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Ticks associated with the three largest wild ruminant species in Southern Africa
2007
I.G. Horak | H. Golezardy | A.C. Uys
The objective of this study was to assess the host status of the three largest southern African wild ruminants, namely giraffes, Giraffa camelopardalis, African buffaloes, Syncerus caffer, and eland, Taurotragus oryx for ixodid ticks. To this end recently acquired unpublished data are added here to already published findings on the tick burdens of these animals, and the total numbers and species of ticks recorded on 12 giraffes, 18 buffaloes and 36 eland are summarized and discussed. Twenty-eight ixodid tick species were recovered. All stages of development of ten species, namely Amblyomma hebraeum, Rhipicephalus (Boophilus) decoloratus, Haemaphysalis silacea, Ixodes pilosus group, Margaropus winthemi, Rhipicephalus appendiculatus, Rhipicephalus evertsi evertsi, Rhipicephalus glabroscutatum, Rhipicephalus maculates and Rhipicephalus muehlensi were collected. The adults of 13 species, of which the immature stages use small mammals as hosts, namely Haemaphysalis aciculifer, Hyalomma glabrum, Hyalomma marginatum rufipes, Hyalomma truncatum, Ixodes rubicundus, Rhipicephalus capensis, Rhipicephalus exophthalmos, Rhipicephalus follis, Rhipicephalus gertrudae, Rhipicephalus lounsburyi, Rhipicephalus lunulatus, Rhipicephalus pravus group and Rhipicephalus simus, were also collected.
Afficher plus [+] Moins [-]Distribution and population dynamics of ticks (Acari : Ixodidae) infesting sheep in Sennar State, Sudan
2007
M.S. Mohammed | S.M. Hassan
A cross-sectional survey of ticks infesting sheep was conducted in Sennar State, Sudan. A total body collection of ticks was carried out at five localities Sennar town, Singa, Dinder, Abu Naama and Um Banein on two types of Desert sheep (Watish and Ashgar) on two farms at each locality at two monthly intervals for one year starting July 2002 to May 2003. Four tick genera and eight species were identified. They were Amblyomma lepidum, Hyalomma anatolicum anatolicum, Hyalomma truncatum, Rhipicephalus (Boophilus) decoloratus, Rhipicephalus camicasi, Rhipicephalus evertsi evertsi, Rhipicephalus guilhoni and Rhipicephalus muhsamae. A significant (P < 0.05) seasonal pattern of activity was observed for A. lepidum and R. guilhoni with peak activity occurring during rainy seasons. The highest mean number of ticks (7.26 + 0.58) was recorded at Abu Naama, while the lowest mean (3.61 + 0.31) was recorded in Sennar. Watish type sheep carried significantly (P < 0.05) more ticks than Ashgar type.
Afficher plus [+] Moins [-]Toxo-pathological effects induced by urea in broiler chicks
2007
K. A. Abdou | M. Mubarak | A. A. Sharkawy
Sixty, day-old, chicks were reared up to 3 weeks of age and then randomly divided into 4 equal groups (3 treated and one control group). Urea (46 % nitrogen) was added to the grower-finisher ration of the treated birds at levels of 1% , 3% and 5% (groups I, II & III respectively). Feed and water were available ad libitum for all birds over the time of experiment. At days 7, 20 and 30 post exposure, 5 birds from each group were weighed, bled and sacrificed. All birds spontaneously died during the experiment were also necropsied. Haematological parameters (RBCs, WBCs counts, PCV and Hb), biochemical variables [urea, glucose, uric acid, alkaline phosphatase; (ALP) and lactate dehydrogenase; (LDH)] and body weight gain were assessed. The encountered pathological changes were described. The obtained results indicated that: (1) decrease in RBCs, WBCs counts, PCV and Hb, (2) increase in ALP, LDH, urea and uric acid, while glucose level was decreased. (3) decrease in body weight gain in all treated birds. There were significant pathological changes in kidneys, heart, liver and lungs of the treated birds. It was concluded that addition of urea to poultry feeds to replace the more expensive protein-nitrogen has serious consequences which affect the health condition and weight gain of birds.
Afficher plus [+] Moins [-]Effect of sulphadoxine-trimethoprim combination on some pharmacokinetic aspects of sulphadoxine in goats
2007
H.A.H. Zaghloul | A.A.M. El-Gendy | M.A. Tohamy | Abeer M. Radi
Some pharmacokinetic aspects of sulphadoxine alone and sulphadoxine-trimethoprim (TMP) combination were studied in goats following single intravenous (i.v) and intramuscular (i.m) administration of 15 mg kg–1 b.wt. After i.v injection the serum sulphadoxine concentration time course was best described by two compartment-open model with distribution half-lives (t0.5(.)) 2.48 and 2.31 h., elimination (t0.5(3)) half-lives 23.10 and 24.75 h., total body clearance (ClB) 0.076 and 0.073 L kg-1 h.-1 and steady state volume of distribution (Vdss) 368.54 and 411.73 ml kg-1 for sulphadoxine alone and sulphadoxine-trimethoprim combination, respectively. After i.m administration the mean peak serum concentrations (Cmax) 25.69 and 33.31 ug ml–1 were achieved after maximum time (tmax) of 3.09 and 2.79 h. for sulphadoxine alone and sulphadoxinetrimethoprim combination, respectively. The absorption half-lives (t0.5(ab)) were 0.58 and 0.42 h., respectively. It is concluded that a combination of sulphadoxine and TMP can provide a synergistic level for both antimicrobials and thus be a useful combination in the treatment of various goat diseases.
Afficher plus [+] Moins [-]Comparative descriptions of the pupae of five species of the Culicoides imicola complex (Diptera, Ceratopogonidae) from South Africa
2007
Hilda Nevill | G.J. Venter | R. Meiswinkel | E.M. Nevill
The viruses causing the economically important livestock diseases of African horse sickness (AHS) and bluetongue (BT) are transmitted by biting midges of the genus Culicoides (Diptera, Cerato po gonidae). In the Old World the most important vectors of these diseases are Culicoides imicola Kieffer, 1913, Culicoides brevitarsis Kieffer, 1917 and Culicoides bolitinos Meiswinkel, 1989. All three of these vectors belong to the Imicola complex of the subgenus Avaritia Fox, 1955. This species complex now comprises 12 sibling species; ten occur in sub-Saharan Africa and are difficult to identify (based mostly on subtle variations in the wing patterns) and so additional methods of reliable identification are needed. The pupal exuviae of the five commonest sibling species (C. imicola, C. bolitinos, Culicoides loxodontis Meiswinkel, 1992, Culicoides tuttifrutti Meiswinkel, Cornet & Dyce, 2003 and Culicoides sp. # 107) harvested from a variety of large herbivore dung types and from decaying fruits, are described and illustrated in detail. It is shown that they can be differentiated clearly on a number of morphological characters and, furthermore, are separable into two distinct groups based (principally) on the shape of the respiratory organ. A key for identifying and differentiating these five pupae is provided. Also, the pupa of the Oriental-Australasian C. brevitarsis was compared with its allopatric sister taxon, C. bolitinos. Because they share a common larval habitat (cattle and buffalo dung) and are almost inseparable in the adult phenotype, the question of their possible synonymy is raised. However, their respective pupae could not be differentiated on gross morphology and so it is argued that this unresolved problem requires a molecular solution.
Afficher plus [+] Moins [-]Light and electron microscopy of Paranella diplodae N. SP. (Polyopisthocotylea;Microcotylidae; Monogenea ) from some Red Sea Teleost fishes in Egypt
2007
E. M. Bayoumy | O. K. Abd El-Hady | M. A. Hassanain
The present study deals with a monogenean parasite infecting, some marine fish through light and scan electron microscopy. It revealed that the percentage of infection was 48% (14 out of 50 fish), 28% (14 out of 50 fish), 22% (11 out of 50 fish) and 16% (8 out of 50 fish) in Diplodus noct, Gerres oyena, Lethrinus elongates and Siganus revulatus, respectively. The present work recorded Paranaella diplodae (Polyopisthocotylea; Microcotylidae; Monogenea) as a new species collected from the investigated fish gills. They are lanculate flukes, the haptor is not distinguished from the body proper approximately 1/3 of the whole body length. The surface topography of the parasite bears small pits and conspicuous transverse folds and richly supplied with papillae-like unicellate sensory ending. The opisthohaptor is typical of Microcotylidae. The clamp structure and the haptoral tegument are similar to the rest of the body
Afficher plus [+] Moins [-]Effect of high water temperature on natural resistance of cultured Oreochromis niloticus
2007
M. N. M. Ali
Killing activity of fresh Oreochromis niloticus serum was used as an indicator of the natural immunity. Serum killing activity was tested in temperature stressed fish exposed to 32 ±1°C to different Pseudomonas fluorescens strains. As a clinical estimate of natural immunity and disease resistance, experimental challenge with P. fluorescens strains was conducted. The results cleared that serum killing activity at 32±1°C was almost stopped where fish got infected after bacterial challenge. On the other hand, control fish group kept at 23± 1°C developed serum killing activity and resistance to the acquisition of infection after challenge. A correlation was found between resistance activities of P. fluorescens strains to serum killing and their corresponding courses of infection after bacterial challenge. However, the results of experimental challenge conducted at 32±1°C suggested that the immunocompromising state resulted from the stress of inability to withstand high water temperature is exclusively the critical aspect for the induction of infection.
Afficher plus [+] Moins [-]Evaluation of Lactobacilli and active dry yeast in the prevention and control of quail colibacillosis
2007
A. S. E. D. Metwali | Jihan M. Badr | Amal I. Yoseif
Two experiments were carried out to evaluate the efficacy of the administration of active dry yeast and/or lactobacillus preparation (AVI-BAC), either before or after the infection with antibiotic resistant field strain of Escherichia coli O127 (E. coli O127) in controlling the severity of infection in quail chicks. The quail chicks of the different experimental groups were infected orally for two successive days with 3x107 CFU of E. coli O-127 as an individual dose. The used field strain proved to be highly pathogenic for quails. Probiotics were supplemented in the drinking water for the different treatment groups at a dose level of 0.5 gm/L. The results revealed that the inclusion of lactobacilli or active dry yeast before E. coli infection has been highly effective in reducing mortality rate, organ invasion and the number of E. coli positive quail chicks. In addition, it decreased the severity of macroscopic and microscopic lesions in different organs in the probiotic treated groups as comparedto the infected controls. Lactobacilli preparations were more efficient in controlling the severity of the infection. On the other hand, the administration of yeast and /or lactobacilli after inducing E. coli infection reduced the mortality rate and the severity of lesion score in different organs but probiotics failed to protect quail chicks against the infection. It has been proved that the two probiotics have synergistic effect in controlling collibacillosis in quails.
Afficher plus [+] Moins [-]Bovine Parapoxvirus: Isolation and pathogenicity studies
2007
A. S. Abdel-Moneim | S. M. Tamam
A disease characterized by papules, nodules, vesicles, pustules and ulcers on teats and udder as well as drastic drop in milk production was seen among a cattle farm in Fayoum Governorate, Egypt. A virus was isolated by inoculation of vesicle and scrap homogenate pool from infected cattle into the chorioallantoic membrane of specific pathogen free embryonated chicken eggs. The virus was identified by presence of pock lesions, intracytoplasmic inclusion bodies on the chorioallantoic membrane, polymerase chain reaction and immunohistochemistry of the inoculated membrane. A novel pathogenicity model was developed via ear pinna inoculation of Swiss mice. The virus produced vesicular and ulcerative lesions at the site of inoculation in inoculated mice. The virus identity was confirmed by the presence of intracytoplasmic viral antigens by immunohistochemistry
Afficher plus [+] Moins [-]Serodiagnostic studies on bovine leptospirosis in Beni-Suef Governorate
2007
W. H. Hassan
The present study was carried out in dairy farms experiencing low reproductive efficiency. Blood samples were collected from 84 cattle and 16 buffaloes suffered from infertility problems for detection and titration of leptospiral antibodies using the microscopic agglutination test (MAT). Eleven standardized leptospira serovars were used as living antigens for this purpose. Sixteen (19.05%) and 2 (12.5%) samples were found positive for L. interrogans serovar Icterohaemorrhagiae for cattle and buffaloes respectively, with titers ≥1:200. Antibodies against L. interrogans serovar Pomona were detected in 8 (9.52%) and 2 (12.5%) in cattle and buffaloes respectively with titers ≥1:400. Two cattle (2.38%) and two buffalo (12.5%) samples were positive for L. interrogans serovar Djasiman. On the other hand, two cattle samples were positive for both L. interrogans serovar Icterohaemorrhagiae and L. interrogans serovar Pomona. Second serum samples were rechecked for seroconversion from each positively reacted animal with 3-4 weeks interval.
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