Figure 1
(A) C. zillii, (B) O. aureus, (C) O. niloticus; Al-Zubaidiyah, Iraq.
Figure 2
Sampling locations of three cichlid species.
Figure 3
Influence of fixative, freezing, and preservative on the physical dimensions of C. zillii. (A) mixing 10% formalin with tap water; (B) mixing 10% formalin and distilled water mixture; (C) mixing 5% formalin with tap water; (D) mixing 5% formalin with distilled water. HL, head length; SL, standard length, TL, total length.
Figure 4
Influence of fixative, freezing, and preservative on the physical dimensions of C. zillii. (E) mixing 70% ethanol with tap water; (F) mixing 70% ethanol with distilled water; (G) freezing. HL, head length; SL, standard length, TL, total length.
Figure 5
Influence of fixative, freezing, and preservative on the physical dimensions of O. aureus. (A) mixing 10% formalin with tap water; (B) mixing of 10% formalin and distilled water mixture; (C) mixing 5% formalin with tap water; (D) mixing 5% formalin with distilled water. HL, head length; SL, standard length, TL, total length.
Figure 6
Influence of fixative, freezing, and preservative on the physical dimensions of O. aureus. (E) mixing 70% ethanol with tap water; (F) mixing 70% ethanol with distilled water; (G) freezing. HL, head length; SL, standard length, TL, total length.
Figure 7
Influence of fixative, freezing, and preservative on the physical dimensions of O. niloticus. (A) mixing 10% formalin with tap water; (B) mixing of 10% formalin and distilled water mixture; (C) mixing 5% formalin with tap water; (D) mixing 5% formalin with distilled water. HL, head length; SL, standard length, TL, total length.
Figure 8
Influence of fixative, freezing, and preservative on the physical dimensions of O. niloticus. (E) mixing 70% ethanol with tap water; (F) mixing 70% ethanol with distilled water; (G) freezing. HL, head length; SL, standard length, TL, total length.
Table 1
Least-squares regression equations for the TL, SL, and HL of C. zillii, O. aureus, and O. niloticus obtained from the Tigris river in Al-Zubaidiyah City, Iraq, using various fixatives, preservatives, and freezing methods
| Morphometric features of species | fixative, preservative, Freezing | Equation of conversion |
|---|---|---|
| C. zillii | ||
| TL | A mixture of 10% formalin and tap water | LFT = 1.001 LTPTW + 0.432 |
| Mixture of 10% formalin and distilled water | LFT = 1.005 LTPDW + 0.229 | |
| Mixture of 70% ethanol and tap water | LFT = 1.015 LTPETW + 0.296 | |
| Mixture of 70% ethanol and distilled water | LFT = 1.012 LTPEDW + 0.332 | |
| Freezing | LFT = 1.075 LTPF + 0.663 | |
| SL | A mixture of 10% formalin and tap water | LFS = 1.009 LSPTW + 0.291 |
| Mixture of 10% formalin and distilled water | LFS = 1.007 LSPDW + 0.670 | |
| Mixture of 70% ethanol and tap water | LFS = 1.024 LSPETW + 0.852 | |
| Mixture of 70% ethanol and distilled water | LFS = 1.026 LSPEDW + 0.531 | |
| Freezing | LFS = 1.032 LSPF + 0.763 | |
| HL | A mixture of 10% formalin and tap water | LFH = 1.033 LHPTW + 0.611 |
| Mixture of 10% formalin and distilled water | LFH = 1.096 LHPDW + 0.787 | |
| Mixture of 70% ethanol and tap water | LFH = 1.094 LHPETW + 0.262 | |
| Mixture of 70% ethanol and distilled water | LFH = 1.091 LHPEDW + 0.963 | |
| Freezing | LFH = 1.097 LHPF + 0.178 | |
| O. aureus | ||
| TL | A mixture of 10% formalin and tap water | LFT = 1.018 LTPTW + 0.135 |
| Mixture of 10% formalin and distilled water | LFT = 1.017 LTPDW + 0.118 | |
| Mixture of 70% ethanol and tap water | LFT = 1.012 LTPETW + 0.210 | |
| Mixture of 70% ethanol and distilled water | LFT = 1.012 LTPEDW + 0.349 | |
| Freezing | LFT = 1.033 LTPF + 0.620 | |
| SL | A mixture of 10% formalin and tap water | LFS = 1.013 LSPTW + 0.288 |
| Mixture of 10% formalin and distilled water | LFS = 1.010 LSPDW + 0.562 | |
| Mixture of 70% ethanol and tap water | LFS = 1.020 LSPETW + 0.238 | |
| Mixture of 70% ethanol and distilled water | LFS = 1.020 LSPEDW + 0.361 | |
| Freezing | LFS = 1.040 LSPF + 0.872 | |
| HL | A mixture of 10% formalin and tap water | LFH = 1.042 LHPTW + 0.875 |
| Mixture of 10% formalin and distilled water | LFH = 1.040 LHPDW + 0.983 | |
| Mixture of 70% ethanol and tap water | LFH = 1.083 LHPETW + 0.297 | |
| Mixture of 70% ethanol and distilled water | LFH = 1.082 LHPEDW + 0.360 | |
| Freezing | FH = 1.037 LHPF + 0.194 | |
| O. niloticus | ||
| TL | A mixture of 10% formalin and tap water | LFT = 1.016 LTPTW + 0.133 |
| Mixture of 10% formalin and distilled water | LFT = 1.015 LTPDW + 0.116 | |
| Mixture of 70% ethanol and tap water | LFT = 1.014 LTPETW + 0.212 | |
| Mixture of 70% ethanol and distilled water | LFT = 1.010 LTPEDW + 0.347 | |
| Freezing | LFT = 1.035 LTPF + 0.622 | |
| SL | A mixture of 10% formalin and tap water | LFS = 1.011 LSPTW + 0.285 |
| Mixture of 10% formalin and distilled water | LFS = 1.011 LSPDW + 0.563 | |
| Mixture of 70% ethanol and tap water | LFS = 1.019 LSPETW + 0.237 | |
| Mixture of 70% ethanol and distilled water | LFS = 1.022 LSPEDW + 0.363 | |
| Freezing | LFS = 1.039 LSPF + 0.871 | |
| HL | A mixture of 10% formalin and tap water | LFH = 1.044 LHPTW + 0.877 |
| Mixture of 10% formalin and distilled water | LFH = 1.041 LHPDW + 0.984 | |
| Mixture of 70% ethanol and tap water | LFH = 1.081 LHPETW + 0.299 | |
| Mixture of 70% ethanol and distilled water | LFH = 1.084 LHPEDW + 0.361 | |
| Freezing | FH = 1.038 LHPF + 0.196 | |
[i] LFH represents HL when fresh; LFPS indicates SL preserved by freezing; LFT is TL when fresh; LFS denotes SL when fresh; LHPF is HL preserved by freezing; LHPDW refers to HL preserved in formalin-distilled water; LHPEDW is HL preserved in ethanol-distilled water; LHPETW stands for HL preserved in ethanol-tap water; LHPTW is HL preserved in formalin-tap water; LSPDW indicates SL preserved in formalin-distilled water; LSPEDW is SL preserved in ethanol-distilled water; LSPETW refers to SL preserved in ethanol-tap water; LSPTW is SL preserved in formalin-tap water; LTPF denotes TL preserved by freezing; LTPDW is TL preserved in formalin-distilled water; LTPEDW stands for TL preserved in ethanol-distilled water; LTPETW is TL preserved in ethanol-tap water; LTPTW refers to TL preserved in formalin-tap water.