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Serogrouping and resistance gene detection in avian pathogenic E.coli isolated from broiler chickens
2019
Asmaa Abd Elatiff | Azza A. El-Sawah | Mohamed M. Amer | Al-Hussein M. Dahshan | Hala Salam | Salama A.S.Shany
E coli infection in poultry is one of the principle causes of mortality and morbidity in chickens and turkeys resulting in retardation of growth and decreased feed conversion rate . The most common form of collibacillosis is characterized as an initial respiratory infection (air sacculitis) followed by generalized septicemia, perihepatitis and pericarditis. The present study aimed to identify the bacteria associated with pericarditis , airsacculitis and perihapatitis in Egyptian broiler chickens. A total 300 samples of diseased and dead broilers from 3-6 weeks age were collected. The isolated bacteria included E. coli, Klebsiella spp., Shigella spp. And Enterobacter spp. Sero-grouping of the isolated E. coli strains revealed O125, O158, O55,O129, O20 , O6 , O8 , O27, O115, O142 and un-typed strains with prevalence of 16%, 12%, 8%, 8%, 8% , 8% , 8% , 8% ,4%,4% and 16% respectively. The majority of E coli isolates were sensitive to colistin sulphate (38%) and Norofloxacin (38%) followed by ciprofloxacin (19%), cefotaxim (19%) and Ofloxacin (19%). On the other hand, E coli were resistant (100%)to amoxicillin, clindamycin , Erythromycin and streptomycin. PCR analysis for antibiotic resistance genes of E coli detected that 12 serogroups isolates were positive using the specific primers for Aada2 , BlaCTX and TetA(A) genes. The current study demonstrated the high prevalence of E. coli indeed broilers suffered from pericarditis , perihepatitis and airsacculitis . Measures are needed to control E. coli contamination in poultry farms to reduce economic losses caused by infection of E.coli.
Показать больше [+] Меньше [-]Factors affecting the immunogenicity of E. coli O78 vaccine in chickens
2019
El-Seedy, F.R. | Aml Mokhtar | Eman Khalifa | Sara Sayed
Bacterial disease still has serious problem in the intensive poultry production. In the recent years, particular concern has been raised by high incidence of poultry infections by E. coli. Analyses of antibacterial properties of essential oils have been carried out by range of researches. This experiment aimed to study the effect of immunomodulators on the immunogenicity of vaccine E. coli O78. In this study 250 broiler chickens were used. They were divided into 5 separated groups all groups vaccinated with E. coli O78 cebel coarse spray vaccine, except control group, 2 groups treated with immunomodulators, 3 groups challenged with untyped E. coli strain, all chickens housed in separated anavar. First group was control, 2nd group was vaccinated only, 3rd group was vaccinated and challenged, 4th group was vaccinated and received immunomodulators and 5th group was vaccinated, received immunomodulators and challenged. All chickens were observed daily food consumption, weight gained mortality rate, lesion, bioavailability, and weekly collected blood samples from 2-5 birds. The results were summarized as follows; immunomodulators have positive effect on B.W.G, decreased mortality and morbidity rate. The challenge enhanced the effect of E. coli O78 vaccine and there was marked improvement in bioavailability, B.W.G and immune defense against bacterial and respiratory diseases. Also, immunomodulators increased immunogenicity against bacterial disease through enhancing immune response system, and had synergistic effect with vaccination against E. coli.
Показать больше [+] Меньше [-]Effect of virgin olive oil supplementation on lipid profile and oxidative status in rats
2019
Farahat A. A. | Sawiress F. A | Aghwider A. A.
The aim of the present study is to investigate the effect of virgin olive oil on some blood parameters in male Albino rats supplemented with normal diet. thirty male Sprague Dawley rats, (90-110 g), were used in the present study, and were divided into three groups (10 in each), 1st group (control), received basal diet and supplemented with 1ml saline. 2nd and 3rd groups received basal diet, and supplemented daily with 1ml/100 gm B.W and 2ml/100 gm B.W of virgin olive oil (VOO), respectively for 4 weeks. Blood samples were collected weekly from all rats. Serum samples was obtained for assay of lipid profile levels and hepatic lipid peroxidation (MDA) enzyme. Blood lysate was used for antioxidant enzymes activities SOD, GPx and CAT.
Показать больше [+] Меньше [-]Safety and immunogenicity of Rift Valley fever MP-12 and arMP-12ΔNSm21/384 vaccine candidates in goats (Capra aegagrus hircus) from Tanzania
2019
Nyundo, Salama(Sokoine University of Agriculture Department of Microbiology, Parasitology and Biotechnology) | Adamson, Ester(Sokoine University of Agriculture Department of Microbiology, Parasitology and Biotechnology) | Rowland, Jessica(Sokoine University of Agriculture Department of Microbiology, Parasitology and Biotechnology) | Palermo, Pedro M.(University of Texas at El Paso Department of Biological Sciences) | Matiko, Mirende(Sokoine University of Agriculture Department of Microbiology, Parasitology and Biotechnology) | Bettinger, George E.(University of Texas at El Paso Department of Biological Sciences) | Wambura, Philemon(Sokoine University of Agriculture Department of Microbiology, Parasitology and Biotechnology) | Morrill, John C.(Orion Research and Management Services) | Watts, Douglas(University of Texas at El Paso Department of Biological Sciences)
Vaccination of domestic ruminants is considered to be an effective strategy for protecting these animals against Rift Valley fever (RVF), but available vaccines have limitations. Therefore, the aim of this study was to determine the safety and immunogenicity of RVF virus (RVFV) mutagenesis passage 12 (MP-12) and arMP-12ΔNSm21/384 vaccine candidates in goats (Capra aegagrus hircus) in Tanzania. Goats were vaccinated intramuscularly with RVFV MP-12 or arMP-12ΔNSm21/384, and then on Day 87 post-vaccination (PV) all animals were revaccinated using the RVFV MP-12 vaccine candidate. Serum samples were collected from the animals before and after vaccination at various intervals to test for RVFV using a Vero cell culture assay and reverse transcription polymerase chain reaction and for RVFV-neutralising antibody using a plaque reduction neutralisation assay. Serum samples collected before vaccination on Days -14 and 0, and on Days 3, 4 and 5 PV were negative for RVFV and neutralising antibody. All animals remained healthy, and viremia was not detected in any of the animals. Rift Valley fever virus antibody was first detected on Day 5 PV at a 1:10 dilution in five of five animals vaccinated with the MP-12 vaccine and in five of eight animals vaccinated with arMP-12ΔNSm21/384. Titres then increased and were sustained at 1:40 to 1:640 through to Day 87 PV. All animals that were revaccinated on Day 87 PV with MP-12 developed antibody titres ranging from 1:160 to as high as 1:10 240 on Days 14 and 21 PV. Although the antibody titres for goats vaccinated with RVF MP-12 were slightly higher than titres elicited by the arMP-12ΔNSm21/384 vaccine, these findings demonstrated that both vaccines are promising candidates for the prevention of RVF among Tansanian goats.
Показать больше [+] Меньше [-]Peste des petits ruminants in Africa: Meta-analysis of the virus isolation in molecular epidemiology studies
2019
Mantip, Samuel E.(University of Abomey-Calavi Department of Animal Health and Production ,National Veterinary Research Institute Viral Research Division) | Shamaki, David(National Veterinary Research Institute Viral Research Division) | Farougou, Souabou(University of Abomey-Calavi Department of Animal Health and Production)
Peste des petits ruminant (PPR) is a highly contagious, infectious viral disease of small ruminant species which is caused by the peste des petits ruminants virus (PPRV), the prototype member of the Morbillivirus genus in the Paramyxoviridae family. Peste des petits ruminant was first described in West Africa, where it has probably been endemic in sheep and goats since the emergence of the rinderpest pandemic and was always misdiagnosed with rinderpest in sheep and goats. Since its discovery PPR has had a major impact on sheep and goat breeders in Africa and has therefore been a key focus of research at the veterinary research institutes and university faculties of veterinary medicine in Africa. Several key discoveries were made at these institutions, including the isolation and propagation of African PPR virus isolates, notable amongst which was the Nigerian PPRV 75/1 that was used in the scientific study to understand the taxonomy, molecular dynamics, lineage differentiation of PPRV and the development of vaccine seeds for immunisation against PPR. African sheep and goat breeds including camels and wild ruminants are frequently infected, manifesting clinical signs of the disease, whereas cattle and pigs are asymptomatic but can seroconvert for PPR. The immunisation of susceptible sheep and goats remains the most effective and practical control measure against PPR. To carry out PPR vaccination in tropical African countries with a very high temperature, a thermostable vaccine using the rinderpest lyophilisation method to the attenuated Nigeria 75/1 PPR vaccine strain has been developed, which will greatly facilitate the delivery of vaccination in the control, prevention and global eradication of PPR. Apart from vaccination, other important questions that will contribute towards the control and prevention of PPR need to be answered, for example, to identify the period when a susceptible naïve animal becomes infectious when in contact with an infected animal and when an infectious animal becomes contagious.
Показать больше [+] Меньше [-]Prevalence of gastrointestinal helminths and parasites in smallholder pigs reared in the central Free State Province
2019
Nwafor, Ifeoma C.(Central University of Technology Faculty of Health and Environmental Sciences Department of Agriculture) | Roberts, Hester(Central University of Technology Faculty of Health and Environmental Sciences Department of Life Sciences) | Fourie, Pieter(Central University of Technology Faculty of Health and Environmental Sciences Department of Agriculture)
Pigs are kept by farmers as a source of livelihood and food. Unfortunately, helminthiasis and other internal parasites are major setbacks to profitable pig production in Africa. There is a lack of information on the prevalence and intensity of gastrointestinal helminths and parasites plaguing resource-poor pig farmers in the Free State. Knowledge of these endemic parasites can be used as baseline data to help design future intervention plans. The aim of this study was to identify and quantify the types of gastrointestinal helminths and parasites prevalent in smallholder pigs reared in the central Free State Province. Faecal samples were randomly collected from 77 pigs and parasitologically analysed. Quantification was done using the McMaster counting technique. Farming system, age, gender and health status were the risk factors considered. The study was conducted between January and March 2016. Overall, results showed that 61 samples (79.2%) tested positive for one or more gastrointestinal parasites, which were observed as single or mixed infections. Amongst the positive samples, 44.5% were infected with Ascaris suum, 50.6% with Trichuris suis, 26.0% and 72.7% were infected with Oesophagostomum dentatum and coccidia, respectively. There were significant differences (p < 0.05) between the rate of infection in the intensive and semi-intensive systems and between the dewormed and non-dewormed pigs. Piglets and female pigs recorded a higher prevalence in their categories. Pigs excreted mostly low (eggs per gram [EPG] ≤ 100) to moderate (EPG > 100 < 500) levels of helminth eggs. It is concluded that different species of gastrointestinal parasites are present in most pigs reared by smallholder farmers in this study area.
Показать больше [+] Меньше [-]The effects of extraction techniques and quantitative determination of oxalates in Nerium oleander and feeds
2019
Kgosana, Kedibone G.(Agricultural Research Council Toxicology and Ethnoveterinary Medicine)
Shrubs represent the most affordable and accessible form of feed that livestock can rely on to acquire both essential and non-essential elements of life. In addition to their inherent toxins, they contain endogenous substances commonly referred to as 'antinutritive factors' (ANFs) that often interfere with the utilisation of nutrients. Their abundance may lead to severe clinical trauma. Hence, the objective of the study was to investigate the effects of different extraction techniques on Nerium oleander L. and animal feeds as well as to quantify oxalates. Organic (hexane, acetone and methanol) sequential and aqueous (infusion and decoction) extractions were explored. Qualitative and quantitative analyses were conducted to determine the presence of various phytochemicals and oxalate contents as putative ANFs, respectively. The results showed higher extraction yields of 22.6% and 43.1% in the decoction and infusion of N. oleander, respectively. The quantification methods were validated for linearity, accuracy and precision. Oxalate contents of 6.76 ± 0.245 (0.65%) mg/g and 5.74 ± 0.236 mg/g dry weight (0.55%) were obtained in N. oleander and feeds, respectively. This difference was statistically significant with p < 0.05. Percentage recoveries of 98.5 (percent relative standard deviation [% RSD] = 2.3), 85.7 (% RSD = 1.03) and 80.3 (% RSD = 1.22) at 76%, 95% and 112% fortifications were obtained, respectively. Relative standard deviation for precision was 0.99% and 1.13% at 0.33 mg and 0.39 mg fortifications, respectively, while reproducibility showed 2.21% RSD. Therefore, these methods can be used to provide a valuable basis for qualitative determination of ANFs, particularly in shrub foliage.
Показать больше [+] Меньше [-]African animal trypanosomosis (nagana) in northern KwaZulu-Natal, South Africa: Strategic treatment of cattle on a farm in endemic area
2019
Latif, Abdalla A.(University of KwaZulu-Natal School of Life Sciences) | Ntantiso, Lundi(Makhathini Research Station) | de Beer, Chantel(Agricultural Research Council-Onderstepoort Veterinary Research)
African animal trypanosomosis (AAT) is caused by several species of the genus Trypanosoma, a parasitic protozoan infecting domestic and wild animals. One of the major effects of infection with pathogenic trypanosome is anaemia. Currently, the control policies for tsetse and trypanosomosis are less effective in South Africa. The only response was to block treat all infected herds and change the dip chemical to one which controls tsetse flies during severe outbreaks. This policy proved to be less effective as demonstrated by the current high level of trypanosome infections in cattle. Our objective was to study the impacts of AAT (nagana) on animal productivity by monitoring the health of cattle herds kept in tsetse and trypanosomosis endemic areas before and after an intervention that reduces the incidence of the disease. The study was conducted on a farm in northern KwaZulu-Natal which kept a commercial cattle herd. There was no history of any cattle treatment for trypanosome. All cattle were generally in poor health condition at the start of the study though the herd received regular anthelminthic treatment. A treatment strategy using two drugs, homidium bromide (ethidium) and homidium chloride (novidium), was implemented. Cattle were monitored regularly for 13 months for herd trypanosomosis prevalence (HP), herd average packed cell volume (H-PCV) and the percentage of the herd that was anaemic (HA). A total of six odour-baited H-traps were deployed where cattle grazed from January 2006 to August 2007 to monitor the tsetse population. Glossina brevipalpis Newstead and Glossina austeni Newstead were collected continuously for the entire study period. High trypanosomes HP (44%), low average H-PCV (29.5) and HA (24%) were rerecorded in the baseline survey. All cattle in the herd received their first treatment with ethidium bromide. Regular monthly sampling of cattle for the next 142 days showed a decline in HP of 2.2% - 2.8%. However, an HP of 20% was recorded by day 220 and the herd received the second treatment using novidium chloride. The HP dropped to 0.0% and HA to 0.0% by day 116 after the second treatment. The cow group was treated again by day 160 when the HP and HA were 27.3% and 11%, respectively. The same strategy was applied to the other two groups of weaners and the calves at the time when their HP reached 20%. Ethidium and novidium treatment protected cattle, that were under continuous tsetse and trypanosomosis challenge, for up to 6 months. Two to three treatments per year may be sufficient for extended protection. However, this strategy would need to be included into an integrated pest management approach combining vector control for it to be sustainable.
Показать больше [+] Меньше [-]Molecular detection and genetic characterisation of pathogenic Theileria, Anaplasma and Ehrlichia species among apparently healthy sheep in central and western Kenya
2019
Ringo, Aaron E.(Obihiro University of Agriculture and Veterinary Medicine National Research Center for Protozoan Diseases) | Aboge, Gabriel O.(University of Nairobi Faculty of Veterinary Medicine Department of Public Health, Pharmacology and Toxicology) | Moumouni, Paul F. Adjou(Obihiro University of Agriculture and Veterinary Medicine National Research Center for Protozoan Diseases) | Lee, Seung Hun(Obihiro University of Agriculture and Veterinary Medicine National Research Center for Protozoan Diseases) | Jirapattharasate, Charoonluk(Mahidol University Faculty of Veterinary Science Department of Pre-clinic and Applied Animal Science) | Liu, Mingming(Obihiro University of Agriculture and Veterinary Medicine National Research Center for Protozoan Diseases) | Gao, Yang(Obihiro University of Agriculture and Veterinary Medicine National Research Center for Protozoan Diseases) | Guo, Huanping(Obihiro University of Agriculture and Veterinary Medicine National Research Center for Protozoan Diseases) | Zheng, Weiqing(Nanchang Center for Disease Control and Prevention Department of Disinfection and Vector Control) | Efstratiou, Artemis(Obihiro University of Agriculture and Veterinary Medicine National Research Center for Protozoan Diseases) | Galon, Eloiza M.(Obihiro University of Agriculture and Veterinary Medicine National Research Center for Protozoan Diseases) | Li, Jixu(Obihiro University of Agriculture and Veterinary Medicine National Research Center for Protozoan Diseases) | Thekisoe, Oriel(North-West University Unit for Environmental Sciences and Management) | Inoue, Noboru(Obihiro University of Agriculture and Veterinary Medicine) | Suzuki, Hiroshi(Obihiro University of Agriculture and Veterinary Medicine National Research Center for Protozoan Diseases) | Xuan, Xuenan(Obihiro University of Agriculture and Veterinary Medicine National Research Center for Protozoan Diseases)
Tick-borne diseases (TBDs) caused by Theileria, Babesia, Anaplasma and Ehrlichia species are common in tropical and subtropical regions. In this study, we investigated the presence and genetic diversity of Theileria spp., Anaplasma ovis, B. ovis, E. ruminantium and Anaplasma spp. in sheep from the Machakos and Homa Bay counties of Kenya. In order to improve the diagnosis and control of ovine TBDs, a total of 76 blood samples from apparently healthy sheep were screened using a polymerase chain reaction (PCR). The assays were conducted using primers based on Theileria spp. 18S rRNA, Anaplasma ovis Major surface protein-4 (AoMSP4), B. ovis 18S rRNA, E. ruminantium pCS20 and Anaplasma spp. 16S rRNA. The overall infection rates for Theileria spp., A. ovis, E. ruminantium and Anaplasma spp. were 39/76 (51.3%), 26/76 (34.2%), 6/76 (7.9%) and 31/76 (40.8%), respectively. The overall co-infection was 47/76 (61.8%). All Theileria spp. positive samples were confirmed to be of Theileria ovis on sequencing. A phylogenetic analysis of the 18S rRNA gene sequences of T. ovis revealed that all isolates of this study clustered with T. ovis sequences extracted from the GenBank suggesting this gene is highly conserved. E. ruminantium pCS20 sequences were in the same clade on the phylogenetic tree. However, three AoMSP4 sequences from this study appeared in the same clade, while one sequence formed a separate branch revealing genetic divergence. The 16S rRNA sequencing revealed uncharacterised Anaplasma spp. and A. ovis. The phylogenetic analyses of the uncharacterised Anaplasma spp. revealed that the two sequences from this study appear in an independent clade from other sequences extracted from the GenBank. This study provides important information regarding the occurrence of tick-borne pathogens and their degree of genetic diversity among sheep in Kenya, which is useful for the diagnosis and control of TBDs.
Показать больше [+] Меньше [-]Seasonal occurrence of metazoan parasites in Tigerfish, Hydrocynus vittatus Castelnau, 1861 (Characiformes: Alestidae) from Sanyati Basin, Lake Kariba, Zimbabwe
2019
Mabika, Nyasha(University of Johannesburg Department of Zoology ,University of Zimbabwe Department of Anatomy) | Barson, Maxwell(University of Zimbabwe Department of Biological Sciences) | van Dyk, Cobus(University of Johannesburg Department of Zoology) | Avenant-Oldewage, Annemariè(University of Johannesburg Department of Zoology)
Lake Kariba is a tropical lake with slight variations in seasonal temperature. Temperature is an important physical variable in the biology of both fish and their parasites. Currently, there is no information on the seasonal occurrence of fish parasites in Lake Kariba. The objective of this study was to investigate the seasonal occurrence of metazoan parasites in Hydrocynus vittatus in Lake Kariba, Zimbabwe. Twenty fish specimens were collected by seine netting per season between October 2014 and July 2015 in the Sanyati Basin, Lake Kariba, and examined for metazoan parasites. Mean water temperatures ranged from 24.1 °C to 31.2 °C with slight variations between the seasons. Metazoan parasites consisting of Monogenea (Annulotrema pikei, Annulotrema pseudonili, Annulotrema bracteatum), Nematoda (Contracaecum larvae), Copepoda (Lamproglena hemprichii), Cestoda (larval cestodes, Ichthybothrium sp.) and Pentastomida (pentastomid larvae) were recorded. Larval cestodes were recorded in autumn and spring, while pentastome larvae were recorded in summer and spring. The Ichthybothrium sp. was recorded once in winter. Annulotrema pikei and A. pseudonili were observed on the gills and A. bracteatum on both the gills and the skin. Contracaecum larvae, L. hemprichii and A. bracteatum (from the skin) were recorded in all the seasons, with slight variations in prevalence, mean abundance and mean intensity. However, these variations were not statistically significant (analysis of variance or ANOVA, p > 0.05). The slight variations in occurrence of the parasites were probably because of the thermal stability of the lake where variation in temperature was small between seasons. Both A. bracteatum and Contracaecum larvae were aggregated on the fish host, whereas L. hemprichii exhibited a random distribution. Parasite diversity was at its highest during winter.
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