Calf performance when fed with cheese whey associated with discarded powdered milk

The objective of this study was to evaluate the performance of calves (Holstein × No Defined Breed Standard) fed powdered cheese whey associated with discarded powdered milk up to 60 days of age. Forty calves (35 kg initial average weight) were used, distributed in a completely randomized design with four treatments and ten repetitions per treatment: whole milk (control), 100% milk powder, 80% milk powder + 20% cheese whey powder, 60% milk powder + 40% cheese whey powder. Consumption, performance, and economic analysis were evaluated. Data were analyzed for variance and comparison of orthogonal contrasts (P < 0.05). No significant differences were observed between the treatments tested regarding the evaluated variables. The animals from all treatments had a final average weight of 50.28 kg as the result of an average weight gain of 0.255 ± 0.03 kg/day and a total dry matter intake of 34.28 ± 1.47 kg/day per calf. The examined diets offered the lowest cost compared to the control treatment, generating an average additional profit of 113.19 R$/animal. Diets containing whey cheese powder are the most economically advantageous options, as replacing 100% of milk with these by-products did not impair animal performance. The use of discarded industrial milk powder combined with whey powder in a ratio of up to 80:20 is a viable option for feeding male calves in dairy farms.