cattle diseases

..However, diagnostic tests showed that none of the animals in the case herds was infected with M a paratuberculosis...

..A sensitivity analysis showed the largest effect on costs was due to milk yield effects. For example, changing milk production loss from 0 to 5% for BVD increased the costs for the disease by 266%...

..The few routine biosecurity measures that were investigated in this study were generally not related to the seroprevalences of these farms...

..The early detection of PTB in calves is a challenge that requires further exploration of new methods to confirm infection status. These new testing methods should be both affordable and compatible with regular husbandry practices...

..Removal of seropositive, clinically unaffected cows and their daughters would be necessary to reduce infection with MAP attributable to congenital or peri-parturient transmission from dam to daughter...

..The importance of using ELISA and cultures is emphasized by this study but it is necessary to continue with the gammaIFN test development for early detection of the disease...

..Environmental sampling was an effective and inexpensive method of identifying herds infected with Mycobacterium avium ssp. paratuberculosis...

..For the best positive predictive value of a KELA for moderate to heavy fecal shedding, the cutoff values should be determined based on the apparent within-herd prevalence in a herd...

..High KELA values indicate heavy fecal shedding, but the KELA is not useful in identifying low and moderate shedders that can require up to 236 days to have a significant increase in KELA value...

..The results indicated that for sheep the interferon-gamma test may be useful for determining if a flock has been exposed to ovine Johne's disease...

..If these preventive measures were taken, the probability of undetected Map infections in closed 'Map-free' herds was decreased substantially...

..4% (99% CI, 7.7%, 11.1%) and the true prevalences for the northern, central and southern regions were 14.1% (99% CI, 9.6%, 18.65%), 7.5% (99% CI, 5.6%, 9.4%), and 10.6% (99% CI, 5.9%, 15.6%), respectively...

..3% and 9.1% were seropositive for Neospora caninum, respectively, while 28.1% of dairy herds had unvaccinated animals with titres > or = 1:64 for Bovine viral diarrhea virus...

..Despite this, it appears as if the method is a useful approach for herd-classification for most herds in the Danish dairy industry...

..These antibodies can be detected by ELISA with a test strategy that is different for younger and older cows. We suggest testing younger cows more frequently than older cows and that testing should be done prior to 350 d in milk...

..Environmental sampling is another diagnostic tool that veterinarians and dairy producers can use to determine herd infection status for MAP...

..This study provides evidence of the value of the VJDHSP in providing economic value to participants and supports the promotion of VJDHSP herds as a source of replacement cattle of low infection risk for MAP...

..That all herds of this study were seropositive for neosporosis and the within-herd prevalence was considerable raises questions about how far the infection is spread in other dairy areas of Costa Rica...

..However, also evidence was found for an unexplained ongoing horizontal transmission after the initial point source exposure...

..Shedding of Map from infected cats was not evaluated. The epidemiologic role of Map-infected feral cats on dairy farms requires further investigation...

..0 had assumed a 50% decrease in within-herd prevalence but Version 2.0 assumed a stable within-herd prevalence. Culture of pooled faecal samples provides a high-sensitive, high-specific, low-cost test for herd-certification programs...

..001). On dairy farms low faecal consistency was correlated with C. parvum infection (chi(2), P<0.05). Both C. parvum and C. bovis were identified, although in one beef calf C. suis was found...

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..CONCLUSION: Dairy cattle pose the highest risk of all the slaughter-age animals tested. Some of the identified risk factors can be overcome by improved management practices, especially in relation to hygiene...

..Nevertheless, control and prevention practices are indicated to avoid contamination of animal products...

..4). E. coli from calves treated with antibiotics within 5 days prior to sampling were also more likely to be increasingly multiply resistant than E. coli from calves not exposed to individual antibiotic therapy (OR = 2.0)...

..Calves aged 5-24 months that had been moved within the last 2 weeks had a higher risk, but risk was reduced if fed barley silage. Cows fed grain or molasses had a higher risk of excreting VTEC O157...

..coli O157:H7 (22 of 60 days versus 13 of 60 days) were higher in sawdust-bedded herds. The choice of bedding material used to house mature dairy cows may impact the prevalence of E. coli O157:H7 on dairy farms...

..Within the study population, E. coli O157:H7 REDP subtypes were disseminated with considerable frequency among farms in close geographic proximity, and nonbovine sources may contribute to the transmission of this organism between farms...

..e. the subjects chosen for test evaluation should reflect the distribution of animals in the population where the test is intended to be used...

..An estimated upper limit of prevalence of S strain M a paratuberculosis infection in susceptible exposed cattle in the OJD high prevalence area of New South Wales is 0.8%, assuming a common prevalence within herds...

..Pools of 10 cows are the better option to determine or monitor the herd status. A whole-herd ELISA is the least expensive way to determine the status of individual cows but has a lower Se and Sp than individual culture...

..For a given ELISA S/P ratio, older cows and those with lower 305 ME milk production relative to other cows in the herd were significantly more likely to be shedding MAP in their feces at the end of lactation...

..M. paratuberculosis infection, and not just clinical Johne's disease, decreases milk, fat, and protein yields, thus increasing the estimated cost of paratuberculosis to the US dairy industry...

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..Moreover, the FCM is objective, technically easy and can be automated for handling large numbers of samples. This novel assay might form the basis of a highly sensitive and subspecies-specific test for the diagnosis of JD...

..e., sensitivity and specificity)...

..A higher percentage of infected herds was detected if follow-up bacterial culture was not used, but this test strategy was associated with a high probability of misclassifying uninfected herds...

..When this study is compared with a similar study performed in Austria 1999, a significant increase of positive cattle and farms could be seen in Austria...

..At the cow and herd levels, milk ELISA performed equivalent to serum ELISA using fecal culture as a reference for MAP infection and has the advantage of decreased labor costs on farms that use Dairy Herd Improvement Association testing...

..Testing of random-source cattle, bought as herd replacements, can partially mitigate the risk of introduction of M. a. paratuberculosis but not as well as by using low-prevalence source herds (level-3 VJDHSP), with or without testing...

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..Therefore, Bayesian analysis was the preferred method for Map that lacks a gold-standard and usually has low cow-level prevalence...

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..In conclusion, the IFN-gamma test may be applied for screening of cattle of 1 and 2 years of age for exposure to M. paratuberculosis and the antibody ELISAs from 3 years of age...

..Diagnostic sensitivity of PCR for fecal, blood, milk, and liver samples in these advanced subclinically infected cows was 87%, 40%, 96%, and 93%, respectively...

..A rather striking result is the finding of atypical mycobacteria in feces of 75 cattle (48.3%). Among these isolates, M. avium ssp. avium, M. thermoresistibile, and M. hassiacum/M. buckleii have been identified so far...

..529. Overall, the sensitivities of the ELISAs when compared to tissue culture were low. The apparent advantage of the unabsorbed ELISA with respect to sensitivity is at the cost of lowered specificity and test accuracy...

..CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that the indirect ELISA used on milk samples may be a convenient method of detecting paratuberculosis in dairy herds...

..In this study, change in S/P was not a useful predictor of infection status in seronegative cows...

..CONCLUSIONS AND CLINICAL RELEVANCE: Annual importation rate, herd size, and whether cows in the herd had clinical signs typical of MAP infection were associated with the risk that individual cows would be seropositive for MAP infection...

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..CONCLUSIONS AND CLINICAL RELEVANCE: Use of pooled fecal samples from 10 cows was a cost-effective tool for herd screening and may provide a good estimate of the percentage of MAP-infected cows in dairy herds with a low prevalence of MAP...

..MAP is spread mainly by buying of animals, therefore a certification program for paratuberculosis free herds is urgently necessary as well as an improvement of diagnostic methods...

..In addition, contamination of bulk tank milk samples with M. paratuberculosis does occur in seropositive herds, even in some with negative fecal cultures...

..paratuberculosis fecal culture, ranged from 27.6% +/- 6.5% to 57.1% +/- 8.3%, depending on whether 1, 2, or all 3 individual fecal samples in the positive fecal pool were culture positive...

..For certification programs, only ELISA-A is recommended because in a large number of nonsuspect herds specificity remained almost 100%...

..Purpose-specific tests are required to appropriately interpret and use test results for management of paratuberculosis, and relevant covariates, such as age, should be included when possible...

..paratuberculosis in its feces. If used judiciously and interpreted quantitatively, these ELISAs are useful tools in support of paratuberculosis control programs in dairy herds...

..Pooling of fecal samples and testing with the GB-PCR assay are not recommended. Additional studies with qRT-PCR and fecal pools are required...