Real-time ultrasound imaging for predicting ovine fetal age.

Fetal head width and thoracic depth were observed via real-time ultrasound imaging in 12 single-, 12 twin- and 4 triplet-bearing BooroolaxSouth Australian Merino ewes at weekly intervals during mid pregnancy. Fetal age varied by a maximum of 24 h. Relationships between fetal age and the linear measures (head width, thoracic depth) were determined within litter size categories, using both linear and quadratic terms.

Grazing impact in relation to livestock watering points.

Animals use and impact on habitats unevenly. A prime example is the 'piosphere', the zone of ecological impact focused around a livestock watering point, particularly in dry areas. The piosphere provides a good context for studying the ecological effects of large herbivores, and for applying ecological information to land management.

The role of CO uptake by roots and CAM in acquisition of inorganic C by plants of the isoetid life-form: a review, with new data on Eriocaulon decangulare L.

The isoetid life-form was originally defined on morphological grounds; subsequent physiological investigations showed that all of the isoetids examined took up a large fraction of the inorganic C fixed in their leaves from the root medium under natural conditions, and that some of them carried out much of their assimilation of inorganic C via a CAM-like mechanism. Root-dominated uptake of inorganic C appeared to be unique to, and ubiquitous in, the isoetids. I However, a large capacity for CAM-like metabolism in submerged vascular plants is not universal in isoetids, nor is it restricted to this life-form, being also found in Crassulaa aquatica.