to evaluate the influences of housing system postweaning (i.e., individual stalls (IS) or group pens (GP)), season and parity on piglet productivity of sows in a commercial setting. This study utilized 3 053 Polish Large White×Polish Landrace sows that were weaned at a rate of 20-30 animals per week at the median age of 4 weeks; 1 474 sows were moved into GP of seven to eight animals each, while 1 579 were placed in IS after weaning. Starting 2 days postweaning all animals were checked for estrus with a teaser boar and then artificially inseminated using 3×109 spermatozoa per dose of an inseminate at the onset of heat and 24 h later. The proportion of sows showing the signs of standing heat at or before 6 days postweaning was greater (P < 0.05) for sows moved to GP compared with IS; this difference manifested mainly in second parity sows weaned in the summer and fall. Conception and farrowing rates were significantly higher (P < 0.01) and the weaning-to-estrus interval shorter in GP compared with IS sows in every season but autumn. Mean litter size was lower (P < 0.05) in IS groups in summer, autumn, and winter, and the number of live-born piglets/sow was lower (P < 0.05) for IS sows in the summer and fall. Beneficial effects of group housing on piglet productivity manifested up until the seventh consecutive farrowing and then began to wane. In summary, there was a significantly greater proportion of sows going estrus "on time" (i.e., <7 days) in group housing compared to single stalls but this effect was confined to the second parity sows during the summer and fall months; these results suggest the existence of a seasonal and age-related aspect to sow fertility worthy of further investigation. While both housing systems have their pros and cons, our present results indicate that, in commercial settings, group housing postweaning improved nearly all reproductive parameters of sows.

Coalescence, crystallographic orientation and luminescence of ZnO nanowires grown on Si(001) by chemical vapour transport.

We analyse the morphological, structural and luminescence properties of self-assembled ZnO nanowires grown by chemical vapour transport on Si(001). The examination of nanowire ensembles by scanning electron microscopy reveals that a non-negligible fraction of nanowires merge together forming coalesced aggregates during growth. We show that the coalescence degree can be unambiguously quantified by a statistical analysis of the cross-sectional shape of the nanowires. The examination of the structural properties by x-ray diffraction evidences that the nanowires crystallize in the wurtzite phase, elongate along the c-axis, and are randomly oriented in plane. The luminescence of the ZnO nanowires, investigated by photoluminescence and cathodoluminescence spectroscopy, is characterized by two bands, the near-band-edge emission and the characteristic defect-related green luminescence of ZnO. The cross-correlation of scanning electron micrographs and monochromatic cathodoluminescence intensity maps reveals that: (i) coalescence joints act as a source of non-radiative recombination, and (ii) the luminescence of ZnO nanowires is inhomogeneously distributed at the single nanowire level. Specifically, the near-band-edge emission arises from the nanowire cores, while the defect-related green luminescence originates from the volume close to the nanowire sidewalls. Two-dimensional simulations of the optical guided modes supported by ZnO nanowires allow us to exclude waveguiding effects as the underlying reason for the luminescence inhomogeneities. We thus attribute this observation to the formation of a core-shell structure in which the shell is characterized by a high concentration of green-emitting radiative point defects as compared to the core.

Virological Quality of Irrigation Water in Leafy Green Vegetables and Berry Fruits Production Chains.

This study condenses data acquired during investigations of the virological quality of irrigation water used in production of fresh produce. One hundred and eight samples of irrigation water were collected from five berry fruit farms in Finland (1), the Czech Republic (1), Serbia (2), and Poland (1), and sixty-one samples were collected from three leafy green vegetable farms in Poland, Serbia, and Greece. Samples were analyzed for index viruses of human or animal fecal contamination (human and porcine adenoviruses, and bovine polyoma viruses), and human pathogenic viruses (hepatitis A virus, hepatitis E virus, and noroviruses GI/GII). Both index and pathogenic viruses were found in irrigation water samples from the leafy green vegetables production chain. The data on the presence of index viruses indicated that the highest percentage of fecal contamination was of human origin (28.1 %, 18/64), followed by that of porcine (15.4 %, 6/39) and bovine (5.1 %, 2/39) origins. Hepatitis E virus (5 %, 1/20) and noroviruses GII (14.3 %, 4/28) were also detected. Samples from berry fruit production were also positive for both index and pathogenic viruses. The highest percentage of fecal contamination was of human origin (8.3 %, 9/108), followed by that of porcine, 4.5 % (4/89) and bovine, 1.1 % (1/89) origins. Norovirus GII (3.6 %, 2/56) was also detected. These data demonstrate that irrigation water used in primary production is an important vehicle of viral contamination for fresh produce, and thus is a critical control point which should be integrated into food safety management systems for viruses. The recommendations of Codex Alimentarius, as well as regulations on the use of water of appropriate quality for irrigation purposes, should be followed.

First Report on the Efficiency of Oral Vaccination of Foxes against Rabies in Serbia.

Rabies is one of the oldest known zoonotic diseases that has significant impact on public health, but still remains neglected in Serbia. Rabies virus can infect humans and other mammals and causes inflammation of the brain associated with encephalomyelitis and neurological symptoms. In 2010, Veterinary Directorate (national Competent Authority for animal health in Serbia) has started multi-annual project of oral rabies vaccination of foxes and other wild carnivores (e.g. jackals), as support of long-term programme of eradication of rabies in Serbia, co-funded by EU (financed by Instrument for Pre-Accession Assistance). Monitoring of the effectiveness of oral vaccination campaigns has been carried out in continuation from 2011 and was based on: (i) post-mortem laboratory examination of brain tissue of target animals (foxes, jackals and other carnivores) by fluorescent antibody test (FAT), (ii) detection of antibodies against rabies virus in serum samples by ELISA and (iii) detection of tetracycline biomarker in the mandibles for the evaluation of vaccine bait uptake. From September 2011 to May 2014, the total number of 4943 brain tissue samples, 4241 sera and 4971 mandibles were analysed. Confirmed rabies-positive brains decreased from 10 in 2011/2012 to 6 in 2012/2013 and eventually to 1 positive case in 2013/2014. The seroconversion rate increased from 10.48% (133/1269) in 2011/2012 to 20.11% (362/1800) in 2012/2013 and 42.23% (495/1172) in 2013/2014. Along with the seroconversion, the number of detected tetracycline-positive mandibles demonstrated an increasing tendency in the same period, being 49.67% (682/1373) in 2011/2012, 62.60% (1294/2067) in 2012/2013 and 90.33% (1383/1531) in the monitoring programme carried out in 2013/2014. Presented results confirmed that ORV of foxes and other wildlife in Serbia against rabies was successful and characterized by steady increase of vaccine baits uptake and immunization of animals.

Dynamic changes of carotid artery intima-media thickness and mortality in hemodialysis patients.

INTRODUCTION: Intima-media thickness (IMT) of the carotid artery is a widely accepted parameter for detection and quantification of atherosclerosis. The aim of the study was the evaluation of the impact of changes of IMT on the mortality of patients on hemodialysis. METHODS: The study was organized as a prospective and observational one. Intima-media thickness was determined by ultrasound in 194 patients who were evaluated every year during a three-year period. We analyzed the mortality rate of patients on hemodialysis in relation to their biochemical parameters, demographic and anthropometric characteristics, type of dialysis, smoking habits and statin therapy. RESULTS: Female gender and hemodiafiltration emerged as good predictors of long-term survival. Baseline IMT values were significantly lower than those at the end of the second (p <0.001) and third years of the study (p <0.001). The baseline values positively correlated with uric acid levels (p =0.027) and body mass index (p =0.024), while at the end of the second year, IMT positively correlated with LDL-cholesterol (p =0.037) and triglyceride levels (p =0.018) and body mass index (p =0.045). Patients on hemodiafiltration had significantly higher values for erythrocytes (p =0.047), hemoglobin (p =0.005), creatinine (p =0.048), Kt/V (p =0.026), albumin (p =0.012), LDL-cholesterol (p <0.001), body mass index (p <0.001),and lower IMT values at the end of the first year (p =0.039), compared to patients on bicarbonate hemodialysis. Predictors of death were the duration of hemodialysis (p <0.001), and IMT at the end of the first (p =0.008) and second years of the study (p =0.005). CONCLUSION: Dynamic changes of IMT of the carotid arteries during the first two years were found in our study to be predictors of mortality in patients on hemodialysis. Hippokratia 2015; 19 (2):158-163.

DETERMINATION OF AZOXYSTROBIN AND DIFENOCONAZOLE IN PESTICIDE PRODUCTS.

In this study a high performance liquid chromatographic (HPLC-DAD) procedure has been developed for the simultaneous determination of azoxystrobin and difenoconazole in suspension concentrate pesticide formulations, with the aim of the product quality control. Azoxystrobin, strobilurin fungicide and difenoconazole (cis,trans-3-chloro-4-[4-methyl-2-(1H-1,2,4-triazol-1-ylmethyl)-1,3-dioxolan-2-yl]phenyl 4-chlorophenyl ether), triazole fungicide, are used for the protection of plants from wide spectrum of fungal diseases. For the analysis LC system an Agilent Technologies 1100 Series was used. Good separation was achieved on a Zorbax SB-C18 column (5 µm, 250 mm x 3 mm internal diameter) using a mobile phase consisting of acetonitrile/ultrapure water (90:10, v/v), at a flow rate of 0.9 ml/minute and UV detection at 218 nm. Column temperature was 25 degrees C, injected volume was 1 µl. Retention times for azoxystrobin and difenoconazole were 2.504 min and 1.963 min, respectively. This method is validated according to the requirements for new methods, which include linearity, precision, accuracy and selectivity. The method demonstrates good linearity with r2 > 0.997. The repeatability of the method, expressed as relative standard deviation (RSD, %), was found to be 1.9% for azoxystrobin and 0.5% for difenoconazole. The precision of the method was also considered to be acceptable as the experimental repeatability relative standard deviation (RSD) was lower than the RSD calculated using the Horwitz equation of 1.7% and 1.4% for azoxystrobin and difenoconazole, respectively. The accuracy of the proposed method was determined from recovery experiments through standard addition procedure. The average recoveries of the three fortification levels were 101.9% for azoxystrobin and 103.2% for difenoconazole with RSDs of 1.1% and 1.2%. The method described in this paper is simple, precise, accurate and selective and represents a new and reliable way of simultaneous determination of azoxystrobin and difenoconazole in formulated products.

Monitoring West Nile virus (WNV) infection in wild birds in Serbia during 2012: first isolation and characterisation of WNV strains from Serbia.

West Nile virus (WNV), a neurovirulent mosquito-transmissible zoonotic virus, has caused recent outbreaks in Europe, including Serbia from August until October 2012. Although humans can be infected, birds are the main natural WNV reservoir. To assess WNV circulation in northern Serbia, 133 wild birds were investigated. These comprised resident and migratory birds, collected between January and September 2012 in the Vojvodina province. The birds belonged to 45 species within 27 families. Blood sera (n=92) and pooled tissues from respective birds (n=81) were tested by enzyme-linked immunosorbent assay (ELISA), plaque reduction neutralisation test (PRNT) and real-time reverse transcription-polymerase chain reaction (RT-qPCR). WNV antibodies were detected in seven (8%) sera: four from Mute Swans (Cygnus olor), two from White-tailed Eagles (Haliaeetus albicillas), and one from a Common Pheasant (Phasianus colchicus). Five sera neutralised WNV but not Usutu virus. For the first time in Serbia, WNV RNA was detected by RT-qPCR in pooled tissue samples of eight respective birds. WNV RNA was also derived from an additional bird, after a serum sample resulted infective in cell culture. The total nine WNV RNA positive birds included three Northern Goshawks (Accipiter gentilis), two White-tailed Eagles, one Legged Gull (Larus michahelis), one Hooded Crow (Corvus cornix), one Bearded Parrot-bill (Panarus biramicus), and one Common Pheasant. Phylogenetic analysis of partial E region sequences showed the presence of, at least, two lineage 2 Serbian clusters closely related to those responsible for recent human and animal outbreaks in Greece, Hungary and Italy. Full genomic sequence from a goshawk isolate corroborated this data. These results confirm WNV circulation in Serbia and highlight the risk of infection for humans and horses, pointing to the need for implementing WNV surveillance programmes.

Acoustically driven photon antibunching in nanowires.

The oscillating piezoelectric field of a surface acoustic wave (SAW) is employed to transport photoexcited carriers, as well as to spatially control exciton recombination in GaAs-based nanowires (NWs) on a subns time scale. The experiments are carried out in core-shell NWs transferred to a SAW delay line on a LiNbO(3) crystal. Carriers generated in the NW by a focused laser spot are acoustically transferred to a second location, leading to the remote emission of subns light pulses synchronized with the SAW phase. The dynamics of the carrier transport, investigated using spatially and time-resolved photoluminescence, is well-reproduced by computer simulations. The high-frequency contactless manipulation of carriers by SAWs opens new perspectives for applications of NWs in opto-electronic devices operating at gigahertz frequencies. The potential of this approach is demonstrated by the realization of a high-frequency source of antibunched photons based on the acoustic transport of electrons and holes in (In,Ga)As NWs.

Harmonised investigation of the occurrence of human enteric viruses in the leafy green vegetable supply chain in three European countries.

Numerous outbreaks have been attributed to the consumption of raw or minimally processed leafy green vegetables contaminated with enteric viral pathogens. The aim of the present study was an integrated virological monitoring of the salad vegetables supply chain in Europe, from production, processing and point-of-sale. Samples were collected and analysed in Greece, Serbia and Poland, from 'general' and 'ad hoc' sampling points, which were perceived as critical points for virus contamination. General sampling points were identified through the analysis of background information questionnaires based on HACCP audit principles, and they were sampled during each sampling occasion where as-ad hoc sampling points were identified during food safety fact-finding visits and samples were only collected during the fact-finding visits. Human (hAdV) and porcine (pAdV) adenovirus, hepatitis A (HAV) and E (HEV) virus, norovirus GI and GII (NoV) and bovine polyomavirus (bPyV) were detected by means of real-time (RT-) PCR-based protocols. General samples were positive for hAdV, pAdV, HAV, HEV, NoV GI, NoV GII and bPyV at 20.09 % (134/667), 5.53 % (13/235), 1.32 % (4/304), 3.42 % (5/146), 2 % (6/299), 2.95 % (8/271) and 0.82 % (2/245), respectively. Ad hoc samples were positive for hAdV, pAdV, bPyV and NoV GI at 9 % (3/33), 9 % (2/22), 4.54 % (1/22) and 7.14 % (1/14), respectively. These results demonstrate the existence of viral contamination routes from human and animal sources to the salad vegetable supply chain and more specifically indicate the potential for public health risks due to the virus contamination of leafy green vegetables at primary production.

Characteristics of depression in obese people living in an insecure environment.

BACKGROUND: Obesity and depression are significant characteristics of people living in a state of chronic stress. PURPOSE: Our aim was to determine the characteristics of depression in obese people living in an insecure unstable environment. MATERIALS AND METHODS: The case-control study was organized in two rural environments in Kosovo and Metochia, Serbia. The main criterion for selection of participants was that respondents were more than 18 years old and had a body mass index of 25 kg/m 2 or more. Other anthropometric parameters determined were body weight, height, body fat mass, hip and waist circumference and the waist/hip ratio. The sex, demographic characteristics, profession, marital status, social status, existence of comorbidity, and cigarette smoking habits were recorded, and the arterial blood pressure measured for all participants. In the form of an interview, all respondents answered 17 questions, based on the Hamilton scale for depression. RESULTS: The group of depressed patients was dominated by women (P = 0.009). A significant difference (P = 0.007) was found in relation to profession. Depression was significantly more frequent in those without a regular income (P < 0.001). Depressed patients were significantly older (P = 0.017), more obese (P = 0.04), shorter (P = 0.0001), had a larger hip circumference (P = 0.039) and WHR index (P = 0.049) compared to patients in whom depression was not established. CONCLUSIONS: Depression is a significant characteristic in people living in an insecure environment, more common in women, without a permanent financial income.

Borrelia burgdorferi in ticks and dogs in the province of Vojvodina, Serbia.

Lyme disease is a tick borne zoonotic infection, caused by Borrelia burgdorferi s.l. bacteria. For the transmission of the disease, the presence of ticks is a prerequisite. Lyme borreliosis mostly occurs in people and dogs, but it may occur in other animals. Ticks which carry B. burgdorferi s.l. in Serbia are of the Ixodes ricinus specis. In Serbia, Lyme disease was detected for the first time in the late '80-es. In dogs, clinical symptoms may occur even months after a tick bite, and include weakness, lymphadenopathy, fever, lameness, arthritis, etc. In our survey, we have observed tick and dog populations in the province of Vojvodina (northern part of Serbia). I. ricinus ticks were collected and examined for the presence of B. burgdorferi s.l. in several chosen locations. In addition, blood samples were collected from house dogs and pets from the same locations, and analyzed for the presence of antibodies specific for B. burgdorferi s.l. The results showed a mean infection of ticks of 22.12%, and a mean seroprevalence of Lyme disease in dogs of 25.81%. We conclude that in Vojvodina there is an actual risk of Lyme borreliosis for other animals and humans, because of the persistence of B. burgdorferi s.l. in both tick and dog populations.

Synergistic effects of dehydroepiandrosterone and fluoxetine on proliferation of progenitor cells in the dentate gyrus of the adult male rat.

The 5-HT re-uptake inhibitor (SSRI) fluoxetine and the adrenal hormone dehydroepiandrosterone (DHEA) both increase the proliferation of progenitor cells in the adult hippocampus and also have antidepressant activity. This paper explores the combined ability of fluoxetine and DHEA to affect this process in the dentate gyrus of adult rats. We show that DHEA can render an otherwise ineffective dose of fluoxetine (2.5 mg/kg) able to increase progenitor cell proliferation to the same extent as doses four times higher (10 mg/kg). This synergistic action does not appear to be mediated by alterations in brain-derived neurotrophic factor (BDNF) gene expression; or by TrkB, mineralocorticoid, glucocorticoid, or 5-HT (5HT1A) receptor expression in the dentate gyrus; or by altered levels of plasma corticosterone. In a second experiment, the synergism between DHEA and fluoxetine was replicated. Furthermore, flattening the diurnal rhythm of plasma corticosterone by implanting additional corticosterone pellets s.c. prevented the effect of fluoxetine on progenitor cell division. This was not overcome by simultaneous treatment with DHEA, despite the latter's reported anti-glucocorticoid actions. The cellular mechanism for the potentiating action of DHEA on the pro- proliferative effects of fluoxetine in the adult hippocampus remains to be revealed. Since altered neurogenesis has been linked to the onset or recovery from depression, one consequence of these results is to suggest DHEA as a useful adjunct therapy for depression.

Hand tapping: a simple, reproducible, objective marker of motor dysfunction in Huntington's disease.

Huntington's disease (HD) is a severe neurodegenerative condition in which the impairment in voluntary movement is related to functional disability. Clinical assessment of motor deficit currently relies largely on subjective rating scales without objective measurement. We have developed a quick and easy-to-use hand tapping device that enables measurement of (a) the number of taps in 30 seconds, (b) variability in tapping rhythm and (c) fatigue over the testing period. Initial cross-sectional testing of 178 consecutive HD clinic patients using an early model of the device showed that the total number of taps in 30 seconds correlated with the motor UHDRS (Spearmann's rho, r(s) = -0.81, p < 0.0001) and independence scores (r(s) = 0.78, p = 0.01). Longitudinal data from a small cohort followed over 10 years reveals a correlation between total number of taps in 30 seconds and motor UHDRS over time (rs = -0.49, p < 0.001), and suggests the technique may provide an objective measure of disease progression. Further tests on 15 HD patients and 9 controls were repeated three times in a single day using an updated device. The HD group made significantly fewer taps in 30 seconds (median HD = 79, control = 104, p = 0.009) and had greater variability of inter-tap interval (mean interdecile range HD = 148, control = 56, p = 0.016) compared to controls. Both the total number of taps and variability of inter-tap interval correlated with motor UHDRS. Of vital importance for any potential marker of disease progression is that these tapping parameters were reproducible with repeated measurement. Given that hand tapping parameters differ between HD and control populations, they correlate with motor UHDRS over time and are reproducible, we propose that assessment of hand tapping represents a useful objective adjunct to the clinical assessment of HD patients.

The prevalence of Shiga toxin-producing Escherichia coli in domestic animals and food in Serbia.

Faecal samples of 2660 domestic animals from 116 farms and 956 samples of food were examined for the presence of Shiga toxin-producing Escherichia coli (STEC). STEC was recovered from 126 (15.3%) cattle, 135 (11.3%) pigs, 135 (66.8%) sheep, 31 (73.8%) goats, 4 (1%) chicken, and 15 (1.6%) food samples. Of all STEC isolates, 21.5, 25.8 and 15% produced enterohaemolysin, alpha-haemolysin, and aerobactin respectively, 1.6% displayed localized adherence (LA) to HEp-2 cells, 27.6% were sorbitol negative, and 30% were resistant to antibiotics. Only 14 (3.1%) of the STEC isolates belonged to human infection-associated serogroups (O26, O55, O111, O128 and 0157), designated as enterohaemorrhagic E. coil (EHEC). This study revealed that STEC are prevalent in domestic animals, and to a lesser extent in food of animal origin in Serbia, but the absence of a EHEC phenotypic profile (characteristic serogroup, LA, enterohaemolysin production) in most animal STEC strains may explain the low incidence of human STEC infection in this part of the world.