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.

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.

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.

As infecções causadas por Campylobacter spp. são relatadas como causa freqüente de gastrenterites de origem alimentar em vários países do mundo. As espécies bacterianas termofílicas pertencentes ao gênero Campylobacter, principalmente Campylobacter jejuni e Campylobacter coli, têm sido isoladas de fezes de animais e estão associadas à contaminação da carne durante o processo de abate. Estas duas espécies são as mais freqüentemente envolvidas nos casos de campilobacteriose humana veiculada por alimentos. O presente estudo pretendeu avaliar a presença e a população de Campylobacter spp. no abate de bovinos e cortes refrigerados de aves e bovinos comercializados na cidade de São Paulo/SP. Um total de 198 animais foi amostrado no couro logo após a sangria, na carcaça imediatamente após a esfola e após a evisceração. As amostras foram obtidas através da técnica de swab na região do peito abrangendo uma área de 400 cm2. Foram analisados também 120 cortes refrigerados de frango e 100 cortes de carne bovina, assim distribuídos: 40 amostras de asa, 20 de coxa com sobrecoxa, 20 de coxa, 20 de coxinha da asa, 20 amostras de peito; 20 de patinho bovino (M. biceps femoris), 20 de contrafilé (M. longissimus dorsi), 20 de coxão mole (M. semi membranosus), 20 de lagarto (M. semitendinosus) e 20 de alcatra (M. glutaes medius). As amostras foram analisadas segundo os métodos ISO 10272-1 e 2 e os isolados obtidos foram confirmados como Campylobacter pela técnica de PCR. Campylobacter foi isolado em 22,7% (45/198) das amostras de couro bovino, ou seja, apenas no ponto antes da esfola, e C. jejuni foi a única espécie encontrada. Nas amostras de cortes de frango Campylobacter foi isolado em 14,2% (17/120) das amostras. A espécie prevalente em frangos foi C. coli (88%), seguido de C. jejuni (12%). Campylobacter spp. não foi isolado dos cortes bovinos. A população de Campylobacter spp. foi < 13 UFC/cm2 em carcaças bovinas, < 2 UFC/g em amostras de frango e < 10 UFC/cm2 em cortes bovinos. A susceptibilidade de 120 isolados de frango e couro bovino foi determinada frente a 8 agentes antimicrobianos usando o método de disco-difusão. A resistência às quinolonas (ác. nalidíxico e ciprofloxacina) foi frequentemente observada nas cepas de C. jejuni (72,2%) e C. coli (50,8%) isoladas dos frangos. Entre os isolados de C. jejuni obtidos do couro bovino maior taxa de resistência foi observada para estreptomicina (32%), seguida da eritromicina (16%) e do ácido nalidíxico (14%). / Campylobacter spp. infections are reported as a frequent cause of foodborne gastroenteritis in many countries. The thermophilic bacterial species belonging to the genus Campylobacter, particularly Campylobacter jejuni and Campylobacter coli have been isolated from feces of animals and are associated with the contamination of meat during the slaughtering process. These two species are the most frequently involved in cases of human campylobacteriosis conveyed by food. The aim of the present study was to evaluate the presence and population of Campylobacter spp. during cattle slaughter and in refrigerated chicken and beef cuts commercialized in the city of Sao Paulo/SP. A total of 198 animals were sampled in the hide after bleeding, the carcass immediately after skinning and after evisceration. Samples were obtained by swab technique in the chest area encompassing an area of 400 cm2. We also analyzed 120 refrigerated chicken cuts and 100 beef cuts. The samples were analyzed according to ISO 10272-1 and 2 methods and the isolates were confirmed as Campylobacter by PCR technique. Campylobacter was isolated only in the hide samples (45/198), and C. jejuni was the only species found. Campylobacter was isolated in 14.2% (17/120) of chicken samples. The most prevalent species in chickens was C. coli (88%), followed by C. jejuni (12%). Campylobacter spp. was not isolated from beef cuts. The counts of Campylobacter spp. was < 13 CFU/cm2 in bovine carcasses, < 2 CFU/g in chicken samples and < 10 CFU/cm2 in beef cuts. The susceptibility to 8 antimicrobial agents of 120 isolates of chicken and bovine hide was determined using the disk-diffusion method. The resistance to quinolones (ciprofloxacin and nalidixic acid) was frequently observed in strains of C. jejuni (72.2%) and C. coli (50.8%) isolated from chickens. Among strains of C. jejuni obtained from bovine hide highest resistance rate was observed to streptomycin (32%), followed by erythromycin (16%) and nalidixic acid (14%).

As infecções causadas por Campylobacter spp. são relatadas como causa freqüente de gastrenterites de origem alimentar em vários países do mundo. As espécies bacterianas termofílicas pertencentes ao gênero Campylobacter, principalmente Campylobacter jejuni e Campylobacter coli, têm sido isoladas de fezes de animais e estão associadas à contaminação da carne durante o processo de abate. Estas duas espécies são as mais freqüentemente envolvidas nos casos de campilobacteriose humana veiculada por alimentos. O presente estudo pretendeu avaliar a presença e a população de Campylobacter spp. no abate de bovinos e cortes refrigerados de aves e bovinos comercializados na cidade de São Paulo/SP. Um total de 198 animais foi amostrado no couro logo após a sangria, na carcaça imediatamente após a esfola e após a evisceração. As amostras foram obtidas através da técnica de swab na região do peito abrangendo uma área de 400 cm2. Foram analisados também 120 cortes refrigerados de frango e 100 cortes de carne bovina, assim distribuídos: 40 amostras de asa, 20 de coxa com sobrecoxa, 20 de coxa, 20 de coxinha da asa, 20 amostras de peito; 20 de patinho bovino (M. biceps femoris), 20 de contrafilé (M. longissimus dorsi), 20 de coxão mole (M. semi membranosus), 20 de lagarto (M. semitendinosus) e 20 de alcatra (M. glutaes medius). As amostras foram analisadas segundo os métodos ISO 10272-1 e 2 e os isolados obtidos foram confirmados como Campylobacter pela técnica de PCR. Campylobacter foi isolado em 22,7% (45/198) das amostras de couro bovino, ou seja, apenas no ponto antes da esfola, e C. jejuni foi a única espécie encontrada. Nas amostras de cortes de frango Campylobacter foi isolado em 14,2% (17/120) das amostras. A espécie prevalente em frangos foi C. coli (88%), seguido de C. jejuni (12%). Campylobacter spp. não foi isolado dos cortes bovinos. A população de Campylobacter spp. foi < 13 UFC/cm2 em carcaças bovinas, < 2 UFC/g em amostras de frango e < 10 UFC/cm2 em cortes bovinos. A susceptibilidade de 120 isolados de frango e couro bovino foi determinada frente a 8 agentes antimicrobianos usando o método de disco-difusão. A resistência às quinolonas (ác. nalidíxico e ciprofloxacina) foi frequentemente observada nas cepas de C. jejuni (72,2%) e C. coli (50,8%) isoladas dos frangos. Entre os isolados de C. jejuni obtidos do couro bovino maior taxa de resistência foi observada para estreptomicina (32%), seguida da eritromicina (16%) e do ácido nalidíxico (14%). / Campylobacter spp. infections are reported as a frequent cause of foodborne gastroenteritis in many countries. The thermophilic bacterial species belonging to the genus Campylobacter, particularly Campylobacter jejuni and Campylobacter coli have been isolated from feces of animals and are associated with the contamination of meat during the slaughtering process. These two species are the most frequently involved in cases of human campylobacteriosis conveyed by food. The aim of the present study was to evaluate the presence and population of Campylobacter spp. during cattle slaughter and in refrigerated chicken and beef cuts commercialized in the city of Sao Paulo/SP. A total of 198 animals were sampled in the hide after bleeding, the carcass immediately after skinning and after evisceration. Samples were obtained by swab technique in the chest area encompassing an area of 400 cm2. We also analyzed 120 refrigerated chicken cuts and 100 beef cuts. The samples were analyzed according to ISO 10272-1 and 2 methods and the isolates were confirmed as Campylobacter by PCR technique. Campylobacter was isolated only in the hide samples (45/198), and C. jejuni was the only species found. Campylobacter was isolated in 14.2% (17/120) of chicken samples. The most prevalent species in chickens was C. coli (88%), followed by C. jejuni (12%). Campylobacter spp. was not isolated from beef cuts. The counts of Campylobacter spp. was < 13 CFU/cm2 in bovine carcasses, < 2 CFU/g in chicken samples and < 10 CFU/cm2 in beef cuts. The susceptibility to 8 antimicrobial agents of 120 isolates of chicken and bovine hide was determined using the disk-diffusion method. The resistance to quinolones (ciprofloxacin and nalidixic acid) was frequently observed in strains of C. jejuni (72.2%) and C. coli (50.8%) isolated from chickens. Among strains of C. jejuni obtained from bovine hide highest resistance rate was observed to streptomycin (32%), followed by erythromycin (16%) and nalidixic acid (14%).