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The birds were tested after 6 h of food deprivation, in the afternoon, to avoid the interaction between laying and feeding behaviour. The presence of birds at the feeder was recorded over a 30-rain period on a computer compatible system, thus allowing a detailed retrospective analysis of the birds' feeding behaviour (total feeding time, number of feeding bouts, mean length of feeding bouts) and of the reciprocal position of the birds.

The results showed that in the 5(1) and 100(1) conditions, the time spent feeding was longer than under any other condition. Consequently, competition may be far less important in the feeding behaviour of the hen than is usually assumed. Inter-individual attraction must be taken into account. When only limited feeding space is allowed, the main welfare problem is probably not increased competit ion but decreased synchronisa- tion of the group. This effect of decreased synchronisation should be evaluated from a welfare point of view.

TIME-BUDGETS AND SOCIAL INTERACTIONS IN HORSES: THE EFFECT OF DIFFERENT ENVIRONMENTS

M. KILEY-WORTHINGTON

School of Biological Sciences, University of Sussex, Sussex (Gt. Britain)

ABSTRACT

The behaviour of two groups of horses was recorded simultaneously for two 24-h periods. Horses from one group were housed together indoors while those from the other were kept in single stalls. Both groups had approximately the same space (12 m2/horse).

There was no significant difference in behaviour between the days, but the horses housed singly spent more time standing (48 compared to 28%) and sleeping (19 compared to 10%). Both groups had access to hay and straw ad libitum, and they showed no signifi- cant difference in the time spent eating (45% for those housed singly compared to 53% for those grouped). The number of interactions between individuals was not different (4.7 compared to 4.6/horse/h).

These time-budgets were then compared to those of (a) feral horses (Duncan, 1980) and (b) isolated horses fed restricted diets. There were no significant differences between the grouped and the feral horses. The isolated horses, however, spent far less time eating (25%) and more time standing (65%) than any of the other groups. With regard to social interactions, the feral horses had similar levels to the grouped horses. It was found that when the single-stalled horses were tied in a line, the number of interactions increased to l l / ho r se /h .

Dominance hierarchies were difficult to identify. However, when interactions were analysed in terms of aggression, affiliation, interest and direction, it was possible to build simple personality profiles which seemed more helpful in understanding group social organization than concepts such as "dominance hierarchies".

These results, together with previous work, suggest that two important factors control time-budgeting of stabled horses. These are (a) the availability of roughage which allows them to spend the majority of their time eating as they would under feral or pasture conditions, and (b) the availability of social contact. It is suggested that the inability to exercise these two behavioural "needs" are important contributory factors in the devel- opment of behavioural problems, particularly stereotypies, which are common in stabled horses.

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R E F E R E N C E

Duncan, P., 1980. Time-budgets of Carmargue horses. II. Time budgets of adult horses and weaned sub-adults. Behaviour, 72 : 26--49.

N E S T I N G M A T E R I A L P R E F E R E N C E O F D O M E S T I C H E N S

H.-U. H U B E R and D.W. F~)LSCH

Institute for Animal Production, Physiology and Hygiene Group, ETH-Zentrum, Zilrich (Switzerland)

A B S T R A C T

Thir ty-seven hens of a commercia l strain of White Leghorns, 16 f rom bat tery cages and 21 f rom a deep-li t ter house, were tested to see how various nesting materials would affect nest usage in a wire-floor house. The nesting materials were wire mesh, synthet ic grass ("as t ro tu r f" ) , wheat s traw and oat husks.

Of the deep-l i t ter hens, 76% preferred oat husks and 20% wheat straw. Of the bat tery- cage hens, 63% preferred oa t husks and 11% wheat straw. Some of the bat tery-cage hens laid their first eggs on the wire f loor of the house, most ly in corners. However , as t ime went by and the hens grew more familiar with their new surroundings, nest usage increased.

Most of the hens, regardless of their previous housing, showed a series o f f ixed behaviour pat terns during nest site selection. Typical ly , they were restless, hopped up on to the perches in f ront o f the nests, walked along these perches and pu t their heads into the nests. During nest site select ion, the hens seemed more a t t racted by nests with loose nesting material such as oat husks and wheat straw. Once the hens had selected nests and were si t t ing on them, it t ook most of them be tween 15 and 45 rain to lay an egg. During this t ime, they sat quie t ly on the nesting material. Quite of ten, they made some circular movements with their body, pecked at the nesting material and put particles of it beside and behind them. After laying, most hens f rom deep l i t ter left the nest within 30 rain, whereas the major i ty of hens f rom bat tery cages s tayed on the nest longer than 45 min.

The preference for loose nesting materials was conf i rmed in an addit ional exper iment in a commercia l deep-l i t ter house. When loose nesting material in some co lony nests was replaced with plastic net t ing or synthet ic grass, the hens no longer used those nests.

C R I M I N A L C A S E S R E L A T I N G T O C R U E L T Y T O A N I M A L S

W.T. J A C K S O N

M.A.F.F., Medwyn House, Mountfield Road, Lewes, East Sussex (Gt. Britain)

A B S T R A C T

The Law is one of the principle means of influencing animal welfare standards, and this paper deals with the fol lowing three aspects: (I) the impor tance of case law in