Experimental in vitro transmission of Babesia sp. (EU1) by Ixodes ricinus

Babesia sp. (EU1), first characterized in 2003, has been implicated in human cases of babesiosis in Italy, Austria and Germany. It has been identified in roe deer and in its suspected tick vector, Ixodes ricinus, in several European countries. The aim of the present study was to validate the competence of I. ricinus as a vector of Babesia sp. (EU1) via experimental infections. For this purpose, a parasite strain isolated from roe deer was cloned in sheep erythrocytes. After experimental infections, parasite DNA was successfully amplified by PCR in both eggs and larvae originating from infected I. ricinus females and in the salivary glands of females exposed to Babesia sp. (EU1) as nymphs. We also demonstrate that infected females were able to transmit parasite DNA during a new blood meal. Together with previous epidemiological studies, these results validate I. ricinus as a competent vector for Babesia sp. (EU1).     

A preliminary study on the suitability of Cervidil to induce cervical dilation for artificial insemination in ewes

The aim of this study was to evaluate the efficacy of Cervidil^®, a prostaglandin E₂ (PgE₂)-releasing vaginal insert used for induction of cervical ripening and labour in women, to enhance the ease of transcervical artificial insemination (TCAI) in anestrous ewes (June). It was hypothesized that the use of Cervidil^® prior to AI would cause dilation of the cervix, and thus alleviate the difficulty associated with traversing the cervix for semen deposition in sheep. Cervidil^® was inserted 12 h before insemination in six Rideau-Arcott ewes; six ewes served as untreated controls.Semen was deposited into the uterus of all six treated ewes but TCAI was possible only in four of the six control ewes. It can be concluded that Cervidil^® facilitated transcervical semen deposition in anestrous ewes. The treatment with Cervidil^® has the promise of a technique to improve transcervical AI and to enable non-invasive embryo transfer procedures in sheep.     

Ecology of termites from the genus <Emphasis Type="Italic">Nasutitermes</Emphasis> (Termitidae: Nasutitermitinae) and potential for science-based development of sustainable pest management programs

The genus Nasutitermes is among the most abundant wood-feeding Termitidae and an extremely diverse and heterogeneous group in terms of its biogeography and morphology. Despite the major role of several Nasutitermes species as structural pests, the phylogenetic status of this genus is still unclear, along with a confused taxonomy and species identification remaining difficult. The first aim of this review was thus to gather and discuss studies concerning the taxonomic status of the genus Nasutitermes in order to clarify this crucial point. Then, our goal was to gain new insights into the management of N. corniger, considered to be the most economically detrimental pest of this genus in South America and a Nasutitermes model species, while filtering available information concerning its biology through the prism of termite control, as well as critically examine the existing methods. We indeed strongly believe that increasing our knowledge of this species’ biological strategies is the key to progress in the challenging question of their sustainable management.     

Why are wheat yields stagnating in Europe? A comprehensive data analysis for France

The last two decades are witnessing a decline in the growth trend of cereal yields in many European countries. The present study analyses yield trends in France using various sources of data: national and regional statistics, scattered trials, results of agroclimatic models using climatic data. Effects in genetic changes through breeding, agronomy and climate are investigated as possible causes. Our results show that genetic progress has not declined but it was partly counteracted, from 1990 on, by climate change which in general is unfavorable to cereal yields in temperate climates because of heat stress during grain filling and drought during stem elongation. We cannot however, from the decade beginning in 2000, rule out agronomic causes, related to policy and economy, in particular the decline of legumes in the cereal rotations, replaced by oilseed rape and to a lesser extent the decrease in nitrogen fertilization.     

Diuron mineralisation in a Mediterranean vineyard soil: impact of moisture content and temperature

BACKGROUND: The diuron‐mineralising ability of the microbiota of a Mediterranean vineyard soil exposed each year to this herbicide was measured. The impact of soil moisture and temperature on this microbial activity was assessed. RESULTS: The soil microbiota was shown to mineralise diuron. This mineralising activity was positively correlated with soil moisture content, being negligible at 5% and more than 30% at 20% soil moisture content. According to a double Gaussian model applied to fit the dataset, the optimum temperature/soil moisture conditions were 27.9 °C/19.3% for maximum mineralisation rate and 21.9 °C/18.3% for maximum percentage mineralisation. The impact of temperature and soil moisture content variations on diuron mineralisation was estimated. A simulated drought period had a suppressive effect on subsequent diuron mineralisation. This drought effect was more marked when higher temperatures were used to dry (40 °C versus 28 °C) or incubate (28 °C versus 20 °C) the soil. The diuron kinetic parameters measured after drought conditions were no longer in accordance with those estimated by the Gaussian model. CONCLUSION: Although soil microbiota can adapt to diuron mineralisation, its activity is strongly dependent on climatic conditions. It suggests that diuron is not rapidly degraded under Mediterranean climate, and that arable Mediterranean soils are likely to accumulate diuron residues. Copyright © 2010 Society of Chemical Industry     

Bacillary angiomatosis in an immunosuppressed dog

A dog being treated with immunosuppressive doses of prednisone and azathioprine for pancytopenia of unknown origin, developed, over a 2‐week period, multiple erythematous nodular lesions in the skin including footpads. Skin samples revealed lesions identical to those of human bacillary angiomatosis (BA). The nodules were composed of multifocal proliferations of capillaries, each lined by protuberant endothelial cells. The capillary clusters were separated by an oedematous connective tissue, lightly infiltrated with degenerate inflammatory cells, including neutrophils and macrophages. Tissue sections stained with Warthin–Starry silver stain revealed large numbers of positively stained bacilli in the stromal tissue, most heavily concentrated around the proliferating capillaries. Lesions of vascular degeneration and inflammation were evident. Bartonella vinsonii subsp. berkhoffii genotype 1 was independently amplified and sequenced from the blood and the skin tissue. The pathognomonic nature of the histological lesions, demonstration of compatible silver‐stained bacilli in the tissue, and identification of B. vinsonii subsp. berkhoffii in the blood and tissue indicates that this is most likely the aetiologic agent responsible for the lesions. Antibiotic therapy was successful in resolving the nodules. It would appear that B. vinsonii subsp berkhoffii, like Bartonella henselae and Bartonella quintana, has the rare ability to induce angioproliferative lesions, most likely in association with immunosuppression. The demonstration of lesions identical to those of human BA in this dog is further evidence that the full range of clinical manifestations of human Bartonella infection occurs also in canines.     

Osteoma of the oral and maxillofacial regions in cats: 7 cases (1999-2009)

Objective-To describe clinical features of oral and maxillofacial osteomas in cats. Design-Retrospective case series. Animals-7 cats with oral or maxillofacial osteoma or both. Procedures-Medical records were reviewed for information on signalment, history, clinical signs, physical examination findings, diagnostic imaging findings, results of serum biochemical analyses and histologic testing, surgical procedures performed, and perioperative complications. Outcome was determined on the basis of follow-up telephone interviews of owners. Results-Cats ranged from 1 to 23 years of age. Clinical signs were observed in 5 cats and were attributed to the presence of the mass. Diagnostic imaging (radiography and computed tomography) and histologic examination confirmed the diagnosis of osteoma. Three cats were euthanatized; 1 cat was treated by mandibulectomy, 1 was treated by maxillectomy, and 2 were treated by debulking. At the time of follow-up at least 1 year after surgery, all 4 treated cats were alive, with owners reporting an acceptable quality of life. Conclusions and Clinical Relevance-Osteoma of the oral and maxillofacial regions is an uncommon tumor in cats. Most cats are examined during an advanced stage of the disease, when treatment options may be limited. Although osteoma is a benign tumor, the recommendation is to perform a clinical evaluation, diagnostic imaging, biopsy, and treatment early in the disease process, when less invasive surgical approaches may be feasible.     

Isoproturon mineralization in an agricultural soil

The impact of soil moisture content and temperature on isoproturon (3-(4-isopropylphenyl)-1,1-dimethyl-urea [IPU]) mineralization activity was assessed on an agricultural soil regularly exposed to this herbicide. Mineralization of ¹⁴C-IPU was monitored on soil microcosms incubated at different temperatures (10°C, 20°C, 28°C) and soil moisture contents (9%, 12%, 15, 18%, 21%, 24%). An increase in temperature and/or soil moisture significantly enhanced the maximum rate and percentage of IPU mineralization while it decreased the lag time before mineralization. The maximum rate and percentage of IPU mineralization respectively ranged from 0.18% day⁻¹ and 9% for the lowest temperature and soil moisture content pair (10°C–9%) to 1.51% day⁻¹ and 27.1% for the highest pair (28°C–24%). Statistics revealed a cross interaction of temperature and soil moisture content on the maximum rate of IPU mineralization. The optimum conditions for IPU mineralization, estimated from the double Gaussian model, were 25.8°C and 24% soil moisture content. The influence of fluctuations in soil moisture content on IPU-mineralization was investigated by subjecting the soil microcosms to drought stress. When IPU was added at the end of the drought stress, it had no statistical effect on IPU mineralization. However, when it was added before the drought stress, two mineralization phases were observed: (1) one corresponding to the drought stress for which mineralization was low and (2) another one observed after restoration of soil moisture content characterized by higher mineralization rate. It can be concluded that climatic fluctuations affect the activity of IPU mineralizing microbial community, and may lead to an increase in IPU persistence.