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This article was published in 1966
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INSTITUTE OF INSPECTORS OF STOCK OF N.S.W. YEAR BOOK.
Observations on the 1965 Drought in Cooma-Bombala P.P. Districts
R. C. DENYER, B.V.Sc., Veterinary Inspector, Cooma
DURATION OF DROUGHT
No useful rain fell over most of the districts between mid-December, 1964, and the end of July, 1965. Good rain fell in August, 1965, and useful rains were received until December.
Response to the August rain was limited, due to low temperatures, but very valuable. Feeding was still widely practised until the end of September.
Not all owners in any part of the area experienced drought losses - to that extent, it was a year testing management. Many owners kept herds and flocks intact by using home-grown fodder.
Losses were not, in the vast majority of cases, associated with overstocking. One sampling of holdings revealed this sort of situation:
(a) Owners who experienced heaviest losses mostly carried less than one sheep equivalent per acre.
(b) Owners who experienced no significant starvation losses in many cases carried from 11/25 sheep equivalent per acre but on improved pastures.
Cattle losses:
These were light overall but more cattle than normal were sold from the district. Such losses as did occur were associated in nearly all cases with failure to control infestations of liver fluke and lice.
Sheep losses:
Sheep losses attributable to drought as estimated in November were:
| deaths | 40,000-60,000 |
| excess sales | 5,000-10,000 |
| lower lambing | 35,000 |
| 80,000-105,000 |
Returns coming to hand suggest the fall in sheep population may be nearer 130,000 of 1,300,000 sheep on hand (owners' figures) as at 31/12/64.
Weaners and breeding ewes suffered heaviest mortalities. Contributing factors were:
(a) Poorly grown weaners showed poor survival. Bigger weaners possibly of the order of 50 lb. live weight survived more like mature dry sheep.
(b) Breeding ewes in backward store condition a month pre-lambing, mostly suffered losses in August, but late lambers were unaffected. Pre-lambing shearing was associated with heaviest losses. Concentrate feeding without hay would not raise body weights. Improvement followed two weeks after early August rain.
(c) Snowfalls, which in some areas totalled 4-5 in. and which on three occasions covered the ground for five to seven days, added to losses. Better fed sheep in the same areas were unaffected. Post-lambing feeding was necessary for a short time only, and this situation was met in many cases by the use of feed blocks.
(d) For a short period of about two weeks prior to the August rain, abortions occurred on a small number of holdings. In some, uterine pipettes were sterile, in others, coliforms, apparently post partum invaders, were associated with mortalities. Erosions of the uterine villi in the periphery of the cotyledons were seen.
UTILISATION OF UREA
The utilisation of urea was not examined critically but several field observations can be made.
High urea blocks were used extensively for both sheep and cattle and were generally reckoned to be of great assistance for cattle on adequate roughage. On basalt country, carrying tussocky grasses, cattle generally received no other supplement.
Low urea blocks were used fairly widely especially on the higher granite country. The granite areas generally did not secure spectacular benefit from urea supplements,
There was very little evidence of urea toxicity even where no precautions were taken. Urea intake tended to be universally proportional to the amount of superphosphate which had been spread.
Urea and grain of the Shepherd's mix type was not widely used, but gave very satisfactory results. Ingredients were much cheaper than purchased supplements, but labour costs were high. Results obtained with this type of mix were substantially the same as those from "Rumevite" (R).
Where "Rumevite" was provided for weaners, intake tended to stabilise at ¾ ozs. per day and was often an adequate supplement on dry feed. Weight gains did not occur but survivability was good.
GRAIN POISONING
Grain poisoning on sheep nuts was responsible for substantial losses made up of light losses on many holdings. These conditions were apparently met state-wide. Response to bicarbonate of soda was always good when early treatment was possible. Twice weekly feeding had to be temporarily suspended following snow covering of the ground for three days or more. As the wheat content of nuts rose, the danger of grain poisoning increased.
SUGGESTIONS FOR FUTURE DROUGHT FEEDING IN THE AREA
1. Breeding Ewes:
Especially where good quality hay is not likely to be available for pre-lambing feeding, body weights should be maintained at a higher level during pregnancy than has been advocated.
2. Vitamin A supplementation:
I am not satisfied that we can recognise all manifestations of vitamin A deficiency and feel that we should not so vigorously oppose its use while recognising that clinical manifestations were in fact recognised and corrected in many cases.
3. Wheat Feeding:
There is little doubt that more wheat would be fed in another drought to both sheep and cattle. In this area digestive disturbances associated with nut feeding were frequent and often serious, and the situation with wheat feeding was generally more favourable.
4. Urea Supplementation:
With all its limitations, urea appears to have an important place particularly for cattle and especially on the basalt country. Abundant roughage or grain feeding must be associated with successful exploitation of urea, and this is common on much of the Monaro.
5. Control of Rabbit Infestations:
Infested country can be confidently expected to produce earliest, most continuous and heaviest mortalities.