El pelícano blanco americano (pelecanus erythrorhynchus) en colombia, con comentarios sobre los efectos de los huracanes en el caribe

Presentamos un registro fotográfico del Pelicano Blanco Americano (Pelecanus erythrorhynchus) en un manglar de la isla de San Andrés, en el Caribe colombiano, con lo cual se confirma la presencia de esta especie en Colombia. Adicionalmente discutimos el posible efecto de los huracanes del Caribe en la dispersión de esta especie y los efectos que estas catástrofes naturales pueden tener en la conservación de la avifauna del Archipiélago de San Andrés y Providencia

Seminal plasma proteins modify the distribution of sperm subpopulations in cryopreserved semen of rams with lesser fertility

P. 44-50Any physiological mechanism involved in sperm selection and semen improvement has effects on heterogeneous sperm populations. This is mainly due to the fact that sperm populations within a single ejaculate have considerable heterogeneity for many variables, such as motility which is meaningful in terms of understanding how some sperm cells possess fertility advantages as compared with other cells. In the present research, initially there was a multivariate and clustering analysis used to assess sperm motility data from cryopreserved ram semen to identify subpopulations and compare the distribution of these clusters between rams with lesser and greater fertility. There were four classifications made of sperm subpopulations (clusters): CL1 fast/linear/progressive sperm; CL2 fast/non-linear sperm; CL3 very fast/linear sperm with vigorous beating and CL4 slow/non-linear sperm. Rams with greater fertility had a lesser proportion of sperm considered as “hyperactivated” (CL2) and a greater proportion of slow and non-linear sperm (CL4) than sperm of rams with lesser fertility. In addition, the effects were assessed for the capacity of seminal plasma (SP) and interacting SP proteins (iSPP) that were present during different seasons of the year to improve the distribution of sperm within subpopulations of semen from rams with lesser fertility. The iSPP and SP were obtained by artificial vagina (AV) and electroejaculation (EE) during breeding and non-breeding seasons and added to thawed semen. All the aggregates had a significant effect on the distribution of sperm subpopulations and effects differed among seasons of the year and depending on collection method used. Even though, future studies are needed to assess the contribution of each subpopulation on ram sperm fertility, it is important that a multivariate analysis be used to evaluate the effect of a treatment on sperm quality variables.S

Seminal plasma proteins interacting with sperm surface revert capacitation indicators in frozen-thawed ram sperm

P. 35-41This study was conducted to evaluate the effects of interacting seminal plasma proteins (iSPP) obtained by AV or EE on frozen-thawed ram sperm in order to test the hypothesis whether this fraction could be sufficient to emulate the effect of complete seminal plasma (SP). Additionally, we evaluated whether these proteins have a differential effect between spermatozoa from high and low fertility rams and between breeding and non-breeding seasons. We assessed sperm motility, quality parameters (intracellular reactive oxygen species, membrane fluidity, plasma membrane permeability and mitochondrial activity) and capacitation status. The main findings from this work were: i) iSPP had no effect on sperm motility, whereas SP (AV or EE) addition produced the highest values of total motility (74.13 ± 2.99 and 72.27 ± 2.99 for AV and EE, respectively) and progressive motility (64.97 ± 2.64 and 63.73 ± 2.64 for AV and EE, respectively); ii) iSPP had no effect on sperm quality parameters (p > 0.05), but whole SP improved all parameters evaluated. Moreover, SP collected by AV yielded significantly higher viability (44.60 ± 2.87) and sperm with stable plasma membrane (44.56 ± 2.49) comparing with the addition of SP collected by EE (35.80 ± 2.47 and 36.67 ± 1.71, respectively); iii) iSPP and SP collected by EE, but not by AV, reverted molecular signals of capacitation as protein tyrosine phosphorylation caused by freezing temperatures; iv) there were no effects of fertility or season in sperm quality parameters evaluated. This study demonstrated that, although the iSPP have a clear decapacitating effect, including the ability to revert cryo-capacitation indicators, they are not sufficient to emulate the effects of complete SP regarding sperm functional parameters.S

Quality Assessment of Photoplethysmography Signals For Cardiovascular Biomarkers Monitoring Using Wearable Devices

Photoplethysmography (PPG) is a non-invasive technology that measures changes in blood volume in the microvascular bed of tissue. It is commonly used in medical devices such as pulse oximeters and wrist worn heart rate monitors to monitor cardiovascular hemodynamics. PPG allows for the assessment of parameters (e.g., heart rate, pulse waveform, and peripheral perfusion) that can indicate conditions such as vasoconstriction or vasodilation, and provides information about microvascular blood flow, making it a valuable tool for monitoring cardiovascular health. However, PPG is subject to a number of sources of variations that can impact its accuracy and reliability, especially when using a wearable device for continuous monitoring, such as motion artifacts, skin pigmentation, and vasomotion. In this study, we extracted 27 statistical features from the PPG signal for training machine-learning models based on gradient boosting (XGBoost and CatBoost) and Random Forest (RF) algorithms to assess quality of PPG signals that were labeled as good or poor quality. We used the PPG time series from a publicly available dataset and evaluated the algorithm s performance using Sensitivity (Se), Positive Predicted Value (PPV), and F1-score (F1) metrics. Our model achieved Se, PPV, and F1-score of 94.4, 95.6, and 95.0 for XGBoost, 94.7, 95.9, and 95.3 for CatBoost, and 93.7, 91.3 and 92.5 for RF, respectively. Our findings are comparable to state-of-the-art reported in the literature but using a much simpler model, indicating that ML models are promising for developing remote, non-invasive, and continuous measurement devices.Comment: 9 page

Lista de chequeo de las aves de Colombia: Una síntesis del estado del conocimiento desde Hilty & Brown

The taxonomy and knowledge of the distribution of Colombian avifauna has undergone great changes since the publication of “A Guide to the Birds of Colombia” by Hilty & Brown (1986) to the extent that we are unaware of how many and which species inhabit the Colombian territory. Here, we present a checklist of the birds of Colombia updated to August 2017 with a review of 340 references dealing with the distribution of Colombian birds. In sum, we report 1909 species for continental and insular Colombia, 216 of which have been added mainly since 1986. Although there are new data on distribution from 66% of the Colombian avifauna, most publications (87%) and new records (53%) are concentrated to the west of the Eastern cordillera (trans-Andean region). Based on the data we identify those regions of the country with knowledge gaps, which deserve more interest from researchers. Moreover, we encourage the ornithological community to publish their unpublished data and to improve the evidence supporting future new records for the country.La taxonomía y conocimiento de la distribución de la avifauna colombiana ha sufrido grandes cambios desde la publicación de “A Guide to the Birds of Colombia” por Hilty & Brown (1986), a tal punto que hoy no se sabe con precisión cuántas y cuáles especies de aves existen en el territorio colombiano. Presentamos la lista de chequeo de la avifauna de Colombia a agosto de 2017 con base en la revisión de 340 referencias relacionadas con la distribución de la avifauna colombiana. En total, reportamos 1909 especies de aves para el territorio continental e insular del país, de las cuales 216 han sido adicionadas principalmente a partir de 1986. Aunque existe información novedosa sobre distribución para cerca del 66% de la avifauna colombiana, la mayoría de las publicaciones (87%) y registros (53%) se concentran al occidente de la cordillera Oriental (región transandina). Con base en esta información identificamos aquellas áreas del país con vacíos de conocimiento que ameritan mayor interés por parte de los investigadores. Además, estimulamos a la comunidad ornitológica a publicar la información inédita represada, al igual que mejorar la evidencia que soporta los registros novedosos para el país

Aves del departamento del Valle del Cauca, Colombia

The avifauna of the department of Valle del Cauca, Colombia, has been one of the best studied biological groups in Colombia since the late 19th century. As a result of these information compilations, estimates of species richness range between 818 and 1025 species. We collected information on bird records from different sources and obtained a list of 989 confirmed bird species for the department and 13 species that were listed as potentially present. We found eight introduced species that have no published records or are anecdotal in Colombia. Future expeditions or investigations should focus on filling the information gaps on birds in the Garrapatas river canyon, the area south of Buenaventura and the Central mountain range.La avifauna del departamento del Valle del Cauca, Colombia, ha sido uno de los grupos biológicos mejor estudiados en Colombia desde finales del siglo XIX. Producto de estos ejercicios de compilación de información, los estimados de la riqueza de especies varían entre 818 y 1025 especies. Recopilamos información de registros de aves de diferentes fuentes y obtuvimos un listado de 989 especies de aves confirmadas para el departamento y 13 especies que fueron catalogadas como potencialmente presentes. Documentamos ocho especies introducidas que no tienen registros publicados o son anecdóticos en Colombia. Futuras expediciones o investigaciones deberían enfocarse en llenar los vacíos de información de aves que se concentran en el cañón del río Garrapatas, y el área al sur de Buenaventura y la cordillera Central

Removal of bacteria from boar semen using a low-density colloid

P. 272-278Antibiotics are added to semen extenders when preparing commercial semen doses for artificial insemination according to national and international guidelines. However, this addition of antibiotics represents non-therapeutic usage and could be contributing to the development of antibiotic resistance. Colloid centrifugation was shown to reduce the load of bacteria present in boar semen and was capable of removing all bacteria if performed directly after semen collection, albeit with some loss of spermatozoa. The present experiment was conducted with a low density colloid to investigate whether it was possible to separate all of the spermatozoa from seminal plasma i.e. without selection for robust spermatozoa, or whether this would have a detrimental effect on sperm quality. Ejaculates from nine boars were extended in Beltsville Thawing Solution without antibiotics and were transported to the laboratory for Single Layer Centrifugation (SLC) on modified Porcicoll i.e. at a low density (S). A further modification was that a sterile inner tube was included inside some of the 50 mL centrifuge tubes to facilitate harvesting of the sperm pellet (M). Aliquots of all samples (control, S and M) were cultured for bacterial quantification and identification using standard microbiological methods. Sperm quality was evaluated daily. Three of the C and M samples and five of the S samples did not contain any bacteria. Mean bacterial counts for the remaining samples (colony forming units/mL) were as follows: C 259 ± 216; S 30 ± 22; M 33 ± 15 (P < 0.01). Citrobacter spp., Staphylococcus simulans, Klebsiella variicola, Escherichia coli, Myroides odoratimimus, Proteus spp. and Enterococcus faecalis were identified in the control samples. There were marginal differences in sperm quality among treatments, with sperm velocity and linearity being higher in S and M samples than in C at all time points. However, sperm viability, capacitation and acrosome status were marginally better in controls than in S or M on day 0, but these differences disappeared during storage. Conclusions: centrifugation through a low density colloid can remove or reduce bacterial contamination in boar ejaculates without using antibiotics. Furthermore, it is possible to collect boar ejaculates without bacterial contamination by paying strict attention to hygiene.S

Melatonin receptors MT1 and MT2 are expressed in spermatozoa from several seasonal and nonseasonal breeder species

P. 1958-1968Melatonin is a ubiquitous and multipurpose molecule, and one of its roles is to regulate reproduction in some seasonal mammals. Our group has previously reported the variation in the melatonin levels in ram seminal plasma along the year and identified MT1 and MT2 receptors in ram spermatozoa. The objective of this study was to elucidate whether the presence of melatonin receptors (MT1 and MT2) in the sperm plasma membrane, and melatonin in the seminal plasma is related to seasonal breeding. For this purpose, the presence of melatonin receptors and the levels of melatonin in seminal plasma have been examined in several species: donkey and stallion as long-day breeders; red deer as a wild, short-day, highly seasonal breeder (epididymal spermatozoa); bull as a conventional nonseasonal breeder; boar as a seasonal breeder under management techniques; and dog as possible a seasonal breeder not regulated by melatonin. We have detected measurable levels of melatonin in the seminal plasma of all ejaculated semen samples (from donkey, stallion, boar, bull, and dog). Also, and for the first time, we have demonstrated the presence of MT1 and MT2 melatonin receptors in the spermatozoa of all these species, regardless their type of reproduction or sperm source (ejaculated or epididymal), using indirect immunofluorescence techniques and Western blotting. Our findings suggest that melatonin and melatonin receptors may be universally distributed in the reproductive system of mammals and that the sperm melatonin receptors cells may not be necessarily related with seasonal reproduction. Furthermore, the presence of MT1 at the cytoplasmic droplet in immature ejaculated stallion spermatozoa found in one sample and epididymal red deer spermatozoa suggests that melatonin may be involved in specific functions during spermatogenesis and sperm maturation, like protecting spermatozoa from oxidative damage, this activity being mediated through these receptors.S

Aves del departamento del Cauca - Colombia

The Cauca department with its biogeographic diversity is one of the most diverse departments in bird species of Colombia. Looking for quantify the richness reported to the date and look at their geographical distribution, we made a information compilation about bird records in the department of Cauca by reviewing publications and ornithological collections in several world museums. We obtained a list of 1,102 species, including 18 endemic spp., 96 north migratory spp. and 41 nationally endangered spp.. This check list is a suitable tool for bird study in Cauca and is a reference to understand different bird topics in southwestern Colombia