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BACKGROUND: In the speciation continuum, the strength of reproductive isolation varies, and species boundaries are blurred by gene flow. Interbreeding among giraffe (Giraffa spp.) in captivity is known, and anecdotal reports of natural hybrids exist. In Kenya, Nubian (G. camelopardalis camelopardalis), reticulated (G. reticulata), and Masai giraffe sensu stricto (G. tippelskirchi tippelskirchi) are parapatric, and thus, the country might be a melting pot for these taxa. We analyzed 128 genomes of wild giraffe, 113 newly sequenced, representing these three taxa. RESULTS: We found varying levels of Nubian ancestry in 13 reticulated giraffe sampled across the Laikipia Plateau most likely reflecting historical gene flow between these two lineages. Although comparatively weaker signs of ancestral gene flow and potential mitochondrial introgression from reticulated into Masai giraffe were also detected, estimated admixture levels between these two lineages are minimal. Importantly, contemporary gene flow between East African giraffe lineages was not statistically significant. Effective population sizes have declined since the Late Pleistocene, more severely for Nubian and reticulated giraffe. CONCLUSIONS: Despite historically hybridizing, these three giraffe lineages have maintained their overall genomic integrity suggesting effective reproductive isolation, consistent with the previous classification of giraffe into four species.
Assuntos
Girafas , Animais , Girafas/genética , Quênia , Genômica , Genoma , Hibridização GenéticaRESUMO
In brief: To save endangered rhinoceros species, assisted reproductive technologies are warranted. We here report in vitro blastocyst generation of the Near-Threatened Southern white rhinoceros and, for the first time, also of the technically Extinct Northern white rhinoceros. Abstract: The Anthropocene is marked by a dramatic biodiversity decline, particularly affecting the family Rhinocerotidae. Three of five extant species are listed as Critically Endangered (Sumatran, Javan, black rhinoceros), one as Vulnerable (Indian rhinoceros), and only one white rhino (WR) subspecies, the Southern white rhinoceros (SWR), after more than a century of successful protection is currently classified as Near Threatened by the IUCN, while numbers again are declining. Conversely, in 2008, the SWR's northern counterpart and second WR subspecies, the Northern white rhinoceros (NWR), was declared extinct in the wild. Safeguarding these vanishing keystone species urgently requires new reproductive strategies. We here assess one such strategy, the novel in vitro fertilization program in SWR and - for the first-time NWR - regarding health effects, donor-related, and procedural factors. Over the past 8 years, we performed 65 procedures in 22 white rhinoceros females (20 SWR and 2 NWR) comprising hormonal ovarian stimulation, ovum pick-up (OPU), in vitro oocyte maturation, fertilization, embryo culture, and blastocyst cryopreservation, at an efficiency of 1.0 ± 1.3 blastocysts per OPU, generating 22 NWR, 19 SWR and 10 SWR/NWR hybrid blastocysts for the future generation of live offspring.
Assuntos
Fertilização in vitro , Técnicas de Reprodução Assistida , Animais , Feminino , Fertilização in vitro/veterinária , Indução da Ovulação , Blastocisto , PerissodáctilosRESUMO
African buffalo (Syncerus caffer) have been distinct from the Auroch lineage leading to domestic cattle for 5 million years, and are reservoirs of multiple pathogens, that affect introduced domestic cattle. To date, there has been no analysis of the class I MHC locus in African buffalo. We present the first data on African buffalo class I MHC, which demonstrates that gene and predicted protein coding sequences are approximately 86-87% similar to that of African domestic cattle in the peptide binding region. The study also shows concordance in the distribution of codons with elevated posterior probabilities of positive selection in the buffalo class I MHC and known antigen binding sites in cattle. Overall, the diversity in buffalo class I sequences appears greater than that in cattle, perhaps related to a more complex pathogen challenge environment in Africa. However, application of NetMHCpan suggested broad clustering of peptide binding specificities between buffalo and cattle. Furthermore, in the case of at least 20 alleles, critical peptide-binding residues appear to be conserved with those of cattle, including at secondary anchor residues. Alleles with six different length transmembrane regions were detected. This preliminary analysis suggests that like cattle, but unlike most other mammals, African buffalo appears to exhibit configuration (haplotype) variation in which the loci are expressed in distinct combinations.
Assuntos
Theileria parva , Theileriose , Animais , Bovinos/genética , Theileria parva/genética , Haplótipos , Búfalos/genética , Variação Genética , Peptídeos/genéticaRESUMO
Achieving ethically responsible decisions is crucial for the success of biodiversity conservation projects. We adapted the ethical matrix, decision tree, and Bateson's cube to assist in the ethical analysis of complex conservation scenarios by structuring these tools so that they can implement the different value dimensions (environmental, social, and animal welfare) involved in conservation ethics. We then applied them to a case study relative to the decision-making process regarding whether or not to continue collecting biomaterial on the oldest of the two remaining northern white rhinoceroses (Ceratotherium simum cottoni), a functionally extinct subspecies of the white rhinoceros. We used the ethical matrix to gather ethical pros and cons and as a starting point for a participatory approach to ethical decision-making. We used decision trees to compare the different options at stake on the basis of a set of ethical desiderata. We used Bateson's cube to establish a threshold of ethical acceptability and model the results of a simple survey. The application of these tools proved to be pivotal in structuring the decision-making process and in helping reach a shared, reasoned, and transparent decision on the best option from an ethical point of view among those available.
Que se logren decisiones éticamente responsables es crucial para el éxito de los proyectos de conservación de la biodiversidad. Adaptamos la matriz ética, el árbol de decisión y el cubo de Bateson para apoyar con el análisis ético de escenarios de conservación compleja mediante la estructuración de estas herramientas de tal manera que puedan ejecutar las diferentes dimensiones de valor (ambiental, social y bienestar animal) involucradas en la ética de la conservación. Después aplicamos las herramientas a un estudio de caso relacionado con el proceso de toma de decisiones respecto a si se debe seguir o no recolectando material biológico del rinoceronte blanco del norte (Ceratotherium simum cottoni) más viejo (una subespecie funcionalmente extinta) de los dos que existen. Usamos la matriz ética como un punto de partida para una estrategia participativa para la toma ética de decisiones y para recopilar los pros y contras éticos. Usamos el árbol de decisión para comparar las diferentes opciones en juego con base en un conjunto de deseos éticos. Usamos el cubo de Bateson para establecer un umbral de aceptación ética y modelar los resultados de una encuesta simple. La aplicación de estas herramientas demostró ser central en la estructuración del proceso de toma de decisiones y en el apoyo para lograr una decisión compartida, razonada y transparente sobre la mejor opción a partir de un punto de vista ético entre aquellos disponibles.
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Biodiversidade , Conservação dos Recursos Naturais , Animais , Perissodáctilos , Análise ÉticaRESUMO
Etorphine-azaperone immobilisation was evaluated for translocation of Masai giraffes. Nine giraffes were darted with 0.012 ± 0.001 mg/kg etorphine and 0.07 ± 0.01 mg/kg azaperone. Once ataxic, giraffes were roped for recumbency and restrained manually. Naltrexone (3 mg/mg etorphine) was immediately given intravenously to reverse etorphine-related side effects. Protocol evaluation included physiological monitoring, blood-gas analyses, anaesthetic times, and quality scores (1 = excellent, 4 = poor). Sedation onset and recumbency were achieved in 2.6 ± 0.8 and 5.6 ± 1.4 min. Cardio-respiratory function (HR = 70 ± 16, RR = 32 ± 8, MAP = 132 ± 16) and temperature (37.8 ± 0.5) were stable. Arterial gas analysis showed hypoxaemia in some individuals (PaO2 = 67 ± 8 mmHg) and metabolic acidosis (pH = 7.23 ± 0.05, PaCO2 = 34 ± 4 mmHg, HCO3- = 12.9 ± 1.2 mmol/l). Minor startle response occurred, while higher induction-induced excitement correlated to longer inductions, worse restraint, and decreased HCO3-. After 19 ± 3.5 min of restraint, giraffes were allowed to stand and were loaded onto a chariot. Immobilisations were good and scored 2 (1-3). Inductions and recoveries were smooth and scored 1 (1-2). Translocations were uneventful and no complications occurred in 14-days boma follow-up.
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Very little is known about the influence of massive and long distance migration on parasite epidemiology. Migration can simultaneously minimize exposure to common parasites in their habitats and increase exposure to novel pathogens from new environments and habitats encountered during migration, while physiological stress during long distance movement can lead to immune suppression, which makes migrants vulnerable to parasites. In this paper, we investigated the diversity, prevalence, parasite load, co-infection patterns and predilection sites of adult gastrointestinal helminths in 130 migrating wildebeests and tested for their relation with animal age, sex and migration time (which also could indicate different migration routes), and compared them with the non-migratory wildebeest. Surprisingly, only four parasite species were found, Oesophagostomum columbianum, Haemonchus placei, Calicophoron raja and Moniezia expansa, which were lower than in non-migratory wildebeest reported in the literature. These parasites were generalists, infecting livestock, and suggests that wildebeest and livestock, because of their interaction during migration, have a cross-infection risk. There was a negative relation between parasites diversity, prevalence and intensity of infection, and host age, which suggests that wildebeests acquire protective immunity against these parasites as they get older. Prevalence and intensity of infection were higher among wildebeest crossing the Mara Bridge (early migrants) compared to those crossing the Serena (late migrants), which suggests that early migrants (or migrants originating from different areas) have varying infection intensities. The prevalence and intensity of infection were higher in males compared to females and may be due to ecological, behavioural, or physiological differences between males and females. Our findings compared to those of previous studies suggest that migration may provide a mechanism to minimize exposure of hosts to common parasites through migratory escape, but this result awaits examination of helminths epidemiology of non-migratory wildebeests from areas of migrant origins. The potential parasitic cross-infection between wildebeests and livestock is a real risk to be taken into account in the management of wildebeest migration corridors.
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Migração Animal , Ruminantes/parasitologia , Animais , Ecossistema , Feminino , Helmintos , Masculino , ParasitosRESUMO
The use of biopsy darts for remote collection of tissue samples from free-ranging terrestrial and aquatic animal species has gained popularity in the recent past. The success of darting is very important since scientists may not have many chances to re-dart the same animal, especially with the free-ranging elusive wildlife species. We used wildebeest (Connochaetes taurinus) as a model to estimate the optimum shooting distance, pressure and the shot part of the body through which a researcher can optimize the success and amount of tissue collected from similar wild land mammalian species. Wildebeests were darted at six categories of distances ranging between 10 and 45 m and dart gun pressures of 5-14 millibar. The number of failed darts increased by increasing the darting distance: 0% (10 m), 0% (20 m), 6% (30 m), 20% (35 m), 71% (40 m), and 67% (45 m). There was a notable effect of the distances on the amount of tissue collected 20 m offered the best results. Dart gun pressure had no effect on the amount of tissue samples obtained. The amount of tissue obtained from successful darts was the same whether the animal was darted on the shoulder or thigh. In this paper, we present a practical guideline for remote biopsy darting of wildebeest to obtain optimum amount of tissue samples, which could be generalized for similar wild land mammalian species.
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Wildebeest-associated malignant catarrhal fever (WA-MCF), an acute lymphoproliferative disease of cattle caused by alcelaphine herpesvirus 1 (AlHV-1), remains a significant constraint to cattle production in nomadic pastoralist systems in eastern and southern Africa. The transmission of WA-MCF is dependent on the presence of the wildlife reservoir, i.e. wildebeest, belonging to the species Connochaetes taurinus and Connochaetes gnou; hence, the distribution of WA-MCF is largely restricted to Kenya, Tanzania and the Republic of South Africa, where wildebeest are present. WA-MCF is analogous to sheep-associated MCF (SA-MCF) in many aspects, with the latter having sheep as its reservoir host and a more global distribution, mainly in developed countries with intensive livestock production systems. However, unlike SA-MCF, the geographic seclusion of WA-MCF may have contributed to an apparent neglect in research efforts aimed at increased biological understanding and control of the disease. This review aims to highlight the importance of WA-MCF and the need for intensified research towards measures for its integrated control. We discuss current knowledge on transmission and geographical distribution in eastern and southern Africa and the burden of WA-MCF in affected vulnerable pastoral communities in Africa. Recent findings towards vaccine development and pertinent knowledge gaps for future research efforts on WA-MCF are also considered. Finally, integrated control of WA-MCF based on a logical three-pronged framework is proposed, contextualizing vaccine development, next-generation diagnostics, and diversity studies targeted to the viral pathogen and cattle hosts.
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Controle de Doenças Transmissíveis/tendências , Gammaherpesvirinae/fisiologia , Febre Catarral Maligna/prevenção & controle , África , Animais , Antílopes/virologia , Bovinos , Controle de Doenças Transmissíveis/métodos , Febre Catarral Maligna/virologiaRESUMO
A 10-year-old male African elephant (Loxodonta africana) at Samburu National Reserve in Northern Kenya, weighing approximately 1,600 kg, presented with an umbilical hernia in October 2013. Umbilical herniorrhaphy was carried out under field conditions. Anesthesia was induced and maintained using etorphine hydrochloride for 3 hours during the surgery. This case report details both the surgical and anesthetic procedure carried out to correct the hernia, and the eventual successful recovery of the elephant from anesthesia. However, the elephant died weeks after the surgery and a postmortem could not reveal the cause of death because predators had scavenged the carcass. The challenges of the surgical procedure and outcome including possible causes of death are highlighted in this report.
RESUMO
The discipline of epidemiology is the study of the patterns, causes and effects of health and disease conditions in defined anima populations. It is the key to evidence-based medicine, which is one of the cornerstones of public health. One of the important facets of epidemiology is disease-navigating webs (disease-NW) through which zoonotic and multi-host parasites in general move from one host to another. Epidemiology in this context includes (i) classical epidemiological approaches based on the statistical analysis of disease prevalence and distribution and, more recently, (ii) genetic approaches with approximations of disease-agent population genetics. Both approaches, classical epidemiology and population genetics, are useful for studying disease-NW. However, both have strengths and weaknesses when applied separately, which, unfortunately, is too often current practice. In this paper, we use Sarcoptes scabiei mite epidemiology as a case study to show how important an integrated approach can be in understanding disease-NW and subsequent disease control.
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Sarcoptes scabiei , Escabiose/epidemiologia , Navegador , Animais , Humanos , Sarcoptes scabiei/classificação , Sarcoptes scabiei/genética , Escabiose/parasitologia , Escabiose/prevenção & controleRESUMO
BACKGROUND: Very few studies have ever focused on the elephants that are wounded or killed as local communities attempt to scare these animals away from their settlements and farms, or on the cases in which local people take revenge after elephants have killed or injured humans. On the other hand, local communities live in close proximity to elephants and hence can play a positive role in elephant conservation by informing the authorities of the presence of injured elephants. METHODOLOGY/PRINCIPAL FINDINGS: Between 2007 and 2011, 129 elephants were monitored in Masai Mara (Kenya), of which 54 had various types of active (intentionally caused) or passive (non-intentionally caused) injuries. Also studied were 75 random control samples of apparently unaffected animals. The observed active injuries were as expected biased by age, with adults suffering more harm; on the other hand, no such bias was observed in the case of passive injuries. Bias was also observed in elephant sex since more males than females were passively and actively injured. Cases of passive and active injuries in elephants were negatively related to the proximity to roads and farms; the distribution of injured elephants was not affected by the presence of either human settlements or water sources. Overall more elephants were actively injured during the dry season than the wet season as expected. Local communities play a positive role by informing KWS authorities of the presence of injured elephants and reported 43% of all cases of injured elephants. CONCLUSIONS: Our results suggest that the negative effect of local communities on elephants could be predicted by elephant proximity to farms and roads. In addition, local communities may be able to play a more positive role in elephant conservation given that they are key informants in the early detection of injured elephants.
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Conservação dos Recursos Naturais , Elefantes , Análise Espaço-Temporal , Animais , Comportamento Animal , Elefantes/lesões , Feminino , Geografia , Quênia , Masculino , Densidade Demográfica , Fatores de Risco , Estações do AnoRESUMO
BACKGROUND: Pastoralists in low-income countries usually live in close proximity to their animals and thus represent an important repository of information about livestock disease. Since wild and domestic animals often mix freely whilst grazing, pastoralists are also able to observe first-hand the diseases that are present in wildlife and as such are key informants in disease outbreaks in sylvatic animals. We report here the findings of the first study of the knowledge and role of Masai pastoralists in mange in wildlife and livestock in Masai Mara, Kenya. METHODOLOGY/PRINCIPAL FINDINGS: In this paper we describe the knowledge of mange accrued by 56 Masai pastoralists in Kenya and how they respond to it in both wildlife and livestock. In total, 52 (93%) pastoralists had a clear idea of the clinical appearance of mange, 13 (23%) understood its aetiology and 37 (66%) knew that mites were the causal agent. Thirty-nine (69%) believed that mange cross-infection between domestic and wild animals occurs, while 48 (85%) had observed mange in domestic animals including sheep (77%), goats (57%), dogs (24%) and cattle (14%). The pastoralists had also observed wild animals infected with mange, above all lions (19%), gazelles (14%), cheetahs (12%) and wildebeests (2%). In 68% of cases Masai pastoralists treat mange infection or apply control measures, most commonly via the topical use of acaricides (29%) and/or the reporting of the outbreak to the veterinary authorities (21%). In the period 2007-2011, Kenya Wildlife Service received 24 warnings of 59 wild animals with mange-like lesions from the Masai Mara pastoralist community. The reported species were cheetah, lion, wild dog, Thomson's gazelle and wildebeest. CONCLUSION: Masai pastoralists have good knowledge of mange epidemiology and treatment. Their observations and the treatments they apply are valuable in the control of this disease in both wild and domestic animals.