Effects of a two-meal daily feeding pattern with varied crude protein levels on growth performance and antioxidant indexes in pigs

The present study aimed to evaluate the effects of daily feeding pattern on growth performance, blood biochemistry, and antioxidant indexes in pigs. One hundred and eighty female Duroc × Landrace × Yorkshire (DLY) pigs with similar body weight (11.00 ± 0.12 kg) were randomly assigned to 3 groups: the control group (fed 17.01% CP diet, twice daily); high-low group (H-L group, fed 18.33% CP diet in the morning, followed by 15.70% CP diet in the afternoon); and low-high group (L-H group, fed 15.70% CP diet in the morning, followed by 18.33% CP diet in the afternoon) (n = 6). Comparable amounts of their respective diets were given at 05:30 and 15:00 throughout the experimental periods to make all the treatments consumed the same type of food and the same amount of calories on a daily basis. On day 30, one pig was randomly selected per litter for blood samples. Compared with the control group, ADG in the H-L and L-H groups increased by 8.11% and 16.23%, but not significant (P > 0.05); and blood urea nitrogen (BUN) in the H-L and L-H groups decreased by 26.76% and 41.04% (P < 0.05), respectively. The H-L group feeding pattern could significantly improve levels of serum superoxide dismutase (SOD), when compared with the control group. These findings suggest that the two-meal daily feeding pattern with varied levels of CP affects serum levels of BUN and SOD. These changes could effectively silightly improve growth performance and antioxidant capacity in pigs without incurring increased feeding costs.