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101.
Tanay Bose Jolanda Roux Treena I. Burgess Christopher Shaw Michael J. Wingfield 《Forest Pathology》2019,49(6)
Eucalyptus grandis and its hybrids, as well as Acacia mearnsii, are important non‐native trees commonly propagated for forestry purposes in South Africa. In this study, we conducted pathogenicity trials to assess the relative importance of five commonly isolated Phytophthora spp. (Phytophthora alticola, P. cinnamomi, P. frigida, P. multivora and P. nicotianae) from the plantation environment on E. grandis and A. mearnsii seedlings. Overall E. grandis was more susceptible to the tested Phytophthora spp. than A. mearnsii. Phytophthora cinnamomi was the only pathogen that had a significant negative effect on both the host tree species, leading to a reduction in root and shoot weight as well as to death in the case of E. grandis. Phytophthora alticola and P. nicotianae exclusively affected E. grandis and A. mearnsii, respectively. This study updated the current knowledge on the pathogenicity of Phytophthora spp. on two important non‐native commercially propagated tree species from South Africa. 相似文献
102.
Sprenger SJ Halvorson DA Nagaraja KV Spasojevic R Dutton RS Shaw DP 《Avian diseases》2000,44(3):725-729
Ornithobacterium rhinotracheale is a gram-negative, rod-shaped, pleomorphic bacterium that has been isolated from flocks of turkeys and broilers from around the world. Infections cause respiratory disease, mortality, and growth suppression, or clinical signs of infection may be absent. In layers, there have been few reports of disease caused by O. rhinotracheale. This is the first report of O. rhinotracheale infection in United States layer flocks. 相似文献
103.
AIM: To measure the nutritive value of pasture in terms of digestible energy (DE) intake (DEI) and dry matter (DM) digestibility, and to determine the apparent absorption of macroelements in lactating Thoroughbred mares grazed on pasture. METHODS: DM intake (DMI) and DEI were determined from daily faecal DM output measured in grazing mares, divided by the DM indigestible fraction (1-digestible DM), measured in a digestibility trial using pasture-fed mares. Eight lactating mares and their foals, that had a mean age of 40 days, were grazed separately on 50x100 m areas of pasture and daily faecal DM outputs were recorded for 8 days. Five mares and their foals were then placed in individual bare 20x20 m corrals containing custom-made feeding stations for 14 days to determine the indigestible DM fraction. DM, gross energy content, crude protein (CP), soluble carbohydrate, acid detergent fibre (ADF), neutral detergent fibre (NDF), lipid, and macroelement composition of the pasture offered and faeces were determined and their digestibility and/or apparent absorption calculated. RESULTS: DM digestibility of the pasture was 0.6 and the DMI and DEI of a grazing 560 kg mare in early lactation nursing a foal growing at 1.34 kg/day was 13.6 (SE 0.8) kg/day and 146.9 (SE 8.4) MJ DE/day, respectively. Apparent absorptions of the macroelements measured were: Ca 0.75, P 0.43, Mg 0.63, Na 0.78, and K 0.72. CONCLUSIONS: Good quality ryegrass-white clover pasture that had a DE content of 10.8 MJ/kg DM, and a macroelement composition (g/kg) of Ca 3.33, P 3.0, Mg 1.67, Na 1.67, and K 24.2, will provide adequate DMI, DEI, and macroelement intake to lactating Thoroughbred mares. 相似文献
104.
105.
Silva BF Bassetto CC Shaw RJ Canavessi AM Amarante AF 《Veterinary parasitology》2012,186(3-4):437-444
Previous studies showed that Santa Ines (SI) hair sheep were more resistant to gastrointestinal nematode infections (GIN) than Ile de France (IF) sheep. The present experiment aimed to evaluate if that reported resistance difference against GIN also occurred against Oestrus ovis infestation and also to evaluate the influence of O. ovis infestation on the gastrointestinal nematodes (GIN) infections. SI (n=12) and IF (n=12) young male lambs were weaned at 2 months of age and moved to a paddock (0.3 ha) with Brachiaria decumbens grass, where they also received concentrate ration. The animals were kept together during the experimental period (September to early December 2009). Fecal and blood samples were taken from all animals every 2 weeks and body weight and nasal discharge score (oestrosis clinic signs) were recorded on the same occasion. In early December 2009, all lambs were sacrificed and O. ovis larvae and GIN were recovered, counted and identified according to the larval stage. All animals were infested by different larval instars of O. ovis without any statistical difference between breeds (P>0.05). The SI lambs had an average of 24.8 larvae, and the intensity of infection ranged between 14 and 39 larvae, while the IF lambs showed an average of 23.5 larvae with the minimum and maximum from 11 to 36 larvae, respectively. SI lambs presented the lowest nematode fecal egg counts (FECs) and the lowest mean numbers of Haemonchus contortus, Trichostrongylus colubriformis and Strongyloides papillosus, however, there was no significant differences between group means (P>0.05). Inverse relationship between numbers of O. ovis larvae and gastrointestinal nematodes was observed in both breeds. SI sheep showed a significant increase in blood eosinophils and total IgE serum levels and these variables were negatively correlated with nematode FEC. A negative correlation was observed between total IgE serum level and H. contortus burden in both breeds. In conclusion, there was no breed difference regarding O. ovis infestation and in each breed, animals with more nasal bot fly larvae tended to display smaller worm burden. 相似文献
106.
DR Link G Natale R Shao JE Maclennan NA Clark E Korblova DM Walba 《Science (New York, N.Y.)》1997,278(5345):1924-1927
A smectic liquid-crystal phase made from achiral molecules with bent cores was found to have fluid layers that exhibit two spontaneous symmetry-breaking instabilities: polar molecular orientational ordering about the layer normal and molecular tilt. These instabilities combine to form a chiral layer structure with a handedness that depends on the sign of the tilt. The bulk states are either antiferroelectric-racemic, with the layer polar direction and handedness alternating in sign from layer to layer, or antiferroelectric-chiral, which is of uniform layer handedness. Both states exhibit an electric field-induced transition from antiferroelectric to ferroelectric. 相似文献
107.
108.
Zhongqi Cheng Leda Lee Sara Dayan Michael Grinshtein Richard Shaw 《Journal of Soils and Sediments》2011,11(4):628-638
Purpose
Gardening (especially food growing) in urban areas is becoming popular, but urban soils are often very contaminated for historical reasons. There is lack of sufficient information as to the bioavailability of soil heavy metals to plants and human in urban environments. This study examines the relative leachability of Cr, Ni, As, Cd, Zn, and Pb for soils with varying characteristics. The speciation and mobility of these metals can be qualitatively inferred from the leaching experiments. The goal is to use the data to shed some light on their bioavailability to plant and human, as well as the basis for soil remediation. 相似文献109.
Traumatic body wall hernias (TBWH) are serious sequelae to traumatic injury in dogs and cats. During the study period, 26 dogs and 10 cats with surgically managed TBWH were identified. Five cases (four dogs, one cat) did not have their hernias identified during the first 24 hours of hospitalization. Bite wounds were the most common cause of TBWH, accounting for 54% of canine and 40% of feline hernias. Twelve cases (nine dogs, three cats) had serious intra-abdominal injuries diagnosed in addition to their TBWH. Seventy-three percent of dogs and 80% of cats survived to hospital discharge. In addition, the authors report the occurrence of a unique cause of herniation, termed an autopenetrating hernia. 相似文献
110.
Validation of the BioPRYN enzyme‐linked immunosorbent assay for detection of pregnancy‐specific protein‐B (PSPB) and diagnosis of pregnancy in American bison (Bison bison) 下载免费PDF全文
This study assessed the accuracy of the commercial BioPRYN® ELISA for the detection of pregnancy‐specific protein‐B (PSPB) using a single blood sample to determine pregnancy status in American bison (Bison bison). A total of 49 bison cows were used in the study, and sampled at two time‐points during the gestation period, fall and spring, correlating with early‐ to mid‐term gestation (average 62.9 days post‐mating) and mid‐ to late‐term gestation (average 229.2 days post‐mating), respectively. Sensitivity of the test during early‐ to mid‐term gestation sampling period (fall) was 87.1%, while specificity was 100%; sensitivity of the test during late‐term gestation sampling period (spring) was 96.3%, while specificity remained at 100%. In total, the test showed a total sensitivity of 91.4%, specificity of 100% and total accuracy of 93.8%, similar to domestic cattle. Use of the single‐sample BioPRYN® ELISA in American Bison for pregnancy diagnosis is economical and practical, minimizing animal handling time, frequency and subsequent stress while providing accurate results for pregnancy diagnosis at 62 days post‐mating. This method should be considered over more traditional pregnancy diagnosis methods for use in managed bison herds. 相似文献