Seasonal and group effects on dairy cow behavior in large yards

Abstract

In mechanized modern dairy facilities with competitive environments, monitoring behavior provides opportunities to manipulate and optimize the nutritional, health, and social status of high-merit cows. The objective of the current study was to determine seasonal and cow group effects on the eating, ruminating, standing, and lying behaviors of dairy cows in large yards. Seasonal data on various behaviors of lactating cows in different production and lactation stages were collected continuously for 26 months, from December 2006 through February 2008. The herd had approximately 3000 dairy cattle housed in groups within specific yards. A total of 415 multiparous high-producing cows (MH), 166 multiparous medium-producing cows (MM), 166 multiparous low-producing cows (ML), 165 primiparous high-producing cows (PH), 83 fresh cows (FC), 82 fresh heifers (FH), and 82 cows with high milk somatic cell count (HSCC) were monitored. Seasonal eating, ruminating, standing, and lying behaviors were recorded by 4 trained individuals at 1000 hours every week, on 4 days per week. Each activity was expressed as the proportion of cows exhibiting the activity relative to the total number of cows in the yard. Feed was delivered 6 times daily, 4 times as TMR at 0600, 1030, 1300, and 1800, just after milking and twice as alfalfa hay at nighttime. Across all groups, a greater proportion of cows were observed eating during winter (25.7%) than during spring (17.1%), summer (15.4%), and autumn (14.5%). The proportion of cows neither eating nor ruminating was lower in winter (48.1%) than in summer (58.9%) and autumn (58.6%), but similar to spring (53.7%). A greater proportion of cows in the PH (24.6%) and ML (21.3%) groups were observed eating, compared with the MM (15.2%), MH (16.6%), and FC (12.6%) groups. Lying was observed significantly more often in the FC (71%), MM (69.6%), HSCC (65.3%), and MH (64%) groups than in FH (54%), ML (55.7%), and PH (55.7%) groups. A greater proportion of cows were observed ruminating in the MM (31.7%), FC (31.3%), HSCC (28.7%), PH (27.2%), and MH (26.7%) groups, when compared to the FH (20.5%) and ML (22.9%) groups. The HSCC cows were less active in eating and more active in lying than the PH and ML groups. With the remarkably large sample size and prolonged study period, these findings reveal the determining effects of season alongside age, lactation stage, productivity, and-to some extent-mastitis on the eating, ruminating, and resting behaviors of dairy cows in large yard houses.