Measurement of light penetration through a simulated merino fleece

The degree of light penetration along the length of the fibre of a simulated Merino fleece was measured using a fibre optic probe to investigate the relationship between light exposure and photodamage to the wool fibre. The percentage of the total direct sunlight that reached the base of the 100-mm long, simulated, closed Merino fleece was ~1% and the section of the fibre from the root to 60 mm from the root was protected from exposure. The light intensity at the base of the fibre was increased to 2% when the density of the simulated fleece was halved. Wool was scoured and the yellowness and intensity of methylene blue staining was measured to estimate the extent of damage to wool staples.

The effect of plant tissue and vaccine formulation on the oral immunogenicity of a model plant-made antigen in sheep

Antigen-specific antibody responses against a model antigen (the B subunit of the heat labile toxin of enterotoxigenic Escherichia coli, LTB) were studied in sheep following oral immunisation with plant-made and delivered vaccines. Delivery from a root-based vehicle resulted in antigen-specific immune responses in mucosal secretions of the abomasum and small intestine and mesenteric lymph nodes. Immune responses from the corresponding leaf-based vaccine were more robust and included stimulation of antigen-specific antibodies in mucosal secretions of the abomasum. These findings suggest that oral delivery of a plant bioencapsulated antigen can survive passage through the rumen to elicit mucosal and systemic immune responses in sheep. Moreover, the plant tissue used as the vaccine delivery vehicle affects the magnitude of these responses.