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Haemophilus paragallinarum haemagglutinin: Role in adhesion, serotyping and pathogenicity 全文
2008
Barnard, T.G.(University of the Free State Faculty of Natural and Agricultural Science Department of Microbial, Biochemical and Food Biotechnology) | Van Heerden, E.(University of the Free State Faculty of Natural and Agricultural Science Department of Microbial, Biochemical and Food Biotechnology) | Bragg, R.R.(University of the Free State Faculty of Natural and Agricultural Science Department of Microbial, Biochemical and Food Biotechnology) | Albertyn, J.(University of the Free State Faculty of Natural and Agricultural Science Department of Microbial, Biochemical and Food Biotechnology)
It is suggested that Haemophilus paragallinarum requires at least three haemagglutinins for adhesion during infection. This paper reports the partial purification and characterization of the HA-L haemagglutinin from H. paragallinarum strain 46-C3, a heat sensitive, trypsin sensitive haemagglutinin that has been shown to be the serovar specific haemagglutinin in this organism. Using the pi and molecular mass obtained, it was shown that this protein shares similarities with other types of adhesins found in Gram-negative bacteria. The haemagglutination assay conditions were optimized at pH 7.5 at 37 °C. It was also shown that activity is enhanced by the addition of Ca²+ and Mn²+ ions.
显示更多 [+] 显示较少 [-]Production trials involving use of the FAMACHA© system for haemonchosis in sheep: Preliminary results 全文
2008
van Wyk, J.A.
In three trials conducted on two separate farms the production of sheep treated for naturally acquired haemonchosis using the FAMACHA© system of targeted selective treatment (TST) (i.e. to treat only those animals unable to manage unaided in the face of heavy Haemonchus challenge) was compared to that of suppressively drenched sheep in the same flock. As expected by the research team who developed and evaluated the FAMACHA© system, TST did result in some loss in production. However, despite high levels of worm challenge in two of the trials and the fact that the comparison was with suppressive drenching which is not sustainable, the total effect was relatively small in relation to the important advantage of using the TST as regards reduced selection for anthelmintic resistance (AR). Concerning the sustainability of worm control, it is concluded that the development of drug resistance to anthelmintics leaves sheep and goat farmers in South Africa no choice but to use methods of TST such as FAMACHA©. The FAMACHA© system can also be a useful clinical aid for early on-farm detection of AR by farmers; the degree of improvement in the colour of the ocular mucous membrane from pale to red in individually drenched anaemic animals over a period of 7-14 days can give a good indication of the efficacy of the compound(s) used.
显示更多 [+] 显示较少 [-]Bovine intestinal cellular responses following primary and challenge infections with Calicophoron microbothrium metacercariae 全文
2008
Mavenyengwa, M.(University of Zimbabwe Department of Paraclinical Veterinary Studies Faculty of Veterinary Science) | Mukaratirwa, S.(University of KwaZulu-Natal School of Biological and Conservation Sciences) | Obwolo, M.(University of Zimbabwe Department of Paraclinical Veterinary Studies Faculty of Veterinary Science) | Monrad, J.(Danish Centre for Experimental Parasitology)
This study was carried out to establish whether cattle can develop resistance to re-infection by Calicophoron microbothrium by assessing the response of intestinal mucosal globule leukocytes, eosinophils, mast cells and basophils, and the establishment of the parasite in the host. A total of 24 1-year-old Tuli steers were randomly divided into four groups of six animals each and infected with C. microbothrium metacercariae. On the first day of the study, animals in Groups I and II were immunized with 5 000 metacercariae and then challenged with 15 000 metacercariae on Day 150 post-immunization. Animals in Group III were immunized with 15 000 metacercariae at the same time that Groups I and II animals were challenged to act as a positive control group. Animals in Group IV were left uninfected and acted as a negative control group. Three animals from each group were slaughtered on Day 28 post-challenge and the remainder were slaughtered on Day 42 post-challenge. The established amphistomes were recovered and histopathological and cytological examinations were done on the jejunum, duodenum, abomasum and the rumen. The establishment rates of the challenge infection in the immunized and challenged groups were lower and ranged from 0 to 0.2 % as compared to 6 %> from naive animals infected as positive controls. Animals immunized and then challenged with C. microbothrium had significantly higher eosinophil, mast cell and globule leukocytes counts in the intestinal mucosa (P < 0.05) as compared to those of the control group. The study indicates that cattle can develop resistance to C. microbothrium re-infection and that eosinophils and mast cells may be important cells in the rejection of the parasite.
显示更多 [+] 显示较少 [-]Studies on effects of lactose on experimental Trypanosoma vivax infection in Zebu cattle. 1. Plasma kinetics of intravenously administered lactose at onset of infection and pathology 全文
2008
Fatihu, M.Y.(Ahmadu Bello University Department of Veterinary Pathology and Microbiology) | Adamu, S.(Ahmadu Bello University Department of Veterinary Pathology and Microbiology) | Umar, I.A.(Ahmadu Bello University Department of Biochemistry) | Ibrahim, N.D.G.(Ahmadu Bello University Department of Veterinary Pathology and Microbiology) | Eduvie, L.O.(Ahmadu Bello University National Animal Production Research Institute) | Esievo, K.A.N.(Ahmadu Bello University Department of Veterinary Pathology and Microbiology)
Lactose in normal saline was administered intravenously to a group of Zebu cattle infected with Trypanosoma vivax to determine the blood plasma kinetics at onset of an experimental infection and its ability to protect tissues against damage as part of preliminary studies to determine its suitability for use in the treatment of trypanosomosis. Significantly (P < 0.01) higher lactose concentrations were observed in the T. vivax-infected bulls at 30 min and 1 h (P < 0.05) post-infection (p.i.) and by 4 h p.i. the plasma lactose remained above the level prior to infusion, after which it fell slightly below the pre-infusion level in the uninfected group. Calculated pharmacokinetic parameters revealed delayed excretion of lactose in the T. w'vax-infected group soon after infection. The total body clearance (CI B) was significantly (P < 0.05) reduced. The biological half-life (t ½), elimination rate constant (k e) and apparent volume of distribution (Vd) were relatively decreased (P > 0.05) as a result of the T. vivax infection. Retention of lactose in the plasma was attributed to decreased plasma clearance. It is suggested that the presence of trypanosomes in circulation rather than organic lesions could have been responsible for the delay observed in the excretion of lactose. At 12 weeks p.i., when the experiment was terminated, the group infected and given lactose infusion (despite higher parasitaemia) had no gross or histopathological lesions in the brain, spleen, lymph nodes, heart, kidneys, liver and testes. However, the group infected but not infused with lactose were emaciated, had pale mucosae, watery blood, general muscular atrophy, serous atrophy of coronary fat and other adipose tissue, hepatomegaly, splenomegaly, swollen and oedematous lymph nodes, all of which are suggestive of trypanosomosis. Histopathological lesions included narrowing of Bowman's space and hypercellularity of glomerular tufts in the kidneys with the mean glomerular tuft nuclear indices (GTNs) in the group significantly higher (P< 0.01) than the mean GTNs of the lactose-infused and control bulls. Degenerative changes occurred in the myocardium, spleen, testes and epididymides. The tesicular and epididymal lesions are indicative of male reproductive dysfunction.
显示更多 [+] 显示较少 [-]A rapid and sensitive real-time reverse transcription PCR for the pathotyping of South African H5N2 avian influenza viruses 全文
2008
Abolnik, C.(ARC-Onderstepoort Veterinary Institute)
A Fluorescence resonance energy transfer (FRET) real-time reverse-transcription (rRT-PCR) assay was developed that distinguishes stains of South African and European highly pathogenic (HPAI) from low pathogenicity (LPAI) H5 avian influenza viruses in the absence of virus isolation, irrespective of the length of insertion at the hemagglutinin cleavage site (H0). The assay was used to pathotype H5-type viruses detected by rRT-PCR in ostrich tracheal swabs collected during the 2006 HPAI H5N2 outbreak in the Western Cape Province.
显示更多 [+] 显示较少 [-]Epidemiological survey on gastro-intestinal and blood-borne helminths of dogs in north-east Gabon 全文
2008
Davoust, B.(Direction régionale du service de santé des armées de Toulon) | Normand, T.(Ecole nationale vétérinaire de Lyon Laboratoire de parasitologie ,Centre national d'instruction cynophile de la Gendarmerie Service vétérinaire) | Bourry, O.(Centre international de recherches médicales) | Dang, H.(Ecole nationale vétérinaire de Lyon Laboratoire de parasitologie) | Leroy, E.(Centre international de recherches médicales ,Institut de recherche pour le développement) | Bourdoiseau, G.(Ecole nationale vétérinaire de Lyon Laboratoire de parasitologie)
A survey of helminth parasites was carried out on 198 dogs living in almost complete liberty in villages in the northeast of Gabon. Faeces and blood samples were collected and analysed. Dirofilaria immitis antigen was detected in 13.6 % of dogs using the SNAP 3Dx® test, a commercially available enzyme-linked immunosorbent assay (ELISA). Faecal examination revealed that 91.4 % of dogs were infected by intestinal helminths. Ascarids were found in 58.5 % of the samples. Trichuris vulpis was observed in 49.5 %> of cases, and Uncinaria spp. and Ancylostoma spp. in 34.8 %>, Spirocerca lupi in 25.3 % and Capillaria spp. in 10.6 %. Cestode embryophores were found in 8.6 % of the samples.
显示更多 [+] 显示较少 [-]THE EFFECT OF PANCURONIUM BROMIDE AS A MUSCLE RELAXANT ALONE OR COMBINATION WITH DIAZEPAM IN SHEEP 全文
2008
Abdalbari A. Alfars
The effect of pancuronium bromide (0.025 mg/kg. B.W.) alone or combined with diazepam (1mg/Kg. I.V) were evaluated in six adult ewes. Pancuronium bromide alone exhibited a muscle relaxants effect, but without analgesia. All baseline measurements were taken before the administration the anesthetic agent and were repeated at 5,10,15,20 and 25 min. intervals after induction an aesthesia alone or combination with diazepam . it was found that heart rate decreased at 5 min.,but respiratory rate did change at 5-25 min. and it was significantly at 15,20 and 25 min. Pancuronium bromide – diazepam combination is responsible for declined respiratory rate and decumbency position in early stage. Pancuronium bromide – diazepam induce effective and safe an aesthesia for periods 45 minutes, due to competitive diazepam as a sedative effect of muscle relaxation. Adequate strength and duration of analgesia due to prevent impulse transmission histamine and ensured rapid and safe recovery
显示更多 [+] 显示较少 [-]PREVALENCE OF Β- LACTAMASE PRODUCING STAPHYLOCOCCUS AUREUS IN SLAUGHTERED 全文
2008
Adnan M. AL- Rodhan
Fifty liver and lung samples (25 for each) were examend for the presence of Staphylococcus aureus . The rate of S. aureus isolates were 60 and 56% in livers and lungs respectively. Identification of S. aureus isolates were performed by studying, it's cultural characteristics on mannitol salt agar and testing their pathogenicity factors (Coagulase, haemolysis and B-lactmase production), 72.4% of isolates were coagulase positive, 58.6% were β-lactamase producer, 62.1% were β-haemolytic and 37.9% were α-haemolytic. There was a difference in the ablity of S. aureus isolates to produce B-lactamase concerning the time of decolourization when iodometric assay was used.
显示更多 [+] 显示较少 [-]INVESTIGATIONAL STUDY TO CHANGES OCCUR IN CONCENTRATION OF BLOOD SERUM PROTEIN DURING PREGNANCY IN IRAQI COW 全文
2008
Rashad Fadhil Ghadhban
A study was conducted on (35) healthy Frisian cow aged (2-4) years and were grown in farms in Al-zubair region, in Basrah city This study was performed to find the effect of pregnancy on blood serum protein concentration (Total protein, Albumin, Globulin, Globulin fractions (α, β, γ). The result revealed there was significant elevation (P
显示更多 [+] 显示较少 [-]EVALUATION OF ANTIMICROBIAL ACTIVITY OF PHENOLIC EXTRAC FROM HALOXYLON SALICORNICUM 全文
2008
Abbas | M.H | B.A | Al-Saeed | R.M | and Othman
Investigation of antibacterial and antifungal activity of phenolic extract of Haloxylon salicornicum was carried out in this study on Gram positive and Gram negative pathogenic bacteria and some species of fungi. The results exhibited variable susceptibilities of microorganisms for different concentration of phenolic extract. The activity of this extract was associated with high concentrations. Using plate method, phenolic extract of H. salicornicum had the highest effect and wide diameter of growth inhibition zone against Candida albicans and Klebsiella pneumonia, and it has no effect on growth of Asprigillus fumigatus and A.. terreus only when very high concentrations is used
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