title: Effects of lactose and yeast-dried milk on growth performance, fecal microbiota, and immune parameters of nursery pigs.
abstract: An experiment was conducted to evaluate the effects of dietary lactose alone or in combination with a yeast-dried milk product (50% dried near-dated milk and 50% dried yeast) on growth performance, fecal microbiota, and immune status in nursery pigs (Sus scrofa). A total of 108 pigs (age, 20 ± 1 d; initial BW, 6.07 ± 0.03 kg) were randomly allotted to 18 pens (6 pigs/pen; 6 pens/treatment). Dietary treatments were: 1) control, 2) control + lactose, and 3) control + lactose + 5% yeast-dried milk. Except for the control diet, diets in Phase 1 (wk 1 and 2), 2 (wk 3 and 4), and 3 (wk 5) contained 20, 15, and 5% total lactose, respectively. Blood samples were collected from all pigs at d 0, 14, 28, and 35 to determine circulating IgG, IgA, and tumor necrosis factor (TNF)-α concentrations. At d 0, 7, and 14, fecal samples were collected (n = 18; 6 pigs/treatment) to evaluate fecal microbiota using PCR-denaturing gradient gel electrophoresis. Compared with pigs fed the control diet, pigs fed lactose and lactose with yeast-dried milk had greater (P < 0.05) ADG and tended (P = 0.07) to have greater BW and ADFI during Phase 1. There were no differences for BW, ADG, or ADFI during Phase 2, 3, or the overall experimental period. A main effect of treatment was observed for circulating IgA where control pigs had greater (P < 0.01) IgA compared with pigs fed lactose with or without yeast-dried milk; however, no effects of treatment were observed (P > 0.10) for circulating IgG or TNF-α. No differences (P > 0.10) in microbial diversity indices were observed on d 7 or 14 among treatments. However, a shift in microbial composition was observed on d 7, with lactose-fed pigs having greater (P < 0.05) putative L. johnsonii staining intensity compared with control pigs and pigs fed lactose plus yeast-dried milk. On d 14, L. delbrueckii was eliminated (P < 0.04) by feeding lactose with or without yeast-dried milk. This research indicates that growth performance, immune status, and fecal microbiota are affected by dietary inclusion of lactose alone, or in combination with yeast-dried milk.
authors.affiliation: Department of Animal Science, University of Nebraska, Lincoln 68583, USA.
authors.forename: H
authors.initials: H
authors.lastname: Tran
authors.forename: R
authors.initials: R
authors.lastname: Moreno
authors.forename: E E
authors.initials: EE
authors.lastname: Hinkle
authors.forename: J W
authors.initials: JW
authors.lastname: Bundy
authors.forename: J
authors.initials: J
authors.lastname: Walter
authors.forename: T E
authors.initials: TE
authors.lastname: Burkey
authors.forename: P S
authors.initials: PS
authors.lastname: Miller
mesh_terms: D000821:Animal Feed / Q000032:analysis*; D000818:Animals; D058645:Denaturing Gradient Gel Electrophoresis; D004032:Diet / Q000662:veterinary; D005243:Feces / Q000382:microbiology; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects / Q000276:immunology; D007070:Immunoglobulin A / Q000097:blood; D007074:Immunoglobulin G / Q000097:blood; D007785:Lactose / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology*; D008297:Male; D008892:Milk / Q000737:chemistry* / Q000378:metabolism; D013552:Swine / Q000097:blood / Q000254:growth & development* / Q000276:immunology / Q000382:microbiology; D014409:Tumor Necrosis Factor-alpha / Q000097:blood; D015003:Yeasts
chemical_list: D007070:Immunoglobulin A; D007074:Immunoglobulin G; D014409:Tumor Necrosis Factor-alpha; D007785:Lactose