Interpretive Summary: The effect of life history events on carcass merit and price of cull dairy cows
By Anne Zinn
Each year, 27-37% of dairy cows are removed from dairy herds due to reproductive failure, low milk production, and/or udder disease. Once a dairy cow is no longer able to produce milk, it becomes a beef cow, which contributes ~10% of national beef production in the United States. The first of its kind, a study was published in the Journal of Animal Science reporting on life history events affecting sale barn price and carcass merit of cull dairy cows. The objectives were to assess relationships between price ratio and carcass merit of cull dairy cows sold through several sites of an auction market and to investigate the effect of animal life history events and live weight on sale barn price and price ratio, as an indicator of carcass merit.
Results indicated that price ratio was highly correlated with carcass traits, which became a good indicator of overall carcass merit. The life history events that had the most impact on sale barn price and price ratio were lactation number, days open, days dry, total milk production, and total milk solids production. These life history events and their association with cow body condition and health were decisive factors when determining cow price, which meant cow price was often highly associated with carcass merit of cull dairy cows.
Overall, the results indicated that life history events affect carcass merit of cull dairy cows and contribute to their final price. Additional research is recommended to further investigate the differences in stage of lactation and to identify other factors involved, such as health events. In the future, knowledge of farm-level effects, life events, carcass, and meat quality variables could improve management decisions, maximize cow value, and improve the final meat quality of dairy cows.
The full paper can be found on the Journal of Animal Science webpage.