Identification of Helicobacter spp. in oral secretions vs. gastric mucosa of stray cats

The definite mode of transmission of Helicobacter infection is largely unknown. This study was carried out primarily, to determine the existence of Helicobacter spp. in the oral secretions of stray cats as one of the possible routes of transmission and secondly, to evaluate the accordance between oral and gastric colonization of Helicobacter spp. in these cats. Forty-three adult stray cats were thus studied for the presence of Helicobacter species by quantitative rapid urease test (RUT), cytology and PCR. Helicobacter spp. were found in the oral secretions and gastric biopsies of 93% and 67.5% of the stray cats, respectively. There was not, however, any agreement observed between Helicobacter colonization at these two locations, at neither genus nor species level. These findings suggest that the oral cavity is routinely exposed to transient forms of bacteria and may temporarily harbor Helicobacter spp. Thus, oral cavity as a source of Helicobacter spp. may act as a reservoir for transmission and may not necessarily reflect the colonization status of the gastric mucosa.     

Identification and antimicrobial susceptibility patterns of bacteria causing otitis externa in dogs

Bacterial agents are considered important pathogens causing external otitis in dogs. It is essential to carry out bacterial culture and antimicrobial susceptibility test in the case of otitis externa, particularly for chronic or recurring cases. Sterile swab samples were obtained from terminal part of vertical ear canals of 74 dogs with otitis externa for cytology, bacterial culture and antimicrobial susceptibility test. Cytologic smears were stained using Gram and Giemsa staining methods. Aerobic bacterial culture performed on blood agar and MacConkey agar. Among total number of 92 isolated bacteria, 68 were Staphylococcus intermedius. Other isolated bacteria included: Pseudomonas aeruginosa, Proteus mirabilis, Escherichia coli, Pasteurella canis, and six other species of coagulase-negative Staphylococcus. Antimicrobial susceptibility test were performed for all isolated bacteria using 14 antibiotics. Based on the results of this study, all isolated Staphylococcus spp. were sensitive to amikacin, enrofloxacin, and rifampin, and had low resistance to gentamicin, cephalothin and ceftriaxone. More than half of gram-positive isolates were resistant to penicillin and ampicillin. Generally, all isolated gram-negative bacteria, were sensitive to amikacin and enrofloxacin, and had low resistance to ceftriaxone and gentamicin. They were highly resistant to penicillin, eythromycin, and cephalothin. Regarding the results of this study, in cases of uncomplicated otitis externa, it is possible to select antimicrobial drugs merely based on cytology, but it is recommended to perform bacterial culture and antimicrobial susceptibility test. However, in complicated or refractory cases, antimicrobials should be selected based on bacterial culture and antimicrobial susceptibility test.     

Phenotypic and genotypic properties of Escherichia coli isolated from colisepticemic cases of Japanese quail

This study was conducted to characterize the Escherichia coli isolates from colisepticemic Japanese quails. One hundred and nine E. coli were isolated in pure culture from heart blood of dead Japanese quails. The sampled birds were originated from four different farms. Antibiotic resistance pattern of E. coli isolates were determined against nine antibacterial agents. Phylotype and virulence genes of the isolates were detected by polymerase chain reaction. By disc diffusion method, all of the isolates showed resistance to three or more antibiotics, and 19 different patterns of multiple drug resistance were observed. Phylotyping of the most prevalent multiple drug-resistant isolates revealed that they mostly belonged to phylogroups A (A₁ subgroup). The E. coli isolates belong to four phylogenetic groups: A (55.0%), B1 (18.3%), B2 (17.4%), and D (9.2%). Eighty-nine (81.7%) isolates were distributed in five phylogenetic subgroups including 22 (20.2%) in A₀, 38 (34.9%) in A₁, 19 (17.4%) in B2₃, 7 (6.4%) in D₁, and 3 (2.8%) in D₂. The examined E. coli isolates exhibit at least one of the virulence genes tested, whereas three most prevalent genes were crl (94.5%), fimH (89.0%), and iutA (51.4%), respectively. The genetic marker for Afa (afaI B-C), S (sfa/focD-E), and P (papE-F) fimbriae were found in one, four, and ten isolates, respectively. Thirteen different combinations of virulence gene were observed, where combination of crl and fimH genes was the most prevalent pattern. None of the isolates contained the ipaH, stx1, stx2, and eaeA genetic markers. In conclusion, E. coli strains could be considered as a causative agent of mortality in quail farms. In conclusion, E. coli isolates from colisepticemic quails are distributed in different phylogroups, are resistant to combinations of antibiotic agents, and contain several virulence genes.     

Prediction of soil saturated water content using evolutionary polynomial regression (EPR)

The measurement of saturated water content (SWC) is necessary in the estimation of soil water retention and unsaturated hydraulic conductivity curves. In several studies, pedotransfer functions (PTFs) were developed to predict SWC. Among them, evolutionary polynomial regression (EPR) is one that can operate on large quantities of data in order to capture nonlinear and complex interactions between the variables of the system. In this study, the evolutionary data-mining technique was used to derive new PTFs and different methods were evaluated, such as the soil porosity method, Rosetta method, and others, for the estimation of SWC. For this purpose, 270 soil samples (3:1 ratio for development and validation) from three data sets were used. Among 190 PTFs provided by EPR, one equation with the highest accuracy and the least number of inputs was selected. The EPR predictions were compared with the experimental results as well as the PTFs proposed in previous studies. Comparison of the statistical indicators showed that the ‘proposed PTF’ and ‘porosity method’ are the best and worst methods for the prediction of SWC, respectively. Also, good predictions were achieved from the proposed approaches by the groups of Scheinost, Vereecken, and Williams.     

Evaluation of HYDRUS-2D model to simulate the loss of nitrate in subsurface controlled drainage in a physical model scale of paddy fields

Agriculture is a major source of nitrogen usage and release to environment. Due to the effect of water movement on solute transport, investigating the effect of different management scenarios of irrigation and drainage could be useful for reducing nitrate loss and environmental pollution. This study is a scientific attempt to assess the ability of HYDRUS-2D model to simulate the effect of subsurface controlled drainage on nitrate loss of paddy fields. So, two physical models with difference in depth of subsurface controlled drainage (40 and 60 cm) were constructed. The tanks were filled with loam silty soil texture and then transplanted rice. 90 kg/ha potassium nitrate fertilizer was added in two stages of rice growth. Mid-season drainage was applied 26 days after transplantation. After 17 days, drains were closed again and applied flooded irrigation with 5-cm water stagnant layer above soil surface. During experiment, nitrate concentration of drain water was measured. HYDRUS-2D was calibrated with measured data in 60 cm drain depth and validated with 40 cm drain depth. HYDRUS-2D could simulate nitrate concentration with the coefficient of determination 0.95 and 0.89 in calibration and validation stages, respectively. The comparison between the volume of drain water and nitrate concentration from the drains in the depths of 40 and 60 cm indicated lower nitrate load in depth of 40 cm. The results obtained proved that the presence of hardpan layer in depth of 25 cm rather than the absence of it causes increase in 3 % of average nitrate concentration and reduce in 17 % of water discharge.     

Growth and flower quality of four Rosa hybrida L. cultivars in response to propagation by stenting or cutting in soilless culture

Performance of four Rosa hybrida L. cultivars (‘African Dawn’, ‘Ilios’, ‘Maroussia’ and ‘Soprano’) was evaluated. They were grown either on their own roots or grafted (stenting) onto Rosa canina L. ‘Inermis’ rootstock in a polyethylene greenhouse with hydroponics system. Parameters of plant growth and flower quality were investigated for two successive harvesting years (2005 and 2006). Results indicated that, all the cultivars were superior for most of the parameters studied when grafted onto rootstock compared to being on their own roots. Flowering stem fresh weight and diameters, flower fresh and dry weight, flower diameter and length, petal number, leaf chlorophyll content and quality index were higher in grafted plants compared to those propagated by cuttings. However, highest flowering stem length and number were observed in plants propagated by cutting, although not significant as compared with stenting method.     

Improving dairy yield predictions through combined record classifiers and specialized artificial neural networks

A multi-network system, comprising a neural classifier and two specialized neural predictors, was developed for prediction of milk yield from monthly records of Holstein dairy cattle. The classifier categorized records based on high- (≥9000 kg) and low-yields (<9000 kg) after which each set of classified records was fed to a network specialized, or semi-specialized, in prediction of yields for that category. Two differently trained classifiers were developed and compared; one trained with records covering the entire range of milk production, and the other with yields bordering on the cut-off point value of 9000 kg. Training files for the specialized predictors included records from only one yield category while those of the semi-specialized networks contained some records from the other category as well. The classifier trained with border cut-off point yields, had a considerably higher classification rate than the other (99.7% versus 92.3%). In the case of the specialized networks, the addition of records from the opposite category to the training files slightly degraded predictions for the records in the category of their specialization, but considerably improved those of the misclassified records. When misclassifications were marginal, however, the specialized networks produced the highest overall performance. Compared to a network trained with mixed records the combined classifier-predictor system improved the results, although it required an increase in development time.     

The analysis of <Emphasis Type="Italic">groEL</Emphasis> gene in <Emphasis Type="Italic">Salmonella enterica</Emphasis> subspecies <Emphasis Type="Italic">enterica</Emphasis> serovar Typhimurium isolated from avians by PCR-Restriction Fragment Length Polymorphism method

Salmonella enterica subspecies enterica serovar Typhimurium causes food-borne outbreaks and systemic diseases in humans and animals. groEL gene (also known as mopA gene in S. Typhimurium), possessing conserved sequence, plays an important role in invasion of bacteria. The purpose of present study was to identify the polymorphism of groEL gene among different avians in different regions by PCR-RFLP method. Fifty two S. Typhimurium isolates (Broiler (n = 13), Layer (n = 12), Duck (n = 5), Goose (n = 5), Sparrow (n = 8), Canary (n = 3), Pigeon (n = 5) and Casco parrot (n = 1). were identified using serotyping as well as multiplex-PCR. Then, amplification of groEL gene performed and amplified products subjected to restriction digestion with BsuRI enzyme. Three RFLP profiles, A, B and C, generated DNA fragments between approximately 100–1,000 bp in size, were observed. The RFLP profile A was observed in 35 (67.3%), profile B in 14 (26.9%) and profile C in 3 (5.77%) of isolates. S. Typhimurium isolates recovered from 13 broilers (two of which profile A, 9 profile B and 2 profile C) and from 8 sparrows (two of which profile A, 5 profile B and 1 profile C) showed all three profiles, but 12 layers and other avians (including Canary (n = 3), Goose (n = 5), Duck (n = 5), Pigeon (n = 5) and Casco parrot (n = 1)) showed profile A. None of these profiles was allotted for a special region. The result of present study showed that S. Typhimurium undergoes genetic mutations in groEL gene under unpleasant milieu in different regions and in different avians. Thus, genetic diversity, despite conserved nature of groEL gene in S. Typhimurium, may exist but it depends on the condition where bacteria have settled. To our knowledge, three RFLP profiles of groEL gene generated by BsuRI restriction enzyme were not reported previously.     

Variability of amino acid digestibility of lupin and pea grains in caecectomised laying hens

1. The objective of this study was to investigate the variations in amino acid (AA) digestibility of lupin and pea grains in caecectomised laying hens. The relationship between AA digestibility and chemical constituents of the grains was determined.

2. Twelve variants of lupins and peas were each added to a basal diet at a concentration of 300 g/kg, at the expense of maize starch. The lupin and pea variants were separately investigated in two subsequent trials. Each trial consisted of two 7 × 7 Latin squares, each comprising the basal diet and six diets with lupins or peas.

3. Fourteen caecectomised laying hens (LSL-classic) were individually housed in metabolism cages and 120 g/d of experimental diets were provided for eight days. During the last four days, excreta were collected quantitatively and feed intake was recorded. A regression approach was used to determine the AA digestibility of the lupin and pea variants.

4. Amino acid digestibility of the lupins and peas was high, although significant differences in AA digestibility among the lupins and peas were detected. The digestibility of lysine was in the range of 0.87–0.91 and 0.87–0.93 for lupins and peas, respectively. The digestibility of methionine in lupins and peas varied between 0.80–0.88 and 0.72–0.90. Variations in AA digestibility in peas were more pronounced than in lupins.

5. Significant correlations between chemical constituents of lupins, such as alkaloids, and AA digestibility were detected in some cases, without a consistent pattern. In peas, tannin concentration and the insoluble protein fraction were negatively correlated with digestibility of some AAs, but only when one colour flower variant was considered. Trypsin inhibitor activity in peas was negatively correlated with AA digestibility, particularly for the white flower variants.     

Effects of different irrigation intervals and weed control on yield and yield components of safflower (Carthamus tinctorius L.)

A two-year (2008–2009) field experiment was conducted to determine the effect of irrigation management and weed control on yield and yield components of safflower. The experiment was conducted as a split-split plot arranged in a randomized blocks design with three replications. There were two treatments (weedy and weed free) and four irrigation interval water managements (7 days for all stages, 15, 22 and 28 days after six-leaf stages). The results indicated that grain yield was 29% higher in weed-free plots than in weedy plots. Weed competition reduced yield components such as primary branches, petal weight and number of capitulum per plant. Increasing the irrigation interval to 15 days at the six-leaf stage had no significant effects on grain yield, but grain yield decreased by 18 and 29.8% with increases in the irrigation interval to 22 and 28 days, respectively. An increased irrigation interval >15 days had negative effects on yield components like number of capitulum per plant, petal weight and number of primary branches. The highest grain yield (3703 kg ha^?1) was obtained in the weed-free plot, and there was no significant difference between 7- and 15-day irrigation intervals.