Comparison of milk yield in dairy cows with different degrees of lameness.
OBJECTIVE
To compare milk yield among cows classified as nonlame, moderately lame, and lame and to examine the relationship between severity of lameness and milk yield in cows classified as lame during the first 100 days after parturition.


METHODS
Longitudinal study.


METHODS
465 Holstein cows.


METHODS
Cows were examined weekly during the first 100 days after parturition and assigned a lameness score by use of a 6-point locomotion scoring system (ie, 0 to 5). Milk yield was compared among cows classified as nonlame, moderately lame, and lame. Among cows classified as lame (locomotion score > or = 4), milk yield was compared for cows with low, medium, and high cumulative locomotion scores. Cows classified as lame were further examined on a tilt table for diagnosis and treatment of lameness.


RESULTS
84 (18%), 212 (46%), and 169 (36%) cows were classified as nonlame, moderately lame, and lame, respectively. Among cows in their second or later lactations, milk yield in lame cows was significantly lower than that in moderately lame and nonlame cows. In addition, among cows classified as lame, milk yield was significantly lower in cows with high locomotion scores during the first 100 days after parturition, compared with cows with low scores. Most (58%) cows classified as lame had laminitis.


CONCLUSIONS
Results indicate a linear relationship between increasing degree of lameness and decreasing milk yield among cows in their second or later lactations. The locomotion scoring system used in this study may be a useful management tool that veterinarians and dairy farmers could adopt for early detection of lameness in dairy cows.
Hernandez
Jorge A
JA
Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32610-0136, USA.
Garbarino
Eduardo J
EJ
Shearer
Jan K
JK
Risco
Carlos A
CA
Thatcher
William W
WW
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000503:physiopathology*; D005260:Female; D005534:Foot Diseases / Q000503:physiopathology / Q000662:veterinary*; D006724:Hoof and Claw / Q000473:pathology; D007774:Lactation / Q000502:physiology; D007794:Lameness, Animal / Q000145:classification / Q000503:physiopathology*; D008137:Longitudinal Studies; D008892:Milk / Q000378:metabolism*; D049590:Postpartum Period; D012720:Severity of Illness Index