Effect of lameness on daily milk yield in dairy cow

Abstract

Being aware of the impact of lameness on milk production is necessary to encourage farmers to pay more attention to this issue. Therefore, we need evidence that presents the production loss due to lameness. This can be applied to make the farmers realize the importance of lameness. This study aims to examine the impact of lameness on daily milk yield based on data obtained from cow level in a large dairy farm with 2 units in Thailand. The crossbred Holstein Friesian cows were evaluated for the degree of lameness by locomotion score (LS) monthly for 8 consecutive months. Cows were separated into non-lameness (LS1), subclinical lameness (LS2-3) and clinical lameness (LS4-5). The cows’ data which included lactation number, days in milk, lameness, mastitis, metritis, other medical records and milk production in kg/day/cow was collected by Dairy Champ software. The data analysis was performed by univariable analysis at P<0.1 without correlation with other variables more than 30% and multivariable analysis was performed simultaneously. Variables associated with daily milk yield were examined for interaction at P<0.05. The predictability of the equation was examined. 305 days of milk production was simulated by using Monte-Carlo technique. The 856 data sets from 184 cows were recorded for daily milk yield and LS. The non-lameness, subclinical and clinical lameness groups were 49.6, 43.7 and 6.7%, respectively. The average of 305 days milk yield of the non-lameness group in unit 1 and 2 was 6,426.9 ± 1,544.8 and 4,651.6 ± 1,420.1 kg, respectively. The simulation data showed a decrease in 305 days of milk yield (1,266.2 ± 467.5 kg) in cows where lameness occurred throughout the 1st lactation when compared with a healthy cow. The clinical and subclinical lameness in the first three months of the lactation period reduced the daily milk yield by 1.2 ± 0.5 and 0.2 ± 0.6 kg, respectively. In addition, the occurrence of clinical and subclinical lameness with clinical mastitis reduced the daily milk yield by 1.6 ± 0.9 and 0.5 ± 1.0 kg, respectively. This study showed evidence of milk loss caused by lameness. This can motivate farmers to take action on lameness and preventive measures should be planned to reduce the production loss in the farm.