Tesi sul tema "Stunning and slaughter"

This thesis describes experimental work conducted to define factors associated with the occurrence of ecchymosis (blood splash) in fallow deer, and discusses facets of the Australian venison processing sector with respect to its capacity to improve the quality of venison. Data was collected on 1804 deer slaughtered experimentally (n equals 494) or at commercial works (n equals 1310) in a range of different slaughter systems. The study showed that a number of factors contribute to the expression of ecchymosis in the carcases of slaughtered deer, and the tailoring of slaughter procedures to suit particular slaughter systems is likely to reduce the extent to which ecchymosis occurs.
Doctor of Philosophy (PhD)

Orientador : Profª. Drª. Carla Forte Maiolino Molento
Co-orientador : Prof. Dr. Ricardo Vilani e Profª. Drª. Elizabeth Santin
Dissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências Agrárias, Programa de Pós-Graduação em Ciências Veterinárias. Defesa: Curitiba, 27/03/2015
Inclui referências : f. 18-20;47-56;70-75;92-96
Área de concentração : Nutrição e alimentação animal
Resumo: No Brasil, em 2011 foram produzidas 544.490 toneladas de peixes provenientes da aquicultura. A preocupação com o grau de bem-estar dos animais destinados à produção de alimentos é crescente no mundo ocidental. No entanto, os métodos tradicionais de abate de peixes causam um alto grau de sofrimento e estudos de métodos de abate humanitário em espécies nativas ainda são escassos. Além disso, as regulamentações de abate de animais de produção não incluem peixes. Desta forma, este trabalho teve como objetivo estudar parâmetros para eletronarcose de duas espécies, assim como conhecer a percepção de cidadãos da América Latina em relação à senciência, bem-estar e abate humanitário de peixes. Este estudo divide-se em cinco capítulos: (1) Apresentação; (2) Percepção sobre senciência, bem-estar e abate humanitário de peixes por cidadãos da América Latina; (3) Eletronarcose em pacu (Piaractus mesopotamicus); (4) Eletronarcose em jundiá (Rhamdia quelen) e (5) Considerações finais. O capítulo sobre a percepção dos cidadãos mostrou que os respondentes consideram os peixes como seres sencientes. A classificação da percepção de senciência entre os diferentes grupos taxonômicos parece estar em concordância com a proximidade filogenética, sugerindo uma maior sensibilidade com os mamíferos. Os cidadãos perceberam um alto grau de sofrimento em cenários de pesca esportiva, feira do peixe vivo e peixes usados em laboratórios. Além disso, os respondentes concordaram com a inclusão dos peixes nas normativas de abate humanitário. Os capítulos sobre electronarcose permitiram entender parâmetros de insensibilização elétrica com tempos de inconsciência maior que 1 min, sem alterações significativas no pH muscular e rigor mortis das carcaças. Ainda, os parâmetros foram seguros em termos de evitar fraturas, hemorragias ou petéquias nas carcaças. Os resultados obtidos apontam para a necessidade de desenvolvimento de pesquisa visando melhorar as atuais práticas de abate de peixes no Brasil, assim como a relevância de incluir os peixes na regulamentação de abate humanitário. Novos estudos são necessários para fornecer ferramentas aplicáveis na indústria, de modo de instaurar práticas de abate humanitário em peixes que diminuam o sofrimento de um grande número de indivíduos. Palavras-chave: Abate humanitário. Bem-estar animal. Eletronarcose. Inconsciência. Percepção. Sofrimento. Termonarcose.
Abstract: In Brazil, in 2011 it was produced 544,490 tons of fish from aquaculture. The concern with the level of welfare of animals for food production is increasing in the Western world. However, traditional methods of killing fish cause a high degree of suffering and studies of humane slaughter methods in native species are still scarce. Furthermore, the most regulations slaughter of farm animals include do not include fish. Thus, this work aimed to study parameters for electrical stunning in two species and to study the perception on fish sentience, welfare and slaughter by citizens from Bogotá, Colombia, and Curitiba, Brazil. This study is divided into five chapters: (1) Presentation; (2) Perception on fish sentience, welfare and humane slaughter by Latin American citizens; (3) Electrical stunning in pacu (Piaractus mesopotamicus); (4) Electrical stunning in South American catfish (Rhamdia quelen) and (5) Final considerations. The chapter on the perception of citizens showed that respondents consider the fish as sentient beings. The classification of sentience perception among taxonomic groups seems in accordance with the phylogenetic proximity to humans, suggesting greater sensitivity towards mammals. Citizens perceived a high degree of suffering in recreational angling, fair live fish and fish used in laboratories. In addition, respondents agreed with the inclusion of fish in humane slaughter regulations. The chapters on electrical stunning allowed identified parameters of electrical stunning to unconsciousness times greater than 1 min and no significant changes in muscle pH and rigor mortis of carcasses. Further, parameters used were safe in terms of avoiding fractures, bleeding or petechial in the carcasses. The results point to the need for research development to improve the current fish slaughtering practices in Brazil, as well as the importance of including fish in the regulation of humane slaughter. Further studies are needed to provide tools applicable in the industry in order to establish humane slaughter practices in fish reduce the suffering of a large number of individuals. Keywords: Animal welfare. Electrical stunning. Humane slaughter. Hypothermia. Perception. Suffering. Unconsciousness.

Moderne Schlachtsysteme tragen ein Risiko lebende Tiere weiterzuverarbeiten (SCHÜTTE und BOSTELMANN 2001, TROEGER 2005 und TROEGER und MEILER 2006). Gründe für dieses ernst zu nehmende tierschutzrelevante Problem sind eine ineffiziente Betäubung und/oder der Mangel an einer ausreichenden und schnellen Entblutung der Schweine. Die europäische Kommission hat 2009 die Verordnung (EG) Nr. 1099/2009 über den Schutz von Tieren zum Zeitpunkt der Tötung implementiert (ANON. 2009). Die Studie schafft Grundlagen um eine automatisierte Methode zu entwickeln, welche die Abwesenheit von Lebenszeichen von Schlachtschweinen verifiziert. Die Hypothese hierbei ist die Annahme, dass Schweine, die auf einen schmerzhaften Reiz wie heißes Wasser mehrere Minuten nach der Entblutung reagieren mit dem Risiko eines zumindest teilweise funktionierenden Gehirns behaftet sind. Die Studie fand an drei kommerziellen Schlachthöfen in Deutschland statt, die verschiedene elektrische Betäubungs- (Kopf-zu-Herz-Durchströmung) und Stechverfahren verwendeten. Insgesamt wurden am Schlachtband 5.301 Mastschweine im Hauptversuch untersucht und mittels Videokameras aufgezeichnet. Um die Abwesenheit von Lebenszeichen am Ende der Nachentblutestrecke, das heißt vier bis fünf Minuten nach Entblutestich, zu überprüfen wurde ein Heißwasser-Reiz mit 65 °C verwendet. Die Dauer der Reizapplikation betrug fünf bzw. 15 Sekunden. Eine automatisierte Reizapplikations-Anlage, erbaut von der Firma BANSS Schlacht- und Fördertechnik GmbH (Biedenkopf), induzierte den Stimulus vor allem im Bereich des Gesichts der Schweine. Als Referenz zu den Beobachtungen der Bewegungen während der Reiz-Applikation wurden Gehirnnerven-Reflexe (Corneal- und Lidschlussreflexe) und Reaktionen auf einen Kniff in die Nasenscheidewand klinisch untersucht. Schweine mit positiven Befunden wurden mittels Bolzenschuss nachbetäubt bzw. getötet. Die Sensitivität des Heißwasser-Tests lag bei 99 %. Eines von 75 Tieren wies positive Corneal- und Lidschlussreflexe auf, obwohl dieses Schwein auf den Heißwasser-Reiz nicht reagiert hatte. Jedoch konnten deutlich erkennbare Spontanbewegungen jenes Tieres bereits vorher beobachtet werden. Die Spezifität des Heißwasser-Tests lag bei 98 %. Beinah jedes Schwein mit negativen Gehirnnerven-Befunden blieb während der Reizapplikation unauffällig. 3,8 % (n = 199) der untersuchten Schweine zeigten eine Reaktion auf den Heißwasser-Reiz. Es war kein Unterschied zwischen dem fünf bzw. 15 Sekunden anhaltendem Reiz zu ermitteln. Neben einer ineffizienten Entblutung kann die reversible Betäubung als ein weiterer möglicher Grund für dieses Ergebnis genannt werden. Die Elektrische Betäubung ist reversibel, solange kein Herzkammerflimmern sicher ausgelöst wird (HOENDERKEN et al. 1980 und VOGEL et al. 2010). Es kann geschlussfolgert werden, dass die elektrische Kopf-zu-Herz-Durchströmung, die in den hier dargestellten Schlachtbetrieben verwendet wurde, nicht immer zum Herzkammerflimmern geführt hatte. Die Anzahl der Reaktionen der Schweine auf das heiße Wasser war begrenzt. 92 % der Schweine, die den Kopf während der Reizapplikation geschüttelt hatten und 78 % derer, die eine aufrichtende Bewegung gezeigt hatten, wiesen mindestens einen positiven Gehirnnerven-Befund auf. Auffälligkeiten in den Vordergliedmaßen korrelierten zu 59 % und das Muster “Maul öffnen” zu 52 % mit positiven Gehirnnerven-Befunden. Bewegungen aus dem Becken bzw. den Hintergliedmaße heraus waren nur zu 21 % mit positiven Gehirnnerven-Befunden verbunden. Bei der Betrachtung der Bewegungsmusterkombinationen stellte die Autorin fest, dass nahezu keine Reaktion missachtet werden sollte. Lediglich das Muster „ausschließliche Bewegungen Becken/Hintergliedmaße“ korrelierte in keinem der 59 Fälle mit positiven Gehirnnerven-Befunden. Dieses Ergebnis deckt sich mit den Aussagen von GRANDIN (2013) und den Mitarbeitern des bsi Schwarzenbek (ANON. 2013a), die darauf hinwiesen, dass der caudale Körperabschnitt elektrisch betäubter Schlachtschweine zur Einschätzung ihres möglicherweise vorhandenen Bewusstseins keine Relevanz besitzt. Während der Untersuchungen wurden außerdem Spontanbewegungen der Schlachtschweine zwischen dem Stechen und dem Heißwasser-Test analysiert. Jedes Tier, das eine Reaktion auf die Heißwasser-Reiz-Applikation zeigte und mindestens einen positiven Befund in der Gehirnnerven-Untersuchung aufwies, hatte vorher das Spontanbewegungsmuster „Maul öffnen“ durchgeführt. Um dem Überwachungs- und Schlachthofpersonal zu vermitteln, welche Spontan-bewegungsmuster bzw. reizinduzierten Reaktionen bei der Beobachtung der Nachentblutestrecke entscheidend sind, wurden entsprechende Arbeitsanweisungen entwickelt. Bereits vorhandene Literatur wurde hierbei mit eingearbeitet (ANIL 1991, ATKINSON et al. 2012 und EFSA 2013). Als eine wirksame Lösung um den sicheren Tod von Schweinen vor weiteren Schlachtarbeiten sicherzustellen, scheint es sinnvoll entsprechende Spontanbewegungen zu beachten und die Implementierung einer abschließenden Untersuchung mittels eines Heißwasser-Reiz-Tests am Ende der Nachentblutestrecke zu verwirklichen. Selbstverständlich sollten weiterhin die Betäubung und Entblutung der Tiere möglichst sicher kontrolliert werden. Für die Nachbetäubung bzw. Tötung der betroffenen Schweine wird der Einsatz eines Bolzenschussgerätes von der EFSA (2004), dem bsi Schwarzenbek und dem Max Rubner-Institut empfohlen
Modern slaughter regimes carry a risk of live animals being further processed (SCHÜTTE and BOSTELMANN 2001, TROEGER 2005 and TROEGER and MEILER 2006). This serious animal welfare problem may result from inefficient stunning and/or lack of complete and fast exsanguination of the pigs. In 2009, the European Commission implemented Council Regulation (EC) No. 1099/2009 on the protection of animals at the time of killing (ANON. 2009). The study lays groundwork for developing an automated method to verify the absence of signs of life in slaughter pigs. The hypothesis is that pigs that react to a painful stimulus, like hot water, several minutes after debleeding have the risk of a partly functional brains. The study took place at three commercial abattoirs in Germany using different electrical stunning (head-to-body) and bleeding methods. In the main part of the study a total of 5,301 finishing pigs was examined and videotaped on line. As a stimulus to check the absence of signs of life right before further processing, namely four to five minutes after sticking, a hot-water-stimulus at 65 °C was utilized. The residence time of the stimulus amounted either five or 15 seconds. An automated construction, built by the company BANSS Schlacht- und Fördertechnik GmbH (Biedenkopf/Germany), implemented the stimulus mainly within the faces of the pigs. As a reference to the observation of movements during the stimulation, brain stem reflexes (corneal and palpebral) and reactions to a nasal septum pinch were clinically examined. Pigs with any positive result were restunned or killed using a captive bolt device. The sensitivity of the hot-water-test was determined at 99 %. One out of 75 animals exhibited positive corneal- and palpebral-reflexes although this one pig did not show any reaction to the hot water stimulation. However, obvious spontaneous movements of this animal could be observed beforehand. The specificity of the hot-water-test was determined at 98 %. Almost every pig with negative brain stem results remained motionless during the stimulation. A share of 3.8 % (n = 199) of pigs showed movements during the hot water exposure. Es war kein Unterschied zwischen dem fünf bzw. 15 Sekunden anhaltendem Reiz zu ermitteln. No difference was estimated between the residence times of five versus 15 seconds. Besides inefficient bleeding one possible reason for this result is reversible stunning. Electrical stunning is reversible, unless effective cardiac arrest is caused (HOENDERKEN et al. 1980 and VOGEL et al. 2010). It may be assumed that after head-to-body electrical stunning used by the abattoirs displayed in this study cardiac arrest was not always achieved. The number of individual responses was limited. 92 % of pigs that shook their heads during the stimulation and 78 % that showed a righting reflex exhibited at least one positive brain stem result. Noticeable front leg activity correlated to 59 % and the movement “opening of the mouth” to 52 % with positive brain stem results. Hips or hind leg movements were only associated with positive brain stem results in 21 % of the cases. By looking at the combinations of movements the author found that nearly no reaction should be ignored. Merely exclusive hips or hind leg movements in none of the 59 cases correlated with brain stem results. This finding is supported by the statements made by GRANDIN (2013) and the staff of the bsi Schwarzenbek (ANON. 2013a), pointing out that the caudal body part of electrically stunned slaughter pigs possesses no relevance to evaluating possible consciousness. During the study additionally spontaneous movements of the slaughter pigs were analyzed between sticking and the hot water device. Every animal that eventually showed a reaction to the hot water stimulation and exhibited at least one positive result during the brain stem examination had shown spontaneous mouth opening. Appropriate working instructions for the monitoring personnel and the slaughter staff, in order for them to realize which spontaneous movements or stimulus induced reactions during the observations of the debleeding line are relevant, were designed. For this available expertise has additionally been taken into account (ANIL 1991, ATKINSON et al. 2012 and EFSA 2013). As a suitable solution for ascertaining death before further processing, the idea of paying attention to slaughter pigs that obviously show signs of recovery and the implementation of a “last check” by using a hot water test right before further processing seems reasonable. Of course the stunning and exsanguination should still be safely monitored. The use of a captive bolt device to restun or kill “suspicious” pigs is recommended by the EFSA (2004), the bsi Schwarzenbek and the Max Rubner-Institute

Dissertação de Mestrago Integrado em Medicina Veterinária
A etapa do abate é um dos pontos críticos na gestão da piscicultura, ao induzir stress nos peixes, o que não só afeta o bem-estar animal, como também a qualidade do produto final. No decorrer das investigações relativas à neuroanatomia e neurofisiologia dos peixes, é cada vez mais aceite que, tal como os mamíferos e aves, os peixes também são animais sencientes. Contudo, não são abrangidos pelo regulamento relativo à proteção dos animais no abate. Como tal, a etapa do abate de peixes acaba por ser negligenciada, ao ter pouca ou nenhuma consideração pelo bem-estar animal. O principal objetivo desta dissertação é dar uma visão integrada dos efeitos de diferentes métodos de atordoamento e abate na corvina (Argyrosomus regius), um peixe teleósteo da família Sciaenidae, com crescente utilização na aquacultura. Os métodos estudados foram asfixia por exposição ao ar, termonarcose, eletronarcose, secção medular e iki jime. Foi avaliada a influência destes métodos nas componentes bem-estar animal e qualidade. No que se refere ao bem-estar animal, procedeu-se à avaliação da insensibilização e da resposta fisiológica ao stress, quanto à qualidade foi avaliada a evolução do músculo post mortem (rigor mortis) em associação com a avaliação sensorial do grau frescura. Os resultados revelaram que, o método japonês iki jime foi o único a induzir insensibilização imediata que, por sua vez, apresentou a resposta ao stress mais discreta e melhores resultados em termos de qualidade. Também foi possível apoiar a tese de que a asfixia por exposição ao ar não é uma prática ética, ao induzir uma resposta ao stress grave, o que demonstrou afetar de forma negativa a qualidade, ao acelerar o desenvolvimento do rigor mortis e, por sua vez, a deterioração do músculo. Como complementaridade ao estudo anterior, foi realizado um inquérito por questionário, com o objetivo de avaliar a perceção do consumidor sobre o abate de peixes. Os resultados revelaram que, existe um forte desconhecimento acerca deste domínio, sobretudo no que se refere aos métodos de atordoamento e abate alternativos ao método praticado na pesca tradicional (asfixia por exposição ao ar). Contudo, os resultados revelaram também que, o método de abate a que o peixe for submetido pode influenciar a atitude do cidadão enquanto consumidor, o que pode representar um impacto no mercado. O reforço desta preocupação com o bem-estar dos peixes no abate, para além de promover a adoção de práticas mais éticas, também contribui para melhorar a qualidade, e assim, satisfazer as necessidades das caraterísticas intrínseca e extrínsecas do produto, exigidas por parte do consumidor.
ABSTRACT - Slaughter of meagre (Argyrosomus regius): what is the method that minimizes stress and maximizes quality? The slaughter is one of the important steps in fish farming management, it causes stress on animals and consequently reduces animal welfare as well as the quality of the product. In the course of investigations into the neuroanatomy and neurophysiology of fish, it is becoming more accepted, that like mammals and birds, fish are also sentient animals. However, they are not embraced by animal rights regulations. Therefore, the stage of fish slaughter ends up being neglected, with no consideration for the animal welfare. The main objective of this dissertation is to provide an evaluation of the effects of different stunning and slaughter methods in meagre (Argyrosomus regius), a teleost fish of the Sciaenidae family, with increasing exploration in aquaculture. The methods studied were: asphyxiation by air exposure, thermonarcosis, electronarcosis, medullary section and iki jime. The influence of these methods on animal welfare and quality components was evaluated. With regard to animal welfare, the sensitization and physiological response to stress were evaluated. The quality of the post mortem muscle (rigor mortis) evolution was evaluated in association with the sensory evaluation of the freshness degree. The results showed that the Japanese, iki jime, method was the only one that induced immediate insensitivity, which in turn had a lower stress response and better quality. It was also possible to concluded that asphyxiation by air exposure is not an ethic practice, causing high levels of stress, which negatively affects meat quality by accelerating the process of fish deterioration. As a complement to the previous study, a survey was conducted to assess fish slaughter awareness by fish consumers. The results revealed that fish slaughter is still a fairly unknown subject, especially regarding the alternative methods to the traditional method (asphyxiation by air exposure). However, it revealed that consumers preference can be influence, when they are aware of the different slaughter methods, which can have an impact on the market. Using slaughter methods that take animal welfare in account, will not only reduce the animal stress but also improve fish quality, and thus meeting the needs of the intrinsic and extrinsic characteristics of the product by the consumer.
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The objective of the present study was to verify the application of eletronarcosis in Nile tilapias (Oreochromis niloticus), to obtain a humanitary slaughter and a higher stunning time, keeping the steak characteristics. It was tested the tima of exposition (5, 10, 20 and 30 seconds s) of the fish in different electric currents (1,5 3,0, 4,5 and 6,0 Amperes A) and in two tipes of tension (Alternating current AC and Direct current DC). For this, a total of 184 copies of tilapia weighting 247,08 ± 37,04g and length of 23,93 ± 1,09cm were used. In the first study it was used 128 fish, that were individually stunned, using a tension regulator (VARIAC), in which was connected two aluminum electrodes, that stayed immersed in a plastic box with water and the pre-determined time of exposition were controlled in a manual way. All the fish were filmed and later it was verified through the videos how much time each individual to return the behavioral reflexes (Opercular Rate OR, Swimming SW and Balance BA). The second study analyzed variables corresponding to the cold steak quality, using the quality index method (QIM) and the pH in each 72 hours for 36 days, and the steak color was measured only on day 0. The steaks were obtained from tilapias stunned by eletronarcosis (AC 3 and 6A and DC 3A, with time of exposition of the fish for 30s) and ice was the control method. It was verified significant differences (p < 0,05) in both studies, being the higher stunning time with the use of AC from 3 to 6A for 30s where the final return of spontaneous behaviors was from 179 to 360s to the BA, the OR was the first to be manifested after the stunning, with the time of returning from 37 to 46s and between this there was the swimming return, with time from 140 to 154s. For the analyzed variables of the steak, it was obtained influence on pH due to the interaction time*treatment, which grew over the days of analysis, and reaching level of rejection from day 15, as well as the scores of quality index (QI) parameters, in this it was verified high correlation between the time of storage and QI, with R² between 0,94 and 0,96, but with medium QI different (p < 0,05) to AC 6A. And color did not differ (p < 0,05) between the stunning methods, showing that the eletronarcosis can be applied, using AC from 3 to 6A for 30s, and having time to perform euthanasia between 37 and 46s.
O objetivo do presente estudo foi verificar a aplicação da eletronarcose em tilápias do Nilo (Oreochromis niloticus), para a obtenção de um abate humanitário e o maior tempo de insensibilização possível, mantendo as características do filé. Foram testados o tempo de exposição (5, 10, 20 e 30 segundos s) dos peixes em diferentes correntes elétricas (1,5, 3,0, 4,5 e 6,0 Amperes - A) e em dois tipos de tensão (Corrente Alternada CA e Corrente Contínua CC). Para isso um total de 184 exemplares de tilápia com peso de 247,08 ± 37,04 g e comprimento de 23,93 ± 1,09 cm foram utilizados. No primeiro estudo utilizou-se 128 peixes, que foram insensibilizados individualmente, utilizando um regulador de tensão (VARIAC), no qual estava ligado dois eletrodos de alumínio, que ficaram imersos em uma caixa plástica contendo água, e os tempos de exposição pré-determinados foram controlados de forma manual. Todos os peixes foram filmados e posteriormente verificou-se através dos vídeos quanto tempo cada indivíduo levou para o retorno dos reflexos comportamentais (Batimento Opercular BO, Natação NA e Equilíbrio EQ). Já o segundo estudo analisou variáveis correspondentes a qualidade do filé resfriado, utilizando o método de índice de qualidade (MIQ) e o pH a cada 72 horas por 36 dias, e a coloração do filé foi medida somente no dia 0. Os filés foram obtidos de tilápias insensibilizadas por eletronarcose (CA 3 e 6 A e CC 3 A, com tempos de exposição dos peixes por 30 s) e gelo que foi o método controle. Foram verificadas diferenças significativas (p < 0,05) nos dois estudos, sendo que o maior tempo de insensibilização foi com a utilização da CA de 3 a 6 A por 30 s onde o tempo de retorno dos comportamentos espontâneos final foi de 179 a 360 s para o EQ, já o BO foi o primeiro a ser manifestado após a insensibilização, com tempo de retorno de 37 a 46 s e nesse meio houve o retorno da natação, com tempos de 140 a 154 s. Para as variáveis analisadas do filé, obteve-se influencia no pH devido a interação tempo*tratamento, o qual aumentou com o decorrer dos dias de análise, e atingindo nível de rejeição a partir do dia 15, assim como as pontuações dos parâmetros do índice de qualidade (IQ), nesse verificou-se alta correlação entre tempo de armazenamento e IQ, com R2 entre 0,94 e 0,96, mas com IQ médio diferente (p < 0,05) para CA 6 A. Com a relação a coloração não diferiu (p > 0,05) entre os métodos de insensibilização, mostrando que a eletronarcose pode ser aplicada, utilizando CA de 3 a 6 A por 30 s, e tendo tempo para realizar a eutanásia entre 37 e 46 s.

Slaughter by ventral neck incision (VNI) is performed on some animals without prior stunning in New Zealand and other countries. A single incision with a razor sharp blade is made in the ventral aspect of the neck, sectioning both carotid arteries and jugular veins, though, not the vertebral arteries. There are a number of potential welfare concerns surrounding slaughter by VNI including pain due to the incision, which may lead to distress during the time before loss of consciousness. The aims of this thesis were to identify cortical responses indicative of noxious stimulation due to slaughter by VNI using analysis of the electroencephalogram (EEG) power spectrum and to investigate the effects of non-penetrative captive bolt (NPCB) stunning on these cortical responses. The studies utilised adaptations of a minimal anaesthesia model, which has been validated in a range of mammalian species. Surgical dehorning was used as a validation technique for this methodology in cattle and demonstrated a ‘typical’ EEG response to noxious stimulation. Cattle slaughtered by VNI without prior stunning produced specific responses in the EEG that strongly indicated responses to noxious stimulation. Causation was investigated in cattle where blood flow through the brain remained intact during neck tissue incision (NTI) or the major blood vessels of the neck were isolated and transected independently of other neck tissues (BVT). The response to neck incision in intact animals was principally due to the noxious sensory input due to incision of neck tissues and not mainly as a result of loss of blood flow through the brain. NPCB stunning produced states of cortical activity that were incompatible with the maintenance of sensibility and pain perception. Experimental examination of the time to onset of undoubted insensibility was attempted in cattle subsequent to a pilot study in sheep. The generation of somatosensory-evoked potentials was problematic in cattle. The conclusions of this thesis are that incision of neck tissues during slaughter without prior stunning constitutes a substantial noxious stimulus. Were an animal conscious, this stimulus would be perceived as painful until the onset of hypoxiainduced insensibility. This would represent a significant compromise to animal welfare.

Einleitung Entsprechend der Tierschutz-Schlachtverordnung sind Wirbeltiere vor der Tötung grundsätzlich zu betäuben. Die für Fische zulässigen Betäubungsmethoden haben sich jedoch für die Betäubung Afrikanischer Welse (Clarias gariepinus) in der Praxis als problematisch erwiesen. Ziel der Untersuchungen Das Untersuchungsziel bestand in der Erprobung und Optimierung von Betäubungsverfahren für die Schlachtung Afrikanischer Welse. Verschiedene Varianten der Vorkühlung, Eiswasserbehandlung und Elektrobetäubung wurden einzeln oder in Kombination vergleichend geprüft. Materialien und Methoden Zur Beurteilung der Betäubungswirkung dienten klinische Tests: Atmung, Schwimmbewegungen, Reaktion auf Manipulation, Gleichgewicht mit und ohne Manipulation, Augendrehreflex, Schmerzreiz. Weiterhin erfolgten Blutuntersuchungen mit Bestimmung der Cortisol-, Glukose-, Laktat-, Natrium-, Kalium- und Chloridgehalte zur Beurteilung der Stressbelastung der Welse. Insgesamt wurden 378 Afrikanische Welse genutzt. Die Untersuchungen umfassten sechs Teilversuche: Im Vorversuch 0 fand die Prüfung der Untersuchungsmethoden statt. Versuch 1a diente dem Vergleich von drei Varianten der Eiswasserbehandlung: Variante 1: Eiswasser mit +0,1 ± 0,2 °C, Variante 2: Eiswasser mit zusätzlichem Crash-Eis bei gleicher Temperatur und Variante 3: Eiswasser mit Kochsalz bei -2,0 ± 0,5 °C. Im Versuch 1b wurden drei Vorkühltemperaturen getestet: 10 °C, 15 °C und 20 °C. Die Elektrobetäubung (Versuch 2 bzw. Versuche 3 und 4 als Kombinationsmethoden) erfolgte am Einzeltier per Kopfdurchströmung mit 250 bzw. 300 V und 1,3 bzw. 1,8 A Wechselstrom. Bei der Prüfung der Kombination von Elektrobetäubung und Eiswasserbehandlung wurden die Welse nach der Kopfdurchströmung unmittelbar in ein mit Eiswasser gefülltes Becken umgesetzt. Versuch 4 diente der Überprüfung der Kombinationsmethode auf Praxistauglichkeit in einer Kreislaufanlage an 50 schlachtreifen Welsen. Ergebnisse Die maximalen Reaktionszeiten im Eiswasser lagen in den drei Varianten des Versuches 1a zwischen 3,8 und 4,7 Minuten (arithmetische Mittel). Die Eiswasserbehandlung ermöglichte kein schnelles Erreichen der Wahrnehmungs- und Empfindungslosigkeit. Die Variante 1 – Eiswasser mit +0,1 ± 0,2 °C – war mit den geringsten Belastungen verbunden. Gleiches trifft auf die Vorkühltemperatur von 15 °C zu. Mittels elektrischer Kopfdurchströmung wurde im Versuch 2 eine Betäubung der Welse erreicht, verbunden mit einer 30 bis 60 Sekunden andauernden Wahrnehmungslosigkeit. Die Betäubung geschah am Einzeltier nach vorheriger Separierung. In den Kombinationsversuchen 3 und 4 wurde kein durchgängiger Zustand der Wahrnehmungs- und Empfindungslosigkeit beobachtet. Die Welse zeigten im Mittel 2,7 bzw. 3,3 Minuten nach Umsetzen in das Eiswasser zuletzt Reaktionen auf klinische Tests. Schlussfolgerungen Die Eiswasserbehandlung ermöglicht keine tierschutzgerechte Betäubung entsprechend der Tierschutz-Schlachtverordnung. Eine Vorkühlung vor der Betäubung scheint notwendig. Vor der Elektrobetäubung schränkt sie die Beweglichkeit der Welse ein und ermöglicht somit ein besseres Ansetzen der Elektroden. Die Einzeltierbetäubung ist zeitaufwendig und setzt von der durchführenden Person ausreichend Erfahrung voraus, um Fehlbetäubungen zu vermeiden. Die kurze Wahrnehmungslosigkeit erfordert eine sich unmittelbar anschließende Entblutung bzw. Dekapitation. Für kleine Schlachtzahlen bzw. als Alternative zur Betäubung per Kopfschlag erscheint die untersuchte Methode mit der verwendeten gerätetechnischen Ausstattung bzw. unter Beachtung der elektrischen Betäubungsparameter geeignet. Zur Validierung der Kombination von Vorkühlung, Elektrobetäubung und Eiswasserbehandlung sind weitere Untersuchungen erforderlich. Es ist zu prüfen, ob durch eine Veränderung der Betäubungsparameter eine bis zum Tod anhaltende Wahrnehmungs- und Empfindungslosigkeit gewährleistet werden kann.

Se estudió la influencia de la tecnología del sacrificio sobre la calidad de la canal y la carne porcinas. El trabajo consistió en estudiar minuciosamente todas las operaciones llevadas a cabo en un matadero industrial de gran capacidad, desde la recepción de los cerdos, hasta la obtención de la canal refrigerada, con el objeto de detectar y, en su caso, subsanar, posibles pérdidas de calidad que pudieran ser atribuibles a la tecnología empleada. Para ello, se valoró la importancia de aquellas operaciones que podrían jugar un papel relevante en la consecución de una mejor calidad, incluido el diseño de instalaciones, tales como zonas de descarga, corrales, salas de sacrificio y faenado y cámaras frigoríficas. El estudio fue realizado sobre 2047 cerdos de cebo procedentes de 36 granjas, realizando diferentes medidas y ensayos según las operaciones estudiadas. Se determinó el peso, magro y panículo adiposo de la canal, estableciéndose su clase comercial y conformación subjetiva. La temperatura de la canal fue estudiada en el músculo SM a 3 niveles de profundidad (superficial, medio y profundo) a 45 min, 2 y 24 h. pm. La calidad de la carne fue estimada en el músculo SM a partir de medidas de pH (45 min, 2, 8 y 24 h) y CE (45 min, 2 y 24 h). Las carnes fueron clasificadas como PSE (CE2>8 mS/cm), DFD (pH86,2) y Normales cuando la CE2<6 mS/ cm y el pH8<6. Los resultados obtenidos muestran como la calidad de la carne va a estar condicionada por el manejo presacrificio, la refrigeración de las canales, y en menor medida, por el faenado. Especialmente críticos son el reposo, acarreo y aturdido, como las operaciones más influyentes en vida del animal, junto con los ritmos de sacrificio que puedan sobrepasar la capacidad frigorífica del sistema de oreo rápido. También se encontraron mermas en la calidad de la carne como consecuencia del diseño y ubicación inadecuadas de algunas instalaciones o equipos.
The influence of the slaughter technology on carcass and pork meat quality was studied. The work consisted in a throughout study including all the operations carried out in a great capacity industrial slaughter, from the arrival of the animals to the refrigerated carcass. This was made in order to detect and correcting possible quality losses related to the technology applied. For this purpose, it was considered the most important processes that could have influence on the meat quality, among them were included: installation design, loading areas, corrals, slaughtering rooms, and refrigeration rooms. 2047 pigs from 36 different farms were studied considering different batches and measurements according to the industrial stage under study. Weight, lean, and backfat of carcass were determined in order to establish their commercial type and subjective conformation. SM temperature at 45 min. 2 and 24 h pm was measured at three different deep levels (surface, middle, bottom). pH (45min. 2,8,and 24h pm and CE (45min, 2, and 24h pro) measurements at SM were used for the estimation of meat quality. Meat was classified according to the latest parameters as PSE (CE2>8 mS/cm), DFD (PH8>6.2), and normal (CE2<6mS/cm and pH8<6). The results obtained showed the relationship between antemortem handling, carcass refrigeration conditions, and slaughter handling with meat quality. The most critical parameters affecting meat quality can be considered: resting animal, entry of animals into the slaughter rooms, stunning, and finally refrigeration room capacity being enough to keep the slaughtering rate. Losses of meat quality were also found because of non-adequate design and location of the installations.

This thesis describes experimental work conducted to define factors associated with the occurrence of ecchymosis (blood splash) in fallow deer, and discusses facets of the Australian venison processing sector with respect to its capacity to improve the quality of venison. Data was collected on 1804 deer slaughtered experimentally (n equals 494) or at commercial works (n equals 1310) in a range of different slaughter systems. The study showed that a number of factors contribute to the expression of ecchymosis in the carcases of slaughtered deer, and the tailoring of slaughter procedures to suit particular slaughter systems is likely to reduce the extent to which ecchymosis occurs.