Public Attitudes to the Welfare of Broiler Chickens

This paper reports results from two workshops held in York, England that investigated public attitudes towards the welfare of broiler chickens. At the outset the majority of participants admitted that they knew little about how broiler chickens are reared and were shocked at some of the facts presented to them. Cognitive mapping and aspects of Q methodology were used to reveal the range of variables that participants believed affected chicken welfare, the causal relationships between those variables, and what variables were considered most and least important. While some participants focused on the importance of meeting basic needs such as access to food, water, light and ventilation, others highlighted the role of welfare regulations and public opinion. Factor analysis of the results from a ranking exercise identified two factor groups, “Factor one - The bigger picture” and “Factor two – Basic animal rights”. The findings demonstrate that some members of the public are both interested in learning about how their food is produced and concerned about the conditions faced by broiler chickens. Some are able to see clear links between public opinion and the welfare of farm animals, an important connection if consumer behaviour is to contribute towards improving animal welfare.Animal welfare, broiler chickens, cognitive mapping, public attitudes, Q methodology., Livestock Production/Industries, Consumer/Household Economics,

Preening behaviour in laying hens: Its control and association with other behaviors

Preening behaviour in laying hens has not been studied in detail, despite its association with dustbathing and possible role in feather pecking. After defining the components of the behaviour and determining the bout analysis criterion, this project examined preening behaviour and preen gland function, and how they were affected by bird age, beak treatment, and other external influences. In layer pullets studied to 19 weeks of age, preening was evident within the first few days of life, and maintained an (albeit small) part of their daily behavioural repertoire. Times spent in preening, and in all other behaviours observed except dustbathing, were affected by bird age. The only effects of beak trimming (at 8 days of age) on preening were on times spent directed at the back (in sit posture) and preen gland (in stand and sit postures), with trimmed birds showing more than non-trimmed birds. Beak trimmed birds spent less time in litter directed activity than non-trimmed birds. External influences such as frustration of feeding, feather pecking, presence of others (synchronisation), and type of floor substrate had little effect on preening, but variation in time spent preening between individuals was high. Preening observed during frustration of feeding could not be distinguished from normal preening, and so there was no evidence for classifying some preening as displacement behaviour. There were some differences in time spent preening between feather pecker and feather pecked status birds, but feather pecked birds did not preen more than non-feather pecked birds, as predicted. Groups of pen-housed layer pullets showed synchrony of preening at all ages observed, particularly when the proportion of time spent preening was high. Despite the association with dustbathing and the removal of stale feather lipids, times spent preening or dustbathing did not vary between birds housed on wire or litter floors. Peaks in preening and dustbathing were closely related in time, suggesting an association between them. Preen gland morphology and histology were affected by bird age and size, but not by floor substrate. Older birds may be experiencing preen gland congestion, as Judged by the solid consistency of preen gland contents. Feather lipid concentration was strongly affected by floor substrate when petroleum ether was used as the extractant, with some differences with bird age. Preen oil composition was affected by bird age and source of lipid (preen gland or feathers) but only 3 differences were detected with feather pecking and feather pecked status. These findings suggest that time spent preening is variable between individuals and changes with age, but is not greatly affected by the external factors tested here. Preen gland development is closely related to bird age, but the only great effect of external influences appears to be that of floor substrate on feather lipid concentration. Presumed sebaceous secretions from the skin may also influence feather lipid level, feather lipid composition, and plumage odour

Do Hens Use Enrichments Provided in Free-Range Systems?

Hens in free-range systems are given enrichments to increase foraging and limit injurious pecking, but the efficacy of enrichment types requires investigation. We studied hen behaviour and feather cover in eight commercial free-range flocks each given access to four enrichments within the shed. Sheds were split into quarters, in which two enrichments (jute ropes (R) + other) were installed. Other enrichments were: lucerne hay bales (B), pecking blocks (PB), pelleted feed (PF), or further R (control). Hens were observed at three ages, at three times per age (−1, 0, ≥1 h relative to PF application), in 1 m diameter circle locations around ropes (ControlR), Enrich (B, PB, PF, R), and Away from each enrichment. Feather scores were recorded at all ages/times, at the Away location only. Significantly more birds were in Enrich locations where PB, B, and PF were available, and least near R, ControlR, and Away locations (p p p p < 0.001) but were not consistently affected by enrichment. Enrichment replacement rates varied between farms. Enrichments costs were highest for PB and cheapest for R. Enrichments except R were used by hens, but with no obvious effect on feather cover. A balance has to be struck between enrichment benefits to hens and economics, but evidence suggested that hens did not benefit from R

Comparison of novel mechanical cervical dislocation and a modified captive bolt for on-farm killing of poultry on behavioural reflex responses and anatomical pathology

An alternative emergency method for killing poultry on-farm is required following European legislation changes (EU 1099/2009), which heavily restricts the use of manual cervical dislocation. This study investigated the kill efficacy of two mechanical methods that conform to the new legislation: (i) a novel mechanical cervical dislocation device; and (ii) a modified captive-bolt device (Rabbit Zinger™) and manual cervical dislocation (the control). Killing treatments were applied to broilers and layers at two stages of production (broilers: 2–3 and 5 weeks of age; layers: 12–13 and 58–62 weeks), with a total of 180 birds. Latency to abolition of cranial and behavioural reflexes, as well as post mortem analysis of the physiological damage produced, were used to estimate time to unconsciousness and assess kill efficacy. The novel mechanical cervical dislocation device was reliable and a practical method for killing poultry on-farm (100% kill success), with the majority of cranial reflexes showing no significant differences between interval mean durations across killing methods (eg nictitating membrane [mean = 0.7–3.3 s], and rhythmic breathing [mean = 0.0–0.3 s]), however for jaw tone and pupillary reflex, the modified Rabbit Zinger™ had significantly shorter interval mean durations compared to the control and mechanical cervical dislocation device (mean differences: jaw tone = ∼8 s; pupillary = ∼38 s). The novel mechanical cervical dislocation device resulted in consistent anatomical damage to the birds (eg high dislocation of the neck and severing of the spinal cord) compared to the manual method, despite both having 100% success rate, while the modified Rabbit Zinger™ was difficult to operate and resulted in varied anatomical damage. The novel mechanical cervical dislocation device showed promise as a replacement kill method on-farm for poultry

Welfare Risks of Repeated Application of On-Farm Killing Methods for Poultry

Council Regulation (EC) no. 1099/2009 on the protection of animals at the time of killing restricts the use of manual cervical dislocation in poultry on farms in the European Union (EU) to birds weighing up to 3 kg and 70 birds per person per day. However, few studies have examined whether repeated application of manual cervical dislocation has welfare implications and whether these are dependent on individual operator skill or susceptibility to fatigue. We investigated the effects of repeated application (100 birds at a fixed killing rate of 1 bird per 2 min) and multiple operators on two methods of killing of broilers, laying hens, and turkeys in commercial settings. We compared the efficacy and welfare impact of repeated application of cervical dislocation and a percussive killer (Cash Poultry Killer, CPK), using 12 male stockworkers on three farms (one farm per bird type). Both methods achieved over 96% kill success at the first attempt. The killing methods were equally effective for each bird type and there was no evidence of reduced performance with time and/or bird number. Both methods of killing caused a rapid loss of reflexes, indicating loss of brain function. There was more variation in reflex durations and post-mortem damage in birds killed by cervical dislocation than that found using CPK. High neck dislocation was associated with improved kill success and more rapid loss of reflexes. The CPK caused damage to multiple brain areas with little variation. Overall, the CPK was associated with faster abolition of reflexes, with fewer birds exhibiting them at all, suggestive of better welfare outcomes. However, technical difficulties with the CPK highlighted the advantages of cervical dislocation, which can be performed immediately with no equipment. At the killing rates tested, we did not find evidence to justify the current EU limit on the number of birds that one operator can kill on–farm by manual cervical dislocation

Determining the variation in premaxillary and dentary bone morphology that may underlie beak shape between two pure layer lines

ABSTRACT: Beak treatment is an effective method of reducing the damage inflicted by severe feather pecking (SFP) but there is significant pressure to eliminate these treatments and rely solely on alternative strategies. Substantial variation in beak shape exists within non-beak treated layer flocks and beak shape appears to be heritable. There is the potential to use this pre-existing variation and genetically select for hens whose beak shapes are less apt to cause damage during SFP. To do this, we must first understand the range of phenotypes that exist for both the external beak shape and the bones that provide its structure. The objective of this study was to determine the variation in premaxillary (within the top beak) and dentary (within the bottom beak) bone morphology that exists in 2 non-beak treated pure White Leghorn layer lines using geometric morphometrics to analyze radiographs. Lateral head radiographs were taken of 825 hens and the premaxillary and dentary bones were landmarked. Landmark coordinates were standardized by Procrustes superimposition and the covariation was analyzed by principal components analysis and multivariate regression using Geomorph (an R package). Three principal components (PCs) explained 85% of total premaxillary bone shape variation and showed that the shape ranged from long and narrow with pointed bone tips to short and wide with more curved tips. Two PCs explained 81% of total dentary bone shape variation. PC1 described the dentary bone length and width and PC2 explained the angle between the bone tip and its articular process. For both bones, shape was significantly associated with bone size and differed significantly between the two lines. Bone size accounted for 42% of the total shape variation for both bones. Together, the results showed a range of phenotypic variation in premaxillary and dentary bone shape, which in turn may influence beak shape. These bone phenotypes will guide further quantitative genetic and behavioral analyses that will help identify which beaks shapes cause the least damage when birds engage in SFP

On Farm Evaluation of a Novel Mechanical Cervical Dislocation Device for Poultry

Urgent development of alternative on-farm killing methods for poultry is required following the number restrictions placed on the use of traditional manual cervical dislocation by European Legislation (EU 1099/2009). Alternatives must be proven to be humane and, crucially, practical in commercial settings with multiple users. We assessed the performance and reliability of a novel mechanical cervical dislocation device (NMCD) compared to the traditional manual cervical dislocation (MCD) method. NMCD was based on a novel device consisting of a thin supportive glove and two moveable metal finger inserts designed to aid the twisting motion of cervical dislocation. We employed a 2 × 2 factorial design, with a total of eight stockworkers from broiler and layer units (four per farm) each killing 70 birds per method. A successful kill performance was defined as immediate absence of rhythmic breathing and nictitating membrane reflex; a detectable gap in the vertebrae and only one kill attempt (i.e., one stretch and twist motion). The mean stockworker kill performance was significantly higher for MCD (98.4 ± 0.5%) compared to NMCD (81.6 ± 1.8%). However, the MCD technique normally used by the stockworkers (based previous in-house training received) affected the performance of NMCD and was confounded by unit type (broilers), with the majority of broiler stockworkers trained in a non-standard technique, making adaption to the NMCD more difficult. The consistency of trauma induced by the killing methods (based on several post-mortem parameters) was higher with NMCD demonstrated by “gold standard” trauma achieved in 30.2% of birds, compared to 11.4% for MCD (e.g., dislocation higher up the cervical region of the spine i.e., between vertebrae C0–C1, ≥1 carotid arteries severed), suggesting it has the potential to improve welfare at killing. However, the results also suggest that the NMCD method requires further refinement and training optimization in order for it to be acceptable as an alternative across poultry industry, irrespective of previous MCD technique and training

Welfare assessment of novel on-farm killing methods for poultry

<p>Diagrammatic representation of the location of two drill sites either side of the sagittal suture into the skull over the forebrain (a); and placement of bi-polar electrode wires (through the two drill sites) to rest, one on each of the dorsal surfaces of the right and left telencephalon and reference electrode placed between the skin and the skull (b).</p