Effects of Selenium Administration on Erythrocyte and Blood Plasma Glutathione Peroxidase Activity in Goats

The activity of glutathione peroxidase (GSH-Px, E.G. 1.11.1.9.) was determined in heparinized whole blood, blood plasma and washed erythrocytes from goats before and up to 4 weeks after the administration of selenium (0.4 mg/10 kg BW) and vitamin E (20 mg/10 kg BW) or only vit. E (20 mg/10 kg BW). It was found that Se administration caused a significant increase in enzyme activity in whole blood and washed erythrocytes first detected 2 weeks after the intramuscular injection of Se. No changes were observed in plasma from the treated animals. Minor and insignificant changes were seen in the vit. E treated control animals. It is concluded that GSH-Px activity in blood plasma or serum is of no value as a short-term indicator of the selenium status of goats but whole blood is a good indicator of the long-term status.     

Glutathione Peroxidase Activity and Erythrocyte Lipid Peroxidation as Indices of Selenium and Vitamin E Status in Young Pigs

A randomized, blocked 2³ factorial experiment was conducted with 48 pigs from sows fed a diet low in selenium and vitamin E. From 3 to 12 weeks of age the piglets were kept in single pens and fed a basic diet consisting mostly of barley, dried skim milk, soybean meal and dried yeast, and containing 55 µg selenium and 3 mg vitamin E per kg. The treatment factors — i.e. feed supplements — were 2 levels of Se (nil, 60 µg/kg), 2 levels of vitamin E (nil, 50 mg/kg), and 2 levels of the feed antioxidant ethoxyquin (nil, 150 mg/kg). Blood samples, collected at termination of the experiment, were examined for glutathione peroxidase activity (GSH-Px) and resistance against erythrocyte lipid peroxidation (ELP) to evaluate Se and vitamin E status, respectively. Analysis of variance showed the GSH-Px activity to be litter-dependent (P < 0.001) and influenced by selenium supplementation (P < 0.001) but not by the other supplements or by interactions between supplements. Resistance against ELP was influenced only by vitamin E supplementation (P < 0.001). GSH-Px and ELP thus seem to be valuable and simple methods for evaluating, respectively, Se status and vitamin E status in growing pigs.     

饲粮锌、硒和维生素E水平对经产母猪繁殖性能及相关参数的影响

选择年龄、体重、胎次、繁殖性能较一致的二元杂经产母猪 (长白×约克 ) 2 7头 ,采用 L9( 34 )正交表安排试验 ,共 9个试验组 ,每组 3个重复。饲粮锌、硒和维生素 E均设置 3个水平 :锌 4 5、85、12 5 m g/ kg;硒 0 .10、0 .2 5、0 .4 0 mg/ kg;维生素 E15、30、4 5 IU/ kg。研究了饲粮微量养分锌、硒和维生素 E对经产母猪相关参数的影响规律。结果表明 :( 1)饲粮中含锌量 85 mg/ kg、含硒量 0 .4 0 m g/ kg、含维生素 E量 4 5 IU / kg时 ,可以获得最多的窝产仔数 ( P<0 .10 ) ,分别为( 10 .3± 1.0 )头、( 10 .2± 1.2 )头、( 10 .3± 1.0 )头 ;母猪断奶返情时间间隔也最短 ( P<0 .0 5 )。 ( 2 )经产妊娠母猪血清雌激素浓度在妊娠期保持相对高水平 ;孕激素妊娠前期保持相对高水平 ,后期则保持相对低水平 ,是发挥母猪繁殖潜力的保证。 ( 3)经产母猪喂给含锌量 85 mg/ kg、含硒量 0 .4 0 mg/ kg、含维生素 E量 4 5 IU/ kg的饲粮时 ,血清总蛋白含量最高 ( P<0 .10 ) ,血清尿素浓度最低 ( P<0 .10 ) ,提示有更多的蛋白质在母体和胎儿累积。 ( 4 )血清 GSH- Px活力妊娠后期比妊娠前期低 ,提示妊娠后期比妊娠前期母体和胎儿代谢过程产生的过氧化物更多。综合所考察的参数显示 ,经产母猪饲粮中含锌 85 mg/ kg、     

Glutathione Peroxidase Activity,Plasma Total Antioxidant Capacity,and Urinary F2‐ Isoprostanes as Markers of Oxidative Stress in Anemic Dogs

Background

Oxidative stress plays a role in the pathophysiology of several diseases and has been documented as a contributor to disease in both the human and veterinary literature. One at‐risk cell is the erythrocyte, however, the role of oxidative stress in anemia in dogs has not been widely investigated.

Hypothesis/Objective

Anemic dogs will have an alteration in the activity of glutathione peroxidase (GPx), a decrease in of total antioxidant capacity (TAC), and an increased concentration of urinary 15‐F₂‐isoprostanes (F₂‐IsoP) when compared to healthy dogs.

Animals

40 client‐owned dogs with anemia (PCV <30%) age‐matched to 40 client‐owned healthy control dogs.

Methods

Prospective, cross‐sectional study. Whole blood GPx activity, plasma TAC, and urinary F₂‐isoprostane concentrations were evaluated in each dog and compared between groups.

Results

Anemic dogs had significantly lower GPx activity (43.1 × 10³ +/‐ 1.6 × 10³ U/L) than did dogs in the control group (75.8 × 10³ +/‐ 2.0 × 10³ U/L; P < 0.0001). The GPx activity in dogs with hemolysis (10³ +/‐ 0.8 × 10³ U/L) was not significantly different (P = 0.57) than in dogs with nonhemolytic anemia (43.5 × 10³ +/‐ 1.1 × 10³ U/L). The TAC concentrations (P = 0.15) and urinary F₂‐isoprostanes (P = 0.73) did not significantly differ between groups.

Conclusions and Clinical Importance

Glutathione peroxidase activity was significantly decreased in anemic dogs indicating oxidative stress. Additional studies are warranted to determine if antioxidant supplementation would improve survival and overall outcome as part of a therapeutic regimen for anemic dogs.     

不同饲粮氨基酸水平对泌乳母猪生产性能、血液指标及乳汁中氨基酸浓度的影响

本试验旨在研究理想氨基酸模型下,不同饲粮氨基酸水平对泌乳母猪生产性能、血液指标及乳汁中氨基酸浓度的影响.选用200头体况、分娩时间相近的长白×约克夏杂交母猪,随机分成4组,每组设50个重复,每个重复1头母猪,分别饲喂总赖氨酸水平为0.9%(试验组1)、1.0%(试验组2)、1.1%(试验组3)和1.2%(试验组4)的饲粮,并通过添加5种合成氨基酸保证4组饲粮中可消化赖氨酸:可消化缬氨酸:可消化苏氨酸:可消化含硫氨基酸:可消化色氨酸的值(100:85:66:60:19)一致.结果表明:试验组2仔猪断奶窝增重分别比试验组1和试验组4提高了4.48%和4.34%(P<0.01),仔猪平均日增重分别比试验组1和试验组4提高了5.46%和4.74%(P<0.01);试验组2背膘厚损失比试验组4多0.57 mm(P<0.05);试验组2血浆尿素氮浓度显著低于其他处理(P<0.05);试验组2血浆赖氨酸、苏氨酸、缬氨酸、蛋氨酸、异亮氨酸、瓜氨酸、谷氨酸、甘氨酸(P<0.01)和亮氨酸(P<0.05)浓度均极显著或显著低于试验组4,除赖氨酸和苏氨酸浓度与试验组1差异显著(P<0.05)外,以上其他氨基酸浓度与试验组1、试验组3差异不显著(P>0.05);试验组2血浆中总氨基酸浓度显著或极显著低于其他组(P<0.05或P<0.01),乳汁中赖氨酸浓度极显著低于试验组4(P<0.01),与试验组1、试验组3差异不显著(P>0.05),且缬氨酸(P<0.05)、异亮氨酸(P<0.05)、亮氨酸(P>0.05)、丙氨酸(P>0.05)、酪氨酸(P>0.05)和谷氨酸(P>0.05)浓度以试验组2最高.由此可知,理想氨基酸模型下,泌乳母猪赖氨酸摄入量为59 g/d(饲粮赖氨酸水平为1.0%)时,能够获得最高的氨基酸利用率和最好的生产性能.     

Clinico-Pathologic Findings in Young Pigs Fed Different Levels of Selenium,Vitamin E and Antioxidant

A randomized, blocked 2³ factorial experiment was conducted with 48 young pigs. The treatment factors were: 2 levels of selenium (55 and 115 µg/kg), 2 levels of vitamin E (3 and 53 mg/kg) and 2 levels of the antioxidant feed additive Ethoxyquin (0 and 150 mg/kg). All pigs were kept in single pens and fed ad libitum throughout the experimental period of 9 weeks, i.e. from 3 to 12 weeks of age.Plasma, heart, liver and muscle Se levels as well as whole blood glutathione peroxidase activity (EC 1.11.1.9 GSH-Px) were significantly higher in pigs given a dietary supplement of Se than in pigs given no supplement of Se (P ≤ 0.001). The Se-supplemented pigs showed a tendency to lower mean serum transaminase activity (ASAT and ALAT) than unsupplemented pigs, but the influence was significant (P ≤ 0.05) only for the ALAT activity.Blood vit. E levels were higher for pigs receiving a supplement of vit. E than for unsupplemented pigs (P ≤ 0.001), and so was the resistance of red blood cells against lipid peroxidation (ELP), as expressed by lower ELP values.There were no effects of Ethoxyquin supplementation on the biochemical variables included in the study.The histological examination of heart muscle showed that the score for changes was negatively influenced by both Se and vit. E supplement (P ≤ 0.001) and to some extent also by Ethoxyquin supplement (P ≤ 0.05). The histological picture of m. long dorsi was influenced only by the vit. E supplement (P ≤ 0.01). No histological changes were found in the liver in this study. There were inverse relationships between whole blood GSH-Px defluorescence time and blood Se, and between ELP and whole blood vit. E (P ≤ 0.001).