PSXI-41 Investigating the relationship between life history factors, live animal auction price, and carcass quality of cull dairy cows

Abstract High production efficiency is crucial for the competitiveness and sustainability of the dairy industry. To maintain high production, maximize profitability, and allow an accelerated genetic improvement, it is recommended that between 25–30% of dairy herds be renewed each year. Cull dairy cows contribute for approximately 10% of the total beef produced in the United States, being significantly important as a beef source for the meat industry. Furthermore, cull cows provide an important additional income to dairy farmers. However, culling decisions should be carefully made, taking into consideration herd replacement rate, cow performance, milk and beef prices, and the potential price that each cow might be paid for. The objective of this study was to investigate the relationships between life history factors, live animal auction price, and carcass quality of cull dairy cows. Data from three Wisconsin herds were collected using DairyComp software, from January 2018 to January 2019. Hundredweight (cwt) prices paid for each cow (n = 84) were obtained from a marketing auction, and their carcass traits were provided by a commercial meat packing plant. Correlation and multiple linear regression analyses were used to investigate the dependencies between variables. Results indicate that lactation number and days in milk significantly affect cow live weight and that these three variables together with season of the year and farm provide a good predictor of cwt price (adj R2 = 71.7%). Moreover, there were also significant and moderately strong correlations between cwt price and some carcass quality indicators such as dressing (r = 0.57, P < 0.001), trimming losses (r = -0.25, P < 0.05), and grade (r = -0.58, P < 0.001). In conclusion, cull cow cwt price and carcass quality can be improved by taking into account cows life history factors when making culling decisions.