Influence d''infections préalables sur l''evolution de la pleuro-pneumonie porcine expérimentale chez des porcs exempts d''organismes pathogènes spécifiques.

This study was designed to determine in six-week old specific pathogen free pigs, the effect of previous experimental exposure to Mycoplasma hyopneumoniae and transmissible gastroenteritis virus on a challenge infection with Actinobacillus pleuropneumoniae. Pigs exposed simultaneously to M. hyopneumoniae and transmissible gastroenteritis virus appeared more resistant to challenge (one week later) with A. pleuropneumoniae. Four pigs out of a group of ten died following the challenge infection, compared to all ten pigs in the control group not submitted to previous infections. Clinical signs and lesions were also less severe in the previously infected group than in the control group. Pigs submitted to a single previous infection with M. hyopneumoniae only appeared to be less resistant to the challenge infection than pigs submitted to the dual previous infection with M. hyopneumoniae and the transmissible gastroenteritis virus. A correlation was found between the resistance of pigs to the challenge infection and their serum gammaglobulin levels.     

Carcase characteristics of a heavy Japanese quail line under introgression with the roux gene

1. The roux plumage sex-linked recessive gene may be used for early sexing of Japanese quail in crossbreeding production systems with wild-type and roux lines. However, associated effects of the gene on carcase and meat composition need to be assessed. 2. Quail carcases from pure Line K males and females (100% K), a heavy meat line which was used as the recipient line for the introgression of the roux gene, and from same-age roux or wild-type females from the second generation of introgression (75% K) were dissected. The effects of sex, line and plumage colour on carcase components and on protein and lipid contents of various tissues were estimated. 3. Expected sex differences in carcase weights were obtained, with marginally higher values for females. However, weights of parts and carcase yield (ratio of empty carcase weight without head, neck and feet over live body weight) were similar for both sexes in pure Line K which had a 68% carcase yield. Lipid contents in leg meat were higher in males (3.1%) than in females (2.7%). 4. The roux gene did not seem to have any major impact on carcase parts or composition. However, in roux birds, leg skin was marginally higher in lipids and pectoralis major lower in proteins than in wild-type ones.     

Pomological and Nutraceutical Properties in Apricot Fruit: Cultivation Systems and Cold Storage Fruit Management

We have investigated the effect of cultivation systems and fruit post-harvest management on the antioxidant properties of apricot fruits. Trees of five cultivars ‘Tyrinthos’, ‘Cafona’, ‘Bella d’Italia’, ‘Vitillo’ and ‘Pellecchiella’ were cultivated under integrated and organic systems. Fruits were collected at full maturity stage and analyzed either immediately or after storage at 4±0.5 °C and 85% of relative humidity for seven and 14 days. The main pomological traits (weight, colour, flesh firmness, total soluble sugars, titratable acidity) and antioxidant properties were analyzed. The total antioxidant capacity (TAC by TEAC method), total phenols content (TP by Folin-Ciocalteu method) and carotenoid content by HPLC-DAD were monitored. Cultivar characterization by principal component analysis (PCA) indicated a large variability on pomological and antioxidant properties of apricot fruits. ‘Bella d’Italia’ showed better TAC and TP values compared to the other cultivars. ANOVA interactions between cultivar and cultivation system (organic/integrated) were found for the antioxidant properties. These interactions may help to select a set of genotypes with better performances under organic system, which in our study might be indicated in ‘Cafona’ and ‘Bella d’Italia’.     

Drivers of adoption of eucalypt tree farming by smallholders in Thailand

Eucalypt (Eucalyptus spp.) tree farming is a source of income for many smallholders in developing and emerging countries and critical to the resource supply of many pulp and paper companies. These companies rely on smallholders adopting tree farming, sometimes by offering a contract. This paper reports a study from four regions of Thailand, where smallholder eucalypt tree farming is important, which investigated what characteristics of smallholders were associated with greater adoption of tree farming. A total of 461 eucalypt tree farmers and 171 non-tree farmers were randomly selected and surveyed in these regions, using a door-to-door household survey. A logit analysis corroborated hypotheses about the drivers of adoption. Qualitative analyses were used to inform interpretation of the quantitative results and shed light on the role of eucalypt tree farming in smallholders’ livelihood. Results demonstrate that those with suitable land available are more likely to adopt eucalypt tree farming than others. In addition, perception of land tenure security matters in the adoption of tree growing, but holding a formal land tenure document does not. Adoption of eucalypt tree farming in Thailand is not part of a land use intensification strategy. Instead, eucalypts are used as an alternative crop for low productivity land, on which eucalypts are the most profitable crop. Eucalypt tree farming also gives smallholders an opportunity to diversify their income. In addition, this alternative land use has the advantage of requiring low labour inputs between planting and harvest. This is particularly advantageous for many tree growers who have off-farm income or rely on hired labour for farming their land.     

Exposure Patterns and Long Term Sequelae on Adults and Children in Two Canadian Indigenous Communities Exposed to Methylmercury

Health Canada has been collecting data on Inuit and First Nations' methylmercury (MeHg) levels for 25 years. A national overview has been completed and more focussed analyses have now been initiated. This paper deals with two interdependent analytical components: 1) a longitudinal overview of the two most extensively sampled communities in Canada: Grassy Narrows and Whitedog, the residents of which were exposed to ‘point source’ mercury pollution in the 1970's; 2) fetal and post-natal exposure to mercury in these two communities including an outline of the First Nation MeHg child development pilot project in the two communities. A retrospective analysis of Grassy Narrows and Whitedog shows a decreasing MeHg trend in both communities. In Grassy Narrows the average individual annual peak methylmercury level in blood has decreased significantly, from 23.80 ppb (range 1.50–322.90) in 1976 to 7.5 ppb (1.7–46.7) in 1995 (r=-0.65, p<0.001). In Whitedog the average peak has also decreased significantly, from 12.87 ppb (1.50–172.00) in 1976 to 6.1 ppb (1.7–33.3) in 1995 (r=-0.59, p<0.005). However, behind these positive trends is the reality of two communities still suffering the effects of disrupted lifestyles and socio-cultural damage. A number of cord blood samples, maternal blood samples, and samples from women of child-bearing age from these communities have been in the “risk” group (according to the 1990 WHO guidelines). We are therefore now assessing the long term effects of fetal exposure in the communities. Standard clinical examinations in the past failed to prove abnormalities attributable to methylmercury but did not include subtle neuropsychological development tests. Many of the fetally exposed children are now in secondary school. Therefore, we have initiated a pilot project to assess long term effects of methylmercury exposure on the neuropsychological development of these children whose fetal exposure we know. The pilot child development project which was initiated in 1995 in Grassy Narrows and Whitedog, with community support, includes four main components: i) a school records review, looking at attendance, marks, and atypical behaviour; ii) teachers' questionnaires, targeting child behaviour; iii) an in-depth neuropsychological test battery focussing on subtle factors, such as memory, attention, executive functions, perceptual functions and sensory / motor development; and iv) hair sampling, providing current MeHg levels to correlate with results from the previous sampling and findings from the first three components. An overview of progress is given.     

Soluble sugars and carboxylic acids in ripe apricot fruit as parameters for distinguishing different cultivars

Major sugar and carboxylic acid components in apricot flesh fruits were detected and quantified. Fifty-one genotypes including clones growing in France, Spain, Italy, Greece and USA, belonging to the INRA germ plasm collection has been evaluated. Principal component analysis (PCA) has been performed to study correlation among fruit quality measurements and to interpret relationships between genotypes as a tool for germ plasm characterization. A marked variation in malic and citric acid content has been observed and PCA revealed clusters of apricot genotypes for the malic/citric ratio content. A good correlation between sugar component and refractometer index (r = 0.83) has been detected. The wide range of diversity in malic and citric acid content in apricot germ plasm makes it possible to breed and select genotypes with improved flavour on the basis of superior phenotypes. This revised version was published online in July 2006 with corrections to the Cover Date.     

Hemagglutinating activity associated with bovine herpesvirus type 1

Using C57BL/HPB mouse erythrocytes, hemagglutination has been observed with the Los Angeles and Colorado-1 strains of bovine herpesvirus type 1 and with 12 other Canadian field isolates as well. The specificity of the hemagglutination observed with the viral strains has been confirmed by a hemagglutination-inhibition assay.