Highly Pathogenic Avian Influenza A(H5N1) Viruses from Multispecies Outbreak, Argentina, August 2023

We report full-genome characterization of highly pathogenic avian influenza A(H5N1) clade 2.3.4.4b virus from an outbreak among sea lions (August 2023) in Argentina and possible spillover to fur seals and terns. Mammalian adaptation mutations in virus isolated from marine mammals and a human in Chile were detected in mammalian and avian hosts.

Trichinella Infection in Culled Wild Boar (Sus scrofa) from El Palmar National Park, Argentina, and Exposure Risk in Humans and Dogs Consuming Wild Boar Meat

Trichinellosis is a foodborne disease caused by ingestion of raw or undercooked meat containing Trichinella spp. larvae. Consumption of wild boar (Sus scrofa) meat represents an important source of human trichinellosis worldwide. In El Palmar National Park (EPNP), Argentina, invasive alien wild boars are controlled and meat from culled animals is released for public consumption following on-site artificial digestion (AD) testing. Meat trimmings and offal from the control program are often used as food for dogs (Canis familiaris). We evaluated infection and exposure to Trichinella spp. in wild boars from EPNP, as well as exposure to Trichinella spp. and associated risk factors in dogs and human consumers of wild boar meat. Trichinella spp. larvae were detected in muscle samples from 5/49 wild boars by AD (10.2%; 95% confidence interval [CI], 3.8%-23%), with a mean burden of 0.24 larvae per gram (lpg; range, 0.06-0.95 lpg). Anti-Trichinella antibodies were not detected in wild boar serum samples (n=42). In dogs, 12/34 were seropositive to Trichinella spp. (35.29%; 95%, CI, 20.3%-53.5%). Immunoglobulin (Ig) G antibodies were not detected in human serum samples (n=63). Our results reveal the presence, albeit at low prevalence, of Trichinella spp. in wild boars and exposure in dogs fed game offal. These findings suggest that the low prevalence and parasitic load in wild boars, together with the best practices applied by EPNP culling program personnel, contribute to keeping the risk of infection in people low. The dog results highlight that the parasite is circulating in the area, and therefore the risk of infection is not negligible. We recommend the implementation of an animal surveillance strategy in order to monitor the evolution of this zoonosis in the study area.

Highly pathogenic avian influenza A (H5N1) in marine mammals and seabirds in Peru

Highly pathogenic avian influenza (HPAI) A/H5N1 viruses (lineage 2.3.4.4b) are rapidly invading the Americas, threatening wildlife, poultry, and potentially evolving into the next global pandemic. In November 2022 HPAI arrived in Peru, triggering massive pelican and sea lion die-offs. We report genomic characterization of HPAI/H5N1 in five species of marine mammals and seabirds (dolphins, sea lions, sanderlings, pelicans and cormorants). Peruvian viruses belong to lineage 2.3.4.4b, but they are 4:4 reassortants where 4 genomic segments (PA, HA, NA and MP) position within the Eurasian lineage that initially entered North America from Eurasia, while the other 4 genomic segments (PB2, PB1, NP and NS) position within the American lineage (clade C) that circulated in North America. These viruses are rapidly accruing mutations, including mutations of concern, that warrant further examination and highlight an urgent need for active local surveillance to manage outbreaks and limit spillover into other species, including humans.

Exploring the relationship between environmental drivers and the manifestation of fibropapillomatosis in green turtles (Chelonia mydas) in eastern Brazil

Fibropapillomatosis (FP) is a disease characterized by epithelial tumors that can impede life-sustaining activities of sea turtles, especially green turtles (Chelonia mydas). FP is caused by a herpesvirus, but environmental factors are also thought to play a role in triggering FP tumor growth. In this study, we evaluate the epidemiology of FP tumors in green turtles along the coast of Espírito Santo, Brazil, a region where juvenile green turtles are known to aggregate with high FP prevalence. A dataset comprising 2024 beach-cast green turtles recorded through daily beach surveys on 400 km of coastline from 2018 to 2021 (inclusive) was evaluated. FP tumors were recorded in 40.9% of the individuals in this dataset, and presence of FP tumors was predicted by individual variables (presence of marine leeches, stranding code, curved carapace length, body mass-size residual) and characteristics of the stranding site (distance to nearest metallurgical plant, mean sea surface salinity (SSS), annual range of sea surface temperature (SST)). Additionally, a second dataset comprising detailed information about the size and anatomical distribution of tumors in 271 green turtles with FP from the same region was evaluated. Hierarchical clustering analysis revealed these turtles could be classified in three groups according to the anatomical distribution of their tumors, and in turn the group to which each turtle was assigned could be predicted by the study period (2010-2014 vs. 2018-2022) and by characteristics of the stranding/capture site (green turtle stranding density, mean sea surface chlorophyll-a concentration, mean SSS, mean SST, annual range of SST). These results corroborate that individual and environmental factors play a significant role driving FP epidemiology. Furthermore, the results suggest that rather than behaving as a single entity, FP may be seen as a mosaic of distinct anatomical patterns that are not necessarily driven by the same environmental factors.

Phylogeographical analysis and phylogenetic inference based on the cytochrome b gene in the genus Caiman (Crocodylia: Alligatoridae) in Central and South America

The genus Caiman is one of the most taxonomically conflicted among crocodilians. Caiman crocodilus has four subspecies: Caiman crocodilus crocodilus, Caiman crocodilus fuscus, Caiman crocodilus chiapasius and Caiman crocodilus apaporiensis, but some studies recognize Caiman yacare as a subspecies of C. crocodilus or as a C. crocodilus–C. yacare complex. In Argentina, Caiman latirostris and C. yacare are present and included in sustainable use programmes, although they have hardly been studied at the genetic level. The present study had two main objectives: (1) to study the genetic diversity, structure and phylogeny of C. yacare and C. latirostris in Argentina; and (2) to perform a phylogenetic analysis of the genus Caiman throughout its entire distribution. The results show high haplotype diversity for both species but low nucleotide diversity for C. latirostris. Phylogenetic analysis shows a clear separation between both species but, surprisingly, a well-differentiated clade belonging to the Chaco region was observed. The phylogenetic analysis exhibited clades made up of the sequences of each Caiman species, with some inconsistencies: in the clade of C. crocodilus, one sequence of C. yacare is included, and one clade is observed including sequences from C. c. fuscus and C. c. chiapasius. These data indicate the need to undertake interdisciplinary studies to clarify the taxonomic status of these crocodilian species.

Foetal growth, birth size and energetic cost of gestation in southern right whales

Abstract

The cost of reproduction greatly affects a species’ life history strategy. Baleen whales exhibit some of the fastest offspring growth rates in the animal kingdom. We quantified the energetic cost of gestation for southern right whales (Eubalaena australis) by combining whaling catch records of pregnant females with photogrammetry data on southern right whale mothers and calves from two breeding grounds in Argentina and Australia. The relationship between calf birth size and maternal length was determined from repeated measurements of individual females before and after giving birth. Fetal growth was determined from generalized linear models fitted to fetal length data from whaling operations between 1961 and 1967. Fetal length was converted to volume and mass, using the volume‐to‐length relationship of newborn southern right whales calves, and published tissue composition and energy content estimates. Fetal maintenance costs (heat of gestation) and the energy content of the placenta were predicted from published relationships and added to the fetal growth cost to calculate the total cost of gestation. Our findings showed that fetal growth rates and birth size increased linearly with maternal length, with calves being born at ∼35% maternal length. Fetal length increased curvilinearly through gestation, which resulted in an exponential increase in fetal volume and mass. Consequently, the cost of gestation was very low during the first (0.1% of total cost) and second trimester (4.9%), but increased rapidly during the last trimester (95.0%). The heat of gestation incurred the highest cost for pregnant females (73.8%), followed by fetal growth (21.2%) and the placental energy content (5.0%).

Key points

Baleen whales exhibit some of the fastest fetal growth rates in the animal kingdom. Despite this, the energetic cost of gestation is largely unknown, as well as the influence of maternal body size on fetal growth rates and calf birth sizes.

We combined historical whaling records and drone photogrammetry data to determine fetal growth rates and birth sizes in southern right whales (Eubalaena australis), from which we estimated the cost of gestation.

Calf birth size, and consequent fetal growth rates, increased positively with maternal body size.

The cost of gestation was negligible for southern right whale females during the first two trimesters, but increased rapidly during the last trimester.

These results show that late gestation incurs a significant cost for baleen whale females, and needs to be accounted for in bioenergetic models.

Sarcoptic mange outbreak decimates South American wild camelid populations in San Guillermo National Park, Argentina

Sarcoptic mange epidemics can devastate wildlife populations. In 2014, mange was first detected in vicuñas (Vicugna vicugna) and guanacos (Lama guanicoe) in San Guillermo National Park (SGNP), Argentina. This study describes the temporal dynamics of the outbreak, its effects on the park's wild camelid populations between 2017-2019, and investigates the potential source of the epidemic. From May 2017 to June 2018, transect surveys indicated a sharp decrease in the density of living vicuñas and guanacos by 68% and 77%, respectively. By April 2019 no vicuñas or guanacos were recorded on transect surveys, suggesting their near-extinction in the park. Clinical signs consistent with mange (e.g., intense scratching, hyperkeratosis, alopecia) were observed in 24% of living vicuñas (n = 478) and 33% of living guanacos (n = 12) during surveys, as well as in 94% of vicuña carcasses (n = 124) and 85% of guanaco carcasses (n = 20) examined. Sarcoptes scabiei was identified as the causal agent by skin scrapings, and the cutaneous lesions were characterized by histopathology (n = 15). Genetic characterization revealed that mites recovered from seven vicuñas (n = 13) and three guanacos (n = 11) shared the same genotype, which is consistent with a single source and recent origin of the epidemic. Tracing the potential source, we identified a governmental livestock incentive program which introduced llamas (Lama glama) in areas adjacent to SGNP in 2009, some of which had alopecic scaling consistent with sarcoptic mange. Though at the time of our study no llamas with mange were available for confirmatory sampling, we hypothesize that the introduction of mange-infected llamas may have triggered the outbreak in wild camelids. This unprecedented event in SGNP had devastating effects on dominating herbivores with potentially profound cascading effects at the community and ecosystem levels.

Ingestion of plastics and other debris by coastal and pelagic birds along the coast of Espírito Santo, Eastern Brazil

Although the ingestion of plastics and other anthropogenic debris by seabirds is a global problem, few studies have employed standardized protocols to quantify and classify the debris ingested by seabirds in the Southwest Atlantic. We evaluated the ingestion of marine debris (items >0.1 mm) by 126 coastal and pelagic birds (19 species) along the coast of Espírito Santo, Eastern Brazil. Debris were found in 30% of birds examined (11 species). Particles <1 mm accounted for 35% of all debris items. Most ingested debris were plastics (97%). Ingestion of >0.1 g of plastic debris was recorded in five species: Atlantic yellow-nosed albatrosses (Thalassarche chlororhynchos), Cory's shearwaters (Calonectris borealis), Manx shearwaters (Puffinus puffinus), brown boobies (Sula leucogaster), and Magellanic penguins (Spheniscus magellanicus). Our findings suggest that the ingestion of marine debris, especially plastics, is a common problem for coastal and pelagic birds in tropical Southwest Atlantic waters.

Anthropogenic debris in the digestive tract of a southern right whale (Eubalaena australis) stranded in Golfo Nuevo, Argentina

Over the past fifty years, interactions between anthropogenic debris and a wide range of marine species have increased. In cetaceans, the most frequent interactions have occurred through ingestion and/or entanglement, with results ranging from minor injuries to death in affected animals. While debris ingestion is widely documented in odontocetes, records are scarcer in mysticetes. This study describes the finding of plastic litter in the digestive tract of a southern right whale (Eubalaena australis) juvenile male, which was found dead on the shores of Golfo Nuevo, Chubut, Argentina in 2014. During the examination of intestinal contents, anthropogenic waste was found and classified as macro-debris (25 mm-1 m). Although this whale likely died of causes not related to this finding, it is the first record of anthropogenic debris ingestion for this species. This event adds information about the potential impact of human-made debris on a variety of aquatic species and ecosystems.

Implementing One Health approaches to confront emerging and re-emerging zoonotic disease threats: lessons from PREDICT

Recurring outbreaks of emerging and re-emerging zoonoses, such as Ebola virus disease, avian influenza, and Nipah virus, serve as a reminder that the health of humans, animals, and the environment are interconnected and that early response to emerging zoonotic pathogens requires a coordinated, interdisciplinary, cross-sectoral approach. As our world becomes increasingly connected, emerging diseases pose a greater threat, requiring coordination at local, regional, and global levels. One Health is a multisectoral, transdisciplinary, and collaborative approach promoted to more effectively address these complex health threats. Despite strong advocacy for One Health, challenges for practical implementation remain. Here we discuss the value of the One Health approach for addressing global health challenges. We also share strategies applied to achieve successful outcomes through the USAID Emerging Pandemic Threats Program PREDICT project, which serve as useful case studies for implementing One Health approaches. Lastly, we explore methods for promoting more formal One Health implementation to capitalize on the added value of shared knowledge and leveraged resources.

Putative parapoxvirus-associated foot disease in the endangered huemul deer (Hippocamelus bisulcus) in Bernardo O'Higgins National Park, Chile

The huemul (Hippocamelus bisulcus) is an endangered cervid endemic to southern Argentina and Chile. Here we report foot lesions in 24 huemul from Bernardo O’Higgins National Park, Chile, between 2005 and 2010. Affected deer displayed variably severe clinical signs, including lameness and soft tissue swelling of the limbs proximal to the hoof or in the interdigital space, ulceration of the swollen tissues, and some developed severe proliferative tissue changes that caused various types of abnormal wear, entrapment, and/or displacement of the hooves and/or dewclaws. Animals showed signs of intense pain and reduced mobility followed by loss of body condition and recumbency, which often preceded death. The disease affected both genders and all age categories. Morbidity and mortality reached 80% and 40%, respectively. Diagnostics were restricted to a limited number of cases from which samples were available. Histology revealed severe papillomatous epidermal hyperplasia and superficial dermatitis. Electron microscopy identified viral particles consistent with viruses in the Chordopoxvirinae subfamily. The presence of parapoxvirus DNA was confirmed by a pan-poxvirus PCR assay, showing high identity (98%) with bovine papular stomatitis virus and pseudocowpoxvirus. This is the first report of foot disease in huemul deer in Chile, putatively attributed to poxvirus. Given the high morbidity and mortality observed, this virus might pose a considerable conservation threat to huemul deer in Chilean Patagonia. Moreover, this report highlights a need for improved monitoring of huemul populations and synergistic, rapid response efforts to adequately address disease events that threaten the species.

Post-mortem findings in southern right whales Eubalaena australis at Península Valdés, Argentina, 2003-2012

Between 2003 and 2012, 605 southern right whales (SRW; Eubalaena australis) were found dead along the shores of Península Valdés (PV), Argentina. These deaths included alarmingly high annual losses between 2007 and 2012, a peak number of deaths (116) in 2012, and a significant number of deaths across years in calves-of-the-year (544 of 605 [89.9%]; average = 60.4 yr(-1)). Post-mortem examination and pathogen testing were performed on 212 whales; 208 (98.1%) were calves-of-the-year and 48.0% of these were newborns or neonates. A known or probable cause of death was established in only a small number (6.6%) of cases. These included ship strike in a juvenile and blunt trauma or lacerations (n = 5), pneumonia (n = 4), myocarditis (n = 2), meningitis (n = 1), or myocarditis and meningitis (n = 1) in calves. Ante-mortem gull parasitism was the most common gross finding. It was associated with systemic disease in a single 1-2 mo old calf. Immunohistochemical labeling for canine distemper virus, Toxoplasma gondii and Brucella spp., and PCR for cetacean morbillivirus (CeMV), influenza A, and apicomplexan protozoa were negative on formalin-fixed, paraffin-embedded lung and brain samples from a subset of whales; PCR for Brucella spp. was positive in a newborn/neonate with pneumonia. Skin samples from whales with gull parasitism were PCR negative for CeMV, poxvirus, and papillomavirus. This is the first long-term study to investigate and summarize notable post-mortem findings in the PV SRW population. Consistent, significant findings within or between years to explain the majority of deaths and those in high-mortality years remain to be identified.

Organochlorine pesticides and PCBs in Southern Right Whales (Eubalaena australis) breeding at Península Valdés, Argentina

Organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) were assessed in blubber from 35 dead Southern Right Whales (SRW - Eubalaena australis) stranded at Península Valdés, Argentina. The life cycle includes a feeding period in high productivity areas of the South West Atlantic and a reproductive period in coastal template waters of Argentina. Organochlorine pesticides showed higher concentrations (22.6±13.8 ng·g(-1)ww) than PCBs (7.5±10 ng·g(-1)ww). Among pesticides, HCHs, DDTs, endosulfans, dieldrin, chlordans, heptachlor epoxide, and trans-nonachlor were detected. p,p'-DDE and p,p'-DDT were present in 69% and 26% of samples, respectively. p,p'-DDT/p,p'-DDE ratio showed low values (<0.33) as a result of aged DDT inputs. However, the occurrence of only p,p'-DDT in some samples suggests a recent pesticide input. α-HCH/γ-HCH ratio (<DL-0.37) indicated no recent contribution of technical HCH mixture and/or current use of lindane. Dieldrin was present in 77% of the samples and endosulfan was detected in all samples with predominance of α- (75%) over β-endosulfan (19%) and scarce contribution of endosulfan sulphate (7%), suggesting a recent input of this insecticide to the environment in the SRW foraging area. A predominance of pentachlorobiphenyls was observed. In 21 samples at least one PCB indicator was found and PCB #118, highly toxic, contributed in 5% to total PCBs. Although all these organochlorine compounds are forbidden they were bioaccumulated in the blubber of SRW with a predominance of endosulfans, the more recently used pesticide. The absence of data on chemical pollutants in stranded dead whales is highlighted as a priority for research. This is the first study on levels, compositional patterns, and organochlorine sources in SRW. Moreover, more research including milk, and other tissues/organs is recommended considered that in the studied specimens, mostly calves, pollutants are likely transferred from the mother during pregnancy and nursing.

Stakeholders in One Health

The stakeholders in One Health include the ultimate beneficiaries (i.e. animals, people and the environment) and the organisations that work to protect them (i.e. research institutes, government ministries, international organisations and professional bodies). However, identifying these stakeholders who will contribute to One Health activities and develop solutions to complex health problems can be difficult, as these problems often affect all sectors of society. In addition, evolving concepts about health and its dependence on environmental resilience necessitate the inclusion of ministries, organisations and disciplines that may not have been traditionally considered to be related to health. The multilateral organisations with greatest responsibilities in the global health arena have recognised that the best way to protect health security and promote overall global well-being is to work together across disciplinary and jurisdictional boundaries. Permanent regional networks and ad hoc networks created to tackle specific issues (both of which require donor investment) are also facilitating improved disease surveillance and collaborative approaches to synchronised interventions across country borders. These networks necessarily involve the key ministries for One Health, those of health, agriculture/livestock, and natural resources/environment. Ministries play a critical role in the formulation and implementation of policies for the promotion of health and disease control. They contribute to all stages of the One Heath process, as do universities, which engage by generating knowledge and capacity through teaching, research and extension services. Similarly, non-governmental organisations have a key role in stewardship; resource mobilisation; generation of knowledge; capacity development; intervention design; and implementation. Finally, communities, including rural and indigenous peoples, particularly those that are in close proximity to natural areas, are at the heart of the One Health concept.

Severe soft tissue ossification in a southern right whale Eubalaena australis

The carcass of a stranded southern right whale Eubalaena australis, discovered on the coast of Golfo Nuevo in Península Valdés, Argentina, exhibited extensive orthotopic and heterotopic ossification, osteochondroma-like lesions, and early degenerative joint disease. Extensive soft tissue ossification led to ankylosis of the axial skeleton in a pattern that, in many respects, appeared more similar to a disabling human genetic disorder, fibrodysplasia ossificans progressiva (FOP), than to more common skeletal system diseases in cetaceans and other species. This is the first reported case of a FOP-like condition in a marine mammal and raises important questions about conserved mechanisms of orthotopic and heterotopic ossification in this clade.

Trace metal concentrations in southern right whale (Eubalaena australis) at Península Valdés, Argentina

The presence of essential (Fe, Mn, Zn, Cu, Ni and Al) and non-essential trace metals (Cd and Pb) was tested in liver (N=26) and kidney (N=42) from dead Southern Right Whale (SRW--Eubalaena australis) calves found beached in Península Valdés, Argentina. Essential metals were detected in all samples, particularly in hepatic tissue; though Ni and Al were accumulated mainly in the kidney. Cd and Pb were not detected in any samples. Sex and length of calves did not influence metal levels found, nor did the geographic location of carcasses. Our findings for essential metals were similar to those reported for mysticetes in other parts of the world. Except for a previous report on one SRW calf, this is the first data on trace metals for this species in Patagonia. This information is vital for SRW management considering increasing human pressures impacting their feeding and breeding grounds.

Evidence for a new avian paramyxovirus serotype 10 detected in rockhopper penguins from the Falkland Islands

The biological, serological, and genomic characterization of a paramyxovirus recently isolated from rockhopper penguins (Eudyptes chrysocome) suggested that this virus represented a new avian paramyxovirus (APMV) group, APMV10. This penguin virus resembled other APMVs by electron microscopy; however, its viral hemagglutination (HA) activity was not inhibited by antisera against any of the nine defined APMV serotypes. In addition, antiserum generated against this penguin virus did not inhibit the HA of representative viruses of the other APMV serotypes. Sequence data produced using random priming methods revealed a genomic structure typical of APMV. Phylogenetic evaluation of coding regions revealed that amino acid sequences of all six proteins were most closely related to APMV2 and APMV8. The calculation of evolutionary distances among proteins and distances at the nucleotide level confirmed that APMV2, APMV8, and the penguin virus all were sufficiently divergent from each other to be considered different serotypes. We propose that this isolate, named APMV10/penguin/Falkland Islands/324/2007, be the prototype virus for APMV10. Because of the known problems associated with serology, such as antiserum cross-reactivity and one-way immunogenicity, in addition to the reliance on the immune response to a single protein, the hemagglutinin-neuraminidase, as the sole base for viral classification, we suggest the need for new classification guidelines that incorporate genome sequence comparisons.

First Detection of Bacillus anthracis in Feces of Free-ranging Raptors from Central Argentina

Prevalence of anthrax spores in feces of raptors was determined from samples collected in November-December 2000 and April-May 2001 in an agricultural region of Santa Fé province, Argentina. Feces were tested from 48 birds of six raptor species. One of 14 chimango caracaras (Milvago chimango) and one of eight road-side hawks (Buteo magnirostris) tested positive. The prevalence of Bacillus anthracis spores in feces for the six species was 4% (n=48). The prevalence was 7% (n=14) for chimango caracaras, 13% for road-side hawks (n=8), and 0% for the remaining species (Burrowing owl [Speotyto cunicularia] [n=17], Swainson's hawk [Buteo swainsoni] [n=3], Aplomado falcon [Falco femoralis] [n=2], and American kestrel [Falco sparverius] [n=4]). Grouped by their feeding habits, prevalence for scavenger species was not significantly different than for predators (7% vs. 3%, P>0.999). This study provides evidence that in central Argentina scavenger and non-scavenger raptors may have a role in the epidemiology of anthrax. Long-term studies to determine the extent of this potential involvement in the epidemiology of anthrax in central Argentina are required.

Disease Survey of Free-ranging Grey Brocket Deer (Mazama gouazoubira) in the Gran Chaco, Bolivia

Samples from 17 free-ranging hunter-killed grey brocket deer (Mazama gouazoubira) in the Gran Chaco, Bolivia, were collected during June-August 1999. All 17 deer appeared to be in good condition at the time of death. Gross necropsies were performed, serum was collected for serologic evaluation of selected infectious disease agents, and feces and ectoparasites were collected for evaluation of internal and external parasites. Serologic tests were positive for antibodies against bovine respiratory syncytial virus and four Leptospira interrogans serovars, with questionable results for epizootic hemorrhagic disease virus serotypes 1 and 2. No antibodies were detected to Anaplasma marginale, Babesia bigemina, Babesia bovis, Babesia odocoilei, bluetongue virus (serotypes 2, 10, 11, 13, and 17), bovine viral diarrhea virus, Brucella abortus, foot-and-mouth disease virus, infectious bovine rhinotracheitis virus, Mycobacterium avium subsp. paratuberculosis, and parainfluenza-3 virus. Sixty-four percent (7/11) of the deer had endoparasites. Amblyomma spp. ticks were found on seven deer, flies of the family Hippoboscidae on six deer, and lice on six deer.

Health Evaluation of Pampas Deer (Ozotoceros bezoarticus celer) at Campos del Tuyú Wildlife Reserve, Argentina

Samples from 14 free-ranging pampas deer (Ozotoceros bezoarticus celer) were collected in 1995 and 1998, at Campos del Tuyú Wildlife Reserve, Buenos Aires, Argentina. Hematology, serum chemistries, minerals and metals, and fecal parasites were analyzed. In addition, fecal ova and parasites were evaluated seasonally during 1998-2000. Serology for infectious diseases included blue-tongue, brucellosis, bovine respiratory syncytial virus infection, bovine viral diarrhea/mucosal disease, infectious bovine rhinotracheitis, Johne's disease (paratuberculosis), foot and mouth disease (FMD), leptospirosis (eight serovars), epizootic hemorrhagic disease, and parainfluenza-3 (PI-3). Three (21%) pampas deer had antibodies to Leptospira spp. and six (43%) to PI-3 virus. Serologic results for all other infectious agents were negative. Domestic cattle (n = 27) included in this study for comparison had antibodies to Leptospira, infectious bovine rhinotracheitis virus, bovine viral diarrhea virus, and PI-3 virus (74-100% of tested animals) and one animal (4%) to Brucella sp. All cattle had antibodies to FMD virus attributable to vaccination. This study provides the first data on the health status of the southernmost sub-species of pampas deer.

Hematology, plasma biochemistry, and serosurvey for selected infectious agents in southern giant petrels from Patagonia, Argentina

In conjunction with reproductive and feeding ecology studies on southern giant petrels (SGP, Macronectes giganteus) blood samples were collected for baseline health evaluations. Twenty-five adult SGP from a breeding colony in Chubut, Argentina, were sampled during two consecutive breeding seasons, 1999-2000 (n = 15) and 2000-01 (n = 10). Values for hematology, plasma biochemistry, and minerals are described for 20 birds in apparent good physical condition. A serologic survey of exposure to selected infectious agents was also conducted on all 25 birds sampled. Southern giant petrels were serologically negative for evidence of exposure to infectious laryngotracheitis virus, avian encephalomyelitis virus, avian influenza virus, avian reovirus, infectious bursal disease virus, infectious bronchitis virus, paramyxovirus 1, 2, and 3 virus, Chlamydophila, and Aspergillus. Antibodies to avian adenovirus were found in 14% of SGP during the first sampling season, and 60% in the second year. Additionally, all birds were negative for antibodies to Salmonella pullorum at the first sampling date, but 90% had low titers the following breeding season. This study contributes to understanding the health status of South Atlantic seabirds and to establishment of baseline information for SGP. Long-term monitoring of pelagic predator-scavenger seabirds such as SGP should be established for the surveillance of marine ecosystem health.

Comparison between the antioxidant status of terrestrial and diving mammals

Many diving mammals are known for their ability to deal with nitrogen supersaturation and to tolerate apnea for extended periods. They are all characterized by high oxygen-carrying capacity in blood together with high oxygen storage in their muscle mass due to large myoglobin concentrations. The above properties theoretically also imply a high tissue antioxidant defenses (AD) to counteract reactive oxygen species (ROS) generation associated with the rapid transition from apnea to reoxygenation. Different enzymatic (superoxide dismutase, catalase, glutathione reductase, glutathione peroxidase, and glutathione S-transferase), and non-enzymatic (levels of glutathione) AD as well as cellular damage (thiobarbituric acid-reactive substances contents, as a measure of lipoperoxidation) were measured in blood samples obtained from anesthetized animals, and also in blood obtained from recently dead diving mammals, and compared to some terrestrial mammals (n=5 in both groups). The results confirmed that diving mammals have, in general, higher antioxidant status compared to non-diving mammals. Apparently, to avoid exposure of tissues to changing high oxygen levels, and therefore to avoid an oxidative stress condition related to antioxidant consumption and increased ROS generation, diving mammals possess constitutive high levels of antioxidants in tissues. These data are in agreement with short-term AD adaptations related to torpor and to animals that experience large daily changes in oxygen consumption. These data are similar to the long-term adaptations of animals that undergo hibernation, estivation, freezing-thawing and dehydration-rehydration processes. In summary, animals that routinely face high changes in oxygen availability and/or consumption seem to show a general strategy to prevent oxidative damage by having either appropriate high constitutive AD and/or the ability to undergo arrested states, where depressed metabolic rates minimize the oxidative challenge.

Health evaluation of free-ranging rockhopper penguins (Eudyptes chrysocomes) in Argentina

As part of annual colony counts in Santa Cruz Province, Argentina, a health survey of rockhopper penguins (Eudyptes chrysocomes) was conducted in 1994. Forty-five birds were examined during handling procedures, and blood and fecal samples were collected for laboratory analysis. All birds appeared to be in good condition. No ecto- or endoparasites were found. Hematology, plasma chemistry, and plasma mineral levels were measured and correlated with the results of bacterial and viral serology. Antibodies against Chlamydia sp., avian adenovirus, avian encephalomyelitis virus, infectious bronchitis virus, avian reovirus, and paramyxovirus-1, -2, and -3 were found. Mean plasma chemistry and mineral values differed between individuals testing positive and negative on serologic tests. There was no serologic evidence of exposure to avian influenza virus, duck viral enteritis, infectious bursal disease, infectious laryngotracheitis, Aspergillus sp., or Salmonella pullorum. Trace amounts of endrin were found in the plasma of one bird, but all other chlorinated pesticide and polychlorinated biphenyl levels were below detectable limits.

Health evaluation of free-ranging guanaco (Lama guanicoe)

Twenty free-ranging guanaco (Lama guanicoe) in Chubut Province, Argentina, were immobilized for health evaluations. All but two animals appeared to be in good condition. Hematology, serum chemistry, and vitamin and mineral levels were measured, and feces were evaluated for parasites. Serology tests included bluetongue, brucellosis, bovine respiratory syncitial virus, bovine viral diarrhea/mucosal disease, equine herpesvirus 1, infectious bovine rhinotracheitis, Johne's disease (Mycobacterium paratuberculosis), foot and mouth disease, leptospirosis (17 serovars), parainfluenza-3, and vesicular stomatitis. Blood samples from 20 domestic sheep (Ovis aries) maintained in the same reserve with the guanaco were also collected at the same time for serology tests. No guanaco had positive serologic tests. Sheep were found to have antibody titers to bovine respiratory syncytial virus, Johne's disease, leptospirosis, and parainfluenza-3. There was no apparent difference in external appearance or condition, or statistical difference in blood test values, between the animals that were positive or negative for parasite ova.