Nutrition as an etiological factor causing diseases in endangered huemul deer

Distinct diseases prevent endangered huemul deer (Hippocamelus bisulcus) recovery. Fundamental etiological factors include nutriments, a mayor component of habitat quality. Undernutrition affects growth, skeletal development, osteopathology, reproduction and immunocompetence: this paper amplifies data corroborating micro-nutrient deficiencies among huemul.; In Argentina, 57% huemul cadavers exhibited osteopathology, with new cases reported here. Recently, 86% live huemul had osteopathology: cranial lesions involved antemortem tooth loss, reducing feeding efficiency and body condition, with starvation deaths. This population had tissues well deficient compared to other cervids, averaging 0.28 ppm selenium, 4.98 ppm copper, whereas for manganese 55% were deficient (2.52 ppm) and 45% adequate (42.79 ppm). Recently, lesions in one Chilean huemul were interpreted to stem from parapoxvirus. That population also has cases with cranial osteopathologies, high disease susceptibility (parapoxvirus, parasitism, foot lesions), crippled antlers, and low density, indicative of marginal habitat and primary etiological factors like undernutrition and immunosuppression. The reported atypical symptoms attributed to parapoxvirus may relate to probable diagnostic limitations, but does support presence of nutritional deficiencies. Patagonia has selenium deficient plants and livestock, including severe muscular dystrophy, and soil levels in extant huemul areas considered very deficient. Moreover, 73% of Chilean huemul were selenium deficient and 64% severely deficient with concomitant cranial osteopathology

Observations of Interactions between Puma, Puma concolor, and Introduced European Red Deer, Cervus elaphus, in Patagonia

Direct observations of interactions between native Puma (Puma concolor) and introduced European Red Deer (Cervus elaphus) in Patagonia are discussed with respect to the absence of evolutionary sympatry. Although the founding stock of European Red Deer had been lacking natural predation pressure for considerable time due to the previous extinction of large predators, these observations suggested that inherent antipredator behavior of European Red Deer toward this novel predator, once detected, was effective and may partially explain the success of European Red Deer as an invasive species. Puma behavior supported the view that they are a generalist predator which opportunistically utilizes new prey species like European Red Deer

Continuing impacts on red deer from a volcanic eruption in 2011

In June of 2011, the Puyehue-Cordon Caulle volcanic eruption deposited large amounts of ashes in Chile and Argentina. Although ashes were initially considered innoxious based on water leachates, we found clinical cases of fluoride intoxication in red deer (Cervus elaphus) and domestic herbivores in Argentina. The diagnosis was corroborated by high bone fluoride concentrations. The dynamics of temporal accumulation of fluoride suggested an average increase of 1,000 ppmper year of fluoride in the bone. However, a few deer had fluoride levels, suggesting an accumulation rate of about 3,700 ppm per year. Via recent sampling of deer, we now confirm that bone levels have reached up to 10,396 ppm of fluoride after about 28 months of exposure. Tephra across various sites averaged 548 ppm of fluoride, and due to dry conditions and eolic redeposition of ashes particularly east of the continental divide, clinical fluorosis is expected to continue to intensify. The described impact will reverberate through several aspects of the ecology of the deer, including effects on population dynamics, morbidity, predation susceptibility, as well as other components of the ecosystem, including other herbivores, scavengers, and plant communities

The impact of recent volcanic ash depositions on herbivores in Patagonia: a review

Volcanic tephra (ejected solids) result in varied impacts on ecosystems and livestock production. The recent Puyehue (2011) and Calbuco (2015) eruptions deposited large amounts of tephra in Chile and Argentina, affecting both livestock and wildlife in several ways. Impacts from Puyehue tephra on livestock were attributed initially  solely to inanition, rumen blockage, eye problems, increased mechanical tooth wear; water consumption was considered without risk for humans and animals; and toxic effects were discarded. Subsequently, wildlife exhibited pronounced clinical signs of fluorosis and bone level exceeding 10 000 ppm of fluoride by 2014. Livestock  including horses, cattle and sheep also had high levels of bone fluorine and clinical fluorosis. Tephra from Calbuco and Puyehue now overlap, containing on average 548 and 352 ppm fluoride, respectively. Dryness and eolic redeposition of tephra particularly east of the continental divide continues to re-expose domestic and wild ruminants. However, fluorosis and other related impacts like hypothyroidism, anaemia, and eosinophilia in ruminants also impact wool production. Although  fluoride was discarded by others as a cause for the observed reduction in wool production, the specific effect of fluorosis on reducing wool production is well recognised, and occurs in sheep with less bone fluoride than reported from the Puyehue event. The rapid accumulation of fluoride in herbivores exposed to tephra from Puyehue coincides with reports that upon exposure to fluoride, sheep bone levels increased from 160 to 2300 ppm in only 3 months. The susceptibility of ruminants to fluorosis resides in their food processing: (1) intensive mastication and tephra size reduction, (2) thorough mixing of tephra with alkaline saliva during repeated rumination cycles, (3) water-soluble extraction in the rumen, and (4) extraction in the acidic abomasum. Lastly, the fluorosis may be further exacerbated by regional iodine and selenium deficiencies. Iodine deficiency may increase the incidence of dental fluorosis and the severity of damage, whereas selenium deficiency causes secondary iodine deficiency.Ash depositions from the Puyehue (2011) and  Calbuco (2015) volcanic eruptions may cause havoc for wild and domestic animals and the people dependent on them. The negative impact on sheep wool production was thought to be related to reduced forage and tooth wear, but as shown here, there was also a major effect from fluoride intoxication. The recognition of toxic effects such as fluorosis have a strong bearing on diagnosing the types of impacts and selecting appropriate remedy measures aimed at reducing the impacts

Osteopathology and selenium deficiency co-occurring in a population of endangered Patagonian huemul (Hippocamelus bisulcus)

Background: About 1,000 endangered Patagonian huemul deer (Hippocamelus bisulcus) remain in Chile and 350-500 in Argentina. Most groups (>100) are not recovering, and prevalence of osteopathology in Argentina was at least 57%. Here I describe relevant cases of osteopathology from a Chilean population which, however, recently also provided data on trace mineral status, supporting the initial hypothesis that nutrition may be a primary etiologic factor. Additionally, recent data on bone chemical composition of Argentine cases and soil analyses are discussed. Results: Fluoride levels in Argentine cases with osteopathology were low and fluorosis was discarded as an etiological factor. Selenium deficiency occurred in 73% of huemul from the Chilean population which exhibited several cases with osteopathology. The pathophysiognomy included extensive erosion; tooth loss;  porosification; perforations of palate, maxillar and mandibular bone with frequent exposure of tooth roots; and fractured mandibula. Areas currently used by remaining huemul have mainly acidic volcanic soils, which reduces selenium bioavailability: mean soil selenium levels from areas typically used by extant huemul were very deficient (0.19 ppm), corroborating documented overt selenium deficiency in local livestock and plants. The area of extant huemul is known to result in primary iodine deficiency in livestock which is aggravated by selenium deficiency. Conclusions: Currently the most parsimonious explanation for frequent osteopathology and lack of numerical recovery are the combined effects of selenium and iodine deficiencies based on: osteopathology in a population of selenium deficient huemul; selenium deficient livestock, plants and soils; acidic soils; and regional primary iodine deficiency. The nexus between mineral nutrition and population dynamics of huemul may be due to constraints on their movements to fertile lowlands, including the elimination of historic migratory traditions, and concomitant elimination of source populations

Biotic Translocation of Phosphorus: The Role of Deer in Protected Areas

Biogeochemical cycles are cornerstones of biological evolution. Mature terrestrial ecosystems efficiently trap nutrients and certain ones are largely recycled internally. Preserving natural fluxes of nutrients is an important mission of protected areas, but artificially leaky systems remain common. Native red deer (Cervus elaphus) in the Swiss National Park (SNP) are known to reduce phosphorus (P) in preferred feeding sites by removing more P than is returned with feces. At larger scales it becomes apparent that losses are occurring due to seasonal deer movements out of the SNP where most deer end up perishing. Thus, the SNP contributes to producing deer which translocate P to sink areas outside the SNP due to several artificial factors. An adult female dying outside of SNP exports about 1.8 kg of P, whereas a male dying outside of SNP at 8 years of age exports 7.2 kg of P due also to annual shedding of antlers. Averaged over the vegetated part of the SNP, the about 2,000 deer export 0.32 kg/ha/yr of P. Other ungulate species using the SNP and dying principally outside of its borders would result in additional exports of P. Leakiness in this case is induced by: a) absence of the predator community and thus a lack of summer mortalities and absence of several relevant non-lethal predator effects, b) hunting-accelerated population turnover rate, and c) deaths outside of SNP principally from hunting. The estimated export rate for P compares to rates measured in extensive production systems which receive 10-50 kg/ha/yr of P as fertilizer to compensate the losses from biomass exports. Assumptions were made regarding red deer body weight or population turnover rate, yet substituting my estimates with actual values from the SNP would only affect somewhat the magnitude of the effect, but not its direction. The rate of P loss is a proxy for losses of other elements, the most critical ones being those not essential to autotrophs, but essential to heterotrophs. High deer turnover rates combined with accelerated biomass export warrants detailed mass balances of macro and micro nutrients, and studies of biogeochemical cycles in protected areas are essential if preserving natural processes is a mandate

Elusive cranial lesions severely afflicting young endangered Patagonian huemul deer

Abstract Objectives Most subpopulations of endangered huemul deer (Hippocamelus bisulcus) fail to recover, frequently due to osteopathology. Equivalent pathology was detected only postmortem in an additional deer 365 km further north, stressing the need to improve clinical evaluations of live huemul. Results Captured on a farm and attended by authorities in charge of huemul, the deer was considered apt for relocation and release. Delays with attendance and lack of reversal drugs resulted in his death. The subsequent necropsy revealed severe osteopathology particularly in mandibles and maxillae. Such disease in another southern population affected 57+ % among dead adults, and 86% among live adults. The present case stems from a new subpopulation, isolated 365 km further north. Such severe pathology demands that individuals be rehabilitated, especially relevant with severely endangered species, because liberations will cause premature death and loss of reproductive lifetime. Live huemul must be examined utmost professionally especially regarding this pathophysiognomy. This incidence represents the typical situation of extant huemul, being displaced from their traditional migratory behavior to utilize fertile low-elevation habitat. This young male may have been dispersing, but reaching valleys usually leads to death due to locally intense anthropogenic activities

Troubling disease syndrome in endangered live Patagonian huemul deer (Hippocamelus bisulcus) from the Protected Park Shoonem: unusually high prevalence of osteopathology

Abstract Objective The last 1500 endangered Patagonian huemul deer (Hippocamelus bisulcus) exist in > 100 groups which are not recovering. Prevalence of osteopathology in dead huemul was 57+% (Argentina), whereas similar cases in Chile were accompanied by selenium deficiency. The first clinical cases from live wild huemul confirm widespread osteopathology which explains short life spans, low recruitment, and thus absence of population recovery. Results The first-ever radio-collaring of 3 male huemul in Argentina and 3 females, plus a fresh female carcass allowed examination of 7 huemul. Of these, 86% were diseased and clinical pathophysiognomy included lameness, affected hoof, exfoliation of 2–7 incisors, other cranial osteopathologies, and muscle atrophy. The parsimonious explanation for absent population recovery is high prevalence of osteopathology as evidenced earlier in carcasses, and now by these clinical cases. Areas currently used by huemul have reduced selenium bioavailability, very deficient soil levels, and overt selenium deficiency in local livestock and plants. These areas are known to result in primary iodine deficiency which is aggravated by selenium deficiency. The nexus to nutritional ecology of huemul likely is inaccessibility to most fertile lowlands and traditional winter ranges, elimination of migratory traditions, and concomitant elimination of source populations