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An 8-wk feeding trial was conducted to determine the dietary choline requirement for juvenile hybrid tilapia, Oreochromis niloticus x O. aureus. Purified basal diets were formulated using vitamin-free casein (contained 370 mg choline/kg) as the protein source. Graded levels (0, 100, 200, 400, 600, 800, 1,000 and 2,000 mg choline/kg diet) of choline chloride were added to the basal diet, resulting in eight dietary treatments in the experiment. Each diet was fed to three replicate groups of tilapia initially averaging 0.62 +/- 0.01 g/fish in a closed, recirculating rearing system. Feed efficiency, survival and blood triglyceride, cholesterol and phospholipid concentrations were generally high in fish fed choline-supplemented diets compared to fish fed the control diet. Analysis by broken-line regression of weight gain and body choline concentration and by polynomial regression of liver lipid concentration of the fish indicated that the dietary choline concentration for tilapia is about 900 mg/kg. Taking into account the choline concentration of the unsupplemented basal diet, the optimal dietary choline requirement for growing tilapia is about 1,000 mg/kg. [ABSTRACT FROM AUTHOR]

Two growth experiments were conducted to estimate the minimal dietary vitamin A requirement for juvenile grass shrimp, Penaeus monodon. In expt. 1, purified diets containing 0, 1,500, 3,000, 15, 000, 30,000, 45,000 and 60,000 retinol equivalent (RE)/kg (i.e., 0, 5,000, 10,000, 50,000, 100,000, 150,000, 200,000 IU/kg) of supplemental vitamin A (retinyl acetate) were fed to P. monodon (mean initial weight 0.97 +/- 0.01 g) for 8 wk. In expt. 2, diets with 0, 600, 1,200, 1,800, 2,400, 3,000, 3,600, and 4,500 RE/kg (i.e. , 0, 2,000, 4,000, 6,000, 8,000, 10,000, 12,000, 15,000 IU/kg) of supplemental vitamin A were fed to the shrimp (mean weight 0.68 +/- 0.01 g) for 6 wk. The basal unsupplemented diet contained 54 RE vitamin A/kg, and supplemental levels were confirmed by analysis. Each diet was fed to three replicate groups of shrimp. In expt. 1, shrimp fed diets supplemented with 300 RE vitamin A/kg had significantly greater weight gain (P < 0.05) than those fed the unsupplemented control diet and diets supplemented with >===" BORDER="0">30,000 RE vitamin A/kg. Survival rate was higher in shrimp fed diets supplemented with 1,500-30,000 RE vitamin A/kg than shrimp fed the control diet. Highest blood triglyceride concentration and body lipid concentration were in shrimp fed diets supplemented with 45,000 and 60,000 RE vitamin A/kg, respectively. Eye vitamin A concentration and hepatopancreatic total lipid concentration in shrimp generally increased as dietary vitamin A supplementation increased. In expt. 2, feed efficiency was highest in shrimp fed diets supplemented with 2,400, 3,000, 3,600 and 4,500 RE vitamin A/kg, followed by shrimp fed diets with 600 and 1,200 RE vitamin A/kg and finally the unsupplemented control group. Shrimp fed diets supplemented with vitamin A had significantly higher survival percentages than those fed the unsupplemented control diet. Weight gain percentage of the shrimp analyzed by broken-line regression indicated that the minimal dietary vitamin A concentration in growing P. monodon is 2,511 RE/kg ( approximately 8, 400 IU/kg). [ABSTRACT FROM AUTHOR]

The effect of chitin, poly-beta-(1 --> 4)-N-acetyl-glucosamine, and chitosan, a polymer of glucosamine obtained by the deacetylation of chitin, on growth and nutrient digestibility was studied in grass shrimp, Penaeus monodon. Shrimp were fed for 8 wk diets containing no supplement (control) or 2, 5 or 10 g/100 g chitin or chitosan. Each diet was fed to triplicate groups of shrimp with a mean initial body weight of 0.45 +/- 0.05 g. Significantly higher body weight gains were observed in shrimp fed the 5% chitin diet than in those fed the 10% chitin or the control diet. The weight gain of shrimp decreased as dietary chitosan supplementation level increased (r = 0. 87, P < 0.05). Feed efficiencies (FE) and protein efficiency ratios (PER) followed the same pattern. Lower protein and lipid digestibilities and lower body protein and lipid contents were observed in shrimp fed all chitosan-containing diets than in controls (P < 0.05). Carbohydrate digestibility was lower in shrimp fed the 10% chitosan diet than in those fed the control diet. Lower protein and lipid digestibilities, body lipid content and blood cholesterol concentration were observed in shrimp fed the 10% chitin diet compared with controls (P < 0.05). Higher weight gains, body lipid contents and blood cholesterol concentrations were observed in shrimp fed the 2 and 5% chitin diets than in those fed the chitosan diets. Shrimp fed the 5% chitin diet had higher protein and lipid digestibilities and higher body protein content than those fed the 5% chitosan diet (P < 0.05). These data suggest that dietary chitin, supplemented at 5%, enhances P. monodon growth, whereas chitosan depresses shrimp growth, regardless of the supplementation level. [ABSTRACT FROM AUTHOR]

A feeding trial was conducted to estimate the minimal dietary pantothenic acid (PA) requirement for juvenile grass shrimp, Penaeus monodon. Purified diets with seven levels (0, 20, 40, 60, 120, 240, and 480 mg/kg) of supplemental PA were fed to P. monodon (mean weight 0.88 +/- 0.01 g) for 8 wk. The level of PA detected in the unsupplemented diet was 0.02 mg/kg. Each diet was fed to three replicate groups of shrimp. Feed efficiencies (FE) and protein efficiency ratios were highest in shrimp fed the diets supplemented with 120, 240, and 480 mg PA/kg diet, followed by the groups fed 60 mg/kg, then 40 mg/kg, and finally the unsupplemented control group (P < 0.05). Shrimp fed diets supplemented with PA had significantly higher survival percentages and lower hepatopancreatic lipid concentration than those fed the unsupplemented, control diets. Broken-line regression analyses of weight gain percentage and hepatopancreatic CoA and PA concentrations of the shrimp indicated that the adequate dietary PA concentration in growing P. monodon is 101-139 mg/kg. [ABSTRACT FROM AUTHOR]

A feeding trial was conducted to estimate the minimal dietary biotin requirement for juvenile grass shrimp, Penaeus monodon. Purified diets with eight levels (0, 0.2, 0.5, 1.0, 3.0, 6.0, 10.0 and 20.0 mg/kg) of supplemental biotin were fed to P. monodon (mean weight 0. 26 +/- 0.01 g) for 8 wk. Each diet was fed to three replicate groups of shrimp. Shrimp fed diets supplemented with biotin (0.2-20.0 mg/kg) had significantly (P < 0.05) higher weight gain, feed efficiency and protein efficiency ratio than those fed the unsupplemented control diet. Weight gain was high in shrimp fed 3. 0-10.0 mg biotin/kg diet and lowest in shrimp fed

Background: Infants who are HIV-exposed and uninfected have suboptimal growth patterns compared to those who are HIV-unexposed and uninfected. However, little is known about how these patterns persist beyond 1 year of life., Objectives: This study aimed to examine whether infant body composition and growth trajectories differed by HIV exposure during the first 2 years of life among Kenyan infants using advanced growth modeling., Methods: Repeated infant body composition and growth measurements (mean: 6; range: 2-7) were obtained from 6 weeks to 23 months in the Pith Moromo cohort in Western Kenya (n = 295, 50% HIV-exposed and uninfected, 50% male). Body composition trajectory groups were fitted using latent class mixed modeling (LCMM) and associations between HIV exposure and growth trajectories were examined using logistic regression analysis., Results: All infants exhibited poor growth. However, HIV-exposed infants generally grew suboptimally than unexposed infants. Across all body composition models except for the sum of skinfolds, HIV-exposed infants had a higher likelihood of belonging to the suboptimal growth groups identified by LCMM than the HIV-unexposed infants. Notably, HIV-exposed infants were 3.3 times more likely (95% CI: 1.5-7.4) to belong to the length-for-age z-score growth class that remained at a z-score of < -2, indicating stunted growth. HIV-exposed infants were also 2.6 times more likely (95% CI: 1.2-5.4) to belong to the weight-for-length-for-age z-score growth class that remained between 0 and -1, and were 4.2 times more likely (95% CI: 1.9-9.3) to belong to the weight-for-age z-score growth class that indicated poor weight gain besides stunted linear growth., Conclusions: In a cohort of Kenyan infants, HIV-exposed infants grew suboptimally compared to HIV-unexposed infants beyond 1 year of age. These growth patterns and longer-term effects should be further investigated to support the ongoing efforts to reduce early-life HIV exposure-related health disparities., (Copyright © 2022 American Society for Nutrition. Published by Elsevier Inc. All rights reserved.)

A 12-wk feeding trial was conducted to study the influence of chromic oxide (Cr2O3) on carbohydrate utilization and digestibility by tilapia, Oreochromis niloticus x O. aureus. Two levels of chromic oxide (0.5 and 2%) were each incorporated into diets containing glucose or starch. Chromic oxide was added at 0 or 8 wk. The diets were fed to triplicate groups of fish weighing 1.11 +/- 0.05 g. Fish fed the starch diet had greater (P < 0.05) weight gain, feed efficiency ratio, protein efficiency ratio, protein deposition and digestibility of protein, lipid, carbohydrate and dry matter than fish fed the glucose diet irrespective of the time and level of chromic oxide supplementation. Fish fed the glucose diet with 0.5% chromic oxide had higher weight gain, feed efficiency ratio, protein efficiency ratio and protein deposition than fish fed the glucose diet with 2% chromic oxide. The ingredient digestibility estimated using 0.5% chromic oxide as the marker was greater than that estimated with 2% chromic oxide. Higher phosphofructokinase and lower glucose-6-phosphatase activity was found in fish fed the starch diet than in fish fed the glucose diet regardless of the time and level of chromic oxide inclusion. Fish fed the glucose diet with 0.5% chromic oxide had higher phosphofructokinase activity and lower tissue chromium concentration than fish fed the glucose diet with 2% chromic oxide irrespective of chromic oxide inclusion time. These data suggest that the level of chromic oxide in the diet alters glucose utilization by tilapia and affects nutrient digestibility by tilapia. The time of chromic oxide inclusion had no effect on carbohydrate utilization and digestibility.

Two 8-wk experiments were conducted to determine the adequate level of dietary vitamin D for juvenile grass shrimp (Penaeus monodon). In Experiment 1, purified diets with six levels (0, 0.1, 0.5, 2.5, 12.5 and 62.5 mg/kg diet) of supplemental ergocalciferol and cholecalciferol were fed to P. monodon (mean weight 0.19 +/- 0.02 g). In Experiment 2, we used 0, 0.05, 0.1, 0.2, 0.3, 0.6 and 1.0 mg/kg of supplemental cholecalciferol in basal diet fed to the shrimp (mean weight 0.25 +/- 0.03 g). In both experiments, shrimp fed vitamin D-deficient diets grew poorly. In Experiment 1, poorer growth performance was observed in shrimp fed diets containing ergocalciferol compared with those fed the diets containing cholecalciferol. In Experiment 2, weight gain was highest in shrimp fed the diet supplemented with 0.2 mg cholecalciferol/kg diet, followed by the groups fed 0.1 mg/kg, then 0.3 mg/kg, 0.05 and 0.6 mg/kg, 1.0 mg/kg, and finally the unsupplemented control group. The differences among these groups were significant (P < 0.05). The feed efficiency ratio and alkaline phosphatase activity generally followed the same pattern as the weight gain. Analysis by brokenline regression of weight gain and alkaline phosphatase activity of the shrimp in Experiment 2 indicated that the adequate dietary cholecalciferol concentration for growing P. monodon is approximately 0.1 mg/kg.

A feeding trial was conducted to estimate the optimum dietary vitamin K requirement for juvenile marine shrimp, Penaeus monodon. Purified diets with eight levels (0, 5, 10, 20, 50, 80, 160 and 320 mg/kg) of supplemental menadione were fed to P. monodon (mean weight 1.33 +/- 0.05 g) for 12 wk. Each diet was fed to three replicate groups of shrimp. Shrimp fed diets supplemented with vitamin K (5-320 mg/kg) had significantly (P < 0.05) higher weight gain and feed efficiency than those fed the unsupplemented control diet. Shrimp fed diets supplemented with > or = 50 mg/kg vitamin K had higher protein efficiency ratios than shrimp fed the control diet. Calcium deposition in shrimp generally increased as dietary vitamin K supplementation increased. Vitamin K-dependent carboxylase activity was highest in shrimp fed the control diet, followed by shrimp fed 5-160 mg menadione/kg diet, and lowest in those fed 320 mg menadione/kg diet. Vitamin K-dependent protein precursor concentrations were high in shrimp fed 0-10 mg menadione/kg diet, lower in those fed 20 mg/kg, and lowest in shrimp fed > or = 50 mg/kg diet. Protein efficiency ratio and vitamin K-dependent protein precursor concentration analyzed by broken-line regression indicated that the adequate dietary vitamin K concentration in growing P. monodon is 30-40 mg/kg diet.

An experiment was conducted to study the influence of three different forms of chromium (CrCl3.6H2O, Na2CrO4.4H2O and Cr2O3) on the utilization of two carbohydrates (glucose and cornstarch) by juvenile hybrid tilapia (Oreochromis niloticus x O. aureus). Average initial body weight of the fish was 1.13 +/- 0.02 g. Fish were fed 5% body wt/d. Significantly (P < 0.05) greater body weight gain, food intake, protein retention, energy retention and body lipid concentration were observed in fish fed the starch diet than in those fed the glucose diet. Fish fed the glucose diet supplemented with any type of chromium had significantly greater weight gain than those fed the glucose diet without chromium supplementation. Fish fed the glucose diet supplemented with Cr2O3 had greater weight gain, food intake, protein retention, energy retention and body lipid concentration than those fed the unsupplemented glucose diet or the glucose diet supplemented with CrCl3.6H2O or Na2CrO4.4H2O. Delayed plasma glucose peak time was observed in tilapia fed the glucose diet supplemented with any type of chromium. Chromium supplementation generally lowered the glucose-6-phosphatase activity in tilapia. Phosphofructokinase activity was significantly higher in fish fed the glucose diet supplemented with Cr2O3 than in the other glucose-fed groups. These data suggest that chromium supplementation improved glucose utilization by tilapia and that Cr2O3 supplementation was markedly more effective than other chromium forms.

Two 12-wk experiments were conducted to determine the adequate dietary niacin levels for juvenile hybrid tilapia, Oreochromis niloticus x O. aureus, when diets containing either 38% D(+)-glucose or 38% dextrin (type III, from corn) as the carbohydrate source were fed. In Experiment 1, we used 0, 40, 80, 120, 160 and 200 mg/kg of supplemental niacin in both the glucose- and dextrin-containing diets. In Experiment 2, 0, 10, 25, 40 and 55 mg/kg or 0, 10, 25, 40, 80, 120 and 160 mg/kg of supplemental niacin was incorporated in diets containing glucose or dextrin, respectively. In both experiments, fish fed niacin-deficient diets grew poorly. They developed skin, fin and mouth lesions and hemorrhages; the snout was deformed and there was gill edema. These pathologies began 6 wk after the experiments started. Plasma glucose concentrations were higher in fish fed glucose diets than those fed dextrin diets. Weight gain analyzed by broken-line regression indicated that the adequate dietary niacin level for maximal growth in rapidly growing tilapia fingerlings is 26 mg/kg in fish fed the glucose diet and 121 mg/kg in fish fed the dextrin diet.

Mucinase and beta-glucuronidase enable colon bacteria to degrade protective mucins and recycle glucuronide conjugates of toxins and carcinogens. The response of these bacterial enzymes to dietary fiber was studied in the laboratory rat. Fiber-free basal diet was mixed with guar gum, pectin, carrageenan, or cellulose at levels of 5 and 15%. These diets were fed for 21 days to groups of six male Fischer-344 rats having an average weight of 150 g. Mucinase and beta-glucuronidase activities were assayed in fresh rat feces. Rats fed 15% guar gum or pectin gained significantly (P less than 0.05) less weight than the other rats. Mucinase specific activity was highest in the fiber-free diet group and lowest in the 15% guar gum group. Total daily output of mucinase was highest in rats fed fiber-free diet or cellulose and lower in rats fed more readily fermentable fiber. Specific activity and total output of beta-glucuronidase were highest in rats fed fiber-free diet and significantly lower in those fed 15% fiber diets. These data are consistent with the hypothesis that some kinds of dietary fiber may play a role in the etiology of intestinal disease.

Apparent intestinal permeability was determined indirectly by orally administering a poorly absorbed dye, phenol red, to rats and measuring its recovery in feces and in urine. Increased apparent permeability was recognized by increased dye recovery in urine and by an increased ratio of urinary to fecal dye recovery. Guar gum, pectin, carrageenan type I (80% kappa, 20% lambda), carrageenan type II (iota) and cellulose were each fed at levels of 5 and 15% (wt/wt) of the diet for 31 d to male Fischer 344 rats. The average initial weight of rats was 230 g. Rats fed 15% guar gum gained significantly less weight than most of the other rats (P less than 0.05). Phenol red recovery was measured at 2 and 4 wk after the beginning of the experiment. At 2 wk urinary recoveries of phenol red were high in rats fed fiber-free and carrageenan type II diets, indicating increased apparent permeability. By 4 wk, adaptation had apparently taken place. Urinary dye recoveries were lower in every diet group, and most fiber-containing diet groups gave significantly lower recoveries than did the fiber-free group. Fecal recovery of phenol red was high in the cellulose, carrageenan I, and 5% carrageenan II groups, intermediate in the 5% pectin and 15% carrageenan II groups, and low in the fiber-free, guar gum and 15% pectin groups at both 2 and 4 wk. The ratio of phenol red recovery from urine to that from feces, another index of apparent intestinal permeability, was higher in the fiber-free diet group than in all the other groups. Rats fed 15% dietary fiber had higher average ratios than those fed the same fiber at 5%. These data are consistent with the hypothesis that intestinal permeability to foreign substances may be altered considerably by diet.