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Burden DJ, Bartley DJ, Besier RB, Claerebout E, Elliott TP, Höglund J, Rehbein S, Torres-Acosta JFJ, Van Wyk JA, Yazwinski T. World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.): Third edition of the guideline for evaluating efficacy of anthelmintics in ruminants (bovine, ovine, caprine). Vet Parasitol 2024; 329:110187. [PMID: 38728835 DOI: 10.1016/j.vetpar.2024.110187] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2024] [Revised: 04/15/2024] [Accepted: 04/15/2024] [Indexed: 05/12/2024]
Abstract
This guideline is aimed at those who are involved in the assessment of anthelmintic efficacy in ruminant livestock species (bovine, ovine and caprine). The intent is to provide a framework that can be adopted worldwide for the testing of anthelmintics in ruminants, such that studies carried out in different countries can be compared and thereby unnecessary duplication can be reduced. Recommendations are made for the selection, housing and feeding of study animals, the type of studies required, the method used to conduct those studies, the assessment of results and the standards for defining anthelmintic efficacy.
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Affiliation(s)
- D J Burden
- Duilio Veterinary Parasitology, The Vicarage, Church Lane, Churcham, Gloucester, UK.
| | - D J Bartley
- Disease Control, Moredun Research Institute, Pentlands Science Park, Bush Loan, Penicuik, UK
| | - R B Besier
- College of Environmental and Life Sciences, Murdoch University, Perth, WA, Australia
| | - E Claerebout
- Laboratory for Parasitology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - T P Elliott
- Centre for Animal Research and Teaching, University of New England, Armidale, NSW, Australia
| | - J Höglund
- Section for Parasitology, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences, Uppsala, Sweden
| | - S Rehbein
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Rohrdorf, Germany
| | - J F J Torres-Acosta
- Facultad de Medicina Veterinaria y Zootecnia, Universidad Autónoma de Yucatán, Mérida, Yucatán, Mexico
| | - J A Van Wyk
- Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa
| | - T Yazwinski
- University of Arkansas, Fayetteville, AR, USA
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Pratsch C, Rehbein S, Werner S, Guttmann P, Stiel H, Schneider G. X-ray Fourier transform holography with beam shaping optical elements. Opt Express 2022; 30:15566-15574. [PMID: 35473273 DOI: 10.1364/oe.453747] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 04/03/2022] [Indexed: 06/14/2023]
Abstract
Holography is a powerful method for achieving 3D images of objects. Extending this method to short wavelengths potentially offers significantly higher resolution than visible light holography. However, current X-ray holography setups employ nanoscale pinholes to form the reference wave. This approach is relatively inefficient and limited to very small sample size. Here, we propose a new setup for X-ray holography based on a binary diffractive optical element (DOE), which forms at the same time the object illumination and the reference wave. This optic is located separately from the sample plane, which permits investigation of larger sample areas. Using an extended test sample, we demonstrate a resolution of 90 nm (half-pitch) at an undulator beamline at BESSY II. The new holography setup can be directly transferred to free electron laser sources enabling time-resolved nanoscale imaging for ultra-fast processes.
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Hamel D, Visser M, Mayr S, Tauchmann O, Silaghi C, Rehbein S. Bovine parafilariosis - New autochthonous cases from Germany and summary of recent reports from Europe. Vet Parasitol Reg Stud Reports 2022; 28:100678. [PMID: 35115118 DOI: 10.1016/j.vprsr.2021.100678] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 10/07/2021] [Accepted: 12/02/2021] [Indexed: 06/14/2023]
Abstract
Bovine parafilariosis is an emerging fly-borne disease in central Europe, characterized by seasonal occurrence of hemorrhagic exudations ('bleeding spots') from the end of winter to end of summer. In two cases from Germany reported here, one animal of a small herd in Bavaria and 20 animals on a farm in Baden-Württemberg presented bleeding spots from late March and late April 2020, respectively. Exudate samples from both cases were positive for larvated Parafilaria eggs. Examination of the skin and trimmed tissue after slaughter of the animal from Bavaria resulted in the collection of 11 nematodes (two males, eight females, one specimen in fragments). The animal's carcass presented typical yellow-greenish areas and bloody spots on the subcutaneous tissue of the flesh side of the skin. The nematodes were microscopically determined as Parafilaria bovicola. Basic morphometric measurements of two (one intact) male and six female nematodes are within the ranges of published data; length (male/female) 28.8/48.0-64.5 mm; width, 397.6 μm/430.7-527.6 μm; distance of cervical papillae to anterior end, 177.6/248.9-337.4; left spiculum/right spiculum (male), 365.3-379.4/149.5-180.3 μm; gubernaculum 45.0-48.1 μm; distance of vulva to anterior end (female), 37.3-66.0 mm. In order to gain information on P. bovicola in its vector, 91 cattle-visiting Musca autumnalis flies were collected from the affected animal in Bavaria (36 flies) and from co-pastured animals (55 flies) for PCR analysis and sequencing. A total of 14 flies were PCR-positive for filarial DNA, and sequencing of a fragment of the cox1 gene resulted in identification of P. bovicola (n = 10) and Thelazia gulosa (n = 5). This report presents further cases of bovine parafilariosis in Germany, provides morphometric data on male and female P. bovicola nematodes retrieved from cattle and identified DNA of P. bovicola and T.gulosa in M. autumnalis flies collected at a site of occurrence of bovine parafilariosis.
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Affiliation(s)
- D Hamel
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101 Rohrdorf, Germany.
| | - M Visser
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101 Rohrdorf, Germany
| | - S Mayr
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101 Rohrdorf, Germany
| | - O Tauchmann
- Institute of Infectology, Friedrich-Loeffler-Institute, Südufer 10, 17493 Greifswald-Insel Riems, Germany
| | - C Silaghi
- Institute of Infectology, Friedrich-Loeffler-Institute, Südufer 10, 17493 Greifswald-Insel Riems, Germany
| | - S Rehbein
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101 Rohrdorf, Germany
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Groen J, Palanca A, Aires A, Conesa JJ, Maestro D, Rehbein S, Harkiolaki M, Villar AV, Cortajarena AL, Pereiro E. Correlative 3D cryo X-ray imaging reveals intracellular location and effect of designed antifibrotic protein-nanomaterial hybrids. Chem Sci 2021; 12:15090-15103. [PMID: 34909150 PMCID: PMC8612387 DOI: 10.1039/d1sc04183e] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Accepted: 10/17/2021] [Indexed: 12/20/2022] Open
Abstract
Revealing the intracellular location of novel therapeutic agents is paramount for the understanding of their effect at the cell ultrastructure level. Here, we apply a novel correlative cryo 3D imaging approach to determine the intracellular fate of a designed protein–nanomaterial hybrid with antifibrotic properties that shows great promise in mitigating myocardial fibrosis. Cryo 3D structured illumination microscopy (cryo-3D-SIM) pinpoints the location and cryo soft X-ray tomography (cryo-SXT) reveals the ultrastructural environment and subcellular localization of this nanomaterial with spatial correlation accuracy down to 70 nm in whole cells. This novel high resolution 3D cryo correlative approach unambiguously locates the nanomaterial after overnight treatment within multivesicular bodies which have been associated with endosomal trafficking events by confocal microscopy. Moreover, this approach allows assessing the cellular response towards the treatment by evaluating the morphological changes induced. This is especially relevant for the future usage of nanoformulations in clinical practices. This correlative super-resolution and X-ray imaging strategy joins high specificity, by the use of fluorescence, with high spatial resolution at 30 nm (half pitch) provided by cryo-SXT in whole cells, without the need of staining or fixation, and can be of particular benefit to locate specific molecules in the native cellular environment in bio-nanomedicine. A novel 3D cryo correlative approach locates designed therapeutic protein–nanomaterial hybrids in whole cells with high specificity and resolution. Detection of treatment-induced morphological changes, crucial for pre-clinical studies, are revealed.![]()
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Affiliation(s)
- J Groen
- MISTRAL Beamline, Experiments Division, ALBA Synchrotron Light Source Cerdanyola del Valles 08290 Barcelona Spain
| | - A Palanca
- Instituto de Biomedicina y Biotecnologia de Cantabria (IBBTEC), University of Cantabria, CSIC 39011 Santander Spain.,Department of Anatomy and Cell Biology, University of Cantabria 39011 Santander Spain
| | - A Aires
- Center for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA) Paseo de Miramón 194 20014 Donostia San Sebastian Spain
| | - J J Conesa
- MISTRAL Beamline, Experiments Division, ALBA Synchrotron Light Source Cerdanyola del Valles 08290 Barcelona Spain .,National Center for Biotechnology CSIC (CNB-CSIC), Department of Macromolecular Structures Cantoblanco 28049 Madrid Spain
| | - D Maestro
- Instituto de Biomedicina y Biotecnologia de Cantabria (IBBTEC), University of Cantabria, CSIC 39011 Santander Spain
| | - S Rehbein
- Helmholtz-Zentrum Berlin für Materialien und Energie, Bessy II D-12489 Berlin Germany
| | - M Harkiolaki
- Beamline B24, Diamond Light Source, Harwell Science and Innovation Campus Didcot Oxfordshire OX11 0DE UK
| | - A V Villar
- Instituto de Biomedicina y Biotecnologia de Cantabria (IBBTEC), University of Cantabria, CSIC 39011 Santander Spain.,Department of Physiology and Pharmacology, University of Cantabria Avd. Herrera Oria s/n Santander Spain
| | - A L Cortajarena
- Center for Cooperative Research in Biomaterials (CIC biomaGUNE), Basque Research and Technology Alliance (BRTA) Paseo de Miramón 194 20014 Donostia San Sebastian Spain .,Ikerbasque, Basque Foundation for Science 48009 Bilbao Spain
| | - E Pereiro
- MISTRAL Beamline, Experiments Division, ALBA Synchrotron Light Source Cerdanyola del Valles 08290 Barcelona Spain
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Rehbein S, Mihalca AD. First report of the dog louse fly Hippobosca longipennis in Romania. Med Vet Entomol 2021; 35:251-253. [PMID: 33368413 DOI: 10.1111/mve.12498] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Affiliation(s)
- S Rehbein
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Rohrdorf, Germany
| | - A D Mihalca
- Department of Parasitology and Parasitic Diseases, University of Agricultural Sciences and Veterinary Medicine of Cluj-Napoca, Cluj-Napoca, Romania
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Rehbein S. The occurrence of Lipoptena hippoboscids in Europe: a subject of potential misperception? Med Vet Entomol 2021; 35:254-256. [PMID: 33410524 DOI: 10.1111/mve.12508] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Affiliation(s)
- S Rehbein
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Rohrdorf, Germany
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Rehbein S, Visser M, Hamel D, Reindl H. Correction to: Occurrence of the giant liver fluke, Fascioloides magna, in sympatric wild ungulates in one area in the Upper Palatinate Forest (northeastern Bavaria, Germany). Parasitol Res 2021; 120:1521. [PMID: 33615413 DOI: 10.1007/s00436-021-07090-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Affiliation(s)
- S Rehbein
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Walchenseestr 8-12, 83101, Rohrdorf, Germany.
| | - M Visser
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Walchenseestr 8-12, 83101, Rohrdorf, Germany
| | - D Hamel
- Boehringer Ingelheim Vetmedica GmbH, Kathrinenhof Research Center, Walchenseestr 8-12, 83101, Rohrdorf, Germany
| | - H Reindl
- Tierärztliche Fachpraxis für Kleintiere, Schießtrath 12, 92709, Moosbach, Germany
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Tielemans E, Lebon W, Dumont P, Taweethavonsawat P, Larsen D, Rehbein S. Efficacy of afoxolaner plus milbemycin oxime chewable tablets (NexGard Spectra ®, Merial) against adult Ancylostoma ceylanicum hookworm, in dogs. Vet Parasitol 2017; 238:87-89. [PMID: 28408213 DOI: 10.1016/j.vetpar.2017.03.028] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2016] [Revised: 01/30/2017] [Accepted: 03/31/2017] [Indexed: 10/19/2022]
Abstract
A fixed-combination chewable tablet incorporating afoxolaner plus milbemycin oxime (NexGard Spectra®, Merial) was tested in purpose-bred Beagle dogs for efficacy against adult Ancylostoma ceylanicum hookworms. Sixteen dogs were inoculated each by oral administration of approximately 500 infective larvae of A. ceylanicum. Seventeen days after inoculation, the dogs were weighed and allocated randomly to be treated with afoxolaner plus milbemycin oxime chewable tablets or to remain untreated. Commercial chewable tablets of different strength were combined to deliver doses as close as possible to the minimum effective dose of 2.5mg afoxolaner plus 0.5mg milbemycin oxime per kg body weight. Parasites were recovered and counted for determination of efficacy seven days after treatment. All eight dogs that had been left untreated were harboring adult A. ceylanicum (geometric mean, 317.8; range, 210-428) while only one and nine A. ceylanicum were recovered from two of the eight dogs treated with afoxolaner plus milbemycin oxime chewable tablets (geometric mean, 0.5; p<0.0001). Thus, 99.9% efficacy against induced infection of A. ceylanicum was obtained by the use of oral NexGard Spectra® at the minimum effective dose. Treatment with afoxolaner plus milbemycin oxime chewable tablets was well accepted and safe.
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Affiliation(s)
- E Tielemans
- Merial SAS, Centre de Recherche de Saint-Vulbas, 850 allée des Cyprès, 01150 Saint Vulbas, France
| | - W Lebon
- Merial SAS, Centre de Recherche de Saint-Vulbas, 850 allée des Cyprès, 01150 Saint Vulbas, France
| | - P Dumont
- Merial SAS, Centre de Recherche de Saint-Vulbas, 850 allée des Cyprès, 01150 Saint Vulbas, France
| | - P Taweethavonsawat
- Faculty of Veterinary Science, Chulongkorn University, Bangkok 10330, Thailand
| | - D Larsen
- Merial, Inc., 3239 Satellite Blvd., Duluth, GA 30096, USA
| | - S Rehbein
- Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101 Rohrdorf, Germany.
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Letendre L, Harriman J, Drag M, Mullins A, Malinski T, Rehbein S. The intravenous and oral pharmacokinetics of afoxolaner and milbemycin oxime when used as a combination chewable parasiticide for dogs. J Vet Pharmacol Ther 2016; 40:35-43. [PMID: 27604405 DOI: 10.1111/jvp.12332] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2015] [Accepted: 05/06/2016] [Indexed: 11/28/2022]
Abstract
The pharmacokinetics of afoxolaner and milbemycin oxime (A3 and A4 forms) in dogs were evaluated following the oral administration of NexGard Spectra® (Merial), a fixed combination chewable formulation of these two active pharmaceutical ingredients. Absorption of actives was rapid at levels that provide the minimum effective doses of 2.5 mg/kg and 0.5 mg/kg of afoxolaner and milbemycin oxime, respectively. The time to maximum afoxolaner plasma concentrations (tmax ) was 2-4 h. The milbemycin tmax was 1-2 h. The terminal plasma half-life (t1/2 ) and the oral bioavailability were 14 ± 3 days and 88.3% for afoxolaner, 1.6 ± 0.4 days and 80.5% for milbemycin oxime A3 and 3.3 ± 1.4 days and 65.1% for milbemycin oxime A4. The volume of distribution (Vd ) and systemic clearance (Cls) were determined following an IV dose of afoxolaner or milbemycin oxime. The Vd was 2.6 ± 0.6, 2.7 ± 0.4 and 2.6 ± 0.6 L/kg for afoxolaner, milbemycin oxime A3 and milbemycin oxime A4, respectively. The Cls was 5.0 ± 1.2, 75 ± 22 and 41 ± 12 mL/h/kg for afoxolaner, milbemycin oxime A3 and milbemycin oxime A4, respectively. The pharmacokinetic profile for the combination of afoxolaner and milbemycin oxime supports the rapid onset and a sustained efficacy for afoxolaner against ectoparasites and the known endoparasitic activity of milbemycin oxime.
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Affiliation(s)
| | | | - M Drag
- Merial, Inc., Duluth, GA, USA
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Rehbein S, Visser M, Meyer M, Lindner T. Ivermectin treatment of bovine psoroptic mange: effects on serum chemistry, hematology, organ weights, and leather quality. Parasitol Res 2015; 115:1519-28. [DOI: 10.1007/s00436-015-4885-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2015] [Accepted: 12/11/2015] [Indexed: 11/30/2022]
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Sommer MF, Beck R, Ionita M, Stefanovska J, Vasić A, Zdravković N, Hamel D, Rehbein S, Knaus M, Mitrea IL, Shukullari E, Kirkova Z, Rapti D, Capári B, Silaghi C. Multilocus sequence typing of canine Giardia duodenalis from South Eastern European countries. Parasitol Res 2015; 114:2165-74. [PMID: 25804971 DOI: 10.1007/s00436-015-4405-3] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2015] [Accepted: 02/27/2015] [Indexed: 11/24/2022]
Abstract
Giardia duodenalis is a worldwide occurring protozoan that can infect various mammalian hosts. While living conditions are getting closer between pet animals and owners, there is discussion whether dogs may contribute to the transmission of these pathogens to humans. The present study was conducted in order to identify the Giardia assemblages in dogs from South Eastern Europe. For this purpose, 1645 faecal samples of household and shelter dogs from Albania, Bulgaria, Hungary, Macedonia, Romania and Serbia were tested for Giardia coproantigen by enzyme-linked immunosorbent assay (ELISA). A subset of 107 faecal samples demonstrating Giardia cysts by direct immunofluorescence assay (IFA) or microscopy (15-22 per country) plus 26 IFA-positive canine faecal samples from Croatia were used for DNA extraction and multilocus sequence typing with nested PCRs targeting five different gene loci: SSU rRNA, ITS1-5.8S-ITS2, beta giardin (bg), glutamate dehydrogenase (gdh) and triosephosphate isomerase (tpi). One third (33.7%) of the samples tested positive for Giardia antigen in the coproantigen ELISA. Shelter dogs were infected more frequently than household dogs (57.2 vs. 29.7%, p < 0.01). Amplification was obtained in 82.0, 12.8, 11.3, 1.5, and 31.6%, of the investigated samples at the SSU rRNA, bg, gdh and tpi loci and the ITS1-5.8S-ITS2 region, respectively. The dog-specific assemblages C and D were identified in 50 and 68 samples, respectively. The results demonstrate that G. duodenalis should be considered as a common parasite in dogs from South Eastern Europe. However, there was no evidence for zoonotic Giardia assemblages in the investigated canine subpopulation.
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Affiliation(s)
- M F Sommer
- Institute of Comparative Tropical Medicine and Parasitology, Ludwig-Maximilians-Universität, Munich, Leopoldstr. 5 80802, München, Germany,
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Blutke A, Börjes P, Herbach N, Pfister K, Hamel D, Rehbein S, Wanke R. Acaricide treatment prevents adrenocortical hyperplasia as a long-term stress reaction to psoroptic mange in cattle. Vet Parasitol 2015; 207:125-33. [DOI: 10.1016/j.vetpar.2014.10.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 09/27/2014] [Accepted: 10/07/2014] [Indexed: 11/30/2022]
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Rehbein S, Knaus M, Visser M, Winter R, Yoon S, Anderson A, Cramer L. Erratum to: Activity of ivermectin long-acting injectable (IVOMEC(®) GOLD) in first-season grazing cattle exposed to natural challenge conditions in Germany. Parasitol Res 2014; 114:343-5. [PMID: 25391497 DOI: 10.1007/s00436-014-4184-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S Rehbein
- Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101, Rohrdorf, Germany,
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Rehbein S, Knaus M, Visser M, Winter R, Yoon S, Anderson A, Cramer L. Activity of ivermectin long-acting injectable (IVOMEC(®) GOLD) in first-season grazing cattle exposed to natural challenge conditions in Germany. Parasitol Res 2014; 114:47-54. [PMID: 25280515 DOI: 10.1007/s00436-014-4158-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2014] [Accepted: 09/23/2014] [Indexed: 10/24/2022]
Abstract
The persistent activity of ivermectin long-acting injection (IVM LAI; IVOMEC® GOLD, Merial; 3.15% ivermectin w/v) against nematode infections of cattle was evaluated under natural challenge conditions. Seventy nematode-free Brown Swiss calves were blocked by pre-treatment bodyweight and allocated randomly to seven groups of 10 animals each: saline (control) at 1 mL/50 kg bodyweight once on day 0 or IVM LAI at 1 mL/50 kg bodyweight (630 mcg IVM/kg) on either days 0, 7, 14, 21, 28, or 35. After housing until day 35, calves were grazed as one herd on a naturally contaminated pasture for 42 days. Calves were then weighed and housed for 4 weeks before being necropsied for parasite counting. Treatment with IVM LAI prevented the establishment (>90%, p < 0.05) of Dictyocaulus viviparus (100%), Bunostomum phlebotomum (100 %), Haemonchus contortus (98.6%), Ostertagia ostertagi/lyrata (94.9%), and Oesophagostomum radiatum (93.3%) for at least 77 days; Ostertagia leptospicularis (99.1%) for 63 days; Cooperia punctata (97.7%), Trichostrongylus axei (96.5%), and Ostertagia spp. inhibited larvae 4 (93.3%) for 56 days; Cooperia oncophora/surnabada (96.9%), Trichuris discolor (93.6%), and Cooperia spp. inhibited larvae 4 (98.8%); and Nematodirus spp. inhibited larvae 4 (97.1%) for 42 days. Calves of groups treated with IVM LAI had significantly (p < 0.001) higher days 0 to 77 weight gains than the saline-treated controls (28.40-39.25 vs 2.60 kg); the weight gains of the IVM LAI-treated groups, however, were not different from one another (p > 0.3). This study demonstrated a very high efficacy of IVOMEC® GOLD in preventing the establishment of a wide range of bovine nematodes for extended periods of time which was associated with a significant benefit to productivity in terms of weight gain.
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Affiliation(s)
- S Rehbein
- Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101, Rohrdorf, Germany,
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Guttmann P, Rehbein S, Werner S, Henzler K, Tarek B, Schneider G. Nanoscale spectroscopy and tomography with the HZB X-ray microscope: Applications in materials and life sciences. ACTA ACUST UNITED AC 2013. [DOI: 10.1088/1742-6596/463/1/012032] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Visser M, Löwenstein M, Yoon S, Rehbein S. The treatment of bovine sarcoptic mange (Sarcoptes scabiei var. bovis) using eprinomectin extended-release injection. Vet Parasitol 2013; 192:359-64. [DOI: 10.1016/j.vetpar.2012.11.043] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Hunter J, Yoon S, Yazwinski T, Williams J, Rehbein S. The efficacy of eprinomectin extended-release injection against naturally acquired nematode parasites of cattle, with special regard to inhibited fourth-stage Ostertagia larvae. Vet Parasitol 2013; 192:346-52. [DOI: 10.1016/j.vetpar.2012.11.041] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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18
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Rehbein S, Holste JE, Smith LL, Lloyd JL. The efficacy of eprinomectin extended-release injection against Hypoderma spp. (Diptera: Oestridae) in cattle. Vet Parasitol 2012; 192:353-8. [PMID: 23273587 DOI: 10.1016/j.vetpar.2012.11.042] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The efficacy of eprinomectin in an extended-release injection (ERI) formulation was determined in cattle harboring naturally acquired infestations of first- or second- and third-stage larvae of Hypoderma spp. in three studies conducted according to the same protocol in the USA (two studies) and Germany (one study). Thirty cattle sourced from herds with a history of Hypoderma infestation were included in each study. Cattle were formed into replicates of three animals each on the basis of pre-treatment anti-Hypoderma antibody titers. Within replicates each animal was randomly allocated to one of the following treatments: ERI vehicle (control) at 1 mL/50 kg bodyweight, administered once on Day 0; Eprinomectin 5% ERI at 1 mL/50 kg bodyweight (1.0 mg eprinomectin/kg), administered once on Day 0 (when larvae were expected to be first instars); or Eprinomectin 5% ERI at 1 mL/50 kg bodyweight (1.0 mg eprinomectin/kg), administered once when larvae were second or third instars (study dependent, Day 73, 119, or 140). Treatments were administered by subcutaneous injection in front of the shoulder. In all studies, emerging and/or expressed Hypoderma larvae were recovered, speciated, and counted and viability was determined. Eprinomectin LAI treatment was 100% (p<0.05) efficacious against first- and second- or third-stage larvae of Hypoderma bovis (two studies) and Hypoderma lineatum (one study). All animals accepted the treatment well. No adverse reaction to treatments was observed in any animal in any study.
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Affiliation(s)
- S Rehbein
- Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101 Rohrdorf, Germany.
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19
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Rehbein S, Baggott DG, Johnson EG, Kunkle BN, Yazwinski TA, Yoon S, Cramer LG, Soll MD. Nematode burdens of pastured cattle treated once at turnout with eprinomectin extended-release injection. Vet Parasitol 2012; 192:321-31. [PMID: 23273928 DOI: 10.1016/j.vetpar.2012.11.038] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The efficacy of eprinomectin in an extended-release injection (ERI) formulation was evaluated against infections with third-stage larvae or eggs of gastrointestinal and pulmonary nematodes in cattle under 120-day natural challenge conditions in a series of five studies conducted in the USA (three studies) and in Europe (two studies). For each study, 30 nematode-free (four studies) or 30 cattle harboring naturally acquired nematode infections (one study) were included. The cattle were of various breeds or crosses, weighed 107.5-273 kg prior to treatment and aged approximately 4-11 months. For each study, animals were blocked based on pre-treatment bodyweight and then randomly allocated to treatment: ERI vehicle (control) at 1 mL/50 kg bodyweight or Eprinomectin 5% (w/v) ERI at 1 mL/50 kg bodyweight (1.0 mg eprinomectin/kg) for a total of 15 and 15 animals in each group. Treatments were administered once on Day 0 by subcutaneous injection in front of the shoulder. In each study, all animals grazed one naturally contaminated pasture for 120 days. At regular intervals during the studies, fecal samples from all cattle were examined for nematode egg and larval counts. In four studies pairs of tracer cattle were used to monitor pasture infectivity at 28-day intervals before and/or during the grazing period. All calves were weighed before turnout onto pasture and at regular intervals until housing on Day 120. For parasite recovery, all study animals were humanely euthanized 27-30 days after removal from pasture. Cattle treated with Eprinomectin ERI had significantly (p<0.05) fewer strongylid eggs (≤1 egg per gram; egg count reduction≥94%) than the control cattle and zero lungworm larvae at each post-treatment time point. At euthanasia, cattle treated with Eprinomectin ERI had significantly (p<0.05) fewer of the following nematodes than the ERI vehicle-treated (control) cattle with overall reduction of nematode counts by >92%: Dictyocaulus viviparus (adults and fourth-stage larvae (L4), Bunostomum phlebotomum, Cooperia curticei, Cooperia oncophora, Cooperia punctata, Cooperia surnabada, Cooperia spp. inhibited L4, Haemonchus contortus, Haemonchus placei, Haemonchus spp. inhibited L4, Nematodirus helvetianus, Nematodirus spp. inhibited L4, Oesophagostomum radiatum, Oesophagostomum spp. inhibited L4, Ostertagia leptospicularis, Ostertagia lyrata, Ostertagia ostertagi, Ostertagia spp. inhibited L4, Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus spp. inhibited L4, Trichuris discolor, and Trichuris ovis. Over the 120-day grazing period, Eprinomectin ERI-treated cattle gained between 4.8 kg and 31 kg more weight than the controls. This weight gain advantage was significant (p<0.05) in three studies. All animals accepted the treatment well. No adverse reaction to treatment was observed in any animal in any study.
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Affiliation(s)
- S Rehbein
- Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101 Rohrdorf, Germany.
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20
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Legall H, Blobel G, Stiel H, Sandner W, Seim C, Takman P, Martz DH, Selin M, Vogt U, Hertz HM, Esser D, Sipma H, Luttmann J, Höfer M, Hoffmann HD, Yulin S, Feigl T, Rehbein S, Guttmann P, Schneider G, Wiesemann U, Wirtz M, Diete W. Compact x-ray microscope for the water window based on a high brightness laser plasma source. Opt Express 2012; 20:18362-9. [PMID: 23038387 DOI: 10.1364/oe.20.018362] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We present a laser plasma based x-ray microscope for the water window employing a high-average power laser system for plasma generation. At 90 W laser power a brightness of 7.4 x 10(11) photons/(s x sr x μm(2)) was measured for the nitrogen Lyα line emission at 2.478 nm. Using a multilayer condenser mirror with 0.3 % reflectivity 10(6) photons/(μm(2) x s) were obtained in the object plane. Microscopy performed at a laser power of 60 W resolves 40 nm lines with an exposure time of 60 s. The exposure time can be further reduced to 20 s by the use of new multilayer condenser optics and operating the laser at its full power of 130 W.
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Affiliation(s)
- H Legall
- Max-Born-Institut, Max-Born-Str. 2A, D-12489 Berlin, Germany.
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21
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Mayer M, Grévent C, Szeghalmi A, Knez M, Weigand M, Rehbein S, Schneider G, Baretzky B, Schütz G. Multilayer Fresnel zone plate for soft X-ray microscopy resolves sub-39nm structures. Ultramicroscopy 2011; 111:1706-11. [PMID: 22088445 DOI: 10.1016/j.ultramic.2011.09.003] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2011] [Revised: 07/26/2011] [Accepted: 09/01/2011] [Indexed: 11/18/2022]
Abstract
Best resolutions in X-ray focusing are obtained to date by using diffractive lenses called Fresnel zone plates (FZPs). Their further improvement is nevertheless hindered by fundamental limitations in the employed manufacturing techniques. Here, we show a novel method to fabricate FZPs based on multilayer deposition with atomic layer deposition (ALD) and subsequent sectioning with focused ion beam (FIB). For the first time a multilayer FZP working in the soft X-ray range was prepared and could achieve the best resolution obtained so far for multilayer FZPs by resolving features below 39nm in size in a scanning soft X-ray microscope. The new technique presents high potential for high resolution microscopy in both the soft and hard X-ray range.
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Affiliation(s)
- M Mayer
- Max-Planck-Institute for Intelligent Systems, Heisenbergstr. 3, 70569 Stuttgart, Germany
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22
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Heine R, Gorniak T, Nisius T, Christophis C, Pettitt M, Staier F, Wilhein T, Rehbein S, Grunze M, Rosenhahn A. Digital in-line X-ray holography with zone plates. Ultramicroscopy 2011; 111:1131-6. [DOI: 10.1016/j.ultramic.2011.02.002] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2010] [Revised: 02/01/2011] [Accepted: 02/05/2011] [Indexed: 11/15/2022]
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23
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Baggott D, Casartelli A, Fraisse F, Manavella C, Marteau R, Rehbein S, Wiedemann M, Yoon S. Demonstration of the metaphylactic use of gamithromycin against bacterial pathogens associated with bovine respiratory disease in a multicentre farm trial. Vet Rec 2011; 168:241. [PMID: 21493573 PMCID: PMC3361959 DOI: 10.1136/vr.c6776] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
On five commercial cattle rearing sites across Europe, a total of 802 young cattle at high risk of developing bovine respiratory disease (BRD) associated with the bacterial pathogens Mannheimia haemolytica or Pasteurella multocida and/or Mycoplasma bovis were enrolled into a multicentre, controlled field trial. Half were treated with a single dose of gamithromycin at 6 mg/kg bodyweight by subcutaneous injection and half received an injection of a saline placebo as the control. All animals were observed daily for 14 days for signs of BRD as defined by set criteria. The proportion of metaphylactic preventive treatment successes, defined as animals surviving to day 14 without signs of BRD, in the gamithromycin-treated group (86 per cent) was significantly (P=0.0012) higher than in the saline-treated controls (61 per cent). Morbidity among the treated animals was reduced by 64 per cent compared with the controls.
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Affiliation(s)
- D Baggott
- Merial, Centre de Recherche de Saint Vulbas, Parc Industriel de la Plaine de l'Aine, Allee des Cypres, 01150 Saint Vulbas, France.
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24
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Heim S, Guttmann P, Rehbein S, Werner S, Schneider G. Energy-tunable full-field x-ray microscopy: Cryo-tomography and nano-spectroscopy with the new BESSY TXM. ACTA ACUST UNITED AC 2009. [DOI: 10.1088/1742-6596/186/1/012041] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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25
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26
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Rehbein S, Heim S, Guttmann P, Werner S, Schneider G. Ultrahigh-resolution soft-x-ray microscopy with zone plates in high orders of diffraction. Phys Rev Lett 2009; 103:110801. [PMID: 19792359 DOI: 10.1103/physrevlett.103.110801] [Citation(s) in RCA: 56] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Revised: 08/25/2009] [Indexed: 05/15/2023]
Abstract
We present an x-ray optical approach to overcome the current limitations in spatial resolution of x-ray microscopes. Our new BESSY full-field x-ray microscope operates with an energy resolution up to E/DeltaE=10(4). We demonstrate that under these conditions it is possible to employ high orders of diffraction for imaging. Using the third order of diffraction of a zone plate objective with 25 nm outermost zone width, 14 nm lines and spaces of a multilayer test structure were clearly resolved. We believe that high-order imaging paves the way towards sub-10-nm real space x-ray imaging.
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Affiliation(s)
- S Rehbein
- Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, Elektronenspeicherring BESSY II, Albert-Einstein-Strasse 15, 12489 Berlin, Germany
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27
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Hamers C, Rehbein S, Hudelet P, Blanchet M, Lapostolle B, Cariou C, Duboeuf M, Goutebroze S. Protective duration of immunity of an inactivated bluetongue (BTV) serotype 2 vaccine against a virulent BTV serotype 2 challenge in sheep. Vaccine 2009; 27:2789-93. [DOI: 10.1016/j.vaccine.2009.02.099] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Revised: 02/20/2009] [Accepted: 02/26/2009] [Indexed: 12/01/2022]
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28
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Rehbein S, Visser M, Yoon S, Marley SE. Efficacy of a combination ivermectin/praziquantel paste against nematodes, cestodes and bots in naturally infected ponies. Vet Rec 2007; 161:722-4. [DOI: 10.1136/vr.161.21.722] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Affiliation(s)
- S. Rehbein
- Merial, Kathrinenhof Research Centre; Walchenseestrasse 8-12 D-83101 Rohrdorf Germany
| | - M. Visser
- Merial, Kathrinenhof Research Centre; Walchenseestrasse 8-12 D-83101 Rohrdorf Germany
| | - S. Yoon
- Merial, 3239 Satellite Boulevard Duluth GA 30096 USA
| | - S. E. Marley
- Merial, 3239 Satellite Boulevard Duluth GA 30096 USA
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Schneider G, Guttmann P, Heim S, Rehbein S, Eichert D, Niemann B. X-Ray Microscopy at BESSY: From Nano-Tomography to Fs-Imaging. ACTA ACUST UNITED AC 2007. [DOI: 10.1063/1.2436300] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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30
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Holdsworth PA, Kemp D, Green P, Peter RJ, De Bruin C, Jonsson NN, Letonja T, Rehbein S, Vercruysse J. World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guidelines for evaluating the efficacy of acaricides against ticks (Ixodidae) on ruminants. Vet Parasitol 2006; 136:29-43. [PMID: 16377090 DOI: 10.1016/j.vetpar.2005.11.011] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
These guidelines have been prepared to assist in the planning, conduct and interpretation of studies for the assessment of the efficacy of acaricides (excluding vaccines and other bio-control agents) against single and multi-host ticks (Ixodidae) on ruminants. Information is provided on the selection of animals, dose determination, dose confirmation and field studies, record keeping and result interpretation. The use of pen facilities is advocated for dose determination and confirmation studies for defining therapeutic and persistent efficacy. A minimum of two studies per tick species for which claims are sought is recommended for each dose determination and dose confirmation investigation. If dose confirmation studies demonstrate greater than 95% efficacy the sponsor may proceed to field studies, where a minimum of two studies per geographical location is preferred to confirm the therapeutic and persistent efficacy under field conditions. If dose confirmation studies demonstrate less than 95% efficacy then longer-term field studies can be conducted over two tick seasons with a minimum of two studies per geographical location. These studies can incorporate other control methods such as tick vaccines, to demonstrate stable long-term tick management. Specific advice is also given on conducting studies with paralysis ticks. These guidelines are also intended to assist investigators on how to conduct specific experiments, to provide specific information for registration authorities involved in the decision-making process, to assist in the approval and registration of new acaricides, and to facilitate the worldwide adoption of standard procedures.
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Affiliation(s)
- P A Holdsworth
- Avcare Limited, Locked Bag 916, Canberra 2601, ACT, Australia.
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31
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Holdsworth PA, Vercruysse J, Rehbein S, Peter RJ, De Bruin C, Letonja T, Green P. World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guidelines for evaluating the efficacy of ectoparasiticides against myiasis causing parasites on ruminants. Vet Parasitol 2006; 136:15-28. [PMID: 16359802 DOI: 10.1016/j.vetpar.2005.11.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Abstract
These guidelines have been prepared to assist in the planning, conduct and interpretation of studies for the assessment of efficacy of ectoparasiticides against the myiasis causing parasites of ruminants. These guidelines specifically focus on larvicidal efficacy against myiasis causing flies. Information is provided on the selection of animals, dose determination and dose confirmation studies, field studies, record keeping and result interpretation. These guidelines advocate the use of pen facilities for dose determination and dose confirmation studies for defining therapeutic and persistent efficacy. These guidelines are also intended to assist investigators on how to conduct specific experiments, to provide specific information for registration authorities involved in the decision-making process, to assist in the approval and registration of new ectoparasiticides, and to facilitate the world-wide adoption of standard procedures.
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Affiliation(s)
- P A Holdsworth
- Avcare Limited, Locked Bag 916, Canberra, 2601 ACT, Australia.
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Vercruysse J, Rehbein S, Holdsworth PA, Letonja T, Peter RJ. World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guidelines for evaluating the efficacy of acaricides against (mange and itch) mites on ruminants. Vet Parasitol 2006; 136:55-66. [PMID: 16406329 DOI: 10.1016/j.vetpar.2005.11.009] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
These guidelines have been prepared to assist in the planning, conduct and interpretation of studies for the assessment of the efficacy of acaricides against mange and itch mites on ruminants. Information is provided on the selection of animals, dose determination, dose confirmation and field studies, record keeping and result interpretation. These guidelines also are intended to assist the investigators on how to conduct specific experiments, to provide specific information for registration authorities involved in the decision-making process, to assist in the approval and registration of new ectoparasiticides, and to facilitate the worldwide adoption of standard procedures.
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Affiliation(s)
- J Vercruysse
- Department of Virology, Parasitology & Immunology, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium.
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Holdsworth PA, Vercruysse J, Rehbein S, Peter RJ, Letonja T, Green P. World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guidelines for evaluating the efficacy of ectoparasiticides against biting lice, sucking lice and sheep keds on ruminants. Vet Parasitol 2006; 136:45-54. [PMID: 16359804 DOI: 10.1016/j.vetpar.2005.11.008] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
These guidelines have been prepared to assist in the design, implementation and interpretation of studies for the assessment of the efficacy of ectoparasiticides against biting and sucking lice and sheep keds on ruminants. Information is provided on the selection of animals, dose determination, dose confirmation and field studies, record keeping and result interpretation. These guidelines advocate the use of pen facilities for dose determination and dose confirmation studies for defining therapeutic and persistent efficacy. These guidelines are also intended to assist investigators on how to conduct specific experiments, to provide specific information for registration authorities involved in the decision making process, to assist in the approval and registration of new ectoparasiticides, and to facilitate the world-wide adoption of standard procedures.
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Affiliation(s)
- P A Holdsworth
- Avcare Limited, Locked Bag 916, Canberra, 2601 ACT, Australia.
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Holdsworth PA, Vercruysse J, Rehbein S, Peter RJ, De Bruin C, Letonja T, Green P. World Association for the Advancement of Veterinary Parasitology (W.A.A.V.P.) guidelines for evaluating the efficacy of ectoparasiticides against biting and nuisance flies on ruminants. Vet Parasitol 2006; 136:3-13. [PMID: 16359803 DOI: 10.1016/j.vetpar.2005.11.006] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
These guidelines have been prepared to assist in the planning, conduct and interpretation of studies for the assessment of the efficacy of ectoparasiticides (excluding repellents) against the biting and nuisance dipteran flies of ruminants. Information is provided on the selection of animals, dose determination and dose confirmation studies, field studies, record keeping and result interpretation. These guidelines advocate the use of pen facilities for dose determination and dose confirmation studies. These guidelines also are intended to assist investigators on how to conduct specific studies, to provide specific information for registration authorities involved in the decision-making process, to assist in the approval and registration of new ectoparasiticides, and to facilitate the worldwide adoption of standard procedures.
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Affiliation(s)
- P A Holdsworth
- Avcare Limited, Locked Bag 916, Canberra, 2601 ACT, Australia.
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Affiliation(s)
- S Rehbein
- Merial, Kathrinenhof Research Center, Walchenseestrasse 8-12, 83101 Rohrdorf, Germany
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36
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Abstract
A randomised block design study was conducted to evaluate the effects of mange on cattle. Twenty-four Simmentaler Fleckvieh bulls were formed into eight replicates of three bulls based on Day -56 body weight (288-414 kg). Within replicates bulls were randomly allocated to groups G1: uninfested control, G2: infested control or G3: infested, treated with 0.2mg ivermectin/kg (1% ivermectin injection; IVOMEC, Merial) on Day 0. The G2 and G3 bulls were infested with Sarcoptes/Chorioptes mites on Days -56 and -49. Feed consumption was recorded daily throughout the study (Days -56 to 56). Body weights were measured and serum samples collected. Mites were counted at bi-weekly intervals from Day -14 on. The carcasses of the bulls and the leather produced from their hides were evaluated. Differences between variables were declared significant if P</=0.05. All G2 and G3 bulls became infested. No Sarcoptes or Chorioptes mites were detected on the G3 bulls after Day 14 or Day 28, respectively, whereas G2 bulls maintained infestation throughout the study. From Days -42 to 0, anti-Sarcoptes antibody levels in the two infested groups increased linearly, while levels in the uninfested G1 remained near zero. From Day 14 to Day 56, antibody levels in G2 continued to increase and those in G3 decreased (P</=0.05). From Days -56 to 0, G1 had significantly greater mean weight gain (94.0 kg) than the infested G2 and G3 (76.1 and 75.9 kg). During Days 0-56, G3 gained significantly more weight (90.4 kg) than G2 (58.8 kg), while G1 gained 76.0 kg, not significantly different from either G2 or G3. During Days -56 to 0, the feed conversion efficiency (kg gain/kg feed) of the infested G2 and G3 was significantly lower than that of the uninfested G1; during the 56 days following treatment, feed conversion efficiency of G3 was significantly higher than that of G2, while the uninfested G1 was intermediate. Carcass weight of G2 was significantly lower than those of G1 and G3, which did not differ significantly. Carcass yield, rib eye area and weight of kidney fat of the uninfested G1 were significantly greater than those of G2 and G3. Weights of the adrenal glands, prescapular and precrural lymph nodes were significantly higher for the infested G2 than for the other two groups. Significantly less of leather area from the infested G2 was of usable quality than of the leathers from the uninfested G1 or the infested, treated G3, and the leathers from G2 showed significantly more severe gouging or etching than leathers from the two other groups.
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Affiliation(s)
- S Rehbein
- Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, 83101 Rohrdorf, Germany.
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Niemann B, Guttmann P, Rehbein S, Knöchel C. Concept and realization of the novel rotating condenser-monochromator at the Göttingen TXM at BESSY II. ACTA ACUST UNITED AC 2003. [DOI: 10.1051/jp4:200300079] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Wiesemann U, Thieme J, Guttmann P, Früke R, Rehbein S, Niemann B, Rudolph D, Schmahl G. First results of the new scanning transmission X-ray microscope at BESSY-II. ACTA ACUST UNITED AC 2003. [DOI: 10.1051/jp4:200300037] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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40
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Hertz HM, Johansson GA, Stollberg H, de Groot J, Hemberg O, Hotmberg A, Rehbein S, Jansson P, Eriksson F, Birch J. Table-top X-ray microscopy : Sources, optics and applications. ACTA ACUST UNITED AC 2003. [DOI: 10.1051/jp4:200300041] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
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Rehbein S, Visser M. Efficacy of ivermectin delivered via a controlled-release capsule against small lungworms (Protostrongylidae) in sheep. J Vet Med B Infect Dis Vet Public Health 2002; 49:313-6. [PMID: 12420864 DOI: 10.1046/j.1439-0450.2002.00576.x] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To evaluate the efficacy of an ivermectin controlled-release capsule (CRC), which delivers 1.6 mg ivermectin per day intraruminally for 100 days to sheep weighing 40-80 kg (IVOMEC Maximizer CR Capsule for adult sheep, Merial), against small lungworms two studies with 48 naturally infected adult female Merino Landrace sheep were conducted. The sheep were allocated by restricted randomization based on bodyweight to untreated controls or received an ivermectin CRC. Eight sheep per group were necropsied 35, 70 or 105 days post-treatment. Lungworms were recovered by dissection or peptic digestion of the lungs. Baermann/Wetzel technique was used for faecal lungworm larval counts at weekly intervals. The efficacy of treatment was 100% against Dictyocaulus filaria and Protostrongylus rufescens (P < 0.05) at each necropsy day. The efficacy against Protostrongylus brevispiculum, Cystocaulus ocreatus and Neostrongylus linearis increased from 35 to 105 days after administration of the CRC and was found to be 100% (P < 0.01), 96.6% (P < 0.01) or 99% (P < 0.01), respectively, at 105 days post-treatment. The reductions of Muellerius capillaris counts varied and were 96.2% (P < 0.05) at 70 days post-treatment and 44.6% (P > 0.1) at 105 days post-treatment. Faecal lungworm larvae disappeared nearly completely from at least 3 weeks after the ivermectin CRC administration for all protostrongylid species including M. capillaris so that pasture infectivity will be subsequently significantly reduced.
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Affiliation(s)
- S Rehbein
- Merial GmbH, Kathrinenhof Research Center, Rohrdorf, Germany
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Vercruysse J, Holdsworth P, Letonja T, Conder G, Hamamoto K, Okano K, Rehbein S. International harmonisation of anthelmintic efficacy guidelines (Part 2). Vet Parasitol 2002; 103:277-97. [PMID: 11777607 DOI: 10.1016/s0304-4017(01)00615-x] [Citation(s) in RCA: 52] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The "International Co-operation on Harmonisation of Technical Requirements for Registration of Veterinary Medicinal Products (VICH)" is an international programme of co-operation between regulatory authorities and the animal health industries of the European Union, Japan and the United States of America which aims to harmonise the technical requirements for the registration of veterinary medicinal products. Australia and New Zealand participate as active observers. The objective of this second paper is to present additional guidelines established by the Working Group on anthelmintic guidelines: (1) efficacy of anthelmintics: specific recommendations for equine (VICH GL15), (2) efficacy of anthelmintics: specific recommendations for porcine (VICH GL16), (3) efficacy of anthelmintics: specific recommendations for canine (VICH GL19), (4) efficacy of anthelmintics: specific recommendations for feline (VICH GL20) and (5) efficacy of anthelmintics: specific recommendations for poultry (VICH GL21). These guidelines do not consist of rigid stipulations, but make clear recommendations on the minimal standards needed. To the veterinary profession, livestock producers and animal owners, harmonisation should mean quicker access to safer and more effective veterinary anthelmintics. In general, products should be relatively more affordable because of the reduction in registration costs and efficient use of resources by the regulatory authorities.
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Affiliation(s)
- J Vercruysse
- Faculty of Veterinary Medicine, Department of Parasitology and Parasitic Diseases, Ghent University, Salisburylaan 133, B9820 Merelbeke, Belgium.
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Klei TR, Rehbein S, Visser M, Langholff WK, Chapman MR, French DD, Hanson P. Re-evaluation of ivermectin efficacy against equine gastrointestinal parasites. Vet Parasitol 2001; 98:315-20. [PMID: 11423189 DOI: 10.1016/s0304-4017(01)00436-8] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Two trials were conducted to confirm the efficacy of ivermectin paste against endoparasites of horses. In these trials, 20 ponies were treated with ivermectin oral paste at 200 mcg x kg body weight once on Day 0, and 20 ponies served as unmedicated controls. The animals carried naturally acquired parasite infections as confirmed by pretrial fecal examination. The animals were necropsied for worm recovery on Days 14, 15 or 16. Parasites recovered were identified to species. Horses treated with ivermectin had significantly (P<0.05) fewer (>99.0% reduction) adult small strongyles (Coronocyclus spp including C. coronatus, C. labiatus, C. labratus; Cyathostomum spp including C. catinatum, C. pateratum; Cylicocyclus spp including C. ashworthi, C. elongatus, C. insigne, C. leptostomum, C. nassatus, C. radiatus; Cylicodontophorus bicoronatus; Cylicostephanus spp including C. asymetricus, C. bidentatus, C. calicatus, C. goldi, C. longibursatus, C. minutus; Gyalocephalus capitatus; Parapoteriostomum spp including P. euproctus, P. mettami; Petrovinema poculatum; Poteriostomum spp including P. imparidentatum, P. ratzii) and adult large strongyles (Strongylus edentatus, S. vulgaris; Triodontophorus spp including T. brevicauda, T. serratus; Craterostomum acuticaudatum) than the controls. Ivermectin was also highly effective (94% to >99%, P<0.05-0.01) against Gasterophilus intestinalis larvae, Habronema spp., Oxyuris equi, Parascaris equorum. The data from these two trials confirm that ivermectin paste administered to horses orally at 200mcg x kg(-1) continues to be highly effective for treatment and control of a broad range of small and large strongyle species as well as other species of gastrointestinal parasites.
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Affiliation(s)
- T R Klei
- Department of Veterinary Science, Louisiana Agricultural Experiment Station, Louisiana State University-Agriculture Center, Baton Rouge, LA 70803, USA.
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Abstract
The species of flea infesting pets and hedgehogs in Germany were investigated through a survey of small animal practitioners throughout the country who were asked to collect specimens at their veterinary practices. A total of 625 veterinarians/veterinary practices responded and provided 2445 intact anti identifiable flea specimens. These fleas originated from 294 dogs (795 fleas), 334 cats (1152 fleas), 76 hedgehogs (481 fleas), five domestic rabbits (10 fleas), one golden hamster (four fleas) and one ferret (three fleas). Dogs were found to be infested with Archaeopsylla erinacei, Chaetopsylla globiceps, Ctenocephalides canis, Ctenocephalides felis, Hystrichopsylla talpae, Nosopsyllus fasciatus, Paraceras melis and Pulex irritans. From cats, Archaeopsylla erinacei, Ceratophyllus gallinae, Ceratophyllus garei, Ctenocephalides felis, Ctenophthalmus assimilis, Hystrichopsylla talpae, Monopsyllus sciurorum, Nosopsyllus fasciatus, Spilopsyllus cuniculi and Typhloceras poppei were collected. In both dogs and cats the most prevalent species were Ctenocephalides felis (78.9% and 91.6%, respectively) and Archaeopsylla erinacei (21.1% and 12.6%, respectively) followed by Ctenocephalides canis in dogs (5.8%) and Hystrichopsylla talpae in cats (1.2%). The fleas isolated from rabbits were Ctenocephalides felis, Hystrichopsylla talpae and Spilopsyllus cuniculi. Nosopsyllus fasciatus and Ctenocephalides felis were recovered from the golden hamster and the ferret, respectively. The hedgehogs were found to be infested with Archaeopsylla erinacei, Ceratophyllus gallinae and Ctenocephalides felis.
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Affiliation(s)
- M Visser
- Merial GmbH, Kathrinenhof Research Center, Rohrdorf, Germany
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Cramer LG, Pitt SR, Rehbein S, Gogolewski RP, Kunkle BN, Langhoff WK, Bond KG, Maciel AE. Persistent efficacy of topical eprinomectin against nematode parasites in cattle. Parasitol Res 2000; 86:944-6. [PMID: 11097305 DOI: 10.1007/s436-000-8011-z] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Six studies were conducted to evaluate the persistent efficacy of eprinomectin pour-on against experimental challenges with infective nematode larvae in calves. In each study, calves were randomly assigned to one untreated group and up to four test groups, which were treated with eprinomectin at 500 microg/kg body weight at weekly intervals before single bolus challenge. The calves were necropsied approximately 4 weeks after challenge infection for nematode recovery. Eprinomectin pour-on provided > or =90% efficacy against challenge with Haemonchus placei, Trichostrongylus axei and T. colubriformis at 21 days after treatment and against Cooperia oncophora, C. punctata, C. surnabada, Dictyocaulus viviparus, Nematodirus helvetianus, Oesophagostomum radiatum and Ostertagia ostertagi at 28 days after treatment.
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Rehbein S, Barth D, Visser M, Winter R, Cramer LG, Langholff WK. Effects of psoroptes ovis infection and its control with an ivermectin controlled-release capsule on growing sheep. 1. Evaluation of weight gain, feed consumption and carcass value. Vet Parasitol 2000; 91:107-18. [PMID: 10889363 DOI: 10.1016/s0304-4017(00)00245-4] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
To evaluate the prophylactic and therapeutic effects of an ivermectin controlled-release capsule (IVM-CRC) on the productivity of growing sheep infested with Psoroptes ovis 24 male and 24 female Merino landrace lambs, 5-6 months old and weighing 21.2-35.0 kg, were used. Sixteen replicates of three animals were formed based on sex and Day 0 body weight. Within each replicate animals were randomly allocated to one of three groups: untreated control; IVM-CRC on Day 0; IVM-CRC on Day 84. For treatment an IVM-CRC for sheep weighing 20-45 kg was used which is designed to deliver ivermectin at a minimum dose of 20 microg/kg per day for 100 days. The lambs were infested with 50-60 P. ovis mites each on Days 14 and 21. Mites in skin scrapings were counted on Days 70, 84, 98, 112 and 126. Body weight and feed consumption were measured every 2 weeks from Day 0 to 126. The animals were slaughtered on Day 127 and their carcasses evaluated. The IVM-CRC treatment on Day 0 prevented the establishment of P. ovis. All untreated lambs became infested. The lambs treated with an IVM-CRC on Day 84 became mite-free from Day 112 onwards. The lambs treated on Day 0 had significantly (p<0.05) greater body weight gain from Day 0 to 84 (13.9 kg) and Day 0 to 126 (20.9 kg) than the untreated controls (9.6 and 12.8 kg, respectively) and the sheep treated on Day 84 (8.4 and 14.9 kg, respectively). Feed consumption (Days 0-126) for sheep treated with the IVM-CRC on Day 0 was higher than for sheep treated on Day 84 (p<0.05) and for the untreated controls (p<0.1). The carcasses of sheep treated with the IVM-CRC on Day 0 had significantly (p<0.05) higher warm and cold weights, carcass yield, rib eye area and back fat thickness than the untreated control group and the sheep treated with the IVM-CRC on Day 84. The sheep treated with the ivermectin CRC on either Day 0 or 84 had significantly (p<0.05) better muscle scores and lower muscle pH 1h post-slaughter than the untreated controls. There was no significant (p>0.1) difference between warm and cold carcass weights, carcass yield and rib eye area between sheep treated on Day 84 and untreated controls.
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Affiliation(s)
- S Rehbein
- Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, D-83101, Rohrdorf, Germany.
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Rehbein S, Oertel H, Barth D, Visser M, Winter R, Cramer LG, Langholff WK. Effects of Psoroptes ovis infection and its control with an ivermectin controlled-release capsule on growing sheep. 2. Evaluation of wool production and leather value. Vet Parasitol 2000; 91:119-28. [PMID: 10889364 DOI: 10.1016/s0304-4017(00)00244-2] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
To evaluate the prophylactic and therapeutic effects of an ivermectin controlled-release capsule (IVM-CRC) on the productivity of growing sheep infested with Psoroptes ovis 24 male and 24 female Merino landrace lambs, 5-6 months old and weighing 21.2-35.0 kg, were used. Sixteen replicates of three animals were formed based on sex and Day 0 body weight. Within each replicate animals were randomly allocated to one of three groups: untreated control; IVM-CRC on Day 0; IVM-CRC on Day 84. For treatment an IVM-CRC for sheep weighing 20-45 kg was used which is designed to deliver ivermectin at a minimum dose of 20 microg/kg/day for 100 days. The lambs were infested with 50-60 P. ovis mites each on days 14 and 21. The animals were shorn on Day 126. After slaughter on Day 127 the quality of the leather produced from their skins was evaluated. The IVM-CRC treatment on Day 0 prevented the establishment of P. ovis. All untreated lambs became infested. The lambs treated with an IVM-CRC on Day 84 became mite-free from Day 112 onwards. The lambs which were treated on Day 0 had significantly (p<0.05) greater clean fleece weight (1.5 kg) and fleece yield (52.1%) than the untreated controls (0.9 kg and 34.1%, respectively) or than lambs treated on Day 84 (1.0 kg and 47.8%, respectively). Clean fleece weight and fleece yield were in the tendency (p=0.055) or significantly (p<0. 001) greater, respectively, for lambs treated on Day 84 than for the untreated controls. The chrome tanned dried crust leather of all untreated controls and six of the 16 lambs treated on Day 84 showed grain surface defects such as discolourations, indurations and coarse, pitted grain. The useful (defect-free) leather size was significantly (p<0.01) higher for the lambs treated on Day 0 (100%) than for the lambs treated on Day 84 (82.7%) and the untreated controls (7.8%). The physical testing revealed that the leather of sheep treated on Day 0 had significantly (p<0.05) higher thickness, elongation break and tear resistance than the leather of both untreated controls and sheep treated on Day 84. There were no significant differences in the physical characteristics of the leather of the untreated controls and the sheep treated on Day 84.
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Affiliation(s)
- S Rehbein
- Merial GmbH, Kathrinenhof Research Center, Walchenseestr. 8-12, D-83101, Rohrdorf, Germany.
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Rehbein S, Barth D, Visser M, Winter R, Langholff WK. Efficacy of an ivermectin controlled-release capsule against some rarer nematode parasites of sheep. Vet Parasitol 2000; 88:293-8. [PMID: 10714467 DOI: 10.1016/s0304-4017(99)00220-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
A controlled trial was conducted to evaluate the efficacy of the intraruminal ivermectin controlled-release capsule (CRC) (IVOMEC Maximizer CR Capsule for Sheep, Merial Ltd.) against induced incoming third-stage larvae and established adult infections with some rarer gastrointestinal nematode parasites of sheep. Twenty-one worm-free lambs were allocated by restricted randomisation based on body weight within sex to one of the following treatments: unmedicated control, ivermectin CRC given on Day 0 prior to induced infection, and ivermectin CRC given on Day 70 after establishment of induced infection. The ivermectin CRC delivers ivermectin at a minimum dose rate of 20 microg/kg/day for 100 days. Infections were induced by daily administration of third-stage larvae for five consecutive days. Nematodes were counted on Day 84, 14 days after treatment of established infection. The treatment with the ivermectin CRC prevented the establishment of Ostertagia leptospicularis, O. ostertagi, Bunostomum trigonocephalum, Cooperia oncophora, C. punctata, C. surnabada, Nematodirus helvetianus, N. roscidus and Strongyloides papillosus by >99% as compared with the untreated controls (p < 0.01). The administration of the ivermectin CRC reduced established adult infections of O. ostertagi, B. trigonocephalum, C. oncophora, C. punctata, C. surnabada, N. roscidus and S. papillosus by >99% (p < 0.01), and reduced established adult infections of O. leptospicularis and N. helvetianus by 96.5 and 98.4% (p < 0.01), respectively.
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Affiliation(s)
- S Rehbein
- Kathrinenhof Research Center, Merial GmbH, Rohrdorf-Lauterbach, Germany
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Affiliation(s)
- S Rehbein
- Kathrinenhof Research Center, Rohrdorf, Germany
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