Parasite fauna of Rastrineobola argentea (Pellegrin 1904) with reference to Ligula intestinalis in the Kenyan part of Lake Victoria
Ogwai, C. (1997). Parasite fauna of Rastrineobola argentea (Pellegrin 1904) with reference to Ligula intestinalis in the Kenyan part of Lake Victoria. MSc Thesis. KUL: Leuven. 43 pp. |
Available in | Author | | Document type: Dissertation
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Abstract | Investigations into the parasite ecology of the Rastrineobola argentea and the parasitic tape worm Ligula intestinalis were carried out between July 1996 and October 1996 in the Kenyan part of lake Victoria (Nyanza gulf). Data collected from the gulf since 1993 have also been reanalized to see the infestation trends within the 4 year period. Some 2000 animals were carefully examined for the presence of parasites. Comparison of infestation rates in the transect, within and between stations and fluctuations in the infestation loads between seasons was made. Parasite loads and infestation rates tended to increase towards the open lake as well as the standard length of the fishes. Maximum parasite load was noted during the wet season and was 19 parasites in one specimen. These multiple infestations tended to register low total weight, and length compared to their counterparts in 'one only' infestations. Maximum parasite length was 160mm, while the minimum was 2mm. The infected fish appeared to prefer swimming closer to the water surface than their healthy counterparts that were bottom dwelling in the daytime samples. Significant differences were observed in fat, protein, and ash content between the infected and the non infected fish. There was however no significant difference registered in the moisture content of the two groups. Mean percentage protein for parasitised and unparasitised samples respectively were 15.54±0.52, 17.19±0.67, for fats, 4.67±0.81, 8.41±0.75, ash, 12.45±1.22, 9.52±0.78, and moisture 70.80±4.64, 71.40±1.31. |
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