Making tiestalls more comfortable: Ⅳ. Increasing stall bed length and decreasing manger wall height to heal injuries and increase lying time in dairy cows housed in deep-bedded tiestalls

摘要

Poor stall configuration can negatively affect cowwelfare by impairing lying behavior and leading toinjuries in dairy cows. The comfort of the stall bedin tiestalls is affected by the material components ofthe stall bed (stall base and bedding), but also by theamount of space provided. The amount of space cowsare able to access lengthwise in a tiestall is determinedby the stall bed length and the height of the mangerwall (the front limit of the stall bed), which can limitaccess into the space available at the front of the stall.This project aimed to maximize cow comfort in deepbeddedtiestalls by investigating the combined effectof increased bed length and decreased manger wallheight in a crossover experiment (2 periods with 1 wkhabituation + 6 wk data collection). Two rows of 12tiestalls were modified (n = 24 cows). Each row was adifferent length, short (178 cm; length commonly foundin Quebec) or long (188 cm), and cows remained onthe same row (same stall bed length) for the entireexperiment. In each row, there were 6 stalls of eachmanger wall height treatment: high (20 cm, upper limitrecommended) or low (5 cm). During period 2, cowsswitched manger wall height treatments. A 7.6-cm-deepstraw bedding layer was added to all stalls by adding abedding keeper to the ends of stalls. All initially injuredlocations healed over the 14-wk study, and 2 patterns ofhealing emerged. Improvement in hock injury (lateraltarsal and calcanei) was observed from wk 1 to 6 for alltreatments. A plateau in injury severity score reductionwas observed in period 2 for the hock (lateral, dorsal,and medial calcanei), anatomical knee, carpal joints(front knees), and proximal and medial neck, which waslikely the result of the insensitivity of the injury scoringscheme rather than healing not occurring. Cows in longstalls were found to spend more time lying (14.1 vs.13.3 h/d) and had longer lying bouts than cows in shortstalls (74.1 vs. 52.9 min/bout). Manger wall height didnot affect injury or lying time, but may affect how cowsposition themselves while lying. Higher lying times inour study were comparable to those reported in deepbeddedloose pens, indicating that cows with more bedding,especially those in long stalls, were more comfortable.Our results suggest that deep-bedded straw stallswith bedding keepers have the potential to be beneficialto cow comfort on tiestall farms.