METHODS AND RESULTS: Four rounds of Cell-SELEX were performed, where the DNA aptamer library was incubated with X-sorted semen. Subsequently, affinity-depicting aptamers were sequenced. Fourteen out of thirty-four identified sequences were tested for specificity towards X-sorted sperm. The magnetic bead-based experiment revealed that the aptamers interacted preferentially with the acrosome region (sperm head) of sperm. We investigated the specificity of aptamers for X-spermatozoa by conducting real-time PCR assays targeting sex-specific genes. Aptamers X8, X19, X22 & X27 exhibited higher affinity for X-sorted sperm than Y in bovine semen. Western blot analysis showed an interaction between the aptamer and sperm protein at 35 kDa. The results underwent further analysis using in-gel mass spectrometry (MS) that predicted SPACA1 protein as the potential/putative aptamer binding protein on the sperm surface. Competitive western blot further confirmed aptamers' differential specificity for X-sperm.
CONCLUSIONS: The current work helps in creating new knowledge for the separation of Y-chromosome-bearing sperm from XY sperm populations that have the potential to produce good-quality cattle (cows). The work also generates proof of concept (POC) of using aptamers, which is cost-effective and could be used in sorting sex-specific spermatozoa without causing any ill effect on sperm.
OBJECTIVES: To evaluate the relationship between plasma [FRA] and glucose concentration ([gluc]) as well as indices of energy balance during early lactation in dairy cattle, and to characterize the influence of plasma total protein concentration ([TP]) and albumin concentration ([albumin]) on [FRA].
ANIMALS: Convenience sample comprising 103 periparturient Holstein-Friesian cattle.
METHODS: Plasma [gluc], [TP], [albumin], and other clinicopathologic indices of energy status were determined periodically from Day 4 postpartum. Body condition score (BCS) was assessed, and backfat thickness (BFT) and longissimus dorsi muscle thickness (LDT) were measured ultrasonographically. Plasma [FRA] was measured at approximately 28 days postpartum. Associations between plasma [FRA] and study variables were evaluated using Spearman's rho and stepwise forward linear regression. Statistical significance was declared at P
METHODOLOGY: We examined cattle and goats reared around Pteropus bat roosts in human NiV outbreak areas. We also tested pig sera collected under another study focused on Japanese encephalitis.
PRINCIPAL FINDINGS: We detected antibodies against NiV glycoprotein in 26 (6.5%) cattle, 17 (4.3%) goats and 138 (44.2%) pigs by a Luminex-based multiplexed microsphere assay; however, these antibodies did not neutralize NiV. Cattle and goats with NiVsG antibodies were more likely to have a history of feeding on fruits partially eaten by bats or birds (PR=3.1, 95% CI 1.6-5.7) and drinking palmyra palm juice (PR=3.9, 95% CI 1.5-10.2).
CONCLUSIONS: This difference in test results may be due to the exposure of animals to one or more novel viruses with antigenic similarity to NiV. Further research may identify a novel organism of public health importance.