scholarly journals Mycobacterium aviumSubspeciesparatuberculosisand Bovine Leukemia Virus Seroprevalence and Associated Risk Factors in Commercial Dairy and Beef Cattle in Northern and Northeastern China

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Wu-Wen Sun ◽  
Wen-Fa Lv ◽  
Wei Cong ◽  
Qing-Feng Meng ◽  
Chun-Feng Wang ◽  
...  
Keyword(s):  
Risk Factors ◽  
Beef Cattle ◽  
Bovine Leukemia Virus ◽  
Large Scale ◽  
Leukemia Virus ◽  
Herd Size ◽  
Northeastern China ◽  
Herd Level ◽  
Source Sample ◽  
Associated Risk Factors

Mycobacterium aviumsubspeciesparatuberculosis(MAP) and bovine leukemia virus (BLV) are important pathogens, commonly responsible for economical loss to cattle farms all over the world, yet their epidemiology in commercial dairy and beef cattle in China is still unknown. Thus, from September 2013 to December 2014, a large-scale seroprevalence study was conducted to determine the seroprevalence and identify herd-level risk factors associated with MAP and BLV infection. The source sample was 3674 cattle from 113 herds in northern and northeastern China. Antibodies against MAP and BLV were detected using ELISA tests. At animal-level, the seroprevalence of antibodies against MAP and BLV was 11.79% (433/3674) and 18.29% (672/3674), respectively. At herd-level, the seroprevalence of antibodies against MAP and BLV was 20.35% and 21.24% (24/113), respectively. Herd size was identified to be associated with MAP infection while herd size and presence of cattle introduced from other farms were significantly associated with BLV infection. Further research is needed to confirm these findings and improve the knowledge of the epidemiology of these two pathogens in these regions and elsewhere in China.

scholarly journals Seroprevalence, Risk Factors and Molecular Identification of Bovine Leukemia Virus in Egyptian Cattle

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 319
Author(s):  
Abdelfattah Selim ◽  
Eman A. Manaa ◽  
Abdullah D. Alanazi ◽  
Mohamed S. Alyousif
Keyword(s):  
Risk Factors ◽  
Dairy Cattle ◽  
Bovine Leukemia Virus ◽  
Leukemia Virus ◽  
Significant Risk ◽  
Control Program ◽  
Effective Control ◽  
Economic Losses ◽  
Genetic Classification ◽  
Associated Risk Factors

Bovine leukemia virus (BLV) is distributed worldwide and affects dairy cattle causing severe economic losses. The BLV has been serologically reported in Egypt, but few studies have evaluated its associated risk factors and genetic classification. Therefore, this study assessed risk factors associated with BLV infection and identified the genetic diversity of the Egyptian strain. The study was conducted on 500 dairy cattle distributed in four Governorates located in Northern Egypt. Overall, the seroprevalence of BLV infection among Egyptian dairy cattle was 18.2%. The grazing cattle in the losing house system had higher odds for BLV seropositivity, and bad practice such as the use of a single needle or one plastic glove for more than one animal was considered a significant risk factor for BLV infection. Besides, the sequencing and phylogenetic analysis for one Egyptian BLV strain was performed, and the obtained results confirmed the clustering of Egyptian BLV strain into genotype-1. The assessment of associated risk factors for BLV infection and determination of its genetic classification are essential to implement an effective control program.

scholarly journals Prevalence of Bovine Leukemia Virus Antibodies in US Dairy Cattle

2018 ◽  
Vol 2018 ◽  
pp. 1-8 ◽  
Author(s):  
Rebecca M. LaDronka ◽  
Samantha Ainsworth ◽  
Melinda J. Wilkins ◽  
Bo Norby ◽  
Todd M. Byrem ◽  
...  
Keyword(s):  
Dairy Cattle ◽  
Dairy Cows ◽  
Bovine Leukemia Virus ◽  
Leukemia Virus ◽  
Herd Size ◽  
Cross Sectional ◽  
Herd Level ◽  
Apparent Prevalence ◽  
Observational Study Design ◽  
Epidemiologic Features

Objective. To estimate current US herd-level and animal-level prevalence of bovine leukemia virus (BLV) in dairy cows and characterize epidemiologic features. Design. Cross-sectional observational study design and survey. Animals. 4120 dairy cows from 103 commercial dairy herds in 11 states across the US. Procedures. Milk samples were collected from dairy cows through routine commercial sampling and tested for anti-BLV antibodies by antibody capture ELISA. Based on the ELISA results of a sample of an average of 40 cows per herd, within-herd apparent prevalence (AP) was estimated by a directly standardized method and by a lactation-weighted method for each herd. Within-herd AP estimates were summarized to give estimates of US herd-level and animal-level AP. Differences in AP by lactation, region, state, breed, and herd size were examined to characterize basic epidemiologic features of BLV infection. Results. 94.2% of herds had at least one BLV antibody positive cow detected. The average within-herd standardized AP was 46.5%. Lactation-specific AP increased with increasing lactation number, from 29.7% in first lactation cows to 58.9% in 4th and greater lactation cows. Significant differences were not observed based on region, state, breed, or herd size. Conclusions and Clinical Relevance. These results are consistent with a historical trend of increasing prevalence of BLV among US dairy cattle. Given the findings of other studies on the negative impacts of BLV infection on milk production and cow longevity, these findings are clinically relevant for veterinarians counseling dairy clients on the risks of BLV to their herds.

Herd-level risk factors for infection with bovine leukemia virus in Canadian dairy herds

2015 ◽  
Vol 119 (3-4) ◽  
pp. 105-113 ◽  
Author(s):  
Omid Nekouei ◽  
John VanLeeuwen ◽  
Javier Sanchez ◽  
David Kelton ◽  
Ashwani Tiwari ◽  
...  
Keyword(s):  
Risk Factors ◽  
Bovine Leukemia Virus ◽  
Leukemia Virus ◽  
Dairy Herds ◽  
Herd Level

scholarly journals Bayesian Estimation of the True Seroprevalence and Risk Factor Analysis of Bovine Leukemia Virus Infection in Pakistan

Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1404
Author(s):  
Ali Sakhawat ◽  
Marzena Rola-Łuszczak ◽  
Zbigniew Osiński ◽  
Nazia Bibi ◽  
Jacek Kuźmak
Keyword(s):  
Risk Factor ◽  
Dairy Cattle ◽  
Bovine Leukemia Virus ◽  
Water Buffalo ◽  
Leukemia Virus ◽  
Credible Interval ◽  
Indigenous Cattle ◽  
Herd Level ◽  
Exotic Breed ◽  
Posterior Estimate

The objective of this study was to determine the true seroprevalence of bovine leukemia virus (BLV) infection in dairy cattle from Pakistan at the animal and herd-level. We tested 1380 dairy cattle from 451 herds and 92 water buffalo. The sera were tested by ELISA and the results were analyzed using Bayesian inference. The median posterior estimate of the herd level true BLV prevalence was 1.4%, with a 95% credible interval (CI) 0.7–3.1, whereas the median posterior estimate of the within-farm true seroprevalence was 3.8% with a 95% CI 2.8–4.8. All 92 sera collected from water buffalo were negative. Several risk factors potentially associated with seropositivity to BLV infections in Pakistan were analyzed using logistic regression model based on calculation of an odds ratio (OR). The study showed an association between seropositivity and medium herd (≥50) size (OR = 23.57, 95% CI: 3.01–103.48). Common housing of indigenous cattle with exotic-breed cattle (OR = 0.67, 95% CI: 06–2.35) or housing indigenous or their crossbred cattle with exotic-breed cattle (OR = 0.95, 95% CI: 0.14–3.01) had no effect on the BLV seroprevalence. Similarly, common housing of cattle and water buffalo was not risk factor for increased BLV seropositivity (OR = 27.10, 95% CI: 0.63–119.34).

Large-scale study of herd-level risk factors for bovine brucellosis in Brazil

Acta Tropica ◽  
2016 ◽  
Vol 164 ◽  
pp. 226-232 ◽  
Author(s):  
Ana Lourdes Arrais de Alencar Mota ◽  
Fernando Ferreira ◽  
José Soares Ferreira Neto ◽  
Ricardo Augusto Dias ◽  
Marcos Amaku ◽  
...  
Keyword(s):  
Risk Factors ◽  
Large Scale ◽  
Bovine Brucellosis ◽  
Herd Level ◽  
Large Scale Study

Recurrent Primary Sclerosing Cholangitis: Current Understanding, Management, and Future Directions

2021 ◽  
Author(s):  
Kristel K. Leung ◽  
Maya Deeb ◽  
Sandra E. Fischer ◽  
Aliya Gulamhusein
Keyword(s):  
Risk Factors ◽  
Primary Sclerosing Cholangitis ◽  
Sclerosing Cholangitis ◽  
Large Scale ◽  
Related Factors ◽  
Future Directions ◽  
History Of ◽  
Inflammatory Bowel ◽  
Specific Factors ◽  
Associated Risk Factors

AbstractPatients with primary sclerosing cholangitis (PSC) constitute 5 to 15% of patients listed for liver transplantation worldwide. Although post-transplant outcomes are favorable, recurrent PSC (rPSC) occurs in an important subset of patients, with higher prevalence rates reported with increasing time from transplant. Given its association with poor graft outcomes and risk of retransplant, effort has been made to understand rPSC, its pathophysiology, and risk factors. This review covers these facets of rPSC and focuses on implicated risk factors including pretransplant recipient characteristics, inflammatory bowel-disease-related factors, and donor-specific and transplant-specific factors. Confirming a diagnosis of rPSC requires thoughtful consideration of alternative etiologies so as to ensure confidence in diagnosis, management, subsequent risk assessment, and counseling for patients. Unfortunately, no cure exists for rPSC; however, future large-scale efforts are underway to better characterize the natural history of rPSC and its associated risk factors with hopes of identifying potential key targets for novel therapies.

Molecular detection and characterization of genotype 1 bovine leukemia virus from beef cattle in the traditional sector in Zambia

2019 ◽  
Vol 164 (10) ◽  
pp. 2531-2536 ◽  
Author(s):  
Mundia M. Phiri ◽  
Evans Kaimoyo ◽  
Katendi Changula ◽  
Isaac Silwamba ◽  
Herman M. Chambaro ◽  
...  
Keyword(s):  
Beef Cattle ◽  
Bovine Leukemia Virus ◽  
Molecular Detection ◽  
Leukemia Virus ◽  
Genotype 1 ◽  
Traditional Sector
Sign in / Sign up

Export Citation Format

Share Document