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Ixodid ticks on dogs belonging to people in rural communities and villages in Maputo Province, Mozambique Texto completo
2008
De Matos, C.(Instituto de Investigação Agrária de Mozambique ,University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Sitoe, C.(Instituto de Investigação Agrária de Mozambique) | Neves, L.(Universidade Eduardo Mondlane Faculdade de Veterinária) | Bryson, N.R.(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Horak, I.G.(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases,Onderstepoort Veterinary Institute ,University of the Free State Department of Zoology and Entomology)
Ixodid ticks on dogs belonging to people in rural communities and villages in Maputo Province, Mozambique Texto completo
2008
De Matos, C.(Instituto de Investigação Agrária de Mozambique ,University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Sitoe, C.(Instituto de Investigação Agrária de Mozambique) | Neves, L.(Universidade Eduardo Mondlane Faculdade de Veterinária) | Bryson, N.R.(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Horak, I.G.(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases,Onderstepoort Veterinary Institute ,University of the Free State Department of Zoology and Entomology)
The species composition and geographic distribution of ixodid ticks infesting domestic dogs owned by people in rural communities and villages in Maputo Province was established by collecting ticks from dogs at each of 27 localities spread throughout the province. Ticks were collected from a total of 132 dogs, and nine species belonging to four genera were identified. One dog was infested with six species, three with five and 13 with four species. Haemaphysalis elliptica followed by Rhipicephalus simus were present on dogs at most localities, and their geographic distribution in Maputo Province has been mapped for the first time.
Mostrar más [+] Menos [-]Bovine intestinal cellular responses following primary and challenge infections with <i>Calicophoron microbothrium</i> metacercariae Texto completo
2008
N. Mavenyengwa | S. Mukaratirwa | M. Obwolo | J. Monrad
This studyw as carried out to establish whether cattle can develop resistance to re-infectionby Calicophoron microbothrium by assessing the response of intestinal mucosal globule leukocytese, osinophils, mast cells and basophils, and the establishment of the parasite in the host. A total of 241-year old Tuli steers were randomly divided into four groups of six animals each and infected with C. microbothriumm etacercariae. On the first day of the study, animals in Groups I and II were immunized with 5000 metacercariae and then challenged with 15000 metacercariae on Day 150 post immunization. Animals in Group III were immunized with 15000 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, duodenuma, bomasum 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.
Mostrar más [+] Menos [-]Production trials involving use of the FAMACHA© system for haemonchosis in sheep : preliminary results Texto completo
2008
J.A. Van Wyk
Production trials involving use of the FAMACHA© system for haemonchosis in sheep : preliminary results Texto completo
2008
J.A. Van Wyk
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.
Mostrar más [+] Menos [-]Prevalence of bovine trypanosomosis in Central Mozambique from 2002 to 2005 Texto completo
2008
E.J.K. Specht
Prevalence of bovine trypanosomosis in Central Mozambique from 2002 to 2005 Texto completo
2008
E.J.K. Specht
The study is the result of analyzing 16 895 blood smears of cattle collected at 180 sites in the provinces of Manica, Sofala, Zambézia and Tete in Mozambique. Of the blood smears 73.9 % were from Manica, 11.8 % from Tete, 8.5 % from Sofala and 5.8 % from Zambézia; 75.6 % of these were collected from smallholder cattle. Infections with trypanosomes were highest in smallholder cattle from Sofala Province with 36.8 % of the 872 blood smears examined positive for trypanosomes, and lowest in cattle of commercial farmers in Manica Province with only 6.2 % of 2 252 blood smears being positive. Trypanosoma congolense was the predominant species, followed by Trypanosoma vivax and Trypanosoma brucei sensu lato. Trypanosoma brucei, which also infects humans, was more frequent in the districts of Buzi, Mutarara and Morrumbala with 15.1 %, 10.5 % and 9.8 % of all examined cattle in 2005 being infected with it, respectively. The results show a significant increase in the infection rate with trypanosomes compared with results obtained in previous years by the Regional Veterinary Laboratory in Manica Province and by the Regional Tsetse and Trypanosomiasis Control Programme in Zambézia, Tete and Sofala provinces.
Mostrar más [+] Menos [-]Prevalence of bovine trypanosomosis in Central Mozambique from 2002 to 2005 Texto completo
2008
Specht, E.J.K.(Laboratório Regional de Veterinária)
The study is the result of analyzing 16 895 blood smears of cattle collected at 180 sites in the provinces of Manica, Sofala, Zambézia and Tete in Mozambique. Of the blood smears 73.9 % were from Manica, 11.8 % from Tete, 8.5 % from Sofala and 5.8 % from Zambézia; 75.6 % of these were collected from smallholder cattle. Infections with trypanosomes were highest in smallholder cattle from Sofala Province with 36.8 % of the 872 blood smears examined positive for trypanosomes, and lowest in cattle of commercial farmers in Manica Province with only 6.2 % of 2 252 blood smears being positive. Trypanosoma congolense was the predominant species, followed by Trypanosoma vivax and Trypanosoma brucei sensu lato. Trypanosoma brucei, which also infects humans, was more frequent in the districts of Buzi, Mutarara and Morrumbala with 15.1 %, 10.5 % and 9.8 % of all examined cattle in 2005 being infected with it, respectively. The results show a significant increase in the infection rate with trypanosomes compared with results obtained in previous years by the Regional Veterinary Laboratory in Manica Province and by the Regional Tsetse and Trypanosomiasis Control Programme in Zambézia, Tete and Sofala provinces.
Mostrar más [+] Menos [-]Acute and long-term effects of exposure to sodium monofluoroacetate (1080) in sheep Texto completo
2008
S. R. Gooneratne | C. T. Eason | L. Milne | D. G. Arthur | C. Cook | M. Wickstrom
Acute and long-term effects of exposure to sodium monofluoroacetate (1080) in sheep Texto completo
2008
S. R. Gooneratne | C. T. Eason | L. Milne | D. G. Arthur | C. Cook | M. Wickstrom
Acute and long-term effects of a single, relative lyhigh oral dose (0.25a nd 0.30 mg/kg) of sodium monofluoroacetate (1080) on the survival and productivity of sheep were evaluated to establish a better understanding of 1080 poisoning and identify more specific changes diagnostic of toxicosis. In survivors, clinical signs of acute 1080 toxicosis such as salivation and lethar gywere generally very mild. Fasted animals were more prone to 1080 toxicity. In animals that died, more severe signs, including tachypnoea, dyspnoea, and tremors occurred for 15-20 min prior to death. 1080 concentrations were highest in the blood> heart> skeletal muscle> liver. 1080 could not be detected in any of these organs of the animals that survived. Serum citratec oncentratione were elevated for 4 days after dosing. No clinical or biochemical abnormalities were found in any animal after 4 days. Histopathological lesions were most marked in the heart and lung with inflammation, necrosis, and scattered foci of fibrous tissue in the myocardium, pulmonary oedema and inflammation of the lung. No adverse longterm effects on general health or reproductive performance were observed in any sheep that survived the first 4 days following exposure to 1080. The most reliable diagnostic in dicators of 1080 exposure in sheep were measurement of its residues in blood, skeletal muscle and ruminal contents, increased serum citratec oncentratione; l evated heart rate,and characteristic electrocardiograpchh anges(up to 4 days after exposure). Death from 1080 is most likely to occur within 96 h, and animals that survived this period appeared normal.
Mostrar más [+] Menos [-]Acute and long-term effects of exposure to sodium monofluoroacetate (1080) in sheep Texto completo
2008
Gooneratne, S.R.(Cell Biology Group Agriculture and Life Sciences Division ,Centre for Environmental Toxicology Landcare Research) | Eason, C.T.(Centre for Environmental Toxicology Landcare Research ,Lincoln University Bio-Protection and Ecology Division) | Milne, L.(Centre for Environmental Toxicology Landcare Research) | Arthur, D.G.(Lincoln University LabWorks Animal Health Ltd) | Cook, C.(Ruakura Research Centre) | Wickstrom, M.(Centre for Environmental Toxicology Landcare Research ,University of Saskatchewan Western College of Veterinary Medicine)
Acute and long-term effects of a single, relatively high oral dose (0.25 and 0.30 mg/kg) of sodium monofluoroacetate (1080) on the survival and productivity of sheep were evaluated to establish a better understanding of 1080 poisoning and identify more specific changes diagnostic of toxicosis. In survivors, clinical signs of acute 1080 toxicosis such as salivation and lethargy were generally very mild. Fasted animals were more prone to 1080 toxicity. In animals that died, more severe signs, including tachypnoea, dyspnoea, and tremors occurred for 15-20 min prior to death. 1080 concentrations were highest in the blood > heart > skeletal muscle > liver. 1080 could not be detected in any of these organs of the animals that survived. Serum citrate concentrations were elevated for 4 days after dosing. No clinical or biochemical abnormalities were found in any animal after 4 days. Histopathological lesions were most marked in the heart and lung with inflammation, necrosis, and scattered foci of fibrous tissue in the myocardium, pulmonary oedema and inflammation of the lung. No adverse long-term effects on general health or reproductive performance were observed in any sheep that survived the first 4 days following exposure to 1080. The most reliable diagnostic indicators of 1080 exposure in sheep were measurement of its residues in blood, skeletal muscle and ruminal contents, increased serum citrate concentration, elevated heart rate, and characteristic electrocardiograph changes (up to 4 days after exposure). Death from 1080 is most likely to occur within 96 h, and animals that survived this period appeared normal.
Mostrar más [+] Menos [-]Helminth parasites of Natal long-fingered bats, <i>Miniopterus natalensis</i> (Chiroptera : Miniopteridae), in South Africa : research communication Texto completo
2008
K. Junker | O. Bain | J. Boomker
The helminth community infecting Miniopterus natalensis was studied at two localities, the De Hoop Nature Reserve (DHNR) (n = 57), Western Cape Province and Pretoria (n = 12), Gauteng Province, South Africa. Hosts from the DHNR had formed part of an earlier, unrelated study and were all pregnant females. A single hymenolepidid cestode species, the nematodes Molinostrongylus ornatus and Litomosa chiropterorum together with nematodes of the subfamily Capillariinae were present at both study sites, while a single digenean, Allassogonoporus sp., was only found in hosts from the DHNR. The prevalence of helminth infections was high at both localities, 68.4 % in the DHNR and 77.7 % in Pretoria, whereas the mean intensity of infection was low at the DHNR (3.76 ± 3.15), but higher in Pretoria (10.4 ± 9.9). Molinostrongylus ornatus and, to a lesser extent L. chiropterorum, were the main contributors to the higher intensities in Pretoria. The species richness ranged from 0 to 4 at both localities.
Mostrar más [+] Menos [-]EVALUATION OF EFFECTIVENESS OF CHITOSAN HYDROGEL AS HAEMOSTATIC FROM DORSAL NASAL VEINS IN RABBITS Texto completo
2008
Bassim K.Khashjoori | Abdalbari A. Alfars
The haemostatic capability, adhesion ability and biocompatibility of chitosan sponges was compared with conventional method as control group. The chitosan sponges were briefly immersed in an aqueous 20% ammonia solution before being applied to a rabbit dorsal nasal vein wound. The total amount of bleeding from the injured veins until hemostasis was similar for both chitosan and control group. The complete hemostasis success rates for both the chitosan and control group were also similar. Under hemostasis, the chitosan sponges strongly adhered to the surface of the rabbit muscles, whereas the control group. Under wet conditions, however, there was no significant difference in the adhesive ability between the two groups. During implantation, the chitosan sponges were much more flexible and resistant to breakage that good. The biocompatibilities in addition, biodegradation rates of the Chitosan sponges were very different after subcutaneous implantation in rabbit.
Mostrar más [+] Menos [-]EFFECT OF DICHLORVOS PESTICIDE ON FERTILITY OF LABORATORY MALE MICE (Mus musculus L.) Texto completo
2008
Faris Shaker Kata
Dichlorvos is one of organophosphate insect pesticides which is widely distributed in environment. This study deals with the effect of this pesticide on sperms number , sperm abnormalities and spermatogenesis in laboratory male mice (Mus musculus L.) which were treated with (0.1 mg/day , 0.05 mg/day ) of the pesticide for a period of 15 day. intraperitoneal injection of Dichlorvos in laboratory mice resulted in a significant decrease in sperms number with both doses as compared with the control group. The result also showed a significant increase of sperm abnormalities with both doses. Moreover, pesticide injection caused a significant decrease in spermatogonia and primary spermatocyte with both doses whereas the statistical analysis did not show any significant difference in tubular diameter when compared with the control group.
Mostrar más [+] Menos [-]EFFECTS OF PROLONGED EXPOSURE TO CADMIUM ON THE HEMATOPOIETIC ORGANS IN GRASS CARP (CTENOPHARYNGODON IDELLA, CYPRINIDAE) Texto completo
2008
BASIM M. JASIM
Destruction of spleen and kidney components in C. idella started on the 17th day in specimens subjected to 20 µg•L-1 Cd . The spleen was actually destructed after 73 days of exposure to 60 µg•L-1 Cd , where the two pulps can not be distinguished clearly, as the splenic blood vessels contained less blood cells . The kidney showed a complete destruction and the hematopoietic tissue lacked a distinguishable border whereas the necrosis covered large area after 60 days at 60 µg•L-1Cd . The degree of destruction was lineary proportional to concentration of toxicant and period of exposure although the period was somewhat more effective . It was concluded that the histological alterations in spleen and kidney could be used as an indicator for water pollution with cadmium and for fish health as well .
Mostrar más [+] Menos [-]STUDY OF ACUTE TOXICITY OF DIFFERENT PREPARATION OF OLEANDER LEAVES IN MICE Texto completo
2008
Lubna A. Kafi | Rana A. Sailh | Ali A. Al-Khayyat
Three preparations of dried oleander leaves were prepared. The first one was by extraction with hexane; the second by extraction with 70% ethanol while the third was suspended as a whole ground leaves in distilled water. Different concentration of each form was prepared and the range of lethal dose in mice had estimated by pilot studies. The acute toxicity study was carried out by determine the median lethal dose (LD50) after administration of each preparation using 5 subgroups (10 mice) each receive dose range from 60-64 mg/kg, 504-536 mg/kg and 1100-1300 mg/kg for the hexane extract , ethanol extract and leave suspension respectively. The lethal dose calculated by employing probit method and found to be; 62.6 mg/kg for hexane extract, 521.0 mg/kg for ethanol extract and 1164.8 for leave suspension. This result indicates that the toxic constituents of the leaves are mostly non-polar, also that the potency of toxicity is far less than that mention in some literature.
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