Type

Journal Article

Authors

Simon John More
E. K. B. Richardson

Subjects

Veterinary

Topics
pre clinical somatic cell count dairy farm milk yield clinical symtoms case control johne s disease clinical symptoms disease impacts irish dairy herd negative impact culling dairy cows

Direct and indirect effects of johne's disease on farm and animal productivity in an irish dairy herd (2009)

Abstract Johne's disease (JD) is caused by infection with the organism Mycobacterium avium spp. paratuberculosis, leading to chronic diarrhoea and ill thrift in adult cattle. JD is considered to adversely affect farm performance and profitability. This retrospective case study was undertaken on a single commercial dairy herd in the south west of Ireland. Animal production records were interrogated to assess the effect of JD on milk yield (total kg per lactation), somatic cell count (the geometric mean over the lactation), reasons for culling, cull price and changes in herd parity structure over time. JD groups were defined using clinical signs and test results. One control animal was matched to each case animal on parity number and year. Specific lactations (clinical, pre-clinical and test-positive only) from 1994 to 2004 were compared between JD case and control cows. A significantly lower milk yield (1259.3 kg/lactation) was noted from cows with clinical JD in comparison to their matched control group. Clinical animals had an average cull price of €516 less than animals culled without signs of clinical disease. In contrast, little effect was noted for sub-clinical infections. These direct effects of JD infections, in combination with increased culling for infertility and increasing replacement rates, had a negative impact on farm production. Results from this study provide preliminary information regarding the effects of JD status on both herd and animal-level performance in Ireland.
Collections Ireland -> University College Dublin -> Veterinary Medicine Research Collection (superseded in 2015)
Ireland -> Teagasc -> Teagasc publications in Biomed Central
Ireland -> Teagasc -> Other Teagasc Research
Ireland -> University College Dublin -> Institutes and Centres
Ireland -> University College Dublin -> College of Agriculture, Food Science and Veterinary Medicine (superseded in 2015)
Ireland -> University College Dublin -> School of Veterinary Medicine (superseded in 2015)
Ireland -> University College Dublin -> Centre for Veterinary Epidemiology and Risk Analysis (CVERA)
Ireland -> University College Dublin -> CVERA Research Collection
Ireland -> Teagasc -> Other Teagasc Research
Ireland -> Teagasc -> Teagasc publications in Biomed Central

Full list of authors on original publication

Simon John More, E. K. B. Richardson

Experts in our system

1
S J More
University College Dublin
Total Publications: 171