Short communication: Use of the Clegg hammer measure as an indicator of stall-surface compressibility in tie stall housing and its relationship with stall comfort

摘要

Stall base and stall surface (i.e., with or withoutbedding) are key risk factors in cow comfort in dairyherds. In Canada, rubber mats, concrete floors, andmattresses are the most common stall bases used intie-stall systems. Straw, wood shavings, and sand, atvariable depths, are the most commonly used type ofbedding. The Clegg hammer (Clegg Impact Soil TesterHammer; Lafayette Instrument Company, Lafayette,IN) is a tool used by engineers to test the compressibilityof pavement or golf course surfaces. Recently, thistool has also been used to measure the compressibilityof the stall surface on freestall dairy farms. A total of32 tie-stall dairy herds were selected in Québec to testthe usefulness of the Clegg hammer as a tool to assessstall surface compressibility in tie-stall housing. Thisstudy had 2 main objectives: (1) identify the locationand the number of measurements needed to obtaina stable indicator of compressibility, and (2) identifydifferences in the compressibility of the stall surfacedepending on the stall base and bedding depth. Oneach farm, we tested the compressibility of 10 stalls. Nosignificant differences were found between the front andthe back of the stall for the location of the Clegg hammermeasures. The differences in readings of the Clegghammer were nonsignificant after the third measuretaken at the same location, meaning that 3 measuresare sufficient at one location to obtain a compressibilitymeasure. Significant differences were found among thedifferent stall base and surface combinations tested.Rubber mats were less compressible than mattresses.When a large quantity of bedding (>7.5 cm) was addedon top of rubber mats, the compressibility results wereequal to those of mattresses ≥10 yr old without bedding.To appropriately test the compressibility of stallsurface in tie-stall farms, we recommend measuring thecompressibility of the stall base on its own and withthe usual amount of bedding used on the farm. Ourstudy establishes that both stall base and surface affectcompressibility, and that a large quantity of beddinghelps increase the compressibility of the bed, especiallyon a harder stall base.