Graduate Student Literature Review: Organic dairy cattle longevity and economic implications-Contemporary perspectives.

Although conventional production systems have been studied extensively, limited research exists on the longevity of organically raised dairy cows. The objective was to discuss the factors affecting dairy cattle longevity and to conduct an economic assessment for prolonged longevity of organic dairy cattle. A dynamic programming tool was adopted for a typical organic and conventional dairy farm in Texas to determine optimal replacement decisions for organic dairy cattle based on the retention pay-off (RPO) value. The model included milk price, calf value, replacement heifer costs, veterinary expenses, financial losses at disposal, insemination, feed, carcass weight, and the discount rate, with representative values for the year 2024. Herd-level inputs (average herd milk production per year per cow, birth weight, adult dairy cow weight, length of voluntary waiting period, estrus detection rate, conception rate, and age at first calving) were extracted from an on-farm herd management software program. The result illustrated that economic benefits and RPO values for pregnant and open cows vary by lactation stage and number. Pregnant cows have higher RPO values than open cows in both systems. On organic farms, pregnant cows' RPO values range from -$110 to $3,373, whereas open cows' values range from -$109 to $1,681 based on the production level and lactation. The RPO for all of the lactation, pregnancy, and production level combinations were higher for organic systems. The average difference in RPO between 2 systems ranged from $1,000 to $200 for lactations 1 and 12, respectively, with organic farms exhibiting higher RPO in 805 out of 900 scenarios, favoring longer productive life in organic dairy farms. In conclusion, optimizing productive lifespan of dairy cows through dynamic culling decisions can lead to increased profitability for organic herds, which, in our analysis, was higher than that of conventional herds.