Linear measurements of six body dimensions were taken of Large White × Landrace pigs in the live-weight range of 1 kg to 286 kg. Logarithmic regression lines were fitted to the live-weight and measurement data. It was found that the body dimensions could be expressed as a function of live weight and that these equations agreed well with the simple allometric equation L = kW1/3, where linear dimension, W= live weight and k= an appropriate coefficient. It is suggested that these equations may provide a method of estimating the static space occupied by a pig and thus provide a basis for the development of space allocation recommendations in pig housing. It is also suggested that these principles may be applicable to other livestock.

A pilot study was conducted to investigate the possibility of using goats to manipulate the amount and composition of indigenous and improved vegetation on hill land in the west of Scotland.

Two vegetationally similar plots, each of approximately 0·6 ha, were used. Approximately 0·45 of each plot comprised sown ryegrass-clover pasture, the remainder being indigenous vegetation (principally Calluna vulgaris, Eriophorum and Tricophorum spp. with some Deschampsia, Molinia and Carex spp.). One plot was stocked with 14 yearling Anglo-Nubian goats and the other with seven mature Blackface sheep, the total weight of livestock on the two plots being the same (500 kg).

On the reseeded areas the proportions (± s.e. of difference) of ryegrass grazed by sheep and goats after 2, 5 and 8 weeks were 0·65 and 0·11 (0·075), 0·68 and 0·42 (0·112), and 0·77 and 0·58 (0·149), respectively; corresponding values for proportional clover cover were 016 and 0·45 (0·071), 0·16 and 0·38 (0·070), and 0·10 and 0·35 (0·070), respectively. The goats also actively grazed clumps of Juncus spp. and invading indigenous species which were not eaten by sheep.

On the indigenous areas the sheep grazed a higher proportion of Calluna than did goats (0·08 and 0·05) but grazed less E. vaginatum (0·07 and 0·13), E. angustifolium (0·04 and 0·11), and other indigenous species (0·21 and 0·36), respectively. The degree of utilization of grazed indigenous species by goats was also greater than that by sheep for all species except Calluna.

The results suggest that goats may have a use in some sheep production systems as an aid to the management of the varied plant communities of hill land, and particularly in the maintenance and further improvement of reseeded pastures.

The faecal recovery of chromium sesquioxide (Cr203) was examined in four experiments with non-lactating Ayrshire cows. In the first experiment Cr203-paper was given intraruminally twice daily to cows receiving a diet of hay. The mean recovery of the marker was 0·829 (s.d., (Mil, no. = 12). In the second experiment the marker was given as Cr203 powder to cows receiving a diet of hay and ground barley. The powder was mixed with the barley part of the diet and given in 24 hourly meals per day. The mean recovery of the marker was 0·944 (s.d., 0·079, no. = 8). In the third experiment cows receiving a hay and barley diet were given Cr203 powder suspended in ground-nut oil administered twice daily through a cannula in the duodenum. The recovery of the marker was 0·980 (s.d., 0·027, no. = 3).

In the fourth experiment ground straw impregnated with Cr203 was used as a marker in cows receiving a hay and barley diet. The marker was mixed with the barley and given in eight meals per day. The faecal recovery of Cr2()3 was 0-941 (s.d., 0·022, no. = 7). It is concluded that when Cr203 is used as an indigestible marker in studies with dairy cows its recovery in faeces may be variable and low due to retention of the marker in the stomach. In digestion studies with cows there are considerable advantages in favour of the use of Cr2()3-impregnated straw rather than Cr203 powder or Cr203-paper.

Down production of 93 feral, F1 and F2 cashmere-producing goats run in Victoria was investigated. The goats were visually assessed for down production and shorn. Their fleeces were evaluated for total fibre, down yield, fibre diameter, grease and moisture content. Analyses on down yield and fleece characteristics indicated that they compared favourably with those of traditional cashmere-producing countries. Mean down production ranged from 330 g for males to 148 g for females. Sampling at three body sites was accurate in determining total fleece measures and visual assessment proved a reliable screening technique for on-farm selection. Large variation was found in down production indicating the possibility of rapid genetic gain through selection.

ANIMAL PRODUCTION, Volume 34, Part 3, p. xiv