RAPD Characterization of Single Females of the Root-knot Nematodes, Meloidogyne Spp.

Random amplified polymorphic DNA fingerprinting was performed on single females of root-knot nematodes, Meloidogyne spp., using a new procedure for DNA isolation. One-fourth of the total DNA amount isolated from a single female proved to be sufficient as a template in a polymerase chain reaction. Electrophoretic patterns of the amplified fragments were reproducible between replicates from a single female or sister females from the same progeny, and identical to those obtained with genomic DNA purified from a large number of nematodes. Moreover, a comparative analysis over three successive generations showed stability of the amplification patterns, thus demonstrating the utility of this procedure for epidemiological and ecological studies on root-knot nematodes.     

A retrospective study of 30 cases of frozen lamellar corneal graft in dogs and cats

Frozen lamellar corneal grafts and nictitating membrane flaps were used in 18 dogs and 12 cats to repair deep corneal defects. In all dogs either melting corneal ulcers or descemetoceles were present. In the 12 cats, nine had either a melting corneal ulcer or descemetocele, two animals had acute bullous keratopathy, and one cat had corneal sequestrum. Initial vascularization with gradual clearing of the graft occurred during the first 45 days postoperatively. At 60 days postoperatively, all eyes were visual. Frequent postoperative complications included: focal dehiscence of the wound ( n  = 9); melting of part of the graft ( n  = 7); and pigmentation of the graft ( n  = 4). The frozen lamellar corneal graft was a very safe technique, and restored the tectonic and the optical function of the cornea. It provided the best results in corneas with nonperforating corneal defects. This technique provides poorer results when the cornea was perforated prior to surgery or during the surgical procedure.     

Characterization of the Exoglucanase-Encoding Gene PaEXG2 and Study of Its Role in the Biocontrol Activity of Pichia anomala Strain K

ABSTRACT The PaEXG2 gene, encoding an exo-beta-1,3-glucanase, was isolated from the biocontrol agent Pichia anomala strain K. PaEXG2 has the capacity for coding an acidic protein of 427 amino acids with a predicted molecular weight of 45.7 kDa, a calculated pI of 4.7, and one potential N-glycosylation site. PaEXG2 was disrupted by the insertion of the URA3 marker gene, encoding orotidine monophosphate decarboxylase in strain KU1, a uracil auxotroph derived from strain K. Strain KU1 showed inferior biocontrol activity and colonization of wounds on apples, compared to the prototrophic strain. Antagonism and colonization were recovered after the restoration of prototrophy by transformation with the URA3 gene. Integrative transformation was shown to be mostly ectopic in strain K descendants (only 4% of integration by homologous recombination). PaEXG2 disruption abolished all detectable extracellular exo-beta-1,3-glucanase activity in vitro and in situ but did not affect biocontrol of Botrytis cinerea on wounded apples.     

Use of the distomedial-proximolateral oblique radiographic view of the elbow joint for examination of the medial coronoid process in dogs

OBJECTIVE: To describe and evaluate a new radiographic view of the elbow joint in dogs that would potentially enhance observation of the medial coronoid process (MCP). SAMPLE POPULATION: 20 cadaver limbs from 10 dogs and clinical examination of 100 elbow joints of 53 dogs. PROCEDURE: Twenty elbow joints from 10 cadavers were imaged by use of mediolateral, flexed mediolateral, craniocaudal, craniolateral-caudomedial oblique (Cr15L-CdMO), and distomedial-proximolateral oblique (Di35M-PrLO) radiographic views before and after placement of 3 lead pellets placed on the cranial, medial, and craniodistal aspect of the MCP. Three examiners independently reviewed these radiographs. One hundred elbow joints of 53 dogs with forelimb lameness and signs of pain elicited on palpation of the elbow joint were examined. These joints were radiographed and treated by use of arthroscopy. Three examiners independently graded the radiographs. RESULTS: The MCP was identified on all Di35M-PrLO views made during the anatomic study. The Di35M-PrLO view had the largest area under the receiving operating characteristic (ROC) curve for detection of abnormalities of the MCP. Fractured and nonfractured MCP could only be significantly differentiated on Di35M-PrLO and mediolateral views. The Di35M-PrLO view had a higher agreement between examiners than other radiographic views for detection of fractures of the MCP. CONCLUSION AND CLINICAL RELEVANCE: The Di35M-PrLO view enhances the identification of anomalies and fragmentation of the MCP in dogs, compared with other radiographic views. The Di35M-PrLO view may be of benefit for early screening of dogs potentially affected with elbow dysplasia.     

Three-dimensional kinematics of the equine interphalangeal joints: articular impact of asymmetric bearing

The objective of this study was to assess the effects of asymmetric placement of the foot on the three-dimensional motions of the interphalangeal joints. Four isolated forelimbs were used. Trihedrons, made of three axes fitted with reflective markers, were screwed into each phalanx. They allowed to establish a local frame associated with each bone and thus to define the spatial orientation of the phalanges. The limbs were then placed under a power press, and subjected to compression with gradually increasing force (from 500 to 6 000 N). The procedure was performed in neutral position and with the lateral or medial part of the foot raised by a 12 degrees wedge. Flexion, collateromotion (passive abduction/adduction) and axial rotation of the interphalangeal joints were measured using a cardan angle decomposition according to the principle of the "Joint Coordinate System" described by Grood and Suntay. Raising the lateral or medial part of the hoof induced collateromotion (about 5.6 degrees +/- 0.8) and axial rotation (about 6.5 degrees +/- 0.5) of the distal interphalangeal joint. The proximal interphalangeal joint underwent axial rotation (about 4.7 degrees +/- 0.5 at 6 000 N) and slight collateromotion. Both interphalangeal joints underwent collateromotion in the direction of the raised part of the foot (i.e., narrowing of the articular space on the side of the wedge), whereas axial rotation occurred in the direction opposite to the raised part of the foot. These results confirm the functional importance of interphalangeal joint movements outside the sagittal plane. In particular they demonstrate the involvement of the proximal interphalangeal joint in the digital balance. These data are helpful for the identification of biomechanical factors that may predispose to interphalangeal joint injury. Also the data may be of use for the rational decision making with respect to exercise management and corrective shoeing of the lame horse.     

Towards a lower prevalence of Oestrus ovis infections in sheep in a temperate climate (south west France)

Oestrus ovis larvae are obligatory parasites of the nasal and sinus cavities of sheep and goats. In the temperate climate of western Europe, fly attacks occur between May and October and the first stage larvae arrest their development within the host between October and February. Oestrosis clinical signs such as nasal discharge and sneezing are well known by sheep breeders in southwest France. According to veterinarian recommendations, most of them treat their animals with long lasting fasciolicides once a year at least, mainly during the fly activity period and at the beginning of the hypobiotic period (when the parasitic population is only constituted of larvae). The consequences of these therapeutic programs were analysed in a local slaughterhouse by larval counts. Both prevalence and intensities of O. ovis infections decreased between 1989-1991 (before the use of systematic treatments) and 1996-1998 (after the spread of these treatments). The use of systematic treatments during the fly activity period and the beginning of the hypobiotic period seems to be very efficient in O. ovis control and could theoretically lead to a possible 'eradication' program as with cattle hypodermosis. Nevertheless the presence of parasites in apparently healthy goats, the possibility for a fly generation to develop before the first treatment in July-August and the succession of several fly generations all around the year in southern Mediterranean and tropical countries will maintain O. ovis infections. Furthermore, there are increased concerns about drug residues on consumer health and environment and this is the basis for the prospect of alternative strategies in O. ovis control.     

GIS Coop: networks of silvicultural trials for supporting forest management under changing environment

Key message

The diversity of forest management systems and the contrasted competition level treatments applied make the experimental networks of the GIS Coop, a nationwide testing program in the field of emerging forestry topics within the framework of the ongoing global changes.

Context

To understand the dynamics of forest management systems and build adapted growth models for new forestry practices, long-term experiment networks remain more crucial than ever.

Aims

Two principles are at the basis of the experimental design of the networks of the Scientific Interest Group Cooperative for data on forest tree and stand growth (GIS Coop): contrasted and extreme silvicultural treatments in diverse pedoclimatic contexts.

Methods

Various forest management systems are under study: regular and even-aged stands of Douglas fir, sessile and pedunculate oaks, Maritime and Laricio pines, mixed stands of sessile oak, European silver fir, and Douglas fir combined with other species. Highly contrasted stand density regimes, from open growth to self-thinning, are formalized quantitatively.

Results

One hundred and eighty-five sites representing a total of 1206 plots have been set up in the last 20 years, where trees are measured regularly (every 3 to 10 years). The major outputs of these networks for research and management are the calibration/validation of growth and yield models and the drawing up of forest management guides.

Conclusion

The GIS Coop adapts its networks so that they can contribute to develop growth models that explicitly integrate pedoclimatic factors and thus also contribute to research on the sustainability of ecosystems under environmental and socio-economic changes.