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Introducción: Se considera a la carne de guanaco y sus derivados un producto cárnico consumible (Art. 261, CAA). El objetivo fue evaluar los aspectos nutricionales en cortes de uso comercial (lomo y peceto) de la carne de guanaco (Lama guanicoe guanicoe), del departamento Escalante (Chubut, Argentina) durante los años 2022 y 2023. Materiales y métodos: Se obtuvieron las muestras de 10 ejemplares machos adultos. Se determinó humedad (AOAC 950.46), proteínas (AOAC 928.08), grasas totales (AOAC 960.39), cenizas (AOAC 920.153), carbohidratos (cálculo por diferencia) y colesterol (Wiener lab®). Resultados: La composición centesimal de lomo y peceto, expresada en g/100 g en base húmeda, y el contenido de colesterol, expresado en mg/100 g en base húmeda, para el año 2022, en animales faenados en la estancia La Paulina, fue: humedad 75,1±0,13 y 5,2±0,06; proteínas 22,2±0,23 y 22,3±0,18; grasas totales 0,69±0,01 y 0,68±0,02; cenizas 0,85±0,03 y 0,88±0,04; carbohidratos 1,14 y 0,95; y colesterol 58,9±4,52 y 64,4±4,20, respectivamente. No se observaron diferencias estadísticas entre la composición de ambos cortes (p>0,05). La composición centesimal de lomo y peceto, expresada en g/100 g en base húmeda, y el contenido de colesterol, expresado en mg/100 g en base húmeda, para el año 2023 fue: humedad 76,6±0,14 y 76,7±0,17; proteínas 20,6±0,21 y 20,5±0,25; grasas totales 0,58±0,03 y 0,53±0,03; cenizas 1,07±0,04 y 1,02±0,02; carbohidratos 1,21 y 1,19; y colesterol 43,5±3,17 y 37,8±2,10, respectivamente. Se observó un mayor contenido de grasa en el corte lomo (p<0,05), mientras que no se observaron diferencias estadísticas (p>0,05) para el resto de los nutrientes. Conclusiones: El guanaco es una especie abundante y silvestre, muy atractiva para el consumo humano por sus cualidades nutritivas. Este alimento autóctono representa una opción alimentaria regional, con un potencial posicionamiento en el mercado nacional e internacional como una carne exótica. La carne de guanaco presenta un contenido de proteínas ligeramente mayor, un porcentaje de grasas totales significativamente menor y un nivel de colesterol ligeramente inferior, respecto a otras carnes rojas de consumo habitual

Introduction: Guanaco meat and its derivatives are considered a consumable meat product (Art. 261, CAA). The objective was to evaluate the nutritional aspects of commercially used cuts (loin and round) of guanaco meat (Lama guanicoe guanicoe) from the Escalante department (Chubut, Argentina) during the years 2022 and 2023. Materials and Methods: Samples were obtained from 10 adult male specimens. Moisture (AOAC 950.46), protein (AOAC 928.08), total fat (AOAC 960.39), ash (AOAC 920.153), carbohydrates (calculated by difference), and cholesterol (Wiener lab®) were determined. Results: The proximate composition of loin and round, expressed as g/100 g on a wet weight basis, and the cholesterol content, expressed as mg/100 g on a wet weight basis, for the year 2022, in animals slaughtered at La Paulina ranch, was as follows: moisture 75.1±0.13 and 75.2±0.06; protein 22.2±0.23 and 22.3±0.18; total fat 0.69±0.01 and 0.68±0.02; ash 0.85±0.03 and 0.88±0.04; carbohydrates 1.14 and 0.95; and cholesterol 58.9±4.52 and 64.4±4.20, respectively. No statistical differences were observed between the composition of both cuts (p>0.05). The proximate composition of loin and round, expressed as g/100 g on a wet weight basis, and the cholesterol content, expressed as mg/100 g on a wet weight basis, for the year 2023 was as follows: moisture 76.6±0.14 and 76.7±0.17; protein 20.6±0.21 and 20.5±0.25; total fat 0.58±0.03 and 0.53±0.03; ash 1.07±0.04 and 1.02±0.02; carbohydrates 1.21 and 1.19; and cholesterol 43.5±3.17 and 37.8±2.10, respectively. A higher fat content was observed in the loin cut (p<0.05), while no statistically significant differences were observed (p>0.05) for the rest of the nutrients. Conclusions: The guanaco is an abundant and wild species, highly attractive for human consumption due to its nutritional qualities. This native food represents a regional dietary option, with potential positioning in the national and international markets as an exotic meat. Guanaco meat has a slightly higher protein content, significantly lower total fat percentage, and a slightly lower cholesterol level compared to other commonly consumed red meats

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OBJECTIVE: This article evaluates the prevalence of lesions in a modern osteological collection of guanacos (Lama guanicoe) and discusses the potential of paleopathological data to assess human intervention and environmental stress. MATERIALS: A modern osteological collection of guanacos (NISP = 862) from north-western Córdoba, Central Argentina. METHODS: The prevalence of pathological specimens per skeletal element and the pathological index (Bartosiewicz et al., 1997) was used. The prevalence of arthropathies, trauma and infections was quantified. Additionally, thorn lesions in the autopodium were recorded. RESULTS: 11.03 % of the specimens presented pathological changes and the mean pathological index was 0.01. Degenerative lesions were the most prevalent type (10.34 %), followed by traumatic (0.81 %) and infectious pathologies (0.12 %). Thorn lesions (2.55 %) were recorded especially in metapodials. CONCLUSIONS: Guanacos are exposed to the development of degenerative lesions, mainly in the autopodium and vertebrae. These lesions are probably common in camelids and should not be used to argue human management. Traumatic and infectious lesions are less frequent. SIGNIFICANCE: This work provides baseline information for the paleopathological study of South American camelids and contributes to the characterization of a regionally endangered species. LIMITATIONS: The nature of the faunal assemblage did not allow for direct correlations between pathologies and individual variables such as sex or age. SUGGESTIONS FOR FURTHER RESEARCH: The comparison of our results with other wild and domesticated modern populations would be valuable to expand the baseline information for paleopathological studies. The use of quantitative methods is encouraged for future comparative and diachronic studies.

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Shrublands and grasslands comprise over 30% of the land surface and are among the most exploited ecosystems for livestock production. Across natural landscapes, the distribution and abundance of wild herbivores are affected by interspecific competition for foraging resources, hunting and the development of infrastructure among other factors. In Argentine Patagonia, the abundance of domestic sheep grazing on native vegetation outnumbers the widely distributed guanaco (Lama guanicoe) and sheep ranching monopolizes the most productive lands. In this work, we aimed to assess the spatial variation in the abundance of guanacos in Península Valdés, a representative landscape of Patagonia, investigating the incidence of natural and human-related factors. We conducted ground surveys during the austral autumn in 2017 totaling 383.4 km along areas with and without sheep ranching. We built density surface models to account for the variation in guanaco abundance and obtained a map of guanaco density at a resolution of 4 km2. We estimated an overall density of 11.71 guanacos.km-2 for a prediction area of 3,196 km2, although the density of guanacos tripled in areas where sheep ranching was terminated (in around 20% of the surface of Península Valdés) compared to areas with sheep. Guanacos were more abundant at lower values of primary productivity and sheep stocking rates and further from inhabited ranch buildings, suggesting competition with sheep and conflict with humans. Although guanacos selected open, grass-dominated habitats across sheep-free sites, fences dividing properties and paddocks played a significant role in the spatial structure of their population in Península Valdés affecting negatively the abundance of guanacos. Our results indicate that actions to improve habitat connectivity for guanacos, favor the coexistence among guanacos and sheep ranching, and promote responsible human activities and attitudes towards wildlife are needed.

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Research on the use of unmanned aircraft systems (UAS) in wildlife has made remarkable progress recently. Few studies to date have experimentally evaluated the effect of UAS on animals and have usually focused primarily on aquatic fauna. In terrestrial open arid ecosystems, with relatively good visibility to detect animals but little environmental noise, there should be a trade-off between flying the UAS at high height above ground level (AGL) to limit the disturbance of animals and flying low enough to maintain count precision. In addition, body size or social aggregation of species can also affect the ability to detect animals from the air and their response to the UAS approach. To address this gap, we used a gregarious ungulate, the guanaco (Lama guanicoe), as a study model. Based on three types of experimental flights, we demonstrated that (i) the likelihood of miscounting guanacos in images increases with UAS height, but only for offspring and (ii) higher height AGL and lower UAS speed reduce disturbance, except for large groups, which always reacted. Our results call into question mostly indirect and observational previous evidence that terrestrial mammals are more tolerant to UAS than other species and highlight the need for experimental and species-specific studies before using UAS methods.

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Lamanema chavezi (Family Molineidae) is a parasitic nematode of South American camelids (SACs). A few studies have reported this parasite in SACs, mainly in domestic camelid species (llama and alpaca). Parasite identification by means of copro-parasitological methods is non-invasive and allows performing epidemiological studies. However, egg misidentification and difficulty to culture third-stage larvae do not allow identifying nematodes to species level. In contrast, molecular tools allow identifying eggs of gastrointestinal nematodes more accurately. However, the little genomic information available in databases for some species prevents an accurate diagnosis. In the present work, L. chavezi females present in feces of llamas from northwestern Argentina were molecularly characterized to obtain genomic information and improve parasitological diagnosis of L. chavezi-like eggs present in guanaco feces from southeastern Argentina. An 833-bp fragment of nuclear ribosomal DNA (rDNA) and a 434-bp fragment of the mitochondrial cytochrome c oxidase subunit 1 (cox1) gene from both L. chavezi females and eggs were amplified and sequenced. Comparison between sequences from females and eggs showed 99-99.6% identity to rDNA and 99.5-96.1% to the cox1 gene fragments, confirming egg morphological assignment. A higher divergence between sequences was observed in the cox1 fragment, with a maximum variation of 3.9%. The examination of eggs found in guanaco feces from southeastern Argentina and their specific molecular identification represent the first record for this host in Argentine Patagonia and contribute to improving the diagnosis of gastrointestinal nematodes in SACs, mainly in wild camelids.

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Camelids (llamas, alpacas, vicuñas, guanacos) are important for the economy of South America and Eimeria infections are important as cause of mortality in camelids. Of the five most prevalent species of Eimeria in South American camelids, Eimeria macusaniensis, Eimeria lamae, Eimeria alpacae, Eimeria punoensis, and Eimeria ivitaensis, E. macusaniensis is considered the most pathogenic. There is considerable confusion concerning the endogenous developmental stages of Eimeria spp. in camelids. Many papers on camelid coccidiosis were published in local Peruvian journals, not easily accessible to wider audience. The objective of the present paper is to summarize information on history, validity of Eimeria species, life cycle, pathogenicity, prevalence, epidemiology, diagnosis, and control of coccidiosis in camelids.

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Connectivity between populations plays a key role in the long-term persistence of species in fragmented habitats. This is of particular concern for biodiversity preservation in drylands, since water limited landscapes are typically characterized by little suitable habitat cover, high habitat fragmentation, harsh matrices, and are being rapidly degraded at a global scale. In this study, we modelled landscape connectivity between 11 guanaco Lama guanicoe populations in Chile's arid Norte Chico, a region that supports the last remnant coastal populations of this emblematic herbivore indigenous to South America. We produced a habitat suitability model to derive a regional surface resistance map, and used circuit theory to map functional connectivity, investigate the relative isolation between populations, and identify those that contribute most to the patch connectivity network. Predicted suitable habitat for L. guanicoe represented about 25% of the study region (i.e., 29,173 km2) and was heterogeneously distributed along a continuous stretch along the Andes, and discontinuous patches along the coast. As a result, we found that high connectivity current flows in the mid and high Andes formed a wide, continuous connectivity corridor, enabling connectivity between all high Andean populations. Coastal populations, in contrast, were more isolated. These groups demonstrate no inter-population connectivity between themselves, only with higher altitude populations, and for two of them, animal movement was linked to the effectiveness of wildlife crossings along the Pan-American highway. Our results indicate that functional connectivity is an issue of concern for L. guanicoe in Chile's Norte Chico, implying that future conservation and management plans should emphasize strategies aimed at conserving functional connectivity between coastal and Andean populations, as well as the protection of habitat patches likely to act as stepping stones within the connectivity network.

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Social life involves costs and benefits mostly associated with how individuals interact with each other. The formation of hierarchies inside social groups has evolved as a common strategy to avoid high costs stemming from social interactions. Hierarchical relationships seem to be associated with different features such as body size, body condition and/or age, which determine dominance ability ('prior attributes' hypothesis). In contrast, the 'social dynamic' hypothesis suggests that an initial social context is a determinant in the formation of the hierarchy, more so than specific individual attributes. Hierarchical rank places individuals in higher positions, which presumably increases resource accessibility to their benefit, including opportunities for reproduction. We evaluate the maintenance of hierarchy in a family group of guanacos (Lama guanicoe) and evaluate the possible mechanisms involved in the stability of these interactions and their consequences. We estimate the linearity of social hierarchy and their dynamics. We find evidence of the formation of a highly linear hierarchy among females with males positioned at the bottom of the hierarchy. This hierarchy is not affected by physical characteristics or age, suggesting that it is established only through intra-group interactions. Rank is not related with calves' weight gain either; however, subordinated females, with lower rank, exhibit higher rates of allosuckling. We found no evidence of hierarchical structure in calves suggesting that hierarchical relationship in guanacos could be established during the formation of the family group. Hence, our results suggest that hierarchical dynamics could be related more to social dynamics than to prior attributes. We finally discuss the importance of hierarchies established by dominance and their role in minimizing social costs of interactions.

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