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Total viable counts at 20 and 37 °C and levels of coli‐aerogenes bacteria obtained from the rinsing of whole carcasses were reduced by more than 90% during chilling. Results obtained both with and without the use of chlorination compared favourably with those claimed for other chilling systems. It was concluded that the main effect of chlorination in the chillers was to destroy organisms washed from the carcasses, thus avoiding recontamination.
A comparison of two different sampling methods showed that maceration of neck‐skin usually gave higher counts of both faecal and spoilage bacteria after chilling than the rinsing of whole carcasses. 相似文献
The lifespan of erythrocytes using 75selenmethionine was 155 ± 10 days and 148 ± 7.8 days using tritiated diisopropylfluorophosphate. There was no significant difference at the 10% level between the lifespans, using these labels. The uptake of radioselenium into erythrocytes reached a mean maximum of 11.5% at 82 ± 18.9 days after injection of the label. There was an elution of from 17.6% of the injected dose of tritium label down to 7.5% eight days after injection of this isotope. From this study both of these labels appear to be satisfactory for determining the erythrocyte lifespan of the horse.
The mean time of the curve of mean radioselenium activity of peripheral blood leukocytes for the three horses was 5.54 days and the lifespan of these cells was seven days. The mean lifespan of peripheral blood leukocytes of the three horses after in vivo labelling with tritiated diisopropylfluorophosphate was 17.3 hours. No specific labelling was found in bone marrow or peripheral blood cells at this level of tritium labelling by dipping emulsion autoradiography.
The mean lifespan of equine platelets for three horses using radioselenomethionine was 9.2 days and the mean lifespan of equine platelets using tritiated diisopropylfluorophosphate was 6.6 days in a group of three horses.
相似文献Both for comparisons of leaf areas before defoliation, and for comparisons of leaf areas removed by defoliation, very highly significant relationships were found between estimates by the two methods. In five out of six cases the airflow-planimeter estimates of leaf area became greater than those from the inclined point quadrat as sward leaf area increased.
It is suggested that the major factor responsible for departure from complete agreement between the methods is a difference in leaf areas actually measured by the two methods; in addition, there was some indication of operator error with the inclined point quadrat. The results indicated that these factors were not greatly influenced by leaf canopy arrangement. 相似文献