Publications by authors named "N E Calatayud"

The Southern Rocky Mountain boreal toad (Anaxyrus boreas boreas) depends on both the rearing of wild-collected egg masses and a long-standing conservation breeding program (CBP), the latter of which heavily relies on assisted reproductive technologies (ARTs) to support wild populations. Achieving consistent reproductive success in the CBP, however, remains a significant challenge. Natural breeding has not led to a sustained increase in reproductive capacity, prompting the exploration of exogenous hormone treatments as an alternative strategy.

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As sperm cryopreservation and other assisted reproductive technologies (ARTs) advance in common amphibian species, focus on applying non-lethal sperm collection methods to the conservation and genetic management of threatened species is imperative. The goal of this study was to examine the application of logistically practical ART protocols in a threatened frog (Litoria aurea). First, we tested the efficacy of various concentrations of human chorionic gonadotropin (hCG) (20, 40 IU/g bodyweight) and Gonadotropin releasing hormone antagonist (0.

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The cryopreservation and storage of gametes (biobanking) can provide a long-term, low-cost option for the preservation of population genetic diversity and is particularly impactful when applied to manage selective breeding within conservation breeding programs (CBPs). This study aimed to develop a sperm cryopreservation protocol for the critically endangered Booroolong frog () to capture founder genetics within the recently established (est. 2019) CBP for this species.

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Article Synopsis
  • * A study aimed to optimize sperm production through hormonal stimulation, testing various hormone treatments to establish a reliable collection protocol for reproduction.
  • * Results showed that a specific hormone (4 µg/gbw GnRH) produced the best sperm quality and concentration, while others like hCG were less effective, revealing notable characteristics of the sperm’s shape and structure.
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Objective: Arterial thrombosis may be initiated by endothelial inflammation or denudation, activation of blood-borne elements or the coagulation system. Tissue factor (TF), a central trigger of the coagulation cascade, is regulated by the pro-inflammatory NF-κB-dependent pathways. Sirtuin 6 (SIRT6) is a nuclear member of the sirtuin family of NAD-dependent deacetylases and is known to inhibit NF-κB signaling.

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