Identifying superior drought-tolerant olive genotypes and their biochemical and some physiological responses to various irrigation levels

Drought is currently one of the most severe abiotic factors limiting agricultural production. The high rates of population growth and global warming are expected to further exacerbate the threat of drought, especially in areas with a semi-arid climate as in the Middle East region. Selecting genotypes for improved drought tolerance has long been of interest for those involved in horticulture. The present research investigated the reaction of seven 10-year-old olive genotypes to drought stress in Dallaho Olive Research Station, Iran. To determine the reaction of genotypes to drought stress, physiological and biochemical characteristics, fruit and oil yield, and water use efficiency were measured. The results showed that different genotypes react differently to drought stress while drought decreased vegetative and reproductive traits such as shoot length and diameter, relative water content of the leaves, Ca and K percentage, and fruit yield. Finally, Dd₁ and Bn₆ showed the highest oil and fruit yield per hectare and the highest water use efficiency. In addition, Bn₃ had a favorable status in most of the measured parameters. So, they can be suggested as the genotypes that are tolerant of drought stress. The results also showed that olive yield and irrigation management can be improved by applying proper irrigation levels and using tolerant genotypes.     

Matrix-fibril morphology development of polypropylene/poly(butylenes terephthalate) blend fibers at different zones of melt spinning process and its relation to mechanical properties

Different shapes of dispersed phase such as sphere, laminar and fibrillar can form in the matrix phase of polymer blends. Production of blend fibers in melt spinning process can result more effective in fibrillar phase morphology formation than in other processes. In this research, the matrix-fibril morphology development during the melt spinning of polypropylene/poly(butylenes terephthalate) was studied. The shapes of blend dispersed phase collected from different zones of the melt spinning line were evaluated by scanning electron micrographs (SEM) and rheological mechanical spectra (RMS). The results showed that fibrillar shape could not be created in the PP/PBT blend fiber samples exited from the spinneret orifice (gravity spun fibers) at low contents (5 percent) of the PBT dispersed phase. However, a complete fibrillar structure was formed in all the as-spun PP/PBT blend fiber samples (melt drawn). The rheological evaluations confirmed a network structure resulting from fibril formation for the samples with high contents (20–40 %) of the PBT dispersed phase and the formation of spherical shape with low contents (5–10 %) of the PBT dispersed phase in matrix of the blend fibers. It was observed that the flow fields of processing zones and blend ratio, in producing the blend fibers, have intensive effects on morphological variations; besides there was a strong relation between the mechanical and morphological properties.     

A new technique for tracing the concentration-distance variations in the cross section of polyamide rods by using a conventional scanner

A new method for determining the dye distribution in the cross section of polyamide rods from the scanner data is presented. Three commercial disperse dyes are used for dyeing purposes and two series of dyed samples are prepared. The first set is the samples with the full diffusion of dyes within the cross section of rods that used as the reference samples while the second set includes samples with different depths of penetrations, hence they benefit from non homogenous dye distribution in their cross sections. A conventional scanner is characterized with the ColorChecker SG and the transformation matrix is computed to convert the RGB values of samples to the CIEXYZ data. The spectral reflectances as well as the RGB values of the cross sections of the full diffused dyed samples are measured and the classical version and the weighted version of principal component analysis technique are employed to estimate the spectral behaviors of homogenous dyed samples from the CIEXYZ values obtained from the corresponding RGB data. Finally, the well known Kubelka Munk equation is employed to estimate the concentration of dyes in the cross sections of samples. The work is extended to non homogenous dyed samples to find the spatial distributions of dyes over the cross sections of rods. Similar to full diffused dyed samples, the spatial reflectance spectra of the cross sections are firstly estimated from the measured RGB values and then the spatial concentrations are computed. The plotted concentration-distance profiles confirm the classical variations of dye concentrations over the cross sections of dyed rods similar to those that are obtainable by conventional methods such as multiple membranes and Boltzmann-Matano as well as laser scanning confocal microscopy methods.     

Characterization of beta-lactamases from urinary isolates of Escherichia coli in Tehran

BACKGROUND: Knowledge of antimicrobial resistance patterns in E. coli, the predominant pathogen associated with urinary tract infections (UTI) is important as a guide in selecting empirical antimicrobial therapy. METHODS: To describe the antimicrobial susceptibility of E. coli associated with UTI in a major university hospital in Tehran (Iran), seventy-six clinical isolates of E. coli were studied for susceptibility to beta-lactam antibiotics by the disc diffusion method and Minimal Inhibitory Concentrations determination. RESULTS: All isolates were resistant to ampicillin, amoxicillin and oxacillin. Resistance to the other tested antibiotics was shown to be 93.4% to cefradine, 76.3% to carbenicillin, 47.3% to cefazoline, 50% to cefalexin and 32.8% to cephalothin while 1.3% expressed resistance to cefoxitime, and 2.6% were resistant to ceftizoxime and ceftriaxone. Two isolates (2.4%) harbored extended spectrum beta-lactamases (ESBL) shown by the double disc diffusion method. Substrate hydrolysis by ultra violet spectroscopy showed that 87.4% harbored penicillinases, 9% produced cephlosporinases and 3.6% degraded both substrates. Clavulanic acid inhibited enzyme activity in 82.9%, of which 78.95% was penicillinases (group IIa) and 3.95% was cephalosporinases (group IIb) of the Bush classification system. The rest of the isolates (6.58 %) were placed in group IV beta-lactamases. No group III beta-lactamase was found, as EDTA inhibited none of the enzymes. DNA amplification by polymerase chain reaction using specific primers for ampC, TEM and SHV type beta-lactamases for all of the isolates showed that 47 organisms (60%) carried the TEM gene and 18 isolates (24%) harbored blaTEM and ampC genes. About 26% of the organisms harbored SHV type enzymes. CONCLUSION: These results indicate that E. coli can posses a variety of beta-lactamases that are responsible for beta-lactam resistance.     

Salvia officinalis hydroalcoholic extract improved reproduction capacity and behavioral activity in rats exposed to immobilization stress

This study was conducted to evaluate the Salvia officinalis hydroalcoholic extract on fertility capacity and behavioral features in rats exposed to immobilization stress. Male rats were randomly divided into five groups; Control; Stressed rats; and Stressed rats received 50, 100 and/or 200 mg/kg bw S. officinalis hydroalcoholic extract. To induce stress, rats were immobilized for 49 days and received S. officinalis extract orally. On day 56, we analyzed behavioral tests and evaluated reproduction capacity by measuring LH, FSH, and testosterone. Sperm parameters such as motility, viability, and total count were also determined. Bodyweight changes were also calculated on day 56. Male rats from different groups were mated with healthy female rats. Data showed that the use of 100 and 200 mg/kg bw S. officinalis extract in stressed rats increased bodyweight gain and improved behavioral disorders compared to control‐matched groups (p < .05). Besides, administration of 100 and 200 mg/kg bw S. officinalis extract had the potential to improve sperm parameters and fertility capacity in stressed rats (p < .05). Decreased testosterone levels were blunted in the stressed rats that received plant extract coincided with the reduction of LH and FSH compared to control‐matched stressed rats (p < .05). We found neutral effects in stressed rats that received 50 mg/kg bw plant extract. Collectively, the hydroalcoholic extract of S. officinalis could improve the fertility capacity and behavioral features under stressful conditions in a dose‐dependent manner.     

Effect of dietary supplementation of whole flaxseed on sperm traits and sperm fatty acid profile in aged broiler breeder roosters

The objective of this study was to evaluate the effect of dietary supplementation of whole flaxseed on sperm traits and sperm fatty acid profile in aged broiler breeder roosters. Twelve Ross 308 broiler breeder roosters (age: 52 weeks; weight: 4,900 ± 210 g) haphazardly allotted to three dietary treatments (each treatment contained four replicates and one bird in each replicate) for six weeks. Treatments were different levels of flaxseed (0% flaxseed [GFL0], 2% flaxseed [GFL2] and 4% flaxseed [GFL4]). The feed intake quadratically decreased (p < .05) with increasing whole flaxseed levels for the period (58 to 60 weeks). Sperm traits (semen volume and sperm concentration, sperm total and forward motility, sperm viability and morphology, sperm plasma membrane functionality) were evaluated every two weeks (four times), and sperm fatty acid profile was assessed at the end of the experiment. Semen volume, sperm concentration and sperm morphology were not affected by treatments. On week 60, GFL2 group showed a significantly lower percentage of total and progressive sperm motility and sperm membrane functionality in comparison with the control and GFL4 groups. Also, sperm viability was lower in GFL2 group compared with other groups on week 58 (p < .05). In terms of sperm fatty acid profile, GFL2 group significantly reduced the percentage of linoleic acid (C18:2 [n-6]) in comparison with other groups. However, any of the other fatty acids were not affected by dietary flaxseed. In conclusion, dietary supplementation of whole flaxseed could not improve the quality of aged broiler breeder roosters' sperm in this study, nor it could alter the sperm fatty acid profile; thus, it seems necessary to use some antioxidants such as vitamin E in the diet of aged broiler breeder roosters, when supplementing the diets with oils or oilseeds such as flaxseed.     

Lipid stability and antioxidant profile of microsomal fraction of broiler meat enriched with α-lipoic acid and α-tocopherol acetate

The importance of the linkage between nutrition and health is a hot issue. Like other food-related sectors, the meat industry is undergoing foremost transformations, driven among other things by changes in consumer requirements. The present study was designed to evaluate the lipid stability and antioxidative potential of leg and breast microsomal fraction of broiler meat fed on ALA and ATA. For the first 3 weeks of growth, broilers were fed on feed supplemented with ATA (200 mg/kg of feed) and during the last 3 weeks broilers were fed on feed supplemented with ALA (25, 75, 150 mg/kg of feed) and a constant level of ATA (200 mg/kg of feed). The body weight of the carcass was measured after every week of growth until 6 weeks. Positive correlation between the antioxidant activity and the TPC was observed. Higher values of TBARS were detected in leg muscles than in breast muscles. HPLC data revealed ALA and ATA contents were higher in T(4) (leg, 5.55 ± 0.19 and 3.87 ± 0.15 μg/mg of protein; breast, 5.63 ± 0.20 and 2.03 ± 0.10 μg/mg of protein, respectively) and lowest in T(5) (ALA, leg, 1.40 ± 0.06 μg/mg of protein; breast, 1.54 ± 0.05 μg/mg of protein; ATA, leg, 1.25 ± 0.06 μg/mg of protein; breast, 0.63 ± 0.008 μg/mg of protein), in which the only oxidized oil was used. Oxidized oil in feed reduced weight gain and increased TBARS, whereas TPC, DPPH, ALA, and ATA values decreased in both leg and breast meat.     

Wool characteristics in the third generation of Arkharmerino × Ghezel and Arkharmerino × Moghani crossbreed sheep

This investigation was conducted to evaluate the comparative productive performances and effect of some environmental factors on wool characteristics of Arkharmerino × Ghezel (Ar × Gh) and Arkharmerino × Moghani (Ar × Mo) crossbreed sheep. The mid-side fleece samples taken from animals during 2 years (2007–2008) were analyzed. Each sample was measured for average fiber diameter, fiber diameter variability, staple length, proportion of medullated fiber, proportion of kemp, and comfort factor. The comparative values for these fleece characteristics in F₃ generation Ar × Gh were 28.78 ± 0.48 μm, 36.84 ± 1.16%, 11.94 ± 0.35 cm, 7.07 ± 0.93%, 1.02 ± 0.23%, and 68.93%, respectively; while those traits were 29.79 ± 0.43 μm, 41.86 ± 1.16%, 11.96 ± 0.37 cm, 8.13 ± 1.06%, 2.71 ± 0.45%, and 63.33 ± 3.66% for Ar × Mo, respectively. The effects of genotype, sex, birth type, and year of birth were analyzed. Genotype had a significant (P < 0.01) effect on average fiber diameter and proportion of kemp, and Ar × Gh crossbreeds had lower diameter with less proportion of kemp. The two differences in fiber characteristics that were attributable to sex were fiber diameter variability and proportion of medullated fiber, and females had higher measure than males for both traits. Statistical analysis showed that crossbreeding with Arkharmerino generally had positive effects on the fleece favored to be used in the hand woven authentic carpet production.     

Molecular survey of <Emphasis Type="Italic">Toxoplasma</Emphasis> infection in sheep and goat from Fars province,Southern Iran

Toxoplasmosis is a widespread zoonotic disease that causes significant morbidity and mortality in human fetus and in immunocompromised patients. Moreover, it becomes a major cause of abortion in sheep and goats. Since consumption of meat of infected lamb and goat is considered as the main sources of human infection in Iran, this study was undertaken to determine the prevalence of Toxoplasma infection in edible tissues of sheep and goats in Shiraz in 2008. Samples of brain, tongue, liver, and muscles of neck, intercostals, and femoral were taken from 56 sheep and 22 goats and tested by PCR. The total prevalence of Toxoplasma infection among animals was found to be 33.3%. Five out of 22 goats (22.7%) and 21 out of 56 sheep (37.5%) were infected by Toxoplasma. Differences between the prevalence rate of infection among females (nine out of 14 = 46%) and males animals (12 out of 45 = 29.5%) was significant (P = 0.013). Furthermore, a positive correlation was found between the age of animals and the rate of infection; animals greater than 2 years old showed a higher rate of infection (47%) in comparison with those less than 2 years old (25%, P = 0.04). The highest infected tissue was tongue (21.8%) followed by brain (19.2%) and femoral and intercostal muscles (17.9%). This study demonstrated a high level of Toxoplasma infection in slaughtered animals in Shiraz and these should be considered as the main sources of infection for human population in the region.