Cricetomys Gambianus Research Articles

Sexual dimorphism between live body weight and morphological traits at various age categories of African giant rats (Cricetomys gambianus) in Ghana

Sexual dimorphism between live body weight and morphological traits at various age categories of African giant rats (Cricetomys gambianus) in Ghana

Ratting on wildlife crime: training African giant pouched rats to detect illegally trafficked wildlife

The illegal wildlife trade (IWT) is one of the largest global crime economies, directly threatening species and their habitats, and biodiversity, and indirectly the global climate, and countries’ economies. Syndicates operating within the IWT are often involved in trafficking of humans, weapons, and drugs. IWT takes place in large scale through international ports, with wildlife being smuggled inside shipping containers. Current methods to combat IWT and screen these shipping containers, such as X-ray scans, are expensive and time-consuming. Scent-detection animals present an innovative approach to combatting IWT, as animals may be better suited to distinguish between organic materials and less susceptible to visual concealment methods. Previous scent-detection work has largely focused on conservation dogs (Canis lupus familiaris). Here, we present a series of proof-of-principle studies training African giant pouched rats (Cricetomys ansorgei) to detect illegally trafficked wildlife. As initial proof-of-principle within a controlled laboratory environment, we trained rats (n=11) to detect the scent of pangolin scales (Manis spp.) and a threatened African hardwood (Dalbergia melanoxylon). In subsequent experiments, we trained these rats (n=10) to detect rhinoceros horn (family Rhinocerotidae), and elephant tusks (Loxodonta spp.). At the conclusion of these studies, rats (n=7) accurately identified all four target species (although ivory samples may have been cross-contaminated, and results should be interpreted with caution) while correctly rejecting non-target items commonly used by traffickers to conceal the presence of illicit material. Rats detected the presence of wildlife targets even when these were concealed in mixtures among non-target items. These results provide the foundation to train rats for scent-detection of illegally trafficked wildlife to combat IWT. The unique attributes of rats could allow them to complement existing screening technologies in the fight against IWT. Rats have low training and maintenance costs, flexibly work with multiple handlers, have a long lifespan, and a sophisticated sense of smell. Their small size also offers unique capabilities for the screening of shipping containers, such as being able to navigate densely packed areas or be lifted to assess contents of sealed containers by screening ventilation systems. Future directions include assessing operational feasibility of deploying rats at ports.

Leptospira infection of rodents captured at the slaughterhouses and their risk to public health in Unguja island, Tanzania

Background: Leptospira infection is an invasion of animal or human body with the pathogenic spirochete bacteria of the genus Leptospira resulting to a disease called leptospirosis. This study aimed to investigate Leptospira infection and the carrier status of rodents caught near slaughterhouses at Unguja Island, Tanzania. Methods: This cross-sectional study was conducted from January to April 2022 at Unguja Island to determine the seroprevalence of Leptospira infection in rodents captured in and around the slaughterhouse’s compounds. A total of 302 sera samples from four slaughterhouses were tested for anti-leptospiral antibodies using microscopic agglutination test (MAT) with a panel of 5 Leptospira serovars: Pomona, Lora, Hebdomadis, Grippotyphosa and Sokoine; and were considered positive at MAT titer ≥1:20. Chi-square test and the Fisher exact test were used to assess the statistical association between variables at a p value of < 0.05. Results: The overall seroprevalence of Leptospira infection in rodents was 10.6% (32/302). Individual rodent species had seroprevalence of 8.5% for Mus musculus, 0.0% for Mastomys natalensis, 20.8% for Rattus norvegicus, 9.3% for Rattus rattus and Cricetomys gambianus at 12.5%. However, the apparent seroprevalence in the individual slaughter facilities was 15.0% (15/100) Kinyasini, 10.4% (5/48) Mfenesini, 9.3% (5/54) Kisakasaka, and 7.0% (7/100) Muwanda. Conclusion: With over ten percent of rodents testing positive for Leptospira infection, it is crucial to implement rodent control measures to prevent the spread of the disease to those working in or around the slaughterhouses in Unguja Island.

Histomorphology and Histomorphometrics of the retina in Juvenile and Adult African Giant Rats (Cricetomys gambianus)

Aging is accompanied with various forms of functional ultrastructural and morphological changes in the eye, including the retina, leading to vision deterioration. However, age related retinal degenerative changes requires further elucidation especially as all previous studies on age-related change of the retina were done in mutant mouse strain models of hereditary retinal degenerations. The potential of using African giant rats (AGRs) as models for ageing in the eye, especially retina, was explored in this study. A total of 14 AGRs divided into two age groups (juvenile and adult) were used to study the histomorphology and histomorphometrics of the retina as well as retinal astrocyte morphology and heterogeneity. Histological findings included retinal atrophy and hypoplasia, with cellular swellings of neuronal cell populations and astrocytes soma and ramifications in the retina of adult compared to juvenile AGR. We suggest that AGR be used as animal model for translational research into normal aging process of the retina, as well as to elucidate the process of age-related neuronal cells loss.

Comparative Analysis of Consumer Preferences and Nutritional Composition of Wild and Farmed African Giant Rat. (Cricetomys gambianus) in Mampong Ashanti of Ghana

The African giant rat is one of Ghana's most common animals sought after as a source of meat (game). Local hunters use unhealthy means to hunt these animals, so attempts have been made to domesticate African giant rats in Ghana. Nevertheless, certain local consumers have articulated concerns, suggesting that wild giant rats' meat is more tender and leaner than those domestically farmed. The study was carried out to investigate consumer preference, sensory attributes, proximate composition, and acceptability of meats from wild and farmed African giant rats in Mampong Ashanti municipality in the Ashanti Region of Ghana. The study was conducted from November to December 2023. A survey was carried out among the residents of Asante Mampong using a structured questionnaire, with 500 individuals aged 20 years and older randomly selected to participate. Twenty (20) animals comprising ten (10) wild and ten (10) farmed African giant rats were used for the sensory and proximate analyses in a completely randomised design. Statistical Package for Social Sciences software was used for data analysis. Most participants (57%) preferred meat from wild African giant rats to their farmed counterparts, while only 7% indicated an equal fondness for both. Respondents with Islamic faith showed a preference for the meat of farmed African giant rats because of halal slaughter. The proximate composition of the raw giant rat meat was not affected by the sex since the values were very similar. However, wild African giant rat meat showed significantly (P =0.05) better proximate composition than the farmed ones. Except for meat colour and tenderness, meat from wild giant rats showed significantly (P = 0.05) better sensory properties than the meat from the farmed animals. This study concludes that meat sourced from giant African rats raised on farms is safer, has an impressive protein content, and has moderate fat levels.

Effects of Aqueous and Ethanolic Extracts of Ginger (Zingiber Officinale) Rhizome on Serum Progesterone Level and Markers of Oxidative Stress in African Giant Rat (Cricetomys Gambianus) in Captivity

Effects of Aqueous and Ethanolic Extracts of Ginger (Zingiber Officinale) Rhizome on Serum Progesterone Level and Markers of Oxidative Stress in African Giant Rat (Cricetomys Gambianus) in Captivity

The pattern of reproduction in the African giant pouched rat, Cricetomys gambianus, from Tanzania: unravelling the environmental triggers for breeding

Our research represents the first extensive study of the breeding behaviour and related environmental triggers of reproduction in the African giant pouch rat ( Cricetomys gambianus Waterhouse, 1840) in and around the equator throughout a whole year. We measured the gross morphology and detailed histology of both female and male rats, along with plasma steroid hormone levels. Contrary to other tropical-dwelling small mammals, the African giant pouch rat is a seasonal breeder; however, rainfall is not to be the primary cue of reproduction. Our study suggests that ambient temperature and photoperiod are the primary environmental cues of reproduction, with breeding occurring during the cooler months of the year, namely in the dry season. During the wet and hot season, which succeeds the dry season, there is an increase in the availability of quality food, which results in nursing mothers and weaned pups achieving a positive energy balance and increased body condition. This, in turn, increases pregnancy success and offspring survival. Climate change, particularly global warming, could harm the reproduction of African giant pouched rats as rising temperatures in and around the equator, including Tanzania, may impact their circannual reproductive cycle.

Machine Learning for Prediction of Tuberculosis Detection: Case Study of Trained African Giant Pouched Rats.

Technological advancement has led to the growth and rapid increase of tuberculosis (TB) medical data generated from different health care areas, including diagnosis. Prioritizing better adoption and acceptance of innovative diagnostic technology to reduce the spread of TB significantly benefits developing countries. Trained TB-detection rats are used in Tanzania and Ethiopia for operational research to complement other TB diagnostic tools. This technology has increased new TB case detection owing to its speed, cost-effectiveness, and sensitivity. During the TB detection process, rats produce vast amounts of data, providing an opportunity to identify interesting patterns that influence TB detection performance. This study aimed to develop models that predict if the rat will hit (indicate the presence of TB within) the sample or not using machine learning (ML) techniques. The goal was to improve the diagnostic accuracy and performance of TB detection involving rats. APOPO (Anti-Persoonsmijnen Ontmijnende Product Ontwikkeling) Center in Morogoro provided data for this study from 2012 to 2019, and 366,441 observations were used to build predictive models using ML techniques, including decision tree, random forest, naïve Bayes, support vector machine, and k-nearest neighbor, by incorporating a variety of variables, such as the diagnostic results from partner health clinics using methods endorsed by the World Health Organization (WHO). The support vector machine technique yielded the highest accuracy of 83.39% for prediction compared to other ML techniques used. Furthermore, this study found that the inclusion of variables related to whether the sample contained TB or not increased the performance accuracy of the predictive model. The inclusion of variables related to the diagnostic results of TB samples may improve the detection performance of the trained rats. The study results may be of importance to TB-detection rat trainers and TB decision-makers as the results may prompt them to take action to maintain the usefulness of the technology and increase the TB detection performance of trained rats.

Increased tuberculosis case detection in Tanzanian children and adults using African giant pouched rats.

African giant pouched rats, trained by Anti-Persoonsmijnen Ontmijnende Product Ontwikkeling (APOPO), have demonstrated their ability to detect tuberculosis (TB) from sputum. We assessed rat-based case detection and compared the mycobacterium bacillary load (MTB-load) in children versus adults. From January-December 2022, samples were collected prospectively from 69 Directly Observed Therapy (DOT) facilities' presumed TB patients. Using an average of five rats, APOPO re-evaluated patients with bacteriologically negative (sputum-smear microscopy or Xpert MTB/RIF) results. Rat-positive samples were tested using concentrated smear light-emitting diode microscopy to confirm TB detection before treatment initiation. The rats' identification of pulmonary TB is based on smelling TB-specific volatile organic compounds (VOCs) in sputum. Using STATA, Chi-square for oddsratio and confidence interval was calculated and evaluated: (1) the yield of rat-based TB detection compared to that of the health facilities; (2) rat-based TB detection in children versus adults; and (3) rats' ability to detect TB across MTB-loads and between children and adults. From 35,766 patients, 5.3% (1900/35,766) were smear-positive and 94.7% (33,866/35,766) were smear or Xpert-negatives at DOTS facility. Of those with negative results, 2029 TB cases were detected using rats, contributing to 52% (2029/3929 of total TB identified), which otherwise would have been missed. Compared to DOT facilities, rats were six-fold more likely to detect TB among Acid Fast Bacilli (AFB) 1+/scanty [90% (1829/2029) versus 60% (1139/1900), odds ratio, OR = 6.11, 95% confidence interval, CI: 5.14-7.26]; twice more likely to identify TB cases among children [71% (91/129) versus 51% (1795/3542), OR = 2.3, 95% CI: 1.59-3.42]; and twice more likely to identify TB cases among children with AFB 1+/scanty than adults with the same MTB-load [5% (86/1703) versus 3% (28/1067), OR = 2.0, 95% CI: 1.28-3.03]. Rats contributed over half of the TB cases identified in program settings, and children, especially those with a lower MTB-load, were more likely to be diagnosed with TB by rats. The chemical signatures, VOCs, were only available for adults, and further research describing the characteristics of VOCs in children versus adults may pave the way to enhance TB diagnosis in children.

Gross morpho-biometry, histometry and immunohistochemical investigations of pituitary gland in the juvenile and adult male African giant rats (Cricetomys gambianus)

This work was designed to investigate the morphometry and immunohistochemical features of pituitary glands in the African Giant Rats (AGR). Adult and juvenile AGR were sacrificed and their brains harvested, and the pituitary glands were carefully dissected. The weight, length and width of brains and pituitary glands were subsequently measured. Sections were prepared and stained using Haematoxylin and Eosin (H&E), Cresyl-violet and periodic-acid-Schiff (PAS) for histological analysis. Immunohistochemical analysis was carried out with Glial-Fibrillary-Acidic-Protein (GFAP) and Ionized-Calcium-Binding-Adapter-Molecule 1 (Iba1). Grossly, the AGR pituitary gland is a somehow laterally extended, saddle-shaped organ that is dorso-ventrally flattened. The gray-coloured adenohypophysis (anterior-pituitary lobe) was bigger in size than the whitish neurohypophysis (posterior-pituitary lobe) on physical examination. Histometrically, the adenohypophyseal length was noticeably greater than that of neurohypophysis in both juvenile and adult. Similarly, the adenohypophyseal and neurohypophyseal width in adult were found to be more than that of juvenile. Also, the histological staining of the neurohypophysis and adenohypophysis were distinct. In the neurohypophysis, fibrous and protoplasmic pituicytes were observed among fibres and Herring-bodies. Chromophils and chromophobes were identified in the adenohypophysis and melanotrophs in the intermediate lobe. Immunohistochemistry showed pituicytes in the neurohypophysis, which was positive with GFAP-antibody. With Iba1-antibody, the neurohypophysis expressed a stronger positive immunolabelling to microglia as compared to macrophages in the adenohypophysis. In conclusion, the gross and microscopic characteristics of pituitary glands of the AGR are found to be similar to other rodents and mammals. We recommend further study to compare morphometrical parameters between male and females of this model.

The Prevalence of Leptospira Serovars in African Giant Pouched Rats (Cricetomys spp.) from the Ngorongoro Conservation Area, Tanzania

Leptospirosis, also known as Weil’s disease, is a febrile tropical disease of humans and diverse animals. The maintenance hosts of the infectious pathogen, Leptospira spp., are primarily rodents, while other warm-blooded animals and some reptiles are secondary or transient hosts of this pathogen. African giant pouched rats (Cricetomys spp.) have been identified to be important maintenance hosts of pathogenic leptospires in the tropical and subtropical regions of the world. This study assessed the seroprevalence of Leptospira spp. in the African giant pouched rats of the Ngorongoro Conservation Area (NCA), Tanzania, where there is close human, domestic animal, and wildlife interaction. A total of 50 African giant pouched rats were sampled between July 2020 and December 2021. Blood sera were screened for specific leptospiral antibodies using a microscopic agglutination test (MAT), while urine and kidney tissues were examined for the pathogen and pathogen-specific genes using cultures and polymerase chain reactions (PCR), respectively. The pathogen detection varied from 0% in cultures to 6% via the MAT and 20% via PCR. The Fisher exact test was applied to compare positive cases detected through the diagnostic tests, and showed a significant difference in the indirect and direct detection of Leptospira serovars via the MAT and PCR. We conclude that pathogenic Leptospira serovar are found in the NCA and recommend that the NCA authority raises awareness of the existence of the Leptospira serovar in giant African pouched rats, and possibly other rodents. The NCA should initiate appropriate management strategies, including the guided disposal of household garbage, which is the major attractant of rodents to residential areas. Where necessary, the NCA should carry out limited rodent control and periodic monitoring of the pathogen carrier (rodent) populations.

Cerebellar and Olfactory Bulb Perturbations Induced by Vanadium Neurotoxicity in the African Giant Rat (Cricetomys gambianus, Waterhouse).

The African giant rat, AGR (Cricetomys gambianus) is a unique rodent known for its keen sense of smell which has enabled its use in the diagnosis of tuberculosis and demining activities in war torn countries. This keen sense of smell and the ability to navigate tight spaces are skills modulated by the olfactory bulb and cerebellum. While the brain is generally susceptible to environmental pollutants such as heavy metals, vanadium has predilection for these two brain regions. This work was thus designed to investigate the probable neurotoxic effect of vanadium on the neuronal cytoarchitecture of the cerebellum and olfactory bulb in this rodent. To achieve this, twelve adults male AGRs were divided into two groups (vanadium and control groups) and were given intraperitoneal injections of 3mg/kg body weight sodium metavanadate and normal saline respectively for 14 days. After which they were sacrificed, and brains harvested for histological investigations using Nissl and Golgi staining techniques. Results from our experiment revealed Purkinje cell degeneration and pyknosis as revealed by a lower intact-pyknotic cell (I-P) ratio, higher pyknotic Purkinje cell density and poor dendritic arborizations in the molecular layer of the cerebellum in the vanadium treated group. In the olfactory bulb, neuronal loss in the glomerular layer was observed as shrunken glomeruli. These neuronal changes have been linked to deficits in motor function and disruption of odor transduction in the olfactory bulb. This work has further demonstrated the neurotoxic effects of vanadium on the cerebellum and olfactory bulb of the AGR and the likely threat it may pose to the translational potentials of this rodent. We therefore propose the use of this rodent as a suitable model for better understanding vanadium induced olfactory and cerebellar dysfunctions.

Electrocardiography, Blood Pressure Measurements, Vital Parameters and Anaesthetic Indices in the African Giant Rat (Cricetomys Gambianus Waterhouse) Immobilized with Diazepam or Ketamine.

In spite of the increasing use and importance of the African giant rat (Cricetomys gambianus Waterhouse) in research, and other fields, like location of landmines, there is still not enough information on their physiology. In this study, we assessed the electrocardiogram, blood pressure, vital parameters and anaesthetic indices of the African giant rat (Cricetomys gambianus Waterhouse), both genders, using diazepam or ketamine as chemical restraints. A total of 24 adult African Giant Rats (AGR), 12 males and 12 females were used in this experiment. The animals were divided into two groups of twelve animals each (6 males and 6 females). One group was assessed for the effect of diazepam, and the other group ketamine. Diazepam (Roche®, Switzerland) was administered intraperitoneally at a dose rate of 7.5 mg/kg, while ketamine was administered intraperitoneally at a dose rate of 45 mg/kg. Parameters measured were recorded from the time desirable sedation was achieved, and every 15 minutes till the animal was awake. Animals administered diazepam took a longer time to sleep or achieve desirable sedative state, a longer time to respond to stimuli before waking up fully and a longer time to be fully awake, relative to ketamine-induced sedation. Ketamine caused a continuous increase in respiratory rate and blood pressure, while diazepam caused a continuous decrease in the respiratory rate. The electrocardiogram showed tachycardia throughout the experiment with the use of both drugs, although this was more pronounced with the use of diazepam, causing a decrease in QRS interval and a decrease in QT interval. Gender differences were observed in most parameters measured. The results obtained gave baseline values for electrocardiogram and blood pressure readings, while also detailing the changes and gender differences observed with sedation. In addition, results indicated ketamine is best used for short procedures and diazepam at a higher dose used for procedures requiring longer time in the African giant rat.

Histomorphological Changes in the Ovary of African giant rat (Cricetomys gambianus, WATERHOUSE – 1840) subjected to Different light/dark cycles

The present study was undertaken to investigate the effect of photoperiod on the ovary of African giant rats (AGR), Cricetomys gambianus. A total of 15 captive African giant rats from the wild served as subjects. The rats were randomized into three photoperiodic treatment groups of five rats each. Groups I, II and III were the control (12 hours of darkness (12D), 12 hours of light (12L); total darkness (24D: 0L) and total light (0D: 24L), respectively. The rats were humanely euthanized, and ovaries collected at 4 weeks and 8 weeks of sacrifice for routine histological examination and histomorphometry. Cystic follicles were observed in the ovaries of AGR exposed to constant light. Again, continuous lighting exposure significantly increased (p < 0.05) the ovarian follicular diameter when compared with the control. In conclusion, the findings of this study indicate that continuous light exposure could have significant effect in follicular cyst formation in AGR.

Neuropathological profile of the African Giant Rat brain (Cricetomys gambianus) after natural exposure to heavy metal environmental pollution in the Nigerian Niger Delta.

Pollution by heavy metals is a threat to public health because of the adverse effects on multiple organ systems including the brain. Here, we used the African giant rat (AGR) as a novel sentinel host to assess the effect of heavy metal accumulation and consequential neuropathology upon the brain. For this study, AGR were collected from distinct geographical regions of Nigeria: the rain forest region of south-west Nigeria (Ibadan), the central north of Nigeria (Abuja), and in oil-polluted areas of south Nigeria (Port-Harcourt). We found that zinc, copper, and iron were the major heavy metals that accumulated in the brain and serum of sentinel AGR, with the level of iron highest in animals from Port-Harcourt and least in animals from Abuja. Brain pathology, determined by immunohistochemistry markers of inflammation and oxidative stress, was most severe in animals from Port Harcourt followed by those from Abuja and those from Ibadan were the least affected. The brain pathologies were characterized by elevated brain advanced oxidation protein product (AOPP) levels, neuronal depletion in the prefrontal cortex, severe reactive astrogliosis in the hippocampus and cerebellar white matter, demyelination in the subcortical white matter and cerebellar white matter, and tauopathies. Selective vulnerabilities of different brain regions to heavy metal pollution in the AGR collected from the different regions of the country were evident. In conclusion, we propose that neuropathologies associated with redox dyshomeostasis because of environmental pollution may be localized and contextual, even in a heavily polluted environment. This novel study also highlights African giant rats as suitable epidemiological sentinels for use in ecotoxicological studies.

Scent detection of Brucella abortus by African giant pouched rats (Cricetomys ansorgei)

BackgroundBrucellosis is a contagious zoonosis caused by bacteria of the genus Brucella. While the disease has been eradicated in most developed countries, it remains endemic in sub–Saharan Africa where access to reliable diagnostics is limited. African giant pouched rats (Cricetomys ansorgei) have been trained to detect the scent of Mycobacterium tuberculosis to increase case detection in sub-Saharan Africa. Given the similar diagnostic challenges facing brucellosis and tuberculosis, we explored the feasibility of training African giant pouched rats to detect Brucella.ResultsAfter 3 months of training, rats reliably identified cultured Brucella, achieving an average sensitivity of 93.56% (SD = 0.650) and specificity of 97.65% (SD = 0.016). Rats readily generalized to novel, younger Brucella cultures that presumably generated a weaker volatile signal and correctly identified at least one out of three fecal samples spiked with Brucella culture during a final test of feasibility.DiscussionTo our knowledge, these experiments are the first to demonstrate Brucella emits a unique odor profile that scent detection animals can be trained to identify. Importantly, cultured E. coli samples were included throughout training and test to ensure the rats learned to specifically identify Brucella bacteria rather than any bacteria in comparison to bacteria-free culture medium. E. coli controls therefore served a crucial function in determining to what extent Brucella abortus emits a unique odor signature. Further research is needed to determine if a Brucella-specific volatile signature is present within clinical samples. If confirmed, the present results suggest trained rats could serve as a valuable, novel method for the detection of Brucella infection.

Epidemiology and molecular study of Leptospira spp. in bats and rodents in the Republic of Guinea

Introduction: Leptospirosis is a zooanthroponosis caused by spirochete bacteria called leptospire of the genus Leptospira. Objective: To contribute to the knowledge and circulation of the Leptospira germ in humans in the Republic of Guinea. Methods: This prospective and descriptive cross-sectional study lasted 18 months, from June 2019 to December 2020. Results: 687 samples, including 388 bat kidney tissues and 299 kidney tissues from captured rodents, were analysed at IRBAG's Guineo-Russian laboratory. The molecular diagnostic technique (RT-qPCR) and sequencing were carried out. Among rodents, 15 species were captured in the various administrative regions of Guinea: Mastomys natalensis, Mastomys erythroleucus. Mastomys sp, Praomys daltoni, Praomys rostratus, Praomys sp, Rattus rattus, Mus musculus, Mus musculoides, Mus sp, Lemmiscomys striatus, Gerbilliscus guineae, Cricetomys gambianus, Crocidura olivieri, Crocidura sp. The N’zérékoré region recorded the highest number of captures 226 (87 Mastomys natalensis ,61 Mus musculus, 46 Crocidura sp. 26 Rattus rattus, 5 Crocidura olivieri, 1 Mus sp. ), followed by the Kindia region with 66 cases (25 Rattus rattus ,18 Mastomys sp, 10 Mastomys erythroleucus, 6 Mus musculus, 2 Praomys daltoni, 2 Praomys sp, 2 Mus musculoides, 1 Praomys rostratus, 1 Lemmiscomys striatus, 1 Gerbilliscus guineae, 1 Cricetomys gambianus), the Faranah region with 4 cases (3 Mus musculoides,1 Mastomys sp.). The Mamou, Boké and Labé regions recorded no cases. Sixteen species of bats were captured and tested: Rousettus aegyptiacus, Lissonycteris angolensis, Epomophorus gambianus, Hipposideros jonesi, Hipposideros ruber, Hipposideros abae, Hipposideros sp., Rhinolophus sp., Chaerephon sp.., Chaerephon major, Chaerephon pumilus, Mops condylurus, Mops sp., Nycteris sp., Scotophilus leucogaster, Miniopterus sp. The Kindia region recorded the highest number of positive carriers 184 (102 Hipposideros ruber, 14 Lissonycteris angolensis, 13 Hipposideros jonesi,13 Mops condylurus,12 Hipposideros sp., 8 Rousettus aegyptiacus,8 Chaerephon pumilus, 5 Hipposideros abae,3 Scotophilus leucogaster,3 Miniopterus sp.,2 Rhinolophus sp.,1 Mops sp.), the N'Zérékoré region 134 cases (1 Lissonycteris angolensis, 1 Chaerephon sp.,41 Chaerephon major, 6 Chaerephon pumilus, 94 Mops condylurus,1 Mops sp,1 Nycteris sp.),the Boké region 52 cases (50 Hipposideros ruber, 2 Rhinolophus sp.),the Faranah region 7 cases (7 Epomophorus gambianus), the Mamou and Labé regions recorded 0 cases each. Mastomys sp. 3/17, Praomys daltoni 0/2, Praomys rostratus 1/1, Rattus rattus 1/13, Mus musculus 0/5, Mus musculoides 0/0, Crocidura olivieri), the Nzérékoré region with 4 positive cases out of 129. (Mastomys natalensis 1/37, Rattus rattus 1/14, Crocidura sp.2/30), the Faranah region recorded 0 positive cases out of a total of 4 (Mastomyssp. 0/1, Mus musculoides 0/3) and the Boké region 0 cases out of a total of 0. Mastomus natalensis, number of specimens 56 including 14 positive cases, i.e. 6.9%; P.daltoni, number of specimens 3 including 2 positive cases, i.e. 1.43%; Praomus sp, number of specimens 7 including 0 positive cases; Rattus rattus, number of specimens 75 including 1 positive case, i.e. 0.48%; Mus musculus, number of specimens 3 including 0 positive cases; P.fallax, number of specimens 1 including 0 positive cases; L.sikapusi, number of specimens 1 including 0 positive cases; Crocidura sp, number of specimens 2 of which 0 positive; S.leucogaster, number of specimens 32 of which 0 positive; T. thersites, number of specimens 23 of which 0 positive; N.hispida, number of specimens 4 of which 0 positive; E.helvum, number of specimens 2 of which 0 positive. Sequencing yielded fragments of the LiP32 gene were isolated from all positive samples. Analysis established the identity of the samples with the L. interrogans genome. Conclusion: The results obtained prove that the leptospirosis pathogen does circulate in the Republic of Guinea in both rodents and bats.

Light exposure impairs hematological characteristics and oxidative stress markers in male African giant pouched rat (Cricetomys gambianus) reared in captivity

Light exposure impairs hematological characteristics and oxidative stress markers in male African giant pouched rat (Cricetomys gambianus) reared in captivity

Diversity and Density of Small Mammal Species with Different Seasons and Habitats in Federal University Gashua, Yobe State, North-east Zone of Nigeria

The study examined diversity and density of small mammal species with different seasons and habitats in Federal University Gashua, Yobe State, North-East, Nigeria. The university environment was divided in to four (4) habitat types, namely; University residential area (URA), Acacia woodlot (AWL), Lake Area (LA) and Farm Land (LF) were used for the study. Small Mammal species survey was carried out for the period of six (6) months from August to October, 2022 (wet season) and January, to March, 2023 (dry season). Capture Mark–Recapture (CMR) and indirect observations methods were adopted; Survey was conducted using spring door traps of different sizes set at the habitat types during late evening hours 6:00 pm and checked in the morning hours from 6:00-8:30am for four (4) days per week with each habitat types being visited one day per week, making total of (96) man-days. Each habitat type was visited twice a day (morning and evening) which gave a total of (65;60) trapping night in both wet and dry seasons, the number decreased to 60 trapping night in the dry season was due to the wearing a way of vegetation cover. (32) Visits per habitat types and one (1) night survey per month. A total of ten (10) species of small mammals belonging to ten (10) families and seven (7) orders were recorded in the study. African Hedgehog Atelerix albiventris and White toothed shrew Crocidura flavescens were the most occurring species across The findings of the study shows that the overall diversity index was (1.692), where Four-toed hedgehog Atelerix albiventris had the highest species diversity90.363) and estimated population density of (64.44) followed by Giant pouched rat Cricetomys gambianus with (0.277; 0.018) respectively, Cape hare Lepus capensis and Mongoose Herpestes ichneumon who’s having the lowest diversity of (0.017) with (0. 564) density each in the study area. The month of February has higher number of captured percentage with (24%) in dry season, followed by October with (19%) in the wet season, the lowest capture percentage occurred with August (14%) in the wet season. University Residential Area had more number of individual species having (37.82 %), while Farm land had the least captured percentage of(16.85%).The trap success in both wet season and dry season’s period were (33.04%; 21.67%)respectively. Habitat alteration and destruction due to ongoing constructions project, mainly for university deployment might have accounted for small mammal species low diversity and density in Federal University Gashua.

A Review on Monkeypox

Monkeypox is a re-emerging zoonotic disease caused by a DNA virus that belongs to the orthopox virus genus of the Poxviridae family. After the eradication of smallpox in 1980, monkeypox has gradually emerged as the most important orthopox virus from a public health perspective. Monkeypox typically causes fever, chills, rash, and lesions on the face or genitals. MPXV (monkeypox virus) is considered a large virus that measures about 200–250 nm with the appearance “brick-like” or ovoid shape, The virus’s original source is wild animals. It can be found in a variety of mammals including squirrels, mangabey monkeys, and Gambian rats. Viral transmission can occur through direct and indirect contact with live or dead animals, including handling wild game, a bite or scratch, or contact with fluids or lesions from an infected animal. Human-to-human transmission likely occurs through contact with lesions, body fluids, contaminated bedding or clothing, and exposure to respiratory droplets from infected persons. Animal-to-human transmission of MPXV may occur via animal bites or scratches by infected small mammals, including rodents and nonhuman primates, or through the consumption of bush meat. Any patient with a fever and disseminated vesicular or pustular rash should be immediately placed on airborne and contact precautions, as these are the classic symptoms of Orthopox virus infections. smallpox antivirals with poxvirus activity, such as cidofovir, brincidofovir, and tecovirimat, are active against the monkeypox virus. Monkeypox is usually a self-limiting disease; however, new-borns, children, and people with underlying immune deficiencies may be at risk of more serious illness and death.