Thumbnail Image

Thesis

Browse

20191
Reset filters
Subject: Zoology × Author: Bhanot, Reetu × End date: 2023 × Type: Thesis × Thesis Type: Ph.D ×
Reset filters

Search Results

Now showing 1 - 1 of 1
  • Thumbnail Image
    ThesisItemOpen Access
    Assessment of Cytotoxicity in Flesh, Gills and Liver of Fish (Labeo rohita) Reared in Untreated and Treated Sewage Water
    (Punjab Agricultural University, Ludhiana, 2019) Bhanot, Reetu; Hundal, S.S.
    The unregulated discharge of municipal sewage water in the water bodies acts as a major threat to the aquatic ecosystem and is also known to induce detrimental effects to the inhabiting fauna. The present study was designed to examine the cytotoxicity in fingerlings of Labeo rohita after exposure to untreated and treated sewage water for different intervals. The acute toxicity test was conducted for 96 hr to determine LC50 of the untreated sewage water (UT) using five concentrations viz. 10%, 25%, 50%, 75% and 100%. The results of acute toxicity test depicted that 75% and 100% concentration of UT induced 100% mortality in fingerlings in less than 48 hr and 24 hr, respectively. After determining 96 hr LC50 value of UT, fingerlings were divided into four groups: control, treated, 1/10th of LC50 UT and 1/20th of LC50 UT. The fingerlings were exposed and dissected at the interval of 15, 30, 45 and 60 days and additional 60 days for recovery. The results of chronic toxicity test revealed significant decrease (p<0.05) in morphometric parameters viz. body weight, body length, weight of liver, gills and flesh of 1/10th LC50 UT and 1/20th LC50 UT groups in comparison to control and treated groups. Significant histopathological alterations were also observed in the gills and flesh of 1/10th and 1/20th LC50 UT group. The biochemical studies depicted a significant decrease (p<0.05) in the level of total proteins in flesh and liver; the total lipids in flesh, however, depicted significant increase (p<0.05) in 1/10th LC50 UT and 1/20th LC50 UT groups. The analysis of fatty acid composition of flesh of fingerlings revealed significant decrease (p<0.05) in per cent of polyunsaturated fatty acids (PUFA’s) and monounsaturated fatty acids (MUFA’s), however, saturated fatty acids (SFA’s) indicated significant increase (p<0.05) in 1/10th LC50 UT and 1/20th LC50 UT groups. The evaluation of antioxidant profile of liver revealed a significant increase (p<0.05) in the levels of LPO and specific activity of catalase, GST and GR, however, the specific activity of SOD and GPx decreased significantly (p<0.05) in both 1/10th LC50 UT and 1/20th LC50 UT groups. High frequency of micronucleated cells (MN) was observed in gill cells of 1/10th LC50 UT and 1/20th LC50 UT group. DNA damage was also observed in gills and flesh of 1/10th and 1/20th LC50 UT groups. A significant recovery (p<0.05) was observed in weight of liver and muscles, histo-architecture of gills and flesh, biochemical parameters viz. proteins in flesh, total lipids in flesh, PUFA’s, SFA’s, MUFA’s, oxidative stress parameters viz. LPO, SOD, catalase, GPx, GR, GST , frequency and number of micronucleated cells (MN) in gills cells of 1/10th LC50 UT and 1/20th LC50 UT groups. Hence, the results of the present study implied that untreated sewage water at the level of 1/10th and 1/20th LC50 has a potential to bring alterations at cellular, organ and genetic level, and after treatment the water is safe for use in fish culture.