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Simple Summary: Light is an important environmental factor in many aspects for broiler chickens, such as behaviour and physiology, and welfare may be compromised when they are reared under low illuminance. We aimed to investigate what broiler chickens prefer when given free choice between a barn side with artificial lighting only as opposed to the other barn side with natural light through glass windows and artificial light. Environmental indicators and external conditions were monitored inside and outside the experimental barn, as well as chickens' preference regarding location in each side of the barn and their behavioural repertoire. Chickens preferred the barn side with natural and artificial light from 18 days onwards, after the heating light was removed. Chickens' behavioural repertoire changed according to barn side and their ages, expressing more natural behaviours and activity in the barn side with natural light. In summary, the birds indicated that natural light from windows makes a relevant difference in their lives, as it is what they choose when the only other option is the same in-barn environment with only artificial lighting. We aimed to investigate what broiler chickens prefer when given free choice between a barn side with artificial lighting only as opposed to the other barn side with natural light through glass windows and artificial light. Eighty-five 1 day-old male Cobb 500 broiler chickens were divided into 10 pens; half of each pen area was provided with only artificial light (OAL) and the other half with natural and artificial light (NAL), and birds were free to move across sides. Environmental indicators and external conditions such as temperature, relative humidity, air velocity, ammonia and illuminance were monitored inside and outside the barn. Chickens' preference was registered each three days, divided in categories: I (at 9, 12, and 15 days), II (at 18, 21, 24, and 27 days), and III (at 30, 33 and 36 days). The effect of the interaction between environmental indicators and week was statistically different only for illuminance. Chickens preferred NAL to OAL from 18 days onwards (II p < 0.001; III p = 0.016). Drinking (p = 0.034) and exploration or locomotion (p = 0.042) behaviours were more frequent, and "not visible" behaviours (p < 0.001) were less frequent, in NAL. Foraging was the only behaviour with an interaction effect between age category and light treatment, as birds during period II expressed this behaviour more frequently in NAL than OAL (p = 0.003). For our experimental conditions, the chickens preferred NAL from 18 days of age onwards, when the confounding effect of the heating light was removed, and their behavioural repertoire was also different according to each side of the barn and to their ages. [ABSTRACT FROM AUTHOR]

Abstract: A prototype lying mat as an alternative to straw bedding for improving sow lying comfort was evaluated using a dynamic group of 47 gestating sows housed in a pen with 5 communal lying areas. Mats were installed in 3 lying areas while the concrete floors of the remaining lying areas remained uncovered (period 1). After 5 weeks the position of the lying mats was rotated (period 2). 24h image-recordings were made from 5 weeks prior to the installation of the mats (period 0) until 5 weeks after rotation of the mats. The effect of the mats on lying area occupancy and behaviour was analysed. The occupancy of lying areas with a mat increased as compared to both the same lying areas before the installation of the mats (period 0), and to the other lying areas without a mat during the same observation period (periods 1 and 2, P =0.011). This preference was more pronounced amongst sows that had been habituated to the experimental set-up for more than 7 days (P <0.001) and in period 2 than period 1 (P =0.004). However, the effects of period, stocking density and ambient temperature were confounded and could not be determined unambiguously. Mats did not significantly affect activity (proportion of time standing, sitting, and lying), lying bout duration, duration of lying per lying posture (sternal, half recumbent, recumbent) or getting-up duration. Sows lying on mats as compared to concrete, however, changed lying posture more often (P =0.002) and were more likely to adopt a recumbent instead of sternal lying posture (P =0.003). Under conditions of this experiment covering concrete floors with synthetic mats appeared to improve sow lying comfort. It is questionable whether this finding can be generalised to other (climatic) conditions. Furthermore, before such mats should be considered as an alternative to straw bedding for improving lying comfort further research is warranted to improve the durability of the mats and to investigate the long-term health consequences. [Copyright &y& Elsevier]

Abstract: The provision of straw in animal production systems is widely presumed to be beneficial for the welfare of the animals. The aim of this paper is to review the scientific basis of this assumption for pigs and cattle. As there are important disadvantages (cost, labour, hygiene and incompatibility with manure drainage systems) associated with the use of straw, studies investigating whether there are suitable alternatives to straw that fulfil the same welfare functions are also reviewed. It is concluded that straw has many positive effects on the welfare of pigs. Bedding improves the physical comfort of the floor, and—unless temperatures are high—straw enables pigs to somewhat control their microclimate thereby increasing thermal comfort. Straw also functions as an important stimulus and outlet for exploration, foraging, rooting and chewing behaviours. Pigs that are feed restricted or housed in barren environments, in particular, can be strongly motivated to express these behaviours and the inability to do so may result in behavioural problems or anomalies. In addition, it has been demonstrated that preparturient sows are highly motivated to obtain nesting material and that straw can have a beneficial effect on maternal behaviour after farrowing. Although there may be superior alternatives for each of these functions of straw separately, it remains unlikely that these alternatives can adequately replace the total combination of these functions and also offer advantages regarding hygiene, environment, labour and economics. The importance of straw for the welfare of cattle mainly concerns floor-comfort. However, it appears that the provisioning of (high quality) synthetic lying mats, perhaps in combination with soft walking floors, may provide floor-comfort equal to that of straw. Although the consumption of straw reduces feeding motivation, and hence, the development of oral stereotypies, the behavioural function of straw is less for cattle compared to pigs. Moreover, it is possible to compose more appropriate roughage-feeds that better fulfil the behavioural as well as the dietary needs of cattle. For both pigs and cattle, there is weak evidence that concrete flooring rather than straw is a risk factor for increased overall morbidity and mortality. However, the relation between straw and health is complex, equivocal and disease specific. [Copyright &y& Elsevier]

Group housing is often assumed to improve the welfare of gregarious species. Whether this is actually the case depends on the advantages (e.g. more opportunity for social and locomotor behaviour) and disadvantages (e.g. increased fighting and wounding) induced by the specific housing type. We evaluated the effects of a semi-group system (grouping four does for half of each reproductive cycle) on welfare by comparing it to single-doe cages. Compared to this control, our semi-group system provided more total space when does were grouped and more space per doe (a confounding deemed necessary to avoid overt aggression). Thus, the results should be interpreted as a systems comparison. In each of the four experimental cycles semi-group does were housed separately for 21 days around parturition and housed in newly assembled groups for the next 21 days. Behaviour was observed in semi-group and single-doe systems immediately after the second time semi-group does were mixed, and during five timeslots divided over the second experimental cycle. Skin lesion and weight loss were determined in each cycle. Adrenal weight was measured post-mortem. Semi-group systems with different floor types were included but floor type effects were scarce and semi-group systems were therefore treated as one category. In the timeslot subsequent to mixing semi-group does spent a greater percentage of their time on locomotion (4.3 vs. 0.7%, P < 0.01) and social sniffing/grooming (1.4 vs. 0%, P < 0.01) than does in single-doe cages. Such differences also occurred in later timeslots, but were much smaller (e.g. midnight locomotion D12: 0.8 vs. 0.2%, P < 0.05, midnight social sniffing/grooming D12: 0.4 vs. 0%, P < 0.01). Attacking/chasing followed a similar pattern (following mixing: semi-group 5.3% vs. single 0%, P < 0.01; midnight D12: 0.01 vs. 0%, P < 0.10). A high percentage of semi-group does were slightly (58%) or severely (20%) wounded. Semi-group does spent a smaller percentage of the timeslot following mixing in bodily contact with adults than does from single-doe housing (who could only make contact through the wire walls, 1.6 vs. 11.8%, P < 0.01). Even 12 days after mixing the percentage of time semi-groups spent in bodily contact did not exceed that in singles ( P > 0.10). In experimental cycle one only, semi-group does lost more weight during late lactation than singles (192 vs. 10 g, P < 0.01). Adrenal weights did not differ between systems ( P > 0.10). Further research will be needed to design semi-group systems with a more favourable balance between advantages and disadvantages. [ABSTRACT FROM AUTHOR]

Abstract: Broiler chickens are reported to be close to walls at higher densities. The reason for this is not clear, since evolutionary theories would suggest that birds should attempt to be in the middle of the flock. We studied the spatial distribution (during weeks 4–6) of broiler chickens stocked at 2.4, 5.8, 8.8, 12.1, 13.6, 15.5, 18.5 and 21.8birds/m2 (in 3.3m2 pens), to investigate the underlying reasons for the pattern of spatial distribution. Three possible reasons were considered: seeking cover from predators in the centre of the flock, seeking cover from predators near walls, and avoidance of disturbances by conspecifics. Spatial distribution was analysed by comparing the number of birds in four separate parts of the pen (inner, inner middle, outer middle and outer). Apart from effects on spatial distribution, birds were predicted to have their behaviour disturbed more often by other birds in the flock as the overall density in the pen increased, leading to shortened bouts of behaviour and an increase in adjustments of the sitting or lying posture. We found that higher treatment density led to shorter sitting and preening bouts (P =0.024 and P =0.013), and a sharper decrease in walking bout length as weeks progressed (density×week, P =0.025). In addition, birds adjusted their sitting or lying posture more often at higher densities (P <0.001), indicating an increased number of disturbances. Preference for the wall area occurred when overall density in the pen peaked (in the last week of rearing, at treatment densities above 12.1birds/m2). On the other hand, more animals were present in the centre of the pen than at the edges at some of the densities in weeks 4 and 5. Because of its occurrence at peak density, avoidance of disturbance seems the most likely explanation for wall preference. Thus, increased use of the wall area may be an indicator that birds are experiencing crowding. [Copyright &y& Elsevier]