Relationship Between Physico-Chemical Parameters and Reproductive Indices of Parachanna obscura (Gunther 1861) in Eleyele Reservoir, Ibadan, Nigeria

Abstract

Propagation in fishes depends on the level of gonad maturation which could be influenced by environmental conditions. However, declining water quality due to environmental degradation has been identified as a hindrance to such ecosystem services in aquatic ecosystems. Therefore, size distribution and stages of gonad development of P. obscura in relation to physic-chemical parameters of Eleyele reservoir were studied. Samples of water and Parachanna obscura were collected monthly from five stratified sampling points and fishers catch, respectively for 24 months. Fish were grouped according to sizes (10-15.9, 16.0-19.9 and ≥ 20 cm), and gonads assessed for maturation. Relationship between reproductive indices and physic-chemical parameters were determined using Principal Component Analysis. The size-groups distributions were 10-15.9 cm (28.6%), 16.0-19.9 cm (38.7%) and ≥ 20 cm (32.7%). All the five maturation stages (I-V) were discerned in the female while only stages II-IV were observed in male samples. All the size groups showed strong associations with pH (β=0.346), ammonia (β=0.303) and temperature (β=0.161). Ovary development was significantly influenced by DO (β=0.827), TDS (β=0.777) and TS (β=0.813), while testes maturation was more influenced by temperature (β=0.626). This information will serve as guides for effective ecosystem management through the control of anthropogenic activities on this reservoir and similar water bodies to enhance resource conservation and/or sustainable management.

Ponds’ Water Quality Analysis and Impact of Heavy Metals on Fishes’ Body

“…Nowadays, different anthropogenic activities including agriculture, industries (Joda et al, 2019;Aris et al, 2020) urban run-off (Adeossun et al, 2015;Montazer et al, 2018) mining activities (Shahbaaet al, 2020;Soulivongsa et al, 2020) and geochemical structure (Naggar et al, 2018) increases the aquatic heavy metals pollution (Shahbaaet al, 2020;Ma et al, 2020). The quality of water affects aquatic life (Olanrewaju et al, 2017;Tulsankar et al, 2020) this is why ponds' management is a key during fish farming (Agyakwah et al, 2020) for its importance for aquatic biodiversity (Hornbach et al, 2020) as poor water quality reduce fishes yield (Makori et al, 2017). The existence of trace and accepted heavy metals level are needed by living body (Shahbaaet al, 2020) including fishes to function and survive (Shafiuddin et al, 2019) but its higher concentration contaminates the fishes (mal-growth and reproduction disorder, mainly the skin, gills, liver, spleen, and kidneys alteration) (Arantes et al, 2015), and even the consumers (human health) indirectly through food chain (Kamaruzzaman et al, 2020;Liu et al, 2020).…”