A further experiment in a series of trials to look at the effects of treating straws on their feed values, and the responses to different supplements was carried out in the winter of 1982-83. The treatments were:-

1. 1) Untreated barley straw (DBS) plus 1.5 kg rolled barley/urea per day

2. 2) Ammonia treated barley straw (TBS) alone

3. 3) Ammonia treated wheat straw (TWS) alone

4. 4) Ammonia treated wheat straw (TWS) plus 0.5 kg rolled barley

5. 5) Ammonia treated wheat straw (TWS) plus 0.5 kg soya bean meal

6. 6) Ammonia treated wheat straw (TWS) plus 0.25 kg rolled barley and 0.25 kg fishmeal

There were 7 Hereford x Friesian cows per treatment, all mature animals (third calvers or more) calved in May, bulled with a Charolais bull in July and calves weaned off and cows yarded in November 1982. The trial ran for 145 days from 25 November 1982 to 19 April I983 covering about months 4 to 8 of pregnancy. They were group fed.