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Isolation, molecular characterization and pathogenicity studies of infectious bursal disease field virus isolates 全文
2018
M. M. Amer | K. M. El-Bayomi | M. Abd-A. Kotkat | Wafaa A. Abdel-Ghany | M. A. Shakal | Sherein S. Abdel-Gaied
This study was carried out to investigate the prevalence, molecular characterization and pathogenicity of field infectious bursal disease virus (IBDV) isolates. Nine isolates of IBDV were isolated from 13 naturally infected broiler flocks. Detection of IBDV antigen was carried out by agar gel precipitation test (AGPT), followed by virus isolation in specific pathogen free (SPF) embryonated chicken eggs (ECE) and finally molecularly characterized and identified using reverse transcriptase polymerase chain reaction (RT-PCR). The obtained nine strains of IBDV by RT-PCR were further classified by using restriction fragment length polymorphism (RFLP) technique into (4) classical, (3) variant and (2) very virulent (vv) IBDV serotype (I). The pathogenicity of the isolated IBDV strains was detected by three passages in SPF ECEs and by experimental infection of one hundred 14 days old maternally immune layer chicks. The results showed that the mortality rate of the embryos was increased by increase the number of passages till the third passage where it reached 100% for all IBDV strains and the embryos showed typical lesions of IBDV. Chicks inoculated with variant IBDV strains showed morbidity rates of 60-80 %, without mortalities. Sacrificed birds showed atrophied bursae and thymus glands and enlarged thickened proventriculus. Groups infected with classical IBDV strains showed morbidity rates 40- 60,% with mortality 0-20%. The detectable lesions were muscular hemorrhages with variable bursal lesions. Inoculated chicks with vvIBDV strains showed 50-70% morbidity and mortality of rate was 30% with lesions of muscular hemorrhages, severe nephrosis with ureates in the ureters, hemorrhagic bursitis and pin point hemorrhages on the proventricular glands. Control negative non-infected group showed neither clinical signs nor mortalities along the observation period. The histopathological effect (lesion score) of IBDV strains on the bursa, spleen and thymus glands confirmed the previously mentioned results and revealed that the highest severity (score) for these organs were induced by vv IBDV strains.
显示更多 [+] 显示较少 [-]Corrigendum: Spatial and temporal distribution of foot-and-mouth disease in four districts situated along the Uganda–Tanzania border: Implications for cross-border efforts in disease control 全文
2018
Susan D. Kerfua | Gabriel Shirima | Lughano Kusiluka | Chrisostom Ayebazibwe | Robert Mwebe | Sarah Cleaveland | Daniel Haydon
No abstract available.
显示更多 [+] 显示较少 [-]Prevalence of fungal pathogens in broiler chickens and their environment 全文
2018
Ismail A. Radwan | Ahmed H. Abed | Athar S.Abdallah.
Fungal diseases of poultry have become problematic as bacterial and viral diseases. This study was designed to investigate the prevalence of fungal agents in broiler chickens and their environment. The prevalence of fungal isolation from broiler chickens was 21.6% including 12.8% moulds and 8.8% yeast while the prevalence of fungal isolation from the environment was 46.8% including 25.5% moulds and 21.3% yeast. Aspergillus species was the most prevalent moulds while C. albicans was the most prevalent yeast recovered from broiler chickens and their environment.
显示更多 [+] 显示较少 [-]Table of Contents Vol 85, No 1 (2018) 全文
2018
Editorial Office
Some studies on helminth parasites of buff backed heron (Ardeola ibis ibis) with special reference to its role in transmision of Clinostomum complanatum in Beni-Suef Governorate. 全文
2018
S. M. Aboel Hadid | H. S. Lotfy
A number of 50 Ardeola ibis ibis birds were found harboring six nematodes species; Tetrameres species, Microtteramere species, Synhimantus invaginatus, Synhimantus equispeculatus, Ascaridia species, Paracamallanus species,and five species of trematodes; Euclinostomum heterostomum, Nephrostomum ramosum, Apharyngostrigea ibis, Apatemon gracilis and Centrocestus armatus. The most common infection by nematodes was (46%) in which highest infection rate Synhimantus invaginatus recorded (30 %) while the trematode infection was (24 %) and Apatemon gracilis was the most prevalent (16 %). Experimental infection of buff backed heron by encysted metacercaria (EMC) and exysted metacercaria (ExMC) of Clinostomum complanatum from freshwater fish Tilapia nilotica, resulted in adult worms formed after 6 days. Where the infection by EMC recorded higher worm burden (14-18 worm) and hatching percent (78%) while the infection by ExMC gave lower worm burden (7-10 worm / bird ) and hatching (48 %). In the present study, it is worthy to mention that buff backed heron act as final host model for Clinostomum complanatum and this will be helpful in further biological and immunological studies for this trematode to decrease its economic losses in fish intermediate host.
显示更多 [+] 显示较少 [-]The efficacy of diclazuril (liquid formulation) in the prevention and control of coccidiosis in broiler chicken. 全文
2018
M. M. Amer | Wafaa A. Abd el-Ghany | Aziza M. Amer | K. M. Ali | A. E. A. Hanafei | G. A. Zohair
This study was carried out to evaluate the efficacy of water soluble formulation of diclazuril (1%) in the prevention and control of mixed Eimeria infection in two experimental (semifield) trials and testing efficacy of this medicament in controlling of natural field case of mixed Eimeria infection. The experimental (semifield) trials carried out each on 150-day-old broiler chicks, as they were divided into 3 equal separate subgroups. Infected groups were orally received 1ml of an inoculum containing 50.000 sporulated oocysts of Eimeria tenella, E. acervulina and E. necatrix/ chick at 14 days of age. Diclazuril (1%) liquid at dose of 1 ml / 4 liter of drinking water for 2 successive days just after appearance of bloody dropping (at the 5th day post infection). Birds were given prophylactic diclazuril dose (1 ml / 8 liter) at the 7th day before the experimental inoculation. In both trials were oocyst count (shedding) in the dropping, dropping score, lesion score, body weight gain % and mortality rate were evaluated. Groups treated with diclazuril either in the prophylactic and curative studies gave significant and satisfactory improvement in the assessment criteria when compared with infected non medicated groups. A field trial was conducted 2 commercial broiler chicken farm consisted of 2 flocks aged 33 days; 6000 birds each. Flock (1) was kept as control positive infected non medicated group, whereas flock (2) was medicated with diclazuril (1%) at dose of 1 ml / 4 liter of the drinking water for 2 successive days. The results revealed more reduction in total oocyst count, lesion score and the mortality rate in the medicated than the infected non-treated group. The results proved that diclazuril (1%) liquid is effective in prevention and control of both experimental and field infection field circulating Eimeria species still sensitive to the drug.
显示更多 [+] 显示较少 [-]Multiplex PCR for simultaneous detection of 3 major fish pathogens incriminated in bacterial septicemic syndrome 全文
2018
Mortada M. A. Hussein | Walid H. Hassan | Aya M. A. El-Wkeel
Fish with bacterial septicemic syndrome (BSS) exhibit very similar clinical signs regardless of the etiological agents. Members of Aeromonas, Pseudomonas, Vibrio, Edwardsiella, Streptococcus and Lactococcus species are considered the most reported bacterial pathogens incriminated in such syndrome. Aeromonas hydrophila, Edwardsiella tarda and Streptococcus iniae are 3 major pathogens share in the BSS associated losses in aquaculture and considered problematic for growth of tilapia and catfish production in Egypt. Therefore, rapid and accurate diagnosis is highly needed for controlling their disease outbreaks, particularly, in mixed infections. In an attempt to elucidate the main causative pathogen, a novel multiplex PCR (m-PCR) was newly designed in this study. The developed m-PCR involves amplifying the three multiple genes in single reaction based upon primers deduced from the regions carrying 16S rRNA, etfA and 16S RNA genes of A. hydrophila (Aeromonas spp.), E. tarda and S. iniae, respectively. Prior to perform m-PCR, individual PCR assays were carried out to adapt suitable laboratory and m-PCR assays conditions. The specificity of the developed m-PCR was confirmed by the fact that only specific fragments were amplified equivalent for 953, 415 and 300 bp corresponding to A.hydrophila, E. tarda and S. iniae, respectively, and that was evident with both extracted DNAs and the bacterial cells. More specifically, these specific bands were obtained also when either the extracted DNAs or the bacterial cells of the three pathogens mixed together in the reaction. The developed m-PCR is accurate, sensitive, fast and simple technique for the simultaneous detection of A. hydrophila (Aeromonas spp.), E.tarda, and S. iniae, three major bacterial pathogens involved in BSS incidence in Egypt.
显示更多 [+] 显示较少 [-]Neonatal lamb behaviour and thermoregulation with special reference to thyroid hormones and phosphorous element: Effect of birth weight and litter size 全文
2018
R. A. Darwish | S. M. El-Bahr
New-born lambs have limited energy reserves and need a rapid access to colostrum to maintain homeothermy and survive. The object of this study was to investigate the importance of neonatal lamb behaviour in the maintenance of its body temperature and survival. The time taken to stand and suck after birth and rectal temperatures were determined in 72 crossbred lambs (progeny of crossing 1/2 Rhamani and 1/2 Finnish). In addition, blood samples were collected at 1, 24 and 72 h after birth. The obtained sera were assayed for thyroid hormones (T3 and T4), known to be involved in heat production and phosphorous element (ph) which is essential for energy metabolism. The obtained results revealed that, low birth weight and triplet lambs were behaviourally less active at birth and had less T3, T4, Ph and body temperatures values over the first 3 days of life than lambs of heavy or medium birth weight and single or twin lambs. Thus, light weight and triplet lambs were highly susceptible to hypothermia and were exposed to high rate of mortality (18.75 and 16.66%) during the neonatal period than other lambs (3.84, 10.00, 4.55, and 9.38 %, respectively). Therefore, the present study concludes that neonatal lamb behaviour, specifically success in standing and obtaining colostrum are extremely important for thermoregulation and survival of the neonate.
显示更多 [+] 显示较少 [-]Risk assessment of some residues in milk and some dairy products 全文
2018
Saadia H. El- shinawy | Gamal M. Hassan | Fayza A. Sdeek | Dina M. Ismaiel
Milk and dairy products are an important exposure route for organochlorine pesticides (OCPs) to humans. For this reason milk, kareish cheese and yoghurt analyzed for the presence of fourteen organochlorine pesticides namely Alpha HCH, Gamma HCH, Delta HCH, Aldrin, Gamma Chlordane, Endosulfan, Dieldrin, Endrin, , p,p'-DDE, p,p'-DDD, p,p'-DDT and methoxychlor using gas chromatography with electron capture detector (GC-ECD. A total of 90 random samples of raw cow's milk samples and dairy products (30 of each) were collected from 4 districts in Fayoum Governorate (Fayoum, Etssa, senoris and Tamia) during a period from September 2017 to January 2018. The results indicated that 6.60%(6/90) , 5.50%(5/90), 25.55%(23/90), 13.33%(12/9), 11.11%(10/90), 1.11%(1/90), 18.88%(17/90), 8.88%(8/90), 15.55%(14/90), 17.77%(16/90) and 22.22%(20/90) of the examined samples were contaminated with Alpha HCH, Gamma HCH, Delta HCH, Aldrin, Gamma Chlordane, Endosulfan, Dieldrin, Endrin, p,p'-DDE, p,p'-DDD and methoxychlor,respectively. None of the examined samples revealed the presence of Dichlorodiphenyltrichloroethane (p,p'-DDT), Heptachlor and Heptachlor epoxide. Generally the concentrations in the examined samples followed the order of Delta HCH > methoxychlor > Gamma HCH > p,p'-DDD > Dieldrin > Aldrin > Gamma Chlordane > Endosulfan > p,p'-DDE > Endrin > Alpha HCH.
显示更多 [+] 显示较少 [-]Molecular characterization and VP1 sequence analysis of Foot and Mouth disease new virus strains isolated during 2015-2017 in Beni-Suef, Egypt 全文
2018
Amany T. El-Gendy | Abdel-Hamid Bazid | Hanafy M. Madbouly | S.M.Tamam
Outbreaks of Foot and Mouth Disease (FMD) cause severe economic loss to the livestock industries in terms of loss of meat, milk production and the high mortality rateespecially in calves. This study was intended for detection, isolation and molecular characterization of FMDV circulated strain among different regions in Beni-Suef governorate, Egypt during 2015 and 2017. One hundred field samples were collected from clinically diseased cattle and buffaloes including vesicular fluid and sloughed epithelial membrane. Molecular detection and differentiation of FMDV serotypes by RT-PCR showed that (71%) were positive for serotype O indicating its predominance in Beni-Suef, Egypt.Also (18%) were positive for serotype SAT2 and (7%) were un-typed serotype being only positive for universal primer. Twenty samples were isolated on BHK-21 cells clone 13. Three samples showed the characteristic CPE of FMDV after blind passage 4 times. Sequences of VP1 coding-region of the three isolated FMD virus showed that the three isolated viruses were serotype O. The phylogenetic analysis of the isolated viruses reveled that they were closely related to type O of those reported in Ismailia, Behira, Giza and Cairo during 2016 with identity ranged from 97.7% - 99.8%. The most relevant outboard isolate was SUD/8/2008 with 93% identity after Blast homology search. However, the phylogenetic tree analysis revealed that the three FMDV type O isolates FMDV/serotype O/Beni-Suef/2017 differs partially from all other Egyptian serotypes of 2016. In conclusion, serotype O was the most prevalent FMDV serotype in Beni-Suef, Egypt.
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