The climatic drivers of long-term population changes in rainforest montane birds.

Climate-driven biodiversity erosion is escalating at an alarming rate. The pressure imposed by climate change is exceptionally high in tropical ecosystems, where species adapted to narrow environmental ranges exhibit strong physiological constraints. Despite the observed detrimental effect of climate change on ecosystems at a global scale, our understanding of the extent to which multiple climatic drivers affect population dynamics is limited. Here, we disentangle the impact of different climatic stressors on 47 rainforest birds inhabiting the mountains of the Australian Wet Tropics using hierarchical population models. We estimate the effect of spatiotemporal changes in temperature, precipitation, heatwaves, droughts and cyclones on the population dynamics of rainforest birds between 2000 and 2016. We find a strong effect of warming and changes in rainfall patterns across the elevational-segregated bird communities, with lowland populations benefiting from increasing temperature and precipitation, while upland species show an inverse strong negative response to the same drivers. Additionally, we find a negative effect of heatwaves on lowland populations, a pattern associated with the observed distribution of these extreme events across elevations. In contrast, cyclones and droughts have a marginal effect on spatiotemporal changes in rainforest bird communities, suggesting a species-specific response unrelated to the elevational gradient. This study demonstrated the importance of unravelling the drivers of climate change impacts on population changes, providing significant insight into the mechanisms accelerating climate-induced biodiversity degradation.

Transcriptome Signature of Immature and In Vitro-Matured Equine Cumulus-Oocytes Complex.

Maturation is a critical step in the development of an oocyte, and it is during this time that the oocyte advances to metaphase II (MII) of the meiotic cycle and acquires developmental competence to be fertilized and become an embryo. However, in vitro maturation (IVM) remains one of the limiting steps in the in vitro production of embryos (IVP), with a variable percentage of oocytes reaching the MII stage and unpredictable levels of developmental competence. Understanding the dynamics of oocyte maturation is essential for the optimization of IVM culture conditions and subsequent IVP outcomes. Thus, the aim of this study was to elucidate the transcriptome dynamics of oocyte maturation by comparing transcriptomic changes during in vitro maturation in both oocytes and their surrounding cumulus cells. Cumulus-oocyte complexes were obtained from antral follicles and divided into two groups: immature and in vitro-matured (MII). RNA was extracted separately from oocytes (OC) and cumulus cells (CC), followed by library preparation and RNA sequencing. A total of 13,918 gene transcripts were identified in OC, with 538 differentially expressed genes (DEG) between immature OC and in vitro-matured OC. In CC, 13,104 genes were expressed with 871 DEG. Gene ontology (GO) analysis showed an association between the DEGs and pathways relating to nuclear maturation in OC and GTPase activity, extracellular matrix organization, and collagen trimers in CC. Additionally, the follicle-stimulating hormone receptor gene (FSHR) and luteinizing hormone/choriogonadotropin receptor gene (LHCGR) showed differential expressions between CC-MII and immature CC samples. Overall, these results serve as a foundation to further investigate the biological pathways relevant to oocyte maturation in horses and pave the road to improve the IVP outcomes and the overall clinical management of equine assisted reproductive technologies (ART).

Now is the Time for a Postracial Medicine: Biomedical Research, the National Institutes of Health, and the Perpetuation of Scientific Racism.

The consideration of racial differences in the biology of disease and treatment options is a hallmark of modern medicine. However, this time-honored medical tradition has no scientific basis, and the premise itself, that is, the existence of biological differences between the commonly known races, is false inasmuch as races are only sociocultural constructions. It is time to rid medical research of the highly damaging exercise of searching for supposed racial differences in the biological manifestations of disease. The practice not only condoned but required by the National Institutes of Health (NIH) of utilizing racial identification as a demographic characteristic with assumed biological implications is at best badly flawed, and at worst unintentionally contributes to perpetuating the fallacy of natural differences between persons of different skin color, which has been used in the past to advance the cause of racial discrimination.

Embryo Pulsing: Repeated Expansion and Contraction of In Vivo and In Vitro Equine Blastocysts.

Morphokinetic evaluation of embryo development has allowed the discovery of events occurring during blastulation. Here, we describe equine embryo pulsing, determined as continued expansion and contraction of both in vivo and in vitro produced blastocysts. Using time-lapse imaging, we demonstrated that pulsing starts during early blastocyst development of in vitro-produced embryos in horses. The median time for a complete contraction was 0.22h (0.08h-2h; min-max) where embryos reduced their sizes around 12.0% (median; 2.3%-27.0%) and the median time for an expansion was 3.3h (0.75-9.0h) where embryo re-expanded around 16.9% (3.2%-42.8%). We also found that pulsing can be observed in in vivo-produced embryos obtained from mares 6.5 days after ovulation and continues during the expansion of the blastocysts. Even though its exact mechanism remains unknown, studies in human IVF suggest that the pulsing of embryos is associated with embryo quality and implantation rates. Thus, further investigations regarding this event in equine in vitro production procedures are warranted. Additionally, the pulsing in the in vivo-produced embryos could explain the diverse morphology occasionally observed in the collected or shipped embryos. Future studies are necessary to understand the underlying mechanism of pulsing and its association with embryo quality and embryo transfer outcome.

Sperm parameters in the Great Dane: Influence of age on semen quality.

Not all sires have sperm suitable for chilled or frozen storage, and success in artificial insemination (AI) varies highly among individual dogs and breeds. Fertilizing potential is further complicated as sperm quality declines with the aging process. Due to the rapidity of aging and senescence in large breed dogs, associated health and fertility changes may be observed over a shorter period, though this period remains undefined for any breed. Working with a population of purebred Great Danes (GD), our aims were (1) to characterize the distribution of a series of sperm parameters, (2) to distinguish sources of variation in sperm quality within this rapidly aging breed, and (3) to identify changes in sperm quality that may accompany aging. Ejaculates collected from young, middle-aged, and senior Great Dane dogs (n = 50) were evaluated for semen volume, total sperm number and viability, and reactive oxygen species (ROS), in addition to sperm morphology and kinematic parameters. Total testicular volume was also determined using ultrasonography. Testicular volume was not a predictor of sperm production in the GD, however, significant differences between coat colors were identified. Age was negatively associated with total motility, progressive motility, and amplitude of lateral head displacement (ALH) (p < .05). We identified significant relationships between GD male age and TM, PM, and immotility with -9.9%, -9.0%, and +8.3% change per year of age, respectively, which support the anecdotal reports of decline of the fertility with the advance of age in this breed. Sperm of younger GD dogs aged 12 ≤ x < 24 months had significantly higher TM, PM, ALH, and nonlinear motility (p < .05) than older dogs (x ≥ 48 months). High ROS levels were positively associated with TM and PM, average pathway distance (DAP) and straight line distance (DSL), average pathway velocity (VAP), straight line velocity (VSL), and the presence of hairpin tails (p < .05). While age and ROS have significant influences on sperm parameters in the GD, the influence of selection for breed specific phenotypes could help explain the functional significance of the diversity among GD males.

Effect of pentobarbital as a euthanasia agent on equine in vitro embryo production.

Postmortem and pre-euthanasia oocyte retrieval provides the last opportunity to preserve the genetic material in mares. Pentobarbital (PB) is the most common euthanasia agent; however, its effect on the developmental competence of oocytes has not been determined. Here, we evaluated the concentration of PB in equine follicular fluid (FF) and investigated its effect on the developmental competence of oocytes using a bovine IVF model to overcome the low availability of equine oocytes. The concentration of PB was measured by gas-chromatography/mass-spectrometry in FF collected from mare ovaries immediately after euthanasia (n = 10), 24 h post-euthanasia (n = 10), and from the ovaries collected by ovariectomy (negative control; n = 10). The serum concentration of PB was also evaluated as a positive control. PB was detected in all FF samples with an average concentration of 56.5 µg/ml. Next, bovine cumulus-oocyte complexes (COC) were held in holding media with PB for 6 h at 60 µg/ml (H60, n = 196), 164 µg/ml (H164, n = 215) or without PB (control; n = 212). After holding, the oocytes were matured and fertilized in vitro, followed by in vitro culture to the blastocyst stage. The cumulus expansion grade, cleavage rate, blastocyst rate, embryo kinetic rate and the blastocyst cell numbers were compared among the experimental groups of bovine COC. Higher rates of Grade 1 cumulus expansion were found in controls (54%, 32-76%; median, min-max) in comparison to H60 and H164 (24%,11-33% and 13%, 8-44%; P < 0.001). The cleavage rate was higher in the controls than in H164 (64% vs. 44%; P < 0.01). Blastocyst rates (blastocyst/cleaved oocytes) and total cell number were not different among the groups (control 29%, H60 25%, and H164 24%). In a preliminary study, equine oocytes (n = 28) were exposed to PB in vitro for 6 h followed by intracytoplasmic sperm injection (ICSI) and in vitro embryo production. Exposed oocytes showed a numerically lower maturation rate (43% Vs 52%; P > 0.05) in comparison to the laboratory-established rate during the same timepoints. Overall, we showed that PB reaches the FF immediately after euthanasia, exposing oocytes to this drug. This exposure affected cumulus expansion and cleavage rates in a bovine model, suggesting initial damage caused by PB that may not completely impede the formation of embryos, although lower overall embryo numbers might be obtained.

Effect of Transvaginal Aspiration of Oocytes on Blood And Peritoneal Fluid Parameters in Mares.

Transvaginal aspiration of oocytes (TVA) is a commonly used clinical procedure to obtain oocytes for in vitro production of embryos in horses. The goal of this study was to evaluate the effect of the TVA procedure on blood and peritoneal parameters, and to investigate the association of these findings with variables such as use of antibiotics, number of ovarian punctures, and length of the procedure. Physical examination was performed and blood and peritoneal fluid were obtained from 14 mares before they underwent TVA and the same parameters were assessed 24 hours after the procedure. On examination, 13/14 mares remained clinically healthy after the procedure. One mare developed low-grade fever, transient anorexia and mild colic that resolved within 12 hours post-TVA. The use of antibiotics, length of procedure and number of ovarian punctures did not have an effect on the measured parameters. All the mares presented significant changes in the leukogram, but these mostly remained within normal reference range values. The peritoneal parameters were also consistently affected after TVA. A significant post-TVA increase in lactate, total protein, and peritoneal neutrophil count was observed in peritoneal fluid. Peritoneal lactate level was elevated above baseline physiological levels in more than 50% of the mares. Results from this study indicate that there is an expected degree of inflammation after TVA procedures and peritoneal fluid parameters could be successfully used to monitor inflammation in the early stages.

Long-term changes in populations of rainforest birds in the Australia Wet Tropics bioregion: A climate-driven biodiversity emergency.

Many authors have suggested that the vulnerability of montane biodiversity to climate change worldwide is significantly higher than in most other ecosystems. Despite the extensive variety of studies predicting severe impacts of climate change globally, few studies have empirically validated the predicted changes in distribution and population density. Here, we used 17 years (2000-2016) of standardised bird monitoring across latitudinal/elevational gradients in the rainforest of the Australian Wet Tropics World Heritage Area to assess changes in local abundance and elevational distribution. We used relative abundance in 1977 surveys across 114 sites ranging from 0-1500m above sea level and utilised a trend analysis approach (TRIM) to investigate elevational shifts in abundance of 42 species. The local abundance of most mid and high elevation species has declined at the lower edges of their distribution by >40% while lowland species increased by up to 190% into higher elevation areas. Upland-specialised species and regional endemics have undergone dramatic population declines of almost 50%. The "Outstanding Universal Value" of the Australian Wet Tropics World Heritage Area, one of the most irreplaceable biodiversity hotspots on Earth, is rapidly degrading. These observed impacts are likely to be similar in many tropical montane ecosystems globally.

[Amniotic band sequence and bilateral choanal atresia: a case report]. / Secuencia de bridas amnióticas y atresia bilateral de coanas: reporte de un caso.

Amniotic band sequence (ABS) is a group malformation that mainly affects limbs; clinically, constriction rings and lymphedema of the fingers, arms and legs, acrosyndactyly and pseudosyndactyly are observed; also there is congenital amputation of limbs due to distal swelling. Less frequently, craniofacial and trunk involvement are reported in some patients. Etiology is still unknown and most cases are isolated. In this report we present the case of a 45-day-old male with diagnosis of SBA and bilateral choanal atresia as attached finding, and review possible causes of SBA and associated alterations.

Secuencia de bridas amnióticas y atresia bilateral de coanas: reporte de un caso / Amniotic band sequence and bilateral choanal atresia: a case report

La secuencia de bridas amnióticas (SBA) es un grupo de malformaciones de tipo disruptivo que afecta principalmente las extremidades; clínicamente, se observan anillos de constricción y linfedema en dedos, brazos y piernas; pseudosindactilias y acrosindactilias; además, existe amputación congénita de las extremidades por tumefacción distal; en algunos pacientes se han comunicado, con menor frecuencia, alteraciones craneofaciales y del tronco. La etiología es aún desconocida y la mayoría de los casos son aislados. En este informe presentamos el caso de un paciente masculino, de 45 días de nacido, con diagnóstico de SBA y atresia bilateral de coanas como hallazgo adjunto; se revisan las posibles causas del SBA y las alteraciones asociadas.

Amniotic band sequence (ABS) is a group malformation that mainly affects limbs; clinically, constriction rings and lymphedema of the fngers, arms and legs, acrosyndactyly and pseudosyndactyly are observed; also there is congenital amputation of limbs due to distal swelling. Less frequently, craniofacial and trunk involvement are reported in some patients. Etiology is still unknow and most cases are isolated. In this report we present the case of a 45-day-old male with diagnosis of SBA and bilateral choanal atresia as attached fnding, and review possible causes of SBA and associated alterations.