Economic models to estimate changes in herd sustainability and structure associated with clinical cure failure of...

This study aimed to evaluate the economic and environmental impacts of clinical cure failure of metritis in dairy herds using a dynamic Markov chain model. Metritis incidence was set at 25% of postpartum cows, with 3 scenarios simulated over a 10-yr horizon: base (no metritis), cured (all metritis cases cured), and not cured (no cases cured). Herd size was constrained to 900 to 1,000 milking cows, and all metritis cases were treated with ceftiofur crystalline-free acid. Outputs from year 10 (steady-state herd) were used for comparison. Total herd population was greatest in the not cured scenario, driven by a higher proportion of heifers retained for replacement. Although the number of lactating and dry cows remained similar across scenarios (constrained by our model), milk yield declined from 42 kg/d (base) to 40 kg/d (cured) and 37 kg/d (not cured). Heifer pregnancy rate did not differ among scenarios, whereas cow 22-d pregnancy rate decreased from 25% (base) to 22% (cured) and 20% (not cured). Cow culling was highest in the not cured scenario. Milk revenue and income over feed cost declined with increasing disease severity, whereas operating, reproductive, and replacement costs increased. Overall farm profit decreased from $1.30 million ($1,225/cow) in the base scenario to $1.16 million ($1,067/cow) in the cured and $0.92 million ($838/cow) in the not cured scenario. Methane, nitrogen, and phosphorus excretion per liter of milk increased progressively from the base to the not cured scenario. The estimated cost per case of metritis increased from $460 in the cured scenario to $1,403 when cure failed. These results demonstrate that clinical cure failure of metritis substantially reduces herd productivity, profitability, and environmental efficiency, emphasizing the importance of metritis prevention and successful clinical resolution.