title: Nitrogen excretion and ammonia emissions from pigs fed modified diets.
abstract: Two swine feeding trials were conducted (initial body weight = 47 +/- 2 and 41 +/- 3 kg for Trials 1 and 2, respectively) to evaluate reduced crude protein (CP) and yucca (Yucca schidigera Roezl ex Ortgies) extract-supplemented diets on NH3 emissions. In Trial 1, nine pigs were offered a corn-soybean meal diet (C, 174 g kg(-1) CP), a Lys-supplemented diet (L, 170 g kg(-1) CP), or a 145 g kg(-1) CP diet supplemented with Lys, Met, Thr, and Trp (LMTT). In Trial 2, nine pigs were fed diet L supplemented with 0, 62.5, or 125 mg of yucca extract per kg diet. Each feeding period consisted of a 4-d dietary adjustment followed by 72 h of continuous NH3 measurement. Urine and fecal samples were collected each period. Feeding the LMTT diet reduced (P < 0.05) average daily gain (ADG) and feed efficiency (G:F) compared to diet L. Fecal N concentration decreased with a reduction in dietary CP, but urinary ammonium increased from pigs fed diet LMTT (2.0 g kg(-1), wet basis) compared to those fed diet C (1.1 g kg(-1)) or L (1.0 g kg(-1)). When pigs were fed reduced CP diets NH3 emission rates decreased (2.46, 2.16, and 1.05 mg min(-1) for diets C, L, and LMTT). Yucca had no effect on feed intake, ADG, or G:F. Ammonium and N concentrations of manure and NH3 emission rates did not differ with yucca content. Caution must be executed to maintain animal performance when strategies are implemented to reduce NH3 emissions.
authors.affiliation: Department of Animal Science, Iowa State University, Ames, IA 50011, USA.
authors.forename: D M
authors.initials: DM
authors.lastname: Panetta
authors.forename: W J
authors.initials: WJ
authors.lastname: Powers
authors.forename: H
authors.initials: H
authors.lastname: Xin
authors.forename: B J
authors.initials: BJ
authors.lastname: Kerr
authors.forename: K J
authors.initials: KJ
authors.lastname: Stalder
mesh_terms: D000641:Ammonia / Q000032:analysis* / Q000378:metabolism; D000821:Animal Feed; D000818:Animals; D005243:Feces / Q000737:chemistry*; D009584:Nitrogen / Q000032:analysis* / Q000378:metabolism; D013552:Swine / Q000378:metabolism*; D013997:Time Factors; D014556:Urine / Q000737:chemistry*
chemical_list: D000641:Ammonia; D009584:Nitrogen