Evaluation of oxytetracycline hydrochloride (OTC) on non‐specific immunity, enzymatic profiles and tissue level retention in Labeo rohita (Hamilton, 1822) after administration through feed

Abstract

The present study was conducted to assess the effect of oxytetracycline hydrochloride (OTC) in rohu, Labeo rohita, with graded doses viz., 80 (1×), 240 (3×), 400 (5×) and 800 (10×) mg kg −1 fish biomass day −1 respectively through feed. Four hundred and fifty healthy rohu juveniles (20 ± 0.12 g) were fed for 30 days followed by 10 days of withdrawal period. Each 10 days intervals, five fish were randomly sampled for blood, serum and tissue for estimation of growth, non-specific immune parameters, enzymatic activities and retention of OTC in muscle tissue. The results showed that there was no significant difference (p > .05) on growth in the treated fish compared with the control. Respiratory burst activity, myeloperoxidase activity, bacterial haemagglutination and haemolysis activities were enhanced significantly (p < .05) on 10 th and 20 th day in the fish fed with 80 and 240 mg kg −1 biomass day −1 respectively during the feeding trial compared with the control. Lactate dehydrogenase and alkaline phosphatase activity increased significantly (p < .05) in the fish fed with 400 and 800 mg kg −1 biomass day −1 respectively compared with the control. Liquid chromatographymass spectrometry/mass spectrometry study of muscle tissue reveals that OTC was retained in muscle tissue in a dose dependent manner and significantly (p < .05) lowest level (0.44 ± 0.03 ppb) was observed on 40 th day in the treated fish fed with 80 mg kg −1 biomass day −1 . Hence, 80 mg kg −1 fish biomass day −1 of OTC may be adhered in L. rohita for treating the fish through feed with 10 days of withdrawal period.

Effect of Graded Levels of Dietary Emamectin Benzoate on Immunity, Enzyme Activity, and Withdrawal Period in Labeo rohita Juveniles (Hamilton, 1822)

“…Furthermore, it is possible to assume that because of detoxification of EB continuously for 21 days, AST/ALP increased in blood/serum [24] which have been observed in our findings also. Similar phenomena regarding enzyme activities in serum have been reported in another antibiotic related study where OTC was fed with basal feed and found to be caused hepatic damages in L. rohita [35] and OTC-treated rat [41] to some extent which are in line with our present findings. So, it might be inferring that higher dose of EB has detrimental effect in the internal organs (changes in serum hepatic enzymes); hence, further studies with histopathological intervention should be carried out to make the constructive conclusion on it.…”

“…Serum biochemical parameters mainly hepatic enzymes have been recognized as a valuable tool for monitoring the metabolic and physiological health status of fish after treatment with any chemicals or drugs or supplements [35,40]. Likewise, in the present investigation, selected hepatic enzymes which deal with stress as well as biomarker for tissue damage have been evaluated in weekly intervals during the administration and also during the withdrawal of the same drug.…”

“…Experimental fish fed with minimum dose (1x and 2.5x dose) of EB significantly improved respiratory burst activity, myeloperoxidase activity, bacterial haemagglutination, and haemolysis and lasted for 14 days and become normal after withdrawal of the same on the 35 th day. Host 7 Aquaculture Nutrition immune responses against any supplements might play according to the existing or surrounding water temperature, supplement dose, and route of administration of such component to the host which ultimately effects drug absorption, and for that reason findings of these studies are always species specific [34,35] Furthermore, few studies have indicated that dietary levamisole (drug) could significantly enhance RBT activities in various fish species [36][37][38]. Likewise, in the present investigation, time course pattern showed that EB also induced elevation of RBT activity in the blood of fish peaked on 14 days of drug postexposure.…”

Growth performance and immune responses of pengba ( Osteobrama belangeri ) during high‐density fingerling rearing in biofloc system

“…Continuous build‐up of the nutrients such as TAN, nitrite, nitrate and phosphorus is also due to the accumulation of the metabolic waste in the tanks. All these parameters recorded in the treatments were within the tolerable limit for carps (Das, Swain, et al, 2021; Jena et al, 2011; Pawar et al, 2009). But it was interesting to note that the nutrient concentration in the two lower densities (T‐1 and T‐2) were much similar to those in the highest density (T‐4), whereas T‐3 showed lower and more stabilized TAN, nitrite and nitrate concentration.…”

Usage pattern of chemicals, biologicals and veterinary medicinal products in Indian aquaculture

“…74,93 Dose and regimen optimization, clinical outcomes, pharmacokinetics and pharmacodynamics, withdrawal period and antibiotic degradation have been extensively studied. 94 Safety, tissue distribution, depletion and withdrawal period of OTC have been reported extensively in Oreochromis spp., 95,96 Gambusia holbrooki, 97 Oncorhynchus mykiss, 98 Oreochromis niloticus, [99][100][101] Trachinotus blochii, 102 Pangasianodon hypophthalmus, 103 Labeo rohita, 104 Dicentrarchus labrax, 105 Sparus aurata 105,106 and P. vannamei etc. 107 OTC is known to rapidly degrade in aquaculture environments through photo and thermo-degradation.…”