• Journal of Animal Science and Technology
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• v.46 no.1
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• pp.97-106
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• 2004

The study was conducted to investigate the effects of practical variations in feed restriction, pre-slaughter handing and chilling regime on pork quality during ageing. A total of twenty male landraces were allocated into three treatments(i.e., pre-slaughter feeding, stress and chilling regime) in a factorial arrangement. pH, temperature, free calcium ions, WB-shear force, sarcomere length, cooking loss, drip loss and objective color were determined during rigor development and/or 1, 3, 7 d postmortem. Pre-slaughter chasing stress for approximately 15 min had no effects on pH/temperature profile and objective meat quality. There was an interaction(P < 0.05) between the fasting treatment and chi1ling regime for muscle temperature at pH 6.2. Sarcomere length indicated that the current experiment conditions did not induce muscle shortening, with 1.7 to 1.8 ${\mu}m$, in spite of a significant effect of the fasting treatment (P<0.01). Pigs fed until the morning of slaughter showed a low WB-shear force(P < 0.05) until 3 d at I "C. The treatment also resulted in a higher Hunter L* and a*(P < 0.05) at 24 h and 7 d. Fasted pigs showed a significantly(P < 0.05) reduced cooking loss. The current results indicated that feeding upon the morning of slaughter became detrimental on meat color and the negative effect on cooking loss were linearly elevated with increased ageing time. On the other hand, WB-shear force did not distinguishable after 3 d. Collectively, it appeared that feed restriction from a day before slaughter could produce more a desirable meat quality at the time of consuming. However, the limited effect of animal handling and chilling rate on meat quality is not necessarily to extend to that these do not affect pork quality, as that largely depends on experimental design.

• Journal of The Korean Association For Science Education
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• v.42 no.1
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• pp.77-96
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• 2022

This study investigated how collaborative reflection between novice secondary science teachers promoted the development of teaching professionalism. We intentionally selected research participants who shared sufficient rapport. Data were collected by videotaping the classes taught by participants, pre-talk, post-interviews and nine collaborative reflection processes. All data were transcribed and analyzed. Results indicated that all three teachers showed changes in teaching practice. Minyoung's practice involved a teacher-led lecture, but through collaborative reflection, she could create a learning environment to enhance students' power and ownership in her class. Emphasizing academic rigor, Soyoung used to teach content outside the scope of the curriculum, but through collaborative reflection, she became more considerate of students' understanding. Finally, in Jiyeon's classes inquiry activities and theoretical explanations were separated from each other. However, she repeated her efforts to improve her class after collaborative reflection, allowing students to construct explanations through activities. In this study, three factors that promoted the development of teachers' pedagogical content knowledge through collaborative reflection were identified. First, the different teaching orientations of the three teachers who participated in this study, promoted sharing of opinions through collaborative reflection. Second, reflection based on teaching practice enabled practical feedback on the class, which enhanced the development of teachers' pedagogical content knowledge. Third, the equal status and formation of rapport between the three teachers created an environment for productive reflection. These results suggest that future teacher education programs should target communities that can promote collaborative reflection based on teachers' teaching practice.