Herd-Level Risk Factors for Lameness, Leg Injuries, Thin Body Condition and Mastitis on Algerian Dairy Farms

This present study aims to investigate the relationship of herd characteristics and management practices with the prevalence of clinical and severe lameness, hock and knee injuries, thin cows, and mastitis at the herd level on Algerian dairy farms. Altogether 1210 dairy cows from 107 farms were examined and the clinical aspects related to studied affections were recorded. Multivariable regression models were built to analyse the relationship between the risk factors and the occurrence of health indicators. Overlay, the health outcomes were multifactorial, with pasture access (P < 0.001), scraping frequency (P < 0.01), and floor regularity (P = 0.05) as the main factors causing lameness. Factors associated with both hock and knee injuries (score ≥ 2) were lower cow number (P < 0.01), more days spent on pasture (P < 0.001), and poorer straw amount for bedding (P < 0.001). Some farming practice, in particular, providing proper amount of concentrate feeds (P < 0.001), higher scraping frequency (P < 0.01), thicker bedding (P < 0.001), and having younger dairy cows (P = 0.058), were associated with a lower within-herd prevalence of thin cows. While, more days on pasture increased the percentage of under-conditioned cows (P < 0.01). The inadequate hygienic conditions of the floor (P < 0.001), improper milking procedures (P < 0.05), and shorter dry period (P < 0.05) increased the clinical mastitis occurrence. Our results highlighted the specific management practices responsible for increasing health risks and provided useful information for the farmers and veterinarians to make preventive and controlling strategies for lameness, leg injuries, low body condition and mastitis on dairy farms.