Synergistic effect of Beauveria bassiana and spirodiclofen on the two-spotted spider mite (Tetranychus urticae)

The two-spotted spider mite, Tetranychus urticae Koch (Acari: Tetranychidae), is one of the most important pests in agriculture. Due to its short life cycle and high reproductive rate, this pest has become resistant to most acaricides. Therefore, finding alternative control strategies for this damaging pest is necessary. Application of microbiological agents with minimum concentrations of acaricides is a very suitable tactic in integrated pest management. In the present study, lethal effects of a chemical acaricide – spirodiclofen, and an Iranian strain of the entomopathogenic fungus Beauveria bassiana, were evaluated on different life stages of the two-spotted spider mite on two host plants, bean and cucumber. In the next step, compatibility of acaricide with the fungus was studied regarding conidial germination and vegetative growth of the fungus in the presence of different concentrations of the acaricide. Finally, the acaricide at rates of LC₂₅ with the fungus at LC₅₀ were sprayed on adult female mites. The results showed that immature stages of T. urticae were more susceptible to the acaricide whereas the adults were more susceptible to the fungus. Also, mites reared on cucumber were significantly more susceptible to the acaricide and fungus than those reared on bean. Spirodiclofen and the fungus had a synergistic effect; percentage of mortality for fungus infection was 48.6% and 53.5% on bean and cucumber, respectively, while it was 80.6% on bean and 84.5% on cucumber when the mite was sprayed with both the fungus and the acaricide.     

Effects of tramadol on the minimum alveolar concentration of sevoflurane in dogs

ObjectiveTo evaluate the effect of tramadol on sevoflurane minimum alveolar concentration (MAC_SEVO) in dogs. It was hypothesized that tramadol would dose-dependently decrease MAC_SEVO.Study designRandomized crossover experimental study.AnimalsSix healthy, adult female mixed-breed dogs (24.2 ± 2.6 kg).MethodsEach dog was studied on two occasions with a 7-day washout period. Anesthesia was induced using sevoflurane delivered via a mask. Baseline MAC (MAC_B) was determined starting 45 minutes after tracheal intubation. A noxious stimulus (50 V, 50 Hz, 10 ms) was applied subcutaneously over the mid-humeral area. If purposeful movement occurred, the end-tidal sevoflurane was increased by 0.1%; otherwise, it was decreased by 0.1%, and the stimulus was re-applied after a 20-minute equilibration. After MAC_B determination, dogs randomly received a tramadol loading dose of either 1.5 mg kg^?1 followed by a continuous rate infusion (CRI) of 1.3 mg kg^?1 hour^?1 (T1) or 3 mg kg^?1 followed by a 2.6 mg kg^?1 hour^?1 CRI (T2). Post-treatment MAC determination (MAC_T) began 45 minutes after starting the CRI. Data were analyzed using a mixed model anova to determine the effect of treatment on percentage change in baseline MAC_SEVO (p < 0.05).ResultsThe MAC_B values were 1.80 ± 0.3 and 1.75 ± 0.2 for T1 and T2, respectively, and did not differ significantly. MAC_T decreased by 26 ± 8% for T1 and 36 ± 12% for T2. However, there was no statistically significant difference in the decrease between the two treatments.Conclusion and clinical relevanceTramadol significantly reduced MAC_SEVO but this was not dose dependent at the doses studied.     

Sero-prevalence and identification of <Emphasis Type="Italic">Ornithobacterium rhinotracheale</Emphasis> in broiler flocks in south-eastern Iran

Ornithobacterium rhinotracheale is a gram negative bacterial pathogen causing respiratory tract infections in poultry. Tracheal, lung and serum samples were obtained from 21 broiler flocks of 8 farms from a slaughterhouse located in south-eastern of Iran. Among 630 tracheal and lung samples from samples resulting from 315 chickens, 11 (3.5%) ORT isolates were identified using biochemical tests. The isolates originated from 9 (42.9%) flocks out of 4 farms. All of the isolates were recovered from tracheal swabs and showed an API 20NE identification biocode 0-2-2-0-0-0-4. Of the 420 serum samples examined by ELISA, 134 (31.9%) sera from 17 (81.0%) flocks were positive for ORT antibodies. These results indicate that ORT is present in most broiler flocks with respiratory disorders in southeast Iran.     

Neotyphodium endophytes trigger salt resistance in tall and meadow fescues

Infection with Neotyphodium spp. endophytes increases resistance to drought stress and soil mineral imbalances in tall fescue (Festuca arundinacea Schreb. = Lolium arundinaceum (Schreb.) S. J. Darbysh.) and meadow fescue (Festuca pratensis Huds. = Lolium pratense (Huds.) Darbysh.). We hypothesized that resistance of these grasses to salinity stress may also be attributed to endophyte infection. Two tall fescue genotypes, Fa75 and Fa83, and one meadow fescue genotype, Fp60, infected (E+) with their endophytic fungi, Neotyphodium coenophialum (Glenn, Bacon and Hanlin) and N. uncinatum (Glenn, Bacon and Hanlin), respectively, and their noninfected counterparts (E–) were cultured in nutrient solution at three salinity levels of 0, 85, and 170 mM NaCl. Except for genotype Fa75, E+ plants exhibited higher leaf survival rates than E– clones at a high salinity level (170 mM). Root dry matter was higher in E+ than in E– plants, but shoot dry matter was not affected by endophyte infection. This resulted in a lower shoot‐to‐root ratio in E+ plants (1.63) compared with E– plants (2.40). Sodium (Na⁺) and chloride (Cl^–) concentrations were greater in roots of E– than in E+ clones. In shoots, Na⁺ and Cl^– concentrations were not affected by the endophyte. In contrast, E+ plants accumulated more potassium (K⁺), which resulted in a greater K⁺ : Na⁺ ratio in shoots of E+ than in those of E– plants. Our results show that endophyte infection reduced Na⁺ and Cl^– concentrations in tall fescue and meadow fescue roots but increased K⁺ concentrations in the shoots. Based on these results, we conclude that endophyte‐infected grasses may thrive better in salinity‐stress environments.     

High performance fibers production process using Taguchi experimental design

In this research, results of an experimental interaction effect of operating parameters on tensile strength carbon fibers from a commercial PAN-based precursor are investigated. Ten parameters at two and four levels (L₃₂=2¹×4⁹) were investigated: stabilization temperature at first stage (STFIS), stabilization duration time at first stage (SDTFIS), stabilization temperature at second stage (STSS), stabilization duration time at second stage (SDTSS), stabilization temperature at third stage (STTS), stabilization duration time at third stage (SDTTS), stabilization temperature at fourth stage (STFOS), stabilization duration time at fourth stage (SDTFOS), carbonization temperature (CT), and carbonization duration time (CDT). In this study, Taguchi method was used initially to plan a minimum number of experiments. Statistical analysis, analysis of variance (ANOVA), was also employed to determine the relationship between experimental conditions and yield levels. ANOVA was applied to calculate sum of square, variance, ratio of factor variance to error variance and contribution percentage of each factor on response. The results show that increasing all of parameters improves tensile strength performance. The optimum levels of influential factors, determined for tensile strength are STFIS 200 °C, SDTFIS 120 min, STSS 225 °C, SDTSS 120 min, STTS 240 °C, SDTTS 120 min, STFOS 260 °C, SDTFOS 60 min, CT 1400 °C and CDT 10 min. The results showed that CT and ODTFIS are the most and the less effective factors on response, respectively.     

Estimation,interrelationships and repeatability of genetic variability parameters in spring safflower using multi-environment trial data

The present investigation was carried out to estimate the interrelationships and repeatabilities of various variability parameters, i.e., genotypic (σ²g) and phenotypic (σ²p) variances, genotypic (GCV) and phenotypic (PCV) coefficients of variation, broad-sense heritability (h_b²), genetic advance (GA), and genetic gain (GG), using data derived from a number of plant characters [seed yield (SY), days to heading (DH) and maturity (DM), plant height (PH), and thousand kernel weight (TKW)] of 17 spring safflower genotypes grown in 27 environments in Iran during 2003–2005. The analysis of variance for the five characters revealed significant differences among the genotypes in most of the environments, indicating a very high variability within the genotype. High genotypic and phenotypic variances in the quantitative traits, particularly for SY, were markers of increased success. A close correlation between GCV and PCV was observed for all the traits, indicating that all of the characters were less influenced by the environment and that the variability which exists in these characters is under genetic influence; however, the relatively higher values of PCV indicate the predominant role of environment. High expected genetic advances were observed for SY, but this trait showed large fluctuations in different environments (97.4%). High and low mean values of heritability were observed for DH (74.3%) and SY (59.7%), respectively, whereas high and low mean values of genetic gain were found for SY (60.3%) and DM (4.2%), respectively. High heritability coupled with low GA as a percentage of the mean was observed for DH and MD, whereas moderate heritability with moderate GA as a percentage of the mean was exhibited for SY. Analysis of correlation among the parameters showed that they were strongly and constantly correlated with each other, but none of them were consistently well correlated with the heritability parameter (h_b²). Based on estimates of the genetic variability parameters within each trial, the ranking of genotypes in the low-performance subset for all traits differed from that in the high-performance subset. This result indicates poor repeatability for the genetic variability parameters. The estimates of the parameters in the multi-year trials were almost constant and repeatable, whereas the responses over years showed poor repeatability.     

Changes in Sperm Production,Sperm Motility,and Composition of Seminal Fluid in Caspian Brown Trout,Salmo trutta caspius,Over the Course of a Spawning Season

This study was carried out to evaluate milt quality in male Caspian brown trout (Salmo trutta caspius) over the course of the winter spawning season. Milt samples were collected biweekly during December and January. Chemical composition of seminal fluid, sperm production (milt volume, sperm density, spermatocrit,) and sperm motility characteristics (percentage and duration of motility) were measured. Milt volume, sperm density, osmolality, seminal minerals (Ca²⁺, Mg²⁺, K⁺, Na⁺, Cl^?), and total protein gradually decreased over the spawning season. Glucose and triglyceride content of milt did not show significant changes over the spawning season. Milt pH and the percentage and duration of motility were comparatively stable, declining only at the end of the season. Significant positive correlations were found between sperm density and seminal minerals, total protein and spermatocrit; percentage of motile spermatozoa and seminal minerals, total protein; and duration of motility and K⁺, Cl^?, total protein, and pH. Results show that season has a significant influence on milt quality in male Caspian brown trout, with the best milt being available at the beginning of spawning season.     

Effects of the dietary protein levels and the protein to energy ratio in sub‐yearling Persian sturgeon,Acipenser persicus (Borodin)

A 3 × 4 factorial design was used to evaluate the dietary protein requirement and to determine the optimum dietary protein to energy (P/DE) ratio in sub‐yearling Persian sturgeon, Acipenser persicus, reared in the indoor system. Twelve experimental diets (₄₀P₁₆, ₄₀P₁₇, ₄₀P₁₈, ₄₀P₁₉, ₄₅P₁₉, ₄₅P₁₇, ₄₅P₁₈, ₄₅P₁₉, ₅₀P₁₆, ₅₀P₁₇, ₅₀P₁₈ and ₅₀P₁₉) were formulated and prepared to contain three protein levels (40%, 45% and 50%) and four digestible energy levels (16, 17, 18 and 19 kJ g^?1 diet) at each protein level. Fish averaging 103.3 ± 3.5 (mean ± SD) were fed one of the experimental diets for 14 weeks. At the end of the experimental period, there were significant energy effects (P < 0.05) on weight gain (WG) and specific growth rate (SGR). Weight gain and SGR tended to decrease, although non‐significantly, with increase in dietary protein levels. Furthermore, there were significant protein and energy interaction effects on WG, SGR, hepatosomatic index and protein efficiency ratio. However, there were no significant dietary protein, energy or their interaction effects on feed efficiency for fish fed all diets. Weight gain and SGR of fish fed ₄₀P₁₉ were significantly higher than those of fish fed ₄₀P₁₆, ₄₅P₁₆, ₄₅P₁₇, ₅₀P₁₆ and ₅₀P₁₇ diets (P < 0.05). There were no significant differences in WG and SGR among fish fed ₄₀P₁₇, ₄₀P₁₈, ₄₀P₁₉, ₄₅P₁₈, ₄₅P₁₉, ₅₀P₁₈ and ₅₀P₁₉ diets. These results may indicate that the optimum dietary protein requirement and the P/DE ratio could be 40% protein and 22.0 mg protein kJ^?1 (₄₀P₁₈), respectively, in Persian sturgeon, based on growth performance and feed utilization.     

Effects of replacing fish meal by soybean meal along with supplementing phosphorus and magnesium in diet on growth performance of Persian sturgeon, Acipenser persicus

Looking for replacing fish meal by cheaper and more sustainable protein sources is essential for reducing the cost of fish feeds. Soybean meal is a suitable alternative protein sources for carnivorous fish such as Persian sturgeon, Acipenser persicus. However, it contains antinutritional factors that may affect bioavailability of minerals and lead in reduced growth. Achieving a cost-effective diet that does not have negative effects on growth is the goal of aquaculture programs. A 10-week experiment was conducted with Persian sturgeon (352.07 ± 5.51 g) to determine the combined effects of phosphorous (SP), magnesium and phosphorous (SPMg), phytase (SF), phytase and magnesium (SFMg), phosphorous and phytase (SPF), phosphorous, magnesium and phytase (SPMgF) on weight gain, feed efficiency, specific growth rate, and condition factor. A control diet was prepared with fish meal as a control group. Inclusion of P, Mg, and phytase contents within soybean diets did not improve feed efficiency, and still, the control diet containing fish meal showed better weight gain and feed efficiency. Among soybean meal groups, feed efficiency and specific growth rate were significantly improved for fish fed the diet containing just phytase (SF) and both phytase and phosphorus (P ≤ 0.05). It was true for specific growth rate and condition factor. Phytase significantly enhanced growth whether included with or without phosphorous. This study showed that fish meal is more sufficient for Persian sturgeon, and soybean meal could be partly an alternative protein source if phosphorous supplied for fish by incorporation with microbial phytase or phosphorous.     

Modulating gut microbiota and digestive enzyme activities of Artemia urmiana by administration of different levels of Bacillus subtilis and Bacillus licheniformis

The aim of this study was to evaluate the effects of Bacillus subtilis and Bacillus licheniformis on growth, gut microbiota, and digestive enzyme activities of Artemia urmiana. Three diets containing 10² (T₁), 10⁴ (T₂), 10⁶ (T₃) CFU of probiotics/g feed, and a control diet (C) without probiotic were used through a completely randomized design (treatments with triplicates). Twelve plastic tanks with the capacity of 60- l and density of 20 nauplii/ml were used and the trial continued for 15?days. Results showed that probiotics significantly increased the total length of A. urmiana (P?<?0.05). Although the total aerobic gastrointestinal bacteria count showed no significant differences among the treatments, the total Bacillus count significantly increased in experiments (P?<?0.05). The ratio of TCBS to total aerobic bacteria count was significantly lower in T₁ (0.31?±?0.05), T2 (0.27?±?0.15), and T₃ (0.25?±?0.05) compared to the control (0.76?±?0.34) (P?<?0.05). The probiotics were able to increase the protease and amylase activities (P?<?0.05). No significant effect on lipase activity. The study determined T₂ and T₃ as the most effective treatments for improving growth, bacterial flora, and digestive enzyme activities. As less probiotic needed in T₂, using 10⁴ bacteria per g diet is recommended for rearing Artemia up to the maturity stage.