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1.
Quinoa offers a promising alternative for staple food, considering its outstanding nutritional value and tolerance to abiotic stresses. To develop breeding programmes in quinoa, a reliable crossing method for increasing the genetic variation is required. In the following study, we aimed to develop segregating populations in quinoa. We tested the efficiency of three different crossing methods (hand emasculation, warm water emasculation and no emasculation). Moreover we developed a two-stage selection strategy based on morphological traits and molecular markers for the selection of hybrid plants. We reported hand emasculation to be the most efficient crossing method, followed by warm water emasculation and no emasculation. Our results demonstrated that crosses in quinoa can be successfully performed, despite its complicated flower structure and high self-pollination rate. Additionally, we developed 30 segregating populations from crosses between accessions of different origins with varying phylogenetic relationship, which offers a promising perspective for quinoa breeding programmes in the future.  相似文献   
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lNTRoDUCTloNInChina,onlyafewexperimentshavebeenperfbrmedtotestinsecticidessusceptibletopreventconesandseedsfrominsectdamage(Anonymousl986,GaoBuquetal.l99l,YueShukuil992,LiuYikong1993).Moreover,thesetestsonlyconsistedofsprayingchemi-cals,thatmayinduceharInfulconsequencesuponenvironment.TheintensifiedeffoftofafforestationinNortleasternChinarecentlyrequiredtoestablishlnyenumbersofseedorchards,aswellasparent-trCestands,inordertoprovideforesterswithhigh-qualityseeds,especiallyinlarch.Thispr…  相似文献   
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Background

Atopic dermatitis (AD) is the most common canine allergic skin disease and can significantly affect the quality of life of affected dogs. Treating canine AD with ciclosporin has been a subject of great interest in recent years. Many studies have provided substantial evidence of ciclosporin efficacy and safety in canine AD management, and for several years ciclosporin has been recognised as a major component of canine AD multimodal therapy. As a chronic condition, canine AD requires life-long medical management and treatment success relies in large part on product ease of administration. Two studies were conducted to assess the comparative voluntary acceptance and consumption of Cyclavance® (Virbac), a new oral liquid formulation of ciclosporin, and Atopica® (Novartis) either added to a small quantity of kibbles (study 1) or administered directly into the dog’s mouth (study 2).

Results

Over the course of the two studies 70 dogs assessed each of the ciclosporin formulations and 320 individual tests were performed for each tested product. Immediate prehension (in less than 2 seconds) occurred significantly more often with Cyclavance® (90.6% of the tests) than with Atopica® (14.4% of the tests) when products were mixed with 30 grams of dry food (p < 0.001). Moreover, Cyclavance® was significantly more often easily accepted than Atopica® (99.3% vs 27.1% of the tests, respectively) when products were administered directly into the dogs’ mouth (p < 0.0001). Cyclavance® was also more often totally consumed (98.3% of the tests) than Atopica® (2.2% of the tests) when mixed with a small amount of food (p < 0.001). However, both products were totally consumed once administered directly into the dogs’ mouth.

Conclusions

By facilitating cicloporin administration and consumption, Cyclavance® liquid formulation offers an interesting alternative to capsules that may improve dosing compliance and therefore the ability to benefit from the therapeutic effects in the long-term treatment of canine AD.  相似文献   
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In developed countries, most of hepatitis E human cases are of zoonotic origin. Swine is a major hepatitis E virus (HEV) reservoir and foodborne transmissions after pork product consumption have been described. The risk for HEV-containing pig livers at slaughter time is related to the age at infection and to the virus shedding duration. Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) is a virus that impairs the immune response; it is highly prevalent in pig production areas and suspected to influence HEV infection dynamics. The impact of PRRSV on the features of HEV infections was studied through an experimental HEV/PRRSV co-infection of specific-pathogen-free (SPF) pigs. The follow-up of the co-infected animals showed that HEV shedding was delayed by a factor of 1.9 in co-infected pigs compared to HEV-only infected pigs and specific immune response was delayed by a factor of 1.6. HEV shedding was significantly increased with co-infection and dramatically extended (48.6 versus 9.7 days for HEV only). The long-term HEV shedding was significantly correlated with the delayed humoral response in co-infected pigs. Direct transmission rate was estimated to be 4.7 times higher in case of co-infection than in HEV only infected pigs (0.70 and 0.15 per day respectively). HEV infection susceptibility was increased by a factor of 3.3, showing the major impact of PRRSV infection on HEV dynamics. Finally, HEV/PRRSV co-infection – frequently observed in pig herds – may lead to chronic HEV infection which may dramatically increase the risk of pig livers containing HEV at slaughter time.

Electronic supplementary material

The online version of this article (doi:10.1186/s13567-015-0207-y) contains supplementary material, which is available to authorized users.  相似文献   
7.
The red kite (Milvus milvus) occurs in a relatively small area in the southwestern Palearctic region, with population strongholds in Central Europe. Following strong human persecutions at the beginning of the 20th century, populations have receded, particularly in peripheral areas and islands. In order to describe and compare levels of genetic diversity and phylogeographic patterns throughout its entire distribution in Europe, sequence variation of a 357 bps part of the mitochondrial DNA control region was assessed in eight populations and 105 individuals. Overall, results indicate that population declines have affected red kite mtDNA variation. We found low levels of genetic diversity (values of nucleotide diversity ranging from 0 in Majorca island to 0.0062 in Central Europe), with only 10 distinct haplotypes, separated by low levels of genetic divergence (mean sequence divergence = 0.75%). Highest haplotype and nucleotide diversities match with demographic expectations, and were found in Central European and Central Spanish samples, where present strongholds occur, and lowest values in the declining southern Spanish and insular samples. Φst estimates indicated moderate gene flow between populations. Phylogeographic patterns and mismatch distributions analyses suggest central European regions may have been colonized from southern glacial refugia (in the Italian or Iberian peninsulas). Interspecific phylogenetic comparisons and divergence date estimates indicated the genetic split between the red kite and its closely related species, the black kite (Milvus migrans), might be relatively recent. The low level of genetic variation found in the red kite mitochondrial control region, compared to the black kite, is likely the result of relatively recent divergence (associated with founder events), successive bottlenecks and small population sizes. As there are several ongoing projects aimed at reinforcing populations in countries such as the United Kingdom, Italy or Spain, our results may prove useful for the genetic management of the species.  相似文献   
8.
A comparison of gene content and genome architecture of Trypanosoma brucei, Trypanosoma cruzi, and Leishmania major, three related pathogens with different life cycles and disease pathology, revealed a conserved core proteome of about 6200 genes in large syntenic polycistronic gene clusters. Many species-specific genes, especially large surface antigen families, occur at nonsyntenic chromosome-internal and subtelomeric regions. Retroelements, structural RNAs, and gene family expansion are often associated with syntenic discontinuities that-along with gene divergence, acquisition and loss, and rearrangement within the syntenic regions-have shaped the genomes of each parasite. Contrary to recent reports, our analyses reveal no evidence that these species are descended from an ancestor that contained a photosynthetic endosymbiont.  相似文献   
9.
OBJECTIVE: To evaluate efficacy of 2 deltamethrin emulsifiable concentrates that differed on the basis of vehicle (methyl glycol acetate [AMG] or 2-propylene glycol 1-methyl ether acetate [AMP]) for the treatment of sheep with mange. ANIMALS: 30 ewes between 11 months and 7 years old that weighed 16 to 71 kg and were naturally infested with Psoroptes ovis. PROCEDURE: Sheep were randomly allocated into 3 groups (13 sheep in group AMP, 13 sheep in group AMG, and 4 negative-control sheep). Each sheep was dipped twice (10-day interval between dippings) in the assigned formulation. Assessment of efficacy was performed on days 3, 7, 14, 21, 28, 35, 42, 49, 56, and 63 after the first dipping. Efficacy was assessed by determining the number of eggs or live mites on those days, as well as regrowth of wool at the end of the study. RESULTS: Psoroptic mange infestation was maintained in the 4 control sheep throughout the study. We did not detect live Psoroptes mites in scrapings after day 7 (AMP group) or after day 14 (AMG group). No parasites were seen after day 14 in either treatment group. Therefore, efficacy was 100% for both treatment groups from days 14 to 63. CONCLUSIONS AND CLINICAL RELEVANCE: The 2 formulations of deltamethrin were equally able to eradicate Psoroptes infestation of sheep after 2 dippings performed in accordance with the label recommendations.  相似文献   
10.
The aim of this experiment was to evaluate the significance of neonatal environment on feed efficiency. For that purpose, rabbits from a line selected for residual feed intake (RFI) during 10 generations (G10 kits) were cross‐fostered with non‐selected control does (i.e., G0 line), and reciprocally. In parallel, sibs were fostered by mothers from their original line. Nine hundred animals were raised in individual (N = 456) or collective (N = 320) cages. Traits analysed in this study were body weight at 32 days and at 63 days, average daily gain (ADG), feed intake between weaning and 63 days (FI), feed conversion ratio (FCR) and RFI. The maternal environment offered by does from the line selected for RFI deteriorated the FCR of the kits, independently of their line of origin, during fattening (+0.08 ± 0.02) compared to FCR of kits nursed by G0 does. The line, the type of housing and the batch were significant effects for all the measured traits: G10 kits were lighter than their G0 counterparts at 32 days (?82.9 ± 9 g, p < 0.0001) and at 63 days (?161 ± 16 g, p < 0.0001). They also had a lower ADG (?2.36 ± 0.36 g/day, p < 0.0001), RFI (?521 ± 24 g/day, p < 0.0001) and a lower FI (?855 ± 31 g, p < 0.0001), resulting in a more desirable feed efficiency (FCR: ?0.35 ± 0.02). There was no significant difference in the contrast of G10 and G0 performances between collective and individual/digestive cages (p > 0.22): ?2.35 g/day versus 2.94 g/day for ADG, ?0.39 versus ?0.40 for FCR, ?577 g versus ?565 g for RFI and ?879 g versus ?859 g for FI, respectively). Thus, no genotype‐by‐environment (housing) interaction is expected at the commercial level, that is, no re‐ranking of the animals due to collective housing.  相似文献   
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