Free-ranging Populations Research Articles

Age-Related Differences in Ocular Features of a Naturalistic Free-Ranging Population of Rhesus Macaques.

Rhesus macaques (Macaca mulatta) are the premier nonhuman primate model for studying human health and disease. We investigated if age was associated with clinically relevant ocular features in a large cohort of free-ranging rhesus macaques from Cayo Santiago, Puerto Rico. We evaluated 120 rhesus macaques (73 males, 47 females) from 0 to 29 years old (mean ± SD: 12.6 ± 6.4) from September to December 2021. The ophthalmic evaluation included intraocular pressure (IOP) assessment, corneal pachymetry, biomicroscopy, A-scan biometry, automated refraction, and fundus photography after pupil dilation. The associations of age with the outcomes were investigated through multilevel mixed-effects models adjusted for sex and weight. On average, IOP, pachymetry, axial length, and automated refraction spherical equivalent were 18.37 ± 4.68 mmHg, 474.43 ± 32.21 µm, 19.49 ± 1.24 mm, and 0.30 ± 1.70 diopters (D), respectively. Age was significantly associated with pachymetry (β coefficient = -1.20; 95% confidence interval [CI], -2.27 to -0.14; P = 0.026), axial length (β coefficient = 0.03; 95% CI, 0.01 to 0.05; P = 0.002), and spherical equivalent (β coefficient = -0.12; 95% CI, -0.22 to -0.02; P = 0.015). No association was detected between age and IOP. The prevalence of cataracts in either eye was 10.83% (95% CI, 6.34-17.89) and was significantly associated with age (odds ratio [OR] = 1.20; 95% CI, 1.06-1.36; P = 0.004). Retinal drusen in either eye was observed in 15.00% (95% CI, 9.60-22.68) of animals, which was also significantly associated with age (OR = 1.14; 95% CI, 1.02-1.27; P = 0.020). Rhesus macaques exhibit age-related ocular associations similar to those observed in human aging, including decreased corneal thickness, increased axial length, myopic shift, and higher prevalence of cataract and retinal drusen.

Tongue-flicking: an idiosyncratic displacement behaviour in a free-ranging and urban-dwelling population of Balinese long-tailed macaques

Abstract This brief report describes the occurrence of an idiosyncratic behaviour, labelled tongue-flicking, that was performed by one subadult male long-tailed macaque living in a free-ranging population in Bali, Indonesia. Tongue-flicking may serve a similar purpose as a displacement behaviour in which the subject sticks his tongue out of his mouth and moves it either slightly up and down or in and out without bringing it all the way back into the mouth. Additionally, while abnormal behaviours in non-human animals are almost exclusively reported in captive individuals, the investigation of idiosyncratic behaviours such as tongue-flicking allows us to explore the potential occurrence of abnormal behaviours in free-ranging populations. This preliminary descriptive analysis of tongue-flicking aims to highlight the need for understanding the motivational bases and affective implications (e.g., welfare) of abnormal behaviours in captive and free-living animals.

Discriminating dietary behaviour between wild and domestic goats using dental microwear texture: first results from a modern reference set and early Neolithic goat exploitation in the southern Levant

Current evidence supports the idea that animal domestication occurred in multiple loci and at different time periods throughout the Near East rather than according to a single origin. In this scenario, the southern Levant is being increasingly considered as another presumed primary centre of goat domestication, alongside eastern Anatolia and the Zagros. Assessing the status (i.e. wild or domestic) of this animal in this region, however, is hampered by the difficulty of morphologically distinguishing domestic goats from their wild relatives. Diet reconstruction is a powerful approach to address this issue since the feeding of managed animals is partially controlled by their owners, unlike free-ranging wild populations. For the first time, we propose to contribute to this question through dental microwear texture analysis (DMTA) using confocal microscopy.Characterising how the dietary behaviour of extant wild and domestic goats is reflected in DMTA is critical. For this purpose, we constructed a reference collection composed of three wild goat species (19 Capra pyrenaica from the southern Iberian Peninsula, 12 Capra ibex from the Alps and 12 Capra nubiana from the Near East) and 15 domestic goats (Capra hircus) reared in an extensive system in Mediterranean scrubland areas.The preliminary results indicate that DMTA allows discrimination of the groups of extant goats. The results obtained were used to characterise the palaeodiet of 16 goats (Capra format aegagrus) from two key Early and Middle Pre-Pottery Neolithic B sites in the southern Levant: Kharaysin (Zarqa, Jordan, ca. 8800-7500 cal BC) and Qarassa (As-Suweyda, Syria, 8700-8200 cal BCE). The higher variability in archaeological goats could be an indicator of controlled feedings. It could also support the hypothesis about diverse and experimental management systems at the first steps of animal domestication.This paper shows the potential of this tool to address the process of early animal domestication. Following this initial work, the reference collection will include a broader spectrum of livestock management strategies and the archaeological corpus will be expanded through new samples during upcoming excavations and the integration of additional sites.

DETECTION OF ELEPHANT ENDOTHELIOTROPIC HERPESVIRUS (EEHV) IN FREE-RANGING AFRICAN ELEPHANTS (LOXODONTA AFRICANA) IN THE KRUGER NATIONAL PARK, SOUTH AFRICA.

Elephant endotheliotropic herpesvirus (EEHV) infection can cause acute, often fatal, EEHV hemorrhagic disease in free-ranging and human-managed Asian elephants (Elephas maximus) and human-managed African elephants (Loxodonta africana). However, significant knowledge gaps exist pertaining to the presence of EEHV in free-ranging African elephant populations. We retrospectively screened 142 opportunistically collected samples (blood, n=98; bronchoalveolar lavage (BAL) fluid, n=21; trunk wash (TW) fluid, n=23) obtained between 2010 and 2020 from 98 free-ranging African elephants in the Kruger National Park, South Africa, for the presence of different EEHVs, as well as determining the real-time quantitative PCR positivity rate in this population. With the use of validated, previously published DNA extraction and real-time quantitative PCR protocols provided by the National Elephant Herpesvirus Laboratory (Washington, DC, USA), EEHV was detected in nine male African elephants from samples collected in 2011 (n=1), 2013 (n=1), 2018 (n=2), 2019 (n=4), and 2020 (n=1). Viral detection was more common in respiratory compared with blood samples. Six elephants tested positive for EEHV2 subtype (blood, n=2; BAL, n=3; TW, n=2), including one individual that tested positive on matched respiratory samples (BAL and TW). Four elephants tested positive for EEHV3-4-7 (blood, n=1; BAL, n=2; TW, n=1), whereas EEHV6 was not detected in any of the study animals. One elephant tested positive for both EEHV2 and EEHV3-4-7 in the same BAL sample. Even though the levels of viremia varied between 158 and 1,292 viral genome equivalents/mL blood and viral shedding of EEHV2 and EEHV3-4-7 was detected in respiratory samples, no clinical signs were observed in these apparently healthy elephants. These findings are consistent with reports of asymptomatic EEHV infection in human-managed African elephants.

The introduction of African cheetahs to India was planned without considering their spatial ecology

The introduction of African cheetahs to India was planned without considering their spatial ecology

Two's company, three species is a crowd? A webcam-based study of the behavioural effects of mixed-species groupings in the wild and in the zoo.

Mixed species exhibits in zoos are used to create larger, more stimulating environments to support naturalistic interactions between species. In the wild, mixed species groups are observed as having lower rates of vigilance, presumably due to reduced predation risk through 'detection' and 'dilution' effects. This effect appears to be highly variable depending on factors such as food availability or degree of threat. This study aimed to collect data on mixed-species associations and consequent vigilance rates in the wild, collecting equivalent data from a large mixed-species zoo enclosure to compare the findings between free-ranging and captive populations. The study additionally investigated whether large mixed-species enclosures support natural associations and behaviours, by comparing the behaviour of captive animals with wild counterparts. The study used livestream video feeds from 10 national parks in South Africa and Kenya to observe free-ranging species, and a camera at the San Diego Zoo Safari Park's mixed species African exhibit. Scan and continuous sampling protocols were used simultaneously to record behavioural states as well as the rate of scanning (vigilance) events. GLMMs were run to test whether vigilance of a focal species varied according to the number of animals present, the density of animals in the group, and the diversity of species. In the wild, vigilance decreased with increasing number of animals in the surroundings but in captivity the group size had no impact. The results suggest that in the wild, these species benefit from increased perceived safety in larger groups, regardless of the species making up that group. No effect was noted in the zoo because of a reduced need for animals to show heightened vigilance to the same degree as in the wild. Similarities were observed in associations between species/mixed species group compositions, and in behaviour budgets. These findings provide a preliminary evaluation of how the impact of mixed species groupings may translate from the wild to the zoo, based on the associations and behaviour across a variety of African ungulates.

Regardless of personality, males show similar levels of plasticity in territory defense in a Neotropical poison frog

Animal personality traits are sometimes linked to an individual’s degree of plasticity, with certain personality types being more plastic than others. In territorial species, consistently high levels of aggression might increase the risk of harmful fights, while consistently low aggression might lead to the loss of a territory. Consequently, reacting plastically with an appropriate territorial response should be beneficial to avoid these risks. An integrative investigation of both personality traits and plasticity can help us better understand the dynamics of aggressive interactions during male-male competition. Here, we used a free-ranging Neotropical poison frog population to investigate the role of plasticity in male territorial aggression towards intruders. We conducted repeated standardized territorial intrusion experiments mimicking frogs of different body sizes via playback calls with different peak frequencies. We found individual repeatability for the latency to reach and approach a simulated intruder and observed that both aggressive and less aggressive males decreased their level of aggression towards big intruders. However, our results do not support a correlation between personality and plasticity in the context of male territory defense during the breeding season. We discuss how such a correlation between personality and plasticity might be conditional on the costs and benefits across contexts.

Lahaul-Zanskar-Sham Valley Corridor in Indian Trans Himalayan Region Facilitates Dispersal and Gene Flow in Himalayan Ibex.

Wildlife corridors that connect mosaic habitats in heterogeneous mountainous landscapes can be of high significance as they facilitate the genetic and demographic stability of free-ranging populations. Peripheral populations of widespread species are usually ignored in conservation planning. However, these populations retain locally common alleles and are genetic reservoir under the changing climatic conditions. Capra sibirica has widespread distribution, and its southern peripheral population is distributed in the Indian trans-Himalayan region (ITR). In the present study, we studied the spatial distribution and genetic make-up of Himalayan ibex from the ITR following the landscape genetics approach. We obtained 16 haplotypes at the mitochondrial d-loop region and found a stable demography in the past with a recent decline. With 10 nuclear microsatellites, we ascertained 111 unique individuals assigned into two clusters following Bayesian and non-Bayesian clustering analysis with several admixed individuals. We also recorded 25 first-generation migrants that reflected relatively high dispersal and gene-flow across the range. We identified a 19,835 sq.km suitable area with 13,311 sq.km in Ladakh and 6524 sq.km in Lahaul-Spiti. We identified a novel movement corridor for Himalayan ibex across the Lahaul-Zanskar-Sham valley (L-Z-SV) that displayed a fairly good conductance with low genetic divergence among the samples collected on the L-Z-SV corridor. We propose declaring a protected area in the Lahaul and Kargil districts to prioritize dedicated conservation efforts for the Himalayan ibex and other sympatric ungulates that impart a major role in the diet of large carnivore and balancing ecosystem services in the trans-Himalayan region.

Coproduction and modeling spatial contact networks prevent bias about infectious hematopoietic necrosis virus transmission for Snake River Basin salmonids

Much remains unknown about variation in pathogen transmission across the geographic range of a free-ranging fish or animal species and about the influence of movement (associated with husbandry practices or animal behavior) on pathogen transmission. Salmonid hatcheries are an ideal system in which to study these processes. Salmonid hatcheries are managed for endangered species recovery, supplementation of threatened or at-risk fish stocks, support of fisheries, and ecosystem stability. Infectious hematopoietic necrosis virus (IHNV) is a rhabdovirus of significant concern to salmon aquaculture. Landscape IHNV transmission dynamics previously had been estimated only for salmonid hatcheries in the Lower Columbia River Basin (LCRB). The objectives of this study were to estimate IHNV transmission dynamics in a unique geographic region, the Snake River Basin (SRB), and to quantitatively estimate the effect of model coproduction on inference because previous assessments of coproduction have been qualitative. In contrast to the LCRB, the SRB has hatchery complexes consisting of a main hatchery and ≥1 satellite facility. Knowledge about hatchery complexes was held by a subset of project researchers but would not have been available to project modelers without coproduction. Project modelers generated and tested multiple versions of Bayesian susceptible-exposedinfected models to realistically represent the SRB and estimate the effect of coproduction. Models estimated the frequency of transmission routes, route-specific infection probabilities, and infection probabilities for combinations of salmonid hosts and IHNV lineages. Model results indicated that in the SRB, avoiding exposure to IHNV-positive adult salmonids is the most important action to prevent juvenile infections. Migrating adult salmonids exposed juvenile cohort-sites most frequently, and the infection probability was greatest following exposure to migrating adults. Without coproduction, the frequency of exposure by migrating adults would have been overestimated by 70 cohort-sites, and the infection probability following exposure to migrating adults would have been underestimated by∼0.09. The coproduced model had less uncertainty in the infection probability if no transmission route could be identified (Bayesian credible interval (BCI) width = 0.12) compared to the model without coproduction (BCI width = 0.34). Evidence for virus lineage MD specialization on steelhead and rainbow trout (both Oncorhynchus mykiss) was apparent without model coproduction. In the SRB, we found a greater probability of virus lineage UC infection in Chinook salmon (Oncorhynchus tshawytscha) compared to in O. mykiss, whereas in the LCRB, UC more clearly exhibited a generalist approach. Coproduction influenced estimates that depended on transmission routes, which operated differently at main hatcheries and satellite sites within hatchery complexes. Hatchery complexes are found outside of the SRB and are not specific to salmonid hatcheries alone. There is great potential for coproduction and modeling spatial contact networks to advance understanding about infectious disease transmission in complex production systems and surrounding free-ranging animal populations.

Molecular identification of Sarcocystis species in sika deer (Cervus nippon) of free-ranging populations in Germany and Austria.

In this study, for the first time, Sarcocystis species were identified molecularly in sika deer (Cervus nippon) that form free-ranging populations in several countries of Europe. Diaphragm muscle samples from 151 deer from 10 populations in Germany and Austria were examined for sarcocysts. By one-gram methylene-blue staining, sarcocysts were recorded in samples of 114 animals (75.5%) which originated from all populations. Sarcocysts were more often (p < 0.0001) recorded in yearling and adult deer than in calves. Infection intensity was generally low with ~ 70% of the sarcocyst positive deer harbouring ≤ 10 sarcocysts per 1-gram diaphragm muscle. Based on cox1 sequence comparison, 10 species of Sarcocystis, all previously reported parasitizing cervids, were identified: S. elongata, S. entzerothi, S. hjorti, S. iberica, S. japonica, S. linearis, S. morae, S. pilosa, S. silva and S. truncata. The prevailing S. hjorti was detected in sika deer of all 10 populations. The identification in sika deer of S. hjorti, S. iberica, S. elongata, S. linearis, S. morae and S. silva constitutes new host records. With the additional species records of this study, the highest number of Sarcocystis species, at least 16, was identified in this host.

Dose metric evaluation of a cell-based bioassay for assessing the toxicity of metals to Dugong dugon: Effect of metal-media interactions on exposure concentrations

Cell-based toxicity testing has emerged as a useful tool in (eco)toxicological research, allowing the ethical assessment of the effects of contaminants such as trace metals on marine megafauna. However, metal interactions with various dissolved ligands in the microplate environment may influence the effective exposure concentrations. Hence, the cells are not exposed to the nominal concentrations within the test system. This study aimed to establish and evaluate the effectiveness of cell-based bioassays for investigating the toxicity of selected metals in dugongs through the following objectives: (1) measure the cytotoxic potential of cadmium (Cd2+), and chromium (Cr6+) to dugong skin cell cultures, (2) investigate the interactions between media constituents and selected trace metals in cell-based bioassays, and (3) evaluate the risk to a free-ranging population of dugong based on effect values. Chromium was the most toxic of the metals tested (EC50 = 1.14 µM), followed by Cd (EC50 = 6.35 µM). Assessment of ultrafiltered (< 3 kDa) exposure media showed that 1% and 92.5% of Cr and Cd were associated with larger organic components of the media. Further, the binding of Cd to media constituents was calculated to underestimate Cd toxicity in cell-based assays by an order of magnitude. This understanding of metal partitioning in cell-based bioassays provides a more accurate method for assessing toxicity in cell-based bioassays. In addition, this study illustrated that dugong cells are more sensitive to Cr and Cd than other marine wildlife species. The chemical risk assessment found the dugong population in Moreton Bay to be at high risk from Cd exposure.

Predation of wolves on feral horses in Apennines Areas of Southern Italy: A Case Study Report

Although wolf predation on horses is generally low, it can be significant where horses are grazed extensively and there are low densities of wild prey, such as in Southern Europe. The economic damage of wolf predation on horses can have a major impact in certain situations involving free-ranging horse populations and the topic needs more attention. This is the case of Spain, Portugal and Italy where it is possible to find many examples of wolf predations on feral horses. The main factor predisposing horses to wolf pre¬dation worldwide is the free-ranging management system. In Italy special attention is given to the horses bred in a particular area of the Southern Apennines: the Pentro horses; they represent a rare endangered equine population of Molise Region with its owns genetic characterisation. The losses of horses caused by wolves predations increase exponentially from year to year. Considering the very low number of Pentro Horses, any prey represents a considerable loss from a morphological and genetical point of view. Consequently, the predation phenomena represent a considerable limit to the selection and maintenance of these horses. This is why it was decided to create a special database with the aim of monitoring, analyzing and preventing predatory phenomena and consequently to keep under control the number of predatory events by the wolf. The database was processed by collection of data concerning: when the predation take place, the age of the preyed equines, the type of injury and the parts of the body injured or removed by the wolf, the body location of the damage and the recognition and value of money compensation. The data collected evidenced how there is a need for innovative approaches to prop¬erly mitigate predation and support the traditional free-ranging husbandry system with its high ecologi¬cal and cultural value.

Treatment with the immunocontraceptive vaccine, GonaCon, induces temporary fertility control in free-ranging prairie dog populations in Colorado, USA

Context Prairie dogs (Cynomys spp.) are rodents enjoyed by some humans; yet, they cause crop and property damage, and carry zoonotic disease. Non-lethal control of prairie dogs is of interest in urban/suburban settings. The injectable immunocontraceptive vaccine GonaCon (active ingredient is gonadotropin-releasing hormone [GnRH]) has been shown to be effective at reducing fertility in equine and deer, and is a US EPA-registered vaccine for use in these ungulate species. Aims To conduct a replicated field study to test efficacy of GonaCon in black-tailed prairie dogs (C. ludovicianus), and if found to be efficacious, to help facilitate the EPA registration of this product for prairie dog management in urban/suburban areas. Methods Prairie dogs were live-trapped in October–December 2018 in three treatment and three control sites. Every captured female ≥660 g was injected with 0.4 mL of either GonaCon (0.032% w/w GnRH) at treatment sites or a sham vaccine (absent of GnRH) at control sites. Juveniles and adults were counted at all six sites to establish juvenile:adult (ratio) and juvenile density in May–June 2019 (determining initial GonaCon effectiveness) and 2020 (determining persistence of contraception). Key results In 2019, the juvenile:adult ratio was significantly reduced (P = 0.0022) in GonaCon (mean ± s.e.: 0.23 ± 0.01) relative to the sham (1.10 ± 0.58) sites. Juvenile density was three times greater in sham than GonaCon sites. In 2020, GonaCon sites produced equal offspring to nearby sham sites. Conclusions GonaCon is highly effective during the first year (2019) but not in the second year (2020) if only a small area (0.6–2.8 ha) or small proportion of females in a colony is treated, such as was undertaken in this study. Implications In 2022, GonaCon−Prairie Dogs was EPA-registered. Treating whole colonies of prairie dogs at once is favoured; yet, if small or partial colony treatment is desired, then annual GonaCon treatment may be needed.

Estimating pregnancy rate from blubber progesterone levels of a blindly biopsied beluga population poses methodological, analytical and statistical challenges.

Beluga (Delphinapterus leucas) from the St. Lawrence Estuary, Canada, have been declining since the early 2000s, suggesting recruitment issues as a result of low fecundity, abnormal abortion rates or poor calf or juvenile survival. Pregnancy is difficult to observe in cetaceans, making the ground truthing of pregnancy estimates in wild individuals challenging. Blubber progesterone concentrations were contrasted among 62 SLE beluga with a known reproductive state (i.e. pregnant, resting, parturient and lactating females), that were found dead in 1997 to 2019. The suitability of a threshold obtained from decaying carcasses to assess reproductive state and pregnancy rate of freshly-dead or free-ranging and blindly-sampled beluga was examined using three statistical approaches and two data sets (135 freshly harvested carcasses in Nunavik, and 65 biopsy-sampled SLE beluga). Progesterone concentrations in decaying carcasses were considerably higher in known-pregnant (mean ± sd: 365 ± 244ng g-1 of tissue) than resting (3.1 ± 4.5ng g-1 of tissue) or lactating (38.4 ± 100ng g-1 of tissue) females. An approach based on statistical mixtures of distributions and a logistic regression were compared to the commonly-used, fixed threshold approach (here, 100ng g-1) for discriminating pregnant from non-pregnant females. The error rate for classifying individuals of known reproductive status was the lowest for the fixed threshold and logistic regression approaches, but the mixture approach required limited a priori knowledge for clustering individuals of unknown pregnancy status. Mismatches in assignations occurred at lipid content < 10% of sample weight. Our results emphasize the importance of reporting lipid contents and progesterone concentrations in both units (ng g-1 of tissue and ng g-1 of lipid) when sample mass is low. By highlighting ways to circumvent potential biases in field sampling associated with capturability of different segments of a population, this study also enhances the usefulness of the technique for estimating pregnancy rate of free-ranging population.

Prevalence of Platynosomum spp infection and its association with biliary lithiasis and secondary bacterial infections in free-ranging marmosets (Callithrix spp) of the Brazilian Atlantic Forest

Platynosomosis is a parasitic disease caused by a trematode of the genus Platynosomum, a bile duct and gallbladder fluke that has been described in captive neotropical primates (New World primates; NWPs) and causes high morbidity and variable mortality. Although it is a major concern for ex-situ conservation of these animals, there are only a few studies of platynosomosis in free-ranging NWPs. Therefore, the aim of this study was to characterize platynosomosis in a free-ranging population of marmosets (Callithrix spp) from the Brazilian Atlantic Forest, focusing on the epidemiological and pathological aspects of the disease. A total of 1,001 marmosets were evaluated and on the basis of clinicoepidemiological data, histopathology, histochemistry and immunohistochemistry, we concluded that Platynosomum spp infection has a prevalence of 8.9% (confidence interval: 7.3–10.8%) in free-ranging marmosets, with a higher frequency in the Metropolitan Region of Rio de Janeiro. Infection was associated with fibrosing and proliferative cholangiohepatitis associated with biliary lithiasis (3.0% of cases) and secondary bacterial infections (14.6% of cases).

Blowing the lid off! Bottle-directed, extractive foraging strategies in synurbic bonnet macaques Macaca radiata in southern India.

Nonhuman individuals and groups, living in anthropogenic landscapes, often adopt adaptive foraging strategies, mediated by their day-to-day interactions with humans and their artefacts. Exploring such novel behavioral manifestations, especially in the Anthropocene, offers us insights into behavioral innovations and their transmission in such rapidly changing ecologies. In this study, employing field experiments, we investigated an example of human-induced, extractive foraging behavior - the extraction of liquid contents from plastic bottles - in a synurbic bonnet macaque Macaca radiata population. The main aims of the study were to examine the distribution, diversity, inter-individual variability and intra-individual flexibility of bottle-directed manipulative behaviors, and to explore the social and environmental factors driving this behavioral practice. We video-recorded the manipulation of partially filled plastic bottles and the extraction of liquid across four groups of bonnet macaques in southern India. Two socio-demographic factors - age class and group membership - and one environmental factor - food provisioning - were identified as major determinants of inter-individual variation in the performance of sophisticated manipulative techniques and in bottle-opening success. Our results also suggest that age-related physical maturation, experiential trial-and-error learning, and possibly social learning contributed to the acquisition of foraging competence in this task. These findings illuminate the mechanisms underlying inter-individual behavioral variability and intra-individual behavioral flexibility amongst free-ranging individuals of a cercopithecine primate species, traditionally known for its ecological adaptability and behavioral plasticity. Finally, this study documents how the presence of humans, their artefacts and their activities facilitate the development of certain behavioral traditions in free-ranging nonhuman populations, thus providing valuable insights into how human-alloprimate relations can be restructured within the increasingly resource-competitive environments of the Anthropocene.

First Molecular Identification of Trypanosomes and Absence of Babesia sp. DNA in Faeces of Non-Human Primates in the Ecuadorian Amazon.

Trypanosomes are a group of pathogens distributed in the continents of Africa, America, Asia and Europe, and they affect all vertebrates including the neotropical primate group. Information about the trypanosome's diversity, phylogeny, ecology and pathology in non-human primates (NHPs) from the neotropical region is scarce. The objective of the study was to identify Trypanosoma and Babesia molecularly in NHPs under the phylogenetic species concept. We extracted DNA from a total of 76 faecal samples collected between 2019 and 2021, from a total of 11 non-human primate species of which 46 are from captive NHPs and 30 are free-living NHPs in the Western Amazon region of Ecuador. We did not detect DNA of Babesia sp. by polymerase chain reaction test in any of the faecal samples. However, the nested-PCR-based method revealed Trypanosoma parasites by ITS gene amplification in two faecal samples; one for the species Leontocebus lagonotus (from the captive population) and a second one for Cebus albifrons (from the free-ranging population). Maximum parsimony and likelihood methods with the Kimura2+G+I model inferred the evolutionary history of the two records, which showed an evolutionary relationship with the genus Trypanosoma. Two sequences are monophyletic with Trypanosoma. However, the number of sequences available in GenBank for their species identification is limited. The two samples present different molecular identifications and evolutionary origins in the tree topology. We are most likely referring to two different species, and two different localities of infection. We suggest that health management protocols should be implemented to prevent the transmission of blood-borne pathogens such as Trypanosoma sp. among captive populations. In addition, these protocols also protect the personnel of wildlife rehabilitation centers working in close proximity to NHPs and vice versa.

OCCURRENCE OF MANGE IN AMERICAN BLACK BEARS (URSUS AMERICANUS) IN NEW YORK STATE, USA.

Mange, a parasitic skin disease caused by various species of mites, is found in free-ranging wildlife populations and has been increasingly reported in American black bears (Ursus americanus) over the last decade in New York State (NYS), USA. Our goal was to describe the geographic, seasonal, and demographic factors associated with mange in this species in NYS. Our retrospective study used historic, opportunistic data from diagnostic necropsy records and visual sighting reports collected by the NYS Wildlife Health Program from 2009 to 2018. We used chi-square tests for independence and odds ratios to examine whether geographic location, year, season, sex, age, and reason for laboratory submission were associated with mange in bears. We used maps and seasonal analysis to investigate emerging patterns. We confirmed increased black bear mange reports in recent years. Necropsy data revealed more bears submitted to the laboratory because of mange, mainly caused by Sarcoptes scabiei; females were more likely than males to present with sarcoptic mange. We found that cases of mange in the Northern Zone were widely disseminated throughout the region, whereas cases in the Southern Zone were concentrated in two areas along the Pennsylvania border. Seasonally, mange cases showed peaks occurring in late spring to early summer and in fall. Our results were on the basis of available data; a comprehensive statewide surveillance program would be useful to better understand the apparent increase in mange and its potential impact on both the welfare of individual animals and the population of black bears in NYS. Additional research on the timing of transmission dynamics associated with females in winter dens may be helpful to wildlife managers to identify strategies to mitigate deleterious spread of the disease in black bears.

Experimental reduction of haemosporidian infection affects maternal reproductive investment, parental behaviour and offspring condition.

When hosts have a long coevolutionary history with their parasites, fitness costs of chronic infection have often been assumed to be negligible. Yet, experimental manipulation of infections sometimes reveals effects of parasites on their hosts, particularly during reproduction. Whether these effects translate into fitness costs remains unclear. Here, we present the results of an experimental study conducted in a free-ranging population of red-winged blackbirds (Agelaius phoeniceus) naturally experiencing a high prevalence of haemosporidian infections, with more than 95% of breeding adults infected with parasites from one or more haemosporidian genus. To assess effects of infection during reproduction, we manipulated adult red-winged blackbird females' parasite burden by administering an anti-haemosporidian medication before onset of egg-laying. Experimental reduction of infection resulted in significant benefits to mothers and their offspring. Medicated females laid heavier clutches, invested more in incubation and provisioning behaviour, and produced more fledglings than control females. Nestlings of medicated females had higher haematocrit, higher blood glucose, and lower reactive oxygen metabolites than nestlings of control females. Overall, our results provide evidence that, even in a species with high prevalence of infection, parasites can lead to decreased maternal investment and offspring quality, substantially reducing fitness.

Seroprevalence of African swine fever in free range pigs In Taraba State, Nigeria

A cross-sectional survey was carried out in two Local Government Areas of Taraba State between the months of March to June, 2007, to asses the serological evidence of African Swine fever (ASF) virus antibodies in free range pig population. Extensive herds of pigs were targeted for this study, and a convenient sampling technique was employed based on the availability of pigs population as well as farmer’s willingness to allow their animals to be bled. A total of 304 blood samples were collected from apparently healthy pigs. Sera were tested using Blocking Enzyme linked Immuno Assay (B-ELISA).There was an overall seroprevalence of 48.7% (95% CI: 43.09- 54.3). Seroprevalence based on different locations showed a significantly (p&lt;0.05) higher prevalence of ASF 61% (95% CI: 54.9-66.9) in Wukari LGA than 26% (95% CI: 15.3-39.4) in Karin Lamido LGA. Seropositivity based on sex revealed a higher seroprevalence in females 50.4% (95 %:( CI 44.3-56.5), than in males 40% (95%: CI 27.2-54.0). This study has shown that ASF is enzootic in free-range pig population in Taraba State which entails a potential danger to pig production with its attendance negative impact on food security and means of livelihood. We recommend an ASFV ecological study to unravel the factors responsible for continues circulation and maintenance of the virus in Nigerian pig population.