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291.
A 48-yr-old female Asian elephant with a history of pododermatitis developed recurrent hematuria beginning in 2002. Transrectal ultrasonography and endoscopic examination in 2004 identified the uterus as the source of hematuria and excluded hemorrhagic cystitis. Treatment with Desloreline implants, antibiotics, and homeopathic drugs led to an improved general condition of the elephant. In July 2005, the elephant was suddenly found dead. During necropsy, the severely enlarged uterus contained about 250 L of purulent fluid, and histopathology revealed ulcerative suppurative endometritis with high numbers of Streptococcus equi ssp. zooepidemicus and Escherichia coli identified on aerobic culture. Additional findings at necropsy included: multifocal severe pododermatitis, uterine leiomyoma, and numerous large calcified areas of abdominal fat necrosis. Microbiologic culture of the pododermatitis lesion revealed the presence of Streptococcus agalactiae, Streptococcus equi ssp. zooepidemicus, Staphylococcus sp., Corynebacterium sp., and Entercoccus sp.  相似文献   
292.
293.
Tulathromycin is a new injectable macrolide antibiotic used for the treatment of pulmonary diseases of swine and cattle. In this study, 37 foals with sonographic evidence of lung abscesses were treated with tulathromycin (2.5mg/kg intramuscularly [IM] once weekly, group 1) and 33 foals (group 2) with a combination of azithromycin (10mg/kg per os [PO] once daily for the first seven days of therapy, thereafter every other day) and rifampin (10mg/kg PO twice daily). The bacterial aetiological agent was not determined. The foals were only mildly sick and the median number of pulmonary abscesses was 1.4 (group 1) and 1.6 (group 2). Thirty foals in each group were treated without modifying therapy protocols until all clinical signs of disease had subsided. Tulathromycin was administered for a mean of 53 days, and azithromycin/rifampin for 42 days. The following side effects were associated with tulathromycin (279 IM injections): self-limiting diarrhoea in 11 foals; elevated temperature in six foals, and swellings at the injection site in 12 foals. This study provides some evidence that tulathromycin is well tolerated and appears promising for the treatment of pulmonary abscesses in foals.  相似文献   
294.
Otarine Herpesvirus-1 (OtHV-1) is a gammaherpesvirus routinely detected in urogenital tumor tissues of adult sea lions dying during rehabilitation, To investigate the epidemiology of this virus and guide the development of a mathematical model of its role in the multifactorial etiology of cancer in California sea lions, polymerase chain reaction (PCR) amplification of an OtHV-1 specific fragment of the DNA polymerase gene was used to look for evidence of OtHV-1 infection in urogenital and pharyngeal swabs and peripheral blood mononuclear cells (PBMC) of sea lions of different ages. Samples were also examined from pregnant females and their late term in utero or aborted fetuses to investigate potential for vertical transmission. Prevalence of infection in 72 adult females was 22%, whereas it was 46% in 52 adult males, and was significantly lower in 120 juvenile animals (6%). OtHV-1 DNA was most often detected in the lower reproductive tract of the adult animals, especially the males, and rarely in the pharynx or urogenital tract of juvenile animals. These data suggest sexual transmission may an important route of transmission. Additional studies are required to confirm this mode of transmission. Additionally, the virus was detected in a single prematurely born pup, suggesting the possibility of perinatal transmission. No indication of a PBMC associated viremia was evident in adults using standard PCR or in juveniles using standard and real time PCR.  相似文献   
295.
Journal of Plant Diseases and Protection - The citrus industry is among the most important worldwide, but citrus plants are affected by a large number of diseases, such as Citrus Black Spot (CBS),...  相似文献   
296.
The aim of this study is to investigate the possibilities and the mechanisms of spring barley (Hordeum vulgare L.) cross-adaptation to different heavy metals after hardening with ozone (O3), drought and UV-B radiation. Dry shoot biomass, accumulation of superoxide (O2˙?) and malondialdehyde (MDA), and activities of enzymes superoxide dismutase (SOD), glutathione reductase (GR) and catalase (CAT) were measured after hardening and heavy metal treatments. Seedlings, exposed to ozone and drought prior to copper (Cu) treatment, showed significantly increased tolerance to this heavy metal. The most possible causes of cross-adaptation to this redox-active heavy metal, which triggered very strong oxidative stress in nonhardened barley seedlings, were increased CAT activity, mitigation of O2˙? accumulation and lipid peroxidation. Cross-adaptation to cadmium (Cd) was induced only by drought hardening. In this case, however, adaptation had lower effect on antioxidative enzymes, did not altered O2˙? accumulation and even slightly increased the intensity of lipid peroxidation. The study reveals that stimulation of CAT activity and mitigation of oxidative stress are the main reasons for plant adaptation to Cu; whereas cross-adaptation to Cd, heavy metal with much lower oxidative capacity, is determined by the mechanisms that are not related to oxidative stress directly.  相似文献   
297.
Meloidogyne enterolobii (syn. M. mayaguensis) has been reported to cause severe damage in commercial guava orchards and other plants in Central and South American countries. Considering the risk of introduction and dissemination of this pest in the European region, M. enterolobii was placed on the EPPO A2 list in 2010. The use of non-host fruit species is a recommended strategy to manage root-knot nematodes in infested guava orchards. This study screened 89 plant genotypes from 25 fruit plants of economic importance, plus two susceptible controls (guava and tomato) for its host status to M. enterolobii. Three to eight months after inoculation, nematode reproduction factor (RF) was used to characterize host suitability of fruit crops to this nematode. Ten banana genotypes, six Barbados cherries, one fig, two grape rootstocks and six melons were rated as good hosts for this nematode. Sixteen fruit plants behaved either as non-hosts or poor hosts to M. enterolobii, including assaí, atemoya, avocado, cashew nut, citrus, coconut, grape, jabuticaba, mango, mulberry, papaya, passion fruit, sapodilla, soursop, starfruit and strawberry. For the future, field experiments in areas infested by this nematode are essential to confirm the greenhouse results. These non-host fruit species can replace in the future eradicated guava trees in fields severely infested by this nematode and become an economic option for growers where M. enterolobii is considered a serious problem.  相似文献   
298.
Pratylenchus brachyurus is one of the main limiting factors of agricultural yield in annual crops, particularly due its difficult management. Methods to reduce populations are constantly sought, and the use of resistance inducers deserves attention. Thus, the study aimed to assess the effect of acibenzolar-S-methyl (ASM) application in different doses to P. brachyurus control in maize. Initially, 1000 specimens of P. brachyurus were inoculated in maize for the multiplication. After 60 days, the aerial part (AP) was discarded and maize was sown under the treatments: seed treatment (ST), application in the AP and ST?+?AP, in the doses of 0.125, 0.25, 0.5 and 1.0?g i.a./L. Vegetative and nematological parameters were assessed 60 days later. ASM did not affect plant growth, but reduced nematode population in all the treatments. The treatment methods did not differ and reduced the number of nematodes/g root by 64.25 to 80.14% compared to the control. The doses of 0.6, 0.51 and 0.65?g i.a./L promoted the most reductions in the number of nematodes/g root when applied in ST, AP and ST?+?AP, respectively. Thus, we recommend the use of ASM applied on shoot in a dose of 0.50?g i.a./L.  相似文献   
299.
Plant nutrition conditions are limited in naturally acidic soil due to harmful hydrogen and aluminium ions. More favourable conditions for plant nutrition (soil liming) will affect root qualitative and quantitative parameters and influence ecosystem stability. Four legume–grass swards were cultivated. The swards were a combination of one species of legume and two species of grasses: Trifolium pratense L., Trifolium repens L., Trifolium hybridum L., Medicago sativa L. (each of 50%) with Phleum pratense L. (35%) and Poa pratensis L. (15%). The aim of this study is to evaluate the root morphological and soil biological indicators of legume–grass swards under the first two years of development in soils with different pH levels.

Sward ecosystem development depends on the pH of the soil, sward species composition and soil biota. During the first year of sward development, soil pH had a significant influence on the morphology of root system. Sward‘s root mass and total root length was 2.4 and 2.2 times bigger in naturally acidic soil. This resulted in a change of biological parameters.

In the second year of sward development, soil pH had no significant influence on sward‘s root mass. However, under the impact of different soil pH, various sward‘s root systems were formed and the root C:N ratio had changed. It is observed that, regardless of the sward species composition and the year of development, at higher root C:N ratio soil microbial biomass was higher and CO2 emissions were lower in swards in naturally acidic soils.

Regardless of soil pH, different types of clover–grass swards promoted organic carbon immobilization in microbial biomass and, at the same time, stabilized the sward ecosystem in the top soil layer (soil respiration in 0–10 and 10–20?cm layers was lower) more effectively than the alfalfa–grass sward.  相似文献   
300.
Bioactive peptides with a variety of effects have been described from several nutritive proteins. They exhibit antimicrobial, blood-pressure lowering, antithrombotic, immunomodulatory, and cholesterol-modulating effects. In this study, we have examined whether peptides derived from food proteins might influence bile acid synthesis. A reporter gene cell line that carries a cholesterol 7alpha-hydroxylase promoter fragment fused to firefly luciferase ( cyp7a-luc) was used to screen for nutritive peptides affecting cyp7a expression, the enzyme catalyzing the rate-limiting step in bile acid synthesis. Proteolytic hydrolysates were prepared from soy protein and bovine casein with pepsin, trypsin, chymotrypsin, and elastase and size fractionated using ultrafiltration. Several bioactive hydrolysates could be identified that inhibited luciferase expression. Also, an activation of kinase (AKT, ERK, p38-MAPK) signaling could be observed. Selected hydrolysates were further fractionated by reversed-phase HPLC. Bioactive HPLC-fractions were obtained from casein but not from soy hydrolysates; however, activity could not be recovered in single peak fractions. Peptides in such fractions were identified by mass spectrometry. Five selected peptides from alpha S1-casein present in active fractions were synthesized, but none of these showed activity in the cyp7a-luc screening system. However, two of them activated MAP-kinase signaling similar to the hydrolysates, which suggests, that these peptides are involved in cyp7a regulation by the casein hydrolysates.  相似文献   
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