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2. Neither pelleting diets nor heat processing the beans by autoclaving proved beneficial. A continuous‐flow process for infra‐red heating of the seeds at 150 °C for 70 s followed immediately by flaking (micronisation) gave inconsistent results.
3. Beans having a white skin with associated low tannin content, did not support significantly higher egg production than did a normal brown‐skinned bean, thus indicating that tannin was not the main anti‐nutritive factor.
4. A cotyledon fraction, obtained by mechanical removal of the tannin‐containing skin from brown beans, did not support higher egg production than did the whole bean, and the corresponding brown‐skin fraction did not reduce egg production when substituted for cereal in the control diet. Again this indicated that tannin was not implicated. 相似文献
METHODS: Ninety lambs, aged approximately 6 months, were grazed on plots of perennial ryegrass infected with either AR98 endophyte (containing lolitrem B), standard endophyte (containing lolitrem B and ergovaline) or no endophyte, for up to 42 days from 2 February 2010. Ten lambs were grazed on three replicate plots per cultivar. Herbage samples were collected for alkaloid analysis and lambs were scored for ryegrass staggers (scores from 0–5) weekly during the study. Any animal which was scored ≥4 was removed from the study.
RESULTS: Concentrations of lolitrem B did not differ between AR98 and standard endophyte-infected pastures during the study period (p=0.26), and ergovaline was present only in standard endophyte pastures. Ryegrass staggers was observed in sheep grazing both the AR98 and standard endophyte plots, with median scores increasing in the third week of the study. Prior to the end of the 42-day grazing period, 22 and 17 animals were removed from the standard endophyte and AR98 plots, respectively, because their staggers scores were ≥4. The cumulative probability of lambs having scores ≥4 did not differ between animals grazing the two pasture types (p=0.41).
CONCLUSIONS AND CLINICAL RELEVANCE: There was no evidence for ergovaline increasing the severity of ryegrass staggers induced by lolitrem B. In situations where the severity of ryegrass staggers appears to be greater than that predicted on the basis of concentrations of lolitrem B, the presence of other tremorgenic alkaloids should be investigated. 相似文献