Pharmacological validation of an attention bias test for conventional broiler chickens

Fear and anxiety are considered concerns for animal welfare as they are associated with negative affective states. This study aimed to pharmacologically validate an attention bias test (ABT) for broiler chickens (Gallus gallus domesticus) as a cognitive bias test to determine anxiety. Two-hundred-and-four male Ross 708 broiler chickens were arbitrarily allocated to either the anxiogenic or control treatment at 25 days of age (n = 102/treatment). Birds from the anxiogenic group were administered with 2.5 mg of β-CCM (β-carboline-3-carboxylic acid-N-methylamide [FG 7142]) per kg of body weight through an intraperitoneal injection (0.1 ml/100 g of body weight). Birds from the control group were administered with 9 mg of a saline solution per kg of body weight. During ABT, birds were tested in groups of three (n = 34 groups of three birds/treatment) with commercial feed and mealworms as positive stimuli and a conspecific alarm call as a negative stimulus. Control birds were 45 s faster to begin feeding than anxiogenic birds. Birds from the control group vocalized 40 s later and stepped 57 s later than birds from the anxiogenic group. The occurrence of vigilance behaviors did not differ between treatments. This study was successful in pharmacologically validating an attention bias test for fast-growing broiler chickens, testing three birds simultaneously. Our findings showed that latencies to begin feeding, first vocalization, and first step were valid measures to quantify anxiety.

Estimates of Current Capacity for Diagnosing Alzheimer's Disease in Sweden and the Need to Expand Specialist Numbers

BACKGROUND

The emergence of disease-modifying Alzheimer's (AD) treatments provides new hope to patients and families but concerns have been raised about the preparedness of healthcare systems to provide timely access to such treatments because of a combination of a complex diagnostic process and a large prevalent pool.

OBJECTIVES

We assess the preparedness of Sweden, a high-income country known for its dementia-friendly policies, to diagnose AD patients eligible for treatment within a six-month window, given current capacity for specialist evaluations and biomarker testing. We calculate the investment requirements for Sweden to achieve this target over a timeframe of 20 years.

DESIGN

Desk research to identify data for population, mortality, disease burden, cost of services and current capacity, expert consultation to inform assumptions about patient journey, and use of a Markov model to predict waiting times. The model simulates the patients' journey through different evaluation stages: initial evaluation by a primary care specialist, neurocognitive testing by an AD specialist, and confirmatory biomarker testing with PET scanning or cerebrospinal fluid (CSF) testing. The model assumes specialist appointments and PET scans are capacity constrained, and patients progress from cognitively normal to MCI and from MCI to dementia in the resulting waiting times.

MEASUREMENTS

Projected waiting times for diagnosis of eligibility for disease-modifying Alzheimer's treatment from 2023 to 2042 assuming current capacity, assuming 20% of Swedish residents aged 60 years and above would seek an evaluation for cognitive decline. Investments required to scale capacity up to reach target of providing diagnosis within six months on average.

RESULTS

Initial average waiting times for AD specialist appointments would be around 21 months in 2023 and remain around 55 months through 2042, as demand would continue to outstrip supply throughout the 20-year model horizon. Waiting times for biomarker testing would be stable at less than four weeks, as patients would be held up in the queue for their first specialist consultations, and use of CSF testing is widely accepted in Sweden. An additional 25% of AD specialists would have to be added above the current growth trend to reduce waiting times to less than 6 months at an average annual cost of approximately 805 million SEK. The increased cost of volume of biomarker testing would amount to about 106 million SEK per year.

CONCLUSIONS

At current capacity, the Swedish healthcare system is unable to provide timely diagnosis of patients eligible for disease-modifying AD treatment. Although future diagnostic technologies, such as digital cognitive assessments and blood tests for the AD pathology, might decrease demand for capacity-constrained services, substantial investments will be required to meet a target of less than six months of waiting time for a diagnosis.

Public and industry knowledge and perceptions of US swine industry castration practices

In the United States (US), surgical castration of male piglets is typically performed without any form of analgesia. This may raise concerns with the public; however, there is no information regarding current public knowledge on swine industry practices in the US. In this study we gained insight into public knowledge and perception on castration with and without analgesia in comparison to knowledge of industry stakeholders on these same topics. Through an online survey, 119 respondents were asked four questions about castration in the US swine industry. Industry respondents were contacted via social media and networking. The general public sample was accessed through Mechanical Turk. Survey responses were categorised by experience (industry vs public). Industry respondents were more aware of practices compared to the general public. Most public respondents were unaware of castration practices and the lack of analgesia use. Respondents from rural communities were more aware of castration practices than (sub)urban communities and more aware of analgesia use than those from urban communities. Those with more education had greater awareness of castration practices (occurrence not frequency). Based on the results from this first US sample, knowledge on industry practices was especially lacking for public respondents, but also for a minority of industry respondents, indicating opportunities for education and further research on the topic.

Patterns of Independence in Adolescent/Young Adult (AYA) Survivors of Childhood Cancer Having Received Radiotherapy (RT)

PURPOSE/OBJECTIVE(S)

AYA cancer survivors are at risk for missed care opportunities due to transitions of care and movement towards independence. This study was undertaken to evaluate steps towards independence of AYA survivors voluntarily using a free, Internet-based tool for creation of survivorship care plans (SCP).

MATERIALS/METHODS

A free, publicly accessible tool, Smart-ALACC (Smart Adult Living after Childhood Cancer) was made available on Oncolink.org. Analysis of convenience sample frame was performed with IRB approval.

RESULTS

From 12/2017-12/2022, 676 AYA survivors utilized the tool; 55% (372) identified as female. Most (75%, 506) were white, 7% (48) Black, 7% (46) Asian, 6% (42) Hispanic, 5% other/ mixed race. Median age was 20y (R <16 - 46y) and median age at diagnosis was 11 y (R <1y - 21). Most common diagnoses were leukemia (31%, 212), lymphoma (21%, 140), sarcoma (14%, 95), CNS (9%, 54), and neuroblastoma (5%, 37). 311 pts (46%) reported having had RT, most commonly brain (PB) (19%, 60), "mantle" (14%, 43), craniospinal (CSI) (12%, 36), total body irradiation (TBI) (11%, 34), and head/ neck (8%, 26). Most (92%, 619) denied recurrence /secondary malignancy. Users reported being students (64%, 434) or working (24% (163)) full-time (20%) or part-time (4%); 4% (25) were neither. Most reported living with parents (71%, 482), 14% (92) with a partner/ spouse, 7% (46) alone, and 4% (30) with a roommate. Most reported using parental insurance (54%, 368), while 24% (163) had their own private insurance, 7% (49) public, and 2% uninsured. Of 466 users 18+ (466), more were employed (34%, 155, p = 0.04), living separately from parents (40%, 168, p < 0.001), and had independent insurance (52%, 184, p = 0.03). Of users 23+ (244), 141 (57%) were being employed (p < 0.001), 83% (153) living separately from parents (p < 0.001), and 165 (67%) had independent insurance (p < 0.001). Among users age 23+, survivors who had received brain RT (CSI, brain, or TBI) were less likely to live separately parents or with a spouse/ partner (p < 0.001), but equally likely to be employed (Table 1).

CONCLUSION

AYA survivors choosing to use a SCP tool have diagnoses reflective of diagnostic patterns in pediatric oncology; many have had RT expected to be associated with cognitive and developmental late effects. Despite this, trends towards employment and independence were evident in young adult population compared to adolescent; somewhat less so in survivors having had brain RT. These data suggest that AYA survivors display independence from parents and require population directed survivorship support; future efforts should aim to include a more diverse body of users.

Influence of Perch-Provision Timing on Anxiety and Fearfulness in Laying Hens

Perches can enhance laying hen welfare, but their effectiveness might be age-dependent. We investigated early and late perch access effects on anxiety and fear in pullets through attention bias (AB) and tonic immobility (TI) tests. Pullets (n = 728) were raised with or without multi-level perches: CP (continuous perch access: 0-37 weeks), EP (early perch access: 0-17 weeks), LP (late perch access: 17-37 weeks), and NP (no perch access). AB was conducted in weeks 21 and 37 (n = 84/week), and TI was performed in weeks 20, 25, and 37 (n = 112/week). CP hens fed quicker than EP, LP, and NP in AB at weeks 21 and 37 (p ≤ 0.05). CP and NP feeding latencies were stable, while EP and LP fed faster at week 37 (p ≤ 0.05). CP had the shortest TI at week 20 (p < 0.05). CP and LP had the shortest TI in weeks 25 and 37 (all p ≤ 0.05). Unlike NP, CP reduced anxiety and fear. Adding perches during laying (LP) raised anxiety at week 21, adapting by week 37, and removing pre-laying perches (EP) worsened fear at weeks 20 and 25 and anxiety at week 21, recovering by week 37. Adding or removing perches prior to the lay phase increased fear and anxiety, an effect that disappeared by week 37 of age. Our study indicates that continuous perch access benefits animal welfare compared to no perch access at all.

Environmental Complexity and Reduced Stocking Density Promote Positive Behavioral Outcomes in Broiler Chickens

The objective was to evaluate the impacts of a complex environment and stocking density on Ross 708 broiler chicken behaviors. Eight pens contained either high complexity (HC) or low complexity (LC) environments, and high (HD) or low (LD) density. Through focal-animal sampling, the frequency and duration of behaviors were recorded continuously for 5 min at two timepoints for one day in weeks 2, 4, and 7. Birds were active for 30% of the observed time, with birds showing more activity in HC compared with LC. Birds in HC pens spent more time preening and foraging than birds in LC pens, which was interpreted as a positive outcome. Dustbathing and play were not impacted by complexity, possibly due to the observation method. Birds were more frequently active at HD compared with LD, but did not spend more time being active, suggesting disturbances. Birds foraged, drank, and ate less frequently in HD compared with LD, presumably because birds had more difficulty accessing resources. Activity and active behaviors reduced as birds aged, while preening frequency increased, possibly due to frustration, but this was not confirmed. Perching was unaffected by age, showing a persistent motivation to perform the behavior. Our results indicate that a complex environment provides positive stimulation for foraging, locomotion, preening, and overall activity. Despite reduced activity, many benefits of the tested environmental complexity and low density persisted as birds aged.

Measuring Chronic Stress in Broiler Chickens: Effects of Environmental Complexity and Stocking Density on Immunoglobulin-A Levels

Commercial housing conditions may contribute to chronic negative stress in broiler chickens, reducing their animal welfare. The objective of this study was to determine how secretory (fecal) and plasma immunoglobulin-A (IgA) levels in fast-growing broilers respond to positive and negative housing conditions. In three replicated experiments, male Ross 708 broilers (n = 1650/experiment) were housed in a 2 × 2 factorial study of high or low environmental complexity and high or low stocking density. In experiments 1 and 3 but not in experiment 2, high complexity tended to positively impact day 48 plasma IgA concentrations. When three experiments were combined, high complexity positively impacted day 48 plasma IgA concentrations. Stocking density and the complexity × density interaction did not impact day 48 plasma IgA concentrations. Environmental complexity and the complexity × density interaction did not impact day 48 secretory IgA concentrations. A high stocking density negatively impacted day 48 secretory IgA concentrations overall but not in individual experiments. These results suggest that environmental complexity decreased chronic stress, while a high stocking density increased chronic stress. Thus, plasma IgA levels increased under high-complexity housing conditions (at day 48), and secretory IgA levels (at day 48) decreased under high-density conditions, suggesting that chronic stress differed among treatments. Therefore, these measures may be useful for quantifying chronic stress but only if the statistical power is high. Future research should replicate these findings under similar and different housing conditions to confirm the suitability of IgA as a measure of chronic stress in broiler chickens.

Social-pair judgment bias testing in slow-growing broiler chickens raised in low- or high-complexity environments

Impacts of environmental complexity on affective states in slow-growing broiler chickens (Gallus gallus domesticus) are unknown. Chickens' performance in judgment bias tests (JBT) can be limited as they are tested individually, causing fear and anxiety. The objectives were to apply a social-pair JBT to assess the effect of environmental complexity on slow-growing broiler chickens` affective states, and assess the impact of fearfulness, anxiety, and chronic stress on JBT performance. Six-hundred Hubbard Redbro broilers were housed in six low-complexity (similar to commercial) or six high-complexity (permanent and temporary enrichments) pens. Twelve chicken pairs were trained (1 pair/pen, n = 24 chickens) using a multimodal approach (visual and spatial cues), with reward and neutral cues of opposing color and location. Three ambiguous cues were tested: near-positive, middle, and near-neutral cues. Approach and pecking behavior were recorded. Eighty-three percent of chickens (20/24) were successfully trained in 13 days. Fearfulness, anxiety, and chronic stress did not impact chickens' performance. Chickens successfully discriminated between cues. Low-complexity chickens approached the middle cue faster than high-complexity chickens, indicating that they were in a more positive affective state. The environmental complexity provided in this study did not improve affective states in slow-growing broiler chickens compared to a control. A social-pair JBT resulted in excellent learning and testing outcomes in slow-growing broilers.

Effect of silvopasture system on fearfulness and leg health in fast-growing broiler chickens

A silvopasture system intentionally integrates trees, forages, and livestock, allowing dual land use. These systems can provide high-quality habitat for broiler chickens; however, such systems have not been widely adopted by the broiler industry in the United States. The objective of this study was to examine the effect of silvopasture versus open pasture access on fearfulness and leg health in fast-growing broiler chickens. A total of 886 mixed-sex Ross 708 chicks in Experiment 1 (Exp 1) and 648 chicks in Experiment 2 (Exp 2) were housed in coops and had access to 16 (Exp 1) or 12 (Exp 2) 125m2 silvopasture plots (x̄ = 32% canopy cover) or open pasture plots (no canopy cover) from day 24 of age. Fearfulness was measured using a tonic immobility test (tonic immobility duration), and leg health was assessed by quantifying footpad dermatitis, hock burns, gait, and performing a latency-to-lie test on days 37-39 of age. Birds in the silvopasture treatment were less fearful than birds in the open pasture treatment. Overall, birds in both silvopasture and open pasture systems had excellent leg health. Silvopasture birds had lower footpad dermatitis scores than open pasture birds. Silvopasture birds tended to have worse gait than open pasture birds in Exp 1, but not in Exp 2. Hock burn scores and latency-to-lie did not differ between treatments in Exp 1 or Exp 2. Raising birds in silvopasture reduced fear and improved footpad health compared to birds raised in open pastures, which indicates that silvopasture systems provide some benefits for affective state and leg health in fast-growing broilers.

Providing environmental enrichments can reduce subclinical spondylolisthesis prevalence without affecting performance in broiler chickens

Environmental enrichment can increase the occurrence of natural behavior and improve leg health and other animal welfare outcomes in broiler chickens. This study aimed to assess the effects of three environmental enrichments, specifically hay bales, step platforms, and laser lights, on subclinical spondylolisthesis prevalence, productivity, behavior, and gait of broiler chickens (Gallus gallus domesticus). Twenty-four hundred day-old male Ross® AP95 chicks from a commercial hatchery were used in a completely randomized design with four treatments and four replicate pens per treatment. Pens contained either a Control (C) treatment, an environment similar to a commercial broiler chicken system without environmental enrichments, or an environment with either additional hay bales (HB), additional step platforms (SP), or additional laser lights (LL). Performance, yield, behavior (frequencies), gait score, and subclinical spondylolisthesis prevalences were assessed. When raised with SP or LL access, fewer chickens had subclinical spondylolisthesis than chickens without enrichments (C) or with HB access. Chickens with access to SP exhibited higher wing yield and less abdominal fat than animals from the C group. Chickens from the LL and HB treatments explored more and rested less frequently than animals from the C and SP treatments. As chickens aged, they became less active, exploring less and increasing resting and comfort behaviors. Treatments did not affect gait. Gait was not associated with subclinical spondylolisthesis prevalence. Environmental enrichments benefitted chicken health (subclinical spondylolisthesis) and behavior (exploration) without negative consequences for performance and yield.

Enhancing their quality of life: environmental enrichment for poultry

Providing environmental enrichments that increase environmental complexity can benefit poultry welfare. This Poultry Science Association symposium paper is structured around four themes on 1) poultry preferences and affective states 2) species-specific behavior, including play behavior and the relationship between behavior, activity level and walking ability, 3) environmental enrichment and its relationship with indicators of welfare, and 4) a case study focusing on the application of enrichments in commercial broiler chicken production. For effective enrichment strategies, the birds' perspective matters most, and we need to consider individual variation, social dynamics, and previous experience when assessing these strategies. Play behavior can be a valuable indicator of positive affect, and while we do not yet know how much play would be optimal, absence of play suggests a welfare deficit. Activity levels and behavior can be improved by environmental modifications and prior research has shown that the activity level of broilers can be increased, at least temporarily, by increasing the environmental complexity. However, more research on impacts of enrichments on birds' resilience, on birds in commercial conditions, and on slow(er)-growing strains is needed. Finally, incorporating farmers' expertise can greatly benefit enrichment design and implementation on commercial farms.

Seeing is caring – automated assessment of resource use of broilers with computer vision techniques

Routine monitoring of broiler chickens provides insights in the welfare status of a flock, helps to guarantee minimum defined levels of animal welfare and assists farmers in taking remedial measures at an early stage. Computer vision techniques offer exciting potential for routine and automated assessment of broiler welfare, providing an objective and biosecure alternative to the current more subjective and time-consuming methods. However, the current state-of-the-art computer vision solutions for assessing broiler welfare are not sufficient to allow the transition to fully automated monitoring in a commercial environment. Therefore, the aim of this study was to investigate the potential of computer vision algorithms for detection and resource use monitoring of broilers housed in both experimental and commercial settings, while also assessing the potential for scalability and resource-efficient implementation of such solutions. This study used a combination of detection and resource use monitoring methods, where broilers were first detected using Mask R-CNN and were then assigned to a specific resource zone using zone-based classifiers. Three detection models were proposed using different annotation datasets: model A with annotated broilers from a research facility, model B with annotated broilers from a commercial farm, and model A+B where annotations from both environments were combined. The algorithms developed for individual broiler detection performed well for both the research facility (model A, F1 score &gt; 0.99) and commercial farm (model A+B, F1 score &gt; 0.83) test data with an intersection over union of 0.75. The subsequent monitoring of resource use at the commercial farm using model A+B for broiler detection, also performed very well for the feeders, bale and perch (F1 score &gt; 0.93), but not for the drinkers (F1 score = 0.28), which was likely caused by our evaluation method. Thus, the algorithms used in this study are a first step to measure resource use automatically in commercial application and allow detection of a large number of individual animals in a non-invasive manner. From location data of every frame, resource use can be calculated. Ultimately, the broiler detection and resource use monitoring might further be used to assess broiler welfare.

Recognizing Post-Castration Pain in Piglets: A Survey of Swine Industry Stakeholders and the General Public

We need validated, practical methods for pain assessment in piglets. Pain assessment can help researchers, veterinarians and industry professionals identify the need for analgesia or other pain management approaches when applying painful procedures, such as surgical castration. A pain assessment tool, the Piglet Grimace Scale (PGS), was previously validated in this context, but it is not widely applied. It is important that the PGS can be applied by a range of people, not just pain assessment experts. Our objective was to study the validity and reliability of PGS ratings applied by swine industry professionals and the general public, to assess its potential utility in non-research applications. To do so, we conducted an online Qualtrics survey in which, after completing a brief online training module and a practice test, 119 respondents were asked to rate 9 piglet images showing facial expressions immediately after surgical castration or sham-handling. Respondents were provided information on the castration treatment for each image and had continuous access to the scale throughout the survey. The survey also contained demographic questions. Industry respondents were recruited through networking, and participants from the general public were recruited through Amazon Mechanical Turk. Four trained experts scored each image, and these scores were averaged to produce gold standard scores. Intraclass correlations indicated strong internal consistency among experts, industry and public. ANOVA demonstrated scoring to be moderately comparable between groups. Campbell and Fiske’s Multi-Trait Multi-Method framework provided qualified support for the internal validity and reliability of the PGS scale, even applied by non-experts (industry and public). Both response groups were able to recognize pain in castrated piglets. However, public respondents attributed higher levels of pain to sham-handled piglets than industry respondents (2.83 vs. 2.35; p=0.047), and both response groups systematically overestimated pain experience compared to the experts, suggesting more training may be necessary before using the scale in a diagnostic capacity. Nevertheless, overall findings support wide applicability of PGS, even with minimal training, to improve awareness, recognition and monitoring of swine pain among veterinarians, industry professionals and even members of the public.

Effects of Housing System on Anxiety, Chronic Stress, Fear, and Immune Function in Bovan Brown Laying Hens

The scientific community needs objective measures to appropriately assess animal welfare. The study objective was to assess the impact of housing system on novel physiological and behavioral measurements of animal welfare for laying hens, including secretory and plasma Immunoglobulin (IgA; immune function), feather corticosterone (chronic stress), and attention bias testing (ABT; anxiety), in addition to the well-validated tonic immobility test (TI; fearfulness). To test this, 184 Bovan brown hens were housed in 28 conventional cages (3 birds/cage) and 4 enriched pens (25 birds/pen). Feces, blood, and feathers were collected 4 times between week 22 and 43 to quantify secretory and plasma IgA and feather corticosterone concentrations. TI tests and ABT were performed once. Hens that were from cages tended to show longer TI, had increased feather corticosterone, and decreased secretory IgA at 22 weeks of age. The caged hens fed quicker, and more hens fed during the ABT compared to the penned hens. Hens that were in conventional cages showed somewhat poorer welfare outcomes than the hens in enriched pens, as indicated by increased chronic stress, decreased immune function at 22 weeks of age but no other ages, somewhat increased fear, but reduced anxiety. Overall, these novel markers show some appropriate contrast between housing treatments and may be useful in an animal welfare assessment context for laying hens. More research is needed to confirm these findings.

Evaluation of mechanical cervical dislocation, captive bolt, carbon dioxide, and electrical methods for individual on-farm euthanasia of broiler breeders

Efficacious euthanasia by applying manual cervical dislocation can be difficult on large and mature poultry. The challenge with using manual cervical dislocation is that the strength required to hold heavy poultry and swiftly apply cervical dislocation can be physically impossible for most people. Therefore, alternative methods of euthanasia are needed for mature and large poultry. Mechanical cervical dislocation using the Koechner Euthanizing Device (KED), captive bolt using the Turkey Euthanasia Device (TED), carbon dioxide (CO₂), and electrical euthanasia were evaluated for use on 65-wk-old broiler breeders at flock termination. Following application of each method, physiological reflexes including the eye nictitating membrane reflex, mouth gaping, and body movement, broken skin, blood loss, kill success, time to cessation of heartbeat, and blood plasma corticosterone levels were assessed. Birds euthanized using the KED had longer response durations for eye nictitating membrane (91 s) and reflexive mouth gaping (161 s) compared to TED, CO₂, and electrical euthanasia (0–7 s). Body movement durations were also longer for KED (214 s) and TED (209 s) than for CO₂ and electrical euthanasia (0–8 s). The highest percentages of broken skin (93%) and blood loss (96%) were observed for TED, followed by KED (71%, 68%), then CO₂ (0%, 6%) and electrical euthanasia (0%, 3%). No significant differences (P = 0.1781) were observed for kill success rates with 98% for KED, 100% for TED, 97% for CO₂, and 100% for electrical euthanasia at 4-min. Time to heartbeat cessation did not differ between KED (659 s), TED (427 s), or CO₂ (583 s) euthanasia methods. No heartbeat was detected following electrical euthanasia. Blood plasma corticosterone levels did not differ between preeuthanasia or posteuthanasia from any of the methods applied. Based on these results each euthanasia method is acceptable for use with broiler breeders.

Comparison of Methods for Individual Killing of Broiler Chickens: A Matter of Animal Welfare and On-Farm Feasibility

The humane killing of individual broiler chickens on-farm requires a minimum of suffering. In this regard, rapid and irreversible loss of consciousness are important determinants. This can be verified by cerebral and spinal reflexes. Also, on-farm feasibility determines whether producers will apply the method. The aim of the study was to compare the effectiveness and animal welfare impact of two different methods for killing individual broilers of varying ages (2, 4, and 6 weeks): manual cervical dislocation (CD) and captive bolt (CB). The evaluation of CD and CB was based on effectiveness and on time to onset (convulsions) or cessation (pain response, pupillary light reflex, convulsions, heartbeat) of non-invasive indicators. In addition, a pilot study was conducted on-farm to assess the feasibility of two alternative methods, CB and nitrogen gasification (N2), and to survey farmers’ opinions on them. The onset of convulsions was almost immediate for both methods in the first study. No differences between CD and CB were observed for the cessation of pain response for chickens at age of 2 weeks (5.0 and 7.5 s, respectively) and 6 weeks (14.0 and 14.1 s, respectively). However, at 4 weeks a longer pain response was measured after CD (11.3 s) than after CB (4.7 s). For the three age categories, the pupillary light reflex disappeared later after CD (54.9 - 80.7 s) compared to CB (8.3 - 13.7 s). The same was observed for cessation of convulsions in 2- and 6-week-old chickens (185.3 and 172.0 s for CD and 79.0 and 82.9 s for CB). This suggests that brain death occurred faster after CB compared to CD. No difference between the methods was found for the cessation of the heartbeat. After the pilot study, the producers preferred N2 over CB in terms of animal-friendliness, time-efficiency, ease of use, and effectiveness. However, both methods were found rather expensive and required some experience. CB and N2 are good killing alternatives to CD due to rapid and irreversible insensibility. However, more information and support for chicken producers will be needed for these to become routine killing methods.

Broiler Chicken Behavior and Activity Are Affected by Novel Flooring Treatments

The objective was to determine broiler chicken behavioral differences in response to novel flooring treatments. Broilers (n = 182) were housed in 14 pens (a random subset from a larger-scale study including 42 pens), with 13 birds/pen. One of seven flooring treatments were randomly allocated to 14 pens (2 pens per treatment). The flooring treatments (provided from day 1 {1} or day 29 {29}) included regularly replaced shavings (POS), a mat with 1% povidone-iodine solution (MAT), and the iodine mat placed on a partially slatted floor (SLAT). In addition, a negative control treatment was included with birds kept on used litter from day 1 (NEG). Behavior was recorded in weeks 1, 2, 5, and 6. In week 5, treatments affected the behavioral repertoire (p ≤ 0.035). Birds in POS-1 showed more locomoting, preening and activity overall compared to MAT and/or SLAT treatments. Birds in POS-29 showed more drinking, foraging, preening and overall activity than birds in MAT and/or SLAT treatments. In week 6, birds in the POS-1 treatment spent more time foraging compared to birds in all MAT and SLAT treatments (p ≤ 0.030). In addition, birds in the POS-1 treatment spent more time preening than birds in the MAT-1 treatment (p = 0.046). Our results indicate that access to partially slatted flooring and/or disinfectant mats does not benefit broiler chicken welfare in terms of their ability to express highly motivated behaviors. Access to clean, regularly replaced litter is beneficial for broiler chicken welfare in terms of their ability to express their normal behavioral repertoire.

Environmental complexity positively impacts affective states of broiler chickens

Affective state can bias an animal's judgement. Animals in positive affective states can interpret ambiguous cues more positively ("optimistically") than animals in negative affective states. Thus, judgement bias tests can determine an animal's affective state through their responses to ambiguous cues. We tested the effects of environmental complexity and stocking density on affective states of broiler chickens through a multimodal judgement bias test. Broilers were trained to approach reinforced locations signaled by one color and not to approach unreinforced locations signaled by a different color. Trained birds were tested for latencies to approach three ambiguous cues of intermediate color and location. Broilers discriminated between cues, with shorter latencies to approach ambiguous cues closest to the reinforced cue than cues closest to the unreinforced cue, validating the use of the test in this context. Broilers housed in high-complexity pens approached ambiguous cues faster than birds in low-complexity pens-an optimistic judgement bias, suggesting the former were in a more positive affective state. Broilers from high-density pens tended to approach all cues faster than birds from low-density pens, possibly because resource competition in their home pen increased food motivation. Overall, our study suggests that environmental complexity improves broilers' affective states, implying animal welfare benefits of environmental enrichment.

Effect of Environmental Complexity and Stocking Density on Fear and Anxiety in Broiler Chickens

Barren housing and high stocking densities may contribute to negative affective states in broiler chickens, reducing their welfare. We investigated the effects of environmental complexity and stocking density on broilers' attention bias (measure of anxiety) and tonic immobility (measure of fear). In Experiment 1, individual birds were tested for attention bias (n = 60) and in Experiment 2, groups of three birds were tested (n = 144). Tonic immobility testing was performed on days 12 and 26 (n = 36) in Experiment 1, and on day 19 (n = 72) in Experiment 2. In Experiment 1, no differences were observed in the attention bias test. In Experiment 2, birds from high-complexity pens began feeding faster and more birds resumed feeding than from low-complexity pens following playback of an alarm call, suggesting that birds housed in the complex environment were less anxious. Furthermore, birds housed in high-density or high-complexity pens had shorter tonic immobility durations on day 12 compared to day 26 in Experiment 1. In Experiment 2, birds from high-density pens had shorter tonic immobility durations than birds housed in low-density pens, which is contrary to expectations. Our results suggest that birds at 3 weeks of age were less fearful under high stocking density conditions than low density conditions. In addition, results indicated that the complex environment improved welfare of broilers through reduced anxiety.

Habituation Protocols Improve Behavioral and Physiological Responses of Beef Cattle Exposed to Students in an Animal Handling Class

Simple Summary

Students in agricultural programs have the opportunity to interact with animals during different teaching activities. However, students’ interactions with livestock may be distressing to the animals and can affect the students’ and animals’ safety. We investigate whether two human-animal habituation strategies, one with positive tactile stimulation and one without, would improve behavioral and physiological responses of beef heifers during a livestock handling class. Overall, heifers that received a habituation treatment had more positive behavior responses, and decreased physiological stress responses in comparison to heifers that were not exposed to habituation. Furthermore, the heifers exposed to the habituation with a positive tactile stimulation had the greatest improvements in behavior in comparison to control and non-stimulated heifers, exhibiting more positive behaviors when interacting with humans. Strategies to habituate cattle to human interaction with positive stimulation aligned with training humans that handle and interact with cattle on best practices and cattle behavior can improve behavior, reduce stress-related physiological responses and enhance safety for both humans and animals.

Abstract

Our objective was to determine the impact of different habituation protocols on beef cattle behavior, physiology, and temperament in response to human handling. Beef heifers were exposed to three habituation strategies: (1) tactile stimulation (brushing) in the working chute for seven consecutive days (STI; n = 18); (2) passage through the working chute for seven consecutive days (CHU; n = 19) and; (3) no habituation (CON; n = 19). Individual heifer respiratory rate (RR; n/min), internal vaginal temperature (VAGT; °C), and blood cortisol were measured. Further, behavior parameters were observed to generate a behavior score, and heifer interaction with students and their behavioral responses were recorded. Habituation with STI and CHU resulted in improved numerical behavioral scores compared to CON, and greater (p ≤ 0.05) handling latencies. Vaginal temperature was decreased in STI compared to CHU and CONT (p ≤ 0.05). Cortisol concentration did not differ among treatments, but decreased (p ≤ 0.05) from the start of the experiment to 14 days after treatment initiation. Both habituation protocols showed benefits, but heifers that received the positive tactile stimulation in the chute had the greatest behavior improvements. Furthermore, these heifers responded more calmly during student-animal interactions in class, which is beneficial for the students’ and animals’ safety.

[Outpatient clinic for users of anabolic androgenic; experiences and practical tools]

In the Netherlands, an estimated 20,000 men abuse illegal androgens. The confrontation with a patient who uses illegal substances can evoke questions and emotions. We advise not to moralize users of anabolic steroids, but to strive for harm reduction by starting a discussion about the pros and cons of androgen abuse, taking into account your assumptions and judgments about this subject. Underlying psychopathology should be recognized and treated if the user is open to it. We recommend against prescribing anabolic steroids without medical indication and not to perform health checks routinely while the patient continues using anabolic steroids as long as it is not established that this can prevent health damage. If the user reports with health problems, this should be used as a starting point to (re) open the conversation about the advantages and disadvantages of use. Harmful effects of use must be handled according to appropriate guidelines.

Animal welfare assessment of on-farm euthanasia methods for individual, heavy turkeys

On-farm euthanasia of poultry, including turkeys, may not be possible for most people as birds gain weight; thus alternative mechanical methods have been developed. Our objective was to compare mechanical cervical dislocation with the Koechner Euthanizing Device (KED), captive bolt euthanasia with the Turkey Euthanasia Device (TED), head-only CO₂ euthanasia (CO₂), and electric euthanasia as potential humane methods for euthanizing individual, heavy turkeys. We assessed their impact on loss of brain stem reflexes, acute distress (corticosterone, CORT), kill success, torn skin, and blood loss. Turkeys (n = 174) were euthanized on 3 sampling days, while birds were restrained using a mobile bird euthanasia apparatus. Brain stem reflexes recorded were the cessation and return of induced nictitating membrane reflex (loss of consciousness and brain stem dysfunction), mouth gaping reflex (brain stem dysfunction), and musculoskeletal movements (spinal cord dysfunction). Overall, KED resulted in more frequent (at 4 min: KED 7 of 14; electric 0 of 13; TED 0 of 11; CO₂ 2 of 14 birds on day 1) and longer durations of the induced nictitating reflex compared to the other methods (means of day 2 and 3: KED 233; electric 15; TED 15; CO₂ 15 s). The mouth gaping reflex endured the longest after KED euthanasia (means of day 2 and 3: KED 197; electric 15; TED 51; CO₂ 15 s). Musculoskeletal movements endured longest after KED euthanasia (means of day 2 and 3: KED 235; electric 15; TED 219; CO₂ 15 s). Returning reflexes were more frequent after KED and TED compared to CO₂ and electric euthanasia, where it was absent. CO₂, electric, and TED euthanasia showed comparable kill success (success: CO₂ 42 out of 43; electric 44 of 45; TED 42 of 44), with KED resulting in most unsuccessful kills (unsuccessful: 8 out of 42). CORT responses were inconsistent. Torn skin and blood loss occurred more frequently after KED and TED compared to CO₂ and electric applications. Therefore, we conclude that, based on a comparison of these 4 methods, the most discernibly humane was electric euthanasia, which consistently resulted in quick loss of consciousness within 15 s, no returning reflexes, and no torn skin or blood loss.

Killing individual poultry on-farm-a survey among veterinarians and farmers

To date, information about reasons to select and kill poultry on-farm and which method veterinarians and poultry producers preferably use is scarce. Little is also known about their knowledge of the legislation regarding on-farm killing methods and of methods alternative to the one(s) they use, as well as their perception of those alternatives. In this study, Flemish poultry veterinarians (n = 13), broiler chicken producers (n = 27), and turkey producers (n = 4) were surveyed on killing methods they currently use in practice and alternative methods, on their opinion about what constitutes an appropriate method for on-farm killing of poultry, and on their reasons for killing. All poultry veterinarians and chicken producers who filled out the survey kill poultry by manual cervical dislocation (CD), whereas some turkey farmers also indicated killing by percussive blow to the head (n = 1) or exsanguination (n = 1). Turkey producers seem to be more inclined not to kill animals with injuries or symptoms of disease as compared to veterinarians or chicken producers, such that moribund turkeys are more likely to remain in the flock. Veterinarians considered the following properties of a killing method important: animal friendliness, applicability inside the stable, a high success rate, and time efficiency. Producers ranked the properties similarly, but for them, ease of performance and cost-efficiency were more important than applicability inside the stable. Producers scored those killing properties rather positively for manual as well as mechanical CD. Veterinarians and chicken producers considered the captive bolt method to be easy to perform, to have a high success rate, to be feasible to perform in the stable, and to be animal-friendly. Turkey producers, however, had doubts about the latter 2 properties. Gas, injection, and electrocution were inferior methods to kill poultry according to producers. In conclusion, manual CD is the most common method for killing broiler chickens and turkeys, and knowledge of, and experience with, alternative methods is very limited, both among veterinarians and producers. Informing them about legislation and training for the use of alternative killing techniques are recommended.

Euthanasia: Manual versus Mechanical Cervical Dislocation for Broilers

Simple Summary

Poultry are euthanized for several reasons, most commonly because a bird is sick or injured and unable to eat or drink. Euthanasia can be a challenge to perform, especially when birds are heavy, like broiler chickens (produced for meat). Manual cervical dislocation (CD), or “breaking the neck”, is the most commonly applied method, but can be challenging. Therefore, using a tool (the mechanical method) such as the Koechner Euthanizing Device (KED) could be an alternative. Here, we aimed to compare CD with KED application for their impact on duration of induced reflexes and time to brain death. We assessed loss of brain stem reflexes, which indicate deep unconsciousness and/or brain stem death, and cessation of musculoskeletal movements. We applied both methods (CD and KED) to 200 broilers of 36, 42, or 43 days old on 3 experimental days. On days 2 and 3 an additional method was added, in which the bird’s head was extended at a ~90° angle after the application of the KED (KED+). Our study indicated brain stem death occurred sooner when birds were euthanized with CD compared to KED or KED+; all reflex durations were sustained for longer in the KED and KED+ birds.

Abstract

The aim was to assess the onset of brain stem death for two euthanasia methods—manual cervical dislocation (CD) versus the Koechner Euthanizing Device (KED). Over three days broilers of 36 (n = 60), 42 (n = 80), or 43 days old (n = 60) were euthanized. On days 2 and 3, a treatment was added in which the bird’s head was extended at a ~90° angle after application of the KED (KED+). On those days, gap size was recorded between the skull and atlas vertebra by 1-cm increments. The onset of brain death was assessed by recording the nictitating membrane reflex, gasping reflex and musculoskeletal movements (sec). Additionally, skin damage and blood loss were recorded (y/n). On all days, CD resulted in quicker loss of reflexes and movements compared to KED or KED+. Reflexes returned in 0–15% of CD birds, 50–55% of KED birds, and 40–60% of KED+ birds, possibly regaining consciousness. Skin damage occurred in 0% of CD birds, 68–95% of KED birds, and 85–95% of KED+ birds. On day 2 (p = 0.065) and 3 (p = 0.008), KED birds had or tended to have a narrower skull-to-atlas gap compared to CD and KED+ birds. Based on our results, CD would be the recommended method for broilers.

Impact of transportation duration on stress responses in day-old chicks from young and old breeders

The aim of this study was to assess the interaction effect of transportation duration and parental age on physiological stress responses and quality in day-old chicks. After hatch, 3240 chicks from either 29-week old (young) or 60-week old (old) broiler breeders were transported for 1.5h (short) or 11h (long). Thereafter, 228 chicks were assessed for quality and blood plasma was assayed for corticosterone (CORT), lactate, glucose, and thiobarbituric acid-reactive substances (TBARS, increased concentrations can indicate oxidative stress). No interaction effects of parental age and transportation duration were found (all P>0.10). Chicks from young breeders showed higher CORT levels (P=0.007) and were of higher quality (Tona method, P<0.001) than those from old breeders. After long transportation, chicks showed increased CORT (P<0.001) and lower TBARS levels (P<0.001) compared to after short transportation. No evidence was provided that long transportation differently affected the quality or stress responses of chicks from breeder flocks of two ages.

Abstract P2-01-09: The development of nomograms to predict axillary lymph node status in breast cancer patients

This abstract was withdrawn by the authors.

Broiler chickens dead on arrival: associated risk factors and welfare indicators

The pre-slaughter phase of the production process has potentially important animal welfare implications, including mortality (recorded as "Dead on Arrivals"; DOA: ). To reduce DOA%, specific risk factors need to be identified. DOA% can also be used as a first and quick screening of pre-slaughter broiler welfare under commercial conditions. The aim of the present study was to identify risk factors for DOA% in commercial broiler flocks and to find associations between DOA% and animal-based indicators of broiler welfare during the pre-slaughter phase. Eighty-one transported flocks to five slaughter plants were assessed. Farmers provided information on the flock and observers gathered data on pre-slaughter factors. DOA% was recorded by slaughter plant personnel. The association between risk factors and DOA% was tested using linear mixed models, with slaughter plant as the random effect. Mean (± SE) DOA% was 0.30 ± 0.05% and median was 0.19% (range 0.04 to 3.34%). Two risk factors for DOA% were identified, both related to flock health status during the production phase. Higher DOA% was found when farmers did not check chick quality upon arrival (P = 0.011), although one extreme DOA% caused this significant effect. In addition, on-farm mortality during production (including selective culling) was negatively associated with DOA% (P = 0.011), potentially due to the selective culling on farm. Further research is needed on the impact of on-farm health status on welfare during the pre-slaughter phase, as the current study provided some evidence that on-farm factors are linked to mortality during the pre-slaughter phase. No specific characteristics of the pre-slaughter phase could be identified as risk factor for increased mortality. DOA% was positively associated with five welfare indicators, including indicators of thermal stress, which indicates the potential to use DOA% as a quick, cost-efficient screening tool for those welfare aspects.

Effect of post-hatch transportation duration and parental age on broiler chicken quality, welfare, and productivity

Broiler chicks are transported to production sites within one to 2 d post-hatch. Possible effects of this transportation are poorly understood and could vary among chicks from breeder flocks of different ages. The aim of the present study was to investigate the effects of transportation duration and parental flock age on chick welfare, productivity, and quality. After hatch in a commercial hatchery, 1,620 mixed-sex chicks from 29-wk old (young) and 1,620 chicks from 60-wk old (old) breeders were subjected to transportation of 1.5 h or 11 h duration. After transportation, 2,800 chicks were divided among 100 pens, with each pen containing 28 chicks from one transportation crate (2 or 3 pens per crate). From the remaining chicks, on average 6 chicks (min 4, max 8) per crate (n = 228) were randomly selected and assessed for chick quality, weighed, and culled for yolk sac weighing (one d). Chicks that had not been assigned to pens or were not used for post-transportation measurements, were removed from the experiment (n = 212). Mortality, ADG, BW, and feed conversion ( FC: ) of the experimental chicks were recorded until 41 d. Meat quality was measured for breast fillets (n = 47). No interaction effect of parental age and transportation duration was found for any variables. BW and yolk sac weight at one d were lower for chicks transported 11 h than 1.5 h and for chicks from young versus old breeders. The effect of parental flock age on BW persisted until slaughter. Additionally, parental age positively affected ADG until slaughter. Chick quality was lower in chicks from old versus young breeders. Chick quality and productivity were not affected by transportation duration. Mortality and meat quality were not affected by either parental age or transportation duration. To conclude, no long-term detrimental effects were found from long post-hatch transportation in chicks from young or old parent flocks. Based on these results, we suggest that 11 h post-hatch transportations under similar conditions do not impose long-term welfare or productivity risks.

The MC1R Gene and Youthful Looks

Looking young for one's age has been a desire since time immemorial. This desire is attributable to the belief that appearance reflects health and fecundity. Indeed, perceived age predicts survival [1] and associates with molecular markers of aging such as telomere length [2]. Understanding the underlying molecular biology of perceived age is vital for identifying new aging therapies among other purposes, but studies are lacking thus far. As a first attempt, we performed genome-wide association studies (GWASs) of perceived facial age and wrinkling estimated from digital facial images by analyzing over eight million SNPs in 2,693 elderly Dutch Europeans from the Rotterdam Study. The strongest genetic associations with perceived facial age were found for multiple SNPs in the MC1R gene (p < 1 × 10(-7)). This effect was enhanced for a compound heterozygosity marker constructed from four pre-selected functional MC1R SNPs (p = 2.69 × 10(-12)), which was replicated in 599 Dutch Europeans from the Leiden Longevity Study (p = 0.042) and in 1,173 Europeans of the TwinsUK Study (p = 3 × 10(-3)). Individuals carrying the homozygote MC1R risk haplotype looked on average up to 2 years older than non-carriers. This association was independent of age, sex, skin color, and sun damage (wrinkling, pigmented spots) and persisted through different sun-exposure levels. Hence, a role for MC1R in youthful looks independent of its known melanin synthesis function is suggested. Our study uncovers the first genetic evidence explaining why some people look older for their age and provides new leads for further investigating the biological basis of how old or young people look.

The direct impact of landslides on household income in tropical regions: A case study from the Rwenzori Mountains in Uganda

Landslides affect millions of people worldwide, but theoretical and empirical studies on the impact of landslides remain scarce, especially in Sub-Saharan Africa. This study proposes and applies a method to estimate the direct impact of landslides on household income and to investigate the presence of specific risk sharing and mitigation strategies towards landslides in a tropical and rural environment. An original cross-sectional household survey is used in combination with geographical data to acquire detailed information on livelihoods and on hazards in the Rwenzori mountains, Uganda. Ordinary least square regressions and probit estimations with village fixed effects are used to estimate the impact of landslides and the presence of mitigation strategies. Geographical information at household level allows to disentangle the direct impact from the indirect effects of landslides. We show that the income of affected households is substantially reduced during the first years after a landslide has occurred. We find that members of recently affected households participate more in wage-employment or in self-employed activities, presumably to address income losses following a landslide. Yet, we see that these jobs do not provide sufficient revenue to compensate for the loss of income from agriculture. Given that landslides cause localized shocks, finding a significant direct impact in our study indicates that no adequate risk sharing mechanisms are in place in the Rwenzori sub-region. These insights are used to derive policy recommendations for alleviating the impact of landslides in the region. By quantifying the direct impact of landslides on household income in an agricultural context in Africa this study draws the attention towards a problem that has been broadly underestimated so far and provides a sound scientific base for disaster risk reduction in the region. Both the methodology and the findings of this research are applicable to other tropical regions with high landslide densities.

Efficacy of newer versus older antihypertensive drugs in black patients living in sub-Saharan Africa

To address the epidemic of hypertension in blacks born and living in sub-Saharan Africa, we compared in a randomised clinical trial (NCT01030458) single-pill combinations of old and new antihypertensive drugs in patients (30-69 years) with uncomplicated hypertension (140-179/90-109 mm Hg). After ≥4 weeks off treatment, 183 of 294 screened patients were assigned to once daily bisoprolol/hydrochlorothiazide 5/6.25 mg (n=89; R) or amlodipine/valsartan 5/160 mg (n=94; E) and followed up for 6 months. To control blood pressure (<140/<90 mm Hg), bisoprolol and amlodipine could be doubled (10 mg per day) and α-methyldopa (0.5-2 g per day) added. Sitting blood pressure fell by 19.5/12.0 mm Hg in R patients and by 24.8/13.2 mm Hg in E patients and heart rate decreased by 9.7 beats per minute in R patients with no change in E patients (-0.2 beats per minute). The between-group differences (R minus E) were 5.2 mm Hg (P<0.0001) systolic, 1.3 mm Hg (P=0.12) diastolic, and 9.6 beats per minute (P<0.0001). In 57 R and 67 E patients with data available at all visits, these estimates were 5.5 mm Hg (P<0.0001) systolic, 1.8 mm Hg (P=0.07) diastolic and 9.8 beats per minute (P<0.0001). In R compared with E patients, 45 vs 37% (P=0.13) proceeded to the higher dose of randomised treatment and 33 vs 9% (P<0.0001) had α-methyldopa added. There were no between-group differences in symptoms except for ankle oedema in E patients (P=0.012). In conclusion, new compared with old drugs lowered systolic blood pressure more and therefore controlled hypertension better in native African black patients.