Popis: |
Dried blood cells (DBC) contain low levels of Ile relative to Lys, and thus Ile may become limiting in pig diets supplemented with DBC. Therefore, 3 experiments were conducted to evaluate the effect of increasing DBC in corn-soybean meal–based diets in weanling (7 to 13 kg, Exp. 1 and 2) and grower (24 to 46 kg, Exp. 3) pigs. Treatments were replicated with 4 to 6 pens of 4 to 6 pigs per pen. In Exp. 1 and 2 (14 d), all diets contained 0.10% l-Lys·HCl and DBC were added at 2% increments from 0 to 8%. In Exp. 1, all diets contained 1.40% total dietary Lys. All diets in Exp. 2 contained 1.185% apparent ileal digestible Lys. In Exp. 1, increasing dietary DBC resulted in a linear decrease in ADFI (P 0.10). In Exp. 2, increasing dietary DBC resulted in a decrease in ADG (linear and quadratic, P < 0.01) and a linear decrease in ADFI and G:F (P < 0.05). Experiment 3 was conducted for 28 d to determine the effect of graded levels of DBC. In Exp. 3, DBC were added to the diets at 2% increments from 0 to 8%. All diets contained 1.00% total dietary Lys. In Exp. 3, increasing dietary DBC resulted in a decrease in ADG and ADFI (linear, P < 0.01). Feed efficiency was not significantly affected by the increasing levels of DBC. The results of these 3 experiments indicate that ADG can be maintained with up to 4% DBC, but DBC fed above 2% may have a negative effect on feed efficiency of weanling and grower pigs. The maximum inclusion level of DBC that can be added in a diet for weanling and growing pigs without reducing growth performance is dependent on the Ile:Lys. |