首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 15 毫秒
1.
The effects of long-term consumption of 1 and 5 ppm of Cd on Cd, Cu, Fe, and Zn concentrations in milk and a variety of tissues of first-lactation dairy cows was investigated. Thirty-six Holstein heifers were allocated to three groups and fed similar diets differing only in the concentration of Cd (.25, 1, and 5 ppm) for a 394-d period before calving. One- and 5-ppm Cd concentrations were achieved using CdCl2. Liver, kidney cortex, and muscle were biopsied from one-half of the heifers of each group before Cd supplementation and again from the same heifers within 5 d after parturition. Colostrum and milk were sampled throughout the 150 d of lactation. Urine was sampled after an average of 450 d of Cd exposure. At slaughter (after an average of 554 d), 11 tissues were sampled from 12 cows representing all treatment groups. During the first 394 d, Cd accumulated in kidney and liver with increasing dietary concentrations of Cd but did not further increase by 554 d. However, by 554 d Cd had also accumulated in the adrenal glands, ovaries, spleen, and uteri of cows consuming 5 ppm of Cd. Dietary Cd did not influence the concentration of Cd, Cu, Fe, or Zn in colostrum or milk. However, urine pH, Zn, and K were lower in cows consuming 5 ppm of Cd. Liver Cu was reduced by 1 and 5 ppm of Cd at both 394 and 554 d.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

2.
Two experiments were conducted to study effects of high-level Cu supplementation on measures of Cu status and forage utilization in beef cattle. In Exp. 1, eight steers randomly received an intraruminal bolus containing 12.5 g of CuO needles (n = 4) or no bolus (n = 4). Steers were individually offered free-choice ground limpograss (Hemarthria altissima) hay. On d 12 (Period 1) and d 33 (Period 2) steers were placed in metabolism crates, and total forage refused and feces produced were collected for 7 d. Daily samples of forage offered and refused and of feces excreted for each steer within period were analyzed for DM, ash, NDF, ADF, and CP. Liver biopsies were collected on d 0, 12, and 33. Copper oxide bolus administration resulted in greater (P < 0.03) liver Cu (DM basis) accumulation in Period 1 (556 vs. 296 mg/kg) and Period 2 (640 vs. 327 ppm). Apparent digestibilities of NDF and CP were greater (P < 0.04) for steers receiving no bolus in Period 2 (62.2 vs. 57.1% and 50.2 vs. 43.4% for NDF and CP digestibility, respectively). In Exp. 2, 24 crossbred heifers were assigned to individual pens and received a molasses-cottonseed meal supplement fortified with 0, 15, 60, or 120 ppm of supplemental Cu (Cu sulfate; six pens per treatment). All heifers were offered free-choice access to ground stargrass (Cynodon spp.) hay. Heifer BW and liver biopsies were collected on d 0, 42, and 84. Forage refusal was determined daily, and diet DM digestibility was estimated over a 21-d period beginning on d 42. Heifers consuming 120 ppm of supplemental Cu gained less (P < 0.05; 0.04 kg/d) than heifers consuming 15 (0.19 kg/d) and 60 ppm of Cu (0.22 kg/d), but their ADG did not differ from that by heifers consuming no supplemental Cu (0.14 kg/d; pooled SEM = 0.07). Heifers supplemented with 15 ppm of Cu had greater (P < 0.05) liver Cu concentrations on d 84 than those on the 0-ppm treatment and the high-Cu treatments (60 and 120 ppm). Forage intake was less (P = 0.07) by heifers receiving no supplemental Cu than by heifers on all other treatments (6.6 vs. 5.8 +/- 0.37 kg/d). Apparent forage digestibility was not affected by Cu treatment. These data suggest that high rates of Cu supplementation (Cu sulfate; > 60 ppm of total Cu) resulted in less liver Cu accumulation by beef heifers compared with heifers consuming diets supplemented with moderate dietary Cu concentrations (i.e., 15 ppm). As well, the administration of CuO boluses might depress the digestibility of forage nutrient fractions in steers.  相似文献   

3.
The metabolism of a single oral zinc-65 dose was studied in young dairy calves fed two concentrations of added A1 (0 and .20% A1) and two concentrations of added P (0 and .22% P) for 7 wk. The four treatments were 1) normal P-low A1, 2) low P-low A1, 3) normal P-high A1 and 4) low P-high A1. The basal diet (low P-low AL) contained, by analysis, .132% P, .74% Ca, .021% A1 and 59 ppm Zn. Zinc-65 absorption was greater (66.5 vs 63.2% of dose, P less than .10) with the low-P diet; added A1 reduced (P less than .05) 65Zn absorption. Calves fed low-P diets had higher (P less than .10) concentrations of 65Zn in liver, kidney, spleen, heart, small intestine and testicle than those fed normal-P diets. Zinc-65 was reduced (P less than .10) in pancreas, heart, testicle and muscle of calves fed high A1. Iron was increased in liver and kidney (P less than .10), Zn (P less than .10) and Mn (P less than .01) were increased in liver, but Fe in small intestine and Cu in muscle and tibia shaft were decreased (P less than .10) in calves fed the low-P diets compared to those fed adequate-P diets. High A1 reduced (P less than .10) Cu in small intestine and tibia shaft. The results suggest that zinc metabolism may be moderately affected in calves fed either low-P or high-A1 diets.  相似文献   

4.
The objectives were to determine if strategic supplementation of range cows with a long-acting (6 mo), trace mineral, reticulorumen bolus containing Cu, Se, and Co would: (1) increase cow BCS and BW, and calf birth, weaning, and postweaning weights, or weight per day of age (WDA); (2) increase liver concentrations of Cu or Zn in cows, or blood Se, Cu, or Zn concentrations in cows and calves; and (3) vary by cow breed for any of these response variables. There were 192 control and 144 bolused Composite cows (C; 25% Hereford, Angus, Gelbevieh, and Senepol or Barzona); 236 control and 158 bolused Hereford (H) cows; and 208 control and 149 bolused Brahman cross (B) cows used in a 3-yr experiment. Cows were weighed and scored for body condition in January, May, and September, and all bolused cows received boluses in January. Each year, from among the 3 breed groups a subset of 15 control and 15 bolused cows (n = 90) had samples obtained in January and May for liver Cu and Zn, blood Se, and serum Cu and Zn. As for cows, blood and serum from the calves of these cows were sampled each year in May and September for Cu, Se, and Zn. There was a significant breed x year x treatment interaction (P = 0.001) for cow weight loss from January to May. Calf WDA, weaning, and postweaning weights did not differ (P > 0.40) between bolused and control cows, but there was a significant (P = 0.022) breed x year x treatment interaction for birth weight. Liver Cu was deficient (< 75 ppm; P < 0.001) in control cows and adequate (< 75 to 90 ppm) for bolused cows. Liver Cu differed by year (P < 0.001). Blood Se was adequate (< 0.1 ppm) for all cows except in January 2001 and 2002. There was no difference (P > 0.50) in blood Se between treatment groups in January, but bolused cows had greater (P < 0.01) blood Se in May. Breed differences for blood Se concentrations existed for bolused cows, with B having greater (P < 0.05) blood Se than either C or H cows. Breed differences also existed for control cows, with H having less blood Se (P < 0.04) than B or C cows. Calves from bolused cows had greater blood Se than calves from control cows (P = 0.01). Supplementation via a long-acting trace mineral bolus was successful in increasing liver Cu in cows and blood Se in cows and calves, but the responses varied by year. Bolus administration had variable effects on BW change in early lactation, depending on breed and year, which may indicate the need for breed- and year-specific supplementation programs.  相似文献   

5.
Oxidized copper wire, commonly referred to as copper oxide needles (CuON), was evaluated using purebred Hereford cows and their calves. Thirty-seven cows were allocated to Cu treatments of 0, 25 or 50 g CuON (79.9% Cu in CuON) with 12, 12 and 13 cows per treatment, respectively; calves within cow treatments were allocated to treatment of 0 and 20 g CuON. Single oral doses of CuON were given at the start of a grazing trial that lasted 92 d. Cows and calves were weighed and blood samples were taken on d 0, 28, 63 and 92; liver biopsies were taken on d 0, 28 and 92 of the grazing trial. Cattle were consuming grass forage with mean concentrations on d 0, 28, 63 and 92 of the grazing trial ranging from 1.6 to 5.5 mg/kg DM for Cu, 2.5 to 5.5 mg/kg DM for Mo and 1.3 to 1.5 g/kg DM for total S. The water consumed by cattle contained 947 mg sulfate per liter (SE = 13.2, n = 4). Body weight of cows and calves was not influenced (P greater than .05) by CuON. Liver Cu was higher (P less than .01) in treated cows and calves but was not different (P greater than .05) between cows dosed with 25 or 50 g CuON. Treatment of cows and calves with CuON had no influence (P greater than .05) on the concentration of Fe or Mo in liver or plasma, the concentration of Cu and ceruloplasmin activity in plasma, or the concentration of Zn in liver. Plasma Zn did not differ (P greater than .05) in cows, but it was higher (P less than .05) in the calves suckling cows treated with CuON. It was concluded that dosing cows and calves with CuON resulted in a higher Cu content of liver but did not adversely influence the metabolism of Fe or Zn or modify the concentration of Mo in the plasma or liver of cows or calves.  相似文献   

6.
Fetal fluid, diaphragm muscle, heart, kidney, and liver from 14 four- to five-month-old calf fetuses were analyzed for Zn, Cu, Cd, Cr, Ni, Pb, and Fe. The same tissues and bone were examined from postparturient calves 30, 60, and 120 days of age. Weaned calves (8 to 9 months old) were necropsied and diaphragm muscle, heart, kidney, liver, brain, and bone were analyzed. Additional calves from cows exposed or not exposed to anaerobically digested sludge were placed in a feed yard at weaning for a feeding period of 150 days and then were killed and necropsied. Heavy metal content of the aforementioned tissues was compared with the same tissues obtained from peer calves weaned, killed, and necropsied 150 days earlier. Zinc, Cu, and Fe were up to 11 times higher in fetal livers than in control or exposed postparturient calves. These concentrations declined after birth and stabilized at approximately the concentrations observed in adult cattle at about 12 to 14 months of age. Cadmium accumulated to a greater extent in kidneys and livers of exposed calves than in control calves. However, the accumulation did not produce a detectable effect upon the functional or morphologic characteristics of the organs examined. Other metals were present at low levels and were generally not remarkably different in control and exposed animals.  相似文献   

7.
本研究通过在精饲料中添加蒙脱石喂养杂交牛的方法,探讨蒙脱石对动物体内必需微量元素铜、铁、锌及有害元素镉、铅含量的影响。结果表明:与对照相比,喂蒙脱石的杂交牛日增重提高了14.96%(P<0.01),饲料转化率提高了9.22%(P<0.05);肾脏和脾脏中铅含量显著增加(P<0.05),肾脏、肝脏、脾脏和肠中镉的含量极显著增加(P<0.01),而血液中镉含量显著降低(P<0.01),其余组织中镉和铅的含量变化不显著;脾脏铜和铁含量极显著减少(P<0.01),肾脏中锌含量极显著增加(P<0.01),肝脏和肌肉组织中铁含量显著增加(P<0.05),其余各组织中的变化不显著(P>0.05)。结论:在饲料中添加蒙脱石,可在不同程度上改变铅、镉、铜、锌、铁在动物体内各器官和组织中的分布水平,但不能有效降低肉牛各组织中铅、镉的蓄积。  相似文献   

8.
饲粮添加铜、铁和锌对牛组织和血液铅和镉含量的影响   总被引：1，自引：0，他引：1  
本研究旨在探讨饲粮添加必需微量元素铜、铁和锌对肉牛组织和血液铅和镉含量的影响。选用 ２０头 １２月龄肉牛,随机分为 ２组,每组 １０头,各组分别饲喂基础精饲料（对照组）和基础精饲料中添加铜 ２０ｍｇ、铁 ２００ｍｇ和锌 ２００ｍｇ的试验精饲料（试验组）,粗饲料自由采食。试验期为 １５０ｄ。每天以组为单位计算牛的采食量;每 ３０ｄ称取牛体重并采集血液样品,试验结束后,屠宰试验牛,采集肾脏、肝脏、心脏、胰脏、脾脏、瘤胃、大肠及背肌组织样品,测定血液和组织中铅和镉含量。结果表明：牛精饲料中添加铁、铜和锌后,平均日增重极显著地提高了１２．５０％（Ｐ＜０．０１）,料重比极显著地降低了 １５．６８％（Ｐ＜０．０１）;铅含量在胰脏和瘤胃中极显著增加（Ｐ＜０．０１）,在脾脏和血液中显著减少（Ｐ＜０．０５）,在其余组织中无显著变化（Ｐ＞０．０５）,铅蓄积的器官主要是胃;镉含量在肾脏、肝脏、脾脏、瘤胃和大肠中均极显著增加（Ｐ＜０．０１）,但心脏中的镉含量极显著降低（Ｐ＜０．０１）,镉蓄积的器官主要是肾脏。结果提示,在饲粮中添加铜、铁和锌可以改善肉牛的生长性能,但不能有效减少脏器及肌肉组织中铅和镉的蓄积。  相似文献   

9.
Two studies were conducted to evaluate the availability of dietary Cu offered to growing beef cattle consuming molasses-based supplements. In Exp. 1, 24 Braford heifers were assigned randomly to bahiagrass (Paspalum notatum) pastures (two heifers/pasture). Heifers were provided 1.5 kg of TDN and 0.3 kg of supplemental CP/heifer daily using a molasses-cottonseed meal slurry. Three treatments were randomly assigned to pastures (four pastures/treatment), providing 100 mg of supplemental Cu daily in the form of either CuSO4 (inorganic Cu) or organic-Cu. A third treatment offered no supplemental Cu (negative control). Heifer BW was collected at the start and end of the study. Jugular blood and liver samples were collected on d 0, 29, 56, and 84. In Exp. 2, 24 Brahman-crossbred steers were fed the same molasses-cottonseed meal supplement at the same rates used in Exp. 1. Steers were housed in individual pens (15 m2) with free-choice access to stargrass (Cynodon spp.) hay. Four Cu treatments were assigned to individual steers (six pens/treatment) providing 1) 10 ppm of Cu from an organic source; 2) 10 ppm Cu from Tri-basic Cu chloride (TBCC); 3) 30 ppm of Cu from TBCC; or 4) 30 ppm of Cu, a 50:50 ratio of TBCC and organic Cu. Body weights and jugular blood and liver samples were collected on d 0, 24, 48, and 72. In Exp. 1, liver Cu concentrations did not differ between heifers supplemented with inorganic and organic Cu. Each source resulted in increased (P < 0.05) liver Cu concentrations compared with the unsupplemented control. Plasma ceruloplasmin concentrations were higher (P < 0.05) for Cu-supplemented heifers, independent of Cu source. Heifer ADG tended (P = 0.11) to increase with Cu supplementation compared with the unsupplemented control. In Exp. 2, liver Cu was greater (P < 0.05) on d 24, 48, and 72 for steers consuming 30 vs. 10 ppm of Cu. Steers supplemented with organic Cu had lower DMI than steers supplemented with 10 or 30 ppm of TBCC. These data suggest that the inorganic and organic Cu sources evaluated in these studies were of similar availability when offered in molasses supplements. A dietary Cu concentration greater than 10 ppm might be necessary to ensure absorption in beef cattle fed molasses-based supplements.  相似文献   

10.
Two studies were conducted to compare the availability of trace minerals offered to Brahman-crossbred heifers in either grain- or molasses-based supplements. Heifers were randomly assigned to bahiagrass pastures of equal size (n = 3 and 2 heifers/ pasture with 6 and 4 pastures/treatment for Experiment 1 and 2, respectively). Two supplements were formulated using corn and cottonseed meal (DRY) or molasses and cottonseed meal (LIQ). In Experiment 2, a third treatment consisted of the DRY supplement with additional S to equal the amount naturally supplied by the LIQ treatment (DRY+S). Supplements were formulated to provide, on average, 1.5 kg of TDN and 0.3 kg of CP/heifer daily and were fed three times weekly. Supplements also were fortified to provide 140, 76, and 63 mg of Cu, Mn, and Zn per heifer daily. Individual heifer weights were collected at the start and conclusion of the study, following a 12-h shrink. Plasma ceruloplasmin and liver Cu, Mn, Mo, Fe, and Zn concentrations were determined on d 0, 29, 56, and 84 in Experiment 1, and d 0, 32, 57, and 90 in Experiment 2. No differences were detected in heifer BW change (-9.3 and -7.3 kg for DRY and LIQ in Experiment 1, and 51.7, 46.3, and 46.7 kg for DRY, DRY+S, and LIQ in Experiment 2, respectively). In both experiments, liver Fe, Mn, and Zn concentrations were not affected by supplement treatment. Molybdenum tended (P = 0.06 and 0.10 for Experiments 1 and 2, respectively) to accumulate in the liver of heifers fed molasses-based supplements. In Experiment 1, Cu accumulation was less (P < 0.001) in heifers fed the liquid supplements (271 vs 224, 286 vs 202, and 330 vs 218 ppm, for DRY and LIQ supplements on d 29, 56, and 84, respectively). In Experiment 2, heifers receiving Cu from DRY supplements had a 155-ppm increase in liver Cu concentration, which was greater (P = 0.03) than DRY+S (87 ppm increase) and LIQ (P < 0.001; 13 ppm increase). Although lower than heifers receiving DRY, heifers receiving DRY+S had greater (P = 0.02) liver Cu concentrations than heifers receiving LIQ by the end of the study. In both experiments, plasma ceruloplasmin concentrations were highest (P < 0.04) in heifers receiving DRY supplement. The results of these studies suggest that components in molasses-based supplements decrease the accumulation of Cu in the liver of beef heifers. The S and Mo components of molasses may be responsible, at least in part, for this antagonism.  相似文献   

11.
试验旨在探明耐镉乳酸菌对蛋鸡的脏器系数、镉在蛋鸡组织及鸡蛋中的残留及钙、铁、锌、锰、铜和硒在组织和鸡蛋中沉积的影响。试验分为5组：对照组,饲喂基础日粮;镉组,基础日粮+5 mg/kg镉（以氯化镉的形式添加）;乳酸菌组,基础日粮+1×1010 CFU/kg耐镉乳酸菌;镉+低剂量乳酸菌组,基础日粮+5 mg/kg镉+1×1010 CFU/kg耐镉乳酸菌;镉+高剂量乳酸菌组,基础日粮+5 mg/kg镉+1×1011 CFU/kg耐镉乳酸菌,试验期6周。试验期末,采集各组蛋鸡血液,测定总抗氧化力（T-AOC）和超氧化物歧化酶（SOD）活力;采集各组蛋鸡内脏组织和鸡蛋,计算脏器系数,同时测定组织和鸡蛋中镉、钙、铁、铜、锌、锰及硒元素含量。结果显示,与对照组相比,镉及乳酸菌组显著提高了蛋鸡总抗氧化能力（P<0.05）。各处理组中,镉组脾脏指数最低,镉加乳酸菌组脾脏指数显著高于镉组（P<0.05）;与对照组相比,乳酸菌组显著提高心脏指数（P<0.05）。镉组致蛋鸡肝脏和肾脏中镉残留量远高于其他组织,补加耐镉乳酸菌显著减少了心脏的镉残留量（P<0.05）。与对照组相比,镉组显著降低肾脏钙、脾脏和卵黄的锰含量（P<0.05）;与对照组相比,镉加低剂量耐镉乳酸菌显著增加肾脏锰含量、卵黄铁含量及肾脏和脾脏铜含量（P<0.05）;镉在鸡蛋中的残留量较低,与对照组相比,镉组显著降低鸡蛋铁、锰元素含量（P<0.05）,补加耐镉乳酸菌显著增加铁、锌、锰和硒元素含量（P<0.05）。结果表明,在蛋鸡日粮中添加1×1010 CFU/kg的耐镉乳酸菌,可显著提高蛋鸡血清总抗氧化力水平和蛋鸡的心脏指数,显著改善镉暴露导致的脾脏萎缩和心脏镉的残留量;同时显著增加锰、铜、铁在肾脏、脾脏及卵黄中的含量及铁、锌、锰和硒在鸡蛋中的含量。  相似文献   

12.
Summary During a 98-day trial, eight groups of eight male weanling Texel x Friesian milk sheep lambs were fed the same hay and concentrates, the latter differing only in the contents of Cu, Zn, and Mo. At high (± 30 ppm) and moderately low (± 15 ppm) copper levels in the concentrates, additions of Zn (respectively 0, 150, and 340 ppm) and Mo (0 and 16 ppm) to the concentrates were studied with regard to effect on the accumulation of copper in the liver. At the higher copper level, the addition of 150 or 340ppm Zn resulted in a significant decrease of the Cu accumulation in the liver, while at a moderately low copper level the effect of these additions on the Cu accumulation was only slight. The two Zn doses given appeared to be equally effective in reducing the Cu accumulation. Additions of zinc did not increase liver and kidney Zn. The addition of Mo. resulted in higher levels of Mo in liver and kidney. At either copper level the addition of 16 ppm Mo was more effective in reducing the Cu accumulation in the liver than the addition of 150 or 340 ppm Zn. The additions of Zn and Mo, had no visible influence on the health of the lambs. This agrees with the finding that the blood parameters (determination of haemoglobin, haematocryt, protein, copper, zinc, enzymes) and the growth of the lambs were in the normal range. These results suggest that zinc may be a useful alternative to the somewhat toxic molybdenum as an additive to concentrates for sheep in preventing Cu intoxication.  相似文献   

13.
The relationship between serum minerals and stress and(or) disease has not been fully evaluated in beef cattle. Two trials were conducted to determine the changes in serum Cu and Zn during market-transit stress and(or) disease. Two additional trials were conducted to determine the changes in serum Cu and Zn after inoculation with infectious bovine rhinotracheitis virus (IBRV), with one of the trials determining the changes in serum Ca and P. Trials 1 (n = 80) and 2 (n = 100) utilized calves that were handled through a normal market-transit system and transported 1,967 km to the feedlot. Trials 3 (n = 37) and 4 (n = 8) used calves that were sero-negative to IBRV and then challenged with 2.7 x 10(5) plaque-forming units of the virus. Serum samples were collected at specified intervals and serum minerals were measured for each trial. Serum Zn for morbid or IBRV-challenged calves was decreased by 34, 57, 29 and 15% (P less than .05) for the four trials, respectively, at peak morbidity. Serum Cu of morbid or IBRV-challenged calves increased 5, 15, 40 and 33% for the four trials, respectively, at peak morbidity. Feed intakes were lower during morbidity for market-transit trials and after IBRV inoculation. Lower feed intake could partially explain the decrease in serum Zn; however, when feed intake was held constant, serum Zn concentration still decreased. Serum Zn decreased and serum Cu increased during market-transit morbidity or after IBRV.  相似文献   

14.
An outbreak of neonatal diarrhea occurred among beef calves (2000 animals) from one large Argentinian farm in 1985. Rotavirus was detected in 78% (106/136) and enterotoxigenic Escherichia coli in 1.5% of the samples (2/136) obtained from sick calves. In comparison rotavirus was identified in only 1.6% (1/63) of the samples from clinically healthy calves. The rotavirus strain responsible for the outbreak was characterized as serotype 6 belonging to group A. In the following three years the protective capacity of a combined rotavirus-E. coli inactivated vaccine administered to the dams during the last third of the gestation period was evaluated on this farm by comparison of morbidity due to diarrhea in calves from vaccinated vs. placebo cows within the same year. The morbidity due to diarrhea among calves from dams in the vaccinated and placebo groups was 34% and 77%, respectively in 1986; 23% and 47% in 1987, and 15% and 34%, in 1988. In 1987 morbidity of diarrhea in calves born from vaccinated heifers was 54% and 74% in calves from placebo heifers. In 1988 morbidity from diarrhea was 41% and 54%, respectively among calves in these two groups. In all experiments, calves from heifers showed significantly greater morbidity than calves from cows. Differences in diarrhea morbidity between the vaccinated and placebo groups were statistically significant (P less than 0.05). Additional studies showed that the diarrhea had a significant influence (P less than 0.05) on the average live weight of the calves at weaning (5 to 7 months) with an average weight loss of 7.8 kg per calf among the calves affected with diarrhea.  相似文献   

15.
Thirty 6-yr-old Targhee ewes were randomly allotted to one of five supplemental treatments to evaluate supplementation effects on liver and fecal Zn and Cu concentrations and serum alkaline phosphatase activity: 1) control, 2) Zn complex, 3) Zn and Cu (ZnCu) complex, 4) Zn sulfate, and 5) ZnCu sulfates. Supplements were administered daily in gelatin capsules for 56 d. Liver biopsies and serum samples were collected every 14 d starting on d 0. Supplemental Zn and Cu levels were formulated to provide 90 mg/kg Zn and 10 mg/kg Cu, respectively, on a daily dry matter intake basis. Form (complex vs sulfate) x type (Zn vs ZnCu) interactions were not detected (P > 0.35). Therefore, contrast statements were used to make the following treatment comparisons: 1) control vs supplement, 2) Zn vs ZnCu, and 3) complex vs sulfate. Ewe BW at the end of the study (P = 0.09) and ewe BW change from beginning to end of the study (P = 0.07) were greater for supplemented than control ewes. Body weight and BW change did not differ between sulfate and complex (P > 0.39) or Zn- and ZnCu- (P > 0.40) supplemented ewes. Liver Cu concentrations did not differ (P = 0.41) between control and supplemented ewes. Liver Cu concentrations were higher (P < 0.10) for ewes supplemented with ZnCu than Zn and complex than sulfate forms of supplement. Liver Zn concentration tended (P = 0.13) to be higher in ZnCu than Zn-supplemented ewes. Liver and fecal Zn concentration were higher (P < 0.06) in ewes fed complex than sulfate supplements. However, serum alkaline phosphatase activity tended (P = 0.12) to be greater in ewes fed sulfate than complex supplements. Supplementing mature ewes with complexed minerals resulted in higher concentrations of Zn and Cu in the liver. In addition, supplemental Cu tended to increase concentrations of Zn in the livers of ewes; however, high levels of supplemental Zn did not negatively impact liver Cu concentrations.  相似文献   

16.
Two experiments were conducted to determine whether the supplementation of Cu in the organic or inorganic form to 2-yr-old cows, before and after calving, affects reproduction rate, calf health and performance, passive transfer of immunoglobulin, or liver and serum Cu concentrations compared with unsupplemented controls. Cows (n = 75 in 1997; n = 120 in 1998) were randomly assigned by estimated calving date and body condition score to one of three treatments: 1) Control, control; 2) Inorganic, inorganic Cu supplement (200 mg Cu from CuSO4); 3) Organic, organic Cu supplement (100 mg Cu from AvailaCu). In 1998, a fourth treatment was added; 4) CU-ZN, organic Cu and Zn (400 mg Zn from AvailaZn in the Organic diet). Cows were fed a hay-based diet and individually fed supplements for approximately 45 d before and 60 d after calving (approximately January 15 to May 15 each year). Liver biopsies were obtained from cows before supplementation began, and from cows and calves at 10 and 30 d after calving. Blood samples were obtained from both cows and calves at calving, and colostrum samples were collected for IgG and mineral content. Cow liver Cu concentrations before supplementation began were 58 mg/kg in 1997 and 40 mg/kg (DM basis) in 1998. By 10 d after calving, liver Cu concentrations of Control cows had decreased (P < 0.05) to 24 mg/kg (Cu deficient) in both years, whereas liver Cu concentrations of Cu-supplemented cows increased (P < 0.05) in both years. Calf liver Cu concentrations at 10 d of age were similar (P > 0.10) for all treatment groups. No differences (P > 0.10) were found in colostrum Cu concentrations, or in calf health among treatments. No differences (P > 0.10) were found in cow BW change, calf serum Cu concentrations, calf weaning weights, or in cow 60-d pregnancy rates among treatments in either year. In 1998, cows in the Organic group had higher (P < 0.05) 30-d pregnancy rate than Control cows. Neither serum samples nor placental tissue were reliable indicators of Cu status in cows. Feeding supplemental Cu (either inorganic, organic, or organic with extra Zn) to cows with liver Cu concentrations of approximately 50 mg/kg before calving did not improve cow 60-d pregnancy rates or the health and performance of their calves when compared with unsupplemented cows.  相似文献   

17.

The effect of cadmium (Cd) and vitamin D 3 on Cd retention in the organism of laying hens was observed. Hens ( n =48) were divided into eight groups with six animals per group as follows: experimental groups 1, 3 and 5 were administered Cd (0.3, 0.6 and 6.0 mg CdCl 2 kg -1 body weight, respectively) daily in water and groups 2, 4 and 6 were administered the same CdCl 2 concentrations supplemented with vitamin D 3 (100 IU hen -1 ). C1 was a control group without any supplements and C2 a control group supplemented only with vitamin D 3 . Samples of inner organs were analysed by atomic absorption spectrophotometry after 6 months of Cd exposure. A significant elevation in Cd levels, mainly in the liver and kidneys, was found. A significant decrease ( P h 0.01) in Cd levels in the liver was recorded after the addition of 6.0 mg CdCl 2 kg -1 body weight and vitamin D 3 , in comparison with the group without vitamin D 3 (18.76 vs. 10.33 mg kg -1 ). A similar decrease in Cd levels in the kidney ( P h 0.001) at the same supplementation dose of Cd was obtained in comparison with the group without vitamin D 3 (145.32 vs. 60.37 mg kg -1 ). The results confirmed that vitamin D 3 is able to reduce the Cd content in the organism of laying hens. The main effect of vitamin D 3 was demonstrated by decreasing Cd retention in the liver and especially in the kidneys.  相似文献   

18.
本试验按照在日粮中分别添加45ppm Cd、45ppm Cd 5ppm Se、45ppm Cd 10ppmSe、45ppm Cd 15ppm Se和仅饲喂基础日粮的处理方法,将成年蛋鸡100只分成5组,对各组鸡在试验40、60、90、120d不同时期肝、肾、心、肌肉组织硒、镉的含量进行了检测.结果表明,硒可降低镉在组织器官的蓄积,且在本试验条件下,随着日被硒水平的增加,其降低效果超明显;硒对镉损害的保护效应,主要取决于日粮中适宜的Sc/Cd摩尔比值,其最适Se/Cd摩尔比约为1:3.  相似文献   

19.
Our objectives were to examine the effects of added fat in late-gestation cow diets on neonatal response to cold. In Exp. 1, pregnant fall-calving heifers received control (n = 5), safflower seed (n = 5), or whole cottonseed (n = 5) diets. The hay-based, isonitrogenous, and isocaloric diets, fed for 47 d prepartum, contained 1.5, 4.0, and 5.0% fat for control, safflower, and whole cottonseed diets, respectively. At calving, calf BW and vigor score, as well as fat, lactose, and IgG in colostrum were not affected (P > 0.30) by diet. Heifers fed the safflower diet tended to have greater colostral solids (P < 0.10) than heifers fed the control or whole cottonseed diets. At 6.5 h of age, calves were placed in a 5 degrees C cold room for 90 min. Calf vigor, shivering, body temperature, and blood samples were taken every 15 min. During cold stress, calf body temperature decreased 0.7 degrees C (P < 0.03). Across all diets, shivering and serum glucose concentrations increased (P < 0.05), whereas calf vigor and cortisol concentrations decreased (P < 0.02) during cold exposure. In Exp. 2, pregnant spring-calving cows (n = 98) received a control (n = 47) or whole cottonseed (n = 51) supplement. Hay-based diets fed for 68 d prepartum contained 2.0 and 5.0% fat for control and whole cottonseed diets, respectively. Calf BW, vigor, shivering, dystocia score, time to stand, time to nurse, serum glucose concentrations, and serum IgG were not affected (P > 0.50) by diet. Between 30 and 180 min, body temperature of calves from dams fed the whole cottonseed supplement decreased (P < 0.05) more than calves from dams fed the control supplement. Serum glucose concentrations in calves were not affected by diet (P > 0.30). Serum cortisol concentrations tended (P < 0.09) to be greater for calves from dams fed whole cottonseed than control calves. When ambient temperature was < 6 degrees C, calves born to dams fed whole cottonseed had greater (P < 0.05) BW, tended (P < 0.1) to stand earlier, and had greater serum IgG concentrations. We conclude that calves from dams fed high-fat diets containing safflower or whole cottonseed respond similarly to cold stress, but these responses may not be consistent with greater cold resistance. In addition, high-fat dietary supplementation of late-gestation cows may only be beneficial during calving seasons with prolonged cold weather.  相似文献   

20.
Heifer and steer progeny of 2-yr-old first-cross (F1) heifers and 3- to 6-yr-old F1 cows, from Hereford dams and five sire breeds, were evaluated for postweaning feedlot growth and carcass composition. Breeds of sire of dam were Angus (A), Red Poll (RP), Tarentaise (T), Simmental (Sm), and Pinzgauer (P). Calves from 2-yr-old heifers were sired by Shorthorn, and calves from 3- to 6-yr-old dams were sired by Charolais. Breed of sire of dam was significant (P less than .05 to P less than .01) for total gain and final weight for female progeny from 2-yr-old dams. At all weights, Sm, P, and T ranked above A and RP. Progeny of A, P, Sm, and T F1 2-yr-old dams were not significantly different but were higher (P less than .05) than RP heifers in total feedlot gain. Breed of sire of dam was significant (P less than .05) for carcass weight and longissimus muscle area; T ranked highest and RP lowest. Breed was not significant for any growth traits of steer progeny of 2-yr-old dams. Breed was significant for marbling score; A ranked highest and exceeded (P less than .01) both RP and Sm steers. Breed was significant (P less than .05) for most growth traits in the heifer progeny of the 3- to 6-yr-old dams bred to Charolais sires. Heifer calves of the Sm group were heavier (P less than .05) than all other groups for most weights and total gain. For total gain, P and T were intermediate and A and RP lowest. For heifer carcass traits from 3- to 6-yr-old dams, breed was significant (P less than .05 to P less than .01) for carcass weight, longissimus muscle area, percentage of cutability, and estimated kidney, heart, and pelvic fat. Heifers from Sm-sired dams were heavier (P less than .05) than those from all other groups but ranked second to heifers from P for percentage of cutability. Marbling scores of RP heifer carcasses ranked highest of all groups. Breed was not significant (P greater than .05) for any of the weights or gains in steer progeny of 3- to 6-yr-old dams; however, the Sm and P groups ranked above A and RP for all feedlot test weights.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号