Morphological and molecular characterization of Amblyomma variegatum (Acari: Ixodidae) ticks from Nigeria

The association of most tick-borne pathogens with specific tick species has made it imperative that proper identification and characterization of such tick vectors is necessary for the purpose of developing effective tick and tick-borne control strategies. This study was undertaken to identify and characterize Amblyomma species ticks collected from cattle in Plateau State, North-Central, Nigeria. They were morphologically identified using diagnostic characters. Further confirmation and characterization was done genetically using a 460bp-long partial fragment of the 16S rRNA gene amplified by polymerase chain reaction (PCR). The amplified fragment was cloned and sequenced for the phylogenetic dendogram. All the examined ticks were identified as A. variegatum which was confirmed by 16S rRNA gene sequences analysis, and phylogenetic inferences showed a 99% similarity and grouping to A. variegatum of African origin. However, the A. variegatum sequences from Nigeria were clustered into 2 groups, but formed a distinct clade from the A. variegatum sequence from Ethiopia. This study was able to conclusively identify and characterize A. variegatum ticks from the study areas by utilizing morphology and molecular genotyping based on sequencing of the 16S rRNA gene.Keywords: Amblyomma variegatum, Morphology, 16S rRNA, PCR, Sequencin

Prevalence of Cryptosporidium infection in cattle from selected commercial farms and nomadic settlements in Yola, Adamawa State

Cryptosporidium species are apicomplexan parasites commonly associated with diarrhoea in both men and animals. They are of public health importance. The study aimed to determine the occurrence of Cryptosporidium species in cattle in the Yola metropolitan area, Adamawa State, Nigeria. Four hundred and sixteen (416) faecal samples were collected from cattle in commercial farms and nomadic settlements and were analyzed using Modified Ziehl Neelsen (MZN) technique. Twenty-seven (27) positive samples were subjected to nested Polymerase Chain Reaction (PCR) for the amplification of a specific fragment of 18S rRNA gene that was used to detect Cryptosporidium spp. Seventy-three (17.5%) out of 416 samples were positive for Cryptosporidium oocysts by MZN, and 26 (96.0%) out of 27 isolated oocysts of Cryptosporidium detected by MZN were positive by PCR. Commercial farms had a higher prevalence (19.2%) of Cryptosporidium oocysts than the nomadic settlements (15.9%). Based on risk factors, there was a significant association (P<0.05) between the occurrence of Cryptosporidium oocysts and factors such as sex and faecal consistency. At the same time, age, breed, management system, animal source and drinking water source varied insignificantly (P>0.05). This study has shown the occurrence of Cryptosporidium infection in cattle in the Yola metropolis. There should be an awareness campaign among public health workers on the dangers posed by the organism to humans so that the Government would enforce control and preventive measures

Development of a Hybridized Model for Predicting the Life Span of Power Transformers

Power transformers are important equipment of the electrical switchyard whose failure leads to long hours of outage. In this research, a two-stage hybridized model for determining the lifespan of power transformers is presented by using the furan content to determine the Degree of  Polymerisation (DP) of transformer. For a ‘virgin’ transformer, the furan content was about 0.01ppm while a transformer with about 10ppm was within its end of useful life. 2-Furaldehyde (2FAL) content values of  0.01ppm and 10ppm correspond to DP values of approximately 1200 and 250, respectively. These parameters were used in developing a DP model using Jacobi and Gauss Seidel numerical analysis iterative techniques. The techniques were implemented in Matrix Laboratory 8.2 (R2013b)  environment. The second stage involved the hybridisation of the developed DP model with another rate constant model adopted from Arrhenius. This stage was also implemented in Matrix Laboratory 8.2 (R2013b)  environment. The life span of the transformer was determined by adding the service age at any point in time to the remaining lifetime at that point. A GUI of the hybridised model was developed using SIMULINK blocks. The developed model yielded a DP range of 247 ≤ DP ≤ 1184. Factors such as the hotspot temperature, activation energy and pre-exponential factor were useful for the determination of lifespan.Keywords: Degree of Polymerization, Furan Content, Life Expectancy, Power Transforme

Patency and Clinico-Haematological Pathologies Sequel to Trypanosoma brucei and Trypanosoma evansi Induced Infections in Yankasa Sheep I

Trypanosomosis remains one of the most deadly protozoan diseases that pose a significant impact on livestock health in the tropics. Sixteen (16) rams aged between 24 to 30 months and weighed between 22-25kg were acclimatized under standard animal housing  conditions. Twelve (12) of the sheep deemed fit and healthy were randomly divided into four groups (I, II, III, and IV) of three sheep each. Each sheep in groups I and II was inoculated intravenously with 2 mL containing 2 X 106 trypomastigote forms of Trypanosoma brucei and Trypanosoma evansi, respectively. While group III, each sheep received 2 mL containing 2 X 106 mixed inoculums of T. brucei and T. evansi (50% each by volume of the infective inoculums). Sheep in group IV served as the non-infected control. Post-infection animals were monitored for 14 weeks for parasitaemia, clinical signs, and haematological pathologies. The patent infection became evident in groups I, II, and III between 5-21 days post-infection with average patency of 7, 20, and 8.5 days respectively. The infection was characterized by intermittent pyrexia with a significant decrease (p< 0.001) in mean weekly packed cell volume (PCV),  haemoglobin concentration (Hb), live weight gain, plasma protein, which significantly decreased (p< 0.001) in all the infected groups. Pearson’s correlation (r) indicates a strong positive correlation (r= 0.991) between parasitaemia and pyrexia, and principal component analysis (PCA) biplot increased the predictabilities of these two indices as the major precursors in the progression of the trypanosomes pathogenesis in sheep. Keywords: Trypanosomosis; Patency; Clinico-haematological pathologies; Trypanosoma brucei; Trypanosoma evansi; Yankasa shee

Occurrence of parasite eggs and oocysts in commonly consumed vegetables collected from selected markets in Zaria, Kaduna State Nigeria

A study was conducted with the objective of determining the occurrence of parasite eggs and oocysts in washed and unwashed vegetables sold in some selected markets in Zaria, Kaduna State. Cabbage (Brassica oleracea), Tomato (Lycopersicon esculentum), Lettuce (Lactuca sativa), Carrot (Daucus carota) and Spinach (Spinacea oleracea) were collected based on convenient sampling from 5 markets. Three hundred grams of each vegetable was purchased every week in the morning hours from each of the selected markets during the rainy and dry seasons. Floatation technique was used for processing of the vegetable samples. Unwashed vegetables (269) had more parasite eggs and oocysts than washed vegetables (209). Spinach (52.50%) had the highest contamination, followed by carrot (48.75%), cabbage (42.50%), lettuce (40.0%) and tomatoes (28.75%). There was a significant (p < 0.05) association between the occurrence of parasite eggs and oocysts and the washing of vegetables. Among the unwashed vegetables, lettuce was highly contaminated (58.75%) with parasite eggs and oocysts, followed by spinach (55.0%), carrot (55.0%), tomatoes (50.0%) and cabbage (39.75%). There was, however, no significant (p > 0.05) association between the occurrence of parasite eggs and oocysts and the unwashed vegetables. Among the different markets, vegetables purchased from Dan Magaji market (51.25%) were highly contaminated, followed by Tudun Wada (49.38%), Sabongari (48.75%), Zaria city (48.75%) and Samaru market (41.88%).There was, however, no significant (p > 0.05) association between the occurrence of parasite eggs and oocysts on vegetables and the markets where the vegetables were purchased. The study showed that eggs and oocysts of various parasites mainly of human and animal faecal origin were present on vegetables marketed for human consumption even after washing. Therefore, people should properly wash their vegetables before consumption and indiscriminate defecation should be discouraged to prevent contamination and improve hygienic conditions.Keywords: Eggs, Oocyst, Market, Parasite, Vegetable, Zari

In vitro release from antibiotic-loaded silicone hydrogel contact lenses for the treatment of ocular bacterial infections

Background: Effective treatment of corneal infections require frequent eye drop instillations, unfortunately, non-compliance is a challenge.Objectives: In this study, the effectiveness of antibiotic-loaded contact lens as a prolonged release device in the treatment of corneal bacterial infection is investigated.Materials and Method: Ofloxacin (OFL) and Chloramphenicol sodium succinate (CPL) were loaded onto silicone hydrogel contact lenses (CLs) via soaking method. Drug release, effect on clarity of the lenses at different concentrations and ability to inhibit growth of corneal ulcer causative bacteria were investigated.Results: Drug release from the lenses was directly proportional to the amount of drug loaded and the lenses at the different loading concentrations showed transmittance of 95 to 97%. The Air Optix® lenses showed higher release of drug compared to Acuvue Oasys® lenses (p < 0.05). The difference in drug release was significant at p < 0.05. The microbiological study showed zones of inhibition in Mueller Hinton agar seeded with Pseudomonas aeruginosa and Staphylococcus aureus.Conclusion: This study shows that contact lenses can be used to control drug delivery to the eye and is a probable alternative ocular delivery technique in the treatment or prevention of corneal infections.Keywords: Antibiotics; prolonged release; contact lens; corneal infection

Diseases as Impediments to Livestock Production and Wildlife Conservation Goals

Disease outbreaks, epidemics or pandemics have been of importance for human and animal health worldwide and sparked enormous public interest. These outbreaks might be caused by known endemic pathogens or by emerging or re-emerging pathogens. Wildlife are the major reservoirs and responsible for most of these outbreaks. They play significant role in the transmission of several livestock diseases and pathogen spill-over may occur in complex socio-ecological systems at the wildlife-domestic animal interface which have been seldom studied. Interspecific pathogen spill-over at the wildlife-livestock interface have been of growing concern in the scientific community over the past years due to their impact on wildlife, livestock and human health. In this section the epidemiology of some viral infections (Foot and Mouth Disease and rabies), bacterial infections (Tuberculosis and brucellosis) and parasites (haemo and endo-parasites) at the wildlife-livestock interface and potential impacts to livestock production and conservation goal is described

Occurrence and factors associated with faecal shedding of Cryptosporidium oocysts in small ruminants in Potiskum local government area, Yobe State, Nigeria

Cryptosporidium is an enteric protozoan pathogen associated with neonatal diarrhoea and mortality in small ruminants. Faecal samples of two hundred small ruminants were examined for Cryptosporidium oocysts using formol-ether concentration and modified Ziehl-Neelsen staining technique. Fifty seven (28.5%) out of the 200 faecal samples examined were positive for Cryptosporidium oocysts. The occurrence was higher in sheep (33.0%) than goats (24.0%), in male (32.8%) than female (26.6%), in those with loose/watery faeces (74.4%) than those with well-formed faeces (17.4%), in those between age 4-6 months (39.2%) than 0-3 months (22.2%) and those within 7 months and above (21.1%), in those that drank borehole water (28.7%) than those that drank well/stream water (20.0%), in those raised under semi-intensive/extensive (29.9%) than those under intensive system (21.1%). There was significant association between the occurrence of Cryptosporidium oocysts and age of small ruminants (OR = 2.368, 95% CI on OR: 1.251 < OR < 4.484). On the other hand, there were no significant associations between the occurrence of Cryptosporidium oocysts and sex, breed, faecal consistencies, source of water and management practices of small ruminants (P > 0.05). The species of Cryptosporidium infecting small ruminants identified in this study were C. parvum (50.9%), C. ryanae (26.3%), C. xiaoi (12.3%), C. bovis (8.8%) and C. andersonii (1.8%). The high prevalence of C. parvum observed in this study is of public health importance because of it zoonotic nature. This study shows that age influence the occurrence of Cryptosporidium oocysts and C. parvum is the predominant species in small ruminants in Potiskum, Yobe State.Keywords: Cryptosporidium, Factors, Occurrence, Potiskum, Small ruminant

Clinicopathological and Microscopic Features of Trypanosoma brucei and Trypanosoma evansi Induced Infections in Sheep II

The present study elucidates further on clinical, gross, and microscopic pathologies induced by single or mixed infections with  Trypanosoma evansi and Trypanosoma brucei in sheep. Briefly, the experimental animals were divided into four groups of three  animals each. Animals in each group were either infected with T. brucei, T. evansi, mixed (T. brucei and T. evansi), or noninfected. Animals were observed for clinical, gross, and microscopic pathologies for 98 days (14 weeks). The clinical pathologies observed included loss of body condition, pale ocular mucus membrane, rough hair coat, scrotal oedema, scrotal degeneration, emaciation, and death. At necropsy, macroscopic or gross lesions included very pale and anaemic carcass composition, congested and pneumonic lungs with severe haemorrhages, serous atrophy of intestinal and body fats, lymphadenopathy, splenomegaly, and hepatomegaly. Microscopic lesions observed in the testes, spleen, liver, lungs, lymphoid, heart, and brain tissues of infected sheep were varied and included swollen kidney with renal tubular degeneration, the proliferation of lymphocytes at the germinal centers of the spleen, degeneration of the bronchioles, severe testicular degeneration with a reduction in the number of spermatogenic cell layers,  degenerated Leydig and Sertoli cells with loss of sperm reserves in the seminiferous lumen, congested liver with sinusoidal spaces and the proliferation of monocytes and lymphocytes. The results indicate that trypanosomosis due to experimental T. brucei, T. evansi, or mixed infections may be an important cause of various grades of tissue and organ pathologies in sheep in trypanosome-endemic areas. Keywords: Trypanosomosis; Clinico-pathological and microscopic features; Trypanosoma brucei; Trypanosoma evansi; Mixed  infections; Shee

Serological assay for Trichinella antibodies in slaughtered pigs and predisposing factors to trichinellosis in backyard piggeries in Kaduna Metropolis, Nigeria

Trichinellosis is a cosmopolitan zoonotic disease that affects a large array of mammals, birds and reptiles caused by the eating of raw or undercooked pork containing Trichinella larvae. In this study, 200 pigs slaughtered at abattoirs and slaughter slabs within Kaduna Metropolis were  screened for antibodies to Trichinella excretory-secretory (E/S) antigen using Enzyme-linked Immunosorbent Assay (ELISA). An overall prevalence rate of 16% was established. Age of the pigs revealed an association with trichinellosis (p-value=0.001) with juvenile and adult pigs recording prevalence rates of 5% and 11% respectively. Sex of the animals showed no significant association with trichinellosis but the females had a higher prevalence of 9.5% compared to the 6.5% of the males who had a greater odds (O=1.083) compared to the females (O=0.950). The farm management practices: intensive (1%), semi-intensive (2.5%) and extensive (12.5%) recorded a significant relationship with trichinellosis (p-value=0.001). Sources of the pigs whether markets, backyard farms or inheritance was significantly associated with trichinellosis (p-value=0.00) with backyard farm having the highest prevalence of 7%. Poor rodents control program, presence of snakes around and within piggery, feeding of pigs with dead animals and leftovers, lack of knowledge of pork-borne diseases, allowing pigs to scavenge and interaction of the pigs with stray pigs were very important predisposing factors to trichinellosis in pig farms established from this research. The result of this work therefore, is ofpublic health importance because meat and meat products are considered very important sources of daily protein in-take in Kaduna Metropolis, Nigeria. Keywords: Antibodies; ELISA; Kaduna Metropolis; Nigeria; trichinella; trichinellosis; predisposing factors; farm management