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Coagulase-negative staphylococci (CNS) are the most prevalent mastitis pathogens. However, virulence characteristics of CNS
have not been well determined. The presence of genes for enterotoxins (sea-sej), toxic shock syndrome toxin-1 (tst), the exfoliative toxins (eta, etb), Panton–Valentine leukocidin (pvl) and mecA of CNS species isolated from cows and ewes with subclinical mastitis was investigated in this study. A total of 121 CNS
(81 cows, 40 ewes) representing 18 different Staphylococci species were examined by PCR, and 38.1% (33 cows and 13 ewes) of CNS isolates had one or more se genes. The difference between percentages for SE toxin genes of CNS strains isolated from cows (40.7%) and ewes (32.5%) was
not statistically significant (P > 0.05; χ
2 = 0.380). It was found that S. simulans isolates had the highest prevalent se genes. Furthermore, the most common SE gene types was seh-sej. In this study, none of the isolates harbored the toxic shock syndrome toxin gene (tsst) and the exfoliative toxin genes (eta, etb). Five cow (6.17%) and three ewe CNS (7.5%) isolates had mecA gene. Three cow (3.7%) and two ewe CNS (5.0%) isolates had pvl gene. In conclusion, the present study showed that CNS species isolated from cows and ewes could serve as potential reservoir
of se, mecA, and pvl genes. 相似文献
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Changes in the acetoclastic methanogenic activity in the effluentfrom an upflow anaerobic filter (UFAF) were studied throughout a 36 week operating period. The UFAF formed the second phase of a two-phase laboratory-scale anaerobic treatment system. TheSpecific Methanogenic Activity (SMA) test was used to measurethe acetoclastic methanogenic activity of the biomass washed outfrom the UFAF. Throughout the operating period, the SMA testswere carried out at different organic loading rates (OLR) up to6.7 kg COD m-3 d-1 and upflow velocities (UV), 5 m d-1 and 15 m d-1. The results showed that thebiomass washed out from the UFAF consisted of up to 55%(considered as a draft value) acetoclastic methanogens producing550 mI CH4 g-1 VSS d-1. This high acetoclasticmethanogenic activity measured in the effluent might have beendue to the existence of Methanosaeta (formerly Methanothrix) species. Towards the end of operation,Epifluorescence Microscopic examinations in the effluent revealedthat Methanococcus species were the most dominant groupfollowed by medium rods and short rods, filaments and long rodsand the least dominant Methanosarcina species. Theperformance of the UFAF was not adversely affected by the loss ofthe active biomass and changes in their composition. The UFAFsystem achieved over 85% COD removal efficiency at thehighest OLR of 6.7 kg COD m-3 d-1 and UV of 15 m d-1. Throughout most of the operation, methane yield rangedfrom 0.28–035 m3 CH4 kg-1 CODremoved. 相似文献
3.
Murat Ali Turan Süleyman Taban Günsu Barişik Kayin Nilgün Taban 《Journal of plant nutrition》2018,41(11):1351-1357
A greenhouse experiment was conducted with three doses of boron (0, 1, and 10 mg B kg?1 in the form of boric acid (H3BO3). Durum wheat (Triticum durum L. cv: Çakmak-79) and bread wheat (Triticum aestivum L. cv: Gerek-79) cultivars were used as plant material. B toxicity symptoms strongly appeared in durum wheat compared to bread wheat. Applications of B at 1.0 mg B kg?1 stimulated and increased the dry weights of both the cultivars, while high level B application (i.e., 10 mg B kg?1) depressed and decreased the dry weights significantly. B concentration and uptake in the leaf tip were increased with an increase in B application, whereas calcium (Ca) concentration and uptake were decreased in both the cultivars. It was observed that a substantial amount of B was accumulated in the plant cell wall. As similar to leaf tips, B concentrations in the cell wall also increased with B application, whereas Ca concentration was decreased. 相似文献
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Ünal N Askar Ş Macun HC Sakarya F Altun B Yıldırım M 《Tropical animal health and production》2012,44(3):573-579
The aims of this study were to determine the existence of pvl gene, some toxin genes, and mecA gene in Staphylococcus aureus strains isolated from sheep milk and to examine antimicrobial resistance profiles in staphylococci from sheep and goats'
milk. The milk samples were collected from 13 different small ruminant farms in Kirikkale province from February to August
2009. A total of 1,604 half-udder milk samples from 857 ewes and 66 half-udder milk samples from 33 goats were collected.
Staphylococcus spp. were isolated and identified from the samples. Toxin genes and mecA gene among S. aureus strains were determined by PCR. Antimicrobial susceptibility of staphylococci was examined by the disk diffusion method on
Mueller-Hinton agar, and interpreted according to the Clinical Laboratory Standards Institute (CLSI) guidelines. The prevalence
of subclinical intramammary infection in both ewes and goats was 5.2%. The most prevalent subclinical mastitis agents were
coagulase-negative staphylococci and S. aureus with prevalences 2.8% (n:46) and 1.3% (n = 21), respectively. The prevalence of resistances in isolated Staphylococcus spp. to penicilin G, tetracycline, erythromycin, gentamicin, and enrofloxacin were found as 26.9% (18), 7.5% (5), 6.0% (4),
3.0% (2), and 1.5% (1), respectively. Only 3 of the 21 S. aureus ewe isolates (13.4%) were shown to harbor enterotoxin genes being either seh, sej or sec. However, fourteen (66.6%) of the 21 S. aureus isolates had pvl gene while none of the isolates harbored mecA gene. In conclusion, Staphylococci were shown to be the most prevalent bacteria isolated from subclinical mastitis of ewes and goats and these isolates were
susceptible to most of the antibiotics. In addition, S. aureus strains isolated from ewes were harboring few staphylococcal enterotoxin genes. However, Panton–Valentine leukocidin produced
by S. aureus could be an important virulence factor and contribute to subclinical mastitis pathogenicity. 相似文献
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Can ÖD Öztürk Y Öztürk N Sagratini G Ricciutelli M Vittori S Maggi F 《Fitoterapia》2011,82(4):576-584
This present study was undertaken to examine treating effects of St. John's Wort (SJW) extract on nociceptive perception of STZ-diabetic animals based on its potential antidiabetic and antinociceptive activities. One week administrations of SJW extract (125 and 250 mg/kg) induced significant decrease in high blood glucose levels of three weeks STZ-diabetic rats and improved their dysregulated metabolic parameters. In addition, SJW extract treatment caused restoration in the mechanical hyperalgesia of diabetic animals. These findings provide a rationale for the traditional use of SJW against diabetes and display the potential of this plant as a new drug candidate/source for the treatment of diabetic pain. 相似文献
6.
Inci Arıkan Nilgün Kasifoglu Selma Metintas Cemalettin Kalyoncu 《Tropical animal health and production》2010,42(4):669-675
The aim of this study is to determine the knowledge, beliefs, and practices of a population living in a rural area in regards
to tick bites and Crimean-Congo hemorrhagic fever (CCHF). The study was conducted in a rural area located in Central Anatolia
in the region of Eskişehir. A total of 1,500 individuals aged 20 years and older chosen by a stratified random sample were
enrolled. A questionnaire was administered in person. In 264 (17.4%) participants, there was a history of being bitten by
a tick. This rate was higher in older persons, males, married persons, and farmers. The most commonly reported protective
behavior was wearing long sleeves and long pants when wandering in rural areas (65.1% of participants). The least commonly
reported behavior was using insect repellent on skin or clothes (3.3% of participants). Only 799 participants (54%) had heard
about CCHF as a disease associated with ticks. Females, those with primary school education, housewives, and male farmers
had a high frequency of having heard about CCHF. Tick bites and CCHF are important public health problems, yet the current
knowledge of these problems is not sufficient in populations living in rural areas of the Middle Anatolian Region of Turkey. 相似文献
7.
Control of regular cropping in apple is considered critical for fruit growers to ensure their economical sustainability. Irregular flowering can be mitigated by plant growth regulators thanks to their promotion or inhibition effects. In this study, responses of GA4+7 and ethephon on alternate bearing in ‘Golden Delicious’/M9 were examined. GA4+7 and ethephon were applied on the same trees during three consecutive years (2010–12). Flowering, yield, shoot growth, and also some fruit quality parameters were assessed. GA4+7 appeared to be more effectual to regulate alternate bearing. The alternate bearing index calculated with yield in successive years was high in control (0.91), moderate in ethephon (0.71), and low in GA4+7 treated trees (0.41). Modified alternate bearing index, based on cluster number, indicated moderate intensity in GA4+7 (0.53) and high intensity in the others. Although GA4+7 reduced crop density at about 50%, there was little variation in yield per tree and crop efficiency due to increasing of fruit size. GA4+7 did not increase shot length after establishment of equilibrium between vegetative and generative growth in 2012. Ethephon slightly reduced vegetative growth and relatively increased fruit size due to the decrease of fruit set. 相似文献
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