Pathological analysis and etiological assessment of pulmonary lesions and its association with pleurisy in slaughtered pigs.

The intensification of pig farming has posed significant challenges in managing and preventing sanitary problems, particularly diseases of the respiratory complex. Monitoring at slaughter is an important control tool and cannot be overstated. Hence, this study aimed at characterizing both macroscopical and microscopical lesions and identifying the Actinobacillus pleuropneumoniae (APP), Mycoplasma hyopneumoniae (Mhyo), and Pasteurella multocida (PM) associated with pleurisy in swine. For this, a selected slaughterhouse in São Paulo State underwent a thorough examination of carcasses on the slaughter line, followed by lung sampling. The carcasses and lungs underwent macroscopical examination and were classified according to the score of pleurisy and lung samples were allocated into five groups, being: G0: score 0 - no lesions; G1: score 1; G2: score 2; G3: score 3; and G4: score 4. In total, 217 lung fragments were collected, for the histopathological evaluation and detection of the following respiratory pathogens: APP, Mhyo, and PM by qPCR. The results demonstrated that Mhyo and APP were the most prevalent etiological agents (single and co-identification) in lung samples, in different scores of pleurisies, while bronchopneumonia and bronchus-associated lymphoid tissue (BALT) hyperplasia lesions were the most frequent histopathological findings. Positive correlations were found between the quantification of APP DNA with 1) the score of pleurisy (R=0.254); 2) with the score of lung consolidation in all lung lobes (R=0.181 to R=0.329); and 3) with the score of lung consolidation in the entire lung (R=0.389). The study brings relevant information regarding the main bacterial pathogens associated with pleurisy in pigs and helps with understanding the relationship between the abovementioned pathogens and their impact on the respiratory health of pigs.

Associations between Pleurisy and the Main Bacterial Pathogens of the Porcine Respiratory Diseases Complex (PRDC).

Porcine Respiratory Diseases Complex (PRDC) is a multifactorial disease that involves several bacterial pathogens, including Mycoplasma hyopneumoniae (M. hyopneumoniae), Actinobacillus pleuropneumoniae (A. pleuropneumoniae), Pasteurella multocida (P. multocida), Glaesserella parasuis (G. parasuis), and Streptococcus suis (S. suis). In pigs, the infection may cause lesions such pleurisy, which can lead to carcass condemnation. Hence, 1015 carcasses were selected from three different commercial pig farms, where the respiratory conditions were evaluated using slaughterhouse pleurisy evaluation system (SPES) and classified into five groups. In total, 106 pleural and lung fragments were collected for qPCR testing to identify the five abovementioned pathogens. A moderate correlation between the severity of the lesions and the presence of P. multocida (R = 0.38) and A. pleuropneumoniae (R = 0.28) was observed. Concerning the lung samples, the severity of the lesions was moderately correlated with the presence of P. multocida (R = 0.43) and M. hyopneumoniae (R = 0.35). Moreover, there was a strong correlation between the presence of P. multocida and M.hyopneumoniae in the pleura (R = 0.82). Finally, this approach may be a useful tool to identify and quantify causative agents of PRDC using qPCR, providing a comprehensive evaluation of its relevance, strength, and potential application in the field as a surveillance tool for veterinarians.

Influência da insensibilização inadequada durante o abate de suínos nas propriedades físico-químicas da carne / Influence of inadequate sttuning during swine slaughter on the meat physical-chemical properties

Objetivou-se avaliar a influência da insensibilização inadequada durante o abate de suínos na cor, pH e perdas de água da carne. Após eletrocussão dos animais em um abatedouro-frigorífico sob SIF da região da Zona da Mata, Minas Gerais, parâmetros de insensibilização foram avaliados em 3.347 suínos abatidos. Os parâmetros avaliados foram ausência de reflexos palpebrais, reflexo de orelhas, gritos, pedalagem nos membros anteriores e respiração arrítmica. Após o completo abate e 16 horas de estocagem das carcaças em câmara fria a 2°C, fragmentos transversais do músculo Longissimus dorsi foram obtidos de animais selecionados de forma randomizada e insensibilizados de forma adequada (n=12) e inadequada (n=12). As amostras de carne foram avaliadas quanto ao pH, Capacidade de Retenção de Água (CRA). Do total de 3.347 suínos abatidos, 272 (8,13%) apresentaram pelo menos algum sinal de insensibilização inadequada. Observou-se que as 24 amostras de carne tiveram pH médio de 6,06, perda média de 24,74% de água e escore médio de 3,64 na escala de cor avaliada. O pH médio da carne obtida de animais inadequadamente insensibilizados (6,11) foi maior (p<0,05) que o pH médio de animais adequadamente insensibilizados (6,01). Quanto menor o pH da carne menor era o seu escore de cor e CRA (p<0,05). Portanto, a carne obtida de suínos mal insensibilizados possui maior pH, o que resulta em carne mais escura e com baixa CRA.(AU)

The objective of study was to evaluate the influence of inadequate sttuning during the swine slaughter in color, pH, and water loss of meat. After electric sttuning of animals in a slaugtherhouse under SIF of the Zona da Mata region, Minas Gerais, stunning parameters were evaluated in 3,347 slaughtered swines. The parameters evaluated were the absence of eyelid reflexes, ear reflexes, screams, pedaling in the forelimbs and arrhythmic breathing. After the full 16 hours of slaughter and storage of carcases in a cold chamber at 2°C, transverse fragments Longissimus dorsi muscle were obtained from randomly selected animals and properly (n=12) and improperly (n=12) sttuninged animals. The meat samples were evaluated for pH, Water Holding Capacity (WHC). Of the 3,347 slaughtered swines, 272 (8.13%) showed at least some sign of inadequate sttuning. It was observed that the 24 meat samples had mean pH of 6.06, mean loss water of 24.74% and mean score of 3.64 evaluated in color scale. The mean pH of meat obtained from animals improperly sttuninged (6.11) was greater (p<0.05) than the mean pH of animal properly sttuninged (6.01). The lower pH of meat causes lower color score and WHC (p<0.05). Therefore, the meat obtained from improperly sttuninged swine has a higher pH, which results in darker meat and low WHC.(AU)

Influência da insensibilização inadequada durante o abate de suínos nas propriedades físico-químicas da carne / Influence of inadequate sttuning during swine slaughter on the meat physical-chemical properties

Objetivou-se avaliar a influência da insensibilização inadequada durante o abate de suínos na cor, pH e perdas de água da carne. Após eletrocussão dos animais em um abatedouro-frigorífico sob SIF da região da Zona da Mata, Minas Gerais, parâmetros de insensibilização foram avaliados em 3.347 suínos abatidos. Os parâmetros avaliados foram ausência de reflexos palpebrais, reflexo de orelhas, gritos, pedalagem nos membros anteriores e respiração arrítmica. Após o completo abate e 16 horas de estocagem das carcaças em câmara fria a 2°C, fragmentos transversais do músculo Longissimus dorsi foram obtidos de animais selecionados de forma randomizada e insensibilizados de forma adequada (n=12) e inadequada (n=12). As amostras de carne foram avaliadas quanto ao pH, Capacidade de Retenção de Água (CRA). Do total de 3.347 suínos abatidos, 272 (8,13%) apresentaram pelo menos algum sinal de insensibilização inadequada. Observou-se que as 24 amostras de carne tiveram pH médio de 6,06, perda média de 24,74% de água e escore médio de 3,64 na escala de cor avaliada. O pH médio da carne obtida de animais inadequadamente insensibilizados (6,11) foi maior (p<0,05) que o pH médio de animais adequadamente insensibilizados (6,01). Quanto menor o pH da carne menor era o seu escore de cor e CRA (p<0,05). Portanto, a carne obtida de suínos mal insensibilizados possui maior pH, o que resulta em carne mais escura e com baixa CRA.

The objective of study was to evaluate the influence of inadequate sttuning during the swine slaughter in color, pH, and water loss of meat. After electric sttuning of animals in a slaugtherhouse under SIF of the Zona da Mata region, Minas Gerais, stunning parameters were evaluated in 3,347 slaughtered swines. The parameters evaluated were the absence of eyelid reflexes, ear reflexes, screams, pedaling in the forelimbs and arrhythmic breathing. After the full 16 hours of slaughter and storage of carcases in a cold chamber at 2°C, transverse fragments Longissimus dorsi muscle were obtained from randomly selected animals and properly (n=12) and improperly (n=12) sttuninged animals. The meat samples were evaluated for pH, Water Holding Capacity (WHC). Of the 3,347 slaughtered swines, 272 (8.13%) showed at least some sign of inadequate sttuning. It was observed that the 24 meat samples had mean pH of 6.06, mean loss water of 24.74% and mean score of 3.64 evaluated in color scale. The mean pH of meat obtained from animals improperly sttuninged (6.11) was greater (p<0.05) than the mean pH of animal properly sttuninged (6.01). The lower pH of meat causes lower color score and WHC (p<0.05). Therefore, the meat obtained from improperly sttuninged swine has a higher pH, which results in darker meat and low WHC.