O objetivo deste trabalho foi investigar a incidência de carnes DFD (dark, firm, dry) em um frigorífico comercial de frango e determinar as suas propriedades funcionais comparando com as do PSE (pale, soft, exudative) e Normal em filés de peito, Pectoralis major. Para a avaliação da ocorrência desses tipos de cores, as aves das linhagens Cobb e Ross receberam banho calmante, com aspersão de água em temperatura ambiente por aproximadamente 10 minutos, associado à ventilação, imediatamente antes do seu abate. Em seguida, foram sacrificadas e desossadas e os filés foram analisados ao tempo de 90min e 24h post mortem, para coleta de valores de pH e L* e classificados em carnes PSE, Normal e DFD, com base nos resultados de 24h post mortem (n=329). O resultado da incidência foi de 24,92, 73,55 e 1,52% para amostras PSE, Normal e DFD, respectivamente. O valor de L* ao tempo de 90 min post mortem foi de 51,57 (&#177;1,91), 48,55 (&#177;1,94) e 41,67 (&#177;1,80), respectivamente, enquanto para o pH foi de 6,10 (&#177;0,48), 6,31 (&#177;0,59) e 7,15 (&#177;0,43) para carnes PSE, Normal e DFD, respectivamente. Após 24h post-mortem os resultados foram para L* 54,32 (&#177;1,09), 50,56 (&#177;1,64), 42,23 (&#177;1,80) e para o pH 5,69 (&#177;0,14), 5,78 (&#177;0,14), 6,05 (&#177;0,43) respectivamente para amostras PSE, Normal e DFD, significativamente diferente (P<0,05). Para o estudo das propriedades funcionais, amostras (n=374) foram selecionadas nas linhas de produção, classificadas em carnes PSE, Normal e DFD de acordo com o L* e pH 24h post mortem. Foram realizadas as medidas do exsudado formado, perda de umidade durante o cozimento e estabilidade da emulsão. Os resultados encontrados na medida do exsudado foram 4,73 (&#177;2,61)%, ,55 (&#177;2,16)%, 1,11 (&#177;1,01)% para PSE, Normal e DFD respectivamente, significativamente diferentes (P<0,05). A medida da perda de umidade durante o cozimento para as amostras PSE foi de 26,03 (&#177;2,93)%, para o grupo Normal a quebra foi de 25,38 (&#177;3,96)% e para o grupo DFD 22,89 (&#177;2,65)%. Entre as amostras dos grupos PSE e Normal não ocorreu diferença significativa (P<0,05), apesar da leve tendência para menor quebra de peso para grupo considerado Normal, enquanto que a quebra de peso para o grupo Normal e DFD apresentou resultados significativamente diferentes (P<0,05) com diferença significativa de 2,50% para DFD. Finalmente, para a medida de instabilidade da emulsão os resultados foram 1,04 (&#177;0,32)%, 0,78 (&#177;0,20)%, 0,70 (&#177;0,12)%, respectivamente para PSE, Normal e DFD, significativamente diferente (P<0,05). Concluindo, as matérias-primas que apresentam características DFD tendem a conferir melhor qualidade funcional com melhor capacidade de absorção, retenção de umidade, baixo exsudado e baixa perda durante o cozimento. A constatação da diferença nas cores do filé na linha de processamento pode padronizar os processos contribuindo para a distribuição adequada das amostras de carne PSE, Normal e DFD especificamente para diferentes tipos de processamento trazendo benefícios econômicos às industrias e qualidade sensorial aos consumidores. / The objective of this work was to investigate the incidence of DFD (dark, firm, dry) meat, in a commercial chicken plant and to determine its functional properties in comparison to PSE (pale, soft, exudative) and Normal breast fillet, Pectoralis major. In order to evaluate the occurrence of different color types, commercial Cobb and Ross chickens were submitted to water shower and ventilation treatments during 10 minutes immediately before slaughtering. Birds (n=329) were sacrificed, deboned and analyzed after 90 minutes and 24h post mortem for pH and L* values evaluation and submitted to classification as PSE, Normal, DFD meat based upon 24h post mortem samples. The occurrence was 24.92, 73.55 and 1,52% for samples PSE, Normal and DFD meats, respectively. L* values for 90 minutes post mortem were 51.57 (&#177;1.91), 48.55 (&#177;1.94) and 41.67 (&#177;1.80), respectively, while for pH values were 6.10 (&#177;0.48), 6.31 (&#177;0.59) and 7.15 (&#177;0.43) for PSE, Normal e DFD meats, respectively. After 24h post-mortem, L* values results were 54.32 (&#177;1.09), 50.56 (&#177;1.64), 42.23 (&#177;1.80) for PSE, Normal and DFD meats, respectively, and pH values were 5.69 (&#177;0.14), 5.78 (&#177;0.14), 6.05 (&#177;0.43) respectively for PSE, Normal and DFD meats. All results were significantly different (P<0.05). For functional properties evaluation, samples (n=374) were selected from production lines and ranked as PSE, Normal e DFD meats according to L* and pH 24h post mortem. Measurement for formed exudate, cook drip loss and emulsion stability was carried out. Results for formed exudate were 4.73 (&#177;2.61), 2.55 (&#177;2.16), 1.11 (&#177;1.01)% for PSE, Normal e DFD meats, respectively and for cook drip loss for PSE 26.03 (&#177;2.93), for Normal 25.38 (&#177;3.96) and for DFD 22.89 (&#177;2.65)%, respectively. No significantly difference (P<0,05) was found between PSE and Normal samples although there was a tendency for lower weight loss for normal group while between normal and DFD samples a significantly difference (P<0.05) was found. Finally, for emulsion estability results were 1.04 (&#177;0.32), 0.78 (&#177;0.20), 0.70 (&#177;0.12)%, respectively for PSE, Normal and DFD samples, significantly different (P<0,05). In conclusion, broiler breast fillet meat which presents DFD characteristics tends to have better functional properties for water holding capacity, lower exudate formation and lower cook drip loss. The standardization of colour differences detection in broiler fillet meat in the processing line could direct these samples specifically to PSE, normal and DFD meats for processing meat products accordingly in order to have economical benefits to the poultry industries and particularly sensorial meat products improvement for consumers.

O objetivo deste trabalho foi investigar a incidência de carnes DFD (dark, firm, dry) em um frigorífico comercial de frango e determinar as suas propriedades funcionais comparando com as do PSE (pale, soft, exudative) e Normal em filés de peito, Pectoralis major. Para a avaliação da ocorrência desses tipos de cores, as aves das linhagens Cobb e Ross receberam banho calmante, com aspersão de água em temperatura ambiente por aproximadamente 10 minutos, associado à ventilação, imediatamente antes do seu abate. Em seguida, foram sacrificadas e desossadas e os filés foram analisados ao tempo de 90min e 24h post mortem, para coleta de valores de pH e L* e classificados em carnes PSE, Normal e DFD, com base nos resultados de 24h post mortem (n=329). O resultado da incidência foi de 24,92, 73,55 e 1,52% para amostras PSE, Normal e DFD, respectivamente. O valor de L* ao tempo de 90 min post mortem foi de 51,57 (&#177;1,91), 48,55 (&#177;1,94) e 41,67 (&#177;1,80), respectivamente, enquanto para o pH foi de 6,10 (&#177;0,48), 6,31 (&#177;0,59) e 7,15 (&#177;0,43) para carnes PSE, Normal e DFD, respectivamente. Após 24h post-mortem os resultados foram para L* 54,32 (&#177;1,09), 50,56 (&#177;1,64), 42,23 (&#177;1,80) e para o pH 5,69 (&#177;0,14), 5,78 (&#177;0,14), 6,05 (&#177;0,43) respectivamente para amostras PSE, Normal e DFD, significativamente diferente (P<0,05). Para o estudo das propriedades funcionais, amostras (n=374) foram selecionadas nas linhas de produção, classificadas em carnes PSE, Normal e DFD de acordo com o L* e pH 24h post mortem. Foram realizadas as medidas do exsudado formado, perda de umidade durante o cozimento e estabilidade da emulsão. Os resultados encontrados na medida do exsudado foram 4,73 (&#177;2,61)%, ,55 (&#177;2,16)%, 1,11 (&#177;1,01)% para PSE, Normal e DFD respectivamente, significativamente diferentes (P<0,05). A medida da perda de umidade durante o cozimento para as amostras PSE foi de 26,03 (&#177;2,93)%, para o grupo Normal a quebra foi de 25,38 (&#177;3,96)% e para o grupo DFD 22,89 (&#177;2,65)%. Entre as amostras dos grupos PSE e Normal não ocorreu diferença significativa (P<0,05), apesar da leve tendência para menor quebra de peso para grupo considerado Normal, enquanto que a quebra de peso para o grupo Normal e DFD apresentou resultados significativamente diferentes (P<0,05) com diferença significativa de 2,50% para DFD. Finalmente, para a medida de instabilidade da emulsão os resultados foram 1,04 (&#177;0,32)%, 0,78 (&#177;0,20)%, 0,70 (&#177;0,12)%, respectivamente para PSE, Normal e DFD, significativamente diferente (P<0,05). Concluindo, as matérias-primas que apresentam características DFD tendem a conferir melhor qualidade funcional com melhor capacidade de absorção, retenção de umidade, baixo exsudado e baixa perda durante o cozimento. A constatação da diferença nas cores do filé na linha de processamento pode padronizar os processos contribuindo para a distribuição adequada das amostras de carne PSE, Normal e DFD especificamente para diferentes tipos de processamento trazendo benefícios econômicos às industrias e qualidade sensorial aos consumidores. / The objective of this work was to investigate the incidence of DFD (dark, firm, dry) meat, in a commercial chicken plant and to determine its functional properties in comparison to PSE (pale, soft, exudative) and Normal breast fillet, Pectoralis major. In order to evaluate the occurrence of different color types, commercial Cobb and Ross chickens were submitted to water shower and ventilation treatments during 10 minutes immediately before slaughtering. Birds (n=329) were sacrificed, deboned and analyzed after 90 minutes and 24h post mortem for pH and L* values evaluation and submitted to classification as PSE, Normal, DFD meat based upon 24h post mortem samples. The occurrence was 24.92, 73.55 and 1,52% for samples PSE, Normal and DFD meats, respectively. L* values for 90 minutes post mortem were 51.57 (&#177;1.91), 48.55 (&#177;1.94) and 41.67 (&#177;1.80), respectively, while for pH values were 6.10 (&#177;0.48), 6.31 (&#177;0.59) and 7.15 (&#177;0.43) for PSE, Normal e DFD meats, respectively. After 24h post-mortem, L* values results were 54.32 (&#177;1.09), 50.56 (&#177;1.64), 42.23 (&#177;1.80) for PSE, Normal and DFD meats, respectively, and pH values were 5.69 (&#177;0.14), 5.78 (&#177;0.14), 6.05 (&#177;0.43) respectively for PSE, Normal and DFD meats. All results were significantly different (P<0.05). For functional properties evaluation, samples (n=374) were selected from production lines and ranked as PSE, Normal e DFD meats according to L* and pH 24h post mortem. Measurement for formed exudate, cook drip loss and emulsion stability was carried out. Results for formed exudate were 4.73 (&#177;2.61), 2.55 (&#177;2.16), 1.11 (&#177;1.01)% for PSE, Normal e DFD meats, respectively and for cook drip loss for PSE 26.03 (&#177;2.93), for Normal 25.38 (&#177;3.96) and for DFD 22.89 (&#177;2.65)%, respectively. No significantly difference (P<0,05) was found between PSE and Normal samples although there was a tendency for lower weight loss for normal group while between normal and DFD samples a significantly difference (P<0.05) was found. Finally, for emulsion estability results were 1.04 (&#177;0.32), 0.78 (&#177;0.20), 0.70 (&#177;0.12)%, respectively for PSE, Normal and DFD samples, significantly different (P<0,05). In conclusion, broiler breast fillet meat which presents DFD characteristics tends to have better functional properties for water holding capacity, lower exudate formation and lower cook drip loss. The standardization of colour differences detection in broiler fillet meat in the processing line could direct these samples specifically to PSE, normal and DFD meats for processing meat products accordingly in order to have economical benefits to the poultry industries and particularly sensorial meat products improvement for consumers.

Experiments were conducted to determine the effects of nutrition, temperature during feed withdrawal, shackling duration, sex and age at processing on broiler quality. Low energy (94% of recommended) diets resulted in a lower percentage of carcass fat while increasing the percentage of carcass protein. Low protein (85% of recommended) resulted in a decreased percentage of carcass protein while carcass fat increased. Low protein diets also limited frame size as measured by length and width of P. major. Exposure to 9 C temperatures during feed withdrawal resulted in improved meat quality as measured by higher ultimate pH, lower drip loss and darker color. Long shackling time (120 s) did not affect ultimate pH, drip or cooking losses compared to short shackling (<10 s); however, short shackled broilers exhibited poorer tenderness values. Males had higher carcass protein and lower fat than females. Females exhibited higher ultimate pH, higher drip loss and lighter breast meat. Drip loss and ultimate pH decreased with age. Processing age and sex of broilers may have greater influences on meat quality than previously reported. / Animal Science

No description available.

The main objective of this thesis was to study (i) the effect of the fasting and lairage on carcass and technological meat quality and (ii) the inclusion of magnesium (MgCO3 and MgSO4) and/or tryptophan during 5 days before slaughtering pigs as a strategy to decrease stress levels and improve meat quality, with two different porcine RYR1 genotypes (NN and nn). An adequate combination of fasting and lairage period is recommended. A supplement of MgCO3 or Trp did not improve meat quality under minimal stressful ante mortem conditions; and MgSO4 had a laxative effect on pigs supplemented with it. When including nn pigs to the herd, it is recommended to consider the supplements’ combination of tryptophan and a source of Mg (avoiding MgSO4) to alleviate the negative effect of the stress and to improve technological meat quality. / L’objectiu principal d’aquest treball fou estudiar (i) l’efecte del dejuni i el temps d’espera a l’escorxador i (ii) l’efecte de l’addició de suplements de magnesi (MgCO3 o MgSO4) i/o triptòfan a la dieta durant els 5 dies previs al sacrifici com a estratègia per disminuir els nivells d’estrès i millorar la qualitat de la carn, en dos genotips porcins diferents respecte el gen RYR1 (NN i nn). Es recomana combinar correctament el dejuni i l’espera per millorar el benestar i la qualitat de la carn. El MgCO3 o el Trp no va millorar la qualitat de la carn en condicions de mínim estrès; i el MgSO4 provocà problemes digestius. En el cas d’optar per la utilització de genètiques nn, es recomana considerar la utilització de suplements de L-Trp amb fonts de magnesi (excloent el MgSO4) per pal•liar les conseqüències negatives de l’estrès i millorar la qualitat tecnològica de la carn.

Einleitung Der amtliche Tierarzt nimmt im europäischen Recht eine Schlüsselposition für den gesundheitlichen Verbraucherschutz und den Tierschutz von Schlachttieren ein. Zu Beginn der amtlichen fleisch-hygienischen Tätigkeit ist eine 200-stündige Pflichtassistenz vorgeschrieben. Gleichwohl wurde vor dem Hintergrund dieser verantwortungsvollen Tätigkeit die Wichtigkeit einer praktischen Ausbildung in der Schlachttier- und Fleischuntersuchung während des Veterinärmedizinstudiums sowohl rechtlich als auch durch verschiedene Organisationen hervorgehoben. In der Studienordnung nimmt das sogenannte „Schlachthofpraktikum“ mit 100 Stunden etwa ein Viertel der lebensmittelhygienischen Ausbildungszeit ein. Obligatorische Ziele dieses Lehrformats sind das Üben der amtlichen Ante- und Post-Mortem-Untersuchung bei den Tierarten Rind und Schwein, sowie das Informieren über die tierschutzgerechte Behandlung der Schlachttiere. In der Fachliteratur finden sich erste modellhafte, gleichwohl keine umfassenden Untersuchungen zum „Schlachthofpraktikum“ in Deutschland. Ziel der Untersuchung Daher widmet sich diese Dissertation einer tiefergehenden Untersuchung der praktischen Ausbildung in der Schlachttier- und Fleischuntersuchung. Hierbei sollten die studentischen Lernerfahrungen sowie die Meinungsbilder von Studierenden und amtlichen Tierärzten evaluiert und ausgewählte Situationen am Praktikumsschlachtbetrieb erhoben werden. Material und Methoden Im Rahmen einer Querschnittsstudie wurden zwei schriftliche, standardisierte Methoden (Evaluierung gemäß der Deutschen Veterinärmedizinischen Gesellschaft und eigene Erhebung) bei Leipziger Veterinärmedizinstudierenden der Abschlussjahrgänge 2008-2014 angewandt. Die Evaluierung umfasste eine Checkliste sowie je einen Bewertungsbogen für den Studierenden und den amtlichen Tierarzt. Die Erhebung kam aufgrund von Weiterentwicklungen in drei Versionen zur Anwendung. Ergebnisse Bei der Evaluierung gaben die 705 Studierenden an, zu 82,1 % (n=579) einen und zu 17,9 % (n=126) mehrere Praktikumsbetriebe besucht zu haben. Dabei wurden einige Betriebe mit zunehmender Häufigkeit benannt. Über 95,7 % (n=675) der Studierenden bestätigten die obligatorischen Praktikums-inhalte (Schlachttieruntersuchung: 95,7 %; n=674 / Fleischuntersuchung: 96,7 %; n=682 / Tierschutz-aspekte: 95,7 %; n=675). Die Fleischuntersuchung im Verdachtsfall markierten etwa drei Viertel der Teilnehmer (Rind: 69,4 %; n=489 / Schwein: 76,7 %; n=541). Viele Studierende gaben darüber hinaus weitere Themen an, wie bspw. Hygiene und Schlachttechnologie. Ein Abschlussgespräch notierten 79,4 % (n=559) der Praktikanten. Das Meinungsbild der Studierenden und amtlichen Tierärzte bzgl. des Praktikums fiel größtenteils positiv aus. 54,7 % (n=242) der amtlichen Tierärzte nahmen zudem an, die Studierenden für eine spätere fleischhygienische Tätigkeit motiviert zu haben; dem gegenüber gaben dies nur 31,1 % (n=138) der Studierenden an. Ausgewählte Situationen am Schlachtbetrieb wurden mithilfe der Erhebungen dokumentiert. Die Durchführung der Schlachttieruntersuchung beim Rind bzw. Schwein wurde in 97,6 % (n=249) resp. 96,1 % (n=269) Erhebungen notiert. Die rechtskonforme Fleischuntersuchung am bovinen bzw. porcinen Magen-Darm-Trakt wurde zu 7,5 % (n=18) resp. 6,7 % (n=17) beschrieben. Die Leberlymphknoten beim Schwein wurden laut 8,2 % (n=30) der Erhebungen vorschriftsgemäß untersucht. In 64,8 % (n=406) der Erhebungen wurden – zumeist mehrere – Tierschutzprobleme angegeben. Als Reaktion auf die Tierschutzprobleme wurden in 86,0 % (n=296) der Erhebungen Typ 2 und Typ 3 amtliche Maßnahmen dokumentiert. Schlussfolgerungen Die Konzentrierung der Praktikanten auf ausgewählte Schlachtbetriebe kann auf den bundesweiten Rückgang an geeigneten Praktikumsstätten infolge von Betriebsschließungen und Tierarten-spezialisierungen zurückgeführt werden. Für eine erleichterte Organisation des Praktikums ist daher (i) eine rechtlich fixierte Zutrittsberechtigung für veterinärmedizinische Praktikanten im Schlacht-betrieb und (ii) eine Reduktion der Praktikumsanforderungen von zwei auf eine Pflichttierart wichtig. Trotz dieser organisatorischen Schwierigkeiten hat sich das Praktikum aufgrund der vielfältigen Inhalte als wichtiges Ausbildungsformat bestätigt. Gleichwohl wurde die Vermittlung der obligatorischen Inhalte nicht von allen Teilnehmern angegeben, was eine Nichterfüllung der Studienvorgaben darstellt. Wie die Erhebung zeigte, kann dies durch eine mangelnde oder fehlerhafte Demonstration im Schlachtbetrieb begründet werden. Aus fachlicher und didaktischer Sicht ist der Anteil an Studierenden ohne Angabe der erweiterten Fleischuntersuchung im Verdachtsfall (23-30 %) besonders kritisch zu werten. Zum einen muss der amtliche Tierarzt nach europäischem Recht die erweiterte Fleischuntersuchung selbstständig durchführen, weswegen das praktische Erlernen essentiell wichtig ist. Zum anderen erfolgt diese Untersuchung am Ausschleusband, wodurch der ökonomische Druck auf die Tierärzte entfällt und ausreichend Übungszeit ohne Störung des Routinebetriebs gegeben ist. Die häufig dokumentierten Tierschutzprobleme können den Studierenden die Wichtigkeit der amtlichen Überwachung und der eigenen Tätigkeit während des Praktikums verdeutlichen. Abschließend zeigen die Untersuchungsergebnisse die Notwendigkeit einer verstärkten Kommunikation zwischen den Ausbildenden der Hochschulen und der zuständigen Behörden für eine optimale Nutzung des Lehrformates „Schlachthofpraktikum“. / Introduction Within the European law, the official veterinarian plays a key role in protecting public health and animal welfare. Before starting to work as a veterinarian in the area of meat hygiene, a 200-hour mandatory training has to be completed. Nevertheless, the importance of a practical training in ante- and post-mortem inspection during veterinary studies was highlighted both by law and by different organisations. The German Federal Licensure Act for Veterinarians requires a so-called "abattoir internship" of 100 hours which represents a quarter of the complete food hygienic time quota. Mandatory contents are training the ante- and post-mortem inspection of cattle and pigs, as well as informing about the treatment of slaughter animals. In the literature, there are exemplary, however, no comprehensive studies on the "abattoir internship" in Germany. Aim of the study This thesis investigates the extramural practical training of ante- and post-mortem meat inspection. Particular emphasis is put on the evaluation of students’ learning experiences as well as the opinions of students and official veterinarians. Furthermore, particular circumstances of the abattoir are examined. Materials and Methods In a cross-sectional study, two written, standardized methods (an evaluation according to the German Veterinary Medical Society and an in-house survey) were conducted amongst veterinary students of the University of Leipzig who graduated between 2008 and 2014. The evaluation included a checklist and each an opinion poll for students and official veterinarians. Due to improvements, three versions of the survey were used. Results The evaluation stated that 82.1 % (n=579) of the 705 participating students visited one and 17.9 % (n=126) several abattoirs for their practical training. Some abattoirs were named more frequently. About 95.7 % (n=675) of the students confirmed the mandatory internship contents (ante-mortem inspection: 95.7 %; n=674 / post-mortem inspection: 96.7 %; n=682 / animal welfare aspects: 95.7 %; n 675). About three quarters of the participants highlighted the extended meat inspection in suspected cases (cattle: 69.4 %; n=489 / pig: 76.7 %; n=541). Many students also mentioned additional topics, such as hygiene and slaughter technology. 79.4 % (n=559) of the trainees recorded a final interview. The opinions of both students and official veterinarians regarding the extramural practical training were largely positive. 54.7 % (n=242) of the official veterinarians claimed to have motivated students for postgraduate meat hygiene activities; only 31.1 % (n=138) of the students indicated this too. Particular situations at the abattoir were documented in the surveys. 97.6 % (n=249), respectively 96.1 % (n=269) of the surveys mentioned that the ante-mortem inspection of cattle or pigs was carried out. The legally compliant meat inspection of the bovine or porcine gastrointestinal tract was described in 7.5 % (n=18) respectively 6.7 % (n=17) of the cases. The liver lymph nodes in pigs were duly examined in 8.2 % (n=30) of the surveys. In 64.8 % (n=406) cases – usually several – animal welfare problems were indicated. In 86.0 % (n=296) of the type-2- and type-3-surveys, it was reported that official measures were taken against these problems. Conclusions The concentration of trainees on selected abattoirs can be explained by the nationwide decline in suitable placement sites due to abattoir closures and animal species specializations. To facilitate the organisation of the extramural practical training, it is important (i) to legally regulate an access authorization for veterinary trainees at the abattoirs and (ii) to reduce the placement requirements from two to one duty species. Despite these organisational difficulties, the many varied contents have confirmed that this internship plays an important role as a training format in the training of veterinary students. However, not all participants specified the treatment of each mandatory content, which means that in these cases, the study requirements were not fulfilled. As the survey showed, this can be justified by a lack of or incorrect demonstration at the abattoir. From a professional and didactic point of view, the proportion of students who did not specify the extended post-mortem inspection in suspected cases (23-30%) must be evaluated critically. On the one hand, the official veterinarian must autonomously perform the extended meat inspection in accordance with the European law. Therefore, the practical training is of essential importance. On the other hand, this inspection is carried out on a second slaughter line, which reduces the economic pressure on the veterinarians and offers sufficient practice time without disturbing the routine operation. The frequently documented animal welfare problems can show students the importance of official supervision and their own value as trainees. Finally, the results highlight the need for an enhanced communication between the trainers of the universities and of the competent authorities in order to achieve the optimal use of the teaching format "abattoir internship".

Over the last few years, policies have been introduced in the UK which aim to improve organ transplantation rates by changing the way that potential organ donors are treated before death. Patients incapacitated due to catastrophic brain injury may now undergo ante-mortem donor optimisation procedures to facilitate deceased organ donation. As I identify in this thesis, the most significant ethical and legal problem with these policies is that they are not based on what the patient would have chosen for themselves in the specific circumstances. The policies identify and treat patients meeting certain clinical criteria as a group rather than the individuals, with their own viewpoints, that the law on best interests requires. They equate registration on the Organ Donation Register with ante-mortem donor optimisation procedures being in their best interests, despite registrants having neither been informed about nor given consent to ante-mortem interventions. The overarching claim I make in this thesis is that a system of specific advance consent is needed to provide a clear and unequivocal legal justification for ante-mortem donor optimisation procedures. The ethical foundation for this claim is autonomy, and this is the central theme running through all six chapters. I argue that autonomy should be incorporated into donor optimisation policy to promote the dignity and integrity of potential organ donors and to safeguard trust in the organ donation programme. I argue that a system of specific advance consent is needed as part of the duty of care owed to registrants on the Organ Donor Register and to facilitate the determination of the best interests of the potential organ donor. I argue that the state has not established the necessity of the current policy of non-consensual donor optimisation procedures and that they are under an ethical and legal obligation to introduce an autonomy-based framework for ante-mortem interventions to facilitate organ donation.

Einleitung Der amtliche Tierarzt nimmt im europäischen Recht eine Schlüsselposition für den gesundheitlichen Verbraucherschutz und den Tierschutz von Schlachttieren ein. Zu Beginn der amtlichen fleisch-hygienischen Tätigkeit ist eine 200-stündige Pflichtassistenz vorgeschrieben. Gleichwohl wurde vor dem Hintergrund dieser verantwortungsvollen Tätigkeit die Wichtigkeit einer praktischen Ausbildung in der Schlachttier- und Fleischuntersuchung während des Veterinärmedizinstudiums sowohl rechtlich als auch durch verschiedene Organisationen hervorgehoben. In der Studienordnung nimmt das sogenannte „Schlachthofpraktikum“ mit 100 Stunden etwa ein Viertel der lebensmittelhygienischen Ausbildungszeit ein. Obligatorische Ziele dieses Lehrformats sind das Üben der amtlichen Ante- und Post-Mortem-Untersuchung bei den Tierarten Rind und Schwein, sowie das Informieren über die tierschutzgerechte Behandlung der Schlachttiere. In der Fachliteratur finden sich erste modellhafte, gleichwohl keine umfassenden Untersuchungen zum „Schlachthofpraktikum“ in Deutschland. Ziel der Untersuchung Daher widmet sich diese Dissertation einer tiefergehenden Untersuchung der praktischen Ausbildung in der Schlachttier- und Fleischuntersuchung. Hierbei sollten die studentischen Lernerfahrungen sowie die Meinungsbilder von Studierenden und amtlichen Tierärzten evaluiert und ausgewählte Situationen am Praktikumsschlachtbetrieb erhoben werden. Material und Methoden Im Rahmen einer Querschnittsstudie wurden zwei schriftliche, standardisierte Methoden (Evaluierung gemäß der Deutschen Veterinärmedizinischen Gesellschaft und eigene Erhebung) bei Leipziger Veterinärmedizinstudierenden der Abschlussjahrgänge 2008-2014 angewandt. Die Evaluierung umfasste eine Checkliste sowie je einen Bewertungsbogen für den Studierenden und den amtlichen Tierarzt. Die Erhebung kam aufgrund von Weiterentwicklungen in drei Versionen zur Anwendung. Ergebnisse Bei der Evaluierung gaben die 705 Studierenden an, zu 82,1 % (n=579) einen und zu 17,9 % (n=126) mehrere Praktikumsbetriebe besucht zu haben. Dabei wurden einige Betriebe mit zunehmender Häufigkeit benannt. Über 95,7 % (n=675) der Studierenden bestätigten die obligatorischen Praktikums-inhalte (Schlachttieruntersuchung: 95,7 %; n=674 / Fleischuntersuchung: 96,7 %; n=682 / Tierschutz-aspekte: 95,7 %; n=675). Die Fleischuntersuchung im Verdachtsfall markierten etwa drei Viertel der Teilnehmer (Rind: 69,4 %; n=489 / Schwein: 76,7 %; n=541). Viele Studierende gaben darüber hinaus weitere Themen an, wie bspw. Hygiene und Schlachttechnologie. Ein Abschlussgespräch notierten 79,4 % (n=559) der Praktikanten. Das Meinungsbild der Studierenden und amtlichen Tierärzte bzgl. des Praktikums fiel größtenteils positiv aus. 54,7 % (n=242) der amtlichen Tierärzte nahmen zudem an, die Studierenden für eine spätere fleischhygienische Tätigkeit motiviert zu haben; dem gegenüber gaben dies nur 31,1 % (n=138) der Studierenden an. Ausgewählte Situationen am Schlachtbetrieb wurden mithilfe der Erhebungen dokumentiert. Die Durchführung der Schlachttieruntersuchung beim Rind bzw. Schwein wurde in 97,6 % (n=249) resp. 96,1 % (n=269) Erhebungen notiert. Die rechtskonforme Fleischuntersuchung am bovinen bzw. porcinen Magen-Darm-Trakt wurde zu 7,5 % (n=18) resp. 6,7 % (n=17) beschrieben. Die Leberlymphknoten beim Schwein wurden laut 8,2 % (n=30) der Erhebungen vorschriftsgemäß untersucht. In 64,8 % (n=406) der Erhebungen wurden – zumeist mehrere – Tierschutzprobleme angegeben. Als Reaktion auf die Tierschutzprobleme wurden in 86,0 % (n=296) der Erhebungen Typ 2 und Typ 3 amtliche Maßnahmen dokumentiert. Schlussfolgerungen Die Konzentrierung der Praktikanten auf ausgewählte Schlachtbetriebe kann auf den bundesweiten Rückgang an geeigneten Praktikumsstätten infolge von Betriebsschließungen und Tierarten-spezialisierungen zurückgeführt werden. Für eine erleichterte Organisation des Praktikums ist daher (i) eine rechtlich fixierte Zutrittsberechtigung für veterinärmedizinische Praktikanten im Schlacht-betrieb und (ii) eine Reduktion der Praktikumsanforderungen von zwei auf eine Pflichttierart wichtig. Trotz dieser organisatorischen Schwierigkeiten hat sich das Praktikum aufgrund der vielfältigen Inhalte als wichtiges Ausbildungsformat bestätigt. Gleichwohl wurde die Vermittlung der obligatorischen Inhalte nicht von allen Teilnehmern angegeben, was eine Nichterfüllung der Studienvorgaben darstellt. Wie die Erhebung zeigte, kann dies durch eine mangelnde oder fehlerhafte Demonstration im Schlachtbetrieb begründet werden. Aus fachlicher und didaktischer Sicht ist der Anteil an Studierenden ohne Angabe der erweiterten Fleischuntersuchung im Verdachtsfall (23-30 %) besonders kritisch zu werten. Zum einen muss der amtliche Tierarzt nach europäischem Recht die erweiterte Fleischuntersuchung selbstständig durchführen, weswegen das praktische Erlernen essentiell wichtig ist. Zum anderen erfolgt diese Untersuchung am Ausschleusband, wodurch der ökonomische Druck auf die Tierärzte entfällt und ausreichend Übungszeit ohne Störung des Routinebetriebs gegeben ist. Die häufig dokumentierten Tierschutzprobleme können den Studierenden die Wichtigkeit der amtlichen Überwachung und der eigenen Tätigkeit während des Praktikums verdeutlichen. Abschließend zeigen die Untersuchungsergebnisse die Notwendigkeit einer verstärkten Kommunikation zwischen den Ausbildenden der Hochschulen und der zuständigen Behörden für eine optimale Nutzung des Lehrformates „Schlachthofpraktikum“. / Introduction Within the European law, the official veterinarian plays a key role in protecting public health and animal welfare. Before starting to work as a veterinarian in the area of meat hygiene, a 200-hour mandatory training has to be completed. Nevertheless, the importance of a practical training in ante- and post-mortem inspection during veterinary studies was highlighted both by law and by different organisations. The German Federal Licensure Act for Veterinarians requires a so-called "abattoir internship" of 100 hours which represents a quarter of the complete food hygienic time quota. Mandatory contents are training the ante- and post-mortem inspection of cattle and pigs, as well as informing about the treatment of slaughter animals. In the literature, there are exemplary, however, no comprehensive studies on the "abattoir internship" in Germany. Aim of the study This thesis investigates the extramural practical training of ante- and post-mortem meat inspection. Particular emphasis is put on the evaluation of students’ learning experiences as well as the opinions of students and official veterinarians. Furthermore, particular circumstances of the abattoir are examined. Materials and Methods In a cross-sectional study, two written, standardized methods (an evaluation according to the German Veterinary Medical Society and an in-house survey) were conducted amongst veterinary students of the University of Leipzig who graduated between 2008 and 2014. The evaluation included a checklist and each an opinion poll for students and official veterinarians. Due to improvements, three versions of the survey were used. Results The evaluation stated that 82.1 % (n=579) of the 705 participating students visited one and 17.9 % (n=126) several abattoirs for their practical training. Some abattoirs were named more frequently. About 95.7 % (n=675) of the students confirmed the mandatory internship contents (ante-mortem inspection: 95.7 %; n=674 / post-mortem inspection: 96.7 %; n=682 / animal welfare aspects: 95.7 %; n 675). About three quarters of the participants highlighted the extended meat inspection in suspected cases (cattle: 69.4 %; n=489 / pig: 76.7 %; n=541). Many students also mentioned additional topics, such as hygiene and slaughter technology. 79.4 % (n=559) of the trainees recorded a final interview. The opinions of both students and official veterinarians regarding the extramural practical training were largely positive. 54.7 % (n=242) of the official veterinarians claimed to have motivated students for postgraduate meat hygiene activities; only 31.1 % (n=138) of the students indicated this too. Particular situations at the abattoir were documented in the surveys. 97.6 % (n=249), respectively 96.1 % (n=269) of the surveys mentioned that the ante-mortem inspection of cattle or pigs was carried out. The legally compliant meat inspection of the bovine or porcine gastrointestinal tract was described in 7.5 % (n=18) respectively 6.7 % (n=17) of the cases. The liver lymph nodes in pigs were duly examined in 8.2 % (n=30) of the surveys. In 64.8 % (n=406) cases – usually several – animal welfare problems were indicated. In 86.0 % (n=296) of the type-2- and type-3-surveys, it was reported that official measures were taken against these problems. Conclusions The concentration of trainees on selected abattoirs can be explained by the nationwide decline in suitable placement sites due to abattoir closures and animal species specializations. To facilitate the organisation of the extramural practical training, it is important (i) to legally regulate an access authorization for veterinary trainees at the abattoirs and (ii) to reduce the placement requirements from two to one duty species. Despite these organisational difficulties, the many varied contents have confirmed that this internship plays an important role as a training format in the training of veterinary students. However, not all participants specified the treatment of each mandatory content, which means that in these cases, the study requirements were not fulfilled. As the survey showed, this can be justified by a lack of or incorrect demonstration at the abattoir. From a professional and didactic point of view, the proportion of students who did not specify the extended post-mortem inspection in suspected cases (23-30%) must be evaluated critically. On the one hand, the official veterinarian must autonomously perform the extended meat inspection in accordance with the European law. Therefore, the practical training is of essential importance. On the other hand, this inspection is carried out on a second slaughter line, which reduces the economic pressure on the veterinarians and offers sufficient practice time without disturbing the routine operation. The frequently documented animal welfare problems can show students the importance of official supervision and their own value as trainees. Finally, the results highlight the need for an enhanced communication between the trainers of the universities and of the competent authorities in order to achieve the optimal use of the teaching format "abattoir internship".