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Three ejaculates from each of eight stallions were initially centrifuged in INRA 96 extender and spermatozoal pellets were resuspended in a milk/egg yolk-based freezing extender or an egg yolk-based freezing extender. Extended semen was exposed to a fast pre-freeze cooling rate (FAST -semen immediately subjected to cryopreservation) or a slow pre-freeze cooling rate (SLOW -semen pre-cooled at a controlled rate for 80 minutes prior to cryopreservation). After thawing, semen was diluted in initial freezing medium (FM) or INRA 96 prior to analysis of 9 experimental endpoints: total motility (MOT; %), progressive motility (PMOT; %), curvilinear velocity (VCL; µm/sec), average-path velocity (VAP; µm/sec), straight-line velocity (VSL; µm/sec), linearity (LIN; %), intact acrosomal and plasma membranes (AIVIAB; %), intact acrosomal membranes (AI; %), and intact plasma membranes (VIAB; %). Mean values for these endpoints were higher following spermatozoal exposure to a slow pre-freeze cooling period, regardless of freezing extender type (P<0.05). The effects of pre-freeze cooling rate on MOT, AIVIAB, AI, and VIAB were more pronounced in spermatozoa cryopreserved in MF extender, as compared to LE extender. Within treatment groups SLOW and FAST, mean MOT, AIVIAB, AI, and VIAB were higher (P<0.05) for spermatozoa cryopreserved in LE extender, as compared to MF extender.

Cadmium (Cd) is a non‐essential toxic heavy metal for most organisms. Accumulation of Cd is toxic to plants, and it also causes serious health concerns in humans as plants are the major staples in human diet. In A. thaliana, cadmium is mainly accumulated in the roots suggesting that root‐to‐shoot Cd translocation is restricted at the xylem loading. Up to date, two members of HEAVY METAL P1B‐ATPase (HMA) family of transporters, namely HMA2 and HMA4, and some YSL transporters have been shown to be responsible for Cd loading into the xylem. Here we present data suggesting CADMIUM DETERMINANT 1 (CDM1) as a previously uncharacterized putative heavy‐metal transporter in plants. Expression of CDM1 was induced under Cd treatment in wild‐type seedling roots. Elemental analysis of two alleles of cdm1 mutant by ICP‐MS showed that the mutants accumulated less Cd and Zn both in shoots and roots after Cd treatment. In addition, root growth of cdm1 mutants showed higher tolerance to Cd toxicity. These data suggest that CADMIUM DETERMINANT 1 (CDM1) functions in Cd distribution in plants. Interestingly, preliminary confocal microscopy analyses of seedlings overexpressing CDM1:GFP indicated that CDM1 localized to the plastids. Further characterization of CDM1:GUS and CDM1 overexpression lines are in progress. Grant Funding Source: Supported by NSF‐MCB 0950459