Abstract Two studies were conducted to determine the effects of supplemental chromium (0 or 10 μg... more Abstract Two studies were conducted to determine the effects of supplemental chromium (0 or 10 μg/g as CrCl 3· 6H 2 O) on blood constituents in growing lambs fed a low or high fiber diet. The basal low and high fiber diets were comprised of conventional feeds (corn, ...
plasma characteristics of growing beef steers fed corn silage The effects of lysocellin and varyi... more plasma characteristics of growing beef steers fed corn silage The effects of lysocellin and varying calcium levels on performance and ruminal and 1990, 68:483-489. J ANIM SCI http://jas.fass.org/content/68/2/483 the World Wide Web at:
Glucose tolerance and concentrations of insulin, somatotropin, insulin-like growth factor-1 and c... more Glucose tolerance and concentrations of insulin, somatotropin, insulin-like growth factor-1 and cortisol were evaluated in lambs deficient, marginal or adequate in zinc. There were three treatments: 1) defi cient (basal diet deficient in zinc; 3.7 mg zinc/kg diet); 2) marginal (basal diet + 5 mg zinc/kg diet); and 3) adequate (basal diet + 40 mg zinc/kg diet). Lambs fed the
supplemental molybdenum and sulfur performance, and immune response in growing steers fed diets w... more supplemental molybdenum and sulfur performance, and immune response in growing steers fed diets with or without Effect of copper level and source (copper lysine vs copper sulfate) on copper status, 1993, 71:2748-2755. J ANIM SCI http://jas.fass.org/content/71/10/2748 the World Wide Web at:
Growing steers were used in a replicated 3x3 Latin square to study the influence of ionophores on... more Growing steers were used in a replicated 3x3 Latin square to study the influence of ionophores on mineral metabolism and ruminai urease activity. Treatments consisted of: 1) basal high energy diet; 2) basal plus 33 ppm lasalocid and 3) basal plus 33 ppm monensin. Each period was 33 days and apparent absorption and retention of macrominerals were measured during the last 5 days of each period. Mineral intake during the collection period was not affected by treatment. Both ionophores increased apparent absorption of sodium, magnesium and phosphorus. Retention of magnesium and phosphorus were higher for steers receiving either lasalocid or monensin. Potassium and calcium absorption were not significantly affected by treatment. Serum concentrations of macrominerals were similar for all treatments. Zinc and copper concentrations in serum were higher in animals fed monensin or lasalocid. Steers fed either ionophore had lower concentrations of soluble potassium and calcium in rumen fluid. Both ionophores also decreased ruminai osmolality. Bacterial urease, a nickel-dependent enzyme, was decreased by 28 and 66% in animals that received lasalocid and monensin, respectively. These findings indicate that lasalocid and monensin affect metabolism of certain minerals in ruminants.
Glucose tolerance and concentrations of insulin, somatotropin, insulin-like growth factor-1 and c... more Glucose tolerance and concentrations of insulin, somatotropin, insulin-like growth factor-1 and cortisol were evaluated in lambs deficient, marginal or adequate in zinc. There were three treatments: 1) defi cient (basal diet deficient in zinc; 3.7 mg zinc/kg diet); 2) marginal (basal diet + 5 mg zinc/kg diet); and 3) adequate (basal diet + 40 mg zinc/kg diet). Lambs fed the zinc-deficient diet had lower (P < 0.05) serum insulin concentrations l h after feeding compared with those fed the marginal diet, whereas the concentrations in lambs fed the adequate diet were intermediate. Dietary zinc did not affect plasma glucose or serum somatotropin before or after feeding or intravenous glucose administration. A growth hormone-releasing factor analog was given to evaluate concentrations of somatotropin. Serum somatotropin in response to growth hormone-releasing factor analog tended to be higher (P = 0.20) in deficient and marginal lambs when compared with adequate lambs. Serum insulin-like growth factor-I was lower (P < 0.05) in deficient lambs than in marginal or adequate lambs. Cortisol concentra tions were not affected (P > 0.05) by zinc status. Severe zinc deficiency altered circulating concentrations of in sulin, insulin-like growth factor-I and somatotropin, whereas a marginal deficiency had no effect in growing lambs. J. Nutr. 123: 13-19, 1993.
The present study was conducted to de termine if a selenium deficiency affects the primary and se... more The present study was conducted to de termine if a selenium deficiency affects the primary and secondary humoral immune response of calves challenged with infectious bovine rhinotracheitis virus (IBRV) and to evaluate changes in glutathione peroxidase (GSH-Px) and creatine phosphokinase activities associated with selenium deficiency and viral stress. Treatments included 1) +Se (0.2 mg/kg diet) and 2) -Se (0.03 mg/kg diet). Calves were adapted to their assigned diets during an 84-d de pletion period. By d 42 of the depletion period, whole-blood GSH-Px was lower for -Se calves than for + Se calves. Differences between treatments in plasma GSH-Px were observed by d 14. On d 84, Se-dependent GSH-Px activity in liver was higher in + Se calves. After depletion of -Se calves, animals in both treatments were intranasally inoc ulated with IBRV on d 0 and 35 of the 70-d challenge phase. Whole-blood and plasma GSH-Px increased after IBRV inoculation in +Se calves but not in Se-deficient calves. Serum IgM was higher for + Se calves throughout the challenge phase. Serum IgM increased in both treat ments after primary IBRV inoculation but was unaffected by secondary challenge. Serum IgG was not affected by selenium status but increased in both treatments after sec ondary IBRV challenge. Serum IBRV antibody titers in creased after inoculation on d 0 and 35. By d 49, IBRV antibody titers were higher for +Se calves than in Sedeficient calves. These results indicate that selenium de ficiency may depress the immune response of calves chal lenged with a foreign pathogen. J. Nutr. 118:229-235, 1988.
Journal of the American Veterinary Medical Association
Ninety steers with an average weight of 214 kg were purchased at 2 feeder calf sales and transpor... more Ninety steers with an average weight of 214 kg were purchased at 2 feeder calf sales and transported 70 to 100 km. On arrival at the feedlot, steers were weighed and identified, blood was withdrawn, and the steers were vaccinated against bovine herpesvirus-1 (BHV-1) and parainfluenza3 (PI3), using a modified live vaccine, and randomly assigned to treatment groups. Treatments were: control (no supplemental zinc; zinc methionine; and zinc oxide. The control diet contained 26 mg of zinc/kg diet, and zinc was added in treatments 2 and 3 to provide 25 mg of supplemental zinc/kg diet. Neutralizing antibody titers were determined on serum samples taken on days 0 and 14 as a measure of the immune response to BHV-1 and PI3 vaccination. Weight gains for the 28-day study were similar across treatments. Dry matter intake tended to be higher in steers fed supplemental zinc from either source, because steers fed zinc methionine and zinc oxide consumed 5.2 and 4.4% more feed, respectively, than controls. Antibody titers against BHV-1 tended to be higher in steers supplemented with zinc methionine on day 14. Differences between treatments were not found for PI3 titers. Mortalities did not occur and morbidity rate was low.
This study was conducted to determine the effect of dietary selenium (Se) and vitamin E (Vit E) o... more This study was conducted to determine the effect of dietary selenium (Se) and vitamin E (Vit E) on various blood characteristics and the primary and secondary humoral immune response of lambs challenged with parainfluenza s virus (PIsV). Treatments included: 1) +Se/+Vit E, 2) -Se/ +Vit E~ 3) +Se/-Vit E and 4) -Se/-Vit E. The basal diet (-Se/-Vit E) was deficient in Se and Vit E. Sodium selenite (.2 mg Se/kg diet) and alpha-tocopherol acetate (20 mg Vit E/kg diet) were added to +Se and +Vit E diets, respectively, to provide adequate levels of each according to NRC recommendations. Following a lO-wk dietary adaptation and depletion period, lambs in all treatmeat groups were intratracheally inoculated with PIsV on d 0 and 35 of the 70-d study. Prior to inoculation, whole blood and plasma gintathione peroxidase (GSH-Px) activities were higher (P < .01) for +Se lambs. Whole blood and plasma GSH-Px increased (P < .01) after primary viral inoculation in +Se lambs but not in -Se lambs. Serum irnmunoglobulin M (IgM) concentrations were enhanced (P < .05) by Se supplementation on d 14, 35 and49 of the study. Selenium and(or) Vit E did not affect serum immunoglobulin G (IgG) levels. Serum PIsV antibody titers increased after inoculation on d 0 and 35 in all treatment groups. Titer levels appeared to increase more substantially for +Se lambs after primary inoculation, but increases were greater (P < .01) for +Vit E lambs after secondary challenge. Our results indicate that Se and Vit E independently enhance the immune response of lambs challenged with a viral pathogen. (
Two experiments were conducted to determine the effects of dietary B on the production of cytokin... more Two experiments were conducted to determine the effects of dietary B on the production of cytokines following an endotoxin challenge. In both experiments, pigs were obtained from litters generated from sows fed low-B (control) or B-supplemented (5 mg/ kg, as-fed basis) diets. In Exp. 1 and 2, 28 and 35 pigs, respectively (21 d old), remained with their littermates throughout a 49-d nursery phase and were fed either a control or B-supplemented diet. In Exp. 1, 12 pigs per treatment were moved to individual pens at the completion of the nursery phase and fed their respective experimental diet. On d 99 of the study, pigs were injected with 150 g of phytohemagglutinin (PHA) to evaluate a local inflammatory response. Pigs receiving the B-supplemented diet had a decreased (P < 0.01) inflammatory response following PHA injection. Peripheral blood monocytes were isolated from six pigs per treatment on d 103 and cultured in the presence of lipopolysaccharide (LPS) to determine the effect of dietary B on tumor necrosis factor-α (TNF-α) production from monocytes. Isolated monocytes from pigs that
We conducted an experiment to determine the effects of dietary copper (Cu) source and level on ca... more We conducted an experiment to determine the effects of dietary copper (Cu) source and level on carcass characteristics, longissimus muscle fatty acid composition, and serum and muscle cholesterol concentrations in steers. Sixty Angus and Angus × Hereford steers were stratified by weight and initial liver Cu concentration within a breed and randomly assigned to treatments. Treatments consisted of: 1) control (no supplemental Cu); 2) 20 mg Cu/kg DM from Cu sulfate (CuSO 4 ); 3) 40 mg Cu/kg DM from CuSO 4 ; 4) 20 mg Cu/kg DM from Cu citrate; 5) 20 mg Cu/kg DM from Cu proteinate; and 6) 20 mg Cu/kg DM from tribasic Cu chloride. A corn silage-soybean meal-based diet was fed for 56 d. Steers were then switched to a high-concentrate diet. Equal numbers (n = 5) of steers per treatment were slaughtered after receiving the finishing diets for
Neonatal pigs (143) were used to determine if adequate iron (Fe) would be stored following a sing... more Neonatal pigs (143) were used to determine if adequate iron (Fe) would be stored following a single oral dose of Fe methionine (FeMet) to prevent anemia through 21 d of age.
Abstract Two studies were conducted to determine the effects of supplemental chromium (0 or 10 μg... more Abstract Two studies were conducted to determine the effects of supplemental chromium (0 or 10 μg/g as CrCl 3· 6H 2 O) on blood constituents in growing lambs fed a low or high fiber diet. The basal low and high fiber diets were comprised of conventional feeds (corn, ...
plasma characteristics of growing beef steers fed corn silage The effects of lysocellin and varyi... more plasma characteristics of growing beef steers fed corn silage The effects of lysocellin and varying calcium levels on performance and ruminal and 1990, 68:483-489. J ANIM SCI http://jas.fass.org/content/68/2/483 the World Wide Web at:
Glucose tolerance and concentrations of insulin, somatotropin, insulin-like growth factor-1 and c... more Glucose tolerance and concentrations of insulin, somatotropin, insulin-like growth factor-1 and cortisol were evaluated in lambs deficient, marginal or adequate in zinc. There were three treatments: 1) defi cient (basal diet deficient in zinc; 3.7 mg zinc/kg diet); 2) marginal (basal diet + 5 mg zinc/kg diet); and 3) adequate (basal diet + 40 mg zinc/kg diet). Lambs fed the
supplemental molybdenum and sulfur performance, and immune response in growing steers fed diets w... more supplemental molybdenum and sulfur performance, and immune response in growing steers fed diets with or without Effect of copper level and source (copper lysine vs copper sulfate) on copper status, 1993, 71:2748-2755. J ANIM SCI http://jas.fass.org/content/71/10/2748 the World Wide Web at:
Growing steers were used in a replicated 3x3 Latin square to study the influence of ionophores on... more Growing steers were used in a replicated 3x3 Latin square to study the influence of ionophores on mineral metabolism and ruminai urease activity. Treatments consisted of: 1) basal high energy diet; 2) basal plus 33 ppm lasalocid and 3) basal plus 33 ppm monensin. Each period was 33 days and apparent absorption and retention of macrominerals were measured during the last 5 days of each period. Mineral intake during the collection period was not affected by treatment. Both ionophores increased apparent absorption of sodium, magnesium and phosphorus. Retention of magnesium and phosphorus were higher for steers receiving either lasalocid or monensin. Potassium and calcium absorption were not significantly affected by treatment. Serum concentrations of macrominerals were similar for all treatments. Zinc and copper concentrations in serum were higher in animals fed monensin or lasalocid. Steers fed either ionophore had lower concentrations of soluble potassium and calcium in rumen fluid. Both ionophores also decreased ruminai osmolality. Bacterial urease, a nickel-dependent enzyme, was decreased by 28 and 66% in animals that received lasalocid and monensin, respectively. These findings indicate that lasalocid and monensin affect metabolism of certain minerals in ruminants.
Glucose tolerance and concentrations of insulin, somatotropin, insulin-like growth factor-1 and c... more Glucose tolerance and concentrations of insulin, somatotropin, insulin-like growth factor-1 and cortisol were evaluated in lambs deficient, marginal or adequate in zinc. There were three treatments: 1) defi cient (basal diet deficient in zinc; 3.7 mg zinc/kg diet); 2) marginal (basal diet + 5 mg zinc/kg diet); and 3) adequate (basal diet + 40 mg zinc/kg diet). Lambs fed the zinc-deficient diet had lower (P < 0.05) serum insulin concentrations l h after feeding compared with those fed the marginal diet, whereas the concentrations in lambs fed the adequate diet were intermediate. Dietary zinc did not affect plasma glucose or serum somatotropin before or after feeding or intravenous glucose administration. A growth hormone-releasing factor analog was given to evaluate concentrations of somatotropin. Serum somatotropin in response to growth hormone-releasing factor analog tended to be higher (P = 0.20) in deficient and marginal lambs when compared with adequate lambs. Serum insulin-like growth factor-I was lower (P < 0.05) in deficient lambs than in marginal or adequate lambs. Cortisol concentra tions were not affected (P > 0.05) by zinc status. Severe zinc deficiency altered circulating concentrations of in sulin, insulin-like growth factor-I and somatotropin, whereas a marginal deficiency had no effect in growing lambs. J. Nutr. 123: 13-19, 1993.
The present study was conducted to de termine if a selenium deficiency affects the primary and se... more The present study was conducted to de termine if a selenium deficiency affects the primary and secondary humoral immune response of calves challenged with infectious bovine rhinotracheitis virus (IBRV) and to evaluate changes in glutathione peroxidase (GSH-Px) and creatine phosphokinase activities associated with selenium deficiency and viral stress. Treatments included 1) +Se (0.2 mg/kg diet) and 2) -Se (0.03 mg/kg diet). Calves were adapted to their assigned diets during an 84-d de pletion period. By d 42 of the depletion period, whole-blood GSH-Px was lower for -Se calves than for + Se calves. Differences between treatments in plasma GSH-Px were observed by d 14. On d 84, Se-dependent GSH-Px activity in liver was higher in + Se calves. After depletion of -Se calves, animals in both treatments were intranasally inoc ulated with IBRV on d 0 and 35 of the 70-d challenge phase. Whole-blood and plasma GSH-Px increased after IBRV inoculation in +Se calves but not in Se-deficient calves. Serum IgM was higher for + Se calves throughout the challenge phase. Serum IgM increased in both treat ments after primary IBRV inoculation but was unaffected by secondary challenge. Serum IgG was not affected by selenium status but increased in both treatments after sec ondary IBRV challenge. Serum IBRV antibody titers in creased after inoculation on d 0 and 35. By d 49, IBRV antibody titers were higher for +Se calves than in Sedeficient calves. These results indicate that selenium de ficiency may depress the immune response of calves chal lenged with a foreign pathogen. J. Nutr. 118:229-235, 1988.
Journal of the American Veterinary Medical Association
Ninety steers with an average weight of 214 kg were purchased at 2 feeder calf sales and transpor... more Ninety steers with an average weight of 214 kg were purchased at 2 feeder calf sales and transported 70 to 100 km. On arrival at the feedlot, steers were weighed and identified, blood was withdrawn, and the steers were vaccinated against bovine herpesvirus-1 (BHV-1) and parainfluenza3 (PI3), using a modified live vaccine, and randomly assigned to treatment groups. Treatments were: control (no supplemental zinc; zinc methionine; and zinc oxide. The control diet contained 26 mg of zinc/kg diet, and zinc was added in treatments 2 and 3 to provide 25 mg of supplemental zinc/kg diet. Neutralizing antibody titers were determined on serum samples taken on days 0 and 14 as a measure of the immune response to BHV-1 and PI3 vaccination. Weight gains for the 28-day study were similar across treatments. Dry matter intake tended to be higher in steers fed supplemental zinc from either source, because steers fed zinc methionine and zinc oxide consumed 5.2 and 4.4% more feed, respectively, than controls. Antibody titers against BHV-1 tended to be higher in steers supplemented with zinc methionine on day 14. Differences between treatments were not found for PI3 titers. Mortalities did not occur and morbidity rate was low.
This study was conducted to determine the effect of dietary selenium (Se) and vitamin E (Vit E) o... more This study was conducted to determine the effect of dietary selenium (Se) and vitamin E (Vit E) on various blood characteristics and the primary and secondary humoral immune response of lambs challenged with parainfluenza s virus (PIsV). Treatments included: 1) +Se/+Vit E, 2) -Se/ +Vit E~ 3) +Se/-Vit E and 4) -Se/-Vit E. The basal diet (-Se/-Vit E) was deficient in Se and Vit E. Sodium selenite (.2 mg Se/kg diet) and alpha-tocopherol acetate (20 mg Vit E/kg diet) were added to +Se and +Vit E diets, respectively, to provide adequate levels of each according to NRC recommendations. Following a lO-wk dietary adaptation and depletion period, lambs in all treatmeat groups were intratracheally inoculated with PIsV on d 0 and 35 of the 70-d study. Prior to inoculation, whole blood and plasma gintathione peroxidase (GSH-Px) activities were higher (P < .01) for +Se lambs. Whole blood and plasma GSH-Px increased (P < .01) after primary viral inoculation in +Se lambs but not in -Se lambs. Serum irnmunoglobulin M (IgM) concentrations were enhanced (P < .05) by Se supplementation on d 14, 35 and49 of the study. Selenium and(or) Vit E did not affect serum immunoglobulin G (IgG) levels. Serum PIsV antibody titers increased after inoculation on d 0 and 35 in all treatment groups. Titer levels appeared to increase more substantially for +Se lambs after primary inoculation, but increases were greater (P < .01) for +Vit E lambs after secondary challenge. Our results indicate that Se and Vit E independently enhance the immune response of lambs challenged with a viral pathogen. (
Two experiments were conducted to determine the effects of dietary B on the production of cytokin... more Two experiments were conducted to determine the effects of dietary B on the production of cytokines following an endotoxin challenge. In both experiments, pigs were obtained from litters generated from sows fed low-B (control) or B-supplemented (5 mg/ kg, as-fed basis) diets. In Exp. 1 and 2, 28 and 35 pigs, respectively (21 d old), remained with their littermates throughout a 49-d nursery phase and were fed either a control or B-supplemented diet. In Exp. 1, 12 pigs per treatment were moved to individual pens at the completion of the nursery phase and fed their respective experimental diet. On d 99 of the study, pigs were injected with 150 g of phytohemagglutinin (PHA) to evaluate a local inflammatory response. Pigs receiving the B-supplemented diet had a decreased (P < 0.01) inflammatory response following PHA injection. Peripheral blood monocytes were isolated from six pigs per treatment on d 103 and cultured in the presence of lipopolysaccharide (LPS) to determine the effect of dietary B on tumor necrosis factor-α (TNF-α) production from monocytes. Isolated monocytes from pigs that
We conducted an experiment to determine the effects of dietary copper (Cu) source and level on ca... more We conducted an experiment to determine the effects of dietary copper (Cu) source and level on carcass characteristics, longissimus muscle fatty acid composition, and serum and muscle cholesterol concentrations in steers. Sixty Angus and Angus × Hereford steers were stratified by weight and initial liver Cu concentration within a breed and randomly assigned to treatments. Treatments consisted of: 1) control (no supplemental Cu); 2) 20 mg Cu/kg DM from Cu sulfate (CuSO 4 ); 3) 40 mg Cu/kg DM from CuSO 4 ; 4) 20 mg Cu/kg DM from Cu citrate; 5) 20 mg Cu/kg DM from Cu proteinate; and 6) 20 mg Cu/kg DM from tribasic Cu chloride. A corn silage-soybean meal-based diet was fed for 56 d. Steers were then switched to a high-concentrate diet. Equal numbers (n = 5) of steers per treatment were slaughtered after receiving the finishing diets for
Neonatal pigs (143) were used to determine if adequate iron (Fe) would be stored following a sing... more Neonatal pigs (143) were used to determine if adequate iron (Fe) would be stored following a single oral dose of Fe methionine (FeMet) to prevent anemia through 21 d of age.
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