Slaughter of animals: poultry

Impact of nanoscale silicon dioxide coating of stainless-steel surfaces on Listeria monocytogenes

High resistance to environmental factors as well as the ability to form biofilms allow Listeria monocytogenes to persist for a long time in difficult-to-reach places in food-producing plants. L. monocytogenes enters final products from contaminated surfaces in different areas of plants and poses a health risk to consumer. Modified surfaces are already used in the food industry to prevent cross-contamination. In this study, stainless-steel surfaces were coated with nanoscale silicon dioxide and the effects on attachment, bacterial growth and detachment of L. monocytogenes were evaluated. Attachment was considered for three different ways of application to simulate different scenarios of contamination. Bacterial growth of L. monocytogenes on the surface was recorded over a period of up to 8 h. Detachment was tested after cleaning inoculated stainless-steel surfaces with heated distilled water or detergent. Coating stainless-steel surfaces with nanoscale silica tends to reduce adherence and increased detachment and does not influence the bacterial growth of L. monocytogenes. Further modifications of the coating are necessary for a targeted use in the reduction of L. monocytogenes in food-processing plants.

Alternatives to Carbon Dioxide in Two Phases for the Improvement of Broiler Chickens' Welfare during Stunning

This study evaluated the exposure to gas mixtures of carbon dioxide (CO2) associated with nitrogen (N2) as alternatives to CO2 in two phases to improve the welfare of broiler chickens at slaughter. Broilers were exposed to one of three treatments: 40C90C (1st phase: <40% CO2 for 2 min; 2nd phase: >90% CO2 and <2% O2 for 2 min, n = 92), 40C60N (40% CO2, 60% N2, and <2% O2 for 4 min, n = 79), or 20C80N (20% CO2, 80% N2, and <2% O2 for 4 min, n = 72). Brain activity (EEG) was assessed to determine the onset of loss of consciousness (LOC) and death. Behavioural assessment allowed for characterisation of an aversive response to the treatments and confirmed loss of posture (LOP) and motionlessness as behavioural proxies of LOC and brain death in 40C60N and 20N80C. However, the lack of quality of the EEG traces obtained in 40C90C did not allow us to determine the onset of LOC and brain death for this treatment. The onset of LOC in 40C60N was found at 19 s [14-30 s] and in 20C80N at 21 s [16-37 s], whereas a LOP was seen at 53 s [26-156 s] in 40C90C. Birds showed brain death in 40C60N at 64 s [43-108 s] and in 20C80N at 70 s [45-88 s]), while they became motionless in 40C90C at 177 s [89-212 s]. The 40C90C birds not only experienced more events of aversive behaviours related to mucosal irritation, dyspnoea, and breathlessness during induction to unconsciousness but were at risk of remaining conscious when the CO2 concentration was increased in the 2nd phase (known to cause severe pain). From an animal welfare point of view, 40C60N proved to be the least aversive of the three treatments tested, followed by 20C80N and 40C90C.

Opportunities for Regulatory Authorities to Assess Animal-Based Measures at the Slaughterhouse Using Sensor Technology and Artificial Intelligence: A Review

Animal-based measures (ABMs) are the preferred way to assess animal welfare. However, manual scoring of ABMs is very time-consuming during the meat inspection. Automatic scoring by using sensor technology and artificial intelligence (AI) may bring a solution. Based on review papers an overview was made of ABMs recorded at the slaughterhouse for poultry, pigs and cattle and applications of sensor technology to measure the identified ABMs. Also, relevant legislation and work instructions of the Dutch Regulatory Authority (RA) were scanned on applied ABMs. Applications of sensor technology in a research setting, on farm or at the slaughterhouse were reported for 10 of the 37 ABMs identified for poultry, 4 of 32 for cattle and 13 of 41 for pigs. Several applications are related to aspects of meat inspection. However, by European law meat inspection must be performed by an official veterinarian, although there are exceptions for the post mortem inspection of poultry. The examples in this study show that there are opportunities for using sensor technology by the RA to support the inspection and to give more insight into animal welfare risks. The lack of external validation for multiple commercially available systems is a point of attention.

Shaping Poultry Meat Quality Attributes in the Context of Consumer Expectations and Preferences-A Case Study of Poland

The optimisation of poultry meat quality attributes at the industrial level requires getting to know the changing customer needs and expectations to justify further measures taken in the future to improve the production process. This article was aimed at the following: (1) to identify and assess consumer expectations and behaviour in relation to the quality criteria for poultry meat offered on the market in Poland, and (2) to identify the significance of the sensory characteristics of poultry meat, mainly variegated colours on its surface, as a criterion for creating the expected quality in a shop. The study results showed that the attributes which significantly lower the quality and commercial value of meat are the defects noticeable on the fillet surface, namely discolouration and hematomas, which are mainly caused during the poultry stunning. The absence of noticeable bruising or hematomas and a uniform colour on the fillet surface are the main attributes of high-quality poultry meat retail cuts, which are expected by consumers. A recommendation for poultry meat producers is that bruising and hematomas need to be eliminated and that the offer should be adjusted to Polish consumers' expectations about the quality attributes of the meat offered on the market. The elimination of these meat defects will be possible, e.g., through the introduction of innovative technical solutions into the poultry stunning process, which will improve meat quality at its production stage.

Importance of Knife Sharpness during Slaughter: Shariah and Kosher Perspective and Scientific Validation

Halal and kosher slaughter have given the utmost importance to the sharpness of knives during the slaughter of animals. A sharp knife of appropriate dimension (blade length) makes slaughter less painful during neck severance and facilitates desirable bleeding. The role of knife sharpness has not been given due credit from an animal welfare perspective and is likely ignored by the people involved in slaughterhouses. A neat, clean, and efficient neck cut by an extremely sharp knife reduces the pain. It improves the bleeding out, thus making animals unconscious early without undergoing unnecessary pain and stress. It also helps in improving meat quality and food safety. A slight incremental improvement in knife sharpness could significantly improve the animal welfare, productivity, efficiency, and safety of meat plant workers. The present review critically analyzed the significance of knife sharpness in religious slaughter by reducing stress and pain and improving meat quality and food safety. The objective quantification of knife sharpness, proper regular training of slaughterers, and slow slaughter rate are the challenges faced by the meat industry.

Effect of halal and stunning slaughter methods on meat quality: A review

The handling and slaughtering processes for animals have a significant effect on meat quality. Islamic (halal) slaughter and many different stunning methods are used in the meat industry worldwide. The objective of the present review was to update the current literature and practices concerning halal slaughter and stunning methods, and their effects on meat quality. The present review used inductive reasoning and comparison between halal and stunning methods for the slaughtering of farm animals. Halal slaughter involves cutting the carotid arteries, jugular veins, oesophagus, and throat without stunning. Halal slaughter facilitates the draining of blood from the animal, which is necessary to produce high-quality meat with good conservation and increased shelf life. On the other hand, most stunning slaughter hinders the bleeding process in sheep and goats. The retained blood content may act as a suitable medium for the growth and multiplication of different kinds of harmful microorganisms and make badly bled meat hard to preserve. Proper halal slaughter has several advantages regarding meat quality in comparison to stunning methods, and requires greater management attention pre-, during, and post-slaughtering to maintain good welfare and the production of high-quality meat.

Relevant Indicators of Consciousness after Waterbath Stunning in Turkeys and Stunning Efficiency in Commercial Conditions

The prevalence and inter-observer repeatability of the four most valid and feasible indicators of consciousness after waterbath stunning in turkeys were evaluated before bleeding (i.e., tonic convulsion, breathing, spontaneous blinking and vocalization) and during bleeding (i.e., fluttering, breathing, spontaneous swallowing and head shaking). Furthermore, correlations between them were calculated to further understand the association between such indicators. This study compared the assessments of four observers on 7877 turkeys from 28 flocks slaughtered in eight different abattoirs. Repeatability between observers was assessed by combining the crude percentage of agreement and the Fleiss' kappa. Before bleeding, tonic seizure was observed to be not reliable under commercial conditions and spontaneous blinking and vocalization had poor repeatability. During bleeding, spontaneous swallowing was not observed and head shaking had poor repeatability. Hence, the most relevant indicators of consciousness before bleeding is breathing while during bleeding is breathing and wing flapping. Moreover, the stunning efficiency of the key electrical parameters used in the different slaughterhouses was assessed. Therefore, a refined list of indicators of the state of consciousness after waterbath stunning is proposed to be used in commercial turkey slaughterhouses to ensure consistency of controls. On the other hand, the range of the prevalence of turkeys with indicators of consciousness within a batch found before bleeding [0-16%] and after bleeding [0-18%] highlights the importance of controls.

Welfare of domestic birds and rabbits transported in containers

This opinion, produced upon a request from the European Commission, focuses on transport of domestic birds and rabbits in containers (e.g. any crate, box, receptacle or other rigid structure used for the transport of animals, but not the means of transport itself). It describes and assesses current transport practices in the EU, based on data from literature, Member States and expert opinion. The species and categories of domestic birds assessed were mainly chickens for meat (broilers), end-of-lay hens and day-old chicks. They included to a lesser extent pullets, turkeys, ducks, geese, quails and game birds, due to limited scientific evidence. The opinion focuses on road transport to slaughterhouses or to production sites. For day-old chicks, air transport is also addressed. The relevant stages of transport considered are preparation, loading, journey, arrival and uncrating. Welfare consequences associated with current transport practices were identified for each stage. For loading and uncrating, the highly relevant welfare consequences identified are handling stress, injuries, restriction of movement and sensory overstimulation. For the journey and arrival, injuries, restriction of movement, sensory overstimulation, motion stress, heat stress, cold stress, prolonged hunger and prolonged thirst are identified as highly relevant. For each welfare consequence, animal-based measures (ABMs) and hazards were identified and assessed, and both preventive and corrective or mitigative measures proposed. Recommendations on quantitative criteria to prevent or mitigate welfare consequences are provided for microclimatic conditions, space allowances and journey times for all categories of animals, where scientific evidence and expert opinion support such outcomes.

The 'sustainability gap' of US broiler chicken production: trade-offs between welfare, land use and consumption

In 2018, over nine billion chickens were slaughtered in the United States. As the demand for chickens increases, so too have concerns regarding the welfare of the chickens in these systems and the damage such practices cause to the surrounding ecosystems. To address welfare concerns, there is large-scale interest in raising chickens on pasture and switching to slower-growing, higher-welfare breeds as soon as 2024. We created a box model of US chicken demographics to characterize aggregate broiler chicken welfare and land-use consequences at the country scale for US shifts to slower-growing chickens, housing with outdoor access, and pasture management. The US produces roughly 20 million metric tons of chicken meat annually. Maintaining this level of consumption entirely with a slower-growing breed would require a 44.6%-86.8% larger population of chickens and a 19.2%-27.2% higher annual slaughter rate, relative to the current demographics of primarily 'Ross 308' chickens that are slaughtered at a rate of 9.25 billion per year. Generating this quantity of slower-growing breeds in conventional concentrated animal feeding operations (CAFO) would require 90 582-98 687 km2, an increase of 19.9-30.6% over the 75 577 km2 of land used for current production of Ross 308. Housing slower-growing breeds on pasture, the more individually welfare-friendly option, would require 108 642-121 019 km2, a 43.8-60.1% increase over current land use. Allowing slower-growing breeds occasional outdoor access is an intermediate approach that would require 90 691-98 811 km2, an increase of 20-30.7% of the current land use, a very minor increase of land relative to managing slower-growing breeds in CAFOs. In sum, without a drastic reduction in consumption, switching to alternative breeds will lead to a substantial increase in the number of individuals killed each year, an untenable increase in land use, and a possible decrease in aggregate chicken welfare at the country-level scale. Pasture-based management requires substantial additional land use. These results demonstrate constraints and trade-offs in animal welfare, environmental conservation and food animal consumption, while highlighting opportunities for policies to mitigate impacts in an integrated manner using a One Health approach.

Separate collection and bio-waste valorization in the Italian poultry sector by material flow analysis

Poultry meat production and consumption face several challenges under economic, social and environmental perspectives, and increasing concerns are associated with food loss and waste minimization. One of the main issues is related to the absence of a homogeneous and standardized separate collection of bio-waste at country level, which makes chicken bones, skin and food waste valorization a challenging goal. The present research, implementing the material flow analysis to the Italian poultry sector, aims at measuring poultry-related co-products and by-products, exploring food waste, chicken bones and skin and the current trends in the Italian bio-waste separate collection. Then, it discusses alternative separate collection strategies and sustainable consumption habits. Data have been collected according to a research triangulation approach, whereas system boundaries consider slaughterhouse, distribution and final consumption stage. It emerges that more than 1.50 Mt of live animals have been processed to obtain 0.46 Mt of fresh meat and 0.76 Mt of co-products and by-products, of which more than 0.32 Mt are represented by chicken bones and skin. In addition, more than 0.15 Mt of food waste have been recorded. The research adds an extra step towards the identification of awareness campaigns and separate collection strategies at national level.

Effects of fully or partially slatted flooring designs on the performance, welfare and carcass characteristics of broiler chickens

1. The objective of this study was to evaluate the effects of fully (FSF) or partially (PSF) flooring designs on animal-based welfare indicators in a fast-growing broiler genotype. Growth performance and carcass characteristics were assessed.2. One-d-old male chicks were randomly assigned to three groups: fully slatted flooring (100% slatted floor), partially slatted flooring (50% litter floor and 50% slatted floor) and conventional floor pens with litter (control, 100% deep litter) with 5 replicates of 14 male chicks. The litter was rice hull, as is usual in practice.3. Measurements of live body weight, feed intake, feed conversion ratio, mortality and performance index were collected before depopulation at 42 d old. Welfare assessments were done by individual ante- and post-mortem carcass inspection during depopulation and after slaughter.4. Broiler live body weight (P < 0.03) and feed intake (P < 0.003) and ante-mortem welfare indicators (P < 0.001) were positively affected by FSF and PSF compared to the conventional deep litter system. Post-mortem lesion scores on wings and shoulder were similar in all floor types but there were significant differences for the lesions on breast (P < 0.003) and pygostyle (P < 0.05).5. In conclusion, FSF and PSF resulted in higher body weights, while reducing incidence of foot pad and hock joint deformations in live animals.

Effects of Season, Plumage Colour, and Transport Distance on Body Weight Loss, Dead-on-Arrival, and Reject Rate in Commercial End-of-Lay Hens

Simple Summary

The transport conditions of end-of-lay hens to slaughterhouses are essential for their welfare. In this study, the effect of season, plumage colour, and transport distance on body weight loss, dead-on-arrival rates, and reject rates was examined. Transport-related data of 31.6 million end-of-lay hens over a two-year period from one slaughter plant in Turkey were analysed. Hens transported in the winter and spring seasons had a greater body weight loss and reject rates. Brown-feathered hens had a higher death rate, while white-feathered hens had a higher body weight loss and reject rate. Hens transported longer distances for slaughter had increased body weight loss, death rates, and reject rates. These results indicate that more care should be taken when transporting end-of-lay hens in cold weather and over longer transport distances. We suggest the transport should be reduced to a certain distance, and improved conditions ought to be provided to mitigate losses.

Abstract

Transport conditions of end-of-lay hens are important for their welfare. This study investigated the effects of season, plumage colour, and transportation distance on the welfare of end-of-lay hens. Retrospective data from 31,667,274 end-of-lay hens transported to a poultry slaughterhouse in Turkey were analysed. The mean body weight loss, dead-on-arrival (DOA) rate, and reject rate were 3.723%, 1.397%, and 0.616%, respectively. The effects of season, plumage colour, and transport distance on the evaluated parameters were all statistically significant (p < 0.001). The highest body weight loss was found in winter, while the lowest body weight loss was found in autumn. The average DOA rate was highest in spring and lowest in autumn. The highest average reject rate was found in spring (0.630%). Body weight loss, DOA rates, and reject rates were also significantly different among white and brown hens (p < 0.001; p < 0.001; p = 0.016, respectively). The highest body weight loss and reject rates were found in white plumage hens, while the highest DOA rate was found in brown plumage hens. The body weight loss and DOA rate were positively correlated with transportation distance (p < 0.001). The results of this study indicate that more preventive measures should be taken during the transport of end-of-lay hens, especially in cold seasons such as winter, and over longer transport distances, in regard to the welfare of these animals. Additionally, the transport of these animals should be lessened to a certain distance.

The Influence of Broilers' Body Weight on the Efficiency of Electrical Stunning and Meat Quality under Field Conditions

Simple Summary

Water-bath stunning represents the most-applied stunning system in poultry slaughtering. This study aimed to assess the efficiency of two types of electrical equipment applied to broilers with different live body weights. Moreover, the influence of the tested stunners on broiler meat quality was evaluated. 6600 broilers, divided into three weight groups, were stunned and the state of unconsciousness and post-mortem defects were evaluated by blinded trained operators. Considering the total body weight, the application of the two stunning systems resulted in a different occurrence of ineffective stunning signs registering statistical differences (p < 0.01) among groups. Considering injuries, an inverse relationship between body weight and lesions was found. The results highlighted the effectiveness of both stunning systems that apply the best combination of electrical parameters, taking into account the weight of the animal and ensuring its welfare.

Abstract

Water-bath stunning represents the most-applied stunning system in poultry slaughtering, but within the European Union, specific indications on electric parameters that should be used, such as voltage, are missing. The objective of this study was to evaluate the efficiency of two commercially available types of electrical equipment (A and B) on broilers with different live body weights and the influence of the tested parameters on meat quality. Experimental trials in a European Union-approved slaughterhouse were carried out using two different stunners. 6600 broilers, divided into three weight groups, were stunned applying different protocols based on the same current frequencies and intensity but different voltages. The state of unconsciousness (presence of corneal reflex and wings flapping) and post-mortem defects (pectoral hemorrhages and dark meat) were evaluated by blinded trained operators. The presence of corneal reflex and petechiae were the most reported consciousness signs and post-mortem injuries, respectively. Different weights played an important role within stunner A, registering statistical differences (p < 0.01) among groups. Considering injuries, an inverse relationship between body weight and lesions was found. The results highlighted the effectiveness of both stunning systems applying the best combination of electrical parameters considering the weight of the animal and ensuring its well-being.