This study aimed to evaluate the effects of different stunning frequencies and electrical current waveforms on chicken welfare and meat quality. Two-hundred-thirty-two Cobb broilers, 48 d of age and 2.76 ± 0.47 live-weight, were randomly assigned into 4 stunning treatments - 2 frequencies (300 Hz and 650 Hz) and 2 current waveforms (direct current [DC] and alternating current [AC]). Broilers were electrically stunned in a water bath in a commercial slaughterhouse (70 V, 100 mA). The electronarcosis and stunning efficiency were confirmed by assessment of visual parameters (absence of rhythmic breathing, ocular reflex, and coordinated wing flapping) and blood parameters (lactate, glucose, creatine kinase, sodium, and potassium), which were measured after bleeding. The incidence of traumas and injuries was assessed after plucking. Meat quality analysis was performed in Pectoralis major (PM), with determinations of pH, breast yield (PMY), water holding capacity (WHC), water absorption capacity (WAC), thawing loss (DL), cooking loss (CL), shear force (SF), and instrumental color (a*, b*, L*, C*, and h). The interaction between waveform and frequency was significant (P < 0.05) only for lactate, sodium, and lightness (L*). Lactate and sodium levels decreased at 300 Hz-DC. Meat lightness increased at 300 Hz-DC. The individual effect of frequency was significant for glucose, creatine kinase, potassium, WHC, PMY, b*, C*, and h. Regarding waveform, AC decreased plasma glucose and DC decreased creatine kinase and WAC. In general, stunning frequency exerts greater influence than waveform on the welfare and meat quality parameters of broilers. The use of frequency at 650 Hz proved to render animals efficiently unconscious and to promote greater meat quality.
The shelf life extending effect of different modified atmospheres packages (MAP): vacuum (MAP-1), 69.6% N 2 + 30% CD 2 + 0.4% CD (MAP-2) and 70% D 2 + 30% CD 2 (MAP-3) on lamb meat at two slaughter ages (4 and 8-month-old) was assessed. pH decreased as slaughter age (SA) increased, and increased during longer storage time (ST), with no MAP effects. Lamb meat stored in MAP-1 and MAP-3 showed greater drip loss than that stored in MAP-2. Shear force was not influenced by SA and MAP treatments, but decreased during ST. Meat from 8-month-old lambs packaged in MAP-3 at longer ST resulted in lipid oxidation increase. MAP-2 enhanced color saturation and lamb meat redness, whereas MAP-3 showed lowest redness and chroma values, and highest aerobic psychrotropic count. Meat from 4-month-old lamb stored in MAP-3 presented shortest shelf life based on psychrotropic bacteria growth. The association of higher SA with high D 2 MAP proved to compromise oxidative stability of lamb meat, adversely affecting its shelf life. Vacuum and CD packaging showed similar effects on lamb meat preservation; however, CD had advantage in maintaining fresh red color of meat.
RESUMOCurrículos de medicina veterinária devem disponibilizar ferramentas para que os futuros profissionais atendam a demanda da sociedade, que inclui preocupações diretas com os animais. O objetivo deste trabalho foi traçar um perfil do panorama geral do ensino da medicina veterinária em relação a questões de bem-estar e dor animal. O método utilizado foi análise de documentos disponíveis online e coleta de dados via aplicação de questionários para coordenadores de curso de medicina veterinária. A descrição do curso, sua grade curricular e ementário foram estudados. Observou-se que 46% das 94 instituições estudadas apresentavam a disciplina de bem-estar animal e 26% ofereciam a disciplina de etologia. Houve evidência de que há uma pronta relação com a esfera física do bem-estar animal, sendo que as outras duas esferas, comportamental e psicológica, não recebem atenção similar ao longo dos cursos. Na avaliação do ementário, o termo "bem-estar animal" é empregado com caráter difuso e o termo "dor" encontra-se presente em 54% dos cursos estudados, relacionado principalmente a disciplinas de patologia, fisiologia, farmacologia e anestesiologia. Conclui-se que o ensino brasileiro de medicina veterinária enfatiza a esfera física do bem-estar animal, sendo importante o enriquecimento em relação às esferas comportamental e psicológica e ao ensino da dor.Palavras-chave: bem-estar animal, currículo, dor animal, ensino, medicina veterinária ABSTRACT
The aim here is to present data on the efficacy of anthelmintics in sheep flocks in Rio de Janeiro, Brazil, and to discuss the interpretation of the fecal egg count reduction test (FECRT) for each nematode genus. Fecal eggs counts and pre- and post-treatment coprocultures were performed, the former to evaluate the efficacy of and the latter to determine the overall parasite prevalence. An additional efficacy test was performed at Farm # 1 a year after the initial test. Severe anthelmintic resistance was found for the flocks, with no FECRT sensitivity at any of the 22 farms evaluated. However, an analysis of the infective larvae showed that some drugs were effective against certain parasitic genera; i.e., levamisole was more effective against Haemonchus spp. and moxidectin against Trichostrongylus spp. In the additional FECRT performed at Farm # 1, moxidectin and nitroxynil were ineffective separately, but when applied in combination they were highly effective due to their efficacy against Haemonchus (nitroxynil) and Trichostrongylus (moxidectin), respectively. The use of the FECRT targeting the parasitic nematode species prevalent on farms may make it possible to choose more effective anthelmintics.
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