Physiology Commons^™

Maintaining Ewe Bodyweight For A Late Mating, T Marshall

Journal of the Department of Agriculture, Western Australia, Series 4

DEPARTMENT OF AGRICULTURE experiments have indicated that the bodyweight of ewes at mating can have a large bearing on lambing performance.

It appears that for every 10 lb. increase in pre-mating bodyweight, an increase of some 3 to 6 per cent, lambs born could be expected, depending on the lambing time.

Superphosphate Deficiency Raises Pasture Oestrogens, H G. Neil, T. Marshall

Journal of the Department of Agriculture, Western Australia, Series 4

A recent field experiment on established pastures at Esperance Downs Research Station has demonstrated a relationship between superphosphate application, pasture oestrogens and oestrogenic response in sheep.

Results of the experiment indicate that on phosphate deficient soils carrying oestrogenic clovers, the levels of oestrogenic materials in the pasture are increased if superphosphate applications are below those recommended for healthy pasture growth.

Mating Weaners Does Not Affect Future Ewe Performance, R J. Suiter, K. P. Croker

Journal of the Department of Agriculture, Western Australia, Series 4

Maiden ewes in Western Australia are usually mated in their second year because of supposed ill-effects of earlier mating on the ewe's future production. Mating at a younger age however, providing there was no reduction in future performance, would provide for an extra lamb drop and thus increase the lifetime output of ewes.

Information from various sources indicated that weaners could be successfully mated providing their bodyweights were satisfactory. This trial was carried out to test the results of mating weaners under Western Australian conditions.

Phosphate Applications Affect The Coumestrol Level Of Medics, T Marshall, R. J. Parkin

Journal of the Department of Agriculture, Western Australia, Series 4

Western Australia has a million acres of medics including various cultivars of barrel medic, Medicago truncatula, and strand medic, M. littoralis. Both species contain coumestrol, a chemical thought to have caused delayed conception and reduced twinning rates among grazing ewes in New Zealand.

No infertility has been reported among ewes grazing medic pastures in Western Australia, but coumestrol levels in both species have often been high enough to suggest the possibility of oestrogenic responses among sheep grazing them.

The Feed Year Approach To Dairying, P T. Arkell

Journal of the Department of Agriculture, Western Australia, Series 4

Dairy cows have different food requirements at different times of the year.

Cows in peak production require much more food per day than dry cows. It is a waste of money to feed a dry cow more than it actually needs for maintenance.

Equally, it is uneconomic NOT to feed a producing cow enough to give maximum production.