Boron supplementation of a semipurified diet for weanling pigs improves feed efficiency and bone strength characteristics and alters plasma lipid metabolites

Two experiments were conducted to determine effects of dietary boron (B) on performance, plasma minerals and metabolites, and bone characteristics in young pigs. In Experiment 1, 48 pigs (24 males, 24 females; 21 d old) were allotted to pens, which were randomly assigned to one of the following diet ary treatments: I) control (natural ingredient diet; 6.7 mg B/kg diet), 2) control + 5 mg B/kg diet and 3) control + 15 mg B/kg diet. Boron was supple mented as sodium berate, In Experiment 2, 48 pigs (24 males, 24 females; 21 d old) were assigned to the same treatments described in Experiment 1; how ever, the basal diet was a semipurified diet (0.98 mg B/kg diet). Diets wer e fed for 40 d; on d 40, blood samples were obtained for determination of p lasma mineral and metabolite concentrations. Femurs were harvested from 8 p igs per treatment on d 40 for determination of mechanical properties, ash a nd lipid percentage. In Experiment 1, B did not affect performance, plasma minerals or metabolites or bone properties. In Experiment 2, B supplementat ion improved (P < 0.05) the gain:feed ratio and increased plasma cholestero l and triglyceride concentrations. There was a treatment x sex interaction (P < 0.05) in Experiment 2 for bone lipid to be lower and bending moment to be higher, with the response occurring in male pigs. Other dependent varia bles in Experiment 2 were not affected by treatment. In conclusion, B suppl ementation of a low B diet elicited responses of physiologic importance to pigs, However, B supplementation of a natural ingredient diet did not elici t a response.