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Furnished cages for laying hens have advantages in allowing normal behaviors and maintaining productivity. As the cost of introduction is a barrier for farms, we developed furnished cages that re-use conventional cages. To determine the minimum and functional cage design, we compared six designs, combinations of two floor designs (artificial turf or wire cage floor) and three screening designs in the integrated area (no screening, one entrance side or four sides). In total, 144 hens were used, and we measured behavior, physical condition and productivity. Comparing the floors, the percentages of hens performing dust-bathing and laying eggs in the integrated area were higher in cages with turf than wire floor (P

Dairy calves are commonly vocal after separation from the cow and during the following weeks while they are fed milk. This study examined the functional and motivational basis for such vocalizations. In one experiment, we found that 14 newborn calves called on average (±S.E.M.) 31.4 (±7.0) times per day when fed according to conventional management (i.e. twice daily for a total of 5 l during 24 h). In contrast, when calves were fed every 4 h and received 8 l of milk per day they called only 5.0 (±3.4) times over that period. Calls were also higher in fundamental frequency when calves were fed conventionally than when fed more milk, more often (120.6±2.2 versus 109.0±3.1 Hz). In a second experiment, we found that 19 five-week-old calves deprived of milk called on average 9.9 (±2.1) times during a 3 h period compared to 0.3 (±0.5) times when they had ad libitum access to milk. These results indicate that the vocalizations of milk-fed calves are related to milk feeding practices and that vocal behaviour may be useful in developing methods of separation and weaning that are less distressing for the calf. Analysis of call duration, fundamental frequency and frequency of maximum amplitude indicated that calls of calves in both experiments were individually distinctive, providing a potential basis for recognition of calves by cows.

Weight gain, milk intake, starter intake and number of days with diarrhoea were measured for individually housed Holstein calves offered milk twice daily by bucket at 5% of body weight per feeding (n=11) or ad libitum from a teat (n=12) from birth until 4 weeks of age. Mean weight gains during the first 2 weeks were 0.36 and 0.85 kg/day and during the next 2 weeks were 0.58 and 0.79 kg/day respectively. These differences were probably the result of higher milk consumption by teat-fed versus bucket-fed calves, which occurred in all 4 weeks. Starter consumption was negligible until 3 weeks of age for both groups, but the bucket-fed calves consumed more than teat-fed calves (0.25 versus 0.11 kg/day) during week 4. Milk drinking behaviour was studied in detail for eight teat-fed calves over 24 h. Total feeding time was 47 min. All individuals took their largest meals after new milk was provided in the morning (4.7 kg at 6.4 g/s) and after milk was added in the afternoon (3.2 kg at 5.0 g/s); 74% of total daily intake was consumed in these two meals. Calves that drank more also drank faster (r=0.78 for morning meals, 0.90 for afternoon meals). Intake rate varied little over the course of large meals, although it tended to decelerate towards the end of the meal. Calves consumed the first meal of the day in 13 min, during which they were attached to the teat for 80% of the time. These meals comprised, on average, 25 individual sucking events of 25 s duration, interspersed by gaps of 7 s. Calves occasionally butted the teat, normally during the middle of the meal, and the frequency of butting correlated positively with intake rate (r=0.80). Feeding calves ad libitum from teats allows them to determine their own intake patterns while improving performance compared to conventional bucket feeding.

Two experiments examined the effect of age and diet on behavioural responses of piglets to separation from the sow. In Experiment 1, the vocalizations of piglets were recorded during short term (10 min) isolation from the sow and litter-mates at 1, 2, 3 and 4 weeks of age. From each of 10 litters, two piglets were assigned to each of the four age groups. Piglets of all ages vocalized intensely during isolation, but call rate was lower with older piglets, especially for high-frequency calls (>500 Hz). When returned to the sow, piglets made distinctive `quacking' vocalizations, and older piglets produced fewer of these calls than younger piglets. Experiment 2 involved two treatments: weaning age and diet quality. Piglets were weaned at either 2 weeks of age and onto a diet formulated for piglets of this age, or at 4 weeks of age and fed either a diet typically provided for piglets of this age or a more palatable and nutritionally complex diet. Three piglets from each of 16 litters were assigned to each of the three treatment groups. We monitored vocalizations over the first 3 days after weaning, and measured the incidence of belly-nosing during the subsequent week. Piglets weaned onto the standard diet at 4 weeks produced high-frequency calls (>500 Hz) at a significantly higher rate than those weaned onto the more complex diet, but there was no effect of diet on the incidence of belly-nosing. Piglets weaned at 2 weeks produced more high-frequency calls and performed more belly-nosing than piglets weaned at 4 weeks onto either diet. Thus the behavioural response to separation is greater at younger ages both when the period of separation is too short for diet to be a factor (Experiment 1) and when younger piglets are provided with a specialized diet that allows them to achieve acceptable weight gain after weaning (Experiment 2). These results indicate that separation distress and frustration of suckling motivation are significant problems when piglets are weaned at less than 4 weeks of age.

Modified laying cages are being developed in a number of European countries in response to public and legal pressure for improvement of laying hen welfare. The Edinburgh Modified Cage (which has a perch, nest box, and dust bath) is one design which is practical for commercial production. The trial reported here was concerned with specifications including group size and space allowance. There were no major management problems during the year except for an outbreak of red mite which was successfully treated, and egg production was above breeders’ standards (with few downgraded eggs). Hens used the space and facilities well. For example, they showed settled nesting behavior and laid 94% of eggs in nest boxes. Their physical condition was also improved in several respects compared to control birds in conventional cages. A group size of five or fewer proved most suitable, with a space allowance of about 675 cm2/bird in the main part of the cage (915 cm2 including the nest box) for brown birds. Egg production will cost more in modified cages than in conventional cages, but less than free range.

Abstract While considerable research has been undertaken on the hormonal basis of pre-laying behaviour of domestic hens (Gallus gallus domesticus), less is known about how the behaviour is initiated and about how changes in this behaviour occur. Two experiments were conducted to investigate aspects of the interaction of pre-laying behaviour with feeding motivation. Experiment 1 examined the effect of the absence of food. Pre-laying behaviour was observed in 20 laying hens either with or without food available. The duration of pre-laying behaviour was longer when deprived of food for short or long periods of time than for hens with access to food. The time of oviposition, however, appeared unchanged suggesting that motivation for pre-laying behaviour is initially increasing and that it competes with feeding behaviour for expression when food is available. Experiment 2 examined the effect of food in the absence of deprivation. The food of 17 hens was topped up at various intervals before oviposition. Contrary to expectation the delay in oviposition was greater (24 minutes) if food was presented closer to the expected oviposition (2 minutes) than if it was earlier (12 minutes before oviposition, which caused a delay of 12 minutes). When interrupted close to oviposition, most birds repeated part of the searching phase of pre-laying behaviour (7 minutes of searching as opposed to 3 minutes). It is concluded that a hypothesis based on competition between motivational systems offers a good predictor for the start of pre-laying behaviour, but not for the duration of interruption later in the pre-laying behaviour sequence.

Because of the evidence that growth hormone gene transfer in pigs and mice can result in widespread pathological changes and more general concerns that transgenesis techniques themselves may have deleterious effects, a study was undertaken to compare the behaviour of two populations of immature female sheep, one of transgenic and one of control animals. The gene transferred was that for human alpha-1 antitrypsin factor. In the first part of the study the behaviour of 25 transgenic (T) and 25 control (C) sheep was compared in three separate situations: competition for a limited quantity of supplementary concentrate, six categories of normal behaviour on pasture and movement order when driven through a crush. With two minor exceptions (idling and ‘other’ behaviour in focally sampled animals), none of the differences observed between the two populations was significant and in most cases the mean values observed for T and C sheep were very similar. In the second part 25 T and 25 C sheep (different individuals from those in part 1) were compared in straw-littered covered pens for both normal behaviour and competition for a complete diet provided in a trough. The only significant differences in the seven categories of normal behaviour were a lower incidence of idling and ‘other’ behaviour in T sheep. There was a difference between T and C sheep in their social interaction under very competitive conditions (the T sheep reached food less quickly). The behavioural differences found in this study were all slight. Overall, the findings suggest that the gene transferred had no detectable deleterious effects on the normal behaviour of immature animals.

1. In 2 trials the health and behaviour of a total of 3552 caged laying hens of 4 hybrids, Dekalb XL, Lohmann Selected Leghorn (LSL) and Shaver 288 in trial 1 and ISA Brown and LSL in trial 2, were studied. The cage designs were Get-away cages (GA) with 15 hens per cage, a special version of the 'Edinburgh modified cage' called 'Modified and enriched cage' (ME) with 4 ISA or 5 Leghorn hens per cage, conventional metal cages with 4 hens per cage without (CO) and with a perch (PC) and conventional plastic cages (PL) with three hens per cage. GA and ME included nests, perches and sandbaths. 2. In the first trial f1p4nest models were used, artificial turf and welded wire floor. In the second trial both nest models were used in GA, while all nests in ME were equipped with artificial turf. In the second trial there were 4 sandbath treatments in ME; no sandbath, sandbath (25 x 50 cm) first opened at 16 weeks of age, sandbath first opened at 26 weeks and double size sandbath (50 x 50 cm) first opened at 16 weeks. Hens in GA were allowed access to the sandbaths from 26 weeks. 3. At 35 and 55 weeks the best plumage condition (feather cover) was found in PL and GA but plumage condition in ME was not significantly inferior than in GA. Hens in GA had the dirtiest plumage and most bumble foot but no toe pad hyperkeratosis. Some toe pad hyperkeratosis occurred in the other systems. Most keel bone lesions were found in systems with perches. The highest mortality was registered in GA. Hens in systems with perches, sandbaths and nests had increased strength of humerus at slaughter. 4. More eggs were laid in nests with artificial turf than in welded wire floor nests. LSL hens laid larger proportions of eggs in the nests (94% and 92% in the two trials) than the other hybrids. Less than 1% of the eggs in ME and 2% in GA were laid in the sandbaths. 5. The use of perches in ME and PC was approximately 30% in the day time. At night the use was 93% in ME and 89% in PC in trial 1 and 96% in ME and 81% in PC in trial 2. 6. Hens in ME with the double sized sandbath both visited the sandbath and performed dust bathing behaviour most, followed by hens in GA, hens in ME with access to the bath from 16 weeks and last, hens in ME with access to the bath from 26 weeks. 7. It is concluded that enrichments of laying cages are used by the hens to a large extent if properly constructed and managed, implying an increased behavioural repertoire of the hens compared with conventional cages. With perches at only one level and with smaller groups of birds, ME provided better hygiene and inspection properties than GA.

Persistence of searching behaviour during the pre-laying period in the presence of a suitable nest site may indicate that hens are strongly motivated to perform this behaviour. This was investigated by observing behaviour in environments with or without a suitable nest site and other cues for exploration. Eleven hens were tested individually in four environments using a 2 × 2 experimental design: presence or absence of litter and presence or absence of an exploratory walkway. Comparing pre-laying behaviour between environments with unlittered and littered nest box, longer durations of pre-laying behaviour (151(±20) vs. 110(±13) min, ANOVA, df = 1,27; P

1. Floor eggs are a problem in non-cage systems for laying hens, as they require secondary egg collecting. Failure to lay in a well-defined nest site may also be a welfare problem for the hens, but only if their nesting motivation has been thwarted. We investigated the relationships between a hen's prelaying behaviour and its tendency to lay on the floor by recording the behaviour of 20 hens housed individually in wire cages with single littered nest boxes. 3. Most floor eggs (80%) were laid by the same 6 hens. These 6 "floor-layers" performed more nest seeking behaviour, less nest-building behaviour and less sitting prior to oviposition than the 14 hens that consistently laid in nest boxes. 4. The incidence of floor eggs declined with age. Both nest and floor laying hens performed less nest seeking behaviour with age. Floor layers, however, increased their performance of nesting behaviour, whilst nest layers performed less nesting behaviour with age. 5. Floor laying hens behaved as if they found the nest box less attractive than nest-laying hens; perhaps because they had lower nesting motivation, or perhaps because their nesting motivation was as high, but they less readily perceived the nest box as an appropriate nest site.

Domestic hens (Gallus gallus domesticus) from commercial laying strains have been selected for high egg yield and may lay over 300 eggs in their working lives. In conventional wire cages, there is little opportunity to perform either nest seeking or nest building activities, which may lead to frustration each time an egg is laid. To measure the demand for a well-defined nest-site, which may act as a consummatory stimulus for nest seeking behaviour and an appetitive stimulus for nest building behaviour, 16 hens were allowed to work to gain access to a pen containing two littered, enclosed nest boxes. The cost of access to the nest boxes was varied by changing the width of the vertical gap, which divided a home pen containing food, water and a perch from the pen containing the nest boxes (gaps of 220, 140, 125, 110 and 95 mm, compared with mean body width of 117 mm). The number of entries to the nest pen declined with narrowing gap, whilst the number of failed attempts to enter rose, but all 16 hens persevered with entering the nest pen prior to oviposition and laid in the nest boxes. Between 120 and 30 min to oviposition hens made many entries with the 220 mm gap (27.6), but this declined to no entries with 95 mm gap. Hens made few entries in the last half hour prior to ovipositoin (1.3) but there was no significant decline in entries as the gap narrowed (1.1 with 95 mm gap). The number of nest inspections and nest entries also declined with width of gap, but there was no effect on time spent in the nest boxes. Hens passed gaps of 220, and 140 mm to return to the nest pen following oviposition, but did not pass gaps of 125, 110 or 95 mm. We therefore conclude that the narrow gap width can be used to assess the demand for environmental requirements. Hens were willing to pay a high cost to gain access to a nest box prior to oviposition, so prelaying behaviour may be frustrated in hens without a well-defined, littered nest site.

In two trials, production, feed consumption, mortality, egg quality and birds' live weight of a total of 2877 caged laying hens of four hybrids, Dekalb XL, Lohmann Selected Leghorn (LSL) and Shaver...

This study was designed to examine the effects of relatedness on the behaviour, especially suckling behaviour, of twin beef calves. The subjects were 20 twin calves and their 10 dams. Eight of the 10 dams were mothers of twins consisting of one calf which was conceived by artificial insemination (AI) and one calf which was induced by embryo transfer (ET). The remaining two pairs of twins were natural twins conceived by AI. Observations were made in two 10-day periods in early and late summer. Behaviour was recorded using focal-sampling procedures and suckling behaviour was recorded continuously for all calves. No significant differences were found between AI and ET calves, either for general behaviour or for suckling behaviour. The results indicate that social affinity between calves and their dams did not depend on whether the offspring was the dam's own calf or the unrelated ET calf. This is also supported by the finding that AI calves were not found in closer proximity to their mothers than ET calves. Cross-suckling was very frequently recorded in this herd of twin-nursing cows: it was involved in 42% of the nursing bouts of cows in June and in 58% of bouts in September. The duration of cross-suckling was significantly lower than the duration of suckling from calves' own mothers (P < 0.001), but cross-sucklers were more frequently observed suckling than were non-cross-sucklers (P < 0.05 and P < 0.01). Suckling from a calf's own mother almost exclusively occurred in the normal opposite parallel position, while cross-sucklers mainly sucked from alien cows from behind.

The apparent reluctance of many free-range laying hens (Gallus gallus domesticus) to disperse in the available outdoor area may be due, in part, to the large discrepancy between the indoor and outdoor environments. The objective of this study was to alter the novelty of an outdoor paddock by the introduction of familiar feeders, and examine hens' subsequent readiness to emerge from a familiar box and disperse in the area. In addition, the possible influence of social rank on emergence behaviour was examined. In Experiment 1, there were three treatments (T1, feeder inside box; T2, feeder 1 m outside box; T3, two feeders, one in either position), and hens' latencies to emerge from the box were recorded. Birds emerged earlier in T2 than in either of the other treatments. Social rank within the group did not influence emergence latency, and emergence times decreased with repeated testing. Using the same three treatments, Experiment 2 examined birds' use of four areas of the paddock. These were: 1, inside box; 2, within 1 m of box door; 3, within 30 cm of outside feeder; 4, more than 1 m from box door. Birds spent less time inside the box when there was a feeder in the paddock, but there was no treatment effect on the amount of time spent in Area 4. In Experiment 3, the positions of three feeders were altered to investigate whether dispersing feeders throughout the paddock caused birds to disperse further. Both emergence and dispersal behaviour were recorded. There were three treatments: T1, no feeders (control); T2, three feeders within 2 m of the box; T3, three feeders placed 1.5 m, 5 m and 7.5 m from the box. Compared with T1, birds emerged earlier, spent less time inside the box and more time immediately outside the box in both T2 and T3. There were no significant differences between T2 and T3, and there was no treatment effect on the amount of time spent in the area furthest from the box. Thus, birds tended to emerge earlier, and spend less time inside the box, when a feeder(s) was present in the outdoor area, but tended not to disperse further than the point of the nearest feeder.

There is some controversy as to whether animals can be deprived of resources that they have never experienced. Will domestic hens (Gallus gallus domesticus), for example, that have been housed in conventional wire cages, be as motivated to use well-defined, littered nests as hens with prior experience of nests? This was tested by varying the quality of nesting cues (trials with and without an enclosed nest box) and measuring the performance of and demand for exploratory behaviour in 16 hens with and 16 hens without prior experience of such a nest site. Each hen was tested once in a two-pen arena. The ‘home’ pen contained food, water and a perch in all trials, whereas the ‘nest’ pen had an enclosed nest box attached in only half the trials. The demand for searching behaviour was assessed by varying the width of the doorway between the two pens (widths of 160, 140, 120 and 100 mm were used, compared with a mean hen width of 122 ± 11 mm). Steps, inspections and passages between the two pens were recorded in the 3 hours prior to oviposition. All hens with the nest box laid in it, and all hens without the nest box scraped out a hollow in a corner of the arena and laid there. All hens entered the nest pen prior to oviposition and there were fewer visits with narrower gaps (38 ± 6, 22 ± 9, 12 ± 3 and 4 ± 1 visits with gaps of 160 mm, 140 mm, 120 mm and 100 mm, respectively, for hens with the nest; 133 ± 32, 107 ± 17, 73 ± 20 and 49 ± 15 for hens with no nest box; p < 0.01 for both), but no other effect on searching or nesting activities. Hens with the nest box performed less exploratory behaviour (71 ± 5 inspections and 159 ± 21 steps) and made fewer passages (20 ± 5 visits) than hens without the nest box (188 ± 18 inspections, 349 ± 44 steps and 74 ± 9 visits; all p < 0.001). There was no difference in exploratory or nesting behaviour between nest-naive and nest-experienced hens, and no difference in their response to gap width. It may therefore be possible to assess deprivation by quantifying the motivation to persevere with appetitive activities in the absence of consummatory stimuli. In this experiment demand for, and expression of, nest-seeking behaviour were independent of prior experience of nesting cues and the enclosed nest box acted as a consummatory stimulus for nest-seeking behaviour.

1. ISA Brown hens were housed as groups of 4 from 18 to 72 weeks in 24 cages 450 mm deep, each with a softwood perch of rectangular cross-section fitted across the rear. There were 4 treatments, each with 6 cages: cage widths and perch lengths were 480, 520, 560 or 600 mm. 2. Daytime perching did not differ significantly between the treatments. At night, over the whole year, 81% of birds in the 480 mm cages and 86% in the 520 mm cages roosted on the perch. This figure reached about 95% in the 560 and 600 mm cages, significantly more at most ages than in the 480 mm cages. 3. Feather damage was slightly less, but claw problems slightly more, in the 2 wider treatments than in the 2 narrower treatments. Birds in the wider cages were calmer when approached or handled by humans than those in the narrower cages. This may have been associated with variation in space allowance between the treatments. 4. There was a trend for lower production in the 480 mm cages than in the other treatments which may have been associated with the reduced feeding space in this treatment. There were few other treatment differences in production traits. 5. The balance of the evidence from this study is that when perches are provided in laying cages for medium weight hybrids, 140 mm of perch space per hen is adequate. For the amelioration of a number of the welfare problems of conventional cages, provision of perches should be combined with other modifications.

1. Laying hens (192 ISA Brown medium hybrids) were housed from 18 to 72 weeks as groups of 4 in conventional or experimental cages. The main area of all cages provided 675 cm2/hen. All experimental cages had perches, dust baths and nest boxes, which were of three types: litter (L), artificial turf (A) or plastic rollaway (P). These facilities provided an additional 375 to 480 cm2/hen. The nest boxes and dust baths occupied either high or low positions. Behaviour, physical condition and production of the birds were regularly recorded. 2. Mortality was low (1.6% overall) and egg production very good in all treatments. The proportion of cracked and dirty eggs was slightly (but not significantly) higher in the experimental cages. In the experimental cages 90% of eggs were laid overall in the nest boxes and 3% in the dust baths. The proportion laid in the nest boxes was lower early in the laying cycle and increased with time, reaching 99% in A. 3. The facilities were heavily used. Birds spent about 25% of day time on the perches and 10-15% in or near the nest box and dust bath. At night, the majority of birds (90 to 94%) roosted on perches, but most of the remainder were on the lips of the nest box or dust bath, fouling the interiors. 4. Pre-laying behaviour was much more settled in the experimental cages (45 min spent in the eventual laying position) than in the conventional ones (20 min) and total duration varied from 68 min in A to 87 min in P. The number of nest entries varied from 3.0 (A and P) to 4.3 (L); disturbance to sitting birds was correspondingly greater in L. 5. Dust bathing in the experimental cages generally took place during the afternoon in a single bout of about 5 min duration, whereas in the conventional cages it was brief and fragmented (3 bouts of 10 s each). The dust bath was also used for foraging behaviour (pecking and scratching). The treatments with small dust baths (A and P) caused problems for the birds. 6. Feather, foot and claw damage all tended to be less in the experimental than in the conventional cages, though only in the last case was the difference significant. Keel bone depressions appeared to be associated with perches; they were present in 43% of hens in the experimental cages but only 4% in conventional cages.(ABSTRACT TRUNCATED AT 400 WORDS)

1. Medium hybrid hens were housed as groups of 4 at 18 weeks of age in cages of 4 different types: control battery cages allowing 675 cm2/bird; similar cages with a rear‐mounted dust bath, 290×345×240 mm, containing sand (D); cages with a rear‐mounted nest box of the same size, containing wood shavings (N); cages with both (DN). In half the experimental cages access to nests was restricted to the morning and access to baths was restricted to the afternoon, by automatic sliding doors. 2. During the first 24 weeks of lay about 95% of eggs were laid in nest boxes in treatments N and DN. Slightly fewer were laid in boxes where doors were present. Over 90% were laid in dust baths in D cages without doors and 67% with doors, which birds learned to open. Prelaying behaviour was least disturbed in nest boxes, most disturbed on the floor and intermediate in dust baths. 3. Fully developed dust bathing occurred in D and DN as bouts lasting 5 to 10 minutes; its incidence, surprisingly, was greater when doors...

Consumption of solid food before weaning and growth before and after weaning were studied in 24 litters of eight to 13 Yorkshire × Landrace piglets per litter. From day 21 until weaning at day 28,12 litters were provided with a single two-space feeder, while the other 12 litters were provided with four similar feeders. Daily food intake by each litter was recorded throughout this period and feeding behaviour of individual piglets was filmed during the final 24 h. On the one-feeder treatment there were 4·1 (s.e. 0·6) piglets per litter which fed very little on the day before weaning (< 0·005 of sample video frames). These tended to have high birth weights and high growth rates on days 0 to 21, but low growth rates on days 28 to 42. Conversely, piglets which fed most on creep food were often those which had gained least on days 0 to 21. The four-feeder treatment increased average intake in the last 3 days before weaning and reduced the number of piglets which fed very little in the final 24 h to 0·6 (s.e. 0·3) per litter. However, neither average growth after weaning nor the occurrence of poorly performing individuals was different between treatments. Furthermore, regression analysis of factors related to weight gain from days 28 to 42 showed that feeding behaviour proportionately accounted for 0·02 only of within-litter variation and food intake on days 21 to 28 did not contribute significantly to between-Utter variation. These results suggest that low consumption of solid food before weaning is a predictor of poor growth after weaning, but not a cause.

1. ISA Brown hens were caged in groups of 4 from 20 to 72 weeks at 675 cm2/bird. A control treatment in conventional cages was compared with 4 treatments involving softwood perches. In deep cages they were located across the front, across the rear and across both; in wide, shallow cages there was one long perch across the front. For half of each treatment perches were circular in cross section, and for half they were rectangular. 2. Time spent overall in daytime perching was relatively consistent over the laying cycle, from 47% in period 1 to 41% in period 10. Perch arrangement had a major influence on perching time, which varied from 20% on the rear perch to 85% on the long perch. Predominant activities on front perches were feeding and drinking; on rear perches, preening and resting. 3. Perches were heavily used for roosting at night: the proportion varied from 60 to 72% on front or rear perches, through 72 to 78% on long perches, and 99% on two perches. 4. Physical condition was also affected ...

Effects of creep food presentation on feeding behaviour and intake were studied with eight litters of eight to 10 Yorkshire × Landrace piglets in the 3rd and 4th weeks after birth, before weaning at 4 weeks of age. In each week, four treatments were applied, each for 24 h: a single two-space feeder unchanged from the previous day; a clean feeder with fresh food supplied at 09.00 h; a clean feeder with fresh food supplied at three times during the day; and three feeders (six feeding spaces) providing increased access to food throughout the day. There were no significant differences between the first three treatments in time spent at the feeder (recorded by video over 24 h) or food intake of piglets. However, the fourth treatment increased average intake in week 3 to 2·1 times the average of the other treatments, and in week four to 1·4 times. In week 3, most piglets spent more time at the feeder when access was increased, while in week 4 the effect was restricted to piglets which ate very little. This suggested that imitative learning was important in the initiation of feeding. Analysis of both litter means and within-Utter variation showed that piglets which ate more solid food before weaning gained more weight in the 2 weeks after weaning. However, this correlation was confounded by correlations of both measures with birth weight and other variables. Causal links between creep feeding and post-weaning weight gain remain to be demonstrated.

1. ISA Brown hens were housed in groups of 4 in cages with different designs of nest boxes provided, to determine the effects of nest box design and management on their use and on the pre‐laying behaviour shown by the birds. 2. There were 5 treatments: control (C); a wire‐floored nest box attached to the back of the cage (W); a nest box containing a fibreglass rollaway hollow (N); two rollaway nest boxes (T); a rollaway nest box, protected by a partition from the main part of the cage (P). 3. The holes in the rollaway nests in treatment N, T and P were shut initially, but the proportion of eggs laid in these nests only reached 50%. This proportion rose to over 80% when wood shavings were added daily, but fell to below 30% when rollaway holes were opened. These rollaway hollows are apparently not suitable for use in laying cages. 4. Use of nest boxes in treatment W varied between 60 and 80%. However, when pre‐laying behaviour was recorded (in 19 hens) two birds which laid in the nest boxes neverth...

In a trial of cage designs for laying hens, eggs were discovered in dust baths where access was restricted by a closed door during the normal laying period (08:00–13:00 h). Observations showed that the hens in these dust bath treatments had developed methods of opening the doors in order to lay in the baths. Three different methods of opening were observed. An average time of 34.4 min was spent attempting to open the doors before access was finally achieved. This implies a strong nesting motivation in these hens. The proportion of eggs laid in the dust baths increased (with occasional fluctuations) over a 24-week period. Door opening is likely to have initially developed in one individual in each cage through a trial and error basis, and then have been learned by cage mates through imitation. The speed and efficiency of door opening was not found to increase with experience or time.

1. Behavior of ISA Brown hens was compared in cages with and without nest sites provided, to determine the characteristics necessary for such nest sites and whether part of the existing cage area could be modified to form an acceptable nest file. 2. There were 5 treatments: control (C); a wooden surround in one rear corner of the cage (S); a fiberglass rollaway hollow in one rear corner of the cage (H); a hollow and a surround (H/S); a nest box attached to the back of the cage, containing a hollow (N). 3. Use of rollaway hollows was limited, unless they were blocked and wood shavings were added, when 55 to 60% of eggs were laid in them. There were also problems with soiling of hollows. 4. When hollows were blocked, most hens used them in treatments H/S and N, suggesting that substrate and surroundings both contributed to acceptability of nest sites. 5. Pre-laying behaviour in sites within the cage was disturbed and sometimes abnormal. In addition, these sites were not used for other activities, thus limiting the space available. 6. For pre-laying behaviour to be expressed satisfactorily in cages, an additional nesting area, such as a nest box or boxes, is probably necessary.

1. A 3-year trial was carried out of cages for laying hens, occupying a full laying house. The main cage designs used were 5000 cm2 in area, 50 cm high at the rear and furnished with nests and perches. F cages had a front rollaway nest at the side, lined with artificial turf. FD cages also had a dust bath containing sand over the nest. H cages had two nest hollows at the side, one in front of the other. They were compared with conventional cages 2500 cm2 in area and 38 cm high at the rear. 2. Cages were stocked with from 4 to 8 ISA Brown hens per cage, resulting in varied allowances of area, feeder and perch per bird. No birds were beak trimmed. In F and FD cages two further treatments were applied: nests and dust baths were sometimes fitted with gates to exclude birds from dust baths in the morning and from both at night; elevated food troughs, with a lip 33 cm above the cage floor, were compared with standard troughs. 3. Management of the house was generally highly successful, with temperature control achieved by ventilation. Egg production was above breeders' standards and not significantly affected by cage design. More eggs per bird were collected when there were fewer birds per cage but food consumption also then tended to be higher. 4. The number of downgraded eggs was variable, with some tendency for more in furnished cages. Eggs laid in dust baths were often downgraded. Those laid at the back of the cage were frequently dirty because of accumulation of droppings. H nests were unsuccessful, with less than 50% of eggs laid in the nest hollows. However, up to 93% of eggs were laid in front rollaways, and few of these were downgraded. 5. Feather and foot damage were generally less in furnished than in conventional cages, greater where there were more birds per cage. With an elevated food trough there was less feather damage but more overgrowth of claws. In year 2, mortality was greater in cages with more birds. 6. Pre-laying behaviour was mostly settled in front rollaway nests. Dust baths were used more for pecking and scratching than for dust bathing. Comfort behaviour was more frequent in furnished cages than conventional, although still not frequent. Locomotion was strongly affected by number of birds per cage or by space per bird, being reduced by crowding. Most birds perched at night except in one treatment providing only 10.7 cm perch per bird. 7. Behaviour was more unrestricted and varied, and physical condition was better, in furnished than in conventional cages. However, egg production will cost more in furnished cages, partly because more eggs are downgraded. Dust baths must be fitted with gates that the birds cannot open from outside, but gates for nest boxes were found unnecessary. If a low perch is fitted it must be far enough from the back of the cage for birds to walk there. 8. Where there was less space per bird (more birds per cage) than the requirements in the 1999 European Commission Directive on laying hens, there were: fewer eggs per hen, but still above the breeders' target; lower food consumption; more feather and foot damage, but less than in conventional cages; higher mortality in one trial out of three; less freedom of movement. However, the results were still very good even with 8 birds per cage, and support the principle that furnished cages provide an acceptable way of protecting the welfare of laying hens.

1. Three experiments were carried out with ISA Brown laying hens housed in individual cages with softwood perches of rectangular cross section fitted across the width of each cage, to investigate factors affecting the tendency of hens to lay their eggs from the perches and to use perches at other times. These factors were perch width and angle and method of perch introduction. 2. In experiment 1 there were 4 treatments. Perches were 38 or 60 mm wide; half of each width were flat and half were fixed at 8 degrees, parallel to the slope of the floor. In 2 similar trials (with 48 and 44 birds respectively, equally divided between treatments) birds were moved to experimental cages already fitted with perches. Birds with 38 mm, sloping perches laid less than one third of their eggs from the perch (31% and 9% in the two trials) while those with the other designs laid more than 80% from the perch. Narrow sloping perches were not otherwise aversive and there was no consistent variation between treatments in total time perching. 3. In experiment 2, 32 birds were allowed to start laying on the floor of the experimental cages then perches were introduced at 24 weeks with 8 birds on each of 4 treatments: 50 mm perches fixed flat and 38 mm perches fixed flat, and at 5 and 10 degrees respectively. Only 27% of eggs were laid from the perches with no variation between treatments either in this behaviour or in total time perching. 4. Experiment 3 provided 24 of the birds from experiment 2 with double-length perches to determine whether they showed preferences for the design features under consideration. Either half the perch length was flat and half sloping at 10 degrees or half was 38 and half 50 mm wide. Again a relatively low proportion of eggs was laid from the perches (18%) and birds showed no significant preference for different perch designs as indicated by either how much they perched or where they perched. 5. These results suggest that both perch design and the way pullets are introduced to perches influence the proportion of perch-laid eggs. They confirm that in some circumstances laying from perches can be a serious problem, but that in other circumstances incidence can be reduced to a manageable frequency. Perches may therefore be practical in commercial production without increasing the number of cracked eggs. The results are also likely to be applicable in cages with other facilities including nest boxes.

Laying hens, Gallus gallus domesticusshow individual variation in pre-laying behaviour including their ultimate choice of nest site. In housing systems with nestboxes, the majority of hens make a small number of long visits to nestboxes and lay their eggs therein, but some hens make many short visits and occasionally lay outside the nestbox. We investigated the motivational basis of this individual variation using six consistent hens which always laid in nestboxes and six inconsistent hens which sometimes laid outside nestboxes. Each hen was housed in a pen (containing either no nestbox, a semi-enclosed nestbox or an enclosed nestbox) with access to a ring-shaped tunnel which increased the opportunity to perform locomotor activity. Access to the tunnel could be restricted by narrowing the doorway to 140, 125, 110 or 95 mm (compared with a mean hen width of 114 mm). In trials with no nestbox, there was no difference in the pre-laying behaviour of consistent and inconsistent hens. Narrowing the doorway reduced the number of visits to the tunnel, but all hens persisted in visiting the tunnel and doorwidth had no effect on time spent therein. With both designs of nestbox, however, inconsistent hens visited the tunnel more often than consistent hens prior to oviposition, and continued to pass the narrowest doors to enter the tunnel, whilst consistent hens would not pass doors of 110 or 95 mm. After oviposition, there was no difference in the two groups' behaviour in any treatment and no hens would pass doors of either 110 or 95 mm to visit the tunnel. Individual variation in nest-site choice, therefore, appeared to result from different perception of nestboxes rather than lower nesting motivation. Inconsistent hens worked as hard as consistent hens to perform pre-laying locomotion, but appeared to be less responsive to the cues provided by nestboxes than consistent hens, because they persisted with pre-laying locomotion when provided with either design of nestbox.Copyright 1997 The Association for the Study of Animal Behaviour1997The Association for the Study of Animal Behaviour

1. Behaviour, production and welfare of ISA Brown medium hybrids were assessed in 2 trials (each from 20 to 44 weeks of age) of a novel design of cage for laying hens: the Edinburgh Modified Cage (EMC). 2. The EMC was 600 mm wide, 450 mm deep and 450 mm high at the rear; it had a softwood perch and at one side a 250 mm wide nest box (containing litter or artificial turf) with a dust bath directly above. It housed 4 birds and provided 675 cm2/bird in the main cage with an additional 281 cm2/bird in the nest box. The nest box and dust bath had automatically controlled doors which were closed at night. There were 18 EMC; in the first trial these were compared with 6 control cages with perch but without next box or dust bath. 3. Hens spent 32 to 37% of day time on the perch, 5 to 7% in the dust bath and 5 to 6% in the nest. At night 92 to 98% roosted on the perch. 4. Initially only 55 to 70% of eggs were laid in the nest box partly because some eggs were laid before dawn. Once the door was retimed to open 3h before lights-on the proportion rose to 91 to 96%. Very few eggs were laid in the dust bath. Pre-laying behaviour lasted longer in treatments with nest boxes (55 to 76min) than in control cages (48min); disturbance was slight in all treatments, but lowest in control cages. 5. Dust baths were well used, with on average 61% of hens dust bathing during a 3-h afternoon observation period compared with only 17% in control cages. Two birds could use the dust bath simultaneously. 6. It was concluded that although a number of minor design features still required attention the EMC has potential to reduce the disadvantages of conventional cages for welfare while retaining their advantages and has possible commercial application.

Trabecular bone remodelling is known to be affected by loading or exercise, and thus exercise may effect the trabecular bone loss associated with osteopenia in laying hens. Sixteen ISA Brown hens were housed from 18 to 72 weeks old in cages with perches and 16 in similar cages without perches to examine the effects of the exercise afforded by perch provision on trabecular bone volume. At 72 weeks, mean trabecular bone volume in the proximal tarsometatarsus of birds with access to perches was significantly greater than in control birds, while medullary bone volume was not significantly different in the two groups. However, all the birds were considered osteoporotic, though to varying degrees, and the beneficial effects of perches were relatively minor. It was concluded that while trabecular bone loss may be reduced by perch provision, other factors are probably more influential in the development of the osteoporosis typical of laying hens.

1. ISA Brown hens were housed, from 18 to 71 weeks of age, as groups of 4 in cages with 675 cm2/bird. There were 7 treatments: control cages and 6 treatments with perches fitted across the rear of the cage. Five treatments had 450 mm wide cages, with perches made from hardwood, textured metal, smooth plastic, softwood and padded vinyl, and one treatment had a 600 mm wide cage, with a softwood perch. There were 4 cages in each of the first 6 treatments and 6 in the last. 2. Overall, birds spent about 25% of the day time on perches. Most time (28 to 41%) was spent perching on the 600 mm softwood perches. Among 450 mm perches, most time (25 to 30%) was spent on the softwood perch and least (13 to 23%) on the plastic; the results suggested that a slightly rough surface was preferred. Individual birds varied considerably in the proportion of day time they spent perching; this variation was relatively consistent over time. 3. Overall, the proportion of birds roosting on the perches at night was 85% in period 1; declined to 76% by period 6, probably because increased body size made it almost impossible for 4 birds to perch in the 450 mm cages. Birds roosting on the floor tended always to be the same individuals. 4. Damage to the soles of the feet was less in all treatments with perches than in control cages. It was least in 600 mm wide cages and showed a negative correlation with time spent perching, both within and between treatments. Long or twisted claws, in contrast, tended to be slightly worse in treatments where there was most perching. 5. Downgraded eggs tended to be slightly more frequent in cages with perches; the greatest proportion (cracked 1.4%, dirty 3.6%) was from the 600 mm wide cages, as a result of hens laying from the perch and a build-up of manure behind it. 6. Although problems remain the findings suggest that provision of perches is important for the welfare of hens; perch space should be sufficient to allow all birds to perch simultaneously.

Modifications to laying cages suggested by previous trials at Edinburgh include provision of a perch, a nest box and a dust bath, and increased area and height compared to conventional cages; the effects of combining these features is now described. Medium-weight hybrids were housed as groups of 4 in 48 cages of 4 types:control cages (C);experimental cages with nest box lined with litter (L);experimental cages with nest box lined with artificial turf (A);experimental cages with nest box lined with plastic grid (P).In sub-treatments A1 and P1, eggs were prevented from rolling away for the first 6 weeks of lay, by blocking the rollaway slot. In sub-treatments A2 and P2, eggs rolled away from the beginning of lay.

1. The effect of perching experience on use of ground level nest boxes was tested in medium hybrid hens. Twelve out of 14 hens (86%) reared without perches laid their first egg on the floor when isolated with ground level nests. Only 4 out of 19 hens (21%) reared with perches laid on the floor. Medium hybrids with experience of only one level apparently have difficulty even stepping up to another level. 2. The age at which perches should be introduced to minimise floor laying was investigated in a second experiment with medium hybrids. Five groups had perches provided at 4, 8, 12, 16 and 20 weeks respectively. Floor laying in the first group varied between 0 and 10%. The proportion of floor eggs laid by the other groups was between 31 and 100% initially, falling to between 23 and 43% by the end of the experiment. Provision of perches as early as possible is recommended. 3. In a commercial trial, perches were provided in a rearing pen of 2600 broiler grandparents. A control pen of 2130 birds had n...

The behaviour of Large White × Landrace gilts tethered in stalls was studied by scan sampling from 07.00 to 17.00 h on 3 days consecutively every 5 weeks. Results are presented on 30 gilts sampled during their first 5 weeks in the house, period 1, and on 36 gilts during the following 5-week period, period 2. Twenty individuals were common to both samples. Gilts were fed at 08.00 h with a pelleted complete diet, either on low food levels (1·25 to 2·00 kg) or on high food levels (2·2 to 4·0 kg).In both periods behaviour was strongly related to food allowance in individual gilts. Gilts on low food levels spent a greater proportion of their time in the standing position than those on high food levels (period 1, medians 0·31 and 0·12 respectively; period 2, medians 0·27 and 0·11 respectively), spent more time in repetitive behaviour (period 1, medians 0·22 and 0·04 respectively; period 2, medians 0·16 and 0·07 respectively) and spent a greater proportion of their standing time in repetitive behaviour (period 1, medians 0·46 and 0 respectively; period 2, medians 0·30 and 0 respectively). Similarly, all three measures of behaviour correlated negatively with food allowance overall, but there was some indication that food level had a threshold effect, with more activity and repetitive behaviour occurring on food levels below about 2 kg.These results suggest that if food allowances are low tether stalls are not a suitable system of housing for pregnant sows.

The involvement of light in nest-site selection by domestic fowls was tested in two strains of laying hens at two stages of maturity. Individuals that were about to lay an egg were isolated in a pen and given a choice of two sorts of nest-box, one illuminated internally and the other without illumination. Nearly all birds tested laid in one of the boxes provided, but their choice of dark or light conditions varied strongly with both strain and maturity. Only one of the four categories of hen, those of a White Leghorn strain laying their first egg, exhibited the expected preference for dark nests. Birds of a strain derived from Rhode Island Reds were more likely to lay in light nests, and with both strains hens which had previously been laying in open pens showed greater preference for light nests than did naive individuals. These results suggest that light intensity is not a fundamental factor influencing nest-site selection, but it may nevertheless haveto be considered in the management of laying hens.

1. Preferences of hens for different types of nest box were tested in two deep litter pens, each containing 300 Isabrown laying hens. Four types were offered: traditional wooden nests with litter, metal rollaway nests with plastic liners, wooden rollaway nests with artificial turf and autonests. 2. Most eggs were laid in traditional nests (70% in pen 1, 66% in pen 2). Metal rollaways were the next preferred type. These preferences were confirmed by analysis of records from individual nest boxes, and by observations of hens marked with wing tags. 3. Choice of nesting material was tested in one pen of 370 hens. Traditional nests were provided, containing either wood shavings or a mixture of buckwheat and oat husks. 4. Preferences for type of nesting material were equivocal. The majority of eggs were laid on wood shavings initially, but on buckwheat/oat husks later. Individual hens were inconsistent in their choice. A deep (100 mm) layer of nesting material was preferred to a shallow (25 mm) layer. ...

In a study of individual variation in the behaviour of tethered sows, records were made of 76 Large White × Landrace sows in their first pregnancy (gilts) tethered in stalls. Scan sampling was carried out from 07.00 to 17.00 h on 2–3 consecutive days every 5 weeks, producing sample sizes at three stages of the pregnancy (Periods 1, 2 and 3) of 48, 74 and 39, respectively. Sows were allocated to stalls at random; the influence of sows in adjacent stalls was analysed by correlation and regression analysis. Time spent standing by gilts in Period 1 correlated with that by their neighbours ( n = 48, r s = 0.35, P T ; per cent of observations) also showed an association with neighbours' behaviour: it correlated most strongly with neighbours' chain chewing and manipulation ( C ; per cent of observations) ( r s = 0.39, P F ; kg day −1 ) of −1 ( n = 16, r s = 0.67, P log e T = 5.49 ( ± 0.37 ) − 3.00 ( ± 0.25 ) log e F + 0.18 ( ± 0.06 ) log e C ( RMS = 0.868, r 2 = 50.4% It seems likely that the behaviour of neighbours was an important cause of stress of newly tethered gilts. The results have implications for the design of experiments on housing and provide further evidence that tether stalls are not a suitable system of housing for pregnant sows.

1. Medium hybrid hens were housed from 20 to 64 weeks in a deep litter house as flocks of 300, 370 and 370 and at stocking densities of 2–4 to 10–7 birds/m2 in three successive laying cycles. Sister birds were housed in cages in an adjacent building as groups of 3 and 4, at 750 or 560 cm2/bird. 2. Hen housed egg production was lower on litter (208 to 235) than in cages (230 to 253). However, the estimated 52‐week values for litter were comparable to or better than standards published by the National Farmers’ Union. 3. Ambient temperatures were well controlled in both houses, but atmospheric dust and ammonia were a problem in the litter system and ammonia was a problem in the deep pit cage house. Litter condition was good at all stocking densities. 4. There was a trend for production to increase with stocking density on litter, but to decrease in cages. 5. Most egg quality variables were similar in the two systems, although there were more dirty eggs from litter and shell thickness was slightly gr...

Operant conditioning techniques were used to measure the feeding motivation (hunger) of pigs restricted to the low food levels used under certain commercial conditions. Six Large White × Landrace boars were maintained in individual pens where they received their daily food allowance. Initially food was available ad libitum; subsequently boars were restricted proportionately to 0·8, 0·6 and 0·4 of their ad libitum intake in a Latin-square design. Finally boars were again offered their previously measured ad libitum intake (treatment 1·0). Hunger was measured by conditioning boars to press a panel 10 times to receive a 7-g reward of food. Operant response rates were measured over 20-min sessions during each of the treatments and at three times of day (pre-feeding, immediately post feeding and 5 h post feeding).Operant response rate was strongly affected by restricting food allowance (means: treatment 1·0, 42 panel presses; 0·8, 212; 0·6, 266; 0·4, 320). There was a signficant interaction between food allowance and time of day (P < 0·001). Treatments did not vary in response rate before feeding. Treatments 1·0 and 0·8 depressed response rate post feeding (P < 0·001) and treatment 1·0 also 5 h post feeding (P < 0·001). Response rates on treatments 0·6 and 0·4 did not vary significantly from one another or with time of day.Restricting pigs to low food levels resulted in a high level of hunger throughout the day. This was so even for food allowances that met current recommended feeding levels sufficient for maintenance and low weight gain (treatment 0·6 equivalent to 1·3 times maintenance). Commercial levels of feeding for the pig breeding population whilst meeting production needs do not satisfy feeding motivation. The hunger resulting from low food levels may act as a major source of stress under certain husbandry conditions such as tether and stall systems for dry sows, where sows are subject to both physical and food restriction.

Monensin increases propionic acid production in the rumen and improves the efficiency of feed conversion in fattening cattle. Trials carried out in the USA showed that 200 mg monensin/head per day was the optimum dose for increasing the rate of live-weight gain in beef cattle at pasture.Twelve pasture trials, involving a total of 434 beef cattle, were carried out during 1976 and 1977 to assess the efficacy of monensin for grazing cattle under European conditions. Each trial compared a group given 200 mg monensin/head per day in 0·5 to 10 kg of carrier supplement with a negative control group, fed blank supplement. The average initial live-weight was 260 kg and the average trial duration was 119 days. Daily live-weight gains of the control and monensin-treated cattle averaged 0·786 and 0·893 kg/head per day respectively, an advantage of 107g/head per day or 13·7 % in favour of the monensin treatment (P

1. The nesting behaviour of broiler breeders was studied in a commercial flock of nearly 4000 birds kept on deep litter by tagging a sample of 200 hens. Use of nest boxes by tagged birds was recorded on 52 d over 34 weeks. 2. Forty hens were never observed in nest boxes and 33 others were recorded only in ground‐level boxes. These 73 birds were recorded significantly less often in nest boxes and more often apparently laying on the floor than others. Fewer of them perched during observations and they started doing so later than birds which used raised nest boxes. 3. These results suggested that there were consistent floor layers, which had difficulty reaching raised nest boxes, as found previously in experimental conditions. Many or all floor layers may, however, have used ground‐level boxes sometimes. 4. Hens were inconsistent in their use of particular nest boxes, and some even nested in two distinct areas. 5. Most individuals were, however, consistent in their reaction to one or more features o...

1. Flocks of medium hybrid laying hens were housed in a modified deep litter system; the house was divided into 2, 3 and 4 pens in three successive years. Flock size was 300 or 370 and stocking density varied from 3.4 to 10.7 birds/m2. Higher densities used were above those recommended by the Ministry of Agriculture, Fisheries and Food (MAFF). 2. A random sample of 100 birds was identified with individual tags in each of the 9 flocks; regular observations using a scanning technique were made in each laying cycle to determine bird location and behaviour. 3. In all flocks the use of area by some individuals was uneven, that is, they were sighted in certain areas significantly more often than would have been expected by chance. The proportion of such individuals varied between flocks from 35 to 65%. Overall, birds spent more time on the slatted area than would have been expected from the area that it occupied. 4. A wide variety of different behaviour patterns was observed both on litter and on slats, but with foraging occurring more on litter and feeding more on slats. 5. Movement appeared to be constrained by crowding, because time spent in locomotion decreased in approximately linear fashion with increased stocking density. This provides support for MAFF recommendations of limits on stocking density in deep litter houses.

1. Normal adult laying hens, which produced 41 g egg/hen d, ate 30 g/hen d more of a pelleted diet than did hens of the same age which were induced to lay eggs internally by surgical treatment of their oviducts. This implied that 0.336 MJ metabolised energy was required to produce 0.251 MJ egg, or 75% efficiency of utilisation of ME. 2. This may not have represented the true cost of egg production because both normal and internal layers gained weight during testing, at slightly different rates, suggesting that they did not regulate energy balance precisely. 3. The internal layers were less active and also saved energy by resorbing egg material. Their greater body weight was due to unresorbed eggs and to heavier fat deposits, which were accompanied by higher concentrations of lipid in the blood. 4. It was estimated that internal layers ate 4 to 5% more per day than was required to maintain the same lipid status as normal layers; these data provide further evidence that poultry do not regulate their food intake precisely by energostatic or lipostatic means.

Proximity of individual donkeys whilst feeding was used to indicate the degree of mutual tolerance between the individuals. In animals that spend a large part or the day grazing, feeding groups may be expected to reflect the social structure of the herd. Close confinement increases proximity and may thus affect perceived social relationships. The observations were made during daylight hours on a herd of 60 donkeys. Positions of donkeys at feeders were recorded when the herd was confined to a barn and its adjacent yard in the winter. Distances between individuals were recorded when donkeys were at pasture in the summer. When donkeys were grazing at pasture, a majority were most often by themselves. However, most of these donkeys also joined feeding groups and less than half could be classified as "loners". These loners moved away from others rather than threatening them. Membership of any particular feeding group was transitory. The more stable elements of the groups were pairs of related donkeys (usually mother and offspring) and oestrous females with their attendant males. When donkeys were housed indoors, the majority fed in groups. Although there was adequate space for all donkeys to feed together, there was reduced opportunity for donkeys to feed on their own at a feeder. The majority of donkeys which had been classified as "loners" were rarely observed at the feeders. Otherwise, the social structure of the feeding groups was similar to those observed amongst grazing donkeys. The use of proximity at feeders as a measure of"sociability" in confined animals may underestimate the number of "loners" in the group. Choice of Posi t ion at a Food Trough by Dairy Cows MICHAEL C. APPLEBY and FELICITY J. MANSON Edinburgh School of Agriculture, West Mains Road, Edinburgh EH9 3JG (Gt. Britain) ABSTRACT Enforced proximity during feeding of captive animals can reduce the intake of some individuals.Enforced proximity during feeding of captive animals can reduce the intake of some individuals.

Pregnant sows tethered in individual stalls frequently show high levels of stereotypedbehaviour, such as bar biting, indicative of chronic strees. Recently the feeding regime has been implicated as a contributory factor. Sows are usually fed a restricted ration of concentrates once daily. This is consumed in 10-20 min, and it is likely that these aDirnAlS are hungry and severely frustrated in their feeding behaviour. In this experiment, the effect of hunger on the occurrence of stereotyped behaviour is examined. The behaviour of Cotswold sows was studied during their first 4 pregnancies. For 3 successive days every 5 weeks, records were made of posture and activity of individual sows and of whether activities were performed repetitively. Results are presented on 30 gilts sampled during their first 5-week period in the house. These gilts were fed low (1.25-2.0 kg) or high (2.2-4.0 kg) rations. Extensive repetitive behaviour was recorded. The most common categories were chain-chewing and chain-mAnipulation. Occurrence of this behaviour was strongly associated with rationing. Gilts on low rations stood for more time than gilts on high rations (medians 31 and 12%, respectively ), spent a greater proportion of their standing time in repetitive behaviour (medians 46 and 0%, respectively) and so spent considerably more time overall performing repetitive behaviour (medians 22 and 4%, respectively). Rationing appeared to have a threshold effect, with stereotypies being most frequent on daily rations of about 2 kg or less. Hunger is apparently a more important cause of stress in pregnant sows than was previously recognised. We suggest that if food restriction is to be practised, tether stalls are not a suitable system of housing for pregnant sows.