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1.
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There is also an error in the paper by Grace et al. in the February 2000 issue of the Journal (Vol 48, 53-56, 2000) entitled: “The effect of long-acting selenium formulations on blood and liver selenium concentrations and liveweights of red deer (Cervus elaphus)”. Throughout the article, the units of measure for pasture selenium concentrations are given as “mg Se/kg DM”; the correct unit of measure is “𝛍g Se/kg DM”.  相似文献   

2.
AIM: To compare liver copper, selenium and vitamin B12 concentrations in red deer of farmed and feral origin. METHODS: Liver samples were collected from red deer at a South Island deer slaughter premise and a game packing house in November 2000. The site of origin and age of each animal were recorded. A subsample of 107 livers was selected (n=5-10 per site of origin and age category) from farmed deer from central Canterbury, Nelson and Westland, and from feral deer from north, central and south Westland. Samples were analysed for copper, selenium and vitamin B12 concentrations and reported on a wet-matter basis. RESULTS: Mean liver copper concentrations for farmed and feral yearlings were 267 and 889 micromol/kg, respectively, and for farmed and feral adults were 206 and 677 micromol/kg, respectively. Liver copper concentrations were lower for farmed than for feral deer (p<0.001) and for feral adults than for feral yearlings (p=0.002). Mean liver selenium concentrations in farmed and feral yearlings were 2050 and 1539 nmol/kg, respectively, and in farmed and feral adults were 1938 and 1625 nmol/kg, respectively. Liver selenium concentrations varied significantly between regions and overall, farmed deer had higher liver selenium concentrations than feral deer (p=0.04). Mean liver vitamin B12 concentrations in farmed and feral yearlings were 456 and 742 nmol/kg, and for farmed and feral adults were 428 and 869 nmol/kg, respectively. Liver vitamin B12 concentrations were lower for farmed than for feral deer (p<0.001). CONCLUSION: Feral deer had higher liver copper and vitamin B12 concentrations and lower liver selenium concentrations than farmed deer in the regions studied.  相似文献   

3.
AIM: To determine the relationships between blood selenium (Se) concentrations or glutathione peroxidase activity (GSH-Px), and milk Se concentrations in dairy cows. METHODS: Seventy-two Friesian dairy cows were either untreated or injected with 0.5, 1.0 or 2.0 mg Se/kg liveweight as barium selenate (BaSeO4) formulations, resulting in 6 groups of animals with mean blood Se concentrations that varied from 212 to 2272 nmol/l. Milk samples were collected on Days 104 and 188, and blood samples were collected prior to treatment and on Days 41, 76, 104, 188, 244, and 292 after Se injection. RESULTS: Significant quadratic relationships between blood Se and milk Se concentrations, as well as blood GSH-Px activity and milk Se concentrations, were evident at Days 104 and 188. Using combined data, these were represented by the equations: milk Se = 27.3 + 0.073 blood Se -0.00001 (blood Se)2; R2=0.79, p<0.005, and; milk Se = 34.8 + 4.99 GSH-Px -0.068 (GSHPx)2; R2=0.79, p<0.005. CONCLUSIONS: The Se status of dairy cows can be assessed from milk Se concentrations. CLINICAL SIGNIFICANCE: Bulk-tank milk Se concentrations could be evaluated as a method to assess the Se status of dairy herds.  相似文献   

4.
AIMS: This paper reviews the principles for the establishment of biochemical reference criteria for assessing the trace element status of farmed livestock and summarises data for copper, selenium, vitamin B12 and iodine for farmed red deer. COPPER: Enzootic ataxia and osteochondrosis occur when liver copper concentrations are below 60 micromol/kg fresh tissue, and serum copper concentrations are below 3-4 micromol/l. Growth responses to copper supplementation have been equivocal when blood copper concentrations were 3-4 micromol/l, but were significant when mean blood copper concentrations were 0.9-4.0 micromol/l. No antler growth or bodyweight response to copper supplementation was observed when blood ferroxidase levels averaged 10-23 IU/l (equivalent to serum copper concentrations of 6-13 micromol/l) and liver copper concentrations averaged 98 mumol/kg fresh tissue. These data suggest that 'deficient', 'marginal' and 'adequate' ranges for serum copper concentrations should be 5, 5-8, and 8 micromol/l, respectively, and those for liver copper concentrations should be 60, 60-100, and 100 micromol/kg, respectively. SELENIUM: White muscle disease has been reported in young deer with blood and liver selenium concentrations of 84-140 nmol/l and 240-500 nmol/kg fresh tissue, respectively. No growth-rate response to selenium supplementation occurred in rising 1-year-old deer when blood selenium concentrations were less than 130 nmol/l, the range in which a growth-rate response would be expected in sheep. VITAMIN B12: Vitamin B12 concentrations in deer are frequently below 185 pmol/l without clinical or subclinical effects. No growth response was observed in young deer with vitamin B12 concentrations as low as 75-83 pmol/l. A growth response to cobalt/vitamin B12 supplementation occurs in lambs with serum vitamin B12 concentrations 336 pmol/l. CONCLUSIONS: Data that can be used to establish reference ranges for assessing trace element status in deer are limited. More robust reference values for farmed red deer need to be established through further studies relating biochemical data to health and performance.  相似文献   

5.
AIM: To examine the effect of intramuscular barium selenate on the blood selenium concentration of horses with marginal selenium status. METHODS: Eighteen mares were assigned to one of six groups. The mares in groups 1-4 received barium selenate at 0.5, 0.75, 1.0 and 1.5 mg Se/kg, respectively, injected into the right pectoral muscle mass. The mares in group 5 received sodium selenate at 0.05 mg Se/kg orally at 8-week intervals. The mares in group 6 were left untreated. Blood samples were collected at 0, 1, 2, 5, 10, 30, 60, 90, 120, 180, 240, 300 and 360 days after the initial treatment for assay of whole blood and plasma selenium. Injection site reactions were recorded on each sampling date. RESULTS: Treatment with barium selenate at each dose rate significantly increased whole blood, plasma and blood cell selenium concentrations when compared to no treatment or oral treatment with sodium selenate, and maintained group mean whole blood selenium concentrations in the adequate range (>1600 nmol/l) until the end of the experimental period of 1 year. The severity of injection site reactions increased with dose rate but was considered acceptable alt the lower dose rates used. CONCLUSION: The injection of barium selenate placed aseptically at a deep intramuscular site was efficacious in correcting the selenium status of mares grazing pasture with a selenium content of 0.01-0.07 mg/kg DM. However, some swelling and fibrosis at the injection site was apparent at all dose rates used. CLINICAL RELEVANCE: There is currently no long-acting selenium supplementation product licensed in New Zealand for use in horses. Barium selenate promises to provide a useful method for selenium supplementation for horses, with an effective duration of at least 1 year following a single injection.  相似文献   

6.
The efficacy of 100-day controlled release anthelmintic capsules containing Se for increasing and maintaining the Se status of lambs was evaluated. Capsules containing either 7.7 or 13.9 mg of Se increased the mean blood Se concentrations from 1.50 +/- 8.4 nmol/l in the unsupplemented lambs to 440 +/- 29.8 and 990 +/- 83.4 nmol/l respectively 100 days after their administration. Blood Se concentrations then declined to 250 +/- 21.5 and 380 +/- 50.1 nmol/l respectively by day 210. The addition of 13.9 mg of Se to a 100-day controlled release anthelmintic capsule is an effective method of protecting lambs from Se deficiency for at least 180 days.  相似文献   

7.
AIM: To determine the effect of increasing doses of long-acting injectable vitamin B12 plus selenium (Se) given pre-mating on the vitamin B12 and Se status of ewes and their lambs from birth to weaning. METHODS: Four groups of 24 Poll Dorset ewes each were injected 4 weeks pre-mating with different doses of a long-acting vitamin B12 + Se product, containing 3 mg vitamin B12 and 12 mg Se per ml. The treatment groups received 5 ml (15 mg vitamin B12 + 60 mg Se), 4 ml (12 mg vitamin B12 + 48 mg Se), 3 ml (9 mg vitamin B12 + 36 mg Se), or no vitamin B12 or Se (control). Twelve of the twin-bearing ewes per group were selected for the study. Efficacy of the product was evaluated from changes in the concentrations of vitamin B12 in serum and liver, and of Se in blood, liver and milk in the ewes during gestation and lactation, and in their lambs from birth to weaning. Pasture samples in paddocks grazed by the ewes and lambs were collected at about 2-monthly intervals from 200-m transects. RESULTS: The flock was Se-deficient, as the mean initial concentration of Se in the blood of ewes was 182 (SE 20.3) nmol/L. Compared with untreated controls, all doses significantly (p < 0.01) increased concentrations of Se in the blood of ewes for at least 300 days. Selenium concentrations in milk were likewise increased throughout lactation, as were those in the blood and liver of lambs. The mean concentration of vitamin B12 in the serum of ewes was initially > 1,000 pmol/L, but this decreased within 28 days to < 460 pmol/L. Treatment with the 5-ml and 4-ml doses raised serum vitamin B12 concentrations of ewes for at least 176 days (p < 0.01), while their lambs had significantly greater concentrations of vitamin B12 in serum and liver for less than 37 days after birth. Tissue concentrations and duration of elevation of both vitamin B12 and Se were proportional to the dose administered. The mean concentrations of Se and cobalt (Co) in the pastures were 32 and 74 microg/kg dry matter (DM), respectively. CONCLUSIONS: Injecting ewes from a Se-deficient flock 4 weeks prior to mating with 48 or 60 mg Se and 12 or 15 mg vitamin B12 increased and maintained the Se status of ewes for at least 300 days, and of their lambs from birth to weaning. The vitamin B12 status of ewes was increased for at least 176 days and that of their lambs for less than 37 days. Due to the proportional nature of the response to increasing dosage, the dose rate of the formulation tested can be adjusted according to the severity of Se and Co deficiency in a flock. CLINICAL SIGNIFICANCE: A single subcutaneous injection of vitamin B12 + Se administered pre-mating to Se-deficient flocks is likely to prevent Se deficiency in ewes and their lambs until weaning, as well as increase the vitamin B12 status of ewes and their lambs until 5 weeks after lambing.  相似文献   

8.
The aim of the study was to define possible differences between selenite, selenate and selenium yeast on various aspects of selenium status in growing cattle. Twenty-four Swedish Red and White dairy heifers were fed no supplementary selenium for 6 months. The basic diet contained 0.026 mg selenium/kg feed dry matter (DM). After the depletion period the animals were divided into 4 groups; group I-III received 2 mg additional selenium daily as sodium selenite, sodium selenate, and a selenium yeast product, respectively. Group IV, the control group, received no additional selenium. The total dietary selenium content for groups I-III during the supplementation period was 0.25 mg/kg DM. After the depletion period the mean concentration of selenium in blood (640 nmol/l) and plasma (299 nmol/l) and the activity of GSH-Px in erythrocytes (610 mukat/l) were marginal, but after 3 months of supplementation they were adequate in all 3 groups. The concentration of selenium in blood and plasma was significantly higher in group III than in groups I and II, but there was no significant difference between groups I and II. The activity of GSH-Px in erythrocytes did not differ between any of the supplemented groups. The animals in the control group had significantly lower concentrations of selenium in blood and plasma and lower activities of GSH-Px in erythrocytes than those in the supplemented groups. The activity of GSH-Px in platelets was also increased by the increased selenium intake. There was no difference in the concentration of triiodothyronine (T3) between any of the groups, but the concentration of thyroxine (T4) was significantly higher in the unsupplemented control group.  相似文献   

9.
The purpose of this study was to determine the selenium (Se) requirement in kittens. Thirty-six specific-pathogen-free kittens (9.8 weeks old) were utilized in a randomized complete block design to determine the Se requirement in cats with gender and weight used as blocking criteria. Kittens were fed a low Se (0.02 mg/kg Se) torula yeast-based diet for 5 weeks (pre-test) after which an amino acid-based diet (0.027 mg Se/kg diet) was fed for 8 weeks (experimental period). Six levels of Se (0, 0.05, 0.075, 0.10, 0.20 and 0.30 mg Se/kg diet) as Na2SeO3 were added to the diet and were used to construct a response curve. Response variables included Se concentrations and Se-dependent glutathione peroxidase activities (GSHpx) in plasma and red blood cells (RBC) as well as plasma total T3 (TT3) and total T4 (TT4). No significant changes in food intake, weight gain or clinical signs of Se deficiency were noted. Estimates of the kitten's Se requirement (i.e. breakpoints) were determined for RBC and plasma GSHpx (0.12 and 0.15 mg Se/kg diet, respectively), but no definitive breakpoint was determined for plasma Se. Plasma TT3 increased linearly, whereas plasma TT4 and the ratio of TT4 : TT3 decreased in a quadratic fashion to dietary Se concentration. The requirement estimate determined in this study (0.15 mg Se/kg) for kittens is in close agreement with other species. As pet foods for cats contain a high proportion of animal protein with a Se bioavailability of 30%, it is recommended that commercial diets for cats contain 0.5 mg Se/kg DM.  相似文献   

10.
Herbage selenium (Se) concentration is generally low in Norway. It is unknown whether feeding practices on Norwegian organic farms fulfil the dietary needs of Se and vitamin E for sheep and dairy cattle. Therefore we analysed Se in soil and herbage, and Se and vitamin E in animal blood in the indoor feeding season at 14 organic dairy and 14 organic sheep farms. The herbage Se concentration was low. Approximately 50 and 35% of all samples in the first and second cut, respectively, had Se concentrations below the detection limit of 0.01 mg/kg dry matter (DM). The median (10th, 90th percentile) Se concentrations were <0.01 (<0.01, 0.03) and 0.02 (<0.01, 0.06) mg/kg DM in the first and second cuts, respectively. Whole blood Se concentrations were 0.10 (0.04, 0.15) μg/g in dairy cattle and 0.14 (0.03, 0.26) μg/g in sheep. Vitamin E concentrations were 4.2 (2.7, 8.4) mg/l in dairy cattle and 1.3 (0.9, 2.4) mg/l in sheep. None of the soil or plant variables explained the variation in herbage Se concentration, although Se in soil and plant tended to be correlated. Herbage Se concentration was inadequate to meet the dietary Se requirements. Vitamin E requirement was only met in dairy herds. We recommend Se and vitamin E supplementation to ruminants on organic farms.  相似文献   

11.
AIM: To determine the effect of grazing pasture that had a low selenium (Se) concentration on serum concentrations of triiodothyronine (T3) and thyroxine (T4), and erythrocyte glutathione peroxidase (GSH-Px) activity in dairy cows. METHODS: Forty pregnant Friesian cows were grazed on pasture that contained 0.03-0.04 ppm Se on a dry matter (DM) basis. Two months before parturition, 20 cows were randomly selected and treated with 1 mg Se/kg bodyweight subcutaneously, as barium selenate (Group Se-S). The other group (Se-D) was not supplemented. Blood samples were taken before supplementation (-60 days) and 30, 60, 90, 180 and 270 days after parturition, for determination of concentrations of T3 and T4 in serum, and GSH-Px activity in erythrocytes. RESULTS: Erythrocyte GSH-Px activity in the Se-D group was <60 U/g haemoglobin (Hb) throughout the experiment. Supplementation increased (p<0.05) activities to >130 U/g Hb throughout lactation. Mean serum concentrations of T4 in Se-D and Se-S cows increased from 23.7 (SEM 0.7) and 23.4 (SEM 0.8) nmol/L, respectively, in the prepartum period to 69.6 (SEM 0.1) and 67.6 (SEM 0.2) nmol/L, respectively, at 180 days of lactation (p<0.01), and no effect of Se supplementation was evident. Serum concentrations of T3 in Se-D cows decreased (p<0.05) from 1.6 (SEM 0.1) nmol/L prepartum to 1.0 (SEM 0.2) nmol/L at the beginning of lactation, and remained lower (p<0.05) than those in the Se-S cows which did not decrease after calving and ranged from 1.9 (SEM 0.1) to 2.4 (SEM 0.2) nmol/L throughout lactation. CONCLUSIONS: Serum T3 concentrations decreased during early lactation in unsupplemented cows grazing pastures low in Se (0.03-0.04 ppm) and both serum T3 and erythrocyte GSHPx activities were consistently lower throughout lactation compared with Se-supplemented cows. Se supplementation had no effect on serum T4 concentrations.  相似文献   

12.
Three groups of 20-month-old pregnant Hereford heifers received 3 regimens of selenium (Se) supplementation. Group 1 received pelleted alfalfa hay, soybean meal, which contained Se (0.313 mg/kg), and 90 mg of Se as sodium selenite/kg of salt-mineral mix ad libitum. Group 2 received the pelleted hay and soybean meal, and group 3 received only the pelleted alfalfa hay. At time of parturition, the mean whole blood Se concentrations were: group 1 = 0.250 mg of Se/kg of blood, group 2 = 0.162 mg/kg, and group 3 = 0.052 mg/kg, whereas the respective mean blood glutathione peroxidase (GSH-Px) values were 144, 80, and 30 mU/mg of hemoglobin. In comparison, the mean whole blood Se values for the calves were 0.242, 0.175, and 0.81 mg/kg, respectively, and their blood GSH-Px values were 154, 113, and 50 mU/mg of hemoglobin, respectively. Thus, the blood Se and GSH-Px values for each group reflected dietary intake of Se. The calf blood GSH-Px values were similar to their dams for group 1, but were 41% higher in group 2 and 67% greater in group 3. The data suggested that the fetus can sequester blood Se, accumulating values greater than the dam, and that larger amounts were concentrated in the fetus when smaller amounts were available from the dam. The colostrum contained modest to low amounts of Se proportionate to dietary intake of this element. However, milk 7 days after parturient contained inadequate amounts of Se to sustain blood Se values in calves and the milk from heifers with low normal blood Se was essentially void of Se (0.009 mg/kg). (ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

13.
This study was conducted to determine the effect of Se supplementation and source on the Se status of horses. Eighteen 18-mo-old nonexercised horses were randomly assigned within sex to 1 of 3 treatments: 1) control (CTRL, no supplemental Se, 0.15 mg of Se/kg of total diet DM); 2) inorganic Se (INORG, CTRL + 0.45 mg of Se/kg of total diet DM from NaSeO3); or organic Se [ORG, CTRL + 0.45 mg of Se/kg of total diet DM from zinc-L-selenomethionine (Availa Se, Zinpro, Corp., Eden Prairie, MN)]. Horses were acclimated to the CTRL diet (7.1 kg of DM alfalfa hay and 1.2 kg of DM concentrate per horse daily) for 28 d. After the acclimation period, the appropriate treatment was top-dressed on the individually fed concentrate for 56 d. Jugular venous blood samples were collected on d 0, 28, and 56. Middle gluteal muscle biopsies were collected on d 0 and 56. Muscle and plasma were analyzed for Se concentrations. Glutathione peroxidase activity was measured in muscle (M GPx-1), plasma (P GPx-3), and red blood cells (RBC GPx-1). Data were analyzed as a repeated measures design. Mean plasma Se concentration on d 28 and 56 was greater (P < 0.05) for Se-supplemented horses compared with CTRL horses, and tended (P < 0.1) to be greater in ORG vs. INORG on d 28. Mean muscle Se concentration and P GPx-3 activities increased (P < 0.05) from d 0 to 56 but were not affected by treatment. Mean RBC GPx-1 activity tended to be greater (P < 0.1) in ORG than INORG or CTRL horses on d 28, and tended to be greater (P < 0.1) for INORG compared with ORG horses on d 56. Mean RBC GPx-1 activity of INORG and ORG horses was not different from that of CTRL on d 56. Mean M GPx-1 activity decreased (P < 0.01) from d 0 to 56. In conclusion, zinc-L-selenomethionine was more effective than NaSeO3 at increasing plasma Se concentration from d 0 to 28; however, both supplemental Se sources had a similar effect by d 56. No difference in Se status due to Se supplementation or source could be detected over a 56-d supplementation period by monitoring middle gluteal muscle Se, M GPx-1, or P GPx-3. Results for RBC GPx-1 also were inconclusive relative to the effect of Se supplementation and source.  相似文献   

14.
Long-acting selenium treatments for sheep   总被引：1，自引：0，他引：1  
An intraruminal selenium (Se) pellet and a subcutaneous depot of barium selenate, equivalent to 1.6 mg Se/kg body weight, were each effective in maintaining increased blood Se concentrations for at least 200 weeks in ewes at pasture. These treatments given to the ewes 23 to 26 weeks before lambing increased the Se status of their lambs for 4 to 6 months.  相似文献   

15.
The aim of this trial was to determine whether the selenium status of suckling calves could be improved by supplementing their dams' diet with organic Se instead of sodium selenite. A herd of 103 Hereford cows, which were on grass paddocks all year round, was divided into two groups. Both groups had free access to a mineral supplement that contained 30 mg of Se/kg; for one group the source of the Se was a Se yeast product, and for the other group the source was sodium selenite. The basal feed contained .02 mg of Se/kg DM. During the trial, the mean daily consumption of the mineral supplement was approximately 110 g/cow. The calving season started in the middle of March and ended in the middle of May. Blood samples were taken from 11 cows and their calves in the yeast group and from nine in the selenite group at the end of April and again at the beginning of June, and milk samples were taken at the same times. At both samplings, the concentration of Se in whole blood and the activity of glutathione peroxidase (GSH-Px) in the erythrocytes of the cows and calves in the yeast group were higher than in the samples from the animals in the selenite group. The same pattern was seen for plasma, except for the cows at the first sampling. The mean concentrations of Se in whole blood from calves in the yeast and selenite groups were 130 and 84 microg/L, respectively, and plasma concentrations were 48 and 34 microg/ L, respectively. Mean Se concentration in the milk from the yeast group (17.3 microg/L) was higher than that in milk from the selenite group (12.7 microg/L). There were significant correlations (r = .59 to .68) between the concentrations of Se in the cow's milk or cow's whole blood compared with Se concentrations in the calves whole blood and plasma or with the erythrocyte GSH-Px activity of the calves. The Se status of the calves in the selenite group was considered to be marginal, but the status of the calves in the yeast group was considered to be adequate. Supplementation of the suckler cows' diet with organic Se in the form of Se yeast rather than sodium selenite improved the Se status of their calves when the Se was mixed into a mineral supplement containing 30 mg of Se/kg. In practice, such supplementation would probably eliminate the risk of nutritional muscular degeneration in suckling calves.  相似文献   

16.
An experiment was conducted to estimate the relative bioavailability of inorganic Se sources based on tissue Se deposition following supplementation at high dietary levels. Twenty-eight crossbred wethers averaging 50 kg initial weight were assigned randomly to seven treatments that were fed for 10 d. The basal diet contained .18 mg/kg Se (DM basis). Dietary Se was added at 0, 3, 6 or 9 mg/kg as reagent grade sodium selenite (Na2SeO3) and 6 mg/kg from either calcium selenite (CaSeO3), Na2SeO3 + fumed amorphous carrier or sodium selenate (Na2SeO4). There were four sheep per treatment group, housed in individual, raised pens with slatted floors. Daily feed intake was restricted to 1,200 g and tap water was available ad libitum. The basal diet was fed for a 10-d adjustment period, then sheep were fed experimental diets for 10 d. At the termination of the experiment, blood samples were taken; sheep were stunned and killed, and livers and kidneys were removed and frozen for Se analysis. There was a linear (P less than .001) uptake of Se in liver, kidney and serum. The CaSeO3 and Na2SeO4 sources resulted in greater (P less than .05) Se concentrations in liver and kidney than did Na2SeO3, but these differences were not significant when the analyzed dietary Se concentrations were used as a covariate in the statistical model. Based on linear and multiple linear regression slopes and average increases in serum, liver and kidney Se concentrations, estimated relative bioavailability values corrected for analyzed dietary concentration, were 100, 101, 90 and 133 for Na2SeO3, CaSeO3, Na2SeO3 + carrier and Na2SeO4, respectively.  相似文献   

17.
Six nine-month-old red deer were injected intramuscularly with a long-acting injectable solution of oxytetracycline (Terramycin-LA, Pfizer Ltd) at a dose rate of 20 mg/kg. Four similar control deer were injected with saline. There was no significant pain response to injection, and only minor palpable swellings at the injection site were observed in three oxytetracycline-treated and one control animal. No statistically significant changes in white blood cell numbers, blood fibrinogen, creatine phosphokinase or glutamic oxaloacetic transaminase concentrations occurred as a result of oxytetracycline administration up to seven days after injection. Mean plasma oxytetracycline concentration reached a peak (4.68 mg/l) two hours after injection and declined to levels below assay sensitivity (0.3 mg/l) in five deer 72 hours after injection, and in all deer by 96 hours after injection. No gross lesions at the injection site were observed at slaughter 30 days after injection. There were traces of oxytetracycline at the injection site muscle of two deer after 30 days, but residues were not detected in injection site muscle from the other four deer, or in any of the liver, kidney or other muscle specimens.  相似文献   

18.
Vitamin E, selenium and polyunsaturated fatty acids (PUFAs) were determined in feed used at three piggeries over.a four week period and compared with corresponding concentrations in clinically normal grower pigs at slaughter. Mean values were vitamin E: 59 IU/kg (feed), 6 micromol/kg (liver), 1.7 micromol/l (serum); and selenium: 310 microg/kg (feed), 5200 nmol/kg (liver), 1700 nmol/l (blood). Alpha-tocopherol accounted for 80% of the mean vitamin E activity in the feed and over 95% that in the liver and serum. The mean ratio of PUFA to total fatty acid (FA) in the feed (38%) was similar to that in the serum (36%) and liver (39%), but the ratio of peroxidisable PUFA (PPUFA) to FA increased from 1.7% in the feed to 4.2% in the serum and 10.8% in the liver. The ratio of alpha-tocopherol (mmol) to PPUFA (mol) in the liver varied from 0.16 to 0.48. The relationship of these data to the VESD syndrome is discussed in the light of other published data.  相似文献   

19.
This study assessed the effects of dietary selenium (Se), iodine (I) and a combination of both on growth performance, thyroid gland activity, carcass characteristics and the concentration of iodine and selenium in Longissimus lumborum (LL) muscle in goats. Twenty‐four bucks were randomly assigned to four dietary treatments: control (CON), basal diet without supplementation, basal diet + 0.6 mg Se/kg dry matter (DM) (SS), 0.6 mg I/kg DM (IP), or combination of 0.6 mg/kg DM Se and 0.6 mg/kg DM I (SSIP) and fed for 100 days. Animals fed diet SSIP exhibited higher (P < 0.05) body weight and better feed conversion ratio (FCR) than those fed other diets. Dressing percentage of goats fed the supplemented diets was higher (P < 0.05) than that of the control. Carcasses from the IP group had higher (P < 0.05) total fat proportion than the SSIP group. The levels of both elements were significantly elevated (P < 0.05) in LL muscle in supplemented goats. Thyroid follicular epithelial cells of IP and SSIP animals were significantly higher than those of CON and SS groups. The study demonstrated that the combined Se and I dietary supplementation improves growth performance, carcass dressing percentage and increases the retention of Se and I in goat meat.  相似文献   

20.
Twenty Angus cross heifers were fed a complete diet which contained 0.07 mg selenium/kg dry matter. Thirteen were injected subcutaneously with barium selenate at a dose rate of approximately 1 mg selenium/kg bodyweight and seven remained untreated. All the heifers were slaughtered during the following 121 days, the last of the treated group 119 days after injection. Glutathione peroxidase activity in blood increased within four weeks of administration and remained high thereafter. The selenium dependent glutathione peroxidase activity did not increase in liver kidney or muscle. The concentrations of selenium in the blood, liver and muscle were increased significantly from 30 days until 119 days. Between 76 and 99 per cent of the selenium injected remained at the site of injection.  相似文献   

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