Perfiles de los involucrados en el proceso de mentoría

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In C.gariepinus, 1 out of 4 fishes examined in weight group 200 – 299g were infected and 3 worms were recovered, giving a prevalence of 25.00 %, M.I.I of 3.00 and M.A of 0.75. On the other hand, 2 out of the 6 fishes examined in the weight group 400 – 499 g were infected and 7 worms were recovered, giving a prevalence of 33.33

%, M.I.I of 3.50 and M.A of 1.20. All the other weight groups (500-599g, 600-699g, 1000-1099g) examined were not infected. However, result of correlation analysis showed that there was an inverse significant relationship (- 0.501, P < 0.05) (Appendix 3) between fish weight and helminth infection implying that heavier fishes tended to have low prevalence. Likewise, the result of correlation analysis showed that there was no significant relationship (r = -.501, p = .311) (Appendix 4) between weight of C.

gariepinus and mean intensity of infection.

In C. obscura, 2 out of the 10 fishes examined in the weight group 0- 99g were infected and 4 worms were recovered, giving a prevalence of 20.00 %, M.I.I. of 2.00 and M.A of 0.40. Two (2) out of the 18 fishes examined in the weight group 100- 199g were infected and 6 worms were recovered, giving a prevalence of 11.11 %, M.I.I of 3.00 and M.A of 0.33. Also 2 out of the 19 fishes examined in the weight group 200 – 299g were infected and 8 worms were recovered, giving a prevalence of 10.53 %, M.I.Iof 4.00 and M.A of 0.42. Seven (7) out of the 10 fishes examined in the weight group 300 – 399g were infected and 29 worms were recovered, giving a prevalence of 70.00 %, M.I.I.of 4.14 and M.A. of 2.90. Four (4) out of the 11 fishes examined in the weight group 400 – 499g were infected and 30 worms were recovered, giving a prevalence of 36. 36 %, M. I. I.of 7.50 and M.A of 2.72. Two (2) out of the 3 fishes examined in the weight group 500 – 599g were infected and 8 worms were recovered,

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giving a prevalence of 66.67 %, M.I.I.of 4.00 and M.A of 2.70. All 2 fishes examined in the weight group 600 – 699g were infected and 34 worms were recovered, giving a prevalence of 100.00 %, M.I.I.of 17.00 and M.A of 17.00. It can be seen that the prevalence of infection rises and drops as the weight increases. However, the result of correlation analysis showed that there was significant relationship (0. 842, P< 0.05) (Appendix 3) in the weight and prevalence of infection in C. obsura. This implies that prevalence of infection increased with increasing fish weight.

In H. longifilis, only the lowest weight groups (400-499g) was found to be infected as all two fishes examined were infected giving a prevalence of 100.00 %, M.I.Iof 1.00 and M.A of 1.00. An inverse significant relationship (-0.775, P < 0.05) (Appendix 3) was observed in the correlation analysis. This implies that fish with less weight had higher prevalence. Correlation analysis between weight of H. longifilis and mean intensity of infection and mean abundance showed an inverse relationship, although it is not significant.

In H.niloticus, 8 out of 22 fishes examined in the weight group 0 – 99g were infected and 16 worms were recovered, giving a prevalence of 36.36 %, M.I.I of 2.00 and M.A of 0.73. Twenty – two (22) out of the 50 fishes examined in the weight group 200 – 299g were infected and 41 worms were recovered, giving a prevalence of 44.00

%, M.I.I of 1.90 and M.A of 0.82. Ten (10) out of the 24 fishes examined in the weight group 200 – 299g were infected and 41 worms recovered giving a prevalence of 41.67%, M.I.I of 4.10 and M.A of 1.71. Eight (8) out of the 15 fishes examined in the weight group 300 – 399g were infected and 13 worms were recovered giving a prevalence of 53.33 %, M.I.I of 1.63 and M.A of 0.90. Five (5) out of the 8 fishes

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examined in the weight group 400 – 499g were infected and 57 worms were recovered giving a prevalence of 62.50 %, M.I.I of 11.40 and M.A of 7.13. All four fishes examined in the weight group 500-599g were infected giving a prevalence of 100.00 %, M.I.I. of 8.30 and M.A of 8.30. Seventeen (17) out of the 18 fishes examined in the weight group 600 – 699g were infected and 220 worms were recovered giving a prevalence of 94.45 %, M.I.I of 12.94 and M.A. of 12.22. All two fishes examined in weight group 1000 – 1099g and 1100- 1199g were all infected giving a prevalence of 100.00% each. The prevalence of helminth infection increased with increasing host weight although it declined in weight group 200- 299g and 600- 699g. However, correlation analysis revealed that there was no significant relationship (0.144, P < 0.05) (Appendix 3) between fish weight and prevalence of infection. This implied that prevalence of helminth infection in H.niloticus had nothing to do with weight of the fish. Similarly, correlation analysis revealed that there was no significant relationship between weight of H. niloticus and mean intensity of infection and mean abundance.

In M.electricus, 4 out of the 6 fishes examined in the weight group 0 – 99g were infected and 24 worms were recovered, giving a prevalence of 66.67 %, M.I.I of 6.00 and M.A of 4.00. All four fishes examined in the weight group 100 – 199g were infected and 8 worms were recovered, giving a prevalence of 100.00 %, M.I.I of 2.00 and M.A of 2.00. Two (2) out of the 12 fishes examined in the weight group 200 – 299g were infected and 16 worms were recovered, giving a prevalence of 16.67 %, M.I.I of 8.00 and M.A of 1.33. Six (6) out of the 8 fishes examined in the weight group 300 – 399g were infected and 27 worms were recovered, giving a prevalence of 75.00 %, M.I.I of 4.50 and M.A of 3.38. All two fishes examined in the weight group 400 – 499g

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were infected and 37 worms were recovered, giving a prevalence of 100.00 %, M.I.I) of 18.50 and M.A of 18.50. Result of correlation analysis showed that there was no significant relationship (0.193, P < 0.05) between fish weight and helminth infection in M.electricus. Similarly, correlation analysis showed that there was no significant relationship (r = 0.660, p = 0.225) between fish weight and mean intensity of infection and between fish weight and mean abundance (0.653, p = 0.232) (Appendix 4).

In Synodontis batensoda, prevalence of infection also increased with increasing host weight (0-99g and 100-199g) upto a certain limit after which it decreased as seen in weight group 200 – 299g and 300-399g, although the number of parasites/helminths recovered increased with increasing host weight. The highest prevalence of infection (66.67 %) occurred in weight group 100 – 199g. Correlation analysis revealed that there was an inverse significant relationship (- 0.434, P < 0.05) (Appendix 3) between fish weight and helminth infection in S.batensoda. This implies that fish with less weight had higher prevalence of infection. Also, correlation analysis revealed that there was no significant relationship between weight of S. batensoda and mean intensity of infection (r = -0.775, p = 0.225) and mean abundance (r = -0.183, p = 0.817) (Appendix 4) but the nature of the relationship that exists is an inverse one.

In Synodontis eupterus, 2 fishes in weight group 0 – 99g were infected with 4 worms recovered, giving a prevalence of 100.00 %, M.I.I of 2.00 and M.A of 2.00. Two (2) out of 18 fishes examined in weight group 100 – 199g were infected with 2 worms recovered, giving a prevalence of 11.11 %, M.I.I of 1.00 and M.A of 0.11. The other weight groups examined namely 300-399g, 400 – 499g and 500 – 599g had a prevalence of 37.50 %, 25.00 % and 100.00 % respectively except weight group

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299g which was not infected. It can be seen that prevalence of infection increased with increasing fish weight up to a certain limit, after which it decreased (table 3), although the helminths recovered were seen to increase as the host weight increased apart from weight group 0-99g. Correlation analysis also revealed that there was no significant relationship (r = 0.096, p < 0.05) (Appendix 3) between fish weight and helminth infection in S. eupterus, although there was a significant relationship (r = 0.822, p = 0.01) (Appendix 4) between weight of S. eupterus and mean intensity of infection but none between weight of S. eupterus and mean abundance. This implies that the mean intensity of infection increased with increasing weight.

In C. lazera, P. annectens, S. mystus and C. nigrodigitatus, only one weight classin each species was found to be infected. For C lazera, all 2 fishes examined in the weight group 200 – 299g were infected and 6 worms were recovered, giving a prevalence of 100.00 %, M.I.I of 3.00 and M.A.of 3.00. Two (2) out of 15 P. annectens examined in the weight group 200 – 299g were infected and 4 worms were recovered giving a prevalence of 13.33 %, M.I.I.of 2.00 and M.A.of 0.30. For S. mystus, 2 out of the 38 fishes examined in the weight group 0 – 99g were infected and 2 worms recovered, giving a prevalence of 5.26 %, M.I.I of 1.00 and M.A of 0.10. Likewise 2 out of the 6 C. nigrodigitatus examined in the weight group 0-99g were infected and 2 worms were recovered, giving a prevalence of 33.33 %, M.I.I.of 1 and M.A. of 0.3.

Correlation analysis was not done because only one weight group on each of the fish species was infected.

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Table 3: Relationship between fish weight and helminth infection.

Fish species Fish Weight (g) N.E N.I P (%) N.P.R M.I.I M.A A. Occidentalis 0 – 99 24 2 8.33 16 8.00 0.70

100 – 199 8 6 75.00 32 5.33 4.00

C. anguillaris 0 – 99 4 0 0.00 0 0.00 0.00

100 – 199 6 2 33.33 2 1.00 0.33

200 – 299 5 2 40.00 2 1.00 0.40

C. gariepinus 200 – 299 4 1 25.00 3 3.00 0.75

300 – 399 2 0 0.00 0 0.00 0.00

400 – 499 6 2 33.33 7 3.50 1.20

500 – 599 2 0 0.00 0 0.00 0.00

600 - 699 2 0 0.00 0 0.00 0.00

1000 - 1099 15 0 0.00 0 0.00 0.00

C.lazera 0 - 99 6 0 0.00 0 0.00 0.00

100 - 199 2 0 0.00 0 0.00 0.00

200 - 299 2 2 100.00 6 3.00 3.00

300 - 399 - - - -

400 - 499 2 0 0.00 0 0.00 0.00

C. obscura 0 - 99 10 2 20.00 4 2.00 0.40

100 - 199 18 2 11.11 6 3.00 0.33

200 - 299 19 2 10.53 8 4.00 0.42

300 - 399 10 7 70.00 29 4.14 2.90

400 - 499 11 4 36.36 30 7.50 2.72

500 - 599 3 2 66.67 8 4.00 2.70

600 - 699 2 2 100.00 34 17.00 17.00

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C.nigrodigitatus 0 - 99 6 2 33.33 2 1.00 0.33

100 - 199 0 0 0.00 0 0.00 0.00

200 - 299 20 0 0.00 0 0.00 0.00

300 - 399 3 0 0.00 0 0.00 0.00

400 - 499 2 0 0.00 0 0.00 0.00

500 - 599 3 0 0.00 0 0.00 0.00

700- 799 2 0 0.00 0 0.00 0.00

800 - 899 2 0 0.00 0 0.00 0.00

1800 - 1899 1 0 0.00 0 0.00 0.00

H. longifilis 400 – 499 2 2 100.00 2 1.00 1.00

500 – 599 - - - -

600 – 699 6 0 0.00 0 0.00 0.00

900-999 4 0 0.00 0 0.00 0.00

H. niloticus 0 -99 22 8 36.36 16 2.00 0.73

100 – 199 50 22 44.00 41 1.90 0.82 200 – 299 24 10 41.67 41 4.10 1.71

300 – 399 15 8 53.33 13 1.63 0.90

400 – 499 8 5 62.50 57 11.40 7.13

500 – 599 4 4 100.00 33 8.30 8.30

600 – 699 18 17 94.45 220 12.94 12.22

700 – 799 2 0 0 0 0.00 0.00

800 – 899 - - - -

900 – 999 - - - -

1000 – 1099 2 2 100.00 4 2.00 2.00 1100 – 1199 2 2 100.00 27 13.50 13.50 M. electricus 0 – 99 6 4 66.67 24 6.00 4.00

100 – 199 4 4 100.00 8 2.00 2.00

200 – 299 12 2 16.67 16 8.00 1.33

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300 – 399 8 6 75.00 27 4.50 3.38

400 – 499 2 2 100.00 37 18.50 18.50

P. annectens 0 - 99 0 0 0.00 0 0.00 0.00

100 - 199 16 0 0.00 0 0.00 0.00

200 - 299 15 2 13.33 4 2.00 0.30

300 - 399 3 0 0.00 0 0.00 0.00

400 - 499 3 0 0.00 0 0.00 0.00

500- 599 2 0 0.00 0 0.00 0.00

600- 699 3 0 0.00 0 0.00 0.00

700- 799 1 0 0.00 0 0.00 0.00

1400- 1499 1 0 0.00 0 0.00 0.00

S. batensoda 0 – 99 18 3 16.67 16 5.33 0.90

100 – 199 6 4 66.67 20 5.00 3.33

200 – 299 34 7 20.59 35 5.00 1.03

300 – 399 2 0 0.00 0 0.00 0.00

S. eupterus 0 – 99 2 2 100.00 4 2.00 2.00

100 – 199 18 2 11.11 2 1.00 0.11

200 – 299 3 0 0.00 0 0.00 0.00

300 – 399 8 3 37.5 10 3.30 1.30

400 – 499 8 2 25.00 10 5.00 1.30

500 – 599 4 4 100.00 31 7.80 7.80

S. mystus 0- 99 38 2 5.26 2 1.00 0.10

100- 199 0 0 0.00 0 0.00 0.00

KEY = N.E – Number Examined ; N.I. – Number Infected; NPR – Number of Parasite

Recovered; P – Prevalence; MII – Mean Intensity of Infection, MA – Mean Abundance

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