4ZORIC M, NILSSON E, MATTSSON S, et al. Abrasions and lameness in piglets born in different farrowing systems with different types of floor[J]. Acta Vet Scand,2008,50:37.
5KOSIEWICZ M M, ZIRNHELD A L, ALARD P. Gut microbi- ota,immunity, and disease: a complex relationship[J]. Front Microbiol, 2011,180(2) : 1-11.
8Rosebrough RW,Steel NC,Mcmurtry JP.Effect of protein level and supplemental lysine on growth and urea cycle enzyme activity in the pig[J].Growth, 1983,47(4):348-360.
9Borg BS,Libal GM,Wahlkstrom RC.Tryptophan and threonine requirements of young pigs and their efects on serun calcium,phosphorus and zinc concentrations [J]. Journal of Animal Science, 1987,64(8): 1070-1078.
10Fagarasan S,Honjo T.Regulation of IgA synthesis at mucosal surfaces [J].Current Opinion in Immunology,2004,16(3): 277-283.