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This article was published in 1975
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Copper in Cattle
G.R. Gee, B.V.Sc., Veterinary Inspector, Kempsey
In this paper I intend to discuss some aspects of the diagnosis and treatment of suspected copper deficiencies in cattle.
In the past a diagnosis of copper deficiency in cattle has often been made on the basis of
a). herd history
b). clinical signs
c). area information
d). analysis of tissues and feeds
e). response to therapy.
The herd history may include such signs as depression of growth, loss of weight, reduced production, disturbed oestrus and/or reproductive failure and occasionally bone fractures as a result of acute osteoporosis.
In Blood and Henderson, it is stated that 'field diagnosis depends on recognition of distinctive signs of copper deficiency and clinical response to treatment with copper. Of the various signs depigmentation of hair is probably the most sensitive indicator of a copper deficiency.'
On an area basis, diagnosis may not be so simple, as Dr. P. Mylrea at Wollongbar D.V.L. claimed in a reported dated 20th October, 1972, that on information available to that date it was not possible to determine any area or seasonal occurrence.
However, field veterinarians on the North Coast firmly believe that they can determine areas within which copper deficiencies are likely to occur. In my district the rain deficient areas are the
1). Coastal sandy soils, poor in organic matter and heavily weathered.
2). Marine and river silts.
3). Swamplands - nowadays heavily drained.
This would include almost all the coastal strip extending from the sea inland for 10 - 20 miles.
Apart from this narrow coastal strip, certain areas along river and creek valleys seem also to be associated with copper deficiency in the local cattle. In many cases these areas are associated with old mine workings - mainly antimony, and it is thought that these soils may contain excess molybdenum or inorganic sulphates which render the copper unavailable to pasture and thus to cattle.
As the Port Macquarie Pastures Protection Board District is nowhere much wider than 50 miles from coast to western boundary, and contains four major rivers with numerous creek tributaries (and numerous abandoned mine-workings) I tend to regard soils in most of the district: as being copper deficient. There would however be exceptions in the case of the deep red soils of the Comboyne and Dorrigo Plateaux and parts of the Nambucca district.
CLINICAL SIGNS
Analysis of tissues and feeds provides additional information that may assist us in reaching a diagnosis of copper deficiency, affecting a group of cattle on a particular property.
If one accepts the figures of 0.07 to 0.20 mg. Cu/100 ml plasma as being the normal range, then less than 0.05 mg Cu/100 ml may be regarded as evidence of a deficiency. In my experience, very few blood samples from suspected cases show levels less than 0.05 mg Cu/100 ml, however a large number of samples show levels within the 0.05 -0.07 mg Cu/100 ml range. Strangely enough, it is not always the cattle showing marked symptoms that produce the lowest levels. For a period I routinely collected blood samples from clinical cases and apparently normal cattle on the same property. The normal cattle invariably showed the lowest blood copper levels, ( down to 0.038 mg) whilst the clinical cases were within the 'normal' range. Yet when treated with copper by mouth or by injection, the clinically affected animals responded visibly, whilst cattle that appeared normal (despite the low blood copper levels) did not noticeably improve. The lowest figure recorded for a blood sample was 0.024 mg Cu/100 ml - SN 59/3737.
As a result I came to regard blood samples as being somewhat unreliable so far as individual cattle were concerned, although possibly a good guide on a herd or property basis. Liver biopsy was considered but never attempted.
No attempt was made to determine seasonal fluctuations in blood copper levels. Mostly the clinical cases occurred during or following prolonged spells of wet weather. Invariably there were added problems of poor nutrition and internal parasites. The parasitic problem was investigated and treated, and nutrition improved where possible. However, the farmer aiming for maximum benefit with least cost and effort usually drenched the calves with a bluestone solution or administered copper glycinate by injection.
No attempt has been made to determine the Cu content of pastures or soils. However, inquiry was always made from the farmers as to whether Molybdate superphosphate has been applied to the pastures. Years ago when it first become available, Molybdate Superphosphate produced such good pasture responses that farmers used it to excess, this overuse was accompanied by some of the side effects of hypocuprosis, namely infertility in dairy cows grazing the fertilised pasture, There was no evidence of depigmentation, scouring loss of condition etc. The cows looked well and milked reasonably well, but would not conceive until given a copper supplement. This failure to conceive was very evident when herds were on partial or total A.I.
Response to therapy is, to my mind, the best guide as to whether a copper deficiency problem exists in a herd. Generally speaking there is always some degree of response to supplementation with copper, even in cattle that are not showing obvious clinical signs of a deficiency. Only where prolonged Cu deficiency has caused irreversible damage to the nervous system or myocardium does supplementation fail to restore normality.
Attempts to supplement cattle via the pasture with annual application of 5 lb copper sulphate per acre is reported to be effective in some deficient areas.
However, treated pasture needs to be left for three weeks or until after heavy rain to avoid copper poisoning. I only know of one attempt to add copper to pastures and results were hard to assess in the stock. Certainly it did not appear to improve the pasture.
The addition of copper sulphate to drinking troughs was quite common on parts of the lower Macleay. Apart from corroding metal troughs and piping, the cattle tended not to drink the water. At very low concentrations the copper sulphate kept algae and water insects away and thus it was used in concrete troughs in council saleyards to keep the water clean.
Oral dosing with copper sulphate solution (4g for adult cattle) weekly is effective, but time consuming and dangerous. However if cattle are scouring profusely, (e.g. Peat Scours) several such drenches do seem to be effective in stopping scouring.
Nowadays few owners drench with copper sulphate solution. Mostly stockowners anticipate the need for copper supplementation by providing home made licks along the following lines:—
| DAILY REQUIREMENTS | |
|---|---|
| 50 parts Bonemeal 50 parts Salt 1 part Bluestone |
50 mg/day/ per Beast 1 lb. 100 : cattle for 100 days |
These licks are placed in paddocks in wooden or concrete troughs covered to protect from rain. My aim is to have these licks continuously presented before the cattle. At times the cattle consume the licks in large quantities, at other times they lick them occasionally or ignore them altogether. There does not appear to be any uniform pattern over the district as a whole, that I can determine although demand seems to increase in wet autumns.
Where cattle are run on reclaimed swamp soils (peat soils) continuous supplementation with licks containing up to 3% copper sulphate appears sufficient to prevent the appearance of obvious signs of copper deficiency. However, stockowners find that growth rate and appearance of young cattle is improved by an injection every 4 - 6 months of a copper glycinate compound (400 mg, containing 120 mg Cu.). A marked local reaction occurs at times - meat animals should be injected sub-cutaneously, and breeders intra-muscularly.
I suspect (that many stockowners do not administer copper simply to improve growth rate in young cattle. In recent years with the swing towards Herefords, amongst large and small beef breeders, it is most noticeable at saleyards that the rich red coated cow and calf always sold for a few dollars more than yellow coated cows and calves of similar age and size. For this reason alone it is a wise economic procedure for the owner to supplement cattle with copper where levels are deficient or marginal. Proof of increasing use of copper supplements for cattle in my area come from veterinarians and produce stores, both reporting that sales of copper glycinate for injection and copper sulphate for licks have doubled in the past two years and showed steady increases year by year before that.
I regard copper as the 'wonder drug' for cattle on the Mid-North Coast. It never will be a substitute for good feed but it certainly is a valuable additive to that which passes for pasture up our way.