TY - JOUR

T1 - Bovine Digital Dermatitis

T2 - Treponema spp. on trimming equipment and chutes – effect of washing and disinfection

AU - Ahlén, Lina

AU - Holmøy, Ingrid Hunter

AU - Sogstad, Åse Margrethe

AU - Jensen, Tim Kåre

AU - Frosth, Sara

AU - Rosander, Anna

AU - Fjeldaas, Terje

N1 - Publisher Copyright: © The Author(s) 2024.

PY - 2024/12

Y1 - 2024/12

N2 - Background: Digital dermatitis (DD) is a contagious bovine foot disease causing reduced animal welfare and negative economic consequences for the farmer. Treponema spp. are the most important causative agents. Studies indicate that trimming equipment can transfer DD-associated treponemes between cows. The aim of this observational study in 22 DD-positive Norwegian dairy herds was to investigate the risk of transferring Treponema spp. with trimming equipment and chutes after claw trimming, and after washing and disinfection. Swabs from the trimming equipment and chutes were collected from nine different locations, at five different time points. Bacterial DNA was extracted from 647 swabs and analysed by qPCR for Treponema spp. In addition, 172 swabs taken immediately after trimming, were analysed by a multiplex qPCR targeting T. phagedenis, T. pedis and T. medium/vincentii. Biopsy sampling from DD lesions was performed on cows in the same herds during trimming. Altogether 109 biopsies were analysed by FISH for confirmation of the DD diagnosis and identification of Treponema phylotypes (PTs). Results: High numbers of Treponema spp. were detected from all nine locations on the trimming equipment and chutes immediately after trimming, and T. phagedenis was detected on two or more locations in all but two herds, 1 and 19. There was a decline in the amount of Treponema spp. after washing and disinfection. The belly belt, the cuff, and the footrest on the chute had the highest proportion of positive samples after disinfection. The belly belt had the highest copy numbers of all nine locations (median = 7.9, max = 545.1). No Treponema spp. was detected on the hoof knives after disinfection. Treponema phagedenis, T. pedis, and Treponema phylotype 3 (T. refringens) were detected by FISH analysis of the biopsies. Treponema phagedenis was detected in biopsies from all herds except 1 and 19. Conclusion: This study shows that DD-associated Treponema spp. were present on the trimming equipment and chutes after trimming cows in DD-positive herds. Washing and disinfection reduced the load of Treponema spp. However, large differences in Treponema spp. between different locations were documented. High copy numbers on the grinder and the chute after disinfection, indicates that sufficient cleaning and disinfection of these locations is difficult, and that passive transfer of DD-associated treponemes (viable or not) is possible.

AB - Background: Digital dermatitis (DD) is a contagious bovine foot disease causing reduced animal welfare and negative economic consequences for the farmer. Treponema spp. are the most important causative agents. Studies indicate that trimming equipment can transfer DD-associated treponemes between cows. The aim of this observational study in 22 DD-positive Norwegian dairy herds was to investigate the risk of transferring Treponema spp. with trimming equipment and chutes after claw trimming, and after washing and disinfection. Swabs from the trimming equipment and chutes were collected from nine different locations, at five different time points. Bacterial DNA was extracted from 647 swabs and analysed by qPCR for Treponema spp. In addition, 172 swabs taken immediately after trimming, were analysed by a multiplex qPCR targeting T. phagedenis, T. pedis and T. medium/vincentii. Biopsy sampling from DD lesions was performed on cows in the same herds during trimming. Altogether 109 biopsies were analysed by FISH for confirmation of the DD diagnosis and identification of Treponema phylotypes (PTs). Results: High numbers of Treponema spp. were detected from all nine locations on the trimming equipment and chutes immediately after trimming, and T. phagedenis was detected on two or more locations in all but two herds, 1 and 19. There was a decline in the amount of Treponema spp. after washing and disinfection. The belly belt, the cuff, and the footrest on the chute had the highest proportion of positive samples after disinfection. The belly belt had the highest copy numbers of all nine locations (median = 7.9, max = 545.1). No Treponema spp. was detected on the hoof knives after disinfection. Treponema phagedenis, T. pedis, and Treponema phylotype 3 (T. refringens) were detected by FISH analysis of the biopsies. Treponema phagedenis was detected in biopsies from all herds except 1 and 19. Conclusion: This study shows that DD-associated Treponema spp. were present on the trimming equipment and chutes after trimming cows in DD-positive herds. Washing and disinfection reduced the load of Treponema spp. However, large differences in Treponema spp. between different locations were documented. High copy numbers on the grinder and the chute after disinfection, indicates that sufficient cleaning and disinfection of these locations is difficult, and that passive transfer of DD-associated treponemes (viable or not) is possible.

KW - Biopsies

KW - Claw trimming

KW - FISH

KW - Passive transfer

KW - qPCR

KW - Swabs

UR - http://www.scopus.com/inward/record.url?scp=85196431560&partnerID=8YFLogxK

U2 - 10.1186/s12917-024-03941-z

DO - 10.1186/s12917-024-03941-z

M3 - Journal article

C2 - 38890626

AN - SCOPUS:85196431560

VL - 20

JO - B M C Veterinary Research

JF - B M C Veterinary Research

SN - 1746-6148

IS - 1

M1 - 261

ER -