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Associations of Stall Design, Behavior, and Hygiene of Lactating Dairy Cows
Free stall standing behavior is typically indexed to improve cow and stall hygiene using stall designs that are often restrictive to the cow. The objective of this observational study was to determine the association of stall design, cow hygiene, and lying behavior in lactating Holstein dairy cows (n= 23; parity = 3.0±1.3; mean ± SD). Cows were part of a group of 40±3 cows, housed in a free-stall barn with 52 free stalls (head-to-head), and designed for free cow traffic to an automated milking system. Each stall was 1.93m long (from rear of curb to brisket board), 1.22m wide, and the stationary neck rail was 1.26m above the stall bedding surface (water mattress bedded with wood shavings), and 1.91m from the rear curb. Cows were observed for 4, 2-wk periods. During periods 1 and 3, a swinging PVC neck guard (located 0.92m from the base of the stall and 2.22m from the curb) was installed in the free stalls. Cows were hygiene scored (flank, udder, and lower leg; scale of 1 = very clean to 4 = very dirty) on the last 7 d of each period. Stalls were hygiene scored using a grid system (# contaminated 0.15×0.15 m squares in a 1.20×1.60 m grid). Electronic data loggers were used monitor lying behavior. Data were analyzed in multivariable mixed-effect regression models. Lying duration tended (P=0.1) to decrease when cows were kept with the neck guard (-0.6 h/d; SE=0.4), and was decreased (P<0.05) in primiparous cows (-1.2 h/d; SE=0.5), with higher production (-0.07×kg/d; SE=0.03), and when stalls were dirtier (-9.4×stall hygiene score; SE=4.5). Flank hygiene was worse when cows were kept with the neck guard (P=0.001), in multiparous cows (P=0.04), when stalls were dirtier (P=0.002), and tended to be worse when cows spend less time lying down (P=0.1). Udder hygiene was worse in multiparous cows (P=0.03), when cows spend less time lying down (P=0.002), and tended to be worse when stalls were dirtier (P=0.06). Lower leg hygiene was worse in multiparous cows (P=0.006), when cows spend less time lying down (P=0.04), and tended to be worse in earlier lactation cows (P=0.07). In summary, these results show that cow lying duration may be negatively impacted when free-stall design imposes restrictions on usage and when stalls are dirty. Further, cow hygiene is affected by lying behavior patterns of cows and by the cleanliness of the cow’s environment.
Keywords: hygiene, behavior, stall design