First-year growth response of cold-stored,nursery-grown aspen planting stock     

Lee A. Martens  Simon M. Landhäusser  Victor J. Lieffers 《New Forests》2007,33(3):281-295

This research examined the first year growth characteristics of cold stored and transplanted nursery-produced aspen (Populus tremuloides) seedlings (container and bareroot (BR)) and compared it to the growth of seedlings that had not been transplanted (established from germinants in the field) and therefore had an unrestricted root system (UR). Prior to planting, nursery-produced seedlings were placed in cold storage (−3°C) and root growth potential (RGP) and total non-structural carbohydrate (TNC) root reserves were tested at 0, 10, 75 and after 150 (container) and 190 days (BR) of storage. Both container and BR stock had much lower root to shoot ratios (RSRs) and root carbohydrate reserves compared to UR seedlings after 170 days. During storage, root reserves in container stock declined faster than in the BR and UR seedlings. RGP in all nursery stock was the highest after 75 days of storage, while longer storage resulted in shoot dieback and reduced root growth. After the first growing season, UR seedlings were one tenth the size of the nursery stock; however, in the second growing season they had no stem dieback and grew twice the height and stem diameter. The higher RSRs and root reserves in the UR seedlings was likely caused by early bud set in its first year of growth. This suggests that inducing bud set earlier in the growing regime might allow seedlings to increase root mass and carbohydrate reserves.  相似文献   

Inhibition of trypsin by condensed tannins and wine     

Gonçalves R  Soares S  Mateus N  de Freitas V 《Journal of agricultural and food chemistry》2007,55(18):7596-7601

Phenolic compounds are abundant vegetable secondary metabolites in the human diet. The ability of procyanidin oligomers and wine polyphenols to inhibit trypsin activity was studied using a versatile and reliable in vitro method. The hydrolysis of the chromogenic substrate N-benzoyl-d,l-arginine-p-nitroanilide (BApNA) by trypsin was followed by spectrophotometry in the presence and absence of condensed tannins and wine. A clear relationship between the degree of polymerization of procyanidins and enzymatic inhibition was observed. Trypsin activity inhibition was also detected in several types of wine. In general, the inhibition increased with the concentration of phenolic compounds in wines. These results may be relevant when considering these compounds as antinutritional factors, thereby contributing to a reduced absorption of nutrients.  相似文献   

Effects of growing conditions on purple corncob (Zea mays L.) anthocyanins     

Jing P  Noriega V  Schwartz SJ  Giusti MM 《Journal of agricultural and food chemistry》2007,55(21):8625-8629

Purple corn ( Zea mays L.) has been used for centuries as a natural food colorant in South America and, more recently, in Asia and Europe. However, limited information is available on the factors affecting their anthocyanin concentration and profiles. In this study, 18 purple corn samples grown under different conditions in Peru were evaluated for quantitative and qualitative anthocyanin composition as well as total phenolics. High variability was observed on monomeric anthocyanin and phenolic contents with yields ranging from 290 to 1333 mg/100 g dry weight (DW) and from 950 to 3516 mg/100 g DW, respectively, while 30.5-47.1% of the total phenolics were anthocyanins. The major anthocyanins present were cyanidin-3-glucoside, pelargonidin-3-glucoside, peonidin-3-glucoside, cyanidin-3-maloylglucoside, pelargonidin-3-maloylglucoside, and peonidin-3-maloylglucoside, and 35.6-54.0% of the anthocyanins were acylated. Potassium sources/concentrations on the soil and seedling density did not significantly affect anthocyanin composition. The growing location affected anthocyanin levels and the percentage of anthocyanins to total phenolics ( p < 0.01) and should be taken into account when choosing a material for color production.  相似文献   

Porcine circovirus type 2 decreases the infection and replication of attenuated classical swine fever virus in porcine alveolar macrophages     

Yu-Liang Huang  Victor Fei Pang  Ming-Chung Deng  Chia-Yi Chang  Chian-Ren Jeng 《Research in veterinary science》2014

Recently, it has been noted that porcine circovirus type 2 (PCV2) infection adversely affects the protective efficacy of Lapinized Philippines Coronel (LPC) vaccine, an attenuated strain of classical swine fever virus (CSFV), in pigs. In order to investigate the possible mechanisms of the PCV2-derived interference, an in vitro model was established to study the interaction of LPC virus (LPCV) and PCV2 in porcine alveolar macrophages (AMs). The results showed that PCV2 reduced the LPCV infection in AMs and the levels of PCV2-derived interference were dose-dependent. The PCV2-derived interference also reduced the replication level of LPCV in AMs. The full-length PCV2 DNA and its fragment DNA C9 CpG-ODN were involved in the reduction of LPCV infection in AMs, whereas UV-inactivated PCV2 was not. In addition, a moderate negative correlation between the LPCV antigen-containing rate and IFN-γ production was observed, and had a dose-dependent trend with the level of PCV2-inoculation. The results of the present study may partially explain how PCV2 infection interferes with the efficacy of LPC vaccine.  相似文献   

Detection of retinoid receptors in non-neoplastic canine lymph nodes and in lymphoma     

Carlos H. de Mello Souza  Victor E.O. Valli  Barbara E. Kitchell 《The Canadian veterinary journal. La revue veterinaire canadienne》2014,55(1):1219-1224

This study evaluated the difference in retinoid receptor expression between non-neoplastic lymph nodes and nodal lymphoma in dogs. Retinoid receptor expression was evaluated by immunohistochemistry in 32 canine lymph nodes. The lymph nodes had been previously diagnosed as non-neoplastic (6 normal and 7 hyperplastic lymph nodes) and B- and T-cell lymphoma (19 cases). Immunohistochemistry for retinoic acid receptors and retinoid-X receptors (and their subtypes α, β, and γ) was performed in all cases. In addition, immunohistochemistry for CD3 and CD79a was performed in all lymphoma cases. Non-neoplastic lymphocytes were negative for all retinoid receptors. Retinoic acid receptor-γ was detected in 100% of B-cell lymphoma and 78% of T-cell lymphoma, while retinoid X receptor-γ was positive in 78% of T-cell lymphoma cases. When normal lymph node architecture was still present, a contrast between retinoid-negative benign cells and retinoid-positive malignant cells was clear. Retinoid receptors were expressed in neoplastic, but not in benign lymphocytes, suggesting their value for both diagnosis and treatment of canine lymphoma.  相似文献   

Evaluation of hepatitis E virus infection between different production systems of pigs in Brazil     

Marconni Victor da Costa Lana  Noemi Rovaris Gardinali  Raquel Aparecida Sales da Cruz  Letícya Lerner Lopes  Gustavo Sousa Silva  João Garcia Caramori Júnior  Anderson Castro Soares de Oliveira  Marcos de Almeida Souza  Edson Moleta Colodel  Amauri Alcindo Alfieri  Caroline Argenta Pescador 《Tropical animal health and production》2014,46(2):399-404

The objectives of this study were to (1) investigate the occurrence of hepatitis E virus (HEV) in pigs from large-scale and family-scale farms, (2) genetically characterize the strains isolated, and (3) study the pathogenesis of swine HEV infection via immunohistochemistry. A total of 50 pigs from 10 farms in Mato Grosso State, Brazil were divided according to type of production system into either large-scale farms (n?=?5) or family-scale farms (n?=?5). Samples of liver, gallbladder, small and large intestines, bile, and feces from the pigs were analyzed by nested PCR with primers targeting the ORF2 region of HEV and by immunohistochemistry. Of the eight HEV-positive samples from pigs of family-scale farms, phylogenetic analysis revealed that seven of the swine HEV isolates clustered with subtype 3b of genotype 3 and one isolate was categorized with subtype 3 f. The HEV antigen was detected mainly in the small intestine samples from family-scale farms, suggesting an early stage HEV infection. HEV was not detected in the samples of pigs from large-scale farms, reinforcing the need for additional studies to evaluate the risk of transmission of HEV to humans from pigs from family-scale farms in Mato Grosso State.  相似文献   

Evaluation of the effectiveness of Duddingtonia flagrans and Monacrosporium thaumasium in the biological control of gastrointestinal nematodes in female bovines bred in the semiarid region     

Manoel Eduardo da Silva  Fabio Ribeiro Braga  Luana Alcântara Borges  Jair Mendes de Oliveira  Walter dos Santos Lima  Marcos Pezzi Guimarães  Jackson Victor de Araújo 《Veterinary research communications》2014,38(2):101-106

Brazil has a herd of 212 million cattle and 171 million hectares of pastures that produce approximately 96 % of Brazilian beef. The Brazilian production system enables animal infection by endoparasites, which are considered one of the main obstacles for the development of this industry and are responsible for considerable economic losses. The control of parasitic diseases is performed via the administration of antiparasitic drugs, but they leave residues of the products in the treated animal, affect non-target organisms and select resistant strains of the parasites. The species D. flagrans and M. thaumasium are promising and sustainable alternatives for controlling gastrointestinal helminths of ruminants and other herbivores. In this study, we evaluated the efficacy of isolates of these species, formulated in a sodium alginate matrix and administered twice a week, to reduce the number of environmental infective larvae of gastrointestinal nematodes that affect prepubescent zebu females. The treated animals presented fewer eggs and a lower number of infective larvae per gram of faeces (p?<?0.05). The pastures occupied by treated animals showed a statistically significant reduction (p?<?0.05) of the number of L₃ and, furthermore, the genera Cooperia sp., Haemonchus sp., and Oesophagostomum sp. were the most prevalent. The average weight of the animals did not differ statistically (p?>?0.05) among the treated and control groups. The use of sodium alginate pellets as vehicle for delivery of the fungus mycelia D. flagrans (isolate AC001) and M. thaumasium (isolate NF34A) proved effective in controlling trichostrongylids in prepubescent cows bred in the semi-arid region, with an effective reduction in the number of infective larvae in the pastures.  相似文献   

A spatial risk assessment of bighorn sheep extirpation by grazing domestic sheep on public lands     

Tim E. Carpenter  Victor L. Coggins  Clinton McCarthy  Chans S. O’Brien  Joshua M. O’Brien  Timothy J. Schommer 《Preventive veterinary medicine》2014

Bighorn sheep currently occupy just 30% of their historic distribution, and persist in populations less than 5% as abundant overall as their early 19th century counterparts. Present-day recovery of bighorn sheep populations is in large part limited by periodic outbreaks of respiratory disease, which can be transmitted to bighorn sheep via contact with domestic sheep grazing in their vicinity. In order to assess the viability of bighorn sheep populations on the Payette National Forest (PNF) under several alternative proposals for domestic sheep grazing, we developed a series of interlinked models. Using telemetry and habitat data, we characterized herd home ranges and foray movements of bighorn sheep from their home ranges. Combining foray model movement estimates with known domestic sheep grazing areas (allotments), a Risk of Contact Model estimated bighorn sheep contact rates with domestic sheep allotments. Finally, we used demographic and epidemiologic data to construct population and disease transmission models (Disease Model), which we used to estimate bighorn sheep persistence under each alternative grazing scenario. Depending on the probability of disease transmission following interspecies contact, extirpation probabilities for the seven bighorn sheep herds examined here ranged from 20% to 100%. The Disease Model allowed us to assess the probabilities that varied domestic sheep management scenarios would support persistent populations of free-ranging bighorn sheep.  相似文献   

Discovery of a new avian bornavirus genotype in estrildid finches (Estrildidae) in Germany     

Dennis Rubbenstroth  Volker Schmidt  Monika Rinder  Marko Legler  Victor Max Corman  Peter Staeheli 《Veterinary microbiology》2014,168(2-4):318-323

Avian bornaviruses (ABV) are known to be the causative agent of proventricular dilatation disease (PDD) in parrots and their relatives (Psittaciformes). A broad range of ABV genotypes has been detected not only in psittacine birds, but also in other avian species including canary birds (Serinus canaria forma domestica) and Bengalese finches (Lonchura striata f. dom.), which are both members of the order songbirds (Passeriformes).During this study 286 samples collected from captive and wild birds of various passerine species in different parts of Germany were screened for the presence of ABV. Interestingly, only three ABV-positive samples were identified by RT-PCR. They originated from one yellow-winged pytilia (Pytilia hypogrammica) and two black-rumped waxbills (Estrilda troglodytes) from a flock of captive estrildid finches in Saxony. The ABV isolates detected here were only distantly related to ABV isolates found in passerine species in Germany and Japan and form a new genotype tentatively called ABV-EF (for “estrildid finches”).  相似文献   

Intra- and interspecific phenotypic characteristics of fish-pathogenic Edwardsiella ictaluri and E. tarda   总被引：1，自引：0，他引：1  

Victor S Panangala  Craig A Shoemaker  Shawn T McNulty  Covadonga R Arias  & Phillip H Klesius 《Aquaculture Research》2006,37(1):49-60

Intra‐ and interspecific characteristics of fish‐pathogenic Edwardsiella ictaluri, and E. tarda were determined by numerical analysis of gel electrophoresed protein profiles, fatty acid methyl esters (FAMEs) and immunoblotting. The 18 E. ictaluri isolates revealed a high degree of homogeneity (70% similarity or higher) in their protein profiles and 95% similarity in their FAME, while the nine E. tarda isolates revealed 30% similarity in their protein profiles and 95% similarity in their FAME. Immunoblots probed for antigenic epitopes with goat antiserum produced against E. ictaluri and E. tarda, respectively, revealed that E. ictaluri were more homogeneous compared with the E. tarda isolates. Overall, there was a considerable degree of relatedness between the two species. Our findings suggest that phenotypically E. ictaluri represents a clonal bacterial population structure compared with the less monomorphic E. tarda.  相似文献