Previous experiments with a sheep farm grazing
model suggested a weakness in assumptions
concerning pasture senescence and disappearance
rates which was influencing the quantity and more
importantly quality of pasture on offer and hence
animal performance. Data from the Winchmore
Research Station describing pasture masses and
the amount of dead material in irrigated swards
over several years have been used to derive joint
estimates of growth and senescence rates and
produced patterns similar to the few data available
in the literature. Subjective estimates were made
of likely differences in senescence between dryland
and irrigated conditions and the model used to
simulate the implications of these assumptions.
Results demonstrate the sensitivity of animal
performance to assumptions about the senescence
and disappearance rates of pasture, particularly in
the dryland situation where previously unrealistically
high levels of performance were reduced
closer to expected levels. This reinforces the
desirability of collecting data on dead material in
trials involving pasture measurements. Pasture
production, percentage harvested and animal
performance estimates from the model are
presented.[Show full abstract]
![[PDF]](/themes/LURA/images/mimes/b_pdf.png "PDF file"){kind=small}
