Short communication: Informative value of an ELISA applied to bulk tank milk to assess within-herd prevalence of digital dermatitis in dairy herds.
J Dairy Sci
; 104(1): 963-968, 2021 Jan.
Article
em En
| MEDLINE
| ID: mdl-33162093
ABSTRACT
The objective of this study was to assess whether an antibody ELISA applied to bulk tank milk (BTM) could be used to accurately estimate within-herd prevalence of digital dermatitis (DD). The ELISA was designed for the detection of antibodies against Treponema phagedenis-like strain V1 (PrrA antigen). The hind feet of all lactating cows from 40 commercial French dairy herds with a history of DD were scored by an observer in the milking parlor, using the 4 M-stage system. After milking, a BTM sample was collected and tested for anti-Treponema phagedenis-like antibodies using the antibody ELISA. Within-herd DD prevalence at the cow level was determined using 2 different approaches (1) having DD lesion on at least 1 hind foot (Prev; prevalence of affected cows), and (2) having an M1 or M2 lesion on at least 1 hind foot (PrevA; prevalence of cows affected by DD in an active stage). Receiver operating characteristic analysis was used to determine both optimal within-herd DD prevalence and BTM sample to positive (S/P) ratio cut-off values. Two optimal cut-off values were identified. Herds with an S/P ratio of BTM ≤0.2 had a Prev ≤10% (sensitivity = 0.97, specificity = 1), whereas herds with an S/P ratio of BTM >0.38 had a Prev >40% (sensitivity = 0.94, specificity = 0.86). In the same way but with a slightly lower specificity, an S/P ratio >0.38 corresponds also to a PrevA >18% (sensitivity = 0.92, specificity = 0.70). The BTM antibody ELISA shows great promise for screening purposes during DD management programs.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Treponema
/
Infecções por Treponema
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Ensaio de Imunoadsorção Enzimática
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Doenças dos Bovinos
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Leite
/
Dermatite Digital
Tipo de estudo:
Diagnostic_studies
/
Evaluation_studies
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Prevalence_studies
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Prognostic_studies
/
Risk_factors_studies
Limite:
Animals
Idioma:
En
Revista:
J Dairy Sci
Ano de publicação:
2021
Tipo de documento:
Article