Figure 1.
Physico-chemical characteristics of 0.01% and 0.02% trypsin encapsulated in 0.4% chitosan nanoparticles (TrypCsNPs).
Means bearing different superscript letters differ significantly (*P<0.05 by student t test).Values represent means ± standard error of triplicate observations.
Figure 2.
A] 0.4% chitosan nanoparticles B] 0.01% trypsin encapsulated in 0.4% chitosan nanoparticles, C] 0.02% trypsin encapsulated in 0.4% chitosan nanoparticles and three-dimensional images D] 0.01% trypsin encapsulated in 0.4% chitosan nanoparticles, E] 0.02% trypsin encapsulated in 0.4% chitosan nanoparticles.
Figure 3.
Productive performance and hepatosomatic- and viscero-somatic index of fish on diets containing 0.4% chitosan nanoparticles (CsNPs), 0.02% bare trypsin (bTryp), and 0.01% or 0.02% trypsin encapsulated in 0.4% chitosan nanoparticles (TrypCsNPs).
Means bearing different superscript letters differ significantly (P<0.05). Values represent means ± standard error of triplicate observations.
Figure 4.
Digestibility of diets and intestinal protease activity in fish fed these diets containing 0.4% chitosan nanoparticles (CsNPs), 0.02% bare trypsin (bTryp), and 0.01% or 0.02% trypsin encapsulated in 0.4% chitosan nanoparticles (TrypCsNPs).
Means bearing different superscript letters differ significantly (P<0.05). Values represent means ± standard error of triplicate observations.
Figure 5.
Activities of aminotransferases and dehydrogenases in fish fed diets containing 0.4% chitosan nanoparticles (CsNPs), 0.02% bare trypsin (bTryp), and 0.01% or 0.02% trypsin encapsulated in 0.4% chitosan nanoparticles (TrypCsNPs).
Abbreviations: Aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and malate dehydrogenase (MDH). Means bearing different superscript letters differ significantly (P<0.05). Values represent means ± standard error of six observations.
Figure 6.
Plasma components and serum protein profile in fish fed diets containing 0.4% chitosan nanoparticles (CsNPs), 0.02% bare trypsin (bTryp), and 0.01% or 0.02% trypsin encapsulated in 0.4% chitosan nanoparticles (TrypCsNPs).
Means bearing different superscript letters differ significantly (P<0.05). Values represent means ± standard error of six observations.
Figure 7.
Intestine histology of fish fed control, 0.4% chitosan nanoparticles, 0.02% bare trypsin and and 0.01% or 0.02% nanoencapsulated trypsin containing diets (H&E, 40X).
In control group (A), intestinal mucosa is lined by regularly-packed villi with continuous basement membrane. In 0.4% chitosan nanoparticles fed fish (B), mildly swollen apical surface of villi (1) are noticed. In 0.02% bare trypsin (C-1 and C2), broadened villi, marked foamy cells with lipid vacuoles (2), atrophied submucosal layer and muscularis (3) were evident. In 0.01% trypsin encapsulated in 0.4% chitosan nanoparticles (D), longer villi (4) with healthy apical surface (5) and improved morphological features besides continuous basement membrane are evident. Crypt depth was less in treated groups (6). Distinct mucin producing goblet cells (7) distributed along the villi in nanoencapsulated trypsin groups indicates better gastro-intestinal health. Villi in 0.02% trypsin encapsulated in 0.4% chitosan nanoparticles (E) resembled those in control group (A). Effectiveness and safety of dietary nanoencapsulated trypsin at half the dose rate (0.01%) (D) of bare trypsin (0.02%) (C-1 and C-2) is evident from healthier villi with more height and absorptive surface.