ARCHIVE FILE
This article was published in 1964
See the original document
INSTITUTE OF INSPECTORS OF STOCK OF N.S.W. YEAR BOOK.
Suspected Cobalt Deficiency in Lambs
E. A. FARLEIGH, B.V.Sc., Veterinary Inspector, Glen Innes.
INTRODUCTION.
Although reports over a number of years have been made of cobalt deficiency in various parts of Australia, particularly in the southern States (Lee 1950), as far as can be determined there has been no recorded finding of any condition resembling cobalt deficiency in sheep on the Northern Tablelands of New South Wales.
One property has been under observation for several years where unthriftiness of lambs has been in evidence and it is now suspected that cobalt deficiency is responsible.
The country is a medium quality undulating granite, and is top-dressed yearly with one cwt. of superphosphate and sown to cocksfoot, rye and white clover. The rainfall is 32-35", usually spread fairly evenly throughout the year and the property is situated approximately 14 miles East of Glen Innes at an altitude of over 3,500 feet.
SYMPTOMS.
Approximately 200 lambs, aged about 5 months, which had been weaned 2 months previously, were observed in April, 1962, to be losing condition and becoming so weak that when driven, lambs would collapse from apparent exhaustion. The lambs have been drenched with phenothiazene, thiabendazole and carbon tetrachloride, but no improvement could be detected and about 40% of the mob were observed to be gradually becoming worse, week by week. There was some evidence of lacrimation in a number of the lambs.
Post-mortem examinations were carried out and specimens for examination for worm burdens proved negative; blood calcium and magnesium were normal; liver copper, and serum G.O.T. were within normal limits. A heavy mortality in these lambs resulted.
The following year nearly 500 cross-bred lambs were raised and these were sent to market at an earlier age in order to prevent any possible deterioration in condition, but some late lambs were kept for a longer period and these also showed a similar fall in condition as seen in previous years.
In 1964, 550 cross-bred lambs were weaned in December and in February 250 lambs were forwarded to market, but it was noted that, of the remaining 300 lambs, quite a large percentage were starting to lose condition. The lambs were September October 1963 drop.
The symptoms appeared identical to those seen in 1962.
TRIAL:
It was decided to carry out a trial for possible cobalt deficiency and on the 4th March, 1964, the owner selected 80 lambs, which he considered typical of those affected. These were drafted into two groups (A & B). Group "A" consisted of 28 of the better lambs picked on condition as the sheep went through the race. Group "B" was made up of the remaining 52 poorer lambs.
Each group was then divided into two, eartagged, weighed and half of each group were injected intramuscularly with 250 micrograms of Vitamin B.12. As each sheep was weighed and eartagged a note was made as to its general condition and appearance. Quite a number were considered to be showing signs of anaemia and in the Group "B" (treated) six showed evidence of lacrimation, two being quite copious, while eleven of Group "B" (untreated) showed lacrimation, one being copious. In Group "A" lacrimation was only obvious in three sheep.
On the 14th March, 1964, a second injection of the same dose of Vitamin B.12 was given to those sheep treated on the 4th March, 1964, and all sheep were dosed with thiabendazole. On the 1st April, 1964, all sheep were again weighed. The results were quite spectacular and are shown in Table 1.
TABLE 1
| GROUP "A" | |||||||
|---|---|---|---|---|---|---|---|
| Treated 14 Head | Not Treated 14 Head | ||||||
| 4/3/64 Tot. Wt. lbs. | 1/4/64 Tot. lbs. | Gain lbs. | Av. Gain lbs. | 4/3/64 Tot. Wt. lbs. | 1/4/64 Tot. lbs. | Gain lbs. | Av. Gain lbs. |
| 817 | 978 | 161 | 11.5 | 803 | 909 | 106 | 7.6 |
| GROUP "B" | |||||||
| Treated 26 Head | Not Treated 26 Head* | ||||||
| 1374 | 1634 | 260 | 10.0 | 1392 | 1360 | 32 | 1.33 |
* Two sheep died between weighings excluded in calculation.
In Group "B" (untreated) the two lightest sheep, weighing 31 and 33 lbs., respectively, died during the month. Four sheep in this group lost weight and four sheep showed no change in weight. All sheep treated gained weight in both Groups "A" and "B". All sheep previously showing lacrimination in the treated group had improved and the face had dried, while those untreated still showed evidence of lacrimation. It is interesting to note that in Group "B" there were two sheep, which were 18 months old and had been culled out of the poor lambs 12 months before and were still in poor condition. One weighing 60 lbs. was treated and this sheep gained 10 lbs., while the other, weighing 77 lbs. and not treated, lost 3 lbs.
DISCUSSION.
The results of this trial appear to indicate that Vitamin B.12 has had a considerable effect in improving the condition of the sheep following treatment while those, which were not treated, showed little or no improvement. One month after the trial was completed it was noted that several more sheep in the control group had died and the owner stated that, on moving the mob, the ones with the yellow tags, which were untreated, were always the sheep that lagged behind and did not have the energy of those sheep which had green tags (treated).
Two months after the trial was completed it was seen that the treated sheep had deteriorated again and, once more the owner, to test the effect of Vitamin B.12, selected some of the lambs, which were untreated during the trial and injected them with Vitamin B.12. There was a decided improvement in these lambs and although they were not weighed their general condition improved and they were much stronger. Several lambs were seen to be almost blind with copious eye discharges and three weeks after the Vitamin B.12 injections were given there was no evidence of blindness to be seen.
SUMMARY
The first apparent record of possible cobalt deficiency in sheep in Northern New South Wales is recorded. Spectacular response to injections of Vitamin B.12 being obtained in a rather restricted trial. The symptoms and results of the trial closely parallel the findings of Sherman and Sutherland (1957).
ACKNOWLEDGEMENT.
It is desired to acknowledge the advice and assistance of Mr. B. Rutledge, B.V.Sc., of Glen Innes, in the planning of the trial.
References:
- Lee, H. J. (1950) — Aust. vet. J., 26: 152
- Sherman, K. D. and Sutherland, A. K. (1957) — Aust. vet. J., 33: 197