Impact of vitamin and mineral supplement withdrawal and wheat middling inclusion on finishing pig growth performance, fecal mineral concentration, carcass characteristics, and the nutrient content and oxidative stability of pork1

Abstract

A study was conducted to determine if supplement withdrawal (omission of dietary vitamin and trace mineral premixes and a two-thirds reduction in dietary inorganic phosphorus) for 28 d preslaughter and the feeding of wheat middlings (dietary concentrations of 5, 15, and 30% from weaning to 16, 16 to 28, and 28 kg to slaughter, respectively) affect growth performance, carcass characteristics, and fecal mineral concentrations ofthe pig, as well as the nutrient content and oxidative stability of the longissimus dorsi muscle. Crossbred pigs (n = 64) were blocked by weight and assigned to one of four dietary treatments in a 2 x 2 factorial design (with or without supplement withdrawal, and with or without wheat middlings). Supplement withdrawal and wheat middling inclusion did not influence average daily gain (ADG), average daily feed intake, gain/feed, or carcass traits, except for a decrease (P < 0.01) in the ADG of pigs from 28 to 65 kg when fed wheat middlings. Supplement withdrawal decreased (P < 0.01) fecal Ca, P, Cu, Fe, Mn, and Zn concentrations. In diets containing full vitamin and mineral supplementation, wheat middling inclusion decreased (P < 0.01) fecal Ca, Cu, Fe, and Zn concentrations and increased (P < 0.01) fecal Mn. Supplement withdrawal decreased (P < 0.05) concentrations of riboflavin, niacin, and P in the longissimus dorsi muscle, but did not affect longissimus dorsi thiamin, vitamin E, Fe, Cu, Zn, and Ca concentrations. Inclusion of wheat middlings increased (P < 0.04) longissimus dorsi thiamin, niacin, riboflavin, and vitamin E concentrations and decreased (P < 0.04) Cu concentrations. However, wheat middling inclusion did not affect (P > 0.05) longissimus dorsi Ca, P, Fe, and Zn concentrations. Dietary treatment did not affect either Cu/Zn superoxide dismutase or glutathione peroxidase activity in the longissimus dorsi. The results from this study indicate that supplement withdrawal and dietary wheat middling inclusion alter pork nutrient content and fecal mineral concentration, but not the oxidative stability of pork.

Effect of added zinc in diets with ractopamine hydrochloride on growth performance, carcass characteristics, and ileal mucosal inflammation mRNA expression of finishing pigs1,2

“…Plasma was deproteinized by diluting 1:4 in 12.5% trichloroacetic acid followed by centrifugation at 2,000 × g for 15 min at 4°C (GS-6KR; Beckman-Coulter, Brea, CA), with the resulting supernatant collected for analysis. Zinc analysis was determined by flame atomic absorption spectrophotometry according to the methods of Shaw et al (2002;UNICAM 989 Solar AA Spectrometer;Thermo Elemental Corp., Franklin, MA).…”

“…Liver, loin, and feed samples were microwave digested (MARS 5; CEM Corp., Matthews, NC) in 10 mL of HNO 3 followed by addition of 2 mL of H 2 O 2 (Shaw et al, 2002). Samples were brought to constant volume and diluted appropriately for Zn analysis described previously.…”

Effect of replacing dietary FeSO₄ with equal Fe-levelled iron glycine chelate on broiler chickens

“…Liver samples were prepared for analysis according to the method of Ji et al (2009). Liver Cu/Zn superoxide dismutase (SOD) activity was determined by the method of Shaw et al (2002). Protein was measured by the method of Lowry et al (1951).…”

Effect of adding macro and micro minerals in pig feces fed diets with different levels of probiotic

“…The lowest Zn excretion by animals treated with 200 and 300 ppm might be related to the action of microorganisms present in probiotic, which used Zn in their physiological functions (Mc Dowell, 1992). When levels of macro and micro minerals in feces of growing pigs fed diet without probiotic determined in this trial (Ca = 2.01%, P = 2.6%, Zn = 1095 ppm, Cu = 104 ppm and Fe = 1845 ppm) were compared to results found by Lima et al (1993) using the same fecal collection method in animals at finishing phase (Ca = 3.39 %, P = 2.67 %, Zn = 830 ppm, Cu = 124 ppm and Fe = 6010 ppm and to values observed by Shaw et al (2002) for the control diet of their study envolving finishing pigs (Ca = 2.68%, P = 1.94%, Zn = 801 ppm, Cu = 98 ppm and Fe = 1829 ppm), it was observed that all minerals, with exception of the Zn, were in lower concentrations in the present and in the Shaw et al (2002) studies than in Lima et al (1993) study. The genetic potential of animals must be considered in order to explain the differences (Crocker and Robison, 2002), but the composition of the diets and the level of trace mineral inclusion influences the mineral composition of feces too, as showed by Shaw et al (2002).…”