Digestive Enzyme Activities Research Articles

Effects of dietary multienzymes on the growth performance, digestive enzyme activity, nutrient digestibility, excreta noxious gas emission and nutrient transporter gene expression in white feather broilers.

Adding multienzymes to poultry feed rations is recognized as a nutritional strategy aimed at improving poultry performance and health status. Nonetheless, some literatures present an ongoing debate about the extent of multienzymes beneficial impact on poultry growth performance. This study aimed to explore the impacts of dietary multienzyme supplementation on broilers, focusing specifically on growth performance, carcass characteristics, apparent nutrient digestibility, excreta noxious gas emission, and intestinal nutrient transporter gene expression. A total of 3200 broilers were randomly assigned to five groups (8 replicates per treatment group) and treated with the following: normal control (CON), CON + 100g/t multienzyme (ME100), CON + 150g/t multienzyme (ME150), CON + 200g/t multienzyme (ME200), and CON + 250g/t multienzyme (ME250). Supplementing with multienzymes significantly influenced the feed conversion rate (linear, P = 0.007; quadratic, P = 0.024) and the European broiler index (linear, P = 0.004; quadratic, P = 0.016) in broilers. Dietary multienzymes significantly influenced apparent metabolizable energy (quadratic, P = 0.015) and neutral detergent fiber (quadratic, P < 0.001). Moreover, multienzyme supplementation in the diet also decreased the emission of ammonia (linear, P = 0.001; quadratic, P = 0.006) and hydrogen sulfide (quadratic, P = 0.006) in the excreta. In addition, dietary multi-enzyme notably elevated (P < 0.05) the mRNA expression of nutrient transporter genes, including peptide transporter 1 (PePT1), Na-dependent neutral amino acid transporter (B0AT), glucose transporter 2 (GLUT2), and fatty acid binding protein1 (FABP1). These findings suggest that dietary supplementation with multienzymes can improve the efficiency of feed utilization, and the digestion and absorption of nutrients and reduce excreta gas emission. Furthermore, this study provides a theoretical basis for advancing the use of multienzymes in broiler production.

Comparison of the effects of hesperidin over 30 and 60-day intervals on rainbow trout: a potential biostimulant to promote growth, immunological and antioxidant responses, and disease resistance

Abstract The current research evaluated the effects of dietary hesperidin (HSP) on growth parameters, digestive enzyme activities, innate immune markers, and antioxidant responses in rainbow trout, Oncorhynchus mykiss after the 30- and 60-day feeding trial. Then, specimens were subjected to Yersinia ruckeri infection for 14 days. For this, six hundred rainbow trout juveniles (initial weight; 25.49±0.40 g) were fed with different levels of HSP including 0 (HSP0; control), 50 (HSP50), 100 (HSP100), 150 (HSP150), and 200 (HSP200) mg/kg feed. After 60 days, dietary HSP100 supplementation significantly improved growth and feed efficiency indices. The optimal dose of HSP based on the regression test for WG and FCR detected 122 and 131mg/kg, respectively. At the end of the 30th day, dietary HSP150 supplementation markedly boosted serum lysozyme (LYZ), myeloperoxidase (MPO), complement component C3, and immunoglobulin (Ig) levels, as decreased malondialdehyde (MDA) content. In the same period, dietary administration of HSP at the different concentrations markedly increased complement component C4 (HSP150 and HSP200), superoxide dismutase (SOD), skin mucus alkaline phosphatase (ALP) (HSP100- HSP200), skin mucus LYZ and catalase (CAT) (HSP100 and HSP 150), and skin mucus Ig level (HSP50- HSP200). After 60 days, all dietary HSP supplementation significantly improved lipase, serum C3, glutathione peroxidase (GPX), and skin mucus ALP, LYZ, and Ig levels, but decreased MDA, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) values. After 60 days, dietary administration of HSP150 induced a significant discrepancy in the activity of serum LYZ, MPO, respiratory burst (RB), and lactate dehydrogenase (LDH) compared to the control group. In the same period, dietary HSP supplementation at different levels induced a remarkable increase in digestive protease activity (HSP100), serum ACH50 and CAT activities (HSP100 and HSP150), skin mucus peroxidase and serum SOD levels (HSP100-HSP200), and serum C4 value (HSP50, HSP150, and HSP200), but markedly decreased ALP activity (HSP150 and HSP200). In addition, dietary HSP supplementation, especially HSP150, markedly boosted disease resistance against Y. ruckeri infection. The current data demonstrated that the oral administration of 100 - 150 mg/kg HSP has a high potential to promote growth performance, disease resistance, and faster induction of immune and antioxidant responses.

Effects of Bacillus cereusYB1 on growth, intestinal digestive enzyme activity, liver antioxidant enzyme activity, and intestinal structure of black rockfish, Sebastes schlegelii

AbstractWe aimed to investigate the effects of Bacillus cereus YB1 on the growth, intestinal digestive enzyme activity, liver antioxidant enzyme activity, and intestinal tissue structure of juvenile black rockfish (Sebastes schlegelii). A 50‐day feeding experiment was conducted. Feeding was conducted in four diet groups: control group with no YB1 supplement in diet and three treatment groups E‐L, E‐M, and E‐H containing 105, 106, and 107 CFU/g YB1, respectively. The results revealed that the weight gain and specific growth rate of juvenile fish significantly increased, while the feed coefficient was reduced in all three diet treatment groups. This indicated that the growth of black rockfish was significantly and positively affected by YB1 feeding. Enzyme activity in the intestinal tract was not significantly affected by YB1. However, the activity of protease, amylase, and lipase increased because of YB1 treatment, except for the proteases in the E‐M diet group. Meanwhile, no significant differences were recorded in the activities of the antioxidant enzymes in liver, but the level of catalase, superoxide dismutase, and malondialdehyde activities in treatments shows a better performance compared with the control in overall perspective. Furthermore, the structural features of the intestine (i.e., number of intestinal villi, length of gut villi, and thickness of muscularis) was significantly elevated with the inclusion of B. cereus YB1 in the diet. These results reveal that dietary supplementation of B. cereus YB1 is beneficial to the boosting of enzymatic activities and structure of intestinal tissue as well as the antioxidative ability of liver tissue. Such findings suggest that fish growth would be improved under YB1 feeding conditions.

Changes in Digestive Enzyme Activities during Larval Development of Spotted Seatrout (Cynoscion nebulosus)

The spotted seatrout (Cynoscion nebulosus)—an important commercial species—has a high potential for aquaculture in the Gulf of Mexico. To optimize its feeding during larval rearing, this study aims to evaluate the primary gastric (pepsin), intestinal (leucine aminopeptidase and alkaline phosphatase), and pancreatic (alkaline protease, trypsin, chymotrypsin, amylase, and lipase) enzyme activities from hatching to day 30. A multivariate analysis identified three digestive enzyme development stages during the spotted seatrout larval transformation. The first stage occurred between 1 (mean ± standard error (SE) = 1.73 ± 0.14 millimeter (mm) standard length (SL)) and 3 (2.14 ± 0.07 mm SL) days after hatching (DAH); a period of digestive stability showed the highest activity in amylase and bile salt-dependent lipase. The second stage (from 4 (2.53 ± 0.09 mm SL) to 20 (10.92 ± 0.51 mm SL) DAH) was a period of digestive transition, during which leucine aminopeptidase, chymotrypsin, and alkaline proteases were identified as the predominant enzymes from 4 to 5 DAH. In the third stage—a period of digestive stability—pepsin was the major enzyme that occurred between 25 (16.51 ± 0.81 mm SL) and 30 (25.91 ± 0.82 mm SL) DAH. These results indicate that the spotted seatrout larvae have a digestive system adapted to lipids and carbohydrates at the onset of feeding, with an immediate transition to protein digestion when exogenous feeding begins. Additionally, the digestive system of the spotted seatrout may be considered mature at 25 DAH. Further research is needed to elucidate the mechanisms of digestive tract development in the spotted seatrout larvae.

Preparation of valine-curcumin conjugate and its in vitro antibacterial and antitumor activity and in vivo biological effects on American eels (Anguilla rostrata)

Curcumin (Cur) exhibits diverse natural pharmacological activities, despite its limited water solubility (hydrophobicity) and low bioavailability. In this investigation, a valine-curcumin conjugate (Val-Cur) was synthesized through amino acid side chain modification, and its solubility increased to 1.78 mg/mL. In vitro experimental findings demonstrated that the antibacterial activity of Val-Cur against Escherichia coli, Staphylococcus aureus, Aeromonas hydrophila, and Vibrio parahaemolyticus was significantly superior to that of Cur. The inhibition rate of Val-Cur against HepG2 (human hepatocellular carcinoma) cells was higher than that of Cur at low concentrations (below 25 μmol/L), although the IC50 value of Val-Cur did not differ significantly from that of Cur. In vivo biological effects of Val-Cur were assessed by adding it into the feed (150 mg/kg) of American eels (Anguilla rostrata). Val-Cur significantly improved the growth performance (↑weight gain rate, ↑specific growth rate, and ↓feed conversion rate) and activities of intestinal digestive enzymes (amylase and lipase) and antioxidant enzymes (superoxide dismutase) in American eels. Additionally, Val-Cur significantly improved serum biochemical indices (↑high-density lipoprotein cholesterol, ↓low-density lipoprotein cholesterol, ↓aspartate and alanine aminotransferases). Furthermore, Val-Cur increased intestinal microbial diversity, reduced the abundance of potentially pathogenic bacteria (Spiroplasma, Clostridium, and Pseudomonas), and elevated the abundance of beneficial digestion-promoting bacteria (Romboutsia, Phyllobacterium, Romboutsia sedimentorum, and Clostridium butyricum) conducive to glucose metabolism (P < 0.05). To the best of our knowledge, this study is the first to explore water-soluble curcumin in aquaculture, and the findings will lay the groundwork for the potential application of water-soluble curcumin in the field of aquaculture.

Effect of temporal thermal stress on Penaeus vannamei: Growth performance and physiological plasticity.

The present study evaluated the effect of temporal periods of hypothermia and hyperthermia, followed by an optimal temperature recovery phase on the growth, survival, and physiological response of Penaeus vannamei. Post-larvae were exposed to stress periods for 7 and 14 days at 22 °C and 32 °C each, followed by a recovery phase at 28 °C to complete seven experimental weeks, and were compared with a control group maintained at 28 °C. Weight gain, specific growth rate, feed intake, feed conversion ratio, and survival were weekly determined. Muscle, hepatopancreas, and hemolymph were sampled on the 14th day of the recovery phase for biochemical composition, and antioxidant and digestive enzyme activities determination. The shrimp presented a higher growth rate during short-term hyperthermia in contrast to shrimp under hypothermia that presented compensatory growth after thermal stress when the temperature was restored at 28 °C. Hyperthermia increased 12–13% the feed intake while this was diminished 21–29% by the hypothermia periods. Shrimp undergo metabolic adjustments following thermal stress, with short hypothermia increasing the lipase activity and lipid storage in the hepatopancreas, while short hyperthermia also enhances chymotrypsin activity and leads to higher protein and lipid accumulation. Conversely, prolonged hyperthermia induces greater energy consumption, depleting lipid and glycogen stores, while hypothermia causes scarce mobilization of energy reserves during recovery phase. Antioxidant enzyme activities were not affected by short-thermal stress (7d), while prolonged thermal stress (14d) significantly affected SOD, CAT, and GPx activities. The present study provides important insights into the physiological plasticity of P. vannamei during recovery from thermal stress.

Recuperative Effects of Cinnamon (Cinnamomum zeylanicum) in Catla catla After Sub-Lethal Exposure to Lead.

This research was conducted to validate the beneficial effects of incorporating dietary cinnamon (Cinnamomum zeylanicum) powder (CzP) in alleviating lead (Pb) poisoning in fish. Healthy Catla catla individuals (16.36 ± 0.19g/fish) were distributed across 18 tanks in triplicate groups. The experimental groups were as follows: Control group: fish without supplementation or exposure to Pb; positive control group: fish without supplementation but exposed to 1mg/L Pb; 5g/kg CzP along with 1mg/L Pb exposure; 10g/kg CzP along with 1mg/L Pb exposure; 15g/kg CzP along with 1mg/L Pb exposure; and 20g/kg CzP along with 1mg/L Pb exposure. The trial continued for a period of 60days. Waterborne Pb had a deleterious effect on fish growth performance, body composition, blood profile, and digestive enzyme activity, along with elevated Pb accumulation in various tissues. Conversely, consumption of cinnamon effectively mitigated the toxic potential of Pb and enhanced fish longevity. Notably, 10g/kg CzP boosted growth, improved carcass quality, reversed blood indices, restored enzyme function in the gut, and mitigated Pb accumulation in tissues. In summary, the findings revealed that incorporating 10g/kg of CzP as a dietary supplement in C. catla aquaculture could effectively counteract heavy metal toxicity.

Influence of Herba Houttuyniae added to fodder on the morphological structure of the intestinal tract, the digestive enzymes, the intestinal flora, and immune function of koi carp (Cyprinus carpio) infected with Aeromonas veronii.

This study investigated whether adding Herba Houttuyniae to feed can improve intestinal function and prevent diseases for koi carp (Cyprinus carpio) infected with Aeromonas veronii. There was a total of 168 koi carp with an average body length of (9.43 ± 0.99) cm and an average body weight of (26.00 ± 11.40) g. The K group was the control group fed with basal feed, while the C group was fed with feed with a H. houttuyniae content of six per thousand. After 14days of feeding, the fish were fasted for a day and then intraperitoneally injected with A. veronii for artificial infection, injection dose is 0.2mL, and the concentration is 1 × 107CFU/mL. Samples were collected from the two groups on days 0, 1, 2, and 4. The fold height, intestinal villus width, and muscle layer thickness in the gut of the koi carp were measured. In addition, on day 4, the activities of trypsin, α-amylase, and lipase in the gut were determined, and the intestinal flora of the carp in both groups was tested. The results showed that on the second and fourth days of sampling, the fold height and muscle layer thickness in the C group were significantly higher than those in the K group (P < 0.05). The villus width in the C group was slightly higher than that in the K group, but the difference was not significant (P > 0.05). Microscopic observation revealed that the intestinal structure of the carp in the C4 (day 4 in C group) group was more intact than that in the K4 (day 4 in K group) group. Moreover, the activities of trypsin, α-amylase, and lipase in the foregut and midgut in the C4 group were higher than those in the K4 group (P < 0.05). The activities of trypsin and α-amylase in the hindgut in the C4 group were higher than those in the K4 group (P < 0.05). Furthermore, beneficial bacteria, especially those in the genus Cetobacterium, were more abundant in the intestinal tract of the carp in the C4 group compared to the K group. In addition, comparisons and tests of IL-4 and IL-10 in the intestines of the fish in both groups demonstrated that the H. houttuyniae added to feed enhanced the immune function of the fish intestines after bacterial attack. In conclusion, for koi carp infected with A.veronii, adding H. houttuyniae to their feed not only improves the activity of digestive enzymes and the morphological structure of the intestine but also optimizes the beneficial intestinal microbiota, thereby protecting the intestinal tract.

Exploring the relationship between dietary rapeseed meal, condensed tannin and growth, nutrive metabolism in largemouth bass (Micropterus salmoides)

This study evaluated the effects of rapeseed meal (RM) and condensed tannin (CT) on the growth and nutritional metabolism of largemouth bass (Micropterus salmoides), and speculated whether there was interaction between anti-nutritional factors in RM. Eight diets were formulated for 55-day feeding trial, six of which were practical diet groups, including control group (CG), five RM inclusive groups with graded RM levels of 5% (RM5), 10% (RM10), 15% (RM15), 20% (RM20) and 25% (RM25) partially replacing fishmeal, and the other two were semi-purified diets with 0.062% CT (CT5) ≈ the CT content in the RM5 and 0.31% CT (CT25) ≈ the CT content in the RM25. The results of the experiments on replacing fishmeal with RM demonstrated that with the increase of RM substitution level, the weight gain rate (WGR), survival rate (SR) and specific growth rate (SGR) of largemouth bass showed a downward trend. High levels of RM led to the inhibition of digestive enzyme activity in largemouth bass, as well as the manifestation of abnormal markers related to protein, fat, and carbohydrate metabolism in both plasma and liver. RM reduced muscle protein and fat content, although the effect was not statistically significant at 5% RM level. The results of CT concentration experiments showed that the addition of 0.31% CT significantly reduced WGR, SGR, SR, protein efficiency ratio (PER) and gastrointestinal digestive enzyme activity, and significantly increased the feed coefficient ratio (FCR), plasma ammonia (PA), plasma glucose (PG), and hepatic glycogen (HG) and liver triglyceride (TG). The addition of 0.062% CT significantly reduced PG and HG. Supplementation of CT significantly reduced muscle fat. Among the groups of CT supplementation and RM, CT5 exhibited superior WGR, PER and FCR compared to RM5, along with enhanced intestinal trypsin, amylase activity, liver glutamic pyruvic transaminase (GPT) activity and decreased content of HG and liver TG; CT25 exhibited decreased activities of gastric lipase (LPS), enteric trypsin and pepsin, and increased content of total cholesterol (T-CHO) and glucose in plasma in compariosn to RM25, accompanied with no significant change in growth performance. Therefore, largemouth bass exhibited tolerance to a 5% inclusion of RM in the feed without compromising their growth, digestion and metabolic functions. The incorporation of 5% RM, equivalent to a supplemental 0.062% CT, had regulatory effects on the digestion and metabolism of largemouth bass while improving feed utilization. There was an interaction among anti-nutritional factors in RM, with synergistic effect being evident at low RM levels, whereas antagonism more promient at high levels of RM.

Effectiveness of lycopene dietary enrichment for growth performance, digestive enzymes, blood health, immunity, and antioxidant status of common carp (Cyprinus carpio) against chronic glyphosate toxicity

For food safety challenges, sustainable aquaculture emerges as a significant source in recent years; however, despite its potential, the industry still facing challenges, notably the exposure of cultured animals to pesticidal pollution. This pollution originating from agricultural practices that can enter aquaculture system directly: to integrated-agriculture aquaculture practices, or indirectly via soil leakage. Current research based on glyphosate (GLY) toxicity and its amelioration by lycopene (LYC). Four fish groups used for six-weeks experiment in which four groups were used. Control group (CL) was fed with basal commercial diet only without any LYC and GLY exposure; 2) LYC group: exposed to LYC supplemented diet (15 mg/kg per fish diet); 3) GLY group: exposed to glyphosate only (1/5th of 96 h LC50: 0.0892 mg/L) with basal commercial diet, and; 4) GLY + LYC group: exposed to both lycopene supplemented diet (15 mg/kg per fish diet) and glyphosate (1/5th of 96 h LC50: 0.0892 mg/L). GLY observed to decrease growth parameters and feed utilization whereas, lycopene ameliorated growth rate (WG, SGR, HSI, CF) and feeding utilization (FCR) as compared to the control group. Also, GLY induced toxicity within hematobiochemical parameters with alleviation by LYC supplementation. GLY induced cytotoxicity was observed within RBCs as lobbing, notching, vacuolation, blebbing, micronuclei, and condensation. Increase in reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) were observed by GLY exposure. Also, there is observed reduction in antioxidant enzyme activities (CAT, SOD, POD, TPC and GSH) upon GLY exposure. Lipid peroxidation (malondialdehyde: MDA), 8-OHdG (8-hydroxy-2′-deoxyguanosine) and DIY (dityrosine) observed to increase by GLY toxicity. There was improvement in immune responses; increased AChE (acetylcholinesterase) activity, lysozyme content, ACP (acid phosphatase), NBT (nitro blue tetrazolium), NO (nitric oxide) and IgM levels (immunoglobulin M) and digestive enzyme activities (protease, lipase and amylase) observed by LYC supplemented diet. Taken together, LYC supplementation observed to alleviate GLY induced oxidative stress and cytotoxicity with improved immunity, digestive actions and blood health within C. carpio. Therefore, dietary supplementation with lycopene can protect common carp from the harmful effects by glyphosate within agri-integrated aquaculture practices, so suggesting it as potential feed additive.

Growth performance, health status and flesh quality of striped catfish (Pangasianodon hypophthalmus) reared in variable stocking densities in biofloc system

Optimization of ideal stocking density in intensive aquaculture system is a challenging appraisal. Higher stocking density is inducing chronic stress, impacting negatively on physiology and increasing disease associated risks in fish. Hence, the study was designed to evaluate the water quality, growth performance, health status and flesh quality of striped catfish (Pangasianodon hypophthalmus). The fish (2.61–2.64 ± 0.01 g initial body weight) were reared in randomly designed variable stocking densities (SDs) including five treatments (30, 40, 50, 60 and 70 fish m−3) in triplicates at C:N ratio 15:1 in jaggery supplemented biofloc system for 120 days in 1000 –L experimental fiber-reinforced plastic tanks. SD30 acted as control treatment having low stocking density. During the culture, pH, alkalinity and dissolved oxygen level decreased and BOD increased with increased stocking density. TDS and TSS level increased upto SD50 treatment and further decreased in higher stocking density treatments. Higher population of heterotrophic, ammonifying and nitrifying bacteria significantly (p < 0.05) reduced TAN, NH3-N, NO2-N, and elevated NO3-Nas well as rate and potential of ammonification and nitrification in SD50 treatment than other treatments. Bacillariophyceae and protozoa were most dominant group in the biofloc microbiome in all the treatments. Highly elevated biofloc volume, floc microbiome, good floc characteristics and floc quality might have enhanced fish survival rate, body weight gain, SGR through improving FCR in SD50 than other SDs. Moreover, higher population of gut microbiota (TPC and probiotic) and elevated digestive enzymes activity in fish reared in SD50 treatment significantly (p < 0.05) enhanced PER, ANPU, and somatic indices (GSI and HSI) as well as enhanced colour (lightness, yellowness/blueness and whiteness), flesh quality and hardness. Fish reared in SD50 treatment showed significantly (p < 0.05) higher haematological (TEC, TLC and Hb), immunological (TSP, albumin, RBA and lysozyme), antioxidant responses (higher SOD and CAT) and lower metabolic stress enzymes responses (ALT, AST and glucose). Moreover, fish reared in SD50 treatment showed improved villi surface area and height in intestine and slightly vacuolated hepatocytes in liver. Overall, significantly (p < 0.05) better water quality, fish performance, health status and flesh quality were observed in SD50. Collectively, the findings suggest that farmers can be benefitted by fetching higher production through suitable stocking density (50fish m−3) of P. hypophthalmus in biofloc with improved water quality, growth performance, health status and flesh quality.

Pediococcus pentosaceus ZZ61 enhances growth performance and pathogenic resistance of silkworm Bombyx mori by regulating gut microbiota and metabolites

Probiotics have attracted considerable attention in animal husbandry due to their positive effect on animal growth and health. This study aimed to screen candidate probiotic strain promoting the growth and health of silkworm and reveal the potential mechanisms. A novel probiotic Pediococcus pentosaceus strain (ZZ61) substantially promoted body weight gain, feed efficiency, and silk yield. These effects were likely mediated by changes in the intestinal digestive enzyme activity and nutrient provisioning (e.g., B vitamins) of the host, improving nutrient digestion and assimilation. Additionally, P. pentosaceus produced antimicrobial compounds and increased the antioxidant capacity to protect the host against pathogenic infection. Furthermore, P. pentosaceus affected the gut microbiome and altered the levels of gut metabolites (e.g., glycine and glycerophospholipids), which in turn promotes host nutrition and health. This study contributes to an improved understanding of the interactions between probiotic and host and promotes probiotic utilization in sericulture.

Changes in growth, morphology, and levels of digestive enzymes and growth-related hormones in early ontogeny of black scraper, Thamnaconus modestus

IntroductionThe black scraper, Thamnaconus modestus, is a highly valued marine fish species, but its output has gradually decreased in recent years, which may be due to its low survival rate during early ontogenesis.MethodsTherefore, in this study, we assessed the changes in growth, morphology, digestive enzymes, and hormone levels in T. modestus from 0–60 days post-hatching (dph) and revealed growth turning points by morphological measurement and determination of digestive enzyme activities and hormone levels. We found that ontogenesis could be divided into the larval (0–20 dph) and juvenile (20–60 dph) stages. Acid and alkaline protease activity significantly increased and decreased, respectively, from 12–25 dph, likely due to the development of stomach and gastric glands. Acid phosphatase levels significantly increased at 0 and 4 dph, which may be related to the regulation of metabolism and immune protection. A sharp increase in alkaline phosphatase levels at 20 and 25 dph was observed and was likely due to the development of the brush border membrane of enterocytes. The amylase level was significantly higher at 25, 30, and 35 dph, possibly due to better digestion and absorption during the transition from consuming Artemia to compound feed. In newly hatched larvae, the level of thyroid hormones triiodothyronine (T3) and thyroxine (T4) gradually increased and peaked at 35 dph, highlighting the importance of these hormones during the development of T. modestus. Growth hormone (GH) levels first increased from 0–8 dph, with a plateau at 8–20 dph, and then increased at 25–30–35 dph. For insulin-like growth factor 1 (IGF-1), a significant increase with a subsequent plateau was observed between 8 and 20 dph, followed by a substantial decrease between 30 and 35 dph. These results suggest that the regulating functions of GH and IGF-1 are synchronised. Digestive enzyme activity and hormone levels of abnormal fry at 30 dph were lower than those of normal fish, highlighting the importance of specific hormones, especially T4 and IGF-1, in the development of T. modestus.

The performance and physiological responses of Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae) to different sorghum cultivars

Utilizing pest-resistant cultivars is a highly effective and environmentally-friendly approach for managing crop infestations by pests. In the present study, the differences in the resistance of eight cultivars of Sorghum bicolor (L.) Moench (Kimia, Payam, Pegah, Sepideh, Spidfid, KGS23, KFS2, and KFS18) against Rhyzopertha dominica (F.) (Coleoptera: Bostrichidae), a polyphagous pest of stored products, were evaluated based on demographic parameters, nutritional indices, and digestive enzymatic activities within the pest. The results revealed that the development time of R. dominica was the shortest when reared on Kimia, Spidfid, and KFS2, while the longest was recorded in those fed on Payam and Pegah. The fecundity of R. dominica was the lowest on Pegah. Furthermore, Kimia and Sepideh showed the highest intrinsic rate of increase (r) and finite rate of increase (λ), whereas the lowest values for these parameters were observed on Pegah and KGS23. The highest relative growth rate (RGR) of R. dominica was achieved on Sepideh, whereas the lowest RGR was observed on KGS23. The highest level of digestive proteolytic activity in R. dominica was observed on Sepideh, whereas the lowest level was found on KGS23. The amylolytic activity in R. dominica was the highest on Sepideh, and the lowest on Pegah and KGS23. The findings showed significant negative correlations between fecundity, intrinsic rate of increase, and amylolytic activity of the pest with the total phenolic content of the studied sorghum cultivars. Furthermore, the results obtained from cluster analysis revealed that Sepideh, Kimia, and KFS2 were the susceptible cultivars for population growth of R. dominica, while Payam, Pegah, and KGS23 were the partially resistant hosts for this pest. The pest-resistant sorghum cultivars identified in this study can potentially be utilized in combination with other pest control strategies for sustainable management of R. dominica, which may help reduce the excessive use of chemical insecticides.

Pancreatic Diseases: Genetics and Modeling Using Human Pluripotent Stem Cells.

Pancreas serves endocrine and exocrine functions in the body; thus, their pathology can cause a broad range of irreparable consequences. Endocrine functions include the production of hormones such as insulin and glucagon, while exocrine functions involve the secretion of digestive enzymes. Disruption of these functions can lead to conditions like diabetes mellitus and exocrine pancreatic insufficiency. Also, the symptoms and causality of pancreatic cancer very greatly depends on their origin: pancreatic ductal adenocarcinoma is one of the most fatal cancer; however, most of tumor derived from endocrine part of pancreas are benign. Pancreatitis, an inflammation of the pancreatic tissues, is caused by excessive alcohol consumption, the bile duct obstruction by gallstones, and the premature activation of digestive enzymes in the pancreas. Hereditary pancreatic diseases, such as maturity-onset diabetes of the young and hereditary pancreatitis, can be a candidate for disease modeling using human pluripotent stem cells (hPSCs), due to their strong genetic influence. hPSC-derived pancreatic differentiation has been established for cell replacement therapy for diabetic patients and is robustly used for disease modeling. The disease modeling platform that allows interactions between immune cells and pancreatic cells is necessary to perform in-depth investigation of disease pathogenesis.

Effects of Dietary Supplementation of Bile Acids on Growth, Glucose Metabolism, and Intestinal Health of Spotted Seabass (Lateolabrax maculatus).

An 8-week feeding trial was performed to investigate the effects of dietary bile acids on growth, glucose metabolism, and intestinal health in spotted seabass (Lateolabrax maculatus) reared at high temperatures (33 °C). The fish (20.09 ± 1.12 g) were fed diets supplemented with bile acids: 0 (Con), 400 (BA400), 800 (BA800), and 1200 (BA1200) mg/kg, respectively. The results showed that the growth was promoted in fish at the BA800 treatment compared with the control (p < 0.05). Increased enzyme activities and transcripts of gluconeogenesis in the liver were observed, whereas decreased enzyme activities and transcripts of glycolysis, as well as glycogen content, were shown in the BA800 treatment (p < 0.05). The transcripts of bile acid receptors fxr in the liver were up-regulated in the BA800 treatment (p < 0.05). A bile acid supplementation of 800 mg/kg improved the morphological structure in the intestine. Meanwhile, intestinal antioxidant physiology and activities of lipase and trypsin were enhanced in the BA800 treatment. The transcripts of genes and immunofluorescence intensity related to pro-inflammation cytokines (il-1β, il-8, and tnf-α) were inhibited, while those of genes related to anti-inflammation (il-10 and tgf-β) were induced in the BA800 treatment. Furthermore, transcripts of genes related to the NF-κB pathway in the intestine (nfκb, ikkα, ikkβ, and ikbα1) were down-regulated in the BA800 treatment. This study demonstrates that a dietary bile acid supplementation of 800 mg/kg could promote growth, improve glucose metabolism in the liver, and enhance intestinal health by increasing digestive enzyme activity and antioxidant capacity and inhibiting inflammatory response in L. maculatus.

Influence of vasoactive intestinal polypeptide on growth performance, nutrient digestibility, nitrogen balance, and digestive enzyme activity in lambs.

This study evaluated if vasoactive intestinal polypeptide (VIP) influences growth performance, nutrient digestibility, nitrogen balance, and digestive enzyme activity. Sixteen wether lambs (69.6 ± 1.9kg) were housed in individual pens, adapted to a corn grain-based diet, and randomly assigned to 2 treatment groups. Lambs were injected intraperitoneally every other day for 28 days with saline (0.9% NaCl) containing no VIP (n = 8; control) or containing VIP (n = 8; 1.3 nmol/kg BW). All lambs were transferred to individual metabolic crates for the final seven days of the experiment to measure nitrogen balance and nutrient digestibility. At the end of the treatment period, lambs were slaughtered, and pancreatic tissue, small intestinal tissue, and rumen fluid were collected for protein, digestive enzymes, ruminal pH, and volatile fatty acid (VFA) analyses. Lambs treated with VIP had greater final body weight, average daily gain, and gain:feed (P = 0.01, 0.05, 0.03, respectively). No differences between treatment groups were observed (P ≥ 0.25) for nutrient intake, digestibility, nitrogen retention, ruminal pH, and VFA concentrations. Moreover, VIP treatment did not influence (P ≥ 0.19) plasma glucose, urea N, and insulin concentrations. Treatment with VIP increased (P = 0.03) relative cecum weight (g/kg body weight) and decreased (P = 0.05) relative brain weight. Pancreatic and intestinal digestive enzyme activities, except for duodenal maltase (P = 0.02), were not influenced (P ≥ 0.09) by VIP treatment. These data suggest that the administration of VIP may have potential to improve average daily gain and gain:feed in lambs fed grain-based diets.

Effects on growth performance and immunity of Monopterus albus after high temperature stress.

To investigate the impact of the effect of high temperature stimulation on Monopterus albus larvae after a certain period of time, five experimental groups were established at different temperatures. Then, the M. albus under high temperature stress was fed at 30°C for 70days. After that, the growth index of the M. albus was counted and analyzed. In terms of growth index, high temperature stress had significant effects on FCR, FBW, WGR, and SGR of M. albus (p < 0.05). The SR increased after being stimulated by temperature (p < 0.1). The study revealed that liver cells of M. albus were harmed by elevated temperatures of 36°C and 38°C. In the experimental group, the activities of digestive enzymes changed in the same trend, reaching the highest point in the 32°C group and then decreasing, and the AMS activity in the 38°C group was significantly different from that in the 30°C group (p < 0.05). The activities of antioxidase in liver reached the highest at 34°C, which was significantly different from those at 30°C (p < 0.05). In addition, the expression levels of TLR1, C3, TNF-α, and other genes increased in the experimental group, reaching the highest point at 34°C, and the expression level of the IL-1β gene reached the highest point at 32°C, which was significantly different from that at 30°C (p < 0.05). However, the expression level of the IRAK3 gene decreased in the experimental group and reached its lowest point at 34°C (p < 0.05). The expression level of the HSP90α gene increased with the highest temperature stimulus and reached its highest point at 38°C (p < 0.05). In the α diversity index of intestinal microorganisms in the experimental group, the observed species, Shannon, and Chao1 indexes in the 34°C group were the highest (p < 0.05), and β diversity analysis revealed that the intestinal microbial community in the experimental group was separated after high temperature stimulation. At the phylum level, the three dominant flora are Proteus, Firmicutes, and Bacteroides. Bacteroides and Macrococcus abundance increased at the genus level, but Vibrio and Aeromonas abundance decreased. To sum up, appropriate high-temperature stress can enhance the immunity and adaptability of M. albus. These results show that the high temperature stimulation of 32°C-34°C is beneficial to the industrial culture of M. albus.

Effects of abamectin nanocapsules on bees through host physiology, immune function, and gut microbiome

Pesticide usage is a common practice to increase crop yields. Nevertheless, the existence of pesticide residues in the surrounding environment presents a significant hazard to pollinators, specifically the potential undisclosed dangers related to emerging nanopesticides. This study examines the impact of abamectin nanocapsules (AbaNCs), created through electrostatic self-assembly, as an insecticide on honey bees. It was determined that AbaNCs upregulated detoxification genes, including CYP450, as well as antioxidant and immune genes in honey bees. Furthermore, AbaNCs affected the activity of crucial enzymes such as superoxide dismutase (SOD). Although no apparent damage was observed in bee gut tissue, AbaNCs significantly decreased digestive enzyme activity. Microbiome sequencing revealed that AbaNCs disrupted gut microbiome, resulting in a reduction of beneficial bacteria such as Bifidobacterium and Lactobacillus. Additionally, these changes in the gut microbiome were associated with decreased activity of digestive enzymes, including lipase. This study enhances our understanding of the impact of nanopesticides on pollinating insects. Through the revelation of the consequences arising from the utilization of abamectin nanocapsules, we have identified potential stress factors faced by these pollinators, enabling the implementation of improved protective measures.

Dietary Poly-β-Hydroxybutyrate Improved the Growth, Non-specific Immunity, Digestive Enzyme Activity, Intestinal Morphology, Phagocytic Activity, and Disease Resistance Against Vibrio parahaemolyticus of Pacific White Shrimp, Penaeus vannamei.

This study assessed the effects of dietary supplementation of poly-β-hydroxybutyrate (PHB) on growth performance, feed efficiency, non-specific immunity, digestive enzyme capacity, phagocytic activity, hemocyte count, intestinal morphology, and disease resistance against Vibrio parahaemolyticus of Pacific white shrimp (Penaeus vannamei). Six diets were prepared by supplementing graded levels of PHB at 0.00, 0.25, 0.50, 1.00, 2.00, and 4.00% (Con, P0.25, P0.5, P1.0, P2.0, and P4.0, respectively). Triplicate groups of 90 shrimps (initial body weight 0.25 ± 0.01g) per treatment were randomly assigned and fed an experimental diet for 56days. The growth performance of shrimp was significantly improved by 1% dietary PHB supplementation. PHB-included diets fed shrimp showed significantly improved hepatopancreatic trypsin, chymotrypsin, and pepsin activities. Villus height was significantly increased with dietary PHB supplementation, and villus width was increased at a 1% inclusion level. P0.25, P0.5, and P4.0 groups significantly increased phenoloxidase activity, and the P2.0 group significantly increased anti-protease activity compared to the Con group. The survival of shrimp challenged against V. parahaemolyticus was higher in P0.5, P1.0, and P2.0 groups than in the Con diet. Dietary PHB supplementation improved weight gain, digestive enzyme activity, intestinal morphology, non-specific immunity, and disease resistance against V. parahaemolyticus of shrimp. According to the above observations, the optimal dietary PHB supplementation level for maximum weight gain would be 1% for Pacific white shrimp.