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Field experiences with early pregnancy diagnosis by progesterone-based ELISA in sows
2008
Boma, M.H. | Bilkei, G.
In four Kenyan pig breeding units the pregnancy diagnosis of sows has been carried out in two groups: Group 1 (n = 1911): the sows were transrectaly pregnancy tested between Days 17-22 post-mating by ultrasound. Sows testing non-pregnant immediately received one dose of 400 IU pregnant mare serum gonadotropin (PMSG) (equine chorion gonadotropin, eCG) and 200 IU human chorion gonadotropin (hCG). On showing signs of oestrous, the animals were subsequently artificially inseminated (AI). Group 2 (n = 1923): sows were pregnancy tested by serum progesterone (P4)-based enzyme-linked immunosorbent assay (ELISA) on Day 17 post-breeding. P4 concentrations were categorized as positive (> 5 ng/ml) or negative (< 5 ng/ml). Sows testing nonpregnant immediately received one dose of 400 IU PMSG and 200 IU hCG by injection, and were subsequently artificially inseminated. The following parameters were evaluated: sows diagnosed non-pregnant, days from first post-weaning insemination until the sows were inseminated at their first return to oestrus; farrowing rate and total piglets born and number of live-born piglets in litters. The percentage of sows diagnosed non-pregnant in the two groups, as well as the totals of born piglets and of live-born piglets in litters did not differ significantly between the two groups. The number of days from the first post-weaning mating until the sows were artificially inseminated at their first return to oestrus and the administration of eCG and hCG was shorter (P < 0.01) and farrowing rate was higher (P < 0.01) in the ELISA-tested sows.
Mostrar más [+] Menos [-]Detection of Anaplasma antibodies in wildlife and domestic species in wildlife-livestock interface areas of Kenya by major surface protein 5 competitive inhibition enzyme-linked immunosorbent assay
2008
Ngeranwa, J.J.N.(Kenya Agricultural Research Institute ,University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Shompole, S.P.(Kenya Agricultural Research Institute) | Venter, E.H.(Kenya Agricultural Research Institute) | Wambugu, A.(Kenya Agricultural Research Institute) | Crafford, J.E.(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases) | Penzhorn, B.L.(University of Pretoria Faculty of Veterinary Science Department of Veterinary Tropical Diseases)
The seroprevalence of Anaplasma antibodies in wildlife (eland, blue wildebeest, kongoni, impala, Thomson's gazelle, Grant's gazelle, giraffe and plains zebra) and domestic animal (cattle, sheep and goat) populations was studied in wildlife/livestock interface areas of Kenya. Serum samples were analyzed by competitive inhibition enzyme-linked immunosorbent assay (CI-ELISA), using a recombinant antigen (MSP-5) from Anaplasma marginale surface membrane. A monoclonal antibody, FC-16, was used as the primary antibody, while anti-mouse conjugated to horseradish peroxidase was used as the secondary antibody. The results indicate a high seroprevalence in both wildlife and livestock populations, in contrast to earlier reports from Kenya, which indicated a low seroprevalence. The differences are attributed to the accurate analytical method used (CI-ELISA), as compared with agglutination techniques, clinical signs and microscopy employed by the earlier workers.
Mostrar más [+] Menos [-]Evaluation of biochemical and ultrasonographic measurements as indicators of undernutrition in cattle
2008
Strydom, S.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Agenäs, S.(Swedish University of Agricultural Sciences Department of Animal Nutrition and Management Kungsangen Research Centre) | Heath, M.F.(University of Cambridge Department of Veterinary Medicine) | Phillips, C.J.C.(University of Queensland School of Veterinary Science Centre for Animal Welfare and Ethics) | Rautenbach, G.H.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Thompson, P.N.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies)
Body condition scoring (BCS) gives an indication of the nutritional status of an animal and it is thus an invaluable management tool in domestic livestock systems. It is, however, subjective. This study aimed at identifying biochemical indicators which could be objectively used as an indicator of undernutrition in ruminants. Blood samples were collected from 50 cattle with BCS < 1 and from 50 cattle with BCS > 2.5, using a 0-5 scale, and analysed for albumin, urea, creatinine, fructosamine, beta-hydroxybutyrate, non-esterified fatty acids, total serum protein and haematocrit. Rumpfat and ribfat thickness and marbling relative index were determined ultrasonographically in 15 of the low BCS group and 13 of the high BCS group. The laboratory measure with the best predictive ability for severe undernutrition was albumin, which correctly classified 94 % of cattle, using a cut-off of 31.5 g/l. In contrast to a previous study, our study did not find the fructosamine:albumin ratio to be an accurate test to indicate undernutrition in cattle. Ultrasonic measurement of subcutaneous rumpfat and ribfat proved to reliably predict undernutrition, but may, however be impractical for routine use under most field conditions.
Mostrar más [+] Menos [-]Cardiotoxic effects of pavetamine extracted from Pavetta harborii in the rat
2008
Hay, L.(University of Limpopo Department of Physiology) | Schultz, R.A.(Onderstepoort Veterinary Institute Section of Toxicology) | Schutte, P.J.(University of Limpopo Department of Physiology)
Previous studies have shown that crude extracts from Pavetta harborii as well as dried plant material have cardiotoxic effects on rats and sheep that can lead to heart failure. The active component has since been isolated and identified. This substance has been named pavetamine. The aim of this study was to determine whether pavetamine has cardiotoxic effects similar to those seen in previous reports, when administered to rats intraperitoneally. Sprague Dawley rats received two doses, initially 4 mg/kg and then 3 mg/kg pavetamine respectively and were monitored for 35 days before cardiodynamic parameters were measured by inserting a fluid-filled catheter into the left ventricle via the right carotid artery. These values were compared to those of control rats that had received only saline. Pavetamine significantly reduced systolic function and body mass in the treated rats, which indicates that it has the potential to induce heart failure in this animal model.
Mostrar más [+] Menos [-]Intramammary antibiotic withdrawal periods for dairy goats compared to those for dairy cattle
2008
Petzer, I.M.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Donkin, E.F.(University of Pretoria Faculty of Natural and Agricultural Sciences Department of Animal and Wildlife Sciences) | Du Preez, E.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Karzis, J.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Van Der Schans, T.J.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Watermeyer, J.C.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies) | Van Reenen, R.(University of Pretoria Faculty of Veterinary Science Department of Production Animal Studies)
This study investigated the withdrawal periods (WP) of two intramammary antibiotics Cloxamast LC (Intervet SA) and Spectrazol Milking Cow (Schering-Plough Animal Health) in dairy goats and compared them to those recommended for use in cattle. The WP for Cloxamast LC, measured by the Thermo Resistant Inhibitory Substances (TRIS) test, was 60 h in composite samples, 56 h in udder half samples, and the dye was visible for up to 56 h. The WP was significantly shorter than the 72 h recommended WP for use in cattle. It was however significantly longer when the 24 h safety margin (48 h) was subtracted from the recommended WP for cattle. For Spectrazol Milking Cow the antibiotics could be detected by the TRIS test for 61 h in composite samples and 59 h in udder half samples. This did not differ significantly from the recommended 60 h WP for cattle. However, it was significantly longer than that recommended for use in cattle without the 24 h safety margin. There was no significant difference in WP between infected and non-infected udder halves, while there was a weak positive correlation between WP and stage of lactation (R² = 0.253). There was a moderate positive correlation (R² = 0.583) between the TRIS test and the presence of dye in milk in udder half samples and between WP in both udder half and composite milk samples (R² = 0.456). Weak to moderate positive correlations were present between milk yield and the WP in both udder half (R² = 0.414) and composite (R² = 0.262) milk samples. Significant differences (P < 0.001) were also observed between the milk yield of udder halves with and without palpable udder damage and between samples that tested TRIS positive and negative on both composite (P = 0.008) and udder half samples (P < 0.001). There was no significant difference between the milk yield of samples with or without dye. There was a significant difference in milk yield between infected and non-infected udder halves (P = 0.054) and a weak negative correlation between milk yield and stage of lactation (R² = -0.379).
Mostrar más [+] Menos [-]Macroscopic features of the venous drainage of the reproductive system of the male ostrich (Struthio camelus)
2008
Elias, M.Z.J.(University of Pretoria Faculty of Veterinary Science Department of Anatomy and Physiology) | Aire, T.A.(University of Pretoria Faculty of Veterinary Science Department of Anatomy and Physiology) | Soley, J.T.(University of Pretoria Faculty of Veterinary Science Department of Anatomy and Physiology)
The macroscopic features of the venous drainage of the reproductive system of the male ostrich were studied in six pre-pubertal and three sexually mature and active birds. Each testis was drained by one to four testicular veins. The right testicular veins drained the right testis and epididymis and its appendix to the caudal vena cava and to the right common iliac vein, whereas the left testicular veins drained the left testis and epididymis and its appendix exclusively to the left common iliac vein. A number of variations in the drainage pattern based on the point of entry and number of testicular veins were observed. The cranial aspect of the testis was also linked to the caudal vena cava or common iliac vein via the adrenal veins. The cranial, middle and caudal segments of the ductus deferens (and ureter) were drained by the cranial, middle and caudal ureterodeferential veins respectively, to the caudal testicular veins, the caudal renal veins and pudendal/caudal part of the internal iliac veins. In some specimens, the caudal ureterodeferential veins also drained into the caudal mesenteric vein. The surface of the phallus was drained by tributaries of the pudendal vein. The basic pattern of venous drainage of the reproductive organs of the male ostrich was generally similar to that described for the domestic fowl. However, important differences, including the partial fusion of the caudal renal veins, drainage of the cranial aspect of the testes via the adrenal veins, drainage of the caudal ureterodeferential veins into the caudal mesenteric vein and the presence of veins draining the surface of the phallus, were observed. Although significant, these differences may simply reflect variations in the normal pattern of venous drainage of the reproductive tract of birds which could be verified by studying more specimens and more species.
Mostrar más [+] Menos [-]Epidemiological survey on gastro-intestinal and blood-borne helminths of dogs in north-east Gabon
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.
Mostrar más [+] Menos [-]Ixodid ticks on dogs belonging to people in rural communities and villages in Maputo Province, Mozambique
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 [-]Haemophilus paragallinarum haemagglutinin: Role in adhesion, serotyping and pathogenicity
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.
Mostrar más [+] Menos [-]Production trials involving use of the FAMACHA© system for haemonchosis in sheep: Preliminary results
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.
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