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1.
The role of Penicillia in ryegrass staggers   总被引:2,自引:0,他引:2  
Tremorgenic strains of Penicillium verrucosum var cyclopium, P canescens, P janthinellum, P novaezeelandiae and P estinogenum were isolated from the faeces of 15 of 23 affected sheep and cattle in eight of nine field outbreaks of ryegrass staggers. One tremorgenic strain of P griseofulvum was isolated from the faeces of one of 25 sheep grazing in unaffected flocks. Tremorgenic strains of P verrucosum var cyclopium, P canescens, P janthinellum and P estinogenum were also isolated from the A horizon of New Zealand soils. Since a large proportion of experimentally dosed live P verrucosum var cyclopium died during passage through the gut, the faecal evidence from naturally staggering animals suggests that at least some outbreaks of ryegrass staggers are caused by tremorgenic Penicillia and that their source may be soil.  相似文献   

2.
An outbreak of ringworm in Karakul sheep occurred during 1973 among the flocks of at least 14 farmers in South West Africa and the northern Cape Province. Infections spread from one farm to another as a result of introducing infected stud rams. On one farm a few cattle, a goat and a horse developed lesions after being in contact with infected sheep. Some of the attendants handling infected sheep also contracted the disease. Strains recovered from infected animals resembled Trichophyton verrucosum morphologically, but when grown on laboratory media they did not require an exogenous source of vitamins, which was found to be indispensable for strains of this species studied previously.  相似文献   

3.
An outbreak of ringworm in sheep in Ireland caused by Trichophyton verrucosum is described. The flock consisted of 110 sheep and two separate groups within the flock were affected. Eleven of the first group of 23 sheep and five of the second group of 25 sheep showed lesions. Contact with infected cattle and fomites contaminated by the cattle are believed to have caused the outbreak. An excellent response was obtained in both infected groups by treatment with griseofulvin at a dose rate of 7.5 mg/kg daily for seven days.  相似文献   

4.
Haemolytic activities of Trichophyton (T.) mentagrophytes were detected and characterized by qualitative and quantitative assays. On Columbia agar supplemented with blood from horses, cattle or sheep, T. mentagrophytes expressed a strong zone of complete haemolysis. No haemolytic activities could be detected in the closely related T. verrucosum var. ochraceum. The same results were obtained after cultivation of the fungi on sterile cellulose acetate filters placed on the surface on Columbia blood agar. After removal of the filter, complete haemolysis was detected below the colony of T. mentagrophytes. A soluble haemolysin from culture supernatant of this strain was isolated and partially purified. Specific haemolytic activity per mg protein was enriched 2.6-fold in filtrate F(1), a fraction obtained as filtrate after filtration through 3kDa cut-off membranes. The partially purified haemolysin was neither affected by proteinase K treatment, nor by high and low temperatures, suggesting that it represents a small peptide haemolysin. Accordingly, in a commercial enzymatic activity test only the crude culture filtrate, but none of the subsequent purification fractions showed reactivity. Evaluation of the specificity of the haemolysin using erythrocytes from different mammalian species revealed that sensitivity was highest to those of equines, followed by erythrocytes from sheep, cattle, swine, dogs and humans. None of the erythrocytes was lysed by filtrate F(1) from T. verrucosum var. ochraceum. Furthermore, different eukaryotic cell lines from different species were tested in their sensitivity to cytolytic activities of the haemolysin, but no membrane damage could be detected.  相似文献   

5.
The authors describe the finding and identification of ochratoxin A in fodder barley of Czechoslovak produce. The fungus Penicillium verrucosum var. verrucosum, which is an ample producer of ochratoxin A, was isolated from a sample of barley. The isolated fungus was cultivated on several substrates at different temperatures and the production of ochratoxin A was studied during cultivation. The authors believe that the ochratoxicoses of farm animals may also occur in Czechoslovakia and that it would be useful to study this mycotoxin in selected feeds.  相似文献   

6.
Recent epidemiological features of the zoonotic dermatophyte Trichophyton verrucosum were investigated in 294 calves from 20 farms located in Central Italy. By the combination of microscopic examinations and fungal cultures, the total prevalence rate of T. verrucosum infection was found to be high, with 87.7% of samples yielding positive results and 100% of farms being infected. Farm to farm prevalence of infection varied from 25% to 100% of the examined calves. Prevalence rates were higher in females than males (91.6% versus 84%), in >3-< or =6 than >6-< or =9 month old calves (89.8% versus 85.7%), in purebred than in crossbred (88.5% versus 81.8%), and in symptomatic than asymptomatic ones (95.7% versus 80.4%). T. verrucosum was as prevalent in semi-intensive as in intensive breeding system (88.2% versus 87.6%) but more prevalent in calves raised for meat rather than milk production (91.1% versus 84.9%), and reared under conventional than organic production management system (89.3% versus 82.6%). Prevalence rates were also higher when the cattle present in the farm were of mixed origin, rather than when the whole stock was purchased or was born in the farm (92% versus 88.2% and 85.7%), when other cattle in the farm were showing skin signs (90% versus 84.2%), and at least one case of human ringworm was recorded in the farm (90.9% versus 86.1%). No statistically significant association was found. Therefore, T. verrucosum infection may be more widespread in calves from Central Italy than it was previously thought to be. Calves of any sex, breed, age, and of any of the farm condition considered, are highly exposed to the risk of infection. As calves may play a considerable role as reservoirs of the infection, our results highlight the need to determine the incidence and the importance of T. verrucosum ringworm in personnel involved with cattle care in Italy and elsewhere.  相似文献   

7.
Of a group of seven calves, four were vaccinated against bovine ringworm with the vaccine Ringvac bovis LTF-130 (Alpharma, Oslo, Norway), while three calves were left unvaccinated. All calves were inoculated epicutaneously with a virulent strain of Trichophyton verrucosum . Clinical signs were recorded. In response to stimulation with trichophytin, in vitro interferon-γ (IFN-γ) production in whole blood cell cultures was assessed in samples obtained pre-and post-vaccination and pre- and post-inoculation. A commercial enzyme immunoas-say kit was used to measure IFN-γ levels (Bovigam, CSL, Victoria, Australia). Control calves developed typical ringworm lesions, whereas vaccinated calves did not. Following vaccination, release of IFN-γ in whole blood cell cultures indicated the presence of circulating trichophytin-specific lymphocytes. After inoculation with T. verrucosum , IFN-γ production was demonstrated in samples from both vaccinated and control calves. This study showed that vaccination with Ringvac bovis LTF-130 elicits a protective immune response suggesting involve-ment of the cellular branch of the immune system. Experimental infection of naïve nonvaccinated calves with T. verrucosum , also indicated stimulation of a cell-mediated immune response essential for resolution of lesions.  相似文献   

8.
The protective action of live avirulent vaccine against bovine trichophytosis, produced by the Bioveta National Corporation at Ivanovice na Hané, was very good and fully comparable with the earlier vaccine produced from the virulent live culture of Trichophyton verrucosum. Experimental challenge with a massive dose of a virulent strain of T. verrucosum produced only minor surface dermal changes in the calves vaccinated with these vaccines, but these changes spontaneously disappeared in a short time. In the control non-vaccinated calves, large and deep lesions were induced by the challenge, spreading to the neighbouring tissues. Compared with both live biopreparations, the protective effect of inactivated vaccine prepared by the irradiation of virulent vaccine with Co60 was much lower.  相似文献   

9.
The contamination of forages and grain feeds with ochratoxigenic moulds and ochratoxin A was examined. The investigations were carried out over a period of three years in all seasons. Feeds were found to be contaminated with moulds at a high level throughout the three research years. The highest percentage (95 to 100) of contaminated feed samples was noticed during the second year. Total viable counts of moulds established in 1 g of feed samples ranged from 0.5 to 7.8 x 10(6). Penicillium spp. were dominant in mycopopulations isolated from feeds. Ochratoxin-A producing moulds were present permanently. In the summer period of the second research year as much as 94% of the feed samples were contaminated by ochratoxigenic Penicillium species. P. verrucosum var. cyclopium P. verrucosum var. verrucosum, P. commune and P. chrysogenum, i.e. ochratoxin-producing moulds, were the most prevalent Penicillium species throughout the three-year investigation. Ochratoxin A was found in various feeds in all seasons, except in summer of the first research year. Concentrations of the toxin varied from traces to 400 micrograms/kg. It occurred consistently in the same types of feeds (hay, dried alfalfa, fresh alfalfa, concentrate, pelleted sugar beet pulp, corn silage).  相似文献   

10.
A new vaccine against ringworm, containing the inactivated Trichophyton verrucosum strain, was assessed on guinea pigs and calves under experimental conditions and on three herds of cattle under natural conditions. The vaccine elicited a distinct immune response of the cellular type. This type of immunity assessed by the migration inhibition test of leukocytes corresponded to the immunity evaluated by the challenge. In herds in which there were from 30 to 67% of naturally infected animals with T. verrucosum, two doses of the vaccine resulted in after 4 weeks a decrease of the number of animals with clinical changes from 40.5 to 100% depending on the group of animals under study.  相似文献   

11.
Tests were performed on 130 one-month-old calves. In 16 animals, treatment with a suspension of Trichophyton verrucosum culture at the dosage of 5 mil. conidia for an area of 10 x 10 of the clipped skin caused clinical trichophytic changes. The length of the incubation time was shorter in the calves scarified before inoculation of the infecting culture (10 to 13 days), as compared with the group of calves without scarification of the skin (11 to 19 days). Only 3 in 6 calves, infected by the same dose into non clipped skin, did contract trichophytosis, manifesting themselves as separate mycotic deposits, which appeared 26 to 35 days after inoculation. Trichophytic changes lasted longest in the group with scarification of the infected area. The ID50 in T. verrucosum and T. equinum cultures was about 1500 conidia per one calf in the case of the method of infecting into clipped scarified skin (area 100 sq cm). A 10 times lower dose (150 conidia per one calf) of the T. verrucosum suspension did not induce visible mycotic changes, but the T. equinum inoculation produced infection in one of 10 calves.  相似文献   

12.
The conglutinating factor in sheep serum was characterized utilizing its ability to react with sensitized erythrocytes which had been alexinated with horse complement. The conglutinating substance in sheep serum was inactivated by the action of 2-mercaptoethanol, did not require calcium ions for its activity, was not inhibited by N-acetyl-D-glucosamine or L-fucose sugars and did not react directly with zymosan. All these activities distinguish this serum factor from bovine conglutinin. These data show that the conglutinating factor in sheep serum is an immunoconglutinin. Reactivity of sheep immunoconglutinin with both heterologous and autologous complement was demonstrated.  相似文献   

13.
Kosovo, one of the countries in the Balkan Peninsula, has a long tradition in sheep farming, and sheep breeds share triple purpose breed characteristics: milk, meat and wool. Bardhoka sheep, also with triple productive profile, is an important sheep breed because of its economic value with its milk production. In this study, 24 mandibles of adult Bardhoka sheep (12 male and 12 female) aged between 2 and 5 were used. The sheep were acquired from slaughterhouse around Kosovo, and the mandibles were selected without any deformities from healthy sheep. After cleaning the mandibles, a total of 12 morphometric measurements were taken from each sample using digital calliper. The difference between female and male was statistically significant (p < .05) for measurement 11 (height of mandible level of alveolar edge of 3rd molar tooth). The mean value of measurement 11 in male individuals was 42.26 ± 3.96, and it had a higher value than in female individuals (39.37 ± 2.57). In the literature, knowledge related to mandible morphometry of Bardhoka sheep was insufficient. The aim of this study was to determine mean values from osteometric measurements of Bardhoka sheep mandible and obtain references with the values acquired.  相似文献   

14.
Calves at the age of one month were vaccinated with a lyophilized vaccine against bovine trichophytosis, or with an avirulent vaccine against bovine trichophytosis (mfd by Bioveta, Ivanovice in Haná). Prophylactic doses of the vaccines (15 mil. CFU of production strain Trichophyton verrucosum per calf) were used for immunization, and doses 10 times, 100 times and 1000 times lower. The calves were revaccinated with the same doses in 12 days after the first vaccination. Twenty-eight days later since revaccination, the vaccinated calves and a group of control nonvaccinated calves was challenged epicutaneously with a virulent strain of T. verrucosum. The protectiveness of both vaccines implanted at doses of 2 x 15 mil. and 2 x 1.5 mil. CFU per test animal was very good. No dermal lesion were observed in the challenged calves of these groups, or if any, they were not clear and could be observed for a short time. If the vaccines were used diluted at a ratio 10(-2) (150 thousand CFU of production strain), trichophytic lesions persisting for the whole period of observation were found in four of the seven calves vaccinated with a lyophilized vaccine against bovine trichophytosis and in two of the eight calves implanted an avirulent vaccine after challenge. Mycotic lesions were formed after challenge in all test animals in the groups vaccinated with doses of 2 x 15 thousand CFU of production strain per calf. The extent of these lesions was practically the same as in all nonvaccinated controls--on the surface of infected skin the hair was shed and scales and crusts were formed. A challenge strain of T. verrucosum was cultivated from these lesions.  相似文献   

15.
浅析青海省小尾寒羊的发展现状与方向   总被引:2,自引:0,他引:2  
郭继军 《家畜生态》2004,25(3):68-70
通过对青海省引进、纯繁、推广小尾寒羊的情况调查,适应性观察,以及杂交试验分析表明,从山东梁山、郓城等地引进的小尾寒羊在舍饲,羊舍饲条件下,能够适应青海省海拔较低的农区环境,较好的保持了原产地小尾寒羊的品种特性,产羔率220%,羔羊成活率85.67%。生长发育快,体格高大。小尾寒羊不是一个肉用品种,它的品种特性在于生长发育快、早熟、常年发情和多胎性,利用这一优势的有效途径是经济杂交。以小尾寒羊或其杂种一、二代羊为母本,选用良种肉用公羊进行杂交,建立高效、集约化的肉羊生产体系,生产优质羊肉是青海省小尾寒羊养殖的发展方向。  相似文献   

16.
The potential impact of extracts from forage plants on γδ T cell activity in ruminants was evaluated using an in vitro immunoassay. This study investigated whether plant extracts could prime γδ T cells via up-regulation of CD25 (interleukin-2 receptor alpha). Purified Sephadex LH-20 fractions, isolated from Viscum rotundifolium, Viscum verrucosum, Tapinanthus oleifolius and Grewia flava, were screened against γδ T cells on kid, lamb and calf peripheral blood lymphocytes. Condensed tannins (CT) from G. flava significantly primed γδ T cells in kids up to 64.75% at 10 μg/mL, which was statistically significant relative to the negative control at 22.66% (p=0.004). CT from T. oleifolius also induced priming of γδ T cells in kids, while fractions from V. rotundifolium and V. verrucosum induced minimal priming of γδ T cells. In contrast, there was no significant priming of γδ T cells from lambs and calves for any of the tested fractions (p>0.05). These findings suggest that CT from a selected range of Botswanan forage plants can stimulate the immune system in vivo in selected ruminant species and may participate in enhancing host innate immune responses.  相似文献   

17.
A first isolation of border disease virus (BDV) in Japan was from a pig on a farm without keeping any ruminants. Our previous study showed that this BDV, termed the FNK2012-1 strain, replicated inefficiently in swine-derived cells compared with those of ruminant origin. Pigs inoculated with this virus showed neither clinical symptoms nor viremia. In this study, we evaluated the pathogenicity of the FNK2012-1 strain in sheep, its natural host. The inoculated sheep showed clinical symptoms and transient viremia. Seroconversion was observed in the inoculated sheep. These results suggest that the FNK2012-1 strain was introduced from sheep and has not yet adapted to swine. Therefore, surveillance of border disease in Japan is necessary among both the swine and ruminant populations.  相似文献   

18.
在黄南州四县40个乡、场(次)采集绵羊血清2503份,用间接血凝试验检查衣原体抗体。结果:检出阳性血清415份,阳性率为16.58%。试验说明:黄南州境内绵羊衣原体流产分布地区广,感染率高,是引起绵羊流产的又一主要原因。  相似文献   

19.
Small ruminant lentiviruses (SRLVs) cause different clinical forms of disease in sheep and goats. So far in Spain, Maedi visna virus-like (MVV-like) sequences have been found in both species, and the arthritic SRLV disease has never been found in sheep until a recent outbreak. Knowing that arthritis is common in goats, it was of interest to determine if the genetic type of the virus involved in the sheep arthritis outbreak was caprine arthritis encephalitis virus-like (CAEV-like) rather than MVV-like. Alignment and phylogenetic analyses on nucleotide and deduced amino acid sequences from SRLV of this outbreak, allowed a B2 genetic subgroup assignment of these SRLV, compatible with a correspondence between the virus genetic type and the disease form. Furthermore, an isolate was obtained from the arthritic outbreak, its full genome was CAEV-like but the pol integrase region was MVV-like. Although its LTR lacked a U3 repeat sequence and had a deletion in the R region, which has been proposed to reduce viral replication rate, its phenotype in sheep skin fibroblast cultures was rapid/high, thus it appeared to have adapted to sheep cells. This outbreak study represents the first report on CAEV-like genetic findings and complete genome analysis among Spanish small ruminants.  相似文献   

20.
An outbreak of virulent footrot was investigated in a flock of 605 Merino cross-bred sheep in Bhutan. Conventional control methods in the preceding eight years had reduced its prevalence from 36-79% in different components of the flock to about 15% overall. Only one serogroup (B) of Dichelobacter nodosus was identified among 40 isolates cultured from affected sheep. A vaccine prepared from this strain was used in a pilot trial to compare the response of 14 treated and 14 untreated sheep. All affected, vaccinated animals in this trial healed quickly and were protected against re-infection while additional cases developed among untreated sheep during a period favourable for the spread of footrot. The serogroup B vaccine was administered to the whole flock for two successive years. No other footrot treatment was given during these or subsequent years. The whole flock was examined three times, foot by foot, for two years and twice yearly for another two years. When vaccination began there were 88 affected sheep in the flock, an affected sheep being defined as an animal with a foot-score of 2 or greater in one or more feet. There were neither affected sheep in the flock 30 days after the first dose of vaccine nor were any identified in later inspections. Virulent footrot, originating from the farm under investigation, persisted in neighbouring village flocks during this period. It was concluded that whole flock specific D. nodosus vaccination made a major contribution to the elimination of all clinical signs of footrot from the flock of 605 sheep where the condition had previously persisted for 10 years.  相似文献   

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