Date of this Version
Increasing concentrations of vitamin B12 were fed to 144 weanling pigs (weaned 13-14 days) in two, five-week trials. Pigs were fed one of six diets: NC, negative control, basal diet without supplemented vitamin B12; or the basal diet with the inclusion of 100% (1X, 7.94 μg/lb), 200% (2X, 15.87 μg/lb), 400% (4X, 31.75 μg/lb), 800% (8X, 63.49 μg/lb), or 1,600% (16X, 126.98 μg/lb) of NRC requirements for the 11- to 22-lb pig. Each trial was divided into two phases: phase 1, day 0 - day 14 and phase 2, day 14 - day 35. Throughout phase 1, there were no differences among treatments, although ADG (average daily gain) and ADFI (average daily feed intake) increased linearly (P< 0.1). During phase 2, the inclusion of B12 resulted in a linear increase (P< 0.05) in ADG with pigs receiving the 16X treatment (126.98 μg/lb) having the greatest gains (ADG = 1.24 lb) in contrast with pigs receiving the control diet (ADG = 1.08 lb). Average daily feed intake increased linearly (P< 0.05) with pigs receiving the control diet consuming less (P< 0.1) than the 2X, 4X, 8X, and 16X treatments during phase 2. Overall (phase 1 and phase 2), ADG increased (P< 0.01) as much as 0.13 lb (16X treatment, 126.98 μg/lb) over the negative control with the inclusion of vitamin B12. Increased concentrations of B12 resulted in a linear increase (P< 0.05) in ADG and ADFI overall. This study suggests that feeding levels of vitamin B12 above the NRC recommendation may improve weight gain and feed intakes of weanling pigs.