Short communication: effect of alley floor cleanliness on free-stall and udder hygiene

The objective was to evaluate the effect of alley floor cleanliness on the hygiene of the free-stalls and udder and teats of cows. Mechanical scrapers were used on rubber-slatted floors to improve the cleanliness of the alley floor. Two sections containing 21 cows each were evaluated once weekly for a period of 3 wk. One section had scrapers on the rubber-slatted floor in the alleys and the other section did not. The scrapers ran 12 and 7 times/d in the free-stall alley and feed alley, respectively. Manure accumulation in the alleys at approximately 2 h after the scrapers had run was less in the section with the scraper than in that without the scraper. Differences between sections with and without scrapers were found in the sites close to the wall in the feed alley, and immediately behind the free-stalls in the free-stall alley. In the section without scrapers, manure accumulation was greater in the free-stall alley than in the feed alley. Manure contamination of the area in the free-stalls where the udder normally comes in contact with the free-stall floor was significantly reduced from 29.1 to 17.9 +/- 2.4 g of dry matter when the alley floor was kept clean by the use of scrapers. The hygiene scores of the dirtiness of udders were reduced from 25.8 +/- 1.7 to 18.9 +/- 1.6, and those of the teats from 37.9 +/- 2.3 to 24.2 +/- 2.3 in the section with scrapers and cleaner alley floor compared with the section without scrapers. The scrapers greatly improved the hygiene on the rubber-slatted alley floor. The cleaner alley floor had a positive effect on the cleanliness of the free-stalls and the udder and teats of the cows.