Effects of pond age and a commercial substrate (the water cleanser™) on natural productivity, bacterial abundance, nutrient concentrations, and growth and survival of MARRON (CHERAX CAINII Austin, 2002) in semi-intensive pond culture

Effects of Chitosan–Gentamicin Conjugate Supplement on Non-Specific Immunity, Aquaculture Water, Intestinal Histology and Microbiota of Pacific White Shrimp (Litopenaeus vannamei)

“…The salinity, total alkalinity, NH 3 , and NO 2 − in all the groups were increased, while the NO 3 − content in all groups was decreased. The overall change trends of NH 3 and NO 2 − were similar to those in studies by other experts [ 28 , 29 ]. It is likely that the excessive input of feeds and massive deposition of fecal matter during the feeding period—causing organic matter accumulation, decomposition, and oxygen consumption, resulting in the bottom of tank entering a hypoxic state, a large number of anaerobic bacteria multiplying, and the incomplete decomposition of organic matter—produced a large number of toxic and harmful physical–chemical factors such as ammonia nitrogen and nitrous nitrogen [ 30 ].…”

Effects of seasonal variations and pond age on trace elements and their correlations with plankton productivity in commercial freshwater crayfish ( cherax cainii austin, 2002) earthen ponds

“…Where zooplankton abundance and zooplankton dry weight was significantly higher in old pond during autumn and spring respectively. These results were similar to the findings of Cole et al () where author found the phytoplankton abundance, species diversity and zooplankton abundance were higher in old ponds. In contrast to our result, Abu Hena () reported that the new culture ponds had greater phytoplankton growth than old ponds, attributed to the higher Ca concentration in old ponds, leading to a higher rate of Ca‐phosphate precipitation, in turn resulting into less availability of phosphate in the water to support plankton growth (Abu Hena et al, ).…”

“…But the concentration was not toxic to pond biota as Al is more soluble and potentially toxic to freshwater biota if the pH decreases below 6.0 (Gensemer & Playle, ), and the pH of marron pond water was higher than 7.8 throughout the year. All the physical and chemical water parameters showed seasonal variations (Table ) and were within the optimum range for marron (Cole et al, ).…”

“…throughout the year. All the physical and chemical water parameters showed seasonal variations (Table 6) and were within the optimum range for marron (Cole et al, 2019).…”

“…The next day, the crucible was removed from the oven and placed immediately into the desiccator for half an hour, and then, the filter paper reweighed until a constant weight (W 2 ) was achieved. The plankton abundance was calculated by using the equations from Cole, Tulsankar, Saunders, and Fotedar (2019). The plankton weights were calculated by the following equations;…”