- 著者
- Kawasaki Takeshi Iwasaki Tomohito Yamada Michi Yoshida Takashi Watanabe Takafumi
- 出版者
- PLOS
- 雑誌
- PLoS ONE
- 巻号頁・発行日
- vol.13, no.2, pp.e0193307-1-e0193307-14, 2018-02
- 被引用文献数
- 30
The high incidence of meat of impaired quality poses a serious problem in the poultry industry. In recent years, the incidence of the pectoralis major muscle that appeared pale colored, remarkably hardened, and exudative, called “wooden breast” or “woody breast” has increased in slaughter houses. In the present study, 19-day-old Ross 308 broiler chickens affected (n = 10) and unaffected (n = 10) with remarkably hardened breast were selected from a commercial broiler farm, and reared to 55 days of age under a controlled environment. Among the affected birds, 5 of 10 birds appeared exhausted with markedly suppressed weight gain and 4 of 10 birds died during the rearing period. In contrast, all unaffected birds survived and most gained weight. Four of 10 unaffected birds lost the ability of back-to-back wing contact by the late stage of rearing. The biochemical analysis of blood plasma samples of 20-day-old birds revealed that creatine kinase and L-aspartate aminotransferase values in most affected birds were higher than those in unaffected birds; however, these values in unaffected birds increased rapidly with lost wing contactability and increasing age. Postmortem examinations revealed that the mean diameter of myofibers in affected birds was smaller than that in unaffected birds. Moreover, symptoms of degenerative and regenerative muscles were observed in most birds in both groups. Among them, a decrease in, or defect of, the characteristic polygonal shape of myofibers was the most common change within the pectoralis major muscles in both groups. The present study demonstrated that broilers affected with remarkably hardened breast during the middle stage of rearing would have suppressed physical status and weight gain, or would die. It was suggested that rapid growth in broilers might be a cause of remarkably hardened breast.
- 著者
- 吉田 卓司 松浦 均 YOSHIDA Takashi MATSUURA Hitoshi
- 出版者
- 三重大学教育学部
- 雑誌
- 三重大学教育学部研究紀要. 自然科学・人文科学・社会科学・教育科学・教育実践 = BULLETIN OF THE FACULTY OF EDUCATION MIE UNIVERSITY. Natural Science,Humanities,Social Science,Education,Educational Practice (ISSN:18802419)
- 巻号頁・発行日
- vol.69, pp.279-289, 2018-01-04
本研究では、高校生の学習上の援助行動である学業的援助授与およびその抑制態度の特徴を検討した。そのために授業内での援助行動を想定し、援助要請者を親しいクラスメイトおよびそれほど親しくないクラスメイトに区別して質問紙調査を行った。その結果、高校生の学業的援助授与には、放任的援助授与、熟考的援助授与、助言的援助授与が、その抑制態度には、回答への不安、理解不足による回答困難、要請者への抵抗感、人間関係への不安、説明への不安、能力感への脅威の存在が明らかになった。さらに「動機づけ-抑制態度-援助授与」の因果モデルを構築し、検討を行った結果、熟達目標は助言的援助授与に直接、または回答困難を媒介して熟考的援助授与に、遂行接近目標は人間関係への不安を媒介して、助言的援助授与に正の影響を与えることが明らかになった。また、遂行回避目標は、人間関係への不安を除く5つの抑制態度に正の影響を与え、一方、社会的コンピテンスは、要請者への抵抗感を除く5つの抑制態度に負の影響を与えることが明らかになった。援助要請者別の因果モデルにおいては、放任的援助授与に与える影響の違いなどが確認された。