[Teil 1: Mastitis und Lahmheit - Part 1: Mastitis and lameness]

Production-limiting diseases such as mastitis and lameness are among the most common causes of early culling in dairy cows worldwide. The aim of this systematic literature review was to analyze the effects of these 2 disease complexes on culling risk in dairy cows based on scientific evidence.

The literature search was conducted in accordance with PRISMA guidelines using the databases PubMed, CABI Abstracts, and Web of Science, covering publications from 2000-2024. For each part of the study, the results were analyzed qualitatively and presented descriptively as forest plots.

A total of 28 studies on mastitis and 11 studies on lameness were included. The highest relative mortality risk (4.5) in primiparous cows was associated with clinical mastitis caused by Klebsiella spp.; the highest relative risk of premature culling (10.4) was associated with clinical mastitis caused by Trueperella pyogenes. The relative risk of premature culling for Staphylococcus aureus-related clinical mastitis up to 62 days in milk was 1.2 and increased to 5.4 thereafter. Cows without subclinical mastitis had only half the risk of culling compared to cows with a cell count>200,000 cells/ml in the first month of lactation. With regard to lameness, the relative risk of premature culling was between 1.0 and 2.0 and was therefore only slightly increased. Only deep claw infections in conjunction with thin soles, horn cracks and interdigital hyperplasia were found to have a high risk of culling (6.9).

Mastitis and lameness in various forms significantly increase the risk of early culling of dairy cows. Due to their high clinical and economic relevance, preventive measures relating to udder and hoof health, as well as integrated veterinary herd management, should be an integral part of herd management.

Targeted reduction in the incidence of mastitis and lameness can significantly contribute to prolonging the productive lifespan of dairy cows, improving animal welfare, and enhancing the economic efficiency of dairy farming operations. With respect to premature culling, the prevention of clinical udder inflammation is crucial.