Investigating Soil Factors Responsible for the Problematic Growth Of 51 Olive (Olea Europαea L.) Cultivars in an Alluvial Soil of Northern Greece

Fifty-one (51) olive cultivars (six trees per cultivar) were planted in an alluvial soil of an experimental field in Northern Greece for study of their growth. Soil is sandy loam (SL) - loamy sand (LS), moderately alkaline and presents no salinity or alkalinity. Despite the applied agronomic practices, i.e., soil fertilization, irrigation, and pest control, about half of the trees did not respond positively to the field conditions, while the remaining ones showed low to moderate growth based on measurements of height and crown diameter. Soil and leaf tissues analysis as well as penetration resistance (PR) measurements showed that olive trees' growth problems could be attributed to a combination of high PR values (>3 MPa) and to a certain degree to low fertility (especially nitrogen and potassium deficiencies). Under the prevailing soil conditions, the most resistant olive cultivars proved to be Dafnolia, Maronia, Oblonca, Ascolana, and Frantoio.     

In vivo and in vitro efficacy of sainfoin (Onobrychis viciifolia) against Eimeria spp in lambs

The effect of sainfoin (Onobrychis viciifolia) against ovine coccidia was evaluated in vivo and in vitro. In 3 in vivo trials weaned lambs were allocated into two treatment groups receiving diets with either lucerne (Medicago sativa) or sainfoin. During the trials, which lasted for 7 (trial 1) or 8 weeks (trials 2 and 3), oocysts per gram of faeces (OPGs), faecal scores and weight gain were recorded. In two of the experiments (trials 1 and 3) a reduction in the mean oocyst excretion rates was observed, starting three to four weeks after sainfoin hay feeding. This reduction ranged between 21.3% (trial 1) and 61.7% (trial 3) compared to the control values. As a result, a decrease in the total number of oocysts excreted (expressed as the mean area under the curve of the OPG) was observed from week 4 to the end of the two trials, respectively (trial 1: 42.6% reduction, p=0.05; trial 3: 52.4% reduction, p=0.06). The results did not show any significant diet effect on lamb growth rates and faecal scores. In the in vitro experiments the effect of 39 sainfoin extracts were tested in an oocyst sporulation inhibition assay. The Eimeria oocysts sporulation inhibition throughout the experiments did not exceed 10.7%, showing that extracts of this forages do not have a significant inhibitory effect on Eimeria oocyst sporulation. This was an initial attempt to investigate a possible anticoccidial effect of sainfoin and further studies are needed in order to better understand its mode of action against Eimeria.     

Effects of long-term dietary supplementation with clinoptilolite on incidence of parturient paresis and serum concentrations of total calcium, phosphate, magnesium, potassium, and sodium in dairy cows

OBJECTIVE: To determine whether dietary supplementation with clinoptilolite affects the incidence of parturient paresis and serum concentrations of total calcium (tCa), inorganic phosphorus (PO(4) (2)), magnesium (Mg2+), potassium (K+), and sodium (Na+) in dairy cattle. ANIMALS: 52 dairy cows. Procedure-Cows were placed into 3 groups. The first 2 groups (group A [n = 17] and group B [17]) were offered a concentrate supplemented with 1.25% and 2.5% clinoptilolite, respectively. The third (group C [n = 18]) served as a control and was offered the concentrate alone. The experiment started 1 month before parturition and lasted until the beginning of the next nonlactating period. Around the time of calving, all cows were monitored for the development of parturient paresis. Blood samples were taken at the commencement of the experiment, on the day of calving, and thereafter at monthly intervals to measure serum tCa, PO(4) (2), Mg2+, K+, and Na+ concentrations. Results-The incidence of parturient paresis in group B cows was significantly lower, compared with group C cows. However, serum concentrations of tCa, P(O4) (2), Mg2+, K+, and Na+ were not significantly affected by long-term supplementation with clinoptilolite. CONCLUSIONS AND CLINICAL RELEVANCE: In the context of this experiment, clinoptilolite supplementation at 2.5% appeared to have reduced the incidence of parturient paresis in dairy cows, suggesting that its effectiveness depends on the amount incorporated in the ration of cows. Addition of clinoptilolite in the concentrate of dairy cows during the nonlactating period could be used as a cost-effective preventive treatment for parturient paresis.     

Cytologic patterns of lymphadenopathy in dogs infected with Leishmania infantum

BACKGROUND: Lymphadenopathy in canine leishmaniosis has been reported as reactive lymphoid hyperplasia or granulomatous (histiocytic) lymphadenitis. However, we are unaware of information on the effect of latent Leishmania infection on lymph node cytology compared with clinically affected dogs. OBJECTIVES: The aim of the present study was to investigate cytologic patterns of lymphadenopathy in dogs with clinical and subclinical forms of leishmaniosis and to correlate cytologic findings with the density of Leishmania amastigotes in fine needle aspiration (FNA) smears. METHODS: FNA cytology of prescapular or popliteal lymph nodes was evaluated on 32 dogs with clinical evidence of leishmaniosis (group A), 24 subclinically infected dogs (group B), and 17 clinically healthy noninfected dogs (group C); groups were based on the results of serologic and PCR tests for Leishmania sp. Differential nucleated cell counts (based on 300 cells) and amastigote density were determined microscopically. Cytologic findings were categorized and compared among groups. RESULTS: Cytologic abnormalities were found in 19 of 32 (59.4%) dogs in group A, 1 of 24 (4.2%) dogs in group B, and 2 of 17 (11.8%) dogs in group C and were significantly more frequent in group A than group B (P <.001) or C (P = .001). In group A, 68.7% of the dogs had lymphoid hyperplasia, 12.5% had lymphoid hyperplasia and histiocytic lymphadenitis, 6.3% had histiocytic lymphadenitis, and 3.1% had lymphoid hyperplasia and neutrophilic lymphadenitis. Lymphoid hyperplasia was also noted in 1 dog in group B, and lymphoid hyperplasia and eosinophilic lymphadenitis were each found in 1 dog in group C. Lymph node smears from 31 (96.9%) dogs in group A and 6 (25%) dogs in group B were positive for Leishmania amastigotes; however, no correlation was found between the density of amastigotes and cytopathologic patterns of lymphadenopathy. CONCLUSION: Abnormal lymph node cytology is much more common in dogs with clinical leishmaniosis than in dogs with subclinical infection, and primarily involves lymphoid hyperplasia. Despite finding no association between the density of amastigotes and type of lymphadenopathy, lymph node cytology still is a valuable diagnostic tool for diagnosing canine leishmaniosis.     

Effect of sulfite-hydrosulfite and nitrite on thiol redox state, oxidative stress and sclerotial differentiation of filamentous phytopathogenic fungi

This study shows that Na₂S₂O₄, Na₂SO₃ and NaNO₂ decreased differentiation of filamentous phytopathogenic fungi representing the four main types of sclerotia at maximum growth non-inhibiting concentrations, and also increased and decreased the oxidized and the reduced components of their thiol redox state, respectively. Na₂S₂O₄, Na₂SO₃ and NaNO₂ also severely inhibited fungal growth at certain concentrations. These effects concurred by the increase of the high oxidative stress indicator lipid peroxidation and could be attributed to the oxidative cytotoxicity of sulfites and nitrite. The cytotoxic mechanism of the latter may be related to the acidic pH. Sulfites and nitrite can be used as potent fungicides against sclerotiogenic phytopathogenic fungi by acting as growth inhibiting cytotoxic oxidants and by sustaining fungi in their undifferentiated hyphal stage, in which they are more vulnerable to degradation by soil microorganisms.     

The Efficiency by Which Thrips tabaci Populations Transmit Tomato spotted wilt virus Depends on Their Host Preference and Reproductive Strategy

ABSTRACT Arrhenotokous and thelytokous populations of Thrips tabaci from tobacco or leek plants were evaluated for their ability to transmit Tomato spotted wilt virus (TSWV) and for their host preference. Transmission efficiencies were comparatively studied using leaf disks of Petunia hybrida, Datura stramonium, and Nicotiana tabacum cv. Basmas. Adults of arrhenotokous populations collected on infected tobacco plants in the field were efficient transmitters (up to 48.5% transmission) and remained so when maintained on tobacco for several generations. Arrhenotokous T. tabacipopulations from leek plants were poor transmitters (up to 3.1% transmission), whereas no transmission was obtained with thelytokous populations from leek. All populations could infest leek, however none of the arrhenotokous and thelytokous populations from leek plants was able to infest tobacco. TSWV could be acquired by both first and second larval instars of a T. tabacipopulation from tobacco. However, the transmission by adults decreased with the age at which the virus was acquired by larvae. The highest efficiencies (61% of males and 51% of females transmitted) were obtained when newborn (0- to 24-h old) larvae acquired the virus. The majority of thrips started to transmit after becoming adult and rates were positively correlated with the temperature at which the thrips were kept. The median latent period values found for adults decreased with increasing temperature. The median acquisition access period (AAP50) of the population was 41 min, whereas the AAP(50) was 65 min for males and 35 min for females. The median inoculation access period of males was 246 and 365 min on tobacco and petunia, respectively, and 96 and 345 min for females. The results show that T. tabaci forms a complex in terms of host preference, reproductive strategy, and ability to transmit TSWV. The transmission parameters show that the thrips of arrhenotokous populations infesting tobacco are highly efficient vectors.     

Efficacy of temozolomide or dacarbazine in combination with an anthracycline for rescue chemotherapy in dogs with lymphoma

OBJECTIVE: To compare results of treatment with temozolomide or dacarbazine, in combination with an anthracycline, in dogs with relapsed or refractory lymphoma. DESIGN: Nonrandomized, controlled clinical trial. ANIMALS: 63 dogs with relapsed or refractory lymphoma. PROCEDURES: Chemotherapy was administered in 21-day cycles. A combination of temozolomide and an anthracycline (doxorubicin or dactinomycin) was administered to 21 dogs and a combination of dacarbazine and an anthracycline was administered to 42 dogs. Efficacy and toxicoses were assessed. Results-Thirteen of the 18 (72%) dogs treated with the temozolomide-anthracycline combination and 25 of the 35 (71%) dogs treated with the dacarbazine-anthracycline combination had a complete or partial response. Median duration of response to rescue chemotherapy was 40 days (range, 0 to 217 days) for dogs in the temozolomide group and 50 days (range, 0 to 587 days) for dogs in the dacarbazine group. The incidence of high-grade hematologic toxicoses was significantly higher among dogs in the dacarbazine group than among dogs in the temozolomide group, but the incidence of gastrointestinal tract toxicoses was not significantly different between groups. There were no significant differences between groups in regard to proportion of dogs with a complete or partial response, duration of response to rescue chemotherapy, survival time following rescue chemotherapy, or overall survival time. CONCLUSIONS AND CLINICAL RELEVANCE: Both combinations had promise in the treatment of dogs with relapsed or refractory lymphoma, although administration of temozolomide was more convenient than administration of dacarbazine and caused fewer hematologic toxicoses.     

Social network analysis of sheep grazing different plant functional groups

Social Network Analysis (SNA) is used for the first time to investigate the relations between plant functional groups and social structure of grazing sheep. The research was conducted on a grassland in Crete's island Lefka Ori, Greece during 2016. A flock of 20 sheep of Sfakion race was analysed as a network and the sheep as nodes. The focal sampling technique was applied during four experimental periods of four consecutive days × eight hours/day. The plant species selected by sheep during grazing were categorized into four functional groups (grasses, broad‐leaved forbs, shrubs and trees), and the proximity and conflict relations that were developed among the flock members were recorded. The tools of SNA were defined and interpreted in the sheep flock, and the Visone software is used to calculate the network variables of proximity and conflicts relations of nodes. Correlations between the plant functional groups and network variables were examined by Spearman's bivariate correlation test. Sheep collectivity was enhanced while grazing grasses and simultaneously, a tendency for hierarchization within the flock was identified. Similarly, the proximity of sheep increased during forbs’ grazing while their individualism was strengthened. When grazing shrubs, the proximity of sheep was only in part maintained while the grazing of trees seems as the most deconstructive forage option of sheep proximity relations. In general, the grazing of all plant functional groups decreases conflicts among sheep except that of trees, which was insignificant for developing such relations.     

Degradation and adsorption of terbuthylazine and chlorpyrifos in biobed biomixtures from composted cotton crop residues

BACKGROUND: Biobeds have been well studied in northern Europe, whereas little is known regarding their use in southern Europe. The degradation and adsorption of terbuthylazine (TA) and chlorpyrifos (CP) were studied in three different biomixtures composed of composted cotton crop residues, soil and straw in various proportions, and also in sterilised and non‐sterilised soil. RESULTS: Compost biomixtures degraded the less hydrophobic TA at a faster rate than soil, while the opposite was evident for the more hydrophobic CP. These results were attributed to the rapid abiotic hydrolysis of CP in the alkaline soil (pH 8.5) compared with the lower pH of the compost (6.6), but also to the increasing adsorption (K_d = 746 mL g^?1) and reduced bioavailability of CP in the biomixtures compared with soil (K_d = 17 mL g^?1), as verified by the adsorption studies. CONCLUSIONS: Compost had a dual but contrasting effect on degradation that depended on the chemical nature of the pesticide studied: a positive effect towards TA owing to increasing biodegradation and a negative effect towards CP owing to increasing adsorption. Overall, composted cotton crop residues could be potentially used in local biobed systems in Greece, as they promoted the degradation of hydrophilic pesticides and the adsorption of hydrophobic pesticides. Copyright © 2010 Society of Chemical Industry