Application of a multidisciplinary approach to the systematics of Acomys (Rodentia : Muridae) from northern Tanzania

The systematic status and geographic distribution of spiny mice of the genus Acomys I. Geoffroy, 1838 in northern Tanzania is uncertain. This study assesses the systematic and geographic distribution of Acomys from northern Tanzania using a multidisciplinary approach that includes molecular, cytogenetic, traditional and geometric morphometric analyses, and classical morphology of the same individuals. The molecular analysis was based on 1140 base pairs (bp) of the mitochondrial cytochrome b and 1297 bp of the nuclear interphotoreceptor retinoid binding protein (IRBP) gene sequences. These data were subjected to phylogenetic analyses using Maximum likelihood, Bayesian, Maximum parsimony, and Minimum evolution analyses. The cytogenetic analysis included G-banding of metaphase chromosomes. The morphometric analyses included univariate and multivariate analyses of traditional morphometric measurements of the cranium and mandible, and of geometric morphometric two-dimensional landmarks of the dorsal, ventral, and lateral views of the cranium, and lateral view of mandible that included thin-plate spline (TPS) analysis. The classical morphology included examination of external, cranial and mandibular morphology. Results of all these multidisciplinary analyses were congruent and provide evidence for the occurrence of two sympatric species of Acomys in northern Tanzania, namely, the previously recorded A. wilsoni (2n = 62) and a newly recorded A. cf. percivali (2n = 58). These results that also represent the first reported mitochondrial cytochrome b and nuclear IRBP gene sequences and karyotype for A. cf. percivali, increases the number of species known to occur in Tanzania from four to five. However, the mitochondrial cytochrome b data that included GenBank sequences from the type locality in Kenya suggest that A. wilsoni may not be monophyletic. Ecologically, the two species seem to partition their niches with A. cf. percivali being found in well-covered habitats with thorn bushes, rocky and mountainous areas, and A. wilsoni being found in open semi-arid grasslands as well as in rice fields. The two species appear to be isolated by complex natural barriers formed by the Great East African Rift Valley whose geological features have generally been associated with active rodent speciation. However, the present results need further multidisciplinary investigation involving extensive sampling and examination of topotypical material. CopyrightDissertation (MSc)--University of Pretoria, 2008.Zoology and Entomologyunrestricte

Detection Rats Technology for Diagnosis of Tuberculosis in High-Risk Populations

Prevalence of tuberculosis (TB) in prisoners in Tanzania and other sub-Saharan African countries is considered to be higher than in other populations thus prisons are important source of TB transmission. Control of TB in prisons through appropriate screening and diagnosis is challenging in most low-income countries such as Tanzania that is among world’s 22 countries with high burden of TB. Commonly used TB diagnostic test (smear microscopy) have low sensitivity, and most advanced GeneXpert method is rather expensive for developing countries. SUA-APOPO TB detection rats’ technology is most promising and increases TB case detection by over 40% in hospitals in Dar es Salaam Tanzania and Maputo Mozambique. This paper reports on improved TB detection in a selected prison in Tanzania using TB detection rats. Sputum samples (n = 11,424) were collected from 5,840 patients whom 3,491 were men, 2,349 were women. Of these, 386 patients were children altogether seeking diagnosis of TB at Ukonga prison dispensary from January 2013 to October 2015) and Keko prison dispensary from February to October 2015). Samples were routinely examined by Ziehl Neelsen (ZN) staining and later tested by rats APOPO TB laboratory, Sokoine University of Agriculture, Morogoro. Rats’ positive samples were concentrated and confirmed by fluorescent microscopy (LED-FM) or ZN microscopy. A total of 709 individuals (12%) were diagnosed as smearpositive TB by the prison hospital, whereas rats detected an additional 302 TB patients. This increased the case detection in the prison population by 43%. The use of rats’ technology increased the prevalence of smear-positive TB in prisons from 12% to 17.3% (n = 1,011) that is higher than prevalence reported in prisons elsewhere using microscopy. This finding shows that detection rats’ technology can help reduce the burden of TB in developing countries. There is need to expand application of this technology to other risk populations including miners.This technology can improve workforce, livelihood and socio-economy by reducing TB related expenses

Using giant african pouched rats to detect human tuberculosis: a review

Despite its characteristically low sensitivity, sputum smear microscopy remains the standard for diagnosing tuberculosis (TB) in resource-poor countries. In an attempt to develop an alternative or adjunct to microscopy, researchers have recently examined the ability of pouched rats to detect TB-positive human sputum samples and the microbiological variables that affect their detection. Ten published studies, reviewed herein, suggest that the rats are able to detect the specific odor of Mycobacterium tuberculosis, which causes TB, and can substantially increase new-case detections when used for second-line TB screening following microscopy. Further research is needed to ascertain the rats' ability to detect TB in children and in HIV-positive patients, to detect TB when used for first-line screening, and to be useful in broad-scale applications where cost effectiveness is a major consideration

Domestic Cat (Felis silvestris catus) Urine Odour as a Potential Rodent Management Strategy

The aim of this study was to investigate the effects of cat urine odour extract on rodent pest species to reduce crop losses. Cat urine from the captured cats was drawn using cat catcher. Urinary catheter was inserted into the urethra up to the urinary bladder and a syringe attached to the urinary catheter was used to draw urine which was stored in universal bottles at a temperature below -20ºC. The stored cat urine was directly bound to the maize starch by slowly mixing the urine with the starch until dough was formed which was then granulated. The granules were dried at room temperature and packed in a tight closed jar. Mastomys natalensis of 25 – 40 g were used in this study. Wild captured individuals were acclimatized in a room for 7 days prior to experiment by providing them with food and water. The effect of cat urine odours on rodent pest species was studied in a single box. Camera traps were set at the top of each room in order to monitor rodents’ activities. Our Findings suggests that cat urine odour has a potential to repel rodent pest species whereas female cat urine was more effective than male cat urine. However, more investigations are needed to evaluate its effectiveness under field conditions

Leptospira Serovars for Diagnosis of Leptospirosis in Humans and Animals in Africa: Common Leptospira Isolates and Reservoir Hosts

The burden of leptospirosis in humans and animals in Africa is higher than that reported from other parts of the world. However, the disease is not routinely diagnosed in the continent. One of major factors limiting diagnosis is the poor availability of live isolates of locally circulating Leptospira serovars for inclusion in the antigen panel of the gold standard microscopic agglutination test (MAT) for detecting antibodies against leptospirosis. To gain insight in Leptospira serovars and their natural hosts occurring in Tanzania, concomitantly enabling the improvement of the MAT by inclusion of fresh local isolates, a total of 52 Leptospira isolates were obtained from fresh urine and kidney homogenates, collected between 1996 and 2006 from small mammals, cattle and pigs. Isolates were identified by serogrouping, cross agglutination absorption test (CAAT), and molecular typing. Common Leptospira serovars with their respective animal hosts were: Sokoine (cattle and rodents); Kenya (rodents and shrews); Mwogolo (rodents); Lora (rodents); Qunjian (rodent); serogroup Grippotyphosa (cattle); and an unknown serogroup from pigs. Inclusion of local serovars particularly serovar Sokoine in MAT revealed a 10-fold increase in leptospirosis prevalence in Tanzania from 1.9 % to 16.9 % in rodents and 0.26% to 10.75 % in humans. This indicates that local serovars are useful for diagnosis of human and animal leptospirosis in Tanzania and neighbouring countries

Using giant African pouched rats to detect tuberculosis in human sputum samples: 2010 findings

Giant African pouched rats previously have detected tuberculosis (TB) in human sputum samples in which the presence of TB was not initially detected by smear microscopy. Operant conditioning principles were used to train these rats to indicate TB-positive samples. In 2010, rats trained in this way evaluated 26,665 sputum samples from 12,329 patients. Microscopy performed at DOTS centers found 1,671 (13.6%) of these patients to be TB-positive. Detection rats identified 716 additional TB-positive patients, a 42.8% increase in new-case detection. These previously unreported data, which extend to over 20,000 the number of patients evaluated by pouched rats in simulated second-line screening, suggest that the rats can be highly valuable in that capacity

Leptospira seroprevalence among ugandan slaughter cattle: comparison of sero-status with renal Leptospira infection

Despite evidence of both human and animal; Leptospira; exposures in Uganda, the epidemiology of the disease is still not well-investigated. Contact with animals and their environments have been pointed out as potential source of infection with; Leptospira; species in humans; and cattle may be an important reservoir in Uganda. In this cross-sectional study, we estimated the prevalence of anti-; Leptospira; antibodies by the standard microscopic agglutination test (MAT); and associated risk factors among slaughtered cattle. We also compared the performance of the MAT used in this study against a; lipL32; based real time PCR (qPCR) assay previously conducted on the kidneys and urine of the same slaughter cattle as tested in this reported study. Of 500 cattle sampled, 27.8% (95% CI 23.9-32.0) tested positive (titer ≥ 100) to at least one; Leptospira; serovar, with the majority of seropositive cattle reacting to serovars Tarassovi (sg Tarassovi) (11.6%), Sejroe (Sg Sejroe) (7.8%), and Australis (Sg Australis) (5.2%). Older animals had 2.8 times (95% CI 1.0-8.2,; p; -value 0.055) greater odds of being seropositive than younger ones (<1.5 years). The sensitivity and specificity of the MAT over the qPCR were 65.9% (95% CI 50.1-79.5) and 75.9% (95% CI 71.7-79.7), respectively; with a negative predictive value of 95.8% and positive predictive value of 20.9%. In conclusion, slaughter cattle in this study were significantly exposed to pathogenic; Leptospira; species of mainly the Tarassovi, Sejroe, and Australis serogroups, with seroprevalence being higher among older cattle. The high specificity and negative predictive value of MAT as used in this study when compared to the qPCR assay may imply a rather strong association between seronegativity and absence of renal; Leptospira; infection. However, MAT predictability for renal; Leptospira; infection may be interpreted cautiously since predictive values of diagnostic tests are dependent on prevalence

The pattern of reproduction in the mole-rat Heliophobius from Tanzania : do not refrain during the long rains!

The genus Heliophobius comprises of at least six cryptic, topotypical species in the Heliophobius argentocinereus species complex. The current study investigated the breeding patterns of a wildcaught population from Tanzania where the putative species H. emini resides. Individuals were collected on a monthly basis for an entire calendar year. Assessment of foetus presence, gonadal histology, reproductive tract morphometrics in combination with gonadal steroid (plasma progesterone and oestradiol-17β in females and testosterone in males) measurements and field observations revealed that rainfall is important for the onset of breeding. The results further confirmed that breeding is limited to a single, yearly reproductive event synchonised to the long rainfall pattern. The distinct breeding peak in July is associated with an elevation in gonadal mass, increase in concentrations of reproductive hormones and presence of Graafian follicles and corpora lutea in the ovaries of females. These reproductive parameters coincided with the end of the long rainfall period, whereas presence of young in the maternal burrow system corresponded with the start of the short rainfall of East Africa. These findings confirm Heliophobius has a single breeding opportunity each year, and this species is therefore vulnerable to any changes that may impact their climatically attuned breeding patterns.MKN was sponsored by a student bursary from DAAD in Germany. NCB acknowledges funding from the South African DST/NRF SARChI Chair for Mammal Behavioural Ecology and Physiology, University of Pretoria.http://www.nrcresearchpress.com/journal/cjzhb2017Mammal Research InstituteZoology and Entomolog

Selected Endemic Zoonoses in Pigs Presenting for Slaughter in Kampala, Uganda

Leptospirosis, brucellosis, and Q fever (coxiellosis) are bacterial zoonoses that cause acute febrile illness in people as well as reproductive losses in pigs. Pig keeping is an increasingly important livelihood to millions of smallholder farmers in Uganda because of exponential increases in demand for pork. The prevalence of leptospirosis and Q fever in pigs is unknown, and the few studies of porcine brucellosis have estimated a range of seroprevalence. Therefore, we undertook a prevalence survey of leptospirosis, brucellosis, and Q fever in pigs using quantitative real-time PCR to determine the potential importance of these zoonoses to the growing pig sector in Uganda. Six hundred forty-nine pigs were sampled in 2015–2016 at an urban pork slaughterhouse. Ten percent of pigs (n = 68) had leptospiral DNA in either their kidney or reproductive tissue. In adjusted analyses, variables predictive of leptospiral status included female sex (odds ratio [OR]: 2.37,P< 0.01) and pigs sampled in March 2016 (OR: 2.23,P= 0.02) and October 2016 (OR: 0.30,P= 0.04). DNA fingerprinting revealed circulation of at least four distinct serovars in these pigs. Brucella spp. and Coxiella burnetii DNA were not detected in any sampled pig. This is the first report of widespread circulation of pathogenic Leptospira spp. in pigs in Uganda, suggesting that leptospirosis likely has a greater impact on the health of pigs than was previously recognized. Pig farmers, pig traders, and slaughterhouse workers may be at greatest occupational risk because of their direct contact with infective leptospires in aborted fetuses, bodily fluids, and other tissues

Phylogeography and cryptic diversity of the solitary-dwelling silvery mole-rat, genus Heliophobius (family: Bathyergidae)

Alongside the eusocial naked mole-rat, Heterocephalus glaber, Heliophobius argenteocinereus represents the second oldest lineage within the African mole-rat family Bathyergidae, and phylogenetically intermediate between the East African Het. glaber and the South African genera Bathyergus and Georychus. Across its geographic range, Hel.. argenteocinereus is widely distributed on both sides of the East African Rift System (EARS), and is a key taxon for understanding the phylogeographic patterns of divergence of the family as a whole. Phylogenetic analysis of 62 mitochondrial cyt b sequences, representing 48 distinct haplotypes from 26 geographic locations across the range of Heliophobius, consistently and robustly resolved six genetically divergent clades that we recognize as distinct evolutionary species. Early species descriptions of Heliophobius were synonymized into a monotypic taxonomy that recognized only Hel. argentocinereus. These synonyms constitute available names for these rediscovered cryptic lineages, for which combined morphological and genetic evidence for topotypical populations endorses the recognition of six to eight distinct taxa. Bayesian estimates of diver- gence times using the fossil Proheliophobius as a calibration for the molecular clock suggest that the adaptive radiation of the genus began in the early Miocene, and that cladogenesis, represented in the extant species, reflects a strident signa- ture of tectonic activity that forged the principal graben in the EARS.SYNTHESYS grant (BE-TAF-289), grants from the National Research Foundation, the University of Pretoria South Africa (to NCB) and the ERANDA and Bay Foundations (FC).http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1469-7998ab201