title: Lameness Prevalence and Risk Factors in Large Dairy Farms in Upstate New York. Model Development for the Prediction of Claw Horn Disruption Lesions.
abstract: The main objectives of this prospective cohort study were a) to describe lameness prevalence at drying off in large high producing New York State herds based on visual locomotion score (VLS) and identify potential cow and herd level risk factors, and b) to develop a model that will predict the probability of a cow developing claw horn disruption lesions (CHDL) in the subsequent lactation using cow level variables collected at drying off and/or available from farm management software. Data were collected from 23 large commercial dairy farms located in upstate New York. A total of 7,687 dry cows, that were less than 265 days in gestation, were enrolled in the study. Farms were visited between May 2012 and March 2013, and cows were assessed for body condition score (BCS) and VLS. Data on the CHDL events recorded by the farm employees were extracted from the Dairy-Comp 305 database, as well as information regarding the studied cows' health events, milk production, and reproductive records throughout the previous and subsequent lactation period. Univariable analyses and mixed multivariable logistic regression models were used to analyse the data at the cow level. The overall average prevalence of lameness (VLS > 2) at drying off was 14%. Lactation group, previous CHDL, mature equivalent 305-d milk yield (ME305), season, BCS at drying off and sire PTA for strength were all significantly associated with lameness at the drying off (cow-level). Lameness at drying off was associated with CHDL incidence in the subsequent lactation, as well as lactation group, previous CHDL and ME305. These risk factors for CHDL in the subsequent lactation were included in our predictive model and adjusted predicted probabilities for CHDL were calculated for all studied cows. ROC analysis identified an optimum cut-off point for these probabilities and using this cut-off point we could predict CHDL incidence in the subsequent lactation with an overall specificity of 75% and sensitivity of 59%. Using this approach, we would have detected 33% of the studied population as being at risk, eventually identifying 59% of future CHDL cases. Our predictive model could help dairy producers focusing their efforts on CHDL reduction by implementing aggressive preventive measures for high risk cows.
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States of America.
authors.forename: Carla
authors.initials: C
authors.lastname: Foditsch
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States of America.|Department of Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Cheshire, United Kingdom.
authors.forename: Georgios
authors.initials: G
authors.lastname: Oikonomou
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States of America.
authors.forename: Vinícius Silva
authors.initials: VS
authors.lastname: Machado
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States of America.
authors.forename: Marcela Luccas
authors.initials: ML
authors.lastname: Bicalho
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States of America.
authors.forename: Erika Korzune
authors.initials: EK
authors.lastname: Ganda
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States of America.
authors.forename: Svetlana Ferreira
authors.initials: SF
authors.lastname: Lima
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States of America.
authors.forename: Rodolfo
authors.initials: R
authors.lastname: Rossi
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States of America.
authors.forename: Bruno Leonardo
authors.initials: BL
authors.lastname: Ribeiro
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States of America.
authors.forename: Arieli
authors.initials: A
authors.lastname: Kussler
authors.affiliation: Department of Population Medicine and Diagnostic Sciences, College of Veterinary Medicine, Cornell University, Ithaca, NY, United States of America.
authors.forename: Rodrigo Carvalho
authors.initials: RC
authors.lastname: Bicalho
mesh_terms: D000375:Aging; D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology*; D015331:Cohort Studies; D003612:Dairying; D005684:Gait / Q000502:physiology; D006724:Hoof and Claw / Q000473:pathology*; D006733:Horns / Q000473:pathology*; D007794:Lameness, Animal / Q000453:epidemiology*; D009518:New York / Q000453:epidemiology; D011446:Prospective Studies; D012372:ROC Curve; D012307:Risk Factors