Vitamin E, selenium and polyunsaturated fatty acids in clinically normal grower (9-16 weeks old) pigs and their feed: their relationship to the vitamin E/selenium deficiency ("VESD") syndrome

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.     

Liver copper, selenium and vitamin B12 concentrations in farmed and feral red deer (Cervus elaphus)

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.     

A review of tissue reference values used to assess the trace element status of farmed red deer (Cervus elaphus)

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.     

Alpha-tocopherol, selenium and polyunsaturated fatty acid concentrations in the serum and feed of spring-calving dairy heifers

The objectives of this study were to provide baseline data for alpha-tocopherol, selenium and polyunsaturated fatty acid concentrations in the serum and feed of New Zealand dairy cattle, and to assess the likelihood that abnormal peroxide metabolism has a role in the impaired lactational and reproductive performance noted in selenium-deficient cattle. Twenty-four Friesian heifers were randomly allocated one of four winter diets consisting of hay with or without selenium supplementation, or pasture and silage with or without selenium supplementation. A winter diet consisting exclusively of hay (alpha-tocopherol concentration 19 mg/kg of dry matter) resulted in a pre-calving serum alpha-tocopherol concentration of 1.2 mg/l compared to 4.5 mg/l for pastured heifers (p<0.01). The pre-calving alpha-tocopherol concentration for the heifers fed hay fell into the range considered deficient (<2.0 mg/l), whereas heifers fed pasture and silage remained in the range considered adequate throughout the study period. Serum fatty acid concentration, and the proportion of fatty acids that were polyunsaturated, were lowest in the hay-fed heifers before calving (1.0 mg/ml, 37.1% respectively), and remained unchanged following re-introduction to pasture after calving in late July and August. Serum fatty acid concentration did not increase following the re-introduction of the heifers to pasture because of the unexpectedly low fatty acid concentration (4.8 g/kg of dry matter) of the mature winter pasture. In October, however, the proportion of fatty acids in serum that were polyunsaturated increased (50%) as did serum cy-tocopherol concentrations (greater than 13 mg/l). Mean serum selenium concentrations in the unsupplemented heifers ranged from 139 to 204 nmol/l, being lowest in October (p<0.01). Supplementation with intraruminal selenium pellets (two pellets delivering about 3 mg of selenium/day) increased serum selenium concentration and glutathione peroxidase activity (p<0.01) whereas the type of winter diet had no effect (p>0.05). These results suggest that dairy cattle wintered on hay can become Vitamin E-depleted, whereas the feeding of pasture and silage should provide adequate Vitamin E. The pasture offered following calving during July and August provided a low dietary polyunsaturated fatty acid challenge, suggesting that abnormal peroxide metabolism is unlikely to be an important mechanism in the impaired performance of selenium-deficient adult cattle which calve at this the of year.     

Vitamin E,selenium and polyunsaturated fatty acids in clinically normal grower (9–16 week old) pigs and their feed: their relationship to the vitamin E/selenium deficiency (“VESD”) syndrome

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 μmol/kg (liver), 1.7 μmol/1 (serum); and selenium: 310 μg/kg (feed), 5200 nmol/kg (liver), 1700 nmol/1 (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 α-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.     

The effect of long-acting injectable selenium formulations on blood and liver selenium concentrations and liveweights of red deer (Cervus elaphus)

AIM: To evaluate the efficacy of a new long acting injectable selenium ( Se ) formulation to increase the Se status and prevent Se deficiency in red deer. METHODS: Groups of weaned red deer (four stags and six hinds/group) grazing pastures containing <30 mg Se/kg DM were injected subcutaneously with either 0.5, 1.0 or 2.0 mg Se/kg as a new formulation of BaSeO4 (Deposel Multidose), 1.0mgSe/kg of a current formulation (Deposel), or not treated. Blood Se concentrations and liveweight were measured nine times at intervals over 377 and 270 days, respectively. RESULTS: Both formulations of Se elevated blood Se concentrations from 105 nmol/l pre-injection for at least 377 days with peak levels of 1894, 1395 and 818 nmol/l for high, medium and low doses of Deposel Multidose, respectively, at 73141 days, and 1508 nmol/l at 73-141 days for the medium dose of Deposel, which persisted at similar levels for the duration of the study. Deposel Multidose produced fewer and less severe subcutaneous tissue reactions than Deposel. Pastures contained 10 to 30 mg Se/kg DM. There was no significant difference in growth rate between treated and control deer. There was a significant (p<0. 01) linear relationship (y = 1.25x + 71.6, R2=0.86) between blood (x) and liver (y) Se concentrations in the range of 120 - 2100 nmol/l for blood concentrations, and 200 - 3000 nmol/kg for liver concentrations. CONCLUSION: Injections of BaSeO4 in both formulations studied were effective in increasing the Se status of deer but the new formulation produced fewer and less-severe tissue reactions. Young growing red deer appear less sensitive to Se deficiency as measured by weight gain, than sheep and cattle, suggesting that reference ranges for those species are not appropriate for deer. There was a linear correlation between blood and liver selenium concentrations.     

Vitamin E, selenium, and polyunsaturated fatty acid concentrations and glutathione peroxidase activity in tissues from pigs with dietetic microangiopathy (mulberry heart disease)

Tissues of 27 pigs with spontaneous dietetic microangiopathy (DM) and of 27 control pigs that died of causes unrelated to vitamin E and selenium (E-Se) deficiency were analyzed for alpha-tocopherol, Se and polyunsaturated fatty acid (PUFA) concentrations and for glutathione perioxidase (GSH-Px) activity. These variables (except for GSH-Px) also were measured in rations fed to control pigs and pigs with DM. Swine with DM had lower heart and liver alpha-tocopherol concentrations than did control pigs. Heart and kidney Se concentrations and heart and liver PUFA concentrations were similar in pigs of either group. Diets fed to both groups of pigs contained similar content of alpha-tocopherol, Se, oil, and PUFA; alpha-tocopherol and Se concentrations in the diets of both groups of pigs were high. In spite of apparently adequate amount of dietary alpha-tocopherol, results indicate that pigs with DM had lower tissue alpha-tocopherol concentration than did control pigs. Spontaneous DM is associated with altered alpha-tocopherol metabolism, but is unrelated to alterations in dietary Se and PUFA contents and tissue Se and PUFA concentrations and GSH-Px activity.     

Experimental myopathy in vitamin E- and selenium-depleted calves with and without added dietary polyunsaturated fatty acids as a model for nutritional degenerative myopathy in ruminant cattle

Fourteen calves, 14 weeks old, fed a low vitamin E and selenium diet based on sodium hydroxide-treated, selenium-deficient barley showed a rapid decline in plasma alpha-tocopherol, a gradual decline in erythrocyte glutathione peroxidase (GSHPX) activity, elevated plasma creatine kinase (CK) activity, teeth grinding and (in three cases) electrocardiographic changes, but no clinical abnormalities after 127 to 137 days. Necropsy of six depleted calves at that stage revealed pale muscles in two animals and mild histopathological lesions of skeletal myopathy in all six calves. Ten control calves were fed a similar diet supplemented with alpha-tocopherol and selenium. Plasma alpha-tocopherol and erythrocyte GSHPX activity remained high in these calves and no clinical abnormalities or evidence of myodegeneration were observed. When protected linseed oil was fed as a source of polyunsaturated fatty acids to the remaining eight depleted calves, rapid elevations in plasma CK activity and linolenic acid associated with a variety of cardiopulmonary and locomotory signs, electrocardiographic changes and myoglobinuria occurred within six to 11 days. Necropsy revealed widespread severe skeletal myodegeneration (eight calves) and myocardial lesions (five calves) with preferential involvement of the left ventricular myocardium. Clinical signs and pathological changes were similar to those reported in field outbreaks of nutritional degenerative myopathy in ruminant cattle and establish the experimental regime as the first successful model for reproduction of this disease.     

Serum beta-carotene and alpha-tocopherol in horses fed beta-carotene via grass-meal or a synthetic beadlet preparation with and without added dietary fat

The serum response of beta-carotene as an indicator of bioavailability was compared after feeding beta-carotene (0.8 mg/kg body weight) either from grass meal or a synthetic beadlet preparation (Lucarotin). Both were each given without or with added dietary vegetable fat (2-2.5% vs. 6.6% fat in dry matter) in a Latin square design with four horses. The nutritionally complete diet was supplemented with alpha-tocopherol (4 mg/kg body weight). Each treatment period (4 weeks, two serum samples) was followed by a washout period of 4 weeks with low intakes of beta-carotene (traces) and alpha-tocopherol (0.5 mg/kg body weight). Within 4 weeks of supplementation, serum beta-carotene increased about 10-fold, from a mean initial concentration of 0.05-0.53 micromol/l. There was no effect of beta-carotene source and of fat addition, respectively. Faecal excretion of beta-carotene ranged from 55 to 81% of intake. No beta-carotene was detected in any urine sample. Serum alpha-tocopherol (across all time points and animals, n=64) was 14.5 micromol/l. During supplementation, the values were significantly higher than during washout-periods. Additional dietary fat did not affect the serum response. Faecal excretion of alpha-tocopherol ranged from 69 to 121% of intake. Fat addition resulted in a significant decrease of serum cholesterol. In conclusion, the natural and the synthetic source of beta-carotene showed significant and identical bioavailability independent of additional fat.     

Use of copper oxide wire particles (Copinox) for the prevention of congenital copper deficiency in a herd of German Improved Fawn breed of goat

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.     

Trace elements in grass, cattle liver and sheep liver from districts surrounding Karatina, Kenya. I. Selenium

Samples of grass, cattle and sheep livers from the districts surrounding Karatina, Kenya, were analysed for their contents of selenium. The following mean values were found: Grass (n = 31): 0.19 +/- 0.17 mg Se/kg on dry matter basis, cattle liver (n = 96): 0.31 +/- 0.10 mg Se/ kg on wet weight, and sheep liver (n = 93): 0.55 +/- 0.25 mg Se/kg on wet weight. It is concluded that selenium deficiency is unlikely to occur in the districts included in this investigation.     

Impact of molybdenum on the copper status of red deer (Cervus elaphus)

AIM: To determine the effect of increasing molybdenum (Mo) intakes on serum and liver copper (Cu) concentrations and growth rates of grazing red deer (Cervus elaphus). METHODS: Molybdenum- and Cu-amended fertilisers were applied to six 1.1-ha paddocks in a 3 x 2 design. Three levels of Mo were applied on two paddocks at each level in mid April (designated Day 1); levels were: none (control), 0.5 (medium) and 1.0 (high) kg Mo/ha as sodium molybdate. In late May (Day 39), two levels of Cu (none and 3.0 kg Cu/ha, as copper sulphate) were applied to each of the three levels of Mo-treated paddocks. Pasture Mo, Cu and sulphur (S) concentrations were measured at about fortnightly intervals. In late June (Day 74), ten 6-month-old red deer hinds were placed on the six experimental pastures, and serum and liver Cu concentrations were monitored at about monthly intervals for 102 days. The hinds were weighed on four occasions during the trial. RESULTS: Mean pasture Mo concentrations on Day 56 were 2, 4.6 and 11.3 mg/kg dry matter (DM) for the untreated control, medium and high Mo-treated pastures, respectively. Pasture Cu concentration was 95 mg/kg DM on Day 59, 53 mg/kg DM on Day 90, and 9 mg/kg DM by Day 153. Mean S concentration in pasture was 3.3 (range 3.03-3.45) g/kg DM. Copper application to pasture had no significant effect on serum and liver Cu concentrations in deer so data were pooled within Mo treatment. Mean initial (Day 74) serum Cu concentration was 9.2 micromol/L. In the deer grazing the control Mo pasture, this increased to 10.3 micromol/L on Day 112, before decreasing to 6.4 micromol/L on Day 176. In deer grazing the medium and high Mo-treated pastures, mean serum Cu concentrations were 3.8 and 3.9 micromol/L, respectively, on Day 112, and 2.5 and 3.3 micromol/L, respectively, on Day 176. Mean initial (Day 74) liver Cu concentration was 131 micromol/kg fresh tissue. In the deer grazing the control Mo pasture, this declined to 120 and 52 micromol/kg on Days 112 and Day 176, respectively. In deer grazing the medium and high Mo-treated pastures, liver Cu concentrations decreased to 55 and 52 micromol/kg fresh tissue, respectively, on Day 112, and 21 and 20 micromol/kg fresh tissue, respectively, on Day 176. Mean serum and liver Cu concentrations were not significantly different between deer grazing the medium and high Mo-treated pastures, and were lower (serum p=0.003, liver p<0.001) in those groups than in deer grazing the untreated control pastures. No clinical signs of Cu deficiency associated with lameness were observed. Deer grazing pastures that had Mo concentrations >10 mg/kg DM had lower (p=0.002) growth rates (100 vs 130 g/day) than those on pastures containing <2.4 mg Mo/kg DM. CONCLUSION: Increasing pasture Mo concentrations from 2 mg/kg DM to > or =4.6 mg/kg DM significantly reduced serum and liver Cu concentrations in grazing deer. Reduced growth rate was observed at pasture Mo concentrations >10 mg/kg DM.     

A lupinosis-associated myopathy in sheep and the effectiveness of treatments to prevent it

A lupinosis-associated myopathy occurred in 26 of 48 sheep given a crude toxic extract of Phomopsis leptostromiformis, and in 18 of 34 sheep that grazed a toxic lupin stubble. Treatment with selenium or alpha-tocopherol alone neither prevented nor cured the myopathy, but selenium and alpha-tocopherol together may have been partially effective. Among the group of 48 intoxicated sheep, those with myopathy had a significantly lower mean terminal concentration of alpha-tocopherol in their livers than those with no myopathy. There was no relationship between the severity of liver injury and the occurrence of the myopathy. It was considered that this lupinosis-associated myopathy may have a similar pathogenesis to nutritional myopathy. Data on plasma creatine phosphokinase and erythrocyte glutathione peroxidase activities, plasma alpha-tocopherol concentrations and terminal tissue concentrations of selenium and alpha-tocopherol are presented.     

Effect of vitamin E supplementation of sheep and goats fed diets supplemented with polyunsaturated fatty acids and low in Se

Vitamin E (VitE) and selenium (Se) are an essential part of the antioxidative functions of metabolism. There are situations of low supply of both micronutrients. As VitE is involved in ruminal biohydrogenation of polyunsaturated fatty acids (PUFA) and their protection against oxidation in metabolism, diets supplemented with PUFA may challenge VitE to an extent making recommended supplies insufficient. Twelve goats and sheep each were fed a diet supplemented with PUFA and characterised by low Se and limited VitE contents during the last 2 months of gestation and the first 2 months of lactation. The basal diet consisted of hay and concentrate. Six goats and sheep received extra VitE, while the control groups received no extra VitE. Blood and milk samples were taken. In addition, liver, heart muscle and spleen samples were obtained from the offspring after slaughtering at an age of 8 weeks. No significant changes were observed in serum Se and VitE. A significant increase in serum VitE concentrations between 2 and 4 weeks postpartum (pp) was evident in the supplemented kids. In 4, 6 and 8 weeks pp, the serum concentrations of VitE in the supplemented kids were significantly higher compared to the unsupplemented group. In the kids, VitE was higher in liver of the supplemented groups. There were no significant differences in response to extra VitE between sheep and goat. The kids responded to serum VitE different from that of lambs, as a significant difference was observed between supplemented and unsupplemented animals in the goat kids, but not the lambs. In conclusion, goats and sheep have to be viewed differently and may not be considered alike relating to VitE/Se metabolism and requirements, especially in young animals.     

Prognostic indicators of post partum viability of kids born to Escherichia coli-vaccinated or unvaccinated does

This study was undertaken to determine some blood and other physiological parameters with potential for use as prognostic indicators of viability of newborn goat kids. Of the 143 kids born during the on-farm study, 97 were crosses of Galla x Small East African (SEA) and 46 were pure SEA. The SEA x Galla kids were 46 single males, with a mean body weight at birth of 2.77 +/- 0.22 kg, 43 females with a mean body weight at birth of 2.36 +/- 0.76 kg and 5 and 3 sets of female and male twins (mean body weight at birth of 1.8 +/- 0.19 kg and 2.05 +/- 0.07 kg for the female and male kids, respectively). The SEA kids comprised 36 single male and female kids (mean body weight at birth of 2.48 +/- 0.04 kg and 10 sets of twins (both male and female) (mean body weight at birth of 1.50 +/- 0.04 kg ). Pre-suckling sera obtained on-station from kids born of does vaccinated against Escherichia coli (n = 8) and unvaccinated does (n = 7) had a total protein content of <40.0 g/l and no detectable levels of IgG and A or E. coli antibodies. Sera obtained 12 hours post partum) from kids that survived in both groups contained about 19-22 g of Ig g/l, 50-80 g total protein/l, blood glucose of >5 mmol/l and had an E. coli antibody titre of between 1/160 and 1/640. On the other hand, kids that died within 48 hours of birth (parturient deaths) and had been classified in categories 3 and 4 righting reaction had low (<40 g/l) total protein, low white blood cell count (4,000/ml) and low blood glucose concentration (<4.9 mmol/l). It is concluded that kids with delayed righting reaction (>45 minutes), low rectal temperature (<36 degrees C), low birth weights (<1.5 kg for singles and <1.0 kg for twins), low white blood cells (<4,000/ml), low (<2 mmol/l) blood glucose levels, low total protein (<40.0 g/l), low (<1:160) E. coli antibody titre and IgG (< or =3,350 mg/l) in sera obtained 12 hours after birth have a poor prognosis for survival.     

Effect of vitamin E supplementation and partial substitution of poly- with mono-unsaturated fatty acids in pig diets on muscle, and microsome extract alpha-tocopherol concentration and lipid oxidation.

The experiment was organized in a 3 x 2 factorial arrangement with three dietary fat blends and a basal (20 mg kg(-1) diet) or supplemented (220 mg kg(-1)) level of alpha-tocopheryl acetate. Dietary vitamin E and monounsaturated to polyunsaturated fatty acid ratio (dietary MUFA/PUFA) affected muscle alpha-tocopherol concentration (alpha-tocopherol [log microg g(-1)] = 0.18 (+/- 0.105) + 0.0034 (+/- 0.0003) x dietary alpha-tocopherol [mg kg(-1) diet] (P < 0.0001) + 0.39 (+/- 0.122) x dietary MUFA/PUFA (P < 0.0036)). An interaction between dietary alpha-tocopherol and dietary MUFA/PUFA exists for microsome alpha-tocopherol concentration (alpha-tocopherol [log microg g(-1)] = 1.14 ( +/- 0.169) (P < 0.0001) + 0.0056 ( +/- 0.00099) x dietary alpha-tocopherol [mg kg(-1) diet] (P <0.0001) + 0.54 (+/- 0.206) x dietary MUFA/PUFA (P < 0.0131) - 0.0033 (+/- 0.0011) x dietary alpha-tocopherol [mg kg(-1))] x dietary MUFA/PUFA (P < 0.0067)), and hexanal concentration in meat (hexanal [ng x g(-1)] = 14807.9 (+/- 1489.8)- 28.8 (+/- 10.6) dietary alpha-tocopherol [mg x kg(-1)] (P < 0.01) - 8436.6 (+/- 1701.6) x dietary MUFA/PUFA (P < 0.001) + 24.0 (+/- 11.22) x dietary alpha-tocopherol-dietary MUFA/ PUFA (P < 0.0416)). It is concluded that partial substitution of dietary PUFA with MUFA lead to an increase in the concentration of alpha-tocopherol in muscle and microsome extracts. An interaction between dietary alpha-tocopherol and fatty acids exists, in which at low level of dietary vitamin E inclusion, a low MUFA/ PUFA ratio leads to a reduction in the concentration of alpha-tocopherol in microsome extracts and a concentration of hexanal in meat above the expected values.     

Serum glutathione peroxidase activity reflects short-term increases in selenium intake in goats

The objective of this study was to determine if serum glutathione peroxidase activity reflects short-term changes in the selenium status of goats. Angora goat kids (n=14) were fed pelleted luceme containing 20 microg/kg of selenium, and treated orally with either selenium (0.1 mg/kg of liveweight weekly, as sodium selenate) or de-ionised water. Serum activity of glutathione peroxidase was increased in response to supplementation and differed from that of controls within 24 hours of supplementation. The change in serum glutathione peroxidase activity during the 21 days after the start of weekly supplementation closely followed changes in serum selenium concentration. The results of this study suggest that serum glutathione peroxidase activity reflects the short-term improvement in the selenium status of Angora goat kids following oral supplementation with sodium selenate.     

Osteochondrosis, skeletal abnormalities and enzootic ataxia associated with copper deficiency in a farmed red deer (Cervus elaphus) herd

A red deer herd of 150 mixed-age hinds, 48 stags and 102 weaners was identified as severely copper deficient during an observational study of 15 deer farms in the lower North Island of New Zealand during 1992 and 1993. Severe lameness was observed in nine weaners in 1992 (8.8% prevalence) and 15 in 1993 (12% prevalence). Typical abnormalities included swollen hocks and carpal joints and outward rotation of hind legs with hocks touching. At postmortem examination, there were epiphyseal fractures of the femoral head, severe degenerative arthropathy of the coxo-femoral joints and erosions of cartilage in many other limb joints. Osteochondrosis was confirmed histologically. Concurrently, three adult hinds and one adult stag developed into-ordination typical of enzootic ataxia which was confirmed histologically. Blood and liver copper concentrations in untreated affected weaner deer ranged from undetectable to 16.0 micromol/l (mean 7.6 micromol/l) and 25 to 53 micromol/kg (mean 39 micromol/kg), respectively. Mean blood copper concentrations in unaffected weaners in March 1992 and 1993 were 5.3 micromol/l and 4.4 micromol/l, respectively. The mean blood copper concentration in seven hinds in September 1992, prior to onset of clinical signs of enzootic ataxia, was 1.5 micromol/l (range 1.0-2.4 micromol/l). At other times of the year, mean blood copper concentrations ranged up to 12.5 micromol/l in adults and 8.9 micromol/l in weaners before treatment began in 1993. Pasture analyses showed copper contents of 6-11 ppm in 11 samples collected during 1992 and 1993. Sulphur ranged from 0.18 to 0.37%, molybdenum from 0.51 to 3.56 ppm and iron from 130 to 2886 ppm. These measurements supported a diagnosis of secondary copper deficiency. Supplementation with oral oxidised copper wire particles was undertaken from December 1992, resulting in an improvement in blood copper concentrations in some classes of deer. No further clinical abnormalities have been observed.     

Selenium levels in the blood, liver, kidney and muscle of sheep after the administration of iron/selenium pellets or soluble-glass boluses

Slow-release devices composed of elemental selenium and iron or a soluble-glass containing selenium, cobalt and copper were effective in significantly raising blood and tissue selenium levels of sheep at pasture. Three out of six animals given a soluble-glass bolus lost them over the four months of the trial. In contrast, all six animals retained their iron-selenium pellets. Selenium levels in the kidney cortex four months after administration of the devices, when peak levels were most likely to occur, were approximately 12.7 micromol/kg (1mg/kg). This value is 50% of the maximum permitted level in edible tissue in New Zealand. There was no obvious pattern of distribution of selenium throughout the liver. Variations in concentration from one site to another were, in some cases, almost two-fold. Therefore the analysis of liver biopsy samples gives only an approximate assessment of the mean hepatic concentration.     

Serum T3 and T4 concentrations in lambs with nutritional myodegeneration

BACKGROUND: Selenium (Se) deficiency is an important etiological factor in Nutritional Myodegeneration Disease (NMD) of lambs, and Se is required for synthesis of thyroid hormones. HYPOTHESIS: That serum T4 and T3 concentrations in lambs with NMD will be abnormal. ANIMALS: Ten healthy lambs and 15 lambs with NMD were included in the study. METHODS: Serum thyroid hormone concentrations were measured by chemiluminescence assay in samples collected from control and NMD lambs before and after treatment with a preparation containing sodium selenite, vitamin E, and vitamin B1, which was administered subcutaneously to lambs with NMD twice, with a 2-week interval. RESULTS: Before treatment, serum concentrations of fT3 and TT3 in lambs with NMD were lower than those of control group (P < .001), while serum concentrations of fT4 and TT4 in lambs with NMD were significantly higher than those of control group (P < .001, P < .01, respectively). Similarly, serum creatine kinase (CK), lactate dehydrogenase (LDH), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and alkaline phosphatase (ALP) values in lambs with NMD were significantly higher compared with those of control (P < .001, P < .001, P < .001, P < .01, and P < .05, respectively) before treatment. However, serum concentrations of Se and alpha-tocopherol in lambs with NMD were significantly lower compared with those of control (P < .001). After treatment (at day 30), none of the variables were significantly different between control and NMD lambs (P > .05). CONCLUSIONS AND CLINICAL IMPORTANCE: Nutritional myodegeneration in lambs is associated with abnormalities in serum thyroid concentrations. Abnormalities in serum thyroid concentrations can result from selenium deficiency in NMD lambs. Serum thyroid concentrations together with serum CK, LDH, AST, ALT, and ALP values can be considered additional tools in diagnosis and prognosis of NMD in lambs.