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Infected Sheep (infected + sheep)

Distribution by Scientific Domains

Medical Sciences	50%
Life Sciences	50%

Selected Abstracts

Combined S99/RB51 antigen for complement fixation test for serological diagnosis of brucellosis in cattle and sheep

JOURNAL OF APPLIED MICROBIOLOGY, Issue 5 2002
R. Adone
Aims: To assess the efficiency of a single antigen for the complement fixation (CF) test, prepared by combining Brucella abortus smooth strain 99 (S99) with Brucella abortus rough strain RB51(RB51), in detecting cattle and sheep infected or vaccinated with Brucella spp. Methods and Results: Serum samples from B. abortus -infected and RB51-vaccinated cattle were tested by the CF test using S99, RB51 and the combined S99/RB51 as antigens. Likewise, serum samples from Brucella melitensis -infected, RB51-vaccinated and Brucella ovis- infected sheep were tested by the CF test using S99, RB51, hot saline (HS) and combined S99/RB51 as antigens. Comparative analysis of the CF results showed that no reduction of sensitivity or specificity occurs when S99/RB51 antigen is used instead of specific antigens used separately. Conclusions: The results of this study indicated that combined S99/RB51 antigen used in the CF test, because of its specificity and sensitivity, could be used in animal brucellosis surveillance systems to improve the efficiency of the preliminary screening of herds. Significance and Impact of the Study: This study proposes an improved antigen for the CF test for the epidemiological survey of animal brucellosis. It could represent advantages over standard protocols because of its ability to detect antibody responses following infection or vaccination withBrucella strains of rough and smooth phenotype. [source]

Prevalence and intensity of Oestrus ovis in Akkaraman sheep in the Konya region of Turkey

MEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2006
U. USLU
Abstract Slaughterhouse surveys to determine the prevalence and intensity of larval Oestrus ovis Linnaeus (Diptera: Oestridae) in sheep, were conducted monthly for 1 year in Konya, Turkey. A total of 624 sheep, selected at random, were examined and 59% were found to be infested by O. ovis. A total of 8801 larvae were collected, of which 68.9% were first-stage, 19.1% second-stage and 12% third-stage larvae. All three larval stadia were seen in each month of the year. The larval intensity for infected sheep was 23.9, with 16.48 L1, 4.55 L2 and 2.87 L3. The monthly prevalence ranged from 34.6% in January to 76.9% in October. The largest number of larvae (180) was obtained from a sheep in August (122 L1, 52 L2 and 6 L3). The infestation rate was higher in 4,6-year-old sheep, at 72.6%. The infestation rates were 64.4% in female and 47.5% in male sheep. [source]

Antibody-dependent cell-mediated cytotoxicity to newly excysted juvenile Fasciola hepatica in vitro is mediated by reactive nitrogen intermediates

PARASITE IMMUNOLOGY, Issue 9 2001
D. Piedrafita
Passive intraperitoneal transfer of sera from Fasciola hepatica- infected sheep, cattle or rats can protect naive rats from F. hepatica infection, suggesting a parasite killing mechanism within the peritoneal cavity that is dependent on the presence of parasite-specific antibody. We investigated antibody-dependent cell-mediated cytotoxicity by resident peritoneal lavage cell populations, containing large numbers of monocytes/macrophages, as a potential host resistance mechanism by which juvenile flukes could be killed within the peritoneal cavity of naive rats. Comparative studies were conducted using cell populations containing large numbers of monocytes/macrophages from sheep. The results demonstrate that monocyte/macrophage-rich lavage cell populations from rat and sheep differ substantially in their ability to generate nitric oxide . Only resident rat peritoneal lavage cells were able to mediate antibody-dependent cell-mediated cytotoxicity against newly excysted juvenile liver fluke. The mechanism of cytotoxicity was dependent on, and directly proportional to, the production of nitric oxide and required attachment of effector cells to the newly excysted juvenile liver fluke tegument, which occurred following the addition of sera from F. hepatica -infected animals. This is the first report demonstrating a mechanism of cell-mediated cytotoxicity to newly excysted juvenile liver fluke. [source]

Longitudinal study of the spread of ovine Johne's disease in a sheep flock in southeastern New South Wales

AUSTRALIAN VETERINARY JOURNAL, Issue 4 2005
L RAST
Objective The aim of this study was to apply whole flock testing over time to determine the prevalence, distribution and spread of infection in a recently infected flock, with a view to planning intervention strategies for disease control. Procedure Serology, pooled faecal culture (PFC) and histology were used to determine the distribution and persistence of infection in a sheep flock in south east New South Wales between 1997 and 2002. Partial flock testing was done up to June 2000, after which annual whole flock testing, using PFC was performed. Results Faecal shedding of M a paratuberculosis was not detected in home-bred sheep until 7 years after the introduction of infected sheep in 1993. For at least 7 years there was clustering of infection and shedding within two age groups only. The infected groups appeared to have been exposed to infection (mycobacterial contamination) at an early age (< 12 months) and commenced shedding at 5 years of age or older. Groups that were exposed to contamination as adults did not shed detectable amounts of M a paratuberculosis during the study period. Conclusion Clustering of detectable infection in age groups of sheep that were exposed as lambs was a feature on this farm, providing indirect evidence of finite duration of survival of M a paratuberculosis on pasture and the influence of age on the susceptibility of sheep to develop detectable M a paratuberculosis infection. Spread of infection occurred very slowly and was probably related to the long incubation period (exposure to shedding interval) of 5 years observed on this farm. The findings suggest that partial flock culling, selective grazing management and vaccination could lead to a reduction in mycobacterial contamination on farm to a level at which patent infection no longer occurs. Better understanding of disease spread within flocks over time through flock profiling using PFC will help in devising surveillance strategies (including testing protocols for market assurance testing) to detect infected flocks where there has been clustering and slow spread of infection. [source]