COPYRIGHT AND CITATION CONSIDERATIONS FOR THIS THESIS/ DISSERTATION o Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use. o NonCommercial — You may not use the material for commercial purposes. o ShareAlike — If you remix, transform, or build upon the material, you must distribute your contributions under the same license as the original. How to cite this thesis Surname, Initial(s). (2012) Title of the thesis or dissertation. PhD. (Chemistry)/ M.Sc. (Physics)/ M.A. (Philosophy)/M.Com. (Finance) etc. [Unpublished]: University of Johannesburg. Retrieved from: https://ujdigispace.uj.ac.za (Accessed: Date). E\:)ro Rouj ASPECTS OF THE MORPHOLOGY AND THE ECOLOGY OF A PARADIPLOZOON SPECIES FROM BARBUS AENEUS IN THE VAAL DAM, SOUTH AFRICA LOUISE ERICA LE ROUX Supervisor: Prof. A. Avenant-Oldewage Co-supervisor: Prof. S.N. Mashego A dissertation submitted in partial fulfilment ofthe requirements for the degree of Master ofScience in Zoology in the Faculty ofScience ofthe Rand Afrikaans University Johannesburg, May 2001 ABSTRACT Only a few species of the family Diplozoidae have previously been described from Africa, from various Labeo and Barbus species. An investigation was undertaken respectively in the Vaal Dam and Vaal River Barrage in the Vaal River system, South Africa to determine aspects of the morphology, taxonomy and ecology of specimens of this family collected from the gills of Barbus aeneus. Various fish species, namely B. aeneus, Barbus kimberleyensis, Labeo capensis, Labeo umbratus, Cyprinus carpio, Clarias gariepinus and Micropterus salmoides, were collected with the aid of gill nets. The fish were killed and the length, weight and sex determined. The gills were removed from the left and right gill chambers, placed in separate, marked petri dishes and covered with water from the dam. Gills (from first to fourth pair) were examined with the aid ofa dissection microscope. The position ofattachment and the region on the gill namely dorsal, median or ventral, was noted. Parasites were removed, fixed between a cover slip and glass slide in steaming hot aceto-formaldehyde alcohol and preserved in 70 % ethanol. A morphological study was undertaken. Results of a Scanning Electron Microscopy study illustrated the following external characteristics namely a round opisthohaptor with four pairs of clamps, while study of whole mounts revealed larval hooks, a round-ended intestine and eggs without filaments. Graphic reconstruction of serial sections of the reproductive system of parasites embedded in resin revealed that the vas deferens of one individual opens into the common vitelline duct of the other. Parasites were identified as belonging to the genus Paradiplozoon. The morphological characteristics, namely the round opisthohaptor, intestine with rounded ending, egg without filament and morphological measurements, of various structures (for example, total body length) that differ from other species of this genus, led to the establishment of a new species, that is, P. alwinii. A relatively low prevalence, abundance and mean intensity of P. alwinii was recorded from'B. aeneus for II which it is highly host specific. P. alwinii showed no preference for either gender, age or size group ofthe host. Little is known about the host behaviour, especially feeding habits and whether this increases chances of infestation. No definite conclusions could thus be made. The influence of the habitat on the occurrence could not be determined, but it was clear that seasonal change and resultant temperature variations influence the occurrence ofP. alwinii. It was expected that water quality would influence prevalence, abundance and intensity of P. alwinii, but sample size was insufficient to draw scientifically valid conclusions. With regard to preferred attachment sites the adults were found to occur mostly on the first (anterior) and fourth (posterior) gill arches, mostly in the median regions. Larvae appeared to be evenly dispersed over all four gill pairs, occurring more often in the ventral regions, however insufficient larval sample sizes hindered any definite conclusions. KEYWORDS: Platyhelminthes Monogenea Diplozoidae Vaal River Paradiplozoon alwinii Barbus aeneus Fish parasite Ectoparasite iii OPSOMMING Slegs 'n paar spesies van die familie Diplozoidae is tot op hede uit Afrika vanaf verskeie Labeo en Barbus spesies beskryf. 'n Ondersoek is onderskeidelik in die Vaaldam en Vaalrivier Barrage in die Vaalriviersisteem, Suid-Afrika geloods om aspekte van die morfologie, taksonomie en ekologie van verteenwoordigers van die familie, wat vanaf die kieue van Barbus aeneus versamel is, te bepaal. 'n Verskeidenheid visspesies, naamlik B. aeneus, Barbus kimberleyensis, Labeo capensis, Labeo umbratus, Cyprinus carpio, Clarias gariepinus en Micropterus salmoides, is met behulp van kieunette versamel. Die visse is gedood en die lengte, massa en geslag is bepaal. Die kieue is vanuit die linker- en regterkieukamers verwyder, in apart gemerkte petri-bakkies geplaas en met water vanuit die dam bedek. Kieue (vanaf die eerste tot vierde paar) is met behulp van 'n disseksiemikroskoop bestudeer. Die vashegtingsposisie en area op die kieu naamlik dorsaal, mediaan ofventraaI, is genoteer. Parasiete is verwyder, tussen 'n dekgasie en mikroskoopplaatjie in stomende asetoformaldehiedalkohol gefikseer en in 70 % etanol gepreserveer. 'n Morfologiese studie is onderneem. Resultate van 'n Skandeer elektronmikroskopiese studie het die volgende uitwendige eienskappe geillustreer naamlik 'n geronde opisthaptor met vier pare klampe. Die studie van totaalpreparate het interne strukture, naamlik larwale hake, rond eindigende intestinum en eiers sonder filamente uitgewys. Grafiese rekonstruksie van seriesnee van die voortplantingstelsel van parasiete wat in hars ingebed was, het onthul dat die vas deferens van een individu in die gemeenskaplike vitelienbuis van die ander individu open. Parasiete is geidentifiseer as behorend tot die genus Paradiplozoon. Die morfologiese eienskappe, naamlik die ronde opisthaptor, intestinum met geronde einde, eier sonder filament en morfologiese afmetings van verskeie strukture (onder andere totale liggaamslengte) wat verskil van ander spesies in hierdie genus, het gelei tot die beskrywing van 'n nuwe spesie, naamlik P. alwinii. 'n Relatiewe lae besmettingsmoontlikheid, IV persentasiebesmetting en gemiddelde besmettingsintensiteit van P. alwinii vanaf B. aeneus, waarvoor dit hoogs gasheerspesifiek is, is genoteer. P. alwinii het geen voorkeur vir geslag, ouderdom of lengte groep van die gasheer getoon nie. Min is bekend oor die gasheer se gedrag, veral voedingsgewoontes, en of dit die kanse van besmetting verhoog. Geen definitiewe gevolgtrekkings kan dus gemaak word nie. Die invloed van die habitat op die verspreiding kon nie bepaal word nie, maar dit was duidelik dat seisoenale veranderinge en gevolglike temperatuurvariasies die aanwesigheid van P. alwinii bemvloed. Dit was verwag dat waterkwaliteit die besmettingsmoontlikheid, persentasiebesmetting en gemiddelde besmettingsintensiteit van P. alwinii sou beinvloed, maar steekproefgrootte was onvoldoende om wetenskaplik geldige gevolgtrekkings te maak. Met betrekking tot voorkeurvashegtingsareas is gevind dat volwassenes meestal aanwesig is op die eerste (anterior) en vierde (posterior) kieue, meestal in die mediaan areas. Dit het geblyk dat larwes eweredig versprei is oor al vier pare kieue, meer algemeen in die ventrale areas, maar onvoldoende larwale steekproefgroottes verhoed enige definitiewe gevolgtrekkings. SLEUTELWOORDE: Platyhelminthes Monogenea Diplozoidae Vaal River Paradiplozoon alwinii Barbus aeneus Fish parasite Ectoparasite v DECLARATION I declare that this report is my own original work. It is being submitted in partial fulfilment of the requirements for the degree of Master of Science in the Faculty of Science of the Rand Afrikaans University, Johannesburg, South Africa. It has not been submitted before for any other degree or examination in any other university. Louise Erica Ie ROllX VI DEDICATION This dissertation is dedicated to my Mother, Annemarie van Loggerenberg, whose lifelong motto has been "perseverance is the only key to success" VII ACKNOWLEDGEMENTS With sincere gratitude to: • The Creator of man and Paradiplozoon alwinii, both perfect III their complexities. • My husband, family and friends for their support throughout this study. • My supervisor, Professor Avenant-Oldewage for her guidance and ongoing encouragement and financial support. • Professor Mashego of RAU's Zoology Department for reading my dissertation and making recommendations. • Hester Roets of RAU's Graphics Department for graphic reproductions ofthe figures contained in this document. • Professor Swanepoel of RAU's Zoology Department for his translations ofKhotenovsky's (1981 and 1985) keys to the Diplozoidae family. • Mrs Edie Lutsch of RAU's Zoology Department for guidance III producing histological sections as well as staining. • The National Research Foundation, Pretoria, for their financial support for this project. • Jeannette Menasce for proof-reading this document and for assisting me with the layout. viii CONTENTS ABSTRACT II KEYWORDS: iii OPSOMMING IV SLEUTELWOORDE: v DECLARATION ~ VI DEDICATION VII ACKNOWLEDGEMENTS VIII CONTENTS IX LIST OF FIGURES XII LIST OF TABLES XIII ABBREVIATIONS XIV CHAPTER 1: INTRODUCTION