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101.
This article describes the histopathology of grossly normal mesenteric lymph nodes (MLNs) of New Zealand farmed red deer (Cervus elaphus). Eighty MLNs were sourced from 10 deer from 5 North Island herds and 5 South Island herds classified as low risk and high risk of Mycobacterium avium subspecies paratuberculosis (MAP) infection, respectively. Fixed sections were stained with hematoxylin and eosin; Ziehl-Neelsen; and, selectively, periodic acid-Schiff, Perl's, and Sudan black. Positive Ziehl-Neelsen stain, follicular hyperplasia, capsular eosinophil infiltration, focal granulomas, foci of macrophages containing lipopigment, parasitic granulomas, and calcified foci are described and severity graded where appropriate. Animal age, sex, and herd of origin are variably associated with the presence of one or more features. Trabecular fibrosis and dilated edema-filled sinusoids are described. These observations allow differentiation between likely nonpathologic histologic features in deer MLNs and features possibly attributable to infection with a pathogen such as MAP. 相似文献
102.
103.
Bridgett M. West Peggy Liggit Daniel L. Clemans Steven N. Francoeur 《Water, air, and soil pollution》2011,217(1-4):473-489
We examined water quality indicators (pH, temperature, turbidity, total phosphorus, and fecal coliform density) and bacterial antibiotic resistance (prevalence, conjugative transfer, and genetic linkage of resistance elements) at locations impacted by confined animal feeding operations (CAFOs) and compared them to nearby reference sites. Sites located upstream and downstream of two wastewater treatment facilities were also compared. Sites near CAFO farms had poor water quality (elevated total phosphorus and turbidity), while water quality remained relatively good downstream of wastewater treatment plants. High proportions of antibiotic-resistant bacteria were observed at all study sites, and frequent conjugative transfer of resistance was observed in laboratory assays. Out of a total of 830 environmental bacterial isolates, 77.1% were resistant to only ampicillin, while 21.2% were resistant to combinations of antibiotics including ampicillin (A), kanamycin (K), chlorotetracycline (C), oxytetracycline (O), and streptomycin (S). Multi-drug-resistant bacteria were significantly more common at sites impacted by CAFO farms. In conjugation assays, 83.3% of the environmental isolates transferred one or more antibiotic resistance genes to a laboratory strain of Salmonella typhimurium. A subset of multi-drug-resistant (A, C, and O) isolates was screened for specific tetracycline resistance genes and class I and II integrons. None of the screened isolates (n?=?22) were positive for integrons, while 13 isolates contained resistance genes for tet (B) and tet (C). Our results indicate that CAFO farms not only impair traditional measures of water quality but may also increase the prevalence of multi-drug-resistant bacteria in natural waters. 相似文献
104.
Maria Orfanoudaki Anja Hartmann Julia Mayr Flix L. Figueroa Julia Vega John West Ricardo Bermejo Christine Maggs Markus Ganzera 《Marine drugs》2021,19(6)
This study presents the validation of a high-performance liquid chromatography diode array detector (HPLC-DAD) method for the determination of different mycosporine-like amino acids (MAAs) in the red alga Bostrychia scorpioides. The investigated MAAs, named bostrychines, have only been found in this specific species so far. The developed HPLC-DAD method was successfully applied for the quantification of the major MAAs in Bostrychia scorpioides extracts, collected from four different countries in Europe showing only minor differences between the investigated samples. In the past, several Bostrychia spp. have been reported to include cryptic species, and in some cases such as B. calliptera, B. simpliciuscula, and B. moritziana, the polyphyly was supported by differences in their MAA composition. The uniformity in the MAA composition of the investigated B. scorpioides samples is in agreement with the reported monophyly of this Bostrychia sp. 相似文献
105.
106.
King Kevin M. West Jonathan S. 《European journal of plant pathology / European Foundation for Plant Pathology》2022,162(3):751-756
European Journal of Plant Pathology - Phoma stem canker / blackleg is an internationally important disease of Brassicas including B. napus (oilseed rape, OSR), caused by multiple genetic subclades... 相似文献
107.
Endophyte effects on reproduction of a root-knot nematode (Meloidogyne marylandi) and osmotic adjustment in tall fescue 总被引:2,自引:0,他引:2
In a 2 × 2 × 2 factorial experiment, plants of one genotype of tall fescue ( Festuca arundinacea ) were grown in soil in pots in a glasshouse on two occasions. The treatments were either with (E+) or without (E–) infection by the fungal endophyte Neotyphodium coenophialum ; with (N+) or without (N–) inoculation by the root-knot nematode Meloidogyne marylandi ; and with or without water deficit stress. In the first experiment, nematode numbers after 5 weeks had increased 10 times in the E–/N– watered pots and 22 times in the E–/N+ stressed plants. Root dry weight was decreased in all E–/N+ pots, compared with E–/N–. In contrast, nematode numbers in all E+/N+ pots decreased to nearly zero and root dry weight was unaffected. Osmotic adjustment in the growing zone of stressed plants was –0·35 MPa in E–/N– pots, but only –0·10 MPa in E–/N+ pots. Osmotic adjustment was greatest (–0·64 MPa) in E+ pots of both nematode treatments and almost no nematodes survived in the N+ pots. In the second experiment, there was complete nematode mortality in the E+ pots. Plant water relations were unaffected by treatments, however. It is concluded that endophyte-enhanced persistence of tall fescue in M. marylandi -infested soils that are prone to drought may be explained at least partly by endophyte protection of roots from nematode damage. Nematode inhibition by the endophyte may operate in addition to direct influences of the endophyte on enhancing drought tolerance of the host. 相似文献
108.
The occurrence and possible cause of intrahepatic cholestasis in two shorthorn cows from a herd with a history of weight loss, low milk yield and chronic intermittent diarrhoea are discussed. 相似文献
109.
L. Occhipinti J. Novak R. Yamamoto G. B. E. West K. M. Lam T. B. Farver 《Preventive veterinary medicine》1986,3(6):581-588
An agar gel precipitation (AGP) test was used to study the epidemiology of marble spleen disease (MSD) on a large pen-raised pheasant farm with a prior history of MSD. Tests conducted during early season egg production (March 1983) on previously infected breeders, poults from these breeders, and MSD-free hens introduced onto the farm, indicated absence of MSD antibodies (and clinical disease) during the breeding season (February–July 1983). Thus, a carrier state or egg transmission could not be demonstrated. The disease did not occur in late summer (September) in the same area of the ranch where it was diagnosed for the past 5 seasons. The AGP test was useful in confirming the pattern of the disease spread which moved erratically but within the general area of the index pen. Antibodies were detected in penmates approximately 10–15 days after the first observed mortality, but did not persist after the disease had run its course. Our observations suggest that the reservoir of the virus exists in the environment, and mechanical transmission (caretaker, equipment etc.) is important in sustaining the disease during an outbreak. 相似文献
110.