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2. Pasteurisation of egg albumen caused a decrease in viable cells of less than 10‐fold, while pasteurisation of whole egg caused decreases of more than 100‐fold in only two of the eight strains studied. After growth in whole egg, some strains were more resistant to pasteurisation in whole egg.
3. Strep, faecalis multiplied in raw and pasteurised whole egg but not in egg albumen.
4. Strep, faecium multiplied in raw and pasteurised whole egg only after an initial decline in viability which was not shown by cells adapted to whole egg. Together with storage temperature this affected the number of viable cells after a storage period of 5 d.
5. In raw and pasteurised egg albumen Strep, faecium strains lost viability; this was maximal at 37 °C and more cells survived as the storage temperature decreased. 相似文献
2. Increased mortality, perosis and other pathological changes involving a number of tissues were observed in birds fed on a low‐choline diet.
3. Methionine replaced part of the dietary requirement for choline at low dietary choline concentrations.
4. High dietary concentrations of choline (> 1 750 mg/kg) increased the requirement for dietary TSAA.
5. Increasing the dietary choline while maintaining the TSAA at an inadequate level may decrease performance. 相似文献
4. Bruising was classified as light or bad bruising and it is suggested that this division represents two distinct types of bruises with different causes.
3. The incidence of bruising was greater in female flocks than in male although the bruising in the former tended to be less severe.
4. The relationships between incidence of bruising and several variables associated with the flock and the environment were examined using regression analysis. The factors shown to have a significant influence on the incidence of bruising were: the age and mean weight of the flock, and the temperature and humidity on the day of processing. 相似文献