A comprehensive study of the phylogeography and population genetics of the largest wild artiodactyl in the arid and cold-temperate South American environments, the guanaco (Lama guanicoe) was conducted. Patterns of molecular genetic structure were described using 514 bp of mtDNA sequence and 14 biparentally-inherited microsatellite markers from 314 samples. These individuals originated from 17 localities throughout the current distribution across Peru, Bolivia, Argentina and Chile. This confirmed well-defined genetic differentiation and subspecies designation of populations geographically separated to the northwest (L. g. cacsilensis) and southeast (L. g. guanicoe) of the central Andes plateau. However, these populations are not completely isolated, as shown by admixture prevalent throughout a limited contact zone, and a strong signal of expansion from north to south in the beginning of the Holocene. Microsatellite analyses differentiated 3 northwestern and 4-5 southeastern populations, suggesting patterns of genetic contact among these populations. Possible genetic refuges were identified, as were source-sink patterns of gene flow at historical and recent time scales. Conservation and management of guanaco should be implemented with an understanding of these local population dynamics while also considering the preservation of broader adaptive variation and evolutionary processes.
RESUMENExisten cuatro especies de camélidos sudamericanos, dos de ellos silvestres, guanaco (Lama guanicoe) y vicuña (Vicugna vicugna), y dos formas domésticas, alpaca (Lama pacos) y llama (Lama glama), cuyo origen ha sido objeto de debate. En el presente estudio la variación en el patrón de bandas G de los cromosomas de llamas y alpacas y la secuencia de dos genes mitocondriales han sido usados para estudiar el origen y la clasificación de llamas y alpacas. Patrones de bandas cromosómicas similares fueron observados en las cuatro especies de Lamini, incluso similares a los descritos para camello, Camelus bactrianus. Sin embargo, se encontraron finas y consistentes diferencias en los brazos cortos del cromosoma 1, permitiendo separar a camellos, guanacos y llamas, de las de vicuñas y alpacas. Este patrón fue consistente incluso en un híbrido guanaco x alpaca. Relaciones equivalentes fueron encontradas en las secuencias completas del gen para citocromo b, así como en el árbol de expansión mínima de las secuencias parciales de la región control, agrupando a guanacos con llamas y a vicuñas con alpacas. Los análisis filogenéticos mostraron a V. vicugna y a L. guanicoe como grupos recíprocamente monofiléticos. El análisis de las secuencias de ambos genes mostró dos clados entre las vicuñas, concordantes con las subespecies reconocidas para esta especie, pero los resultados obtenidos para guanacos no reflejaron la existencia de las cuatro subespecies previamente propuestas. El análisis combinado de variaciones cromosómicas y moleculares demostraron una alta similitud genética entre alpacas y vicuñas, así como entre llamas y guanacos. Aunque se revela hibridización direccional, nuestros resultados apoyan fuertemente la hipótesis de que la llama se deriva de L. guanicoe, y la alpaca de V. vicugna, apoyando la reclasificación de la alpaca como V. pacos.Palabras clave: Camelidae, Lama pacos, Vicugna pacos, Lama glama, cromosomas, citocromo b, d-loop. ABSTRACTFour camelid species exist in South America: two wild, the guanaco (Lama guanicoe) and the vicuña (Vicugna vicugna), and two domestic, the alpaca (Lama pacos) and the llama (Lama glama). However, the origin of the domestic species has been a matter of debate. In the present study, variations in chromosome G banding patterns and in two mitochondrial gene sequences have been used to study the origin and classification of the llama and alpaca. Similar patterns in chromosome G band structure were observed in all four Lamini species, and these in turn were similar to the bands described for camels, Camelus bactrianus. However, fine and consistent differences were found in the short arms of chromosome 1, separating camels, guanacos and llamas from vicuñas and alpacas. This pattern was consistent even in a hybrid guanaco x alpaca. Equivalent relationship
6Private Veterinary Practice, Lima, PeruThe vicuñ a (Vicugna vicugna;Miller, 1924) is a conservation success story, having recovered from near extinction in the 1960s to current population levels estimated at 275 000. However, lack of information about its demographic history and genetic diversity has limited both our understanding of its recovery and the development of science-based conservation measures. To examine the evolution and recent demographic history of the vicuñ a across its current range and to assess its genetic variation and population structure, we sequenced mitochondrial DNA from the control region (CR) for 261 individuals from 29 populations across Peru, Chile and Argentina. Our results suggest that populations currently designated as Vicugna vicugna vicugna and Vicugna vicugna mensalis comprise separate mitochondrial lineages. The current population distribution appears to be the result of a recent demographic expansion associated with the last major glacial event of the Pleistocene in the northern (18 to 221S) dry Andes 14-12 000 years ago and the establishment of an extremely arid belt known as the 'Dry Diagonal' to 291S. Within the Dry Diagonal, small populations of V. v. vicugna appear to have survived showing the genetic signature of demographic isolation, whereas to the north V. v. mensalis populations underwent a rapid demographic expansion before recent anthropogenic impacts.
Vicuñas and guanacos are two species of wild South American camelids that are key ruminants in the ecosystems where they occur. Although closely related, these species feature differing ecologies and life history characters, which are expected to influence both their genetic diversity and population differentiation at different spatial scales. Here, using mitochondrial and microsatellite genetic markers, we show that vicuña display lower genetic diversity within populations than guanaco but exhibit more structure across their Peruvian range, which may reflect a combination of natural genetic differentiation linked to geographic isolation and recent anthropogenic population declines. Coalescent-based demographic analyses indicate that both species have passed through a strong bottleneck, reducing their effective population sizes from over 20,000 to less than 1000 individuals. For vicuña, this bottleneck is inferred to have taken place ~3300 years ago, but to have occurred more recently for guanaco at ~2000 years ago. These inferred dates are considerably later than the onset of domestication (when the alpaca was domesticated from the vicuña while the llama was domesticated from the guanaco), coinciding instead with a major human population expansion following the mid-Holocene cold period. As importantly, they imply earlier declines than the well-documented Spanish conquest, where major mass mortality events were recorded for Andean human and camelid populations. We argue that underlying species' differences and recent demographic perturbations have influenced genetic diversity in modern vicuña and guanaco populations, and these processes should be carefully evaluated in the development and implementation of management strategies for these important genetic resources.
Pomegranates are known to possess anti-hypertensive, anti-atherogenic and cardioprotective effects mainly due to their pleiotropic effects on various cellular pathways, especially those triggered by oxidative stress. The aim of this study was to investigate the effect of natural standardized pomegranate (PE) extract on cardiovascular risk factors in 24 healthy volunteers who participated in a randomized, single-blind placebo-controlled study. There were 12 subjects in the PE group and 12 in the placebo group. Variables were measured at baseline and after 14 and 28 days of supplementation are anthropometry, BP, pulse wave velocity, fat and lean body mass, salivary and urinary cortisol, and cortisone, total phenolics, antioxidant capacity and lipid peroxidation. Urinary total phenolics excretion and antioxidant capacity were significantly increased after 14 and 28 days of PE intake. At day 28, there were also statistically significant decreases in systolic and diastolic blood pressure (BP), pulse wave velocity, body fat and fat mass, as well as an increase in lean body mass. Significant changes in the placebo group were not found. Glucocorticoid levels showed a significant decrease in saliva cortisol at day 28 (morning) in the PE group, and cortisol/cortisone ratio was significantly decreased following 28 days of PE intake at morning, noon, and evening. Urine free cortisol was significantly reduced at day 14. These findings suggest that pomegranate extract intake may improve antioxidant and oxidative stress status and play a beneficial role in the attenuation of some cardiovascular risk factors. Future studies should concentrate on overweight and older people.
Using polymerase chain reaction, we investigated the extent to which digestion affects the potential to amplify 12S mitochondrial DNA sequences from bloodmeals of individual human body lice (Pediculus humanus L.) (Phthiraptera, Pediculidae) up to 72 h after feeding on a surrogate rabbit host (Oryctolagus cuniculus L.) (Lagomorpha, Leporidae). Two rabbit-specific primer pairs were developed to produce amplicons of 199 bp and 283 bp, the smaller of which was found to have a significantly slower decay rate. Median detection periods (T50) for the amplicons were 20 h and 12 h, with maximum detection periods of 24 h and 12 h, respectively, suggesting an inversely proportional linear relationship between amplicon size and digestion time. The data provide an indication of timeframes essential for the design of forensic sampling protocols and a basis for investigating the feeding frequency of human lice.
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