Anti-trypanosomal activity of secnidazole in vitro and in vivo

Purpose: To evaluate the anti-trypanosomal effect of secnidazole (SEC) in vitro and in vivo. Methods: The dose-response effect of SEC in Trypanosoma b. brucei infected rats was evaluated in five groups of rats (n = 5). Group A was infected but untreated; B was given diminazene aceturate (DA) (3.5 mg/kg) intraperitoneally, while groups C, D and E received orally 400, 800 and 1600 mg/kg of SEC, respectively. The effect of a combination therapy of SEC and DA was studied in 7 groups of rats (n =5). Group 1 was infected but untreated; groups 2 – 7 were treated with DA (3.5 mg/kg), while groups 3 – 7 received in addition to DA, increasing double doses of SEC (50 – 800 mg/kg).Results: The MIC of SEC and DA were 1.4 and 0.0021 mg/ml respectively. SEC dose-dependently and significantly (p < 0.05) lowered parasitemia from day 2 post-treatment (PT) compared with infected untreated rats. Parasitemia was cleared 3 days PT in all combination groups and 5 days PT in DA group. Relapse of infection occurred in Group 2, 13 days PT, and 16 and 27 days PT in Groups 3 and 4 respectively. There was no relapse of infection in Groups 5 – 7 up to 70 days PT.Conclusion: These results suggest that SEC possesses some degree of  anti-trypanosomal effect, and that combination therapy of SEC and DA was superior to DA alone.Keywords: Trypanosoma, Secnidazole, Diminazene aceturate, Anti-trypanosomal, Combination therap

Disposition kinetics of ceftriaxone and determination of its therapeutic dose in dogs

Purpose: To evaluate the disposition kinetics of ceftriaxone (CFZ) in dogs with a view to determining its therapeutic dose and dosing frequency.Methods: Twelve (12) Basenji dogs (n = 4), divided into 3 groups (A, B and C), were used for the study. Ceftriaxone was administered intramuscularly at doses of 12.5, 25, and 50 mg/kg once to groups A, B and C respectively. Plasma CFZ concentration was determined by agar well diffusion assay at 0.25, 0.5, 1, 2, 3, 4, 6, 8, 10, 12, and 24 h post-treatment, and the pharmacokinetic parameters were determined.Results: Intramuscular injection of CFZ to dogs resulted in rapid absorption, distribution and elimination (p < 0.05). The elimination half-life was short and did not change significantly with increase in dose. Serum concentration of CFZ changed significantly (p < 0.05) with increase in dose of CFZ. The maximum serum concentration (Cmax, 15.00 ± 1.18, 141.37 ± 15.87 and 259 ± 5.21 μg/mL) for groups A, B and C respectively were significantly (p < 0.05) different. The steady state CFZ concentrations; 0.94, 8.81 and 16.19 μg/mL for groups A, B and C, respectively, were significantly (p < 0.05) different. However, there was no significant difference in the time to reach steady state concentrations (Tmax, 00±0.021, 4.00±0.10 and 4.30±0.12 for groups A, B and C respectively). The therapeutic dose of CFZ was therefore determined to be 25 – 50 mg/kg every 4 h.Conclusion: Ceftriaxone undergoes rapid elimination in dogs with a short elimination half-life, thus making it an inconvenient prescription for out-patients in veterinary clinics. Keywords: Ceftriaxone, Pharmacokinetic profile, Dogs, Therapeutic dose, Veterinary clini

Comparative evaluation of the chemotherapeutic efficacies of two salts of diminazene aceturate in Trypanosoma brucei brucei infected dogs

Purpose: To compare the anti-trypanosomal efficacies of 4,4-(diazoaminedibenzamidinetrihydrate) diacetate (4,4-DDBT) and 4,4-(diazoamino) benzamidine (4,4-DB) in experimental canine trypanosomosis. Methods: The efficacies of 4,4-DDBT and 4,4-DB were evaluated in 4 groups of dogs (n = 3) designated A-D. Group A was normal control without infection or drug treatment, group B did not receive any drug treatment but was infected with Trypanosoma brucei brucei, while groups C and D were infected with T. b. brucei and treated with 4,4-DDBT(3.5 mg/kg) and 4,4-DB (3.5 mg/kg), respectively. Results: The incubation period of the infection was 6 - 9 days post-infection. Treatment of the dogs with 4,4-DDBT led to zero parasitaemia 48 h post-treatment, while there was only a decrease in parasitemia to log 6 in 4,4-DB-treated dogs. Resurgence of parasite into the blood stream occurred in 4,4-DDBTtreated dogs 6 days after initial parasite clearance. Blood analyses post-treatment revealed elevated leucocytes and lymphocytes in 4,4-DB-treated dogs (p < 0.05). Packed cell volume was also observed to be higher in 4,4-DDBT-treated group when compared to 4,4-DB group (p < 0.05). Conclusion: These findings suggest that 4,4-DDBT is more efficacious in the clinical management of canine trypanosomosis caused by T. b. brucei. However, it does not prevent relapse of infection. Based on these findings, therefore, 4,4-DDBT should be the diminazene salt of choice when indicated in the clinical management of T. b. brucei infection in dogs

Clinico-toxicological effects of ceftriaxone after intramuscular administration of graded doses in Basenji dogs

Purpose: The recent ceftriaxone-induced anaemia and mortalities at the dose of 50 mg/kg in Veterinary Teaching Hospital, University of Nigeria prompted this study which sought to assess the clinicotoxicological effects of ceftriaxone (CFZ) after intramuscular administration of graded doses in Basenji dogs.Methods: The effects of CFZ on the haematological indices, physiological parameters, liver and kidney functions were assessed in 4 group of dogs (n = 4) designated A – D. They were given CFZ intramuscularly for 21 days at doses of 12, 25 and 50 mg/kg for groups A, B, C, respectively, while thecontrol (group D) received the diluent (lignocaine 0.2 mL)Results: The mean pulse and heart rate of dogs in group C were significantly (p < 0.05) higher than those of group A, B and D. Significant (p < 0.05) decrease in red blood cell count (RBC), haemoglobin concentration (Hb) and packed cell volume (PCV) was observed in group C on days 7 and 14, while on day 21, these parameters were significantly (p < 0.05) higher in group D than in the treated groups. On day 14 of CFZ administration, the alanine transaminase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP) activities of dogs in group C was significantly (p < 0.05) elevated than the control group.Conclusion: These findings suggest that CFZ, at the doses of 12.5 - 25 mg/kg, appears safe in dogs as most of the adverse effects observed are reversed following the withdrawal of the drug on day 28. However, CFZ at 50 mg/kg causes anaemia, tachycardia and bilateral paralysis of the hind limbs which did not revert to normal after one week; hence, it is not recommended for use in dogs at this dose

Evidence-based investigations into the ethnoveterinary use of Mimosa pudica L. (Fabaceae) as an anthlemintic

Purpose: To investigate the toxicity, clinical outcome and anthelmintic effects of M. pudica in vitro and in vivo.Methods: Dried leaves of M. pudica were extracted using 70 % methanol cold maceration method. Acute toxicity inquiry was evaluated using Lorke’s method. Anthelmintic effects were investigated in vitro using the egg hatch assay and in vivo using Heligmosomoides bakeri experimentally infected adult albino mice. Coprological and haematological parameters were recorded during the experiment while the serological analysis and post mortem worm burden were assessed at the conclusion of the research.Results: No mortality was recorded in oral acute toxicity test up to a dose of 5000 mg/kg. A probit-log analysis of the percentage egg hatch of the extract and albendazole gave lethal concentration 50 (LC50) values of 1.160 and -1.042, respectively. A reduction in worm count was observed in all the extracttreated groups post mortem, with the maximum extract group having the least worm count (p < 0.05). Treatment with extract resulted in improvement in the haematological parameters. Serum chemistry revealed no significant differences (p > 0.05) in alanine aminotransferase and blood urea nitrogen in all groups. However, a dose-dependent increases in the total protein and albumin was observed.Conclusion: These results show that although M. pudica has weak anthelmintic effects compared to albendazole (standard  anthelmintic), in vivo and in vitro, at the doses used in this study, nonetheless, it reduces worm burden and improves haematologic parameters, serum total protein, albumin and overall weight gain of the treated mice. Thus, increased doses may be effective in anthelmintic chemotherapy. Keywords: Mimosa pudica, Anthelmintic, Toxicity, Heligmosomoides bakeri, Ethnoveterinary medicine, Anthelminti

Molecular detection of rabies lyssaviruses from dogs in Southeastern Nigeria : evidence of transboundary transmission of rabies in West Africa

Despite being the first country to register confirmed cases of Mokola and Lagos bat lyssaviruses (two very distant lyssaviruses), knowledge gaps, particularly on the molecular epidemiology of lyssaviruses, still exist in Nigeria. A total of 278 specimens were collected from dogs in southeastern Nigeria between October 2015 and July 2016, and 23 (8.3%) of these tested positive for lyssaviruses with the direct fluorescent antibody test (DFA). The lyssaviruses were genetically characterized by amplifying the highly conserved nucleoprotein (N) gene of the rabies lyssaviruses (RABVs) of the viral genome. Phylogenetic analyses of the nucleotide sequences showed that all the RABV sequences in this study were of the Africa-2 lineage. Our results demonstrated that transboundary transmission of rabies lyssavirus is a key event, given that one of the RABV sequences (MN196576) clustered with rabies variants from neighboring Niger Republic. Furthermore, three RABVs from dogs from Anambra State clustered separately forming a novel and distinct group. Our results demonstrated that transboundary transmission of RABLVs is a key driver in the spread of rabies in West Africa. In order for the successful control of this zoonotic disease, a multinational stepwise surveillance and elimination of rabies in Africa by 2030 is probably the solution for regional elimination.The Tertiary Educational Trust Fund (TETFund) of the Nigerian government through University of Nigeria IBR and Bench Space Intervention (TETFUND/DESS/UNI/NSUKKA/RP/VOL.V) and also the ARC-OVI National Assets [P10000029] Onderstepoort Veterinary Institute, South Africa.http://www.mdpi.com/journal/virusesam2021Veterinary Tropical Disease

Anatomija orofarinksa i jezika u afričke crnobijele vrane (Corvus albus)

An understanding of the anatomy of components of the digestive tract of the African pied crow would prove useful in relation to the medical, surgical and nutritional management of these birds, especially in captivity. The present study was designed to provide basic data on the morphology of the oropharynx and tongue of the African pied crow. Our results showed that the roof of the oropharyngeal cavity was formed by a cartilaginous hard palate, whose mucous membrane exhibited many caudally directed papillae. The tongue was located in the floor of the oropharyngeal cavity. The rostral and caudal parts of the tongue were demarcated by a transverse row of caudally pointed papillae. The histology of the caudal part of the tongue revealed the presence of many mucous glands that discharge their secretions onto the dorsal surface of the tongue via ducts. Whereas the papillae may serve principally as mechanical obstacles to the involuntary return of food that has passed over them, the secretions of the glands may aid in swallowing by lubricating the caudal part of the oropharyngeal cavity and probably, the initial part of the oesophagus. It was concluded that the anatomical features of the oropharyngeal cavity and tongue of the African pied crow may be adaptations to the bird’s mode of food acquisition and feeding habits.Proučavanje anatomije probavnoga sustava afričke crnobijele vrane potrebno je radi njezina liječenja, pravilnoga načina hranidbe i kirurških zahvata što je od posebnoga značenja kad se ona drži u zatočeništvu. Ovo istraživanje provedeno je u svrhu prikupljanja temeljnih podataka o morfologiji orofarinksa i jezika afričke crnobijele vrane. Polučeni rezultati pokazali da je krov njezine orofaringealne šupljine građen od tvrdoga hrskavičnoga nepca na čijoj se sluznici nalazi mnoštvo kaudalno usmjerenih papila. Jezik je smješten na dnu orofaringealne šupljine. Rostralni i kaudalni dijelovi jezika odijeljeni su poprječnim redom kaudalno usmjerenih papila. U kaudalnom dijelu jezika nalazi se mnoštvo sluznih žlijezda koje svoje sekrete izlučuju na dorzalnu površinu jezika putem kanalića. Dok papile prvenstveno služe kao mehanička prepreka za povratak hrane, lučevine žlijezda mogu pomoći pri gutanju podmazivanjem kaudalnoga dijela orofaringealne šupljine i, vjerojatno, početnoga dijela jednjaka. Može se zaključiti da je anatomska građa orofaringealne šupljine i jezika afričke crnobijele vrane prilagođena hranidbenim navikama i načinu uzimanja hrane

Detection of lyssavirus antigen and antibody levels among apparently healthy and suspected rabid dogs in South‑Eastern Nigeria

OBJECTIVES : Domestic dogs are the main reservoir of rabies virus (RABV) infection in Nigeria, thus surveillance of rabies in dog populations is crucial in order to understand the patterns of spread of infection and ultimately devise an appropriate rabies control strategy. This study determined the presence of lyssavirus antigen in brain tissues and anti-rabies antibodies in sera of apparently healthy and suspected-rabid dogs slaughtered for human consumption at local markets in South-Eastern Nigeria. RESULTS : Our findings demonstrated that 8.3% (n = 23) of brain tissues were lyssavirus positive and 2.5% (n = 25) of sera had rabies antibody levels as percentage blocking of 70% and above correlating with a cut-off value ≥ 0.5 IU/ mL in the fluorescent antibody neutralization test. There was an inverse correlation between lyssavirus positivity and rabies antibody levels confirming that infected individuals most often do not develop virus neutralizing antibodies to the disease. The low percentage of rabies antibodies in this dog population suggests a susceptible population at high risk to RABV infection. These findings highlight a huge challenge to national rabies programs and subsequent elimination of the disease from Nigeria, considering that majority of dogs are confined to rural communal areas, where parenteral dog vaccination is not routinely undertaken.Additional file 1. Geographical location of South Eastern Nigeria and the States involved in the study. Map of the study area.The authors thank staff of National Veterinary Research Institute, Vom Plateau State, Nigeria and OIE Rabies Reference Laboratory, Onderstepoort, South Africa for laboratory and technical support. We also thank Dr. Ekene Ezenduka for assistance with the data analysis.This work was partly funded by the Tertiary Educational Trust Fund (TETFund) of the Nigerian government through University of Nigeria IBR Intervention (TETFUND/DESS/UNI/NSUKKA/RP/VOL.V) and the ARC-OVI National Assets [P10000029]. The bench work was undertaken at the Rabies Unit, Onderstepoort Veterinary Institute, South Africa. The TETFund and ARC-OVI National Assets were involved in the design of the study, TETFund funded the collection of data and analyses in Nigeria, while the ARC-OVI was responsible for the analyses of data in South Africa and manuscript writing.https://bmcresnotes.biomedcentral.comam2019Veterinary Tropical Disease

Prevalence and risk factors associated with Cryptosporidium spp. infection in local breed of dogs in Enugu State, Nigeria

Aims: Cryptosporidiosis is an important zoonotic disease of major public and veterinary concern. The disease affects humans and a variety of animal species including the domestic dog. This study aimed to determine the prevalence and risk factors associated with Cryptosporidium spp. infection in local breed of dogs from different homes and those presented at veterinary hospitals and clinics in Enugu State, Nigeria. Materials and Methods: A total of 203 fresh fecal samples were collected from domestic dogs in six local government areas in Enugu State from February 2015 to August 2015. All the samples were examined using the formol-ether sedimentation method. Fecal smears were then stained by the modified Ziehl-Neelsen technique and examined under direct light microscopy. Results: A total of 74 (36.5%) dogs were infected with Cryptosporidium spp. oocysts. There was a strong association (p0.05) between the presence of Cryptosporidium spp. oocysts and age, sex, and fecal consistency. Conclusion: The findings of this work suggest that domestic dogs in Enugu State harbor and shed Cryptosporidium spp. oocysts in the environment, especially those managed semi-intensively. Such fecal shedding is particularly so and of greater zoonotic and epidemiological importance in animals that do not show clinical signs and therefore not treated. They, therefore, pose a greater public health risk, especially to immune-compromised humans and animals. Public education on the zoonotic implication of this protozoan infection is of paramount importance in Enugu State, in particular, and Nigeria, in general, considering the closeness of dogs and man

Economic and feasibility comparison of the dRIT and DFA for decentralized rabies diagnosis in resource-limited settings: The use of Nigerian dog meat markets as a case study.

BACKGROUND:Rabies lyssavirus (RABV) is the aetiologic agent of rabies, a disease that is severely underreported in Nigeria as well as elsewhere in Africa and Asia. Despite the role that rabies diagnosis plays towards elucidating the true burden of the disease, Nigeria-a country of 180 million inhabitants-has a limited number of diagnostic facilities. In this study, we sought to investigate two of the World Organization for Animal Health (OIE)-recommended diagnostic assays for rabies-viz; the direct fluorescent antibody test (DFA) and the direct rapid immunohistochemical test (dRIT) in terms of their relative suitability in resource-limited settings. Our primary considerations were (1) the financial feasibility for implementation and (2) the diagnostic efficacy. As a case study, we used suspect rabies samples from dog meat markets in Nigeria. METHODS/PRINCIPAL FINDINGS:By developing a simple simulation framework, we suggested that the assay with the lowest cost to implement and routinely use was the dRIT assay. The costs associated with the dRIT were lower in all simulated scenarios, irrespective of the number of samples tested per year. In addition to the cost analysis, the diagnostic efficacies of the two assays were evaluated. To do this, a cohort of DFA-positive and -negative samples collected from dog meat markets in Nigeria were initially diagnosed using the DFA in Nigeria and subsequently sent to South Africa for diagnostic confirmation. In South Africa, all the specimens were re-tested with the DFA, the dRIT and a quantitative real-time polymerase chain reaction (qRT-PCR). In our investigation, discrepancies were observed between the three diagnostic assays; with the incongruent results being resolved by means of confirmatory testing using the heminested reverse transcription polymerase reaction and sequencing to confirm that they were not contamination. CONCLUSIONS/SIGNIFICANCE:The data obtained from this study suggested that the dRIT was not only an effective diagnostic assay that could be used to routinely diagnose rabies, but that the assay was also the most cost-effective option among all of the OIE recommended methods. In addition, the results of our investigation confirmed that some of the dogs slaughtered in dog markets were rabies-positive and that the markets posed a potential public health threat. Lastly, our data showed that the DFA, although regarded as the gold standard test for rabies, has some limitations-particularly at low antigen levels. Based on the results reported here and the current challenges faced in Nigeria, we believe that the dRIT assay would be the most suitable laboratory test for decentralized or confirmatory rabies diagnosis in Nigeria, given its relative speed, accuracy, cost and ease of use