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1.
The effects of an administration of the Zindep inj. preparation (Biotika) were evaluated in pregnant dairy cows as exerted on specific weight, total protein (TP) content, total immunoglobulin (IgC) and albumin (ALB) contents in colostrum. These parameters were also followed: calf's health, live weight, leucocyte (Lc) counts, T-lymphocyte (T-Ly) counts, contents of TPs, IgCs and ALBs in the blood serum of calves. Zinc concentrations were determined in colostrum, milk and calf blood serum. Our observations included 16 dairy cows in the seventh month of pregnancy in the second lactation and their calves in the winter feeding season. Eight experimental dairy cows were treated with the Zindep preparation in form of an injection to the neck muscles at a dose of 3 mg Zn/kg live weight in the mid-seventh month of pregnancy. Blood samples were taken from v. jugularis from all calves before their first drinking, on days 5, 15 and 30 of age. Colostrum, and/or milk samples were obtained by drawing of the colostrum or milk from the udder quarters within 60 minutes after parturition, on days 5 and 15 of lactation. Zn levels at birth were 16.48 +/- 2.67 mumol/l in experimental calves and 13.84 +/- 3.19 mumol/l in control calves. Zincaemia decreased slightly in both groups on days 5 and 15 of age, but it was insignificantly higher in calves coming from Zindep-treated dairy cows. Zn levels in the blood serum on the 30th day of age were 18.45 +/- 2.44 mumol/l in experimental animals and 15.73 +/- 3.11 mumol/l in control animals. Zn content in the colostrum of experimental cows was 2.40 +/- 0.42 mg/l and in the control it was 1088 +/- 0.52 mg/l (P < 0.05). On day 5 of lactation, Zn amounts in the milk of experimental dairy cows decreased to 0.95 +/- 0.12 mg/l and to 0.76 +/- 0.10 mg/l in the control (P < 0.01). Zn levels in the milk of experimental cows on day 15 of lactation were 0.95 +/- 0.13 mg/l and in the milk of control group they were 0.82 +/- 0.14 mg/l. Colostrum specific weight from zinc-treated cows was 1,067.86 +/- 0.75 g/cm3 and 1,056.8 +/- 13.53 g/cm3 in the control. TP and IgC concentrations were 137.81 +/- 38.11 g/l and 110.13 +/- 29.91 U ZST, respectively, in the colostrum of experimental group, and 105.98 +/- 32.02 g/l and 85.53 +/- 25.42 U ZST, resp., in control animals.(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

2.
In a herd of German Improved Fawn breed of goat in the year 2000 neonatal kid losses due to congenital copper deficiencies were observed. To clarify the problems and to prevent losses in the next breeding season serum copper levels of 10 dams and four control Boer goats were investigated at four time points during one year. Additionally ten kids of the following year were sampled and the serum copper levels were studied. Immediatly after parturition and 8 weeks later the dams showed low serum copper levels (10.4 +/- 11.1 micromol/l, 5.7 +/- 2.9 micromol/l resp.). At the end of the pasture season an increase of serum copper could be measured (19.3 +/- 16.0 micromol/l). To prevent enzootic ataxia due to congenital copper deficiency, the dams were treated with copper oxide wire particles in the next late gestation. At this time point serum copper concentrations started to decrease (18.5 +/- 8.4 micromol/l). The re-examination 3 month later demonstrated an increase of the serum mean copper concentrations up to 23.4 micromol/l in the dams and to 16.2 micromol/l in the kids. The serum copper levels were significantly higher compared to the levels the year before. Big variation of the serum copper levels in the control Boer goats occurred during the year, but no clinical symptoms of copper deficiency could be observed. The copper levels in the grass and soil samples were 6.8 mg/kg and 0.2 mg/kg dry substance, respectively. A secondary copper deficiency based on cadmium could be excluded through the low levels of soil samples. The contents of sulphur and molybdenum were not determined. The results indicate that the German Improved Fawn breed of goats suffered from a primary copper deficiency due to the inefficient mineral supplementation. The administration of Copinox in the last third of the gestation leads to a continious raising of the copper concentrations in the serum and is suited to prevent ataxia due to congential copper deficiency in neonatal kids.  相似文献   

3.
Serum cholic acid (SCA) and serum chenodeoxycholic acid (SCDCA) concentrations were determined in healthy dairy cows by radioimmunoassay (RIA). The levels of these two primary bile acids were correlated with the cows' reproductive status. The lowest concentrations were measured in dry cows (SCA: 7.8 +/- 3.3 mumol/l, SCDCA.: 1.5 +/- 1.0 mumol/l). In freshly calved cows SCA and SCDCA was 17.8 +/- 6.9 mumol/l and 2.3 +/- 1.0 mumol/l, respectively, while in milking cows SCA and SCDCA was 15.8 +/- 5.7 and 2.3 +/- 0.8 mumol/l, respectively. SCA concentration showed a characteristic change on the days immediately after calving: on calving day it was close to the mean SCA concentration found for dry cows, then it underwent a striking abrupt rise and reached the value typical of post-parturient cows by post-partum (PP) day 4-5. Cholic acid was found to be the major primary bile acid in the blood of dairy cows. In dry cows the SCA:SCDCA ratio is 5:1. If the serum bile acid concentration rises, the SCA:SCDCA ratio will increase further.  相似文献   

4.
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   

5.
Selenium and vitamin E concentrations were measured in the blood sera of 287 cows in 91 herds. Herds with chronic mastitis and muscle diseases had significantly lower selenium concentrations (10.4 +/- 5.26 and 11.7 +/- 8.63 micrograms/litre serum, respectively) than healthy control herds (17.7 +/- 15.00 micrograms/litre). The selenium concentrations in herds with low fertility did not differ from control herds. The vitamin E concentrations were similar in all the herds. Supplementation of the mineral mixture with 20 mg sodium selenite and 2 g vitamin E/kg on 15 farms with a deficient selenium supply increased the selenium concentrations in the blood within two months in 12 of the herds. The vitamin E concentrations were hardly influenced by the supplementation.  相似文献   

6.
The present investigation was undertaken to study the effects of surgical stress on thiobarbituric acid reactive substances (TBARS) and ferric reducing ability of plasma (FRAP) in dairy cows. Ten Holstein-Friesian dairy cows, mean age 5.26 years, admitted for treatment of left abomasal displacement (omentopexy), were used in our study. Blood samples were collected from the jugular vein prior to surgery, immediately and then 15, 30, 60, 90 min, and 2, 5, 10, and 24 h after reposition of abomasum. Surgical stress resulted in a significant increase in plasma cortisol concentrations (P < 0.001) with the highest mean levels 15 min after surgery (32.4 +/- 18.1 microg/l) as well as in serum levels of glucose (P < 0.001) and non-esterified fatty acids (P < 0.001). Similarly, surgery transiently enhanced the plasma levels of TBARS (P < 0.001). The highest TBARS plasma levels (0.91 +/- 0.18 micromol/l) were recognized 60 min after reposition of abomasums. There were no significant differences in FRAP in dairy cows before and after reposition of abomasum. In conclusion, these data indicate that stress reaction caused by surgical correction of left displacement of abomasum can be associated with higher production of TBARS.  相似文献   

7.
Serum selenium (Se), vitamin E, and resting thyroid hormone concentrations were measured in 201 horses in Prince Edward Island (PEI). Selenium concentrations were either marginal (0.0053 to 0.1200 ppm) or deficient (< 0.0053 ppm) in 79% of horses based on current reference ranges for Se in serum. Aged and young adult pleasure horses had a higher prevalence of inadequate Se concentrations compared to racehorses and broodmares (82% and 97% versus 45% and 72%, respectively). Overall, 13% of horses had inadequate (< 200 μg/dL) serum vitamin E concentrations; most of these were young pleasure horses. No horses were hypothyroid and, contrary to findings in other species, there was a positive relationship between serum thyroxine and Se concentrations (P < 0.05). We conclude that Se deficiency is widespread in PEI horse populations, especially in pleasure horses, and vitamin E deficiency is more common in young pleasure horses. Micronutrient supplementation practices employed by PEI horse owners appear inadequate to ensure sufficiency.  相似文献   

8.
The selenium content in milk of dairy cows from different countries varies between 2 and 60 micrograms/kg, because of differences in the selenium content in the feeds. With an increasing selenium content in the feed a decreasing part is secreted into the milk. A bigger part is utilized from natural selenium compounds in the feed than from selenite. In own investigations milk from Swedish cows had significantly lower selenium content during summer and autumn than during winter and spring (p less than 0,0001). The LS-means between different regions also differed significantly (p less than 0,0001). From the autumn of 1980 the feed manufacturers have been allowed to add sodium-selenite to concentrates and mineral feeds in amounts permitting a selenium content of 0,1 mg/kg DM in the total ration of dairy cows. The year after the selenium fortification was allowed, the LS-means for the selenium content of milk were 1 microgram/kg higher than the year before (p less than 0,001). In the southern parts of Sweden the selenium content was 8-10 and in the central and northern parts 7-9 micrograms/kg. These means were substantially lower than the figure of 15 micrograms/kg which was reported from the central part of Sweden two decades ago. The low selenium content in the milk during summer in some parts of Sweden could possibly mean that there is still a risk of selenium deficiency among the cattle. Anyhow the milk will not always cover the selenium requirement of the sucking or milkfed calf.  相似文献   

9.
In three separate trial series (TS) the effect of diet composition on selenium (Se) status of dairy cows were investigated. Diets were formulated based mainly on grass (TS1), grass silage (TS2) or maize silage (TS3) with different levels of Se supplementation. Each TS comprised a total of 30 dairy cows and contained one treatment group without Se supplementation (control) and two groups with increasing levels of Se supplementation (levels 1 and 2). Selenium was administered as Na-selenite. The control groups of the different TS showed a very low Se supply of 38–54 μg Se/kg DM. At level 1 the Se supply was increased to 102–165 μg Se/kg DM and at level 2 was 294–373 μg Se/kg DM. After completion of the 6-week trials the average plasma Se concentration of the control cows (without Se supplementation) across all TS was 21.5 μg/l; this increased significantly following Se supplementation, to 37.7 μg/l at level 1 and 61.5 μg/l at level 2. The plasma glutathione peroxidase (GSH-Px) activity of the control cows averaged 67 U/l, rising considerably after supplementation at level 1 to a value of 101 U/l, but showed little further increase at level 2 with a mean value of 120 U/l. By contrast, the average Se content of the milk was unchanged in the control and level 1 groups at 10.5 μg/kg and 10.9 μg/kg, respectively, and only increased markedly after supplementation at level 2 to a mean value of 15.1 μg/kg. The diet based on maize silage, while having a similar Se content as the grass and grass silage-based diets, resulted in a slightly improved Se status, which is due to a higher Se intake from soybean meal.  相似文献   

10.
The aim of the present experiment was to investigate the level of the lipid peroxidation and plasma antioxidative capacity in plasma of dairy cows at different lactation stages. Twenty six healthy dairy cows were used in our experiment. The groups: I - dry cows (n = 7), II - dairy cows < 1 month after calving (n = 9), III - dairy cows 4 - 5 months after calving (n = 10). The highest level of lipid peroxidation (TBARS) was recognized in dairy cows in early lactation (II - 0.58+/-0.42 micromol/l) with significant differences between the groups (p < 0.05). In contrast, there was a tendency (p > 0.05) to the lowest plasma antioxidative activity in cows in the same group (158 +/- 44 micromol/l). The strongest trend to metabolic imbalance was found in the dairy cows in early lactation (group II). In conclusion, the metabolic stress of dairy cows associated with early lactation resulted in an increased level of plasma lipid peroxidation.  相似文献   

11.
The copper status of dairy herds in the Waikato, Taranaki and Northland regions between 1 August and 30 September was assessed by copper determinations made on composite sera from ten cows in each herd. Comparisons were made between two major groups categorised as as received and supplemented. In the latter, the cows received 2.0-6.0 g/day of copper sulphate orally from late gestation to the end of lactation. Mean copper values were determined from pastures in Taranaki and Northland and from pastures from three soil types in the Waikato. The lowest were in Northland (134.3 micromol/kg) and the highest in Taranaki (173.3 micromol/kg). Calculated dietary available copper levels showed the lowest were from pastures grown on organic soils in the Waikato. These soils also had high molybdenum levels. Serum copper values as received were lowest in Northland (7.30 micromol/l), and were marginal for both Taranaki (9.91 micromol/l) and the Waikato (9.93 micromol/l). The levels in supplemented herds were considerably higher, i.e. from the Waikato 11.7 micromol/l and from Taranaki 11.5 micromol/l. When liver and serum copper levels from paired samples were compared there was a reasonable correlation (r = 0.64) but the standard deviation approximated the mean liver copper level, i.e. 155 +/- 141 micromol/l.  相似文献   

12.
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   

13.
The effects of zinc administration at a rate of 3 mg/kg lw. in the preparation Zindep inj. ad usum vet. (Biotika, Slovenská L'upca) were evaluated as exerted on zinc concentrations in the blood serum of 16 dairy cows in the middle of the 7th month of pregnancy. With respect to zinc injection, T-rosetted lymphocytes and beta-lysine activity were inestigated. Blood was collected from all dairy cows from v. jugularis before the preparation was administered, on days 2, 5, 8, 15, 30 and 60 after Zindep administration. Atom absorption spectrophotometry, applying a flame technique on a Perkin Elmer 1100 apparatus (Bíres, 1986), was used to determine Zn concentrations in the blood serum of all dairy cows. T-lymphocytes were determined by a rosette test after Paul et al. (1977), and beta-lysine was detected spectrophotometrically after Bucharin et al. (1987). Zinc dynamics in the blood serum of dairy cows is presented in Fig. 1. The starting values of zinc in the test cows were 9.68 +/- 2.30 mumol/l and in the control ones 10.15 +/- 1.27 mumol/l. Zincaemia of experimental dairy cows was significantly lower (P less than 0.01) on day 2 after Zindep administration, in comparison with the control group. A significant increase in zinc concentrations in the blood serum of experimental animals, in comparison with the control ones, was observed from day 8 to day 60 (P less than 0.01). The maximum zincaemia values were recorded in experimental dairy cows within days 15 and 30 (15.65 +/- 3.33, and/or 14.55 +/- 2.10 mumol/l).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

14.
Plasma alpha-tocopherol (vit E) and blood selenium (Se) concentrations in February were determined in samples from 314 dairy cows in Norway, selected to provide a representative subset of the Norwegian dairy cow population. Each sample was followed by a questionnaire with information about feeding of the cow at the time of sampling. The results were correlated to herd data and to calving and health data for each cow from the Norwegian Dairy Herd Recording System and the Norwegian Cattle Health Recording System. The mean concentrations were 6.9 microg vit E per ml plasma and 0.16 microg Se per g blood. Both levels were highest in mid lactation. Plasma vit E varied with the amount of silage fed to the cow, while blood Se varied with the amount of concentrates and mineral supplements, and with geographical region. No differences in vit E or Se levels were found between cows with recorded treatments for mastitis, parturient paresis or reproductive disorders in the lactation during or immediately prior to sampling, and those without such treatments. For ketosis, a small difference in blood Se was found between the groups with or without recorded treatments. It is concluded that winter-fed lactating cows in Norway had an adequate plasma level of vit E and a marginal-to-adequate level of Se.  相似文献   

15.
In cows from 15 dairy herds (n = 210), serum selenium (Se) concentrations ranged from 0.021 to 0.789 microgram/ml, whereas 0.05 to 0.40 microgram/ml is the reported range for adequate serum Se concentrations in cattle. Serum Se concentrations of dairy cattle appeared to follow a geographic distribution pattern. On the basis of herd mean serum Se concentrations, adequate serum Se concentrations were found in cattle from only 1 of 5 herds grazing forage in the geographic area classified as Se deficient for cattle. Adequate mean serum Se concentrations were found in cattle from 4 of 5 herds located in geographic areas described as having variable forage Se concentrations (Se-marginal areas). Of the 10 herds from these 2 areas, there were only 2 herds in which 95% of the cattle had serum Se concentrations in the Se-adequate range (0.05 to 0.40 microgram/ml). In 2 selected neighboring farms in the Se-deficient area, cattle in 1 herd had adequate serum Se concentrations and cattle in the other herd had less than adequate serum Se concentrations (less than 0.05 microgram/ml). Therefore, more cattle are at risk of developing Se-deficiency disease than is commonly believed and forage of neighboring farms may have different Se concentrations. Serum Se concentrations (up to 0.789 microgram/ml) correlated with glutathione peroxidase enzyme activity; this serum Se concentration (0.789 microgram/ml) is approximately 6.2 times higher than previously reported in dairy cattle. Therefore, RBC glutathione peroxidase activity may be useful in determining the diagnosis of chronic Se toxicosis.  相似文献   

16.
The first deer farms were established in New Zealand about 30 years ago. Extensive studies on trace elements in sheep and cattle have resulted in clarification of the requirements of those species and the development of protocols to diagnose and prevent deficiencies. In contrast, there have been very few studies conducted with deer. This review summarises information available on trace element nutrition of deer and concludes that, in New Zealand, cobalt (Co), vitamin B12, selenium (Se) and iodine (I) deficiencies are of lesser importance than copper (Cu), which can have a significant impact on deer health and performance. However, on individual farms, Se and I deficiency may cause significant production losses if not managed appropriately. There are no reports of production limitations caused by Co deficiency. Copper deficiency manifests itself as clinical disease, namely enzootic ataxia and osteochondrosis. Growth responses to Cu supplementation have only been reported in 2/11 trials and were not predicted from low serum and/or liver Cu concentrations. On the basis of clinical signs of Cu deficiency, the proposed reference ranges used to predict Cu status from serum Cu concentrations (micromol/l) are: 5, deficient; 5-8, marginal and; 8, adequate; and for liver Cu concentrations (micromol/kg fresh tissue) are: 60, deficient; 60-100, marginal and; 100, adequate. Copper supplementation strategies based on Cu-EDTA injections, Cu-oxide needles or the application of Cu to pasture are effective at increasing Cu status for varying periods. More recent research suggests that alternative forage species that have a high Cu content (10 mg/kg dry matter (DM), may play a role in the prevention of Cu deficiency.  相似文献   

17.
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   

18.
This paper describes 3 experiments comparing the effect of 10, 25 and 40 mg Se/kg, as sodium selenite, in mineral mixtures and salt licks fed to sheep. The supplement was given during the indoor season from October to May to 7 different flocks, each consisting of 50 to 100 sheep, in areas with selenium deficiency problems. The average selenium level in the basic diets did not exceed 0.05 mg/kg. Selenium status was monitored in the blood of ewes and lambs, and in milk. Blood selenium in lambs correlated well with blood selenium in their dams (r = 0.85). Selenium levels in milk on day 1 (colostrum) correlated well with selenium levels in dams (r = 0.92) and in offspring (r = 0.87). Statistically significant differences were found between the different flocks. In areas with extreme selenium deficiency, 10 mg Se/kg in mineral mixtures and salt licks proved insufficient. A content of 25 mg Se/kg, providing a daily intake of about 0.4 mg selenium, resulted in selenium levels in ewes’ blood, ewes’ milk and in the offspring that should prevent selenium deficiency disease without causing any toxic effects.  相似文献   

19.
Three groups of beef cow and calf pairs were studied to determine plasma vitamin E and blood selenium (Se) concentrations of calves at 1 month old. Group 1 was managed on irrigated pasture and calves received no Se/vitamin E injections at birth. Group 2 was managed on irrigated pasture, and the calves were injected with Se/vitamin E at birth. Group 3 was managed on dry foothill grasslands, and these cows were supplemented with 56.3 mg vitamin E and 3 mg Se daily, and the calves received a Se/vitamin E injection at birth. The plasma concentration of vitamin E in group 1 and 2 cows (9.5 +/- 1.24 and 8.43 +/- 1.0 microg/ml, respectively) was significantly higher than that of the group 3 cows (2.28 +/- 0.42 microg/ml; P < 0.05). The blood Se concentrations in group 3 cows (169 +/- 37 ng/ml) were significantly higher than those in group 1 and 2 cows (36.4 +/- 15.9 and 31.1 +/- 12.5 ng/ml, respectively; P < 0.05). Calf Se was highly correlated to cow Se (r = 0.965), and calf vitamin E was moderately correlated to cow vitamin E (r = 0.605). Calf vitamin E concentrations were consistently lower than cow vitamin E concentrations, and many values would be considered deficient.  相似文献   

20.
A number of antioxidants and trace minerals have important roles in immune function and may affect health in transition dairy cows. Vitamin E and beta-carotene are important cellular antioxidants. Selenium (Se) is involved in the antioxidant system via its role in the enzyme glutathione peroxidase. Inadequate dietary vitamin E or Se decreases neutrophil function during the perpariturient period. Supplementation of vitamin E and/or Se has reduced the incidence of mastitis and retained placenta, and reduced duration of clinical symptoms of mastitis in some experiments. Research has indicated that beta-carotene supplementation may enhance immunity and reduce the incidence of retained placenta and metritis in dairy cows. Marginal copper deficiency resulted in reduced neutrophil killing and decreased interferon production by mononuclear cells. Copper supplementation of a diet marginal in copper reduced the peak clinical response during experimental Escherichia coli mastitis. Limited research indicated that chromium supplementation during the transition period may increase immunity and reduce the incidence of retained placenta.  相似文献   

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