Jeffrey D. Ward

Learn More
A study was conducted to determine the effects of supplementing a diet marginally deficient in copper (Cu) with iron (Fe), molybdenum (Mo), or Cu on phagocytic cell function and disease resistance of calves. Thirty-one calves were born to heifers fed a corn silage-based diet containing 4.5 mg of Cu/kg. Treatments consisted of 1) control (CON; no(More)
Two experiments were conducted to determine the effects of Cu deficiency with or without high dietary Mo or Fe on the specific immunity of calves. In Exp. 1, calves from 38 bred heifers, fed corn silage-based experimental diets from the last third of gestation until the calves were weaned, were used. Dietary treatments were control (no supplemental Fe, Mo,(More)
This study was conducted to determine the effect of zinc level and source on growth performance, tissue Zn concentrations, intracellular distribution of Zn, and immune response in weanling pigs. Ninety-six 3-wk-old crossbred weanling pigs (BW = 6.45 +/- 0.17 kg) were assigned to one of six dietary treatments (four pigs per pen, four replicates per(More)
Two in vitro experiments were conducted to estimate the availability of Cu from Cu Lys compared with Cu from CuSO4. In experiment 1, a 24-h ruminal fermentation (alpha-cellulose substrate) containing either .1% added S or 2% added urea was performed with 4, 12, or 96 ppm of added Cu as either Cu Lys or CuSO4. Soluble Cu was measured at the end of the 24-h(More)
An experiment was conducted over a 2-yr period to investigate the influence of grain crude protein (CP) and rumen undegradable protein (RUP) concentration on reproduction and energy status of dairy cows grazing annual ryegrass (Lolium multiflorum) and oats (Avena sativa). Holstein cows (n = 122) were blocked by calving group [partum (0 d postpartum) vs.(More)
A study was conducted to determine the effects of copper (Cu) depletion by feeding diets high in either iron (Fe) or molybdenum (Mo) on performance and Cu status of beef cows and calves. Thirty-eight 2-yr-old beef heifers, entering the last one-third of gestation, were randomly assigned by expected calving date to one of four diets: 1) control (CON; corn(More)
We used 42 Angus bull calves (7 mo of age) to determine long-term effects of low Cu diets with or without supplemental Mo on performance, carcass characteristics, and Cu status. Twenty-two bulls were injected with 90 mg of Cu 28 d before weaning. After weaning, injected steers were fed a diet supplemented with 7.5 mg of Cu/kg of DM; control steers received(More)
Two experiments were conducted to determine the relative bioavailabilities of Cu proteinate, CuCO3, and CuSO4. In Experiment 1, 30 heifers that had been depleted of Cu were us 1. Treatments were control, Cu proteinate A, Cu proteinate B, CuCO3, and CuSO4. Sources provided 50 mg of Cu/d. Supplementation increased plasma Cu by d 21, but there were no(More)
One hundred twenty-six crossbred steers (218 kg initial BW) were used to determine the availability of Cu from copper lysine (CuLys) relative to CuSO4. Steers were assigned to pens (four replicates per treatment) based on BW and initial plasma Cu concentration and fed a corn silage-based diet supplemented with 0 or 5 ppm of Cu from either CuSO4 or CuLys.(More)
Thirty-eight pregnant Angus, Charolais, and Simmental heifers and their offspring were used to determine whether differences in Cu metabolism existed among breeds. The heifers were fed either 0 or 10 mg of supplemental Cu per kilogram of DM. Calves were born between d 70 and 125 of the 280 d experiment. There were few differences among breeds in plasma Cu(More)