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871.
872.
873.
The bloodsuckling abomasal parasite Haemonchus contortus is the most pathogenic worm in sheep and goats. High prevalences of anthelmintic-resistant isolates make H. contortus difficult to control. Detecting the most anaemic animals could support a targeted selective treatment approach. Leaving the rest of the flock untreated would generate a refuge for anthelmintic-sensitive parasites. South-African researchers tried the FAMACHA-Eye-Colour-Chart for anaemic sheep and goats with good success. Field studies, carried out in Northern Germany on naturally infected sheep and goats showed, that at a comparatively low prevalence of H. contortus the FAMACHA-test proved not being sufficient in detecting all animals with high fecal egg counts. Under these conditions there was no satisfying reliability to identify small ruminants for selective deworming only based on the FAMACHAEye-Colour-Test. But if not working hours are the limiting factor, the repeated score could support the selection of pale animals in need to be treated. 相似文献
874.
The aim of the study was to determine the diagnostic value of measuring serum amyloid A (SAA) concentrations in milk of individual ewes and in farm bulk milk for monitoring udder health. Udder health was calculated by examining a randomly selected group of seven flocks at each farm visit by means of California mastitis test and bacteriological examination of 5749 milk samples. SAA was determined additionally in 267 randomly selected milk samples from six flocks. Thirty-one bulk milk samples from these farms were tested for SCC and SAA levels. Subclinical infections were detected in 29.5% of samples whereas no clinical infections were observed. Intramammary infected udder halves showed significantly elevated SAA concentrations (121.3+/-25.3 microg/ml) in milk compared to the levels of healthy udder halves (8.0+/-1.9 microg/ml; p<0.001). SAA was significantly elevated in sheep with elevated CMT scores and positive bacteriological results. Bulk milk SAA levels ranged from 18.6+/-6.7 to 37.4+/-14.1 microg/ml and showed a positive correlation with bSCC (r=0.38, p=0.018) but not with percent infected glands (r=0.022, p=0.453). This study demonstrated that SAA levels in milk can be used to detect subclinical mastitis in individual ewes whereas further investigations are needed to determine the value of measuring SAA in bulk milk for monitoring flock udder health. 相似文献
875.
Keratinolytic properties of two dermatophytes (Microsporum gypseum, Trichophyton mentagrophytes) and three moulds (Scopulariopsis brevicaulis, Alternaria alternata, Geotrichum candidum) isolated from diseased equine hooves were examined to improve the understanding of pathogenic mechanisms leading to equine onychomycosis. Equine hoof horn material and skin, as well as hoof keratin and dermal keratin extracted from corresponding tissues, were used as sole carbon and nitrogen sources in five test tubes for each fungus. Within 18 days, supernatants of all tubes were repeatedly examined for keratinolytic activity by SDS-PAGE and Western blot analysis. In addition, fungal growth rates were determined to identify the preferred tissue of the individual fungi. Among the fungi examined, M. gypseum was the most keratinolytic species, followed by T. mentagrophytes and S. brevicaulis. In the concentration applied, the moulds A. alternata and G. candidum showed minimal keratinolytic activity. With respect to growth rates, M. gypseum favoured hoof horn material, S. brevicaulis and G. candidum preferred skin as a keratin source, whereas for the other two fungi no clear preference was detectable. 相似文献
876.
Boillée S Yamanaka K Lobsiger CS Copeland NG Jenkins NA Kassiotis G Kollias G Cleveland DW 《Science (New York, N.Y.)》2006,312(5778):1389-1392
Dominant mutations in superoxide dismutase cause amyotrophic lateral sclerosis (ALS), a progressive paralytic disease characterized by loss of motor neurons. With the use of mice carrying a deletable mutant gene, expression within motor neurons was shown to be a primary determinant of disease onset and of an early phase of disease progression. Diminishing the mutant levels in microglia had little effect on the early disease phase but sharply slowed later disease progression. Onset and progression thus represent distinct disease phases defined by mutant action within different cell types to generate non-cell-autonomous killing of motor neurons; these findings validate therapies, including cell replacement, targeted to the non-neuronal cells. 相似文献
877.
We established superfluidity in a two-state mixture of ultracold fermionic atoms with imbalanced state populations. This study relates to the long-standing debate about the nature of the superfluid state in Fermi systems. Indicators for superfluidity were condensates of fermion pairs and vortices in rotating clouds. For strong interactions, near a Feshbach resonance, superfluidity was observed for a broad range of population imbalances. We mapped out the superfluid regime as a function of interaction strength and population imbalance and characterized the quantum phase transition to the normal state, known as the Pauli limit of superfluidity. 相似文献
878.
Vicente J Höfle U Garrido JM Fernández-De-Mera IG Juste R Barral M Gortazar C 《Veterinary research》2006,37(1):107-119
We describe the distribution of tuberculosis-like lesions (TBL) in wild boar (Sus scrofa) and red deer (Cervus elaphus) in Spain. Animals with TBL were confirmed in 84.21% of mixed populations (n=57) of red deer and wild boar and in 75% of populations of wild boar alone (n=8) in central and southern Spain (core area). The prevalence of TBL declined towards the periphery of this region. In the core area, the prevalence ranged up to 100% in local populations of wild boar (mean estate prevalence 42.51%) and up to 50% in red deer (mean estate prevalence 13.70%). We carried out exploratory statistical analyses to describe the epidemiology of TBL in both species throughout the core area. Prevalence of TBL increased with age in both species. Wild boar and red deer mean TBL prevalence at the estate level were positively associated, and lesion scores were consistently higher in wild boars than in red deer. The wild boar prevalence of TBL in wild boar did not differ between populations that were or were not cohabiting with red deer. Amongst the wild boars with TBL, 61.19% presented generalized lesions, and the proportion of generalized cases was similar between sex and age classes. In red deer, 57.14% of TBL-positive individuals presented generalized lesions, and the percentage of generalized cases increased with age class, but did not differ between the sexes. These results highlight the potential importance of wild boar and red deer in the maintenance of tuberculosis in south central Spain. 相似文献
879.
Steinbach T Bauer C Sasse H Baumgärtner W Rey-Moreno C Hermosilla C Damriyasa IM Zahner H 《Veterinary parasitology》2006,139(1-3):115-131
The study was undertaken to evaluate adverse effects of larvicidal treatment in horses naturally infected with cyathostomins. Out of 24 ponies kept on pasture, four animals were housed in September and anthelmintically cured to serve as worm-free controls (group C-0). The others were housed in December. Eight animals each were treated 8 weeks later with 5 x 7.5mg/kg fenbendazole (FBZ) or 1 x 0.4 mg/kg moxidectin (MOX). Four animals remained untreated (group C-i). Two, 4, 6 and 14 days after the end of treatment two animals of each of the treated groups were necropsied together with group C-0 and C-i animals. Infected animals before treatment showed weight loss, eosinophilia, increased plasma protein and globulin contents. Treatment was followed by weight gain and temporal plasma protein and globulin increase. Proportions of CD4+ and CD8+ T lymphocytes in the peripheral blood did not differ between the groups before treatment but dropped significantly temporally after FBZ treatment. Group C-0 was worm-free at necropsy. Group C-i animals contained variable numbers of luminal and tissue cyathostomins. Histological sections showed larval stages in the lamina propria und submucosa surrounded by macrophages. Either treatment was effective against luminal parasites and reduced the number of larvae in the bowel wall beginning 4-6 days after FBZ and 6-14 days after MOX treatment. Histologically, as a first reaction after FBZ application T lymphocytes accumulated around morphologically intact L4 in the submucosa. Subsequently T lymphocytes associated with eosinophils infiltrated the submucosa. Parasites became enclosed by granulomas with eosinophils adhering to and invading the larvae which started to disintegrate on day 4. Later on, particularly on day 14 inflammation extended into the mucosa and was frequently associated with ulcerations. Third stage larvae in general and L4 in the lamina propria, however, seemed not to be affected until day 14 and even then, parasites did usually not generate extensive inflammation. After MOX treatment severe morphologically detectable alterations of tissue larvae could not be observed earlier than day 14. Different from FBZ treatment, larvae disintegrated and were obviously resorbed without causing severe inflammation in the gut wall. In conclusion treatment with either drug was efficacious against tissue larvae of cyathostomins but there may be different clinical consequences: in contrast to MOX effects, killing of larvae due to FBZ was associated with severe tissue damage, which clinically may correspond to reactions caused by synchronous mass emergence of fourth stage larvae, i.e., may mimic larval cyathostominosis. 相似文献
880.
Saelinger CA Lewbart GA Christian LS Lemons CL 《Journal of the American Veterinary Medical Association》2006,229(2):266-268
OBJECTIVE: To determine prevalence of Salmonella spp in samples collected from wild North American turtles. ANIMALS: 94 wild North American turtles of 6 species in 2 genera. DESIGN: Prospective microbiologic study. PROCEDURES: A convenience sample of wild North Carolina turtles admitted to a veterinary college was evaluated for Salmonella spp by use of standard techniques via microbiologic culture of cloacal swab and fecal samples. Gastrointestinal mucosa samples were also collected at necropsy from turtles that died or were euthanized. Cloacal swab samples were also collected from wild pond turtles for bacteriologic culture. Controls were established by use of wild-type Salmonella Typhimurium LT2. RESULTS: 94 turtles were tested for Salmonella spp; Salmonella spp were not detected in any sample. By use of a pathogen-prevalence and sample-size table, the true prevalence of Salmonella spp was estimated as < 5%. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggested that wild turtles in central North Carolina may not be active shedders or carriers of Salmonella spp. Despite this 0% prevalence of infection, proper hygiene practices should be followed when handling wild turtles. 相似文献