The growth rate and food conversion efficiency of fattening lambs given all-concentrate diets have been reported by Philip Preston and Greenhalgh (1964). The lambs were weaned abruptly at 8 weeks old and fed thereafter ad libitum on cereal and protein supplement. Owen, Davies and Ridgman (1965) have reported the same measures of performance for artificially reared lambs fed from 30 lb. to slaughter at 75 lb. on diets varying indigestibility. A considerable amount of information has been obtained recently on the nitrogen metabolism of young calves fed on all-concentrate diets (see Preston, Whitelaw, MacLeod and Philip, 1965, and Bowers, Preston, McDonald, MacLeod and Philip, 1965) but there is less information of a similar nature for lambs fed on such diets. The following experiment was carried out to assess the intake of energy and utilisation of dietary nitrogen by lambs fed ad libitum on three simple all-concentrate diets during the latter stages of fattening.

During 1963, pigs tested at the five pig progeny testing stations in Britain were examined and scored by each station manager for leg weakness at the end of test. Some 19 individual items were scored, the score being 0 if satisfactory, 1 if a mild fault and 2 if a serious fault. In addition an overall legs and action score was given, scoring on a scale from 1 to 6 points; in this case the higher the score the better the leg condition. Data were available on 1,240 Landrace and 1,892 Large White pigs (2 females and 2 castrated males per litter)from 128 and 202 sires respectively. Sex differences in incidence were small,most of them being less than a tenth of a standard deviation unit, and so the analyses were performed ignoring sex. To avoid any effects of differences in incidence and in scoring among stations and to avoid the effects of any trends in the scoring pattern over the year, the analyses were performed within three-monthly periods within stations.