Morphological heterogeneity and population differentiation in the green chromid Etroplus suratensis (Pisces: Cichlidae) in Sri Lanka

Morphological variation of the euryhaline cichlid fish Etroplus suratensis (Bloch) from six geographically apart estuarine localities along the southern and western coasts of Sri Lanka was studied. Significant heterogeneity in morphology of the cichlid were found with respect to nine morphometric characters (n=218). Fish of Nilwala estuary and Garanduwa lagoon were not significantly different in morphology, yet they show discernible differences from the other four samples (Kahanda lagoon, Chilaw lagoon, Walawe estuary and Koggala lagoon) with respect to the most of the studied characters. Concordant results were found by multivariate analysis of the sizecorrected morphological data as well. Three functions were significant in discriminating the populations of which the first two functions accounted for 95% of the covariance (CV1 85.4 % and CV2 9.7%). The function with the greatest discriminatory power (CV1) can clearly separate samples of Nilwala estuary (L5) and Garanduwa lagoon (L6) from the rest of the samples, while the magnitude of the discrimination between the latter samples is much smaller. Classification functions could correctly classify an average of 65.7% of the individuals into their respective a priori population units. No evidence was found for isolation-by-distance model. The results suggest that E. suratensis populations in some of the studied estuarine localities maintain significant morphological heterogeneity, and the morphological variation can be used to differentiate some of these populations

Morphometric and isozyme confirmation for species level divergence between Puntius dorsalis (Pisces: Cyprinidae) and its presumed red-fin variety in Sri Lanka

Isozyme and morphological variation provide evidence for species-level divergence between Puntius dorsalis and the red-fin variety, presumed to be conspecific to P. dorsalis, thus warrant the recognition of the P. dorsalis like red-fin variety in Sri Lanka as a separate phylogenetic taxon, hitherto undescribed. Idh, Mdh-1 and Pgm isozymes display fixed allelic differences between the two varieties indicating reproductive isolation and species-level divergence. In addition to the presence of 3½ transverse scale rows above lateral line (vs. 4½ in P. dorsalis) which is a distinctive autaphomorphy, the snout is significantly longer in the red-fin variety (30.3%HL vs. 22.6%HL of P. dorsalis)

Chronic Kidney Disease of Unknown Etiology (CKDu) in Sri Lanka: Hematological Changes and Pro-Inflammation Suggest Likely Predictors of Advance Disease, as Renal Outcomes Show Prevalent Normoalbuminuria

CKDu needs to be characterized in fundamental areas to improve etiological understanding and disease management. In a cross-sectional study, blood cell profile and plasma inflammatory cytokines were followed by automated analysis and sandwich ELISA, respectively. Disease development stages and proteinuria were ascertained by eGFR and UACR. Comparison among control and stages (ANOVA/Dunnett’s MRT) revealed time-specific changes (p < 0.05), including decreased erythrocytes (G5) and hematocrit (G5), and increased MCHC (G3b, G4), MCV (G5), and MCH (G5). CKDu decreased (p < 0.05) lymphocytes (G3b, G4, G5), monocytes (G3b), MPV (G3b, G4, G5), and plateletcrit (G3b, G4), and increased basophils (G3a, G3b, G4), N/L (G4) and PLR (G4–G5). MCHC and aforesaid leukocyte variables were in correlation (rho > ±0.03, p < 0.05, Pearson’s test) with disease development. MCP-1 and IL-6 spiked (p > 0.05) at G3b. Multivariate analyses confirmed that MCP-1, lymphocytes, and BMI were related to renal dysfunction, pointing to inflammation, compromised immunity, and muscle wasting as CKDu effects. Nonproteinuric CKDu was prevalent (23.2–35.6% of total CKDu) with (p < 0.05) elevated basophils (G3a), N/L (G4), and depleted lymphocytes (G4). In both forms, G1–G2 were unaffected, and the earliest change was G3a basophils. Results suggest that MCP-1, lymphocyte count, N/L, and PLR may verify the stage and predict impending ESRD in advance proteinuric CKDu

Metals and Metallothionein Expression in Relation to Progression of Chronic Kidney Disease of Unknown Etiology (CKDu) in Sri Lanka

Chronic kidney disease of unknown etiology was investigated for metal relations in an endemic area by a cross-sectional study with CKD stages G1, G2, G3a, G3b, G4, G5 (ESRD), and endemic and nonendemic controls (EC and NEC) as groups. Subjects with the medical diagnosis were classified into groups by eGFR (SCr, CKD-EPI) and UACR of the study. It determined 24 metals/metalloids in plasma (ICPMS) and metallothionein (MT) mRNA in blood (RT-PCR). MT1A at G3b and MT2A throughout G2–G5 showed increased transcription compared to NEC (ANOVA, p < 0.01). Both MT1A and MT2A remained metal-responsive as associations emerged between MT2A and human MT inducer Cr (in EC: r = 0.54, p < 0.05, n = 14), and between MT1A and MT2A (in EC pooled with G1–G5: r = 0.58, p < 0.001, n = 110). Human MT (hMT)-inducers, namely Zn, Cu, As, Pb, and Ni; Σ hMT-inducers; 14 more non-inducer metals; and Σ MT-binding metals remained higher (p < 0.05) in EC as compared to NEC. Declining eGFR or CKD progression increased the burden of Be, Mg, Al, V, Co, Ni, Rb, Cs, Ba, Mn, Zn, Sr, Σ hMT-inducers, and Σ MT-binding metals in plasma, suggesting an MT role in the disease. MT1A/2A mRNA followed UACR (PCA, Dendrogram: similarity, 57.7%). The study provides evidence that proteinuric chronic renal failure may increase plasma metal levels where blood MT2A could be a marker