Copper oxide particles for grazing sheep

1983 ◽  
Vol 34 (6) ◽  
pp. 751 ◽  
Author(s):  
JP Langlands ◽  
JE Bowles ◽  
GE Donald ◽  
AJ Smith ◽  
DR Paull ◽  
...  
Keyword(s):  
Copper Oxide ◽  
Dose Rate ◽  
Copper Toxicity ◽  
Dose Rates ◽  
Hepatic Copper ◽  
Copper Status ◽  
Oxide Particles ◽  
Grazing Sheep ◽  
Copper Storage ◽  
Rate Of Decline

In a series of experiments aimed at evaluating copper oxide as a supplement, grazing sheep were dosed with varying quantities of copper oxide particles up to 64 g, and the toxicity, the rate of particle excretion, and copper storage in the liver and other tissues were recorded. The toxicities (LD50) of copper oxide particles were 1.17 and 1.80 g/kg liveweight for two groups of grazing adult fine-wool Merino sheep. Death usually occurred 88-96 days after the oral administration of the particles; mean hepatic copper concentrations of sheep dying from copper toxicity were 4122-4308 mg/kg DM. The rate of faecal copper excretion of copper-supplemented sheep, expressed as a percentage of the dose, was less when 50 g of particles were given than when the dose was 5 or 10 g, but excretion patterns were variable. The quantity of hepatic copper stored per g of copper oxide given declined as the dose increased from 0 to 32 g, but increased again at higher doses. Hepatic copper concentration reached a maximum 2-3 months after dosing and the rate of decline was positively related to dose rate; thus, large doses of copper are unlikely to extend the period of elevated copper status. Large doses also increased whole blood copper concentrations and elevated plasma aspartate transaminase activities; this was taken to indicate copper poisoning. Tissue copper concentrations from sheep given up to 64 g particles are reported; liver was the most sensitive to copper treatment. Copper contents of the lung and kidney also responded to copper therapy, but carcass components such as leg, shoulder and muscle did not. Weaned lambs given 2 g of particles (c. 0.13 g/kg liveweight) grew significantly faster than unsupplemented lambs. This dose rate was approximately one-seventh of that predicted to cause 5% mortality, and it is concluded that, at appropriate dose rates, this method of supplementation did not increase mortality or cause excessive increases in tissue copper concentrations, and could increase growth rate.

scholarly journals Copper Supplementation, A Challenge in Cattle

Animals ◽  
2020 ◽  
Vol 10 (10) ◽  
pp. 1890
Author(s):  
Marta López-Alonso ◽  
Marta Miranda
Keyword(s):  
Copper Deficiency ◽  
Copper Toxicity ◽  
Copper Metabolism ◽  
Copper Accumulation ◽  
Hepatic Copper ◽  
Copper Status ◽  
Large Numbers ◽  
Copper Supplementation ◽  
Key Points ◽  
Copper Storage

Ensuring adequate copper supplementation in ruminants is a challenging task due to the complexity of copper metabolism in these animals. The three-way interaction between copper, molybdenum and sulphur (Cu-Mo-S) in the rumen makes ruminants, particularly cattle, very susceptible to suffering from secondary copper deficiency. Paradoxically, excessive copper storage in the liver to prevent deficiency becomes a hazard when ruminants are fed copper-supplemented diets even slightly above requirements. While cattle were traditionally thought to be relatively tolerant of copper accumulation, and reports of copper poisoning were until recently somewhat rare, in recent years an increased number of episodes/outbreaks of copper toxicity in cattle, particularly in dairy cattle, have been reported worldwide. The growing number of lethal cases reported seems to indicate that copper intoxication is spreading silently in dairy herds, urging the development of strategies to monitor herd copper status and improve farmers’ awareness of copper toxicity. In fact, monitoring studies carried out on numerous samples collected from culled animals in slaughterhouses and/or diagnostic laboratories have demonstrated that large numbers of animals have hepatic copper concentrations well above adequate levels in many different countries. These trends are undoubtedly due to copper supplementation aimed at preventing copper deficiency, as dietary copper intake from pasture alone is unlikely to cause such high levels of accumulation in liver tissue. The reasons behind the copper overfeeding in cattle are related both to a poor understanding of copper metabolism and the theory of “if adding a little produces a response, then adding a lot will produce a better response”. Contrary to most trace elements, copper in ruminants has narrow margins of safety, which must also be formulated considering the concentrations of copper antagonists in the diet. This review paper aims to provide nutritionists/veterinary practitioners with the key points about copper metabolism in cattle to guarantee an adequate copper supply while preventing excessive hepatic copper loading, which requires à la carte copper supplementation for each herd.

Trace element nutrition of grazing ruminants. 3. Copper oxide powder as a copper supplement

1989 ◽  
Vol 40 (1) ◽  
pp. 187 ◽  
Author(s):  
JP Langlands ◽  
GE Donald ◽  
JE Bowles ◽  
AJ Smith
Keyword(s):  
Copper Oxide ◽  
Trace Element ◽  
Oxide Powder ◽  
Edta Complex ◽  
Hepatic Copper ◽  
Trace Element Nutrition ◽  
Oxide Particles ◽  
Grazing Sheep

Hepatic copper (Cu) storage was determined in grazing sheep and cattle supplemented with copper oxide powder, oxidized Cu particles or Cu-calcium EDTA. Cu storage was significantly increased when particles or the EDTA complex were given, but responses in hepatic Cu concentration were small in animals given copper oxide powder. Sheep dosed with copper oxide particles retained particles in the abomasum at 44 days from dosing, but those given copper oxide powder did not retain measurable quantities in the abomasum and excreted about half the dose in the faeces within 4 days of administration.

Trace element nutrition of grazing ruminants. 1. Degree of oxidation, diet, frequency of dosing and location in the gastro-intestinal tract as factors affecting the ability of oxidized copper wire to promote hepatic copper storage

1986 ◽  
Vol 37 (2) ◽  
pp. 179 ◽  
Author(s):  
JP Langlands ◽  
JE Bowles ◽  
GE Donald ◽  
AJ Smith
Keyword(s):  
Copper Wire ◽  
Liver Weight ◽  
Factors Affecting ◽  
Dose Rates ◽  
Cu Content ◽  
Hepatic Copper ◽  
Degree Of Oxidation ◽  
Trace Element Nutrition ◽  
Copper Storage ◽  
Gastro Intestinal Tract

Factors affecting the ability of oxidized copper (Cu) wire to promote hepatic Cu storage in penned and grazing sheep were examined in two experiments. The incorporation of molybdenum (Mo) and sulfur (S) into the diet did not reduce hepatic Cu storage, but storage was negligible when elemental Cu was used as the supplement, and it is suggested that dose rates could be manipulated by varying the extent of oxidation of the particles. Oxidized particles were relatively ineffective when held in the rumen in a nylon bag, and some of the variability in the pattern of hepatic Cu storage after dosing is likely to be associated with the rate of clearance of the particles from the rumen; there was no evidence that particles were rendered ineffective by being held in the rumen for up to 6 weeks. Excessive hepatic Cu concentrations were observed in some sheep and were attributed to the quantity of supplement given, the high Cu content of the basal diets, and to the failure to scale the dose in proportion to liver weight or liveweight. Dosing at 6-monthly intervals reduced variability in hepatic Cu concentration through time, but the strategy may lead to unacceptable hepatic Cu concentrations unless dose rates or the extent of oxidation of the particles are appropriately reduced.

Copper status of sheep grazing pastures fertilized with sulfur and molybdenum

1981 ◽  
Vol 32 (3) ◽  
pp. 479 ◽  
Author(s):  
JP Langlands ◽  
JE Bowles ◽  
GE Donald ◽  
AJ Smith ◽  
DR Paull
Keyword(s):  
Copper Sulfate ◽  
Copper Concentration ◽  
Sodium Molybdate ◽  
Sheep Grazing ◽  
Biopsy Technique ◽  
Black Sheep ◽  
Hepatic Copper ◽  
Copper Status ◽  
Copper Storage ◽  
Molybdenum Concentration

Varying quantities of sodium molybdate, superphosphate and copper sulfate were applied to 30 plots, and changes in hepatic copper concentration in sheep grazing these plots were measured by using a biopsy technique. A relationship between changes in hepatic copper storage and the copper and sulfur x molybdenum concentrations in the green forage on offer was calculated. This relationship was used to calculate the quantity of copper in green forage on offer necessary to maintain hepatic copper concentration constant when the forage varied in sulfur and molybdenum concentration. In a second experiment sodium molybdate was applied to pasture grazed by sheep at rates varying from 0 to 2000 g molybdenum per ha. Black sheep grazing pasture dressed with 2000 g molybdenum per ha, grew white wool for four months following molybdenum application; this corresponded to the period when molybdenum concentration in herbage on offer was greatest. There were also changes in blood, wool, kidney and liver composition following molybdenum application but these were small when molybdenum was applied at the usual commercial rate. The results of both experiments suggest that the application of molybdenum to pasture at commercial rates is unlikely to induce copper deficiencies in grazing sheep.

Oxidized copper wire particles for copper therapy in sheep

1982 ◽  
Vol 33 (6) ◽  
pp. 1073 ◽  
Author(s):  
GJ Judson ◽  
TH Brown ◽  
D Gray ◽  
DW Dewey ◽  
JB Edwards ◽  
...  
Keyword(s):  
Copper Oxide ◽  
Copper Wire ◽  
Significant Proportion ◽  
Clinical Signs ◽  
Copper Toxicity ◽  
Liver Copper ◽  
Copper Status ◽  
Copper Supplementation ◽  
Copper Therapy ◽  
Higher Doses

Ninety Merino weaner sheep were assigned to one of six groups on the basis of liveweight and liver copper concentrations. Sheep in four groups each received one oral dose of oxidized copper wire particles, viz. 2.5, 5, 10 or 20 g per animal. Sheep in another group each received a subcutaneous injection of 12 mg copper as diethylamino cupro-oxyquinoline sulfonate and another group of sheep did not receive any copper supplement. Liver copper concentrations responded positively to copper oxide load. The 2.5 g dose of copper oxide wire was more efficacious than the commercial injectable product in raising copper status, but the higher doses of oxide raised liver copper concentrations to values similar to those recorded in cases of copper poisoning. Copper concentrations in blood plasma, muscle and kidney were not altered by the copper load. No clinical signs, nor biochemical or histological evidence of acute copper toxicity, were found. Liver copper values fell in all sheep from 10 weeks after copper therapy until the end of the trial at 50 weeks post-therapy. Over this period of 40 weeks, the rate of mobilization of liver copper was linear and was positively related to the initial concentration of copper in the liver. A significant proportion of the oxidized copper wire dosed to sheep was recovered in the forestomachs and abomasa of selected sheep 4 weeks after dosing. No evidence of abomasal damage due to particles could be established. It is concluded that oral dosing of oxidized copper wire is a safe and effective method of copper supplementation to sheep.

An evaluation of copper-containing soluble glass pellets, copper oxide particles and injectable copper as supplements for cattle and sheep

1991 ◽  
Vol 31 (2) ◽  
pp. 165 ◽  
Author(s):  
JD McFarlane ◽  
GJ Judson ◽  
RK Turnbull ◽  
BR Kempe
Keyword(s):  
Copper Oxide ◽  
Peat Soil ◽  
South Australia ◽  
Individual Variability ◽  
Control Group ◽  
Dose Rates ◽  
Soluble Glass ◽  
Severe Deficiency ◽  
Oxide Particles ◽  
High Concentrations

The efficacy of 3 copper (Cu) supplements in maintaining adequate Cu status in Shorthorn heifers and Merino wethers was investigated in 3 experiments on alkaline peat soils in the South East of South Australia. The Cu supplements used were: soluble glass pellets containing Cu; copper oxide particles (CuO); Cu as a subcutaneous injection. Pasture contained moderate to high concentrations of molybdenum (Mo) (2.9-12.3 mg/kg), moderate Cu (3.8-8.7 mg/kg) and adequate sulfur (>1.7 g/kg) to limit the absorption of dietary Cu in ruminants. Shorthom heifers with normal Cu status were given 1 of 6 treatments (no Cu; 2 glass pellets; CuO at 3 doses; Cu injection) and introduced to the pasture (experiment 1). There was no liveweight response to any supplement. Relative to untreated heifers, mean liver Cu concentrations were raised only in heifers receiving the glass pellets or the highest dosage of CuO (20 g). The glass pellets maintained an adequate mean liver Cu concentration for at least 44 weeks but the CuO was effective for less than 24 weeks. Hypocupraemic heifers given 1 of 3 treatments (2 glass pellets; CuO; Cu injection) were significantly heavier (P<0.05) than the untreated heifers after 30 weeks (experiment 2). Mean plasma Cu concentrations were adequate at 30 weeks in the glass pellet and CuO groups, but mean liver concentrations indicated severe deficiency in all groups at 30 weeks. There was considerable individual variability in response to the glass pellet and CuO particle treatments, possibly due to the partial regurgitation of some of these orally dosed supplements. Merino wethers with adequate plasma and liver Cu concentrations received 1 of 5 treatments (no Cu; 1 glass pellet; 2 glass pellets; CuO; Cu injection) and were then grazed on a peat soil for a period of 1 year. Plasma Cu concentrations in the control group only indicated hypocupraemia at week 42. Liver Cu concentrations were higher (P<0.001) in all supplemented groups from week 18 to after week 30. Under the conditions of the experiments, 20 g CuO (the suggested dose) for the glass pellets or a single Cu injection were not sufficient to maintain the Cu status of heifers for 1 year. Repeat treatments or higher dose rates were required. The recommended dose rates of the supplements were adequate for wethers.

Fenbendazole as a method for measuring supplement intake in grazing sheep

2012 ◽  
Vol 52 (12) ◽  
pp. 1142 ◽  
Author(s):  
F. J. Fishpool ◽  
L. P. Kahn ◽  
D. J. Tucker ◽  
J. V. Nolan ◽  
R. A. Leng
Keyword(s):  
Dose Rate ◽  
Plasma Concentrations ◽  
Area Under The Curve ◽  
Gastrointestinal Nematode ◽  
Good Representation ◽  
Dose Rates ◽  
Internal Parasites ◽  
Grazing Sheep ◽  
The Relationship ◽  
Supplement Intake

Currently there is a need for an accurate and non-hazardous method to measure individual intake of a supplement in grazing sheep over a prolonged period. This paper examines the potential of fenbendazole (FBZ) as a marker of intake. The following five experiments aim to determine the relationship between oral ingestion of FBZ and the plasma concentrations of FBZ and its metabolites oxfendazole (OFZ) and FBZ-sulfone (SUL) after single, multiple and daily doses both in housed and grazing sheep and sheep infected with internal parasites. The results from these experiments indicate that OFZ+SUL concentrations in plasma are dependent on FBZ dose rate in housed and grazing animals with differences evident between different dose rates (P < 0.001). Variability of OFZ and SUL concentrations increase in grazing compared with housed animals. Area under the curve of metabolite concentrations was also shown to indicate dose rate regardless of the timing and frequency of dose. Stepwise regressions indicated that sampling every 48 h gave a good representation of area under the curve for different dose rates (R2 = 0.951, P < 0.001). A significant separation of treatment means was achieved when samples were taken every 48 h and pooled during daily dosing with FBZ (P < 0.001). Finally gastrointestinal nematode infection did not affect OFZ and SUL concentrations after daily doses of FBZ. The results from these experiments indicate that FBZ is a useful and accurate marker of supplement intake in grazing animals.

scholarly journals Radiation Awareness for Endovascular Abdominal Aortic Aneurysm Repair in the Hybrid Operating Room: An Instant Operator Risk Chart for Daily Practice

2021 ◽  
pp. 152660282110074
Author(s):  
Quirina M. B. de Ruiter ◽  
Frans L. Moll ◽  
Constantijn E. V. B. Hazenberg ◽  
Joost A. van Herwaarden
Keyword(s):  
Radiation Dose ◽  
Dose Rate ◽  
Effect Size ◽  
Radiation Risk ◽  
Dose Limit ◽  
Access Site ◽  
Femoral Access ◽  
Dose Rates ◽  
Rate Prediction ◽  
Operator Dose

Introduction: While the operator radiation dose rates are correlated to patient radiation dose rates, discrepancies may exist in the effect size of each individual radiation dose predictors. An operator dose rate prediction model was developed, compared with the patient dose rate prediction model, and converted to an instant operator risk chart. Materials and Methods: The radiation dose rates (DRoperator for the operator and DRpatient for the patient) from 12,865 abdomen X-ray acquisitions were selected from 50 unique patients undergoing standard or complex endovascular aortic repair (EVAR) in the hybrid operating room with a fixed C-arm. The radiation dose rates were analyzed using a log-linear multivariable mixed model (with the patient as the random effect) and incorporated varying (patient and C-arm) radiation dose predictors combined with the vascular access site. The operator dose rate models were used to predict the expected radiation exposure duration until an operator may be at risk to reach the 20 mSv year dose limit. The dose rate prediction models were translated into an instant operator radiation risk chart. Results: In the multivariate patient and operator fluoroscopy dose rate models, lower DRoperator than DRpatient effect size was found for radiation protocol (2.06 for patient vs 1.4 for operator changing from low to medium protocol) and C-arm angulation. Comparable effect sizes for both DRoperator and DRpatient were found for body mass index (1.25 for patient and 1.27 for the operator) and irradiated field. A higher effect size for the DRoperator than DRpatient was found for C-arm rotation (1.24 for the patient vs 1.69 for the operator) and exchanging from femoral access site to brachial access (1.05 for patient vs 2.5 for the operator). Operators may reach their yearly 20 mSv year dose limit after 941 minutes from the femoral access vs 358 minutes of digital subtraction angiography radiation from the brachial access. Conclusion: The operator dose rates were correlated to patient dose rate; however, C-arm angulation and changing from femoral to brachial vascular access site may disproportionally increase the operator radiation risk compared with the patient radiation risk. An instant risk chart may improve operator dose awareness during EVAR.

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