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1.
Context
Sustained timber harvesting conflicts with the long-term viability of boreal caribou (Rangifer tarandus caribou) populations. The spatial arrangement of harvest blocks in the landscape could mitigate the impact of logging on caribou populations. For the forest industry, however, these measures represent constraints that reduce the annual allowable cut (AAC).Objective
Estimate the long-term impacts of spatial constraints to harvesting, applied alone or in combination, on AAC and boreal caribou populations.Methods
We divided a 30,000 km2 region into 20 harvest block sizes varying from 50 to 1000 km2, and modeled the implementation of spatially explicit harvest schedule plans in combination with wildfire and caribou population dynamics. We then evaluated the probability of persistence of boreal caribou populations.Results
The probability of maintaining an AAC target declined with increasing target AAC, increasing size of operating area, and increasing adjacency constraints. In contrast, the probability of maintaining caribou populations declined with increasing AAC, decreasing size of operating areas, and decreasing adjacency constraints. An increase in operating area size from 50 to 300 km2 produced a considerable gain in AAC for all adjacency constraints.Conclusions
Because adjacency constraints led only to a small increase in the probability of maintaining caribou populations, we recommend adopting less constraining landscape management actions, such as a 70-year period between two consecutive harvests in the same ~300-km2 operating area.2.
Guillaume Delfau-Bonnet Nabila Imatoukene Tiphaine Clment Michel Lopez Florent Allais Anne-Lise Hantson 《Marine drugs》2022,20(4)
Projections show that the cultivation of microalgae will extend to the production of bio-based compounds, such as biofuels, cosmetics, and medicines. This will generate co-products or residues that will need to be valorized to reduce the environmental impact and the cost of the process. This study explored the ability of lipid-extracted Chlorella vulgaris residue as a sole carbon and nitrogen source for growing oleaginous yeasts without any pretreatment. Both wild-type Yarrowia lipolytica W29 and mutant JMY3501 (which was designed to accumulate more lipids without their remobilization or degradation) showed a similar growth rate of 0.28 h−1 at different pH levels (3.5, 5.5, and 7.5). However, the W29 cell growth had the best cell number on microalgal residue at a pH of 7.5, while three times fewer cells were produced at all pH levels when JMY3501 was grown on microalgal residue. The JMY3501 growth curves were similar at pH 3.5, 5.5, and 7.5, while the fatty-acid composition differed significantly, with an accumulation of α-linolenic acid on microalgal residue at a pH of 7.5. Our results demonstrate the potential valorization of Chlorella vulgaris residue for Yarrowia lipolytica growth and the positive effect of a pH of 7.5 on the fatty acid profile. 相似文献
3.
Albertine Léon Stéphane Pronost Jackie Tapprest Nathalie Foucher Béatrice Blanchard Geneviève André-Fontaine Claire Laugier Guillaume Fortier Roland Leclercq 《Journal of veterinary diagnostic investigation》2006,18(2):218-221
Studies were carried out to determine the cause of death in a prematurely born Thoroughbred foal that died 24 hours after birth. Necropsy revealed gross lesions suggestive of septicemia. A commercial Leptospira polymerase chain reaction (PCR) assay designed to specifically amplify the hemolysis-associated protein 1 (hap1) gene present only in pathogenic Leptospira strains detected the presence of Leptospira DNA in various tissues of the foal. Histologic examination of lung, liver, kidney, and myocardium revealed numerous spirochetes in Warthin-Starry-stained tissue sections. Results of PCR analysis and histologic examination suggested a leptospiral infection in the newborn foal. At the moment of death, the infection coexisted with a streptococcal-associated aspiration bronchopneumonia and postpartum septicemia. These findings indicate that the PCR assay based on the amplification of the hap1 gene represents a useful tool for specific detection of pathogenic leptospira in field samples taken from horses. 相似文献
4.
Tabouret G Lacroux C Andreoletti O Bergeaud JP Hailu-Tolosa Y Hoste H Prevot F Grisez C Dorchies P Jacquiet P 《Veterinary research》2003,34(2):231-241
Cellular and humoral local responses were investigated following repetitive artificial Oestrus ovis infections in lambs. The presence of larvae induced a huge local recruitment of either leucocytes (T and B lymphocytes, macrophages) or granulocytes (eosinophils, mast cells and globule leucocytes). This cellular response was more pronounced in the ethmoid and sinus (development sites of second and third instar larvae) than in the septum or turbinates where first instar larvae migrate. Infected lambs produced Oestrus ovis specific IgG and IgA antibodies in their mucus. This local humoral response was mainly directed against larval salivary gland antigens and not against larval digestive tract antigens. Compared to the control animals, the sinusal mucosa of infected animals was extremely thickened and the epithelium exhibited hyperplasia, metaplasia and eosinophilic exocytosis. The possible roles of these local immune responses in the regulation of O. ovis larvae populations in sheep are discussed. 相似文献
5.
Guillaume Sallé Carole Moreno Simon Boitard Julien Ruesche Aurélie Tircazes-Secula Frédéric Bouvier Mathias Aletru Jean-Louis Weisbecker Fran?oise Prévot Jean-Paul Bergeaud Cathy Trumel Christelle Grisez Emmanuel Liénard Philippe Jacquiet 《Veterinary research》2014,45(1):68
This study reports a functional characterization of a limited segment (QTL) of sheep chromosome 12 associated with resistance to the abomasal nematode Haemonchus contortus. The first objective was to validate the identified QTL through the comparison of genetically susceptible (N) and resistant (R) sheep produced from Martinik × Romane back-cross sheep. The R and N genotype groups were then experimentally infected with 10 000 H. contortus larvae and measured for FEC (every three days from 18 to 30 days post-challenge), haematocrit, worm burden and fertility. Significant differences in FEC and haematocrit drop were found between R and N sheep. In addition, the female worms recovered from R sheep were less fecund. The second step of the characterization was to investigate functional mechanisms associated with the QTL, thanks to a gene expression analysis performed on the abomasal mucosa and the abomasal lymph node. The gene expression level of a candidate gene lying within the QTL region (PAPP-A2) was measured. In addition, putative interactions between the chromosome segment under study and the top ten differentially expressed genes between resistant MBB and susceptible RMN sheep highlighted in a previous microarray experiment were investigated. We found an induction of Th-2 related cytokine genes expression in the abomasal mucosa of R sheep. Down-regulation of the PAPP-A2 gene expression was observed between naïve and challenged sheep although no differential expression was recorded between challenged R and N sheep. The genotyping of this limited region should contribute to the ability to predict the intrinsic resistance level of sheep. 相似文献
6.
Guillaume Gory Delphine N. Rault Laure Gatel Claire Dally Patrick Belli Laurent Couturier Eddy Cauvin 《Veterinary radiology & ultrasound》2014,55(5):552-560
Differential diagnoses for regurgitation and vomiting in dogs include diseases of the gastroesophageal junction. The purpose of this cross‐sectional study was to describe ultrasonographic characteristics of the abdominal esophagus and gastric cardia in normal dogs and dogs with clinical disease involving this region. A total of 126 dogs with no clinical signs of gastrointestinal disease and six dogs with clinical diseases involving the gastroesophageal junction were included. For seven euthanized dogs, ultrasonographic features were also compared with gross pathology and histopathology. Cardial and abdominal esophageal wall thicknesses were measured ultrasonographically for all normal dogs and effects of weight, sex, age, and stomach filling were tested. Five layers could be identified in normal esophageal and cardial walls. The inner esophageal layer was echogenic, corresponding to the cornified mucosa and glandular portion of the submucosa. The cardia was characterized by a thick muscularis, and a transitional zone between echogenic esophageal and hypoechoic gastric mucosal layers. Mean (±SD) cardial wall thicknesses for normal dogs were 7.6 mm (±1.6), 9.7 mm (±1.8), 10.8 mm (±1.6), 13.3 mm (±2.5) for dogs in the <10 kg, 10–19.9 kg, 20–29.9 kg and ≥30 kg weight groups, respectively. Mean (±SD) esophageal wall thicknesses were: 4.1 mm (±0.6), 5.1 mm (±1.3), 5.6 mm (±1), and 6.4 mm (±1.1) for the same weight groups, respectively. Measurements of wall thickness were significantly correlated with dog weight group. Ultrasonography assisted diagnosis in all six clinically affected dogs. Findings supported the use of transabdominal ultrasonography as a diagnostic test for dogs with suspected gastroesophageal disease. 相似文献
7.
Soukaina Bouissil Claire Gurin Jane Roche Pascal Dubessay Zainab El Alaoui-Talibi Guillaume Pierre Philippe Michaud Said Mouzeyar Cdric Delattre Cherkaoui El Modafar 《Marine drugs》2022,20(2)
In many African countries, the Bayoud is a common disease spread involving the fungus Fusarium oxusporum f. sp. albedinis (Foa). The induction of plant natural defenses through the use of seaweed polysaccharides to help plants against pathogens is currently a biological and ecological approach that is gaining more and more importance. In the present study, we used alginate, a natural polysaccharide extracted from a brown algae Bifurcaria bifurcata, to activate date palm defenses, which involve phenylalanine ammonia-lyase (PAL), a key enzyme of phenylpropanoid metabolism. The results obtained showed that at low concentration (1 g·L−1), alginate stimulated PAL activity in date palm roots 5 times more compared to the negative control (water-treated) after 24 h following treatment and 2.5 times more compared to the laminarin used as a positive stimulator of plant natural defenses (positive control of induction). Using qRT-PCR, the expression of a selection of genes involved in three different levels of defense mechanisms known to be involved in response to biotic stresses were investigated. The results showed that, generally, the PAL gene tested and the genes encoding enzymes involved in early oxidative events (SOD and LOX) were overexpressed in the alginate-treated plants compared to their levels in the positive and negative controls. POD and PR protein genes selected encoding β-(1,3)-glucanases and chitinases in this study did not show any significant difference between treatments; suggesting that other genes encoding POD and PR proteins that were not selected may be involved. After 17 weeks following the inoculation of the plants with the pathogen Foa, treatment with alginate reduced the mortality rate by up to 80% compared to the rate in control plants (non-elicited) and plants pretreated with laminarin, which agrees with the induction of defense gene expression and the stimulation of natural defenses in date palm with alginate after 24 h. These results open promising prospects for the use of alginate in agriculture as an inducer that triggers immunity of plants against telluric pathogens in general and of date palm against Fusarium oxysporum f. sp. albedinis in particular. 相似文献
8.
Fiona Da Riz Paul Higgs Guillaume Ruiz 《The Canadian veterinary journal. La revue veterinaire canadienne》2021,62(6):611
Cobalamin concentration is often assessed in clinical practice but little is known about the significance of hypercobalaminemia. The objective of this retrospective study was to identify the conditions associated with hypercobalaminemia in dogs and to investigate association with clinicopathological variables. Medical records of dogs having serum cobalamin measured between 2016 and 2018 were reviewed. One hundred sixty dogs were included and 47 (29%) showed hypercobalaminemia. Dogs with hypercobalaminemia had gastrointestinal (57%), hepatic (11%), neurological (11%), endocrine (9%), renal (4%), pancreatic (2%), and miscellaneous (6%) diseases. Overall, 11% had neoplasia. This distribution was not significantly different from that for hypocobalaminemic and normocobalaminemic dogs. There were significantly more dogs with hyperfolatemia in the hypercobalaminemia group. These results suggest that in clinical practice hypercobalaminemia is commonly identified in gastrointestinal and hepatic disease in dogs, but can also be seen with endocrine and neurological conditions. The frequency of hyperfolatemia alongside hypercobalaminemia may reflect common metabolic pathways. 相似文献
9.
Guillaume Roblot Damien Coudegnat Laurent Bleron Robert Collet 《Annals of Forest Science》2008,65(8):812-812
10.
Cardozo Ernesto Gómez Celentano Danielle Rousseau Guillaume Xavier Silva Hulda Rocha e Muchavisoy Henry Mavisoy Gehring Christoph 《Agroforestry Systems》2022,96(5-6):941-956
Agroforestry Systems - The potential of agroforestry systems (AFS) for atmospheric carbon sequestration in degraded tropical lands is of key interest for climate change and rural development... 相似文献