5. DISCUSSION
5.8 CONCLUSIONS
1 . The use of monocultures of pasture species is a useful p rocedu re in d etermination of g razing preferences of cattle.
2 . G razing cattle p referred mixed d iets , with partial preference for legumes over g rass with an average ratio of about 70:30 respectively. This p reference varied between seasons and was higher in the summer compared to autumn.
3 . Vertical availability (e.g. height and BD) of herbage influenced p reference of cattle. As harvesting the preferred species became more d ifficult (decreasing heig ht) partial preference declined . However, the effect of height may be confounded with that of BD.
4. Preference between two legumes (e.g . lotus and red clover) was weaker than that observed between legume-grass with an average p a rtial p reference
of 55 % i n favour of the lotus over red clover. Seasonal variation ind icates
that animals g razed selectively for lotus in summer but not in a utu m n .
5 . Cattle responded to species choice by adjusting the time spent g razing . This may be related to different rates of intake between herbage species.
6. There may be potential benefits to animal performance by offering herbage species in propo rtion to those preferred by the animals, as indicated by the trend to decrease total g razing time with increases in availability of a preferred species. The potential benefits need to be eval uated in terms of animal performance under long-term g razing trials which m ay add further information to the current knowledge on dietary preferences of g razing cattle.
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