We detected bovine kobuvirus (BKV) in calves with diarrhea in the United States. The strain identified is related genetically to BKVs detected in other countries. Histopathologic findings also ...confirmed viral infection in 2 BKV cases. Our data show BKV is a potential causative agent for diarrhea in calves.
Restoring connectivity between fragmented populations is an important tool for alleviating genetic threats to endangered species. Yet recovery plans typically lack quantitative criteria for ensuring ...such population connectivity. We demonstrate how models that integrate habitat, genetic, and demographic data can be used to develop connectivity criteria for the endangered Mexican wolf (Canis lupus baileyi), which is currently being restored to the wild from a captive population descended from 7 founders. We used population viability analysis that incorporated pedigree data to evaluate the relation between connectivity and persistence for a restored Mexican wolf metapopulation of 3 populations of equal size. Decreasing dispersal rates greatly increased extinction risk for small populations (<150–200), especially as dispersal rates dropped below 0.5 genetically effective migrants per generation. We compared observed migration rates in the Northern Rocky Mountains (NRM) wolf metapopulation to 2 habitat‐based effective distance metrics, least‐cost and resistance distance. We then used effective distance between potential primary core populations in a restored Mexican wolf metapopulation to evaluate potential dispersal rates. Although potential connectivity was lower in the Mexican wolf versus the NRM wolf metapopulation, a connectivity rate of >0.5 genetically effective migrants per generation may be achievable via natural dispersal under current landscape conditions. When sufficient data are available, these methods allow planners to move beyond general aspirational connectivity goals or rules of thumb to develop objective and measurable connectivity criteria that more effectively support species recovery. The shift from simple connectivity rules of thumb to species‐specific analyses parallels the previous shift from general minimum‐viable‐population thresholds to detailed viability modeling in endangered species recovery planning. Desarrollo de Criterios de Conectividad Metapoblacional a Partir de Datos Genéticos y de Hábitat para Recuperar al Lobo Mexicano en Peligro de Extinción
We characterized novel coronaviruses detected in US bottlenose dolphins (BdCoVs) with diarrhea. These viruses are closely related to the other 2 known cetacean coronaviruses, Hong Kong BdCoV and ...beluga whale CoV. A deletion in the spike gene and insertions in the membrane gene and untranslated regions were found in US BdCoVs (unrelated to severe acute respiratory syndrome coronavirus 2).
Abstract
Defining units that can be afforded legal protection is a crucial, albeit challenging, step in conservation planning. As we illustrate with a case study of the red wolf (Canis rufus) from ...the southeastern United States, this step is especially complex when the evolutionary history of the focal taxon is uncertain. The US Endangered Species Act (ESA) allows listing of species, subspecies, or Distinct Population Segments (DPSs) of vertebrates. Red wolves were listed as an endangered species in 1973, and their status remains precarious. However, some recent genetic studies suggest that red wolves are part of a small wolf species (C. lycaon) specialized for heavily forested habitats of eastern North America, whereas other authors suggest that red wolves arose, perhaps within the last ~400 years, through hybridization between gray wolves (C. lupus) and coyotes (C. latrans). Using published genetic, morphological, behavioral, and ecological data, we evaluated whether each evolutionary hypothesis would lead to a listable unit for red wolves. Although the potential hybrid origin of red wolves, combined with abundant evidence for recent hybridization with coyotes, raises questions about status as a separate species or subspecies, we conclude that under any proposed evolutionary scenario red wolves meet both criteria to be considered a DPS: they are Discrete compared with other conspecific populations, and they are Significant to the taxon to which they belong. As population-level units can qualify for legal protection under endangered-species legislation in many countries throughout the world, this general approach could potentially be applied more broadly.
Genetic rescue and inbreeding depression in Mexican wolves Fredrickson, Richard J; Siminski, Peter; Woolf, Melissa ...
Proceedings - Royal Society. Biological sciences/Proceedings - Royal Society. Biological Sciences,
09/2007, Letnik:
274, Številka:
1623
Journal Article
Recenzirano
Odprti dostop
), inbreeding had reduced genetic diversity and potentially lowered fitness, and as a result, three unrelated captive wolf
lineages were merged beginning in 1995. We examined the effect of inbreeding ...and the merging of the founding lineages on three
fitness traits in the captive population and on litter size in the reintroduced population. We found little evidence of inbreeding
depression among captive wolves of the founding lineages, but large fitness increases, genetic rescue, for all traits examined
among, Although inbreeding can reduce individual fitness and contribute to population extinction, gene flow between inbred but unrelated
populations may overcome these effects. Among extant Mexican wolves (, Canis lupus baileyi, offspring of the founding lineages. In addition, we observed strong inbreeding depression among wolves descended from, wolves. These results suggest a high load of deleterious alleles in the McBride lineage, the largest of the founding lineages.
In the wild, reintroduced population, there were large fitness differences between McBride wolves and wolves with ancestry
from two or more lineages, again indicating a genetic rescue. The low litter and pack sizes observed in the wild population
are consistent with this genetic load, but it appears that there is still potential to establish vigorous wild populations.
A cytopathic virus was isolated using Madin-Darby bovine kidney (MDBK) cells from lung tissue of alpaca that died of a severe respiratory infection. To identify the virus, the infected cell culture ...supernatant was enriched for virus particles and a generic, PCR-based method was used to amplify potential viral sequences. Genomic sequence data of the alpaca isolate was obtained and compared with sequences of known viruses. The new alpaca virus sequence was most similar to recently designated Enterovirus species F, previously bovine enterovirus (BEVs), viruses that are globally prevalent in cattle, although they appear not to cause significant disease. Because bovine enteroviruses have not been previously reported in U.S. alpaca, we suspect that this type of infection is fairly rare, and in this case appeared not to spread beyond the original outbreak. The capsid sequence of the detected virus had greatest homology to Enterovirus F type 1 (indicating that the virus should be considered a member of serotype 1), but the virus had greater homology in 2A protease sequence to type 3, suggesting that it may have been a recombinant. Identifying pathogens that infect a new host species for the first time can be challenging. As the disease in a new host species may be quite different from that in the original or natural host, the pathogen may not be suspected based on the clinical presentation, delaying diagnosis. Although this virus replicated in MDBK cells, existing standard culture and molecular methods could not identify it. In this case, a highly sensitive generic PCR-based pathogen-detection method was used to identify this pathogen.
Leptospirosis is recognized as the most globally widespread reemerging zoonosis and represents a serious threat for both human and animal health. Indeed, leptospirosis is linked to more than 60,000 ...human deaths per year and to incalculable economic burden as consequence of medical treatment costs and livestock loss. The increasing number of reports from species of pathogenic
spp. group II causing disease in both humans and animals constitutes an additional concern to the complex epidemiology of this zoonotic agent. Diagnostic methods based on qPCR have improved the diagnosis of
spp. in terms of cost, time, and reliability, but most of the validated assays fail to detect species from the pathogenic group II. Hence, the current study was aimed to develop and validate a novel multiplex qPCR to enable the specific and selective detection of the whole group of infectious
spp., including both pathogenic groups I and II and moreover, selectively discriminate between them. To fit the "fitness of purpose" for the specific detection of infectious
spp. and further discrimination between both pathogenic groups three target regions on the
gene were selected. These targets facilitated a broad and selective spectrum for the detection of all infectious
spp. with the exclusion of all saprophytic groups and the novel clade of environmental
spp. The analytical sensitivity (ASe) showed by the new assay also enables a wide window of detection for the agent at different stages of infection since the assay was able to efficiently detect at 95% of confidence ∼5 leptospires/reaction. From the evaluation of the analytical specificity (ASp) by
and
approaches, it was congruently revealed that the primers and probes selected only recognized the specific targets for which the assay was intended. Bayesian latent class analysis of performance of the new assay on 684 clinical samples showed values of diagnostic sensitivity of 99.8% and diagnostic specificity of 100%. Thus, from the evaluation of the analytical and diagnostic parameters, the new multiplex qPCR assay is a reliable method for the diagnosis of
spp.
•A triplex real time RT-PCR was developed for detection and differentiation of three genotypes of PHEV.•The developed triplex real time RT-PCR assay showed high specificity and sensitivity.•The ...triplex real time RT-PCR assay correctly genotyped clinical samples and is useful to monitor PHEV.
Porcine hemagglutinating encephalomyelitis virus (PHEV) is a single-stranded, positive-sense RNA virus. PHEV mainly causes two types of clinical manifestations representing vomiting and wasting and encephalomyelitis in piglets. However, our recent findings provide strong evidence that PHEV can also cause respiratory disease in older pigs. Genomic analysis of new PHEV strains identified in our former study further classifies PHEV into three genotypes. Detection and differentiation of these new mutants are critical in monitoring PHEV evolution in the field. In the present study, we report the development of a triplex real-time RT-PCR assay for detection and differentiation of three PHEV genotypes, 1, 2, and 3. Three sets of primers and probes were designed; one set of primers and probe targeting the conserved regions of the 3′ end nucleocapsid for detection of all three genotypes and another two sets of primers and probes targeting the regions of NS2 with different patterns of deletions for detection of both genotypes 1 and 3, or genotype 3 only. Genotype 1 was positive when two probe dyes showed signals, genotype 2 was positive when only one probe dye showed a signal, and genotype 3 was positive when all three probes showed signals. The detection limit of the developed triplex real-time RT-PCR was as low as 8 or 9 DNA copies for three sets of primers and probes. The specificity test showed no cross reaction with other porcine viruses. Positive field-samples were correctly typed by this new assay, which was further confirmed by DNA sequencing. The triplex real-time RT-PCR provides a rapid and sensitive method to detect and differentiate all three US genotypes of PHEV from clinical samples.
Although population viability analysis (PVA) can be an important tool for strengthening endangered species recovery efforts, the extent to which such analyses remain embedded in the social process of ...recovery planning is often unrecognized. We analyzed two recovery plans for the Mexican wolf that were developed using similar data and methods but arrived at contrasting conclusions as to appropriate recovery goals or criteria. We found that approximately half of the contrast arose from uncertainty regarding biological data, with the remainder divided between policy-related decisions and mixed biological-policy factors. Contrasts arose from both differences in input parameter values and how parameter uncertainty informed the level of precaution embodied in resulting criteria. Policy-related uncertainty originated from contrasts in thresholds for acceptable risk and disagreement as to how to define endangered species recovery. Rather than turning to PVA to produce politically acceptable definitions of recovery that appear science-based, agencies should clarify the nexus between science and policy elements in their decision processes. The limitations we identify in endangered-species policy and how PVAs are conducted as part of recovery planning must be addressed if PVAs are to fulfill their potential to increase the odds of successful conservation outcomes.
Because of exposure to environmental pollutants, infectious agents, and genetic predisposition, companion animals develop respiratory illnesses similar to those in humans. Older dogs of smaller ...breeds develop canine infectious respiratory disease, chronic bronchitis, and chronic obstructive pulmonary disease, with chronic lung infection, airway goblet cell hyperplasia and metaplasia, and mucus hypersecretion. Excessive mucus clogs airways, reduces gas exchanges, disables the mucociliary clearance, and reduces drug penetration. The Forkhead box protein A2 (FOXA2) is a key transcriptional regulator that maintains airway mucus homeostasis. Prior studies have shown that FOXA2 expression is frequently depleted in diseased human airways. Unfortunately, FOXA2 depletion has not been examined in dogs. Our current study indicated that both single bacterial infection by Pseudomonas aeruginosa and Bordetella bronchiseptica and polymicrobial infection by viral/bacterial pathogens depleted FOXA2 in canine airways, resulting in goblet cell hyperplasia and metaplasia and excessive mucus production. Furthermore, P. aeruginosa virulence factor pyocyanin activated the antagonistic STAT6 and epidermal growth factor receptor signalling pathways to inhibit FOXA2. Unravelling the mechanism of FOXA2 inactivation will hasten the development of non‐antibiotic therapeutics to improve mucociliary clearance of pathogens in canine airway.
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