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P O Kechele - One of the best experts on this subject based on the ideXlab platform.
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comparative toxicity of selenium from seleno dl methionine sodium selenate and astragalus bisulcatus in pigs
Toxicological Sciences, 1996Co-Authors: K E Panter, L F James, H F Mayland, W J Hartley, Bryan L Stegelmeier, P O KecheleAbstract:PANTER, K. E., HARTLEY, W. J., JAMES, L. F., MAYLAND, H. F., STEGELMEIER, B. L., AND KECHELE, P. O. (1996). Fundam. Appl. Toxicol. 32, 217-223. Selenium is an essential micronutrient, although ingestion in excess in pigs can cause disease conditions including neurological dysfunction and chronic skin and hoof lesions. Controlled feeding trials in growing swine, using the same Se content in feed sources, resulted in higher concentrations (p =£ 0.05) of Se in blood and organs of pigs fed seleno-DL-methionine compared with those receiving Astragalus bisulcatus or sodium selenate. Clinical signs of Se toxicity including neurological signs of paralysis were more severe and occurred sooner in the A. bisulcatus group than in the sodium selenate or seleno-DL-met hionine groups. All five pigs fed A. bisulcatus developed neurological signs of paralysis, and in four the signs occurred within 5 days of the start of treatment. Four of five pigs fed sodium selenate also developed paralysis, but this occurred 4 to 21 days after treatment began. The fifth pig in the group developed signs of chronic selenosis. Two of five pigs fed seleno-DL-methionine developed paralysis on 9 and 24 days, respectively, and the remaining three developed chronic selenosis. Selenium fed to pigs in three forms [plant (A. bisulcatus), sodium selenate, or seleno-DL-methionine] resulted in neurological dysfunction and lesions of symmetrical poliomyelomalacia. These were most severe in the A. bisulcatus group, which also had Polioencephalomalacia. Although seleno-DL-methionine caused the greater increase in tissue and blood Se concentrations, this did not correlate with severity of pathological changes, since animals fed A. bisulcatus developed more severe and disseminated lesions. Field observation and experimental trials in the United States have shown a great variety of syndromes and pathology resulting from ingestion of certain species of Astragalus by livestock. The syndromes include disease conditions induced by the nitro-containing Astragalus (A. miser), the swainsonine-containing Astragalus (A. lentiginosus, locoweeds), and the selenium-containing Astragalus (A. bisulcatus). These syndromes have been reviewed by James et al. (1981). Two Se-accumulating plants (A. bisulcatus and A. praelongus) and inorganic Se compounds have been shown to produce neurological signs and microscopic lesions of focal symmetrical Polioencephalomalacia and poliomyelomalacia when fed to young pigs (Hartley et al., 1984). Both plant species also contain small amounts of swainsonine, an amannosidase inhibitor that causes the lesions and clinical syndrome known as locoism. This toxin might contribute to the development of lesions when animals are poisoned eating these plants. In previous studies of Se intoxication, organic Se was fed to growing pigs in the form of selenocystine . The animals failed to thrive and had varying degrees of hepatic fibrosis, but neither neurological signs nor histological lesions were seen in the central nervous system (Hartley et al., 1984). The biochemical parameters of some of these pigs have been reported (Baker et al., 1989). This report details additional trials including dosing with seleno-DL-methionine (organic form of Se) and a comparison of the resulting tissue Se and histological lesions with those seen in animals treated with sodium selenate (inorganic form of Se) or A. bisulcatus (nonprotein, water-soluble plant forms of Se) at the same Se dose.
K E Panter - One of the best experts on this subject based on the ideXlab platform.
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comparative toxicity of selenium from seleno dl methionine sodium selenate and astragalus bisulcatus in pigs
Toxicological Sciences, 1996Co-Authors: K E Panter, L F James, H F Mayland, W J Hartley, Bryan L Stegelmeier, P O KecheleAbstract:PANTER, K. E., HARTLEY, W. J., JAMES, L. F., MAYLAND, H. F., STEGELMEIER, B. L., AND KECHELE, P. O. (1996). Fundam. Appl. Toxicol. 32, 217-223. Selenium is an essential micronutrient, although ingestion in excess in pigs can cause disease conditions including neurological dysfunction and chronic skin and hoof lesions. Controlled feeding trials in growing swine, using the same Se content in feed sources, resulted in higher concentrations (p =£ 0.05) of Se in blood and organs of pigs fed seleno-DL-methionine compared with those receiving Astragalus bisulcatus or sodium selenate. Clinical signs of Se toxicity including neurological signs of paralysis were more severe and occurred sooner in the A. bisulcatus group than in the sodium selenate or seleno-DL-met hionine groups. All five pigs fed A. bisulcatus developed neurological signs of paralysis, and in four the signs occurred within 5 days of the start of treatment. Four of five pigs fed sodium selenate also developed paralysis, but this occurred 4 to 21 days after treatment began. The fifth pig in the group developed signs of chronic selenosis. Two of five pigs fed seleno-DL-methionine developed paralysis on 9 and 24 days, respectively, and the remaining three developed chronic selenosis. Selenium fed to pigs in three forms [plant (A. bisulcatus), sodium selenate, or seleno-DL-methionine] resulted in neurological dysfunction and lesions of symmetrical poliomyelomalacia. These were most severe in the A. bisulcatus group, which also had Polioencephalomalacia. Although seleno-DL-methionine caused the greater increase in tissue and blood Se concentrations, this did not correlate with severity of pathological changes, since animals fed A. bisulcatus developed more severe and disseminated lesions. Field observation and experimental trials in the United States have shown a great variety of syndromes and pathology resulting from ingestion of certain species of Astragalus by livestock. The syndromes include disease conditions induced by the nitro-containing Astragalus (A. miser), the swainsonine-containing Astragalus (A. lentiginosus, locoweeds), and the selenium-containing Astragalus (A. bisulcatus). These syndromes have been reviewed by James et al. (1981). Two Se-accumulating plants (A. bisulcatus and A. praelongus) and inorganic Se compounds have been shown to produce neurological signs and microscopic lesions of focal symmetrical Polioencephalomalacia and poliomyelomalacia when fed to young pigs (Hartley et al., 1984). Both plant species also contain small amounts of swainsonine, an amannosidase inhibitor that causes the lesions and clinical syndrome known as locoism. This toxin might contribute to the development of lesions when animals are poisoned eating these plants. In previous studies of Se intoxication, organic Se was fed to growing pigs in the form of selenocystine . The animals failed to thrive and had varying degrees of hepatic fibrosis, but neither neurological signs nor histological lesions were seen in the central nervous system (Hartley et al., 1984). The biochemical parameters of some of these pigs have been reported (Baker et al., 1989). This report details additional trials including dosing with seleno-DL-methionine (organic form of Se) and a comparison of the resulting tissue Se and histological lesions with those seen in animals treated with sodium selenate (inorganic form of Se) or A. bisulcatus (nonprotein, water-soluble plant forms of Se) at the same Se dose.
Steven Christopher Loerch - One of the best experts on this subject based on the ideXlab platform.
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effects of dietary inclusion and naoh treatment of dried distillers grains with solubles on ruminal metabolism of feedlot cattle
Journal of Animal Science, 2012Co-Authors: T L Felix, T A Murphy, Steven Christopher LoerchAbstract:Dried distillers grains with solubles (DDGS) can decrease rumen pH because of their inherent acidity. Two replicated 4 × 4 Latin square experiments were conducted with ruminally fistulated heifers to determine the effects of dietary inclusion and NaOH treatment of DDGS on rumen metabolism. In Exp. 1, dietary treatments were 0%, 20%, 40%, or 60% DDGS on a DM basis. The remainder of the diet was 15% corn silage, 20% vitamin-mineral supplement, and corn (to replace DDGS) on a DM basis. Dry matter intake decreased (linear; P 0.05) of NaOH treatment by DDGS inclusion on VFA concentrations. Acetate concentration decreased (P = 0.04) in cattle fed 60% DDGS diets at 0 h, but at 3 h postfeeding it tended to increase (P = 0.06). Total lactate was less than 1.30 for all dietary treatments at all time points. Treating DDGS with 2% NaOH may increase rumen pH and decrease H(2)S, thereby alleviating Polioencephalomalacia.
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effects of haylage and monensin supplementation on performance carcass characteristics and ruminal metabolism of feedlot cattle fed diets containing 60 dried distillers grains
Journal of Animal Science, 2011Co-Authors: T L Felix, Steven Christopher LoerchAbstract:The objectives of this research were to determine the interaction of monensin and haylage sup- plementation for steers fed 60% dried distillers grains (DDGS) on 1) mineral status, performance, and carcass characteristics, and on 2) ruminal pH, H 2S, and short- chain fatty acid concentrations. In Exp. 1, Angus-cross steers (n = 168; BW = 277 ± 67 kg) were blocked by BW and allotted in a 2 × 2 factorial arrangement of treatments to 24 pens. Dietary treatments were 1) 0 mg of monensin/kg of diet + 0% haylage, 2) 33 mg of monensin/kg of diet + 0% haylage, 3) 0 mg of mo- nensin/kg of diet + 10% haylage, and 4) 33 mg of mo- nensin/kg of diet + 10% haylage. The remainder of the diet was 60% DDGS, 10% corn silage, 15% supple- ment, and corn (either 5 or 15%) on a DM basis. When supplemented with 0 mg of monensin/kg of diet, added haylage increased ADG by 5.7%, whereas when sup- plemented with 33 mg of monensin/kg of diet, added haylage increased ADG by 13% (P 0.05) on plasma mineral concentrations were observed; however, over time, plasma Cu concen- trations decreased (P < 0.01), whereas plasma ceru- loplasmin and S concentrations increased (P < 0.01). There were no treatment effects (P ≥ 0.08) on carcass characteristics. Cattle fed the 60% DDGS diets benefit- ted from increased dietary forage, and the effects of monensin and forage were additive for ADG and final BW. In Exp. 2, ruminally fistulated steers (n = 8; BW = 346 ± 34 kg) were used in a replicated 4 × 4 Latin square design and were randomly assigned to the diets used in Exp. 1. Haylage inclusion increased ruminal pH from 1.5 through 12 h postfeeding, and the effects of monensin supplementation were additive (P < 0.05). From 1.5 through 9 h postfeeding, steers fed 33 mg of monensin/kg of diet tended to have reduced (P ≤ 0.10) concentrations of H2S when compared with steers fed 0 mg of monensin/kg of diet. Acetate:propionate ratios at 6 h postfeeding were 0.94, 0.93, 1.29, and 1.35 for diets 1 to 4, respectively (P < 0.01); total lactate was decreased regardless of treatment (range: 0.94 to 1.42 μmol/mL). Sulfuric acid in DDGS, not ruminal short- chain fatty acids, may be responsible for the low rumen pH observed and may influence the maximum inclusion of DDGS in cattle diets. Monensin supplementation de- creased H2S concentration and may decrease the risk of Polioencephalomalacia for cattle fed high-DDGS diets.
M. D. Stern - One of the best experts on this subject based on the ideXlab platform.
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effects of dietary roughage and sulfur in diets containing corn dried distillers grains with solubles on hydrogen sulfide production and fermentation by rumen microbes in vitro
Journal of Animal Science, 2016Co-Authors: E Binversie, G I Crawford, M Ruizmoreno, A J Carpenter, Alfredo Dicostanzo, Bradley J Heins, M. D. SternAbstract:: Dried distillers grains with solubles (DDGS) have been used in production animal diets; however, overuse of DDGS can cause toxic concentrations of ruminal hydrogen sulfide gas (HS), resulting in Polioencephalomalacia, a deleterious brain disease. Because HS gas requires an acidic rumen environment and diet can influence ruminal pH, it has been postulated that dietary manipulation could help mitigate HS production. The objective of this study was to assess the effect of dietary roughage and sulfur concentrations on HS production and rumen fermentation. In Exp. 1, 7 dual-flow continuous culture fermenters were used in 4 consecutive 9-d periods consisting of 6 d of adaptation followed by 3 d of sampling. At the conclusion of each 9-d continuous culture period, adapted rumen fluid was used for inoculation of 24-h batch culture incubations for Exp. 2. For both experiments, 6 dietary treatments were formulated to consist of 0.3%, 0.4%, or 0.5% dietary sulfur (LS, MS, and HS, respectively) and 3% or 9% dietary roughage (LR and MR, respectively), using grass hay as the roughage source. A corn-based diet without DDGS was used as a control diet. Headspace gas was sampled to determine HS production and concentration. In Exp. 1, greater dietary roughage had no effect ( = 0.14) on HS production but did create a less acidic environment because of an increase ( < 0.01) in the in vitro pH. In Exp. 2, an increase in dietary sulfur caused an increase ( = 0.04) in ruminal HS production, but there was no direct effect ( = 0.25) of dietary roughage on HS production. Greater dietary roughage resulted in a less ( = 0.01) acidic final batch culture pH but a lower ( < 0.01) total VFA concentration. Further investigation is needed to determine a more effective way to mitigate ruminal HS production using dietary manipulation, which could include greater inclusion of dietary roughage or the use of different roughage sources.
Bryan L Stegelmeier - One of the best experts on this subject based on the ideXlab platform.
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comparative toxicity of selenium from seleno dl methionine sodium selenate and astragalus bisulcatus in pigs
Toxicological Sciences, 1996Co-Authors: K E Panter, L F James, H F Mayland, W J Hartley, Bryan L Stegelmeier, P O KecheleAbstract:PANTER, K. E., HARTLEY, W. J., JAMES, L. F., MAYLAND, H. F., STEGELMEIER, B. L., AND KECHELE, P. O. (1996). Fundam. Appl. Toxicol. 32, 217-223. Selenium is an essential micronutrient, although ingestion in excess in pigs can cause disease conditions including neurological dysfunction and chronic skin and hoof lesions. Controlled feeding trials in growing swine, using the same Se content in feed sources, resulted in higher concentrations (p =£ 0.05) of Se in blood and organs of pigs fed seleno-DL-methionine compared with those receiving Astragalus bisulcatus or sodium selenate. Clinical signs of Se toxicity including neurological signs of paralysis were more severe and occurred sooner in the A. bisulcatus group than in the sodium selenate or seleno-DL-met hionine groups. All five pigs fed A. bisulcatus developed neurological signs of paralysis, and in four the signs occurred within 5 days of the start of treatment. Four of five pigs fed sodium selenate also developed paralysis, but this occurred 4 to 21 days after treatment began. The fifth pig in the group developed signs of chronic selenosis. Two of five pigs fed seleno-DL-methionine developed paralysis on 9 and 24 days, respectively, and the remaining three developed chronic selenosis. Selenium fed to pigs in three forms [plant (A. bisulcatus), sodium selenate, or seleno-DL-methionine] resulted in neurological dysfunction and lesions of symmetrical poliomyelomalacia. These were most severe in the A. bisulcatus group, which also had Polioencephalomalacia. Although seleno-DL-methionine caused the greater increase in tissue and blood Se concentrations, this did not correlate with severity of pathological changes, since animals fed A. bisulcatus developed more severe and disseminated lesions. Field observation and experimental trials in the United States have shown a great variety of syndromes and pathology resulting from ingestion of certain species of Astragalus by livestock. The syndromes include disease conditions induced by the nitro-containing Astragalus (A. miser), the swainsonine-containing Astragalus (A. lentiginosus, locoweeds), and the selenium-containing Astragalus (A. bisulcatus). These syndromes have been reviewed by James et al. (1981). Two Se-accumulating plants (A. bisulcatus and A. praelongus) and inorganic Se compounds have been shown to produce neurological signs and microscopic lesions of focal symmetrical Polioencephalomalacia and poliomyelomalacia when fed to young pigs (Hartley et al., 1984). Both plant species also contain small amounts of swainsonine, an amannosidase inhibitor that causes the lesions and clinical syndrome known as locoism. This toxin might contribute to the development of lesions when animals are poisoned eating these plants. In previous studies of Se intoxication, organic Se was fed to growing pigs in the form of selenocystine . The animals failed to thrive and had varying degrees of hepatic fibrosis, but neither neurological signs nor histological lesions were seen in the central nervous system (Hartley et al., 1984). The biochemical parameters of some of these pigs have been reported (Baker et al., 1989). This report details additional trials including dosing with seleno-DL-methionine (organic form of Se) and a comparison of the resulting tissue Se and histological lesions with those seen in animals treated with sodium selenate (inorganic form of Se) or A. bisulcatus (nonprotein, water-soluble plant forms of Se) at the same Se dose.