Effect of glutathione on the quality of frozen buck semen

Ejaculates (30) collected twice weekly from five Beetal bucks were used to study the effect of addition of 0 (control), 4 mM, 6 mM and 8 mM glutathione on the quality of frozen Beetal buck semen by split sample technique. After removal of seminal plasma, the semen was primarily extended with Tris extender (1: 5) considering the volume of semen prior to removal of seminal plasma and then split into 4 parts and finally extended with equal volume of Tris extender that rose the extension rate to 1: 10. The mean percentage of sperm motility, live sperm, live intact acrosome, HOST-reacted sperm was significantly higher in Tris extender containing 4 mM glutathione than that containing 6 mM, 8 mM glutathione and control. The release of ALT and AST from post-thaw spermatozoa was also the lowest in semen containing 4mM concentration of glutathione. Based on post-thaw sperm motility, live sperm, live intact acrosome, HOST-reacted sperm, and ALT and AST release, addition of 4 mM glutathione in Tris extender was superior to 6 mM, 8 mM and 0 mM (control). It was concluded that glutathione at 4 mM could be used as an antioxidant in Tris for cryopreservation of Beetal buck semen which could provide a better environment in protecting the functional capacity of spermatozoa

Ecoacoustics and multispecies semiosis: naming, semantics, semiotic characteristics, and competencies

Biosemiotics to date has focused on the exchange of signals between organisms, in line with bioacoustics; consideration of the wider acoustic environment as a semiotic medium is under-developed. The nascent discipline of ecoacoustics, that investigates the role of environmental sound in ecological processes and dynamics, fills this gap. In this paper we introduce key ecoacoustic terminology and concepts in order to highlight the value of ecoacoustics as a discipline in which to conceptualise and study intra- and interspecies semiosis. We stress the inherently subjective nature of all sensory scapes (vivo-, land-, vibro- and soundscapes) and propose that they should always bear an organismic attribution. Key terms to describe the sources (geophony, biophony, anthropophony, technophony) and scales (sonotopes, soundtopes, sonotones) of soundscapes are described. We introduce epithets for soundscapes to point to the degree to which the global environment is implicated in semiosis (latent, sensed and interpreted soundscapes); terms for describing key ecological structures and processes (acoustic community, acoustic habitat, ecoacoustic events) and examples of ecoacoustic events (choruses and noise) are described. The acoustic eco-field is recognized as the semiotic model that enables soniferous species to intercept core resources like food, safety and roosting places. We note that whilst ecoacoustics to date has focused on the critical task of the development of metrics for application in conservation and biodiversity assessment, these can be enriched by advancing conceptual and theoretical foundations. Finally, the mutual value of integrating ecoacoustic and biosemiotics perspectives is considered