44 research outputs found
Synchronous Flyback Converter Coupled with Fuzzy Logic Control Efficiently Controls a Serially Connected VRLA Battery String
AbstractThis paper presents a high efficiency charge equalization system for balancing the energy in a serially connected, valveregulated, lead acid battery string using a synchronous flyback converter. Each flyback converter was coupled through a DC-link bus in order to increase the overall energy transfer efficiency of the system and to eliminate the problem of unbalanced charging of the batteries. To ensure that the charge equalization system operated smoothly and safely charged the batteries, a fuzzy logic controller was used in the control section of the system. The validity of this approach was confirmed by computer simulation and by experimentation. The efficiency of this synchronous flyback converter was 78.9 percent, better by approximately 1.07 percentthan the conventional flyback converter
Detection of Salmonella in Poultry Using Conventional Culture Methods and Polymerase Chain Reaction Technique
A study was carried out to evaluate three culture media and PCR for the detection of Salmonella spp. to improve Salmonella monitoring program. A total of 109 samples were collected from two farms. Sixty four samples were collected from farm A. These included 16 cloacal swabs collected from broilers before slaughtering, 18 intestinal swabs and 20
caecal swabs collected from broilers after evisceration, and 10 cloacal swabs collected from village chickens. Forty five samples were collected from farm B, which included 15 cloacal swabs from each of village chickens, turkeys, and guinea fowls. Samples were pre-enriched in BPW and investigated by plating them on XLT4 agar after enrichment in selenite cystine broth, BPLS agar after enrichment in Rappaport-Vasilliadis broth, and DIASALM directly after
pre-enric hment in BPW. Suspected positive colonies were confirmed biochemically and serologically. DIASALM and BPLS agar were comparatively evaluated against XLT4 agar as the "gold standard" using Kappa statistic to determine the level of agreement between them. A total of 27 (24.77%) Salmonella were detected from the 109 samples. Isolation rates for XLT4, DIASALM, and BPLS were 20.20% (22 out of 109), 17.43% (19 out of 109), and 13.8% (15 out of 109), respectively. The sensitivity and agreement (Kappa statistic) with the "gold standard" for each evaluated detection method were: 70.4% and 0.69 (substantial) for DIASALM and 55.56% and 0.58 (mode rate) for BPLS. For the detection of Salmonella spp. by PCR, bacterial chromosomal
DNA was extracted by boiling. Amplicons (429 bp) and (284 bp) derived from primers to the genomic random fragment (primers ST11 and ST15) and invA genes (primers 139 and 141) respectively, were confirmed as Salmonella specific on ethidium bromide-stained agarose gels. Using PCR assay Salmonella was detected 24% (13 out of 54) and 13% (7 out of 54) in broilers in farm A using primers ST11-ST15 and 139-141, respectively. Poultry species in farm B were negative for Salmonella by PCR. A specific primer was used for the detection of Salmonella enteritidis. None of Salmonella detected was Salmonella enteritidis. This study concluded that XLT4 agar is the most sensitive medium and is very specific for the isolation of Salmonella from chicken feces. DIASALM is a good medium for the isolation of Salmonella. The inability of PCR to successfully detect Salmonella specific products from all the samples that were positive for isolation is not clear. However, this would
be partly explained by the presence of inhibitor factors in the DNA preparations. In addition, the primer set ST11-ST15 used in this study has not before been tested on cloacal swabs and fecal samples from poultry. Perhaps, with improved DNA extraction method may overcome the inhibitory problem and also low yield of DNA. PCR should be used
together with cultivation for the detection of Salmonella especially when the serovar is to be determined
Chlorpyrifos chronic toxicity in broilers and effect of vitamin C
An experiment was conducted to study chlorpyrifos chronic toxicity in broilers and the protective effect of vitamin C. Oral administration of 0.8 mg/kg body weight (bw) (1/50 LD50) chlorpyrifos (Radar®), produced mild diarrhea and gross lesions comprised of paleness, flaccid consistency and slightly enlargement of liver. Histopathologically, chlorpyrifos produced degenerative changes in various organs. Oral administration of 100 mg/kg bw vitamin C partially ameliorated the degenerative changes in kidney and heart. There was insignificant alteration in biochemical and haematological profiles. It is concluded that supplementation of vitamin C reduced the severity of lesions induced by chronic chlorpyrifos toxicity in broilers
Surveillance of the spread of avian influenza virus type A in live bird markets in Tripoli, Libya, and determination of the associated risk factors
Background and Aim: Studies on avian influenza virus (AIV) in Libya are few and limited. This study aimed to determine the presence of AIV in live bird markets (LBMs) in Tripoli and determine the risk factors associated with AIV spread.
Materials and Methods: In total, 269 cloacal swabs were randomly collected from different bird species in 9 LBMs located in Tripoli and its surrounding regions. The target species were ducks, geese, local chickens, Australian chickens, Brahma chickens, turkeys, pigeons, quails, peacock broiler chicks, and pet birds. Total RNA was extracted from the swab samples and used for real-time polymerase chain reaction to detect AIV type A.
Results: Of the 269 samples, 28 (10.41% of total samples) were positive for AIV type A. The LBMs with positive samples were Souq Aljumaa, Souq Alkhamees, Souq Althulatha, and Souq Tajoura. The highest percentage (35.71%) of AIV was recorded in Souq Aljumaa. Positive results for AIV type A were obtained primarily in three species of birds: Ducks (14/65; highest percentage: 21.5%), local chickens (12/98; 12.24%), and geese (2/28; 7.14%). Furthermore, the following three risk factors associated with the spread of AIV type A were identified: Time spent by breeders/vendors at the market (odds ratio [OR] = 11.181; 95% confidence interval [CI] = 3.827–32.669), methods used for disposing dead birds (OR = 2.356; 95% CI = 1.005–5.521), and last visited LBM (OR = 0.740; 95% CI = 0.580–0.944). Restricting the movement of poultry vendors from one market to another may protect against AIV spread.
Conclusion: The findings of this study indicate the high risk of AIV spread in LBMs and highlight the need for continuous surveillance of LBMs across the country
Ovine paratuberculosis: a confirmed case of Johne's disease in Libya
Paratuberculosis (Johne's disease) was suspected in a herd of approximately 300 sheep after weight loss and scouring had increased in adult animals despite repeated treatment with anthelmintics, antibiotics, multivitamins and minerals. The herd is located near Tarhouna city. Herd history revealed that a total of 60 ewes showed clinical symptoms and deaths during the last two years. The last case that we attended was submitted to the National Center of Animal Health (NCAH) for a detailed laboratory examination. Gross pathological and histological examination of tissue samples revealed results that were highly comparable with Johne's disease. A definitive diagnosis was made only by histopathological identification of Mycobacterium paratuberculosis in the intestines using Ziehl-Neelsen stain. This is the first documented case of M. paratuberculosis in sheep in Libya
Molecular detection and chracterization of infectious bronchitis virus from Libya.
Infectious bronchitis virus (IBV) is a very dynamic
and evolving virus, causing major economic losses to the global poultry industry. Recently, the Libyan poultry industry faced severe outbreak of respiratory distress associated with high mortality and dramatic drop in egg production. Tracheal and cloacal swabs were analyzed for several poultry viruses. IBV was detected using SYBR
Green I real-time PCR detection based on the nucleocapsid (N) gene. Sequence analysis of the partial N gene indicated high similarity (~ 94%) to IBV strain 3382/06 that was isolated from Taiwan. Even though the IBV strain 3382/06 is more similar to that of the Mass type H120, the isolate has been implicated associated with intertypic recombinant of 3 putative parental IBV strains namely H120, Taiwan strain 1171/92 and China strain CK/CH/LDL/97I. Complete sequencing and antigenicity studies of the Libya IBV strains are currently underway to determine the evolution of the virus and its importance in vaccine induced immunity. In this paper we documented for the first time the presence of possibly variant IBV strain from Libya which required dramatic change in vaccination program
Biosecurity and geospatial analysis of mycoplasma infections in poultry farms at Al-Jabal Al-Gharbi region of Libya
Geospatial database of farm locations and biosecurity measures are essential to control disease outbreaks. A study was conducted to establish geospatial database on poultry farms in Al-Jabal Al-Gharbi region of Libya, to evaluate the biosecurity level of each farm and to determine the seroprevalence of mycoplasma and its relation to biosecurity level. A field team of 7 Veterinarians belongs to the National Center of Animal Health was assigned for data recording and collection of blood samples. Personal information of the producers, geographical locations, biosecurity measures and description of the poultry farms were recorded. The total number of poultry farms in Al-Jabal Al-Gharbi Region is 461 farms distributed in 13 cities. Out of these, 102 broiler farms and one broiler breeder farm (10 houses) which were in operation during team visit were included in this study. Following collection of blood, sera were separated and tested by Enzyme-linked immunosorbent assay (ELISA) for the presence of antibodies against Mycoplasma (General antigen for M. gallisepticum and M. synoviae). The seroprevalence of Mycoplasma in the region was 28% (29 poultry farms out of 103 were infected). About 50% (23 out of 47) of poultry farms located in Garian city were infected with Mycoplasma and one significant cluster of Mycoplasma infection in the city was identified. Low level of biosecurity was found in poultry farms of the region. Out of the 103 farms included, 63% of poultry houses has a ground of soil and 44% of them has uncoated walls which may influence the proper cleaning and disinfection. Almost 100% of the farms are at risk of exposure to diseases transmitted by wild birds such as avian influenza and Newcastle disease due to absence of wild birds control program. Although, 81% of the farms have entry restrictions, only 20% have disinfectants at entry which increase the risk of exposure to pathogens. The results of this study highlight the weakness points of biosecurity measures in poultry farms of Al-Jabal Al-Gharbi region and high seroprevalence of mycoplasma. Data collected in this study will assist the Veterinary authorities to apply effective disease control strategies.Keywords: Biosecurity, Geospatial analysis, Mycoplasma, Poultry
Patološko-biokemijska istraživanja hepatotoksičnosti i nefrotoksičnosti nakon izlaganja pilenki klorpirifosu i imidaklopridu
The hepatotoxicity and nephrotoxicity of chlorpyrifos (CPF) and imidacloprid (IMC) insecticides were experimentally studied in layer chickens, taking into account the patho-biochemical alterations. The LD50 values estimated were 41 mg/kg bw and 104.1 mg/kg bw for CPF and IMC, respectively. The plasma cholineesterase enzyme was severely inhibited in chickens given a single dose of CPF at a rate of 55 mg/kg bw via oral gavage, while it remained unchanged in chickens given IMC at rate of 139 mg/kg bw via similar route. The activities of liver function enzymes viz. AKP, ALT and AST were significantly increased in chickens of CPF and IMC groups. Uric acid level was significantly increased and cholesterol level was only significantly reduced in the plasma of chickens administrated CPF. Plasma glucose values in chickens given CPF as well as in chickens given IMC were significantly increased at (P<0.01) and (P<0.05), respectively. Microscopically, liver tissue of CPF intoxicated chickens showed degeneration, coagulative necrosis and hemorrhages. The kidneys showed hemorrhages, vacuolar degeneration of tubular epithelial cells as well as focal coagulative necrosis. Microscopic lesions of a similar type were observed in chickens given IMC. The exposure to CPF and IMC produced histopathological changes that could be correlated with changes in the biochemical profile of layer chickens.Hepatotoksičnost i nefrotoksičnost insekticida klorpirifosa (CPF) i imidakloprida (IMC) istraživana je u pokusima na pilenkama uzimajući u obzir patološko-biokemijske promjene. Vrijednosti LD50 iznosile su 41 mg/kg tjelesne mase za CPF i 104,1 mg/kg tjelesne mase za IMC. Aktivnost kolinesteraze u plazmi bila je zakočena u pilenki kojima je peroralno bila primijenjena jedna doza CPF u količini od 55 mg/kg, dok je ostala nepromijenjena u pilenki koje su dobile IMC također peroralno u količini od 139 mg/kg. Aktivnosti enzima koji pokazuju jetrenu funkciju, tj. AKP, ALT and AST, bile su značajno povećane u pilenki obiju skupina. Razina mokraćne kiseline bila je značajno povećana, a razina kolesterola značajno smanjena u plazmi pilenki kojima je primijenjen samo CPF. Vrijednosti glukoze u plazmi pilenki koje su dobivale CPF bile su značajno veće (P<0,01), a također i u pilenki koje su dobivale IMC (P<0,05). U jetrenom tkivu pilenki kojima je bio primijenjen CPF mikroskopski je ustanovljena degeneracija, koaugulacijska nekroza i krvarenja. Povrh koagulacijske žarišne nekroze, u bubrezima su bila ustanovljena krvarenja i vakuolarna degeneracija tubularnih epitelnih stanica. Slična mikroskopska oštećenja bila su ustanovljena u pilenki kojima je primijenjen IMC. Izlaganje klorpirifosu i imidaklopridu dovelo je do patohistoloških promjena koje su usporedive s promjenama u biokemijskom nalazu pilenki
Outbreaks of foot-and-mouth disease in Libya and Saudi Arabia during 2013 due to an exotic O/ME-SA/Ind-2001 lineage virus
Foot-and-mouth disease viruses are often restricted to specific geographical regions and spread to new areas may lead to significant epidemics. Phylogenetic analysis of sequences of the VP1 genome region of recent outbreak viruses from Libya and Saudi Arabia has revealed a lineage, O-Ind-2001, normally found in the Indian subcontinent. This paper describes the characterization of field viruses collected from these cases and provides information about a new real-time RT-PCR assay that can be used to detect viruses from this lineage and discriminate them from other endemic FMD viruses that are co-circulating in North Africa and western Eurasia.N.J. Knowles, K. Bachanek-Bankowska, J. Wadsworth, V. Mioulet, B. Valdazo-González, I.M. Eldaghayes, A.S. Dayhum, A.M. Kammon, M.A. Sharif, S. Waight, A.M. Shamia, S. Tenzin, U. Wernery, S. Grazioli, E. Brocchi, S. Subramaniam, B. Pattnaik, and D.P. Kin