ARCHIVE FILE
This article was published in 1981
See the original document
Mineral Deficiency in Cattle
P. Andrew, B.V.Sc., Veterinary Inspector, Hay
HISTORY
The deficiencies investigated occurred in a herd of approximately 200 hereford and hereford shorthorn cross cattle in the Merriwagga area of the Hay Pastures Protection Board. Merriwagga has an undulating Mallee landscape with an average rainfall of 15" per year.
The area consists of red sandy loam soil with an occasional outcrop of small limestone pebbles from the parent layer. This soil is subject to leaching and is used for dry land wheat farming or grazing native pastures, introduced medics and stubble.
CLINICAL SIGNS
All cattle were in poor condition with 10-15% being extremely poor. The general appearance was one of stunted growth, haunched backs with a dry, coarse coat. Pure herefords had a yellow tinge to the coat colour, yet this was not as noticeable in the crossbreds.
Approximately 5% showed lameness (peg-legged), some with joint crepitus and old fracture wounds. Incisor teeth were worn with the front incisors often exhibiting an uneven pattern of wear which suggests bone or limestone chewing.
Prior to the testing a number of cows had become recumbent but responded to calcium borogluconate. Recumbency re-occurred within two days.
Calves at foot were in good condition.
TRIAL PROCEDURE
The trial consisted of taking 18 blood samples initially and 40 blood samples two months later. These 40 samples comprised repeat bleeds of the first 18 cattle. Two months was considered the minimum period required to show improvement in this type of country. All cattle sampled were aged via dentition, wet and dried and pregnancy tested in case a history could help with the final result.
Prior consultation with the Regional Laboratory was essential as a number of valuable points were learnt before the trial even began. These were:-
a. A limited number of samples could only be forwarded and analysed.
b. The laboratory requested the sample within 24 hours.
c. Each vacutainer had to be a minimum of ½ to ¾ full.
d. Pre-warn laboratory staff the day prior testing so samples get priority treatment and avoid bleeding close to the weekend.
Failure in the trial existed in using the owner's ear tagging method. Considerable duplication was found on the second bleed but fortunately history helped clarify some of this double identification.
This duplication may have been detected on the first bleed if one person was responsible for recording. Also once improvement was noticed in the cattle by the owner, there was no desire to continue the trial.
Advice given to the owner, after the first bleed was:-
a. Continue use of Calcium borogluconate on downer cows.
b. Begin the use of Femafos lick supplementation. (Ca/P)
c. Wean all eligible calves at foot (Calves up to the age of yearlings were still unweaned).
This procedure was completed on the same day of sampling.
Ca/P imbalance was suspected prior to the trial as this area has other recorded cases dating back several years.
TRIAL RESULTS
As per graphs
INTERPRETATION
A general improvement was noticed in all cattle at the second bleeding. This appears to be reflected in the results obtained - for Phosphate, Copper, and Magnesium plus the percentage of animals with multiple deficiencies decreased significantly.
Calcium results were atypical of the general trend, this may be due to:-
a. Use of blood as a measure of Ca detection being unreliable.
b. A complex and as yet poorly understood calcium cycle.
c. Factors causing deficiency -i.e.. Lactation, stress, season outweighing replacement.
As a general observation involvement of magnesium and copper deficiency are more prevalent where combinations of various deficiencies occur. This can be noted where the graphs showing multiple deficiencies are analysed on an element basis.
This suggests only a trace deficiency of these elements in the majority of the population as supported by the individual element graphs.
CONCLUSION
The mallee area of the Merriwagga region is a distinct Phosphate Calcium deficient region with marginal deficiencies in Copper and Magnesium.
These deficiencies are fluctuating and generally accentuated by stress, poor seasons and poor management.
Combinations of marginal deficiency or deficiencies of the various elements individual animals.
