Effect Of Dietary Chitosan Research Articles

Effects of Dietary Chitosan on Growth Performance, Serum Biochemical Indices, Antioxidant Capacity, and Immune Response of Juvenile Tilapia (Oreochromis niloticus) under Cadmium Stress.

The objective of this study was to examine the effects of varying levels of dietary chitosan supplementation on mitigating cadmium stress and its influence on growth performance, serum biochemical indices, antioxidant capacity, immune response, inflammatory response, and the expression of related genes in juvenile Genetically Improved Farmed Tilapia (GIFT, Oreochromis niloticus). Five groups of juvenile tilapias (initial body weight 21.21 ± 0.24 g) were fed five diets with different levels (0%, 0.5%, 1.0%, 1.5%, and 2.0%) of chitosan supplementation for 60 days under cadmium stress (0.2 mg/L Cd2+). The findings indicated that, compared with the 0% chitosan group, dietary chitosan could significantly increase (p < 0.05) the final weight (Wf), weight gain rate (WGR), specific growth rate (SGR), daily growth index (DGI), and condition factor (CF), while the feed conversion ratio (FCR) expressed the opposite trend in juvenile GIFT. Dietary chitosan could significantly increase (p < 0.05) the activities (contents) of cholinesterase (CHE), albumin (ALB), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), acid phosphatase (ACP), and lysozyme (LZM), while glutamic pyruvic transaminase (GPT), glutamic oxaloacetic transaminase (GOT), and complement 3 (C3) in the serum of juvenile GIFT expressed the opposite trend. Dietary chitosan could significantly increase (p < 0.05) the activities of superoxide dismutase (SOD) and catalase (CAT) and significantly decrease (p < 0.05) the activities (contents) of glutathione S-transferase (GST), glutathione peroxidase (GSH-Px), and malondialdehyde (MDA) in the serum of juvenile GIFT. Dietary chitosan could significantly increase (p < 0.05) the activities (contents) of CAT, GST, GSH-Px, and total antioxidant capacity (T-AOC) and significantly decrease (p < 0.05) the contents of MDA in the liver of juvenile GIFT. Dietary chitosan could significantly increase (p < 0.05) the activities (contents) of SOD, GSH-Px, T-AOC, Na+-K+-ATPase, and Ca2+-ATPase and significantly decrease (p < 0.05) the activities (contents) of CAT, GST, and MDA in the gills of juvenile GIFT. Dietary chitosan could significantly up-regulate (p < 0.05) the gene expression of cat, sod, gst, and gsh-px in the liver of juvenile GIFT. Dietary chitosan could significantly up-regulate (p < 0.05) the gene expression of interferon-γ (inf-γ) in the gills and spleen and significantly down-regulate (p < 0.05) the gene expression of inf-γ in the liver and head kidney of juvenile GIFT. Dietary chitosan could significantly down-regulate (p < 0.05) the gene expression of interleukin-6 (il-6), il-8, and tumor necrosis factor-α (tnf-α) in the liver, gills, head kidney, and spleen of juvenile GIFT. Dietary chitosan could significantly up-regulate (p < 0.05) the gene expression of il-10 in the liver, gills, head kidney, and spleen of juvenile GIFT. Dietary chitosan could significantly up-regulate (p < 0.05) the gene expression of transforming growth factor-β (tgf-β) in the liver and significantly down-regulate (p < 0.05) the gene expression of tgf-β in the head kidney and spleen of juvenile GIFT. In conclusion, dietary chitosan could mitigate the impact of cadmium stress on growth performance, serum biochemical indices, antioxidant capacity, immune response, inflammatory response, and related gene expression in juvenile GIFT. According to the analysis of second-order polynomial regression, it was found that the optimal dietary chitosan levels in juvenile GIFT was approximately 1.42% to 1.45%, based on its impact on Wf, WGR, SGR, and DGI.

Effect of dietary chitosan on the growth performance, intestinal histology and growth-related gene expression in stellate sturgeon (Acipenser stellatus) juveniles.

As sturgeon breeding has proliferated, there has been a heightened demand for growth stimulators in their diets. This study aimed to determine the impact of dietary chitosan on growth performance, whole-body proximate composition, growth-related gene expression, and intestinal histology in juvenile Acipenser stellatus. A total of 180 A. stellatus juveniles with an average weight of 31.90 ± 0.73 g were fed with diets containing 0 (control), 1.5, 3.0, 4.5, and 6.0 g chitosan.kg-1 basic diet for eight weeks. The findings revealed a significant enhancement in growth performance with rising chitosan concentrations. Furthermore, chitosan supplementation upregulated the expression of the growth hormone gene in both brain and liver tissues. In liver samples, the most pronounced expression of the insulin-like growth factor-1 gene was noted at 6.0 g chitosan.kg-1, while in brain samples, peak expressions were observed in both the 4.5 and 6.0 g chitosan.kg-1 treatments. While the whole-body proximate composition remained relatively stable, there was a notable decrease in whole-body lipids with the escalation of chitosan dosage. Intestinal villi dimensions, both height and width, were amplified in the chitosan-supplemented groups compared to controls. In summation, chitosan supplementation showed promise in bolstering growth performance, refining intestinal morphology, and enhancing growth-related gene expression. Analysis of the polynomial regression of weight gain and specific growth rate revealed that the optimum dietary chitosan requirements in A. stellatus were 5.32 and 5.21 g chitosan.kg-1, respectively.

Effects of dietary chitosan on the growth, health status and disease resistance of golden pompano (Trachinotus ovatus)

The effects of dietary chitosan (0, 2, 4, 6, 8 and 10 g/kg) on the growth, health condition and disease resistance of golden pompano Trachinotus ovatus were evaluated. Dietary chitosan significantly enhanced weight gain, with the highest observed in fish fed the 6 g/kg chitosan diet. This chitosan level significantly promoted gut health by increasing villus length, lipase and protease activities and intestinal barrier-related genes expression. Meanwhile, dietary 6 g/kg chitosan improved the inflammatory response and anti-oxidative capacity of fish by regulating the expression of genes involved in NF-κB pathway and Nrf2 pathway, respectively. Furthermore, after challenge with Vibrio harveyi for 2 weeks, the survival rate increased significantly when dietary chitosan level was 6 g/kg. Overall, our results indicate that 6 g/kg chitosan is the optimal dose for enhancing growth, health and disease resistance of fish, but excessive chitosan (10 g/kg) weakens its beneficial effects.

Chitosan Displays a Potent Caloric Restriction Mimetic Effect in Senescent Rats.

Chitosan is a polysaccharide made up of β1,4-linked d-glucosamine (GlcN) and N-acetyl-GlcN. In this study, we evaluated the possible caloric restriction mimetic (CRM) effect of dietary chitosan on systemic redox status, inflammatory biomarkers, and lipid profile in plasma and erythrocyte samples of d-galactose-induced mimetically aged rats. We found a significant increase (p < 0.05) in the reactive oxygen species, protein carbonyl, fasting glucose, body weight, cholesterol, triglyceride, inflammatory markers-interleukin-6 and tumor necrosis factor-alpha in an accelerated senescent rat model. There was also a significant decrease (p < 0.05) in glutathione, advanced glycation end product in senescent rats. Chitosan treatment increased ferric-reducing antioxidant potential, glutathione, plasma membrane-reduced system in accelerated senescent model of rats. Our finding suggests that chitosan has properties similar to a CRM and can effectively maintain the redox homeostasis during the aging process in rat erythrocytes.

The Dietary Chitosan Positively Modulates the Growth and Survival of Barbonymus gonionotus Fry

The dietary chitosan has been largely used in the supplemental diets of terrestrial animals to improve growth and development. However, there is little information on the roles of dietary chitosan in growth and development of aquatic animals like fishes. Thus, this study aimed at determining the effects of dietary chitosan on growth performances and survival of Barbonymus gonionotus fry. A total of 600 B. gonionotus fry (2.12±0.02 g) were considered for this study. This experiment consisted of four treatments (0, 1, 2 and 3 g Kg-1 formulated feeds) and each treatment had three replications with a stocking density of 50 fry/tank. The dietary chitosan was supplied as 8% of body weight of each fry twice daily for 60 days. Fish fry treated with the dietary chitosan exhibited significant (P &lt; 0.05) improvement in growth (body weight gain, % body weight gain, specific growth rate, and feed conversion ratio) and survival of B. gonionotus in comparison with untreated control. The water quality parameters, such as temperature, pH and dissolved oxygen showed no significant variations, and maintained suitable range throughout the study period for fish growth. Among the treatments, application of 1 g chitosan kg-1 feed showed the highest positive effects on growth and survival of B. gonionotus fry, indicating their potentials for practical application in promoting sustainable aquaculture.&#x0D; Ann. Bangladesh Agric. (2020) 24(1) : 41-50

Effect of dietary chitosan on the feed efficiency and weight performance of high fat diet induced hyperlipidemia in male wistar rat

&lt;p class="abstract"&gt;&lt;strong&gt;Background:&lt;/strong&gt; This study was carried out to determine the growth performance of rats fed graded levels of chitosan supplemented High fat diet. &lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Methods:&lt;/strong&gt; Thirty male wistar rats weighing between 70 g and 90 g were purchased and randomly allotted into three (3) treatment groups with graded levels of chitosan in High fat diet (1%, 3% and 5%) and three (3) control groups namely: normal diet, High fat diet and normal diet +5% chitosan. The feed intakes as well as weight change of the experimental rats were monitored for six (6) weeks.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Results:&lt;/strong&gt; The results obtained showed that the highest level of feed intake and feed efficiency were recorded for animals in group fed 5% level of chitosan supplementation when compared to other treatment groups. Similar result was observed for the weight change (as there was significant reduction in the weight gain with increase chitosan supplementation in HFD) which can be attributed to the efficient utilization of feed consumption.&lt;/p&gt;&lt;p class="abstract"&gt;&lt;strong&gt;Conclusions:&lt;/strong&gt; It can be concluded that dietary chitosan prevents excess weight gain in hyperlipidemia and improves the overall nutritional attributes of the experimental diets by improving their feed efficiencies as compared to the control.&lt;/p&gt;

Effects of dietary chitosan and nano-chitosan loaded clinoptilolite on growth and immune responses of rainbow trout (Oncorhynchus mykiss)

In this study, rainbow trout Oncorhynchus mykiss weighing 27.75 ± 0.34 g were orally subjected to eight experimental diets each in three replicates containing varying amounts of chitosan and nano-chitosan (0.05, 0.5 and 5 g kg−1) loaded in clinoptilolite (14.28 g kg−1) for 70 days; and the growth and immune responses were evaluated. Results showed that growth parameters in fish fed diets chit + clin2, chit + clin3, nchit + clin1, nchit + clin2 and nchit + clin3 were significantly higher than in fish fed the control diet. All feeds, except chit + clin3, and nchit + clin3, significantly increased the total protein level. Feeds containing chit + clin2, nchit + clin1, and nchit + clin2 significantly elevated serum lysozyme activity compared with the control group. All treatments, except chit + clin3, and nchit + clin3 exhibited higher serum immunoglobulin (Ig) level than control one. In contrast, diet nchit + clin1 significantly unregulated the expression of Ig M gene in fish head-kidney compared to other groups. Additionally, all feeds, except clinoptilolite, and nchit + clin3, significantly improved the serum complement activity. Diets chit + clin2, nchit + clin1, and nchit + clin2 also significantly elevated antibacterial activity against Yersinia ruckeri compared with the control diet. Expression of inducible nitric oxide synthase (iNOS) gene in fish fed diets clinoptilolite, chit + clin1, chit + clin3, nchit + clin1, nchit + clin2, and nchit + clin3 was significantly higher than the control diet. All diets, except clinoptilolite, increased IL-1β gene expression compared to the control group. Present results suggest that diets supplemented with nchit + clin, especially at 0.05 g kg−1 nano-chitosan inclusion, could improve growth performance and immune parameters of rainbow trout.

Effect of Dietary Chitosan, Nano-Chitosan Supplementation and Different Japanese Quail Lines on Growth Performance, Plasma Constituents, Carcass Characteristics, Antioxidant Status and Intestinal Microflora Population

Effect of Dietary Chitosan, Nano-Chitosan Supplementation and Different Japanese Quail Lines on Growth Performance, Plasma Constituents, Carcass Characteristics, Antioxidant Status and Intestinal Microflora Population

Effects of dietary chitosan on growth rate, small intestinal morphology, nutrients apparent utilization and digestive enzyme activities of growing Huoyan geese

Dietary chitosan (CS) supplementation could improve the growth rate, small intestinal morphology, nutrients apparent digestibility and digestive enzyme activities in pigs, broiler chickens, rats and fish, whereas no data has been reported about the effect of CS on the growing Huoyan geese. Therefore, this study was designed to investigate the effects of CS on growth rate, small intestinal morphology, nutrients apparent utilization and digestive enzyme activities of growing Huoyan geese. Three hundred and twenty (28 days of age, gender balance) Huoyan geese were randomly divided into control, CS100, CS200 and CS400 groups (based on BW) with 20 geese per pen and 4 replicates pen per group, and the feeding experiment lasted for 4 weeks. The 4 diets contained 0, 100, 200 and 400 mg CS per kg feed, respectively. The results showed that CS200 groups had higher average daily gain, final BW, apparent utilization of DM and CP, and lower feed/gain ratio compared with the control group (P < 0.05). Meanwhile, CS100 and CS200 groups had higher villus height, villus height/crypt depth ratio and lower crypt depth in duodenum and jejunum than those in the control group (P < 0.05). The geese in CS100 and CS200 groups had higher villus height, villus height/crypt depth ratio and lower crypt depth of ileum compared with those in control and CS400 groups (P < 0.05). In addition, compared with the control group, CS200 group has higher trypsin activities and lower lipase activities in duodenal, jejunal and ileal contents (P < 0.05). The results suggested that addition of 200 mg/kg CS had positive effects on growth rate, small intestinal morphology, nutrients apparent utilization and digestive enzyme activities of growing Huoyan geese.

Effects of Dietary Chitosan and Probiotics on the Quality and Physicochemical Characteristics in Hanwoo Striploin

Effects of Dietary Chitosan and Probiotics on the Quality and Physicochemical Characteristics in Hanwoo Striploin

Effect of dietary chitosan on challenged Dicentrarchus labrax post larvae with Aeromonas hydrophila

Effect of different dietary squilla chitosan (Csq) concentrations: 0 (control), 0.5, 1 and 2 g 100 g–1 diets were studied for weaned sea bass (Dicentrarchus labrax) post larvae. Post larvae were challenged with Aeromonas hydrophila after 5 feeding days, in order to monitor the prophylactic effect on the Csq fed larvae. The experiment started with an average initial weight of 50 ± 2 mg and total length of 12 ± 2 mm for post larval stage (40 days post hatch; dph), then continued feeding diets for a period of 20 days. Larvae survival percentage (%), mean total length (TL), width (W), total weight (TW), total weight gain (TWG), average daily weight (ADW) and specific growth rate (SGR) were recorded as morphometric measurements representing growth compared to the control groups. The results revealed that 1g Csq 100 g–1 diet at P < 0.05 was the most effective concentration that achieved higher survival percentages; 94.5 ± 0.5 and 74 ± 2.0%, increasing the specific growth rate by 7.22% and 5.77% for non challenged and challenged weaned larval groups, respectively. Otherwise, the control challenged group displayed the lowest performance in all assayed parameters with the coincidental decrease in the survival % and specific growth rates. Similarly, lower growth performance was also observed at 2 g 100 g–1 diet. Thus, the incorporation of chitosan at a level of 1g in fish diet enhanced the performance and reduced the fish mortality under stress conditions.

Effect of dietary chitosan on immune response and disease resistance in Cyprinus carpio

BACKGROUND: Occurrence of resistance against antibiotics and inadequate efficacy of some vaccines necessitates studies of natural immunostimulators in aquaculture. Shrimps shell derived from Chitosan can be used as immune stimulators in fish. OBJECTIVES: In this study, the effects of oral administration of chitosan, derived from shrimp shell, on some immune responses and disease resistance in Cyprinus carpio were studied. METHODS: Three hundred healthy fish weighing 42.4+8.1 g were divided into 4 equal groups: the first group (G10) was fed with food supplemented with 10 mg kg -1 chitosan, the second (G5) and third groups (G2.5) were fed with food supplemented with 5 mg kg -1 and 2.5 mg kg -1 , respectively. The control group was fed with basal feed (without chitosan). All groups were treated for 60 days. Blood samples were taken on 0, 20, 40, and 60 days post- experiment; In addition, some immunological indices, including serum lysozyme activity, serum bactericidal activity, Nitro Blue Tetrazolium (NBT) reduction activity, serum proteins, white blood cell count (WBC), and differentiated count were measured. At the end of the treatment, fish were challenged with live Aeromonas hydrophila and mortality rate was recorded for 14 days. RESULTS: Oral administration of chitosan (0.5 and 1%) significantly enhanced NBT reduction activity and resistance to A. hydrophila infection (p=0.012). Serum lysozyme and bactericidal activity, serum total protein and globulin, WBC and leukocytes ratio showed no significant change among the groups (p>0.05). CONCLUSIONS: This study indicates that oral administration of shrimp shell chitosan may have a positive effect on some immune parameters and resistance against bacterial infection in Cyprinus carpio.

Chitosan and its oligosaccharide derivatives (chito-oligosaccharides) as feed supplements in poultry and swine nutrition.

Chitosan is a non-toxic polyglucosamine, widespread in nature, which is deacetylated to varying degrees form of chitin, a component of exoskeleton of shrimps, crabs and insects. Because chitosan contains reactive functional groups, that is, amino acids and hydroxyl groups, it is characterised by antimicrobial, anti-inflammatory, anti-oxidative, antitumor, immunostimulatory and hypocholesterolemic properties when fed as dietary additive for farm animals. This article reviews and discusses the results of studies on the effects of dietary chitosan and its oligosaccharide derivatives on performance and metabolic response in poultry and pigs, that is, haematological, biochemical and immunological blood characteristics, microbiological profile of intestines, intestinal morphology and digestibility of nutrients, as well as on the quality of meat and eggs. The results of most of the experiments presented in this review indicate that chitosan used as a feed additive for poultry and pigs has some beneficial, biological effects, including immunomodulatory, anti-oxidative, antimicrobial and hypocholesterolemic properties. These properties of chitosan, unlike many other kinds of feed additives, were often reflected in improved growth performance (body weight gain and/or feed conversion ratio) of young animals, that is, broiler chickens and weaned pigs.

Effects of Dietary Chitosan on Hormone Level in Dairy Calves

Effects of Dietary Chitosan on Hormone Level in Dairy Calves

Effects of dietary supplementation of chitosan on growth performance and immune index in ducks

The effect of dietary chitosan on growth performance and immune index were investigated in ducks. One-day-old ducks were fed on a control diet or diets containing 0.00, 0.30, 0.60, 1.20, 2.40 and 4.80 g/kg of 85.20% deacetylated chitin (chitosan) or 0.45 g/kg aureomycin for 35 days. The results indicate that the ducks in 1.20 g/kg dietary chitosan group had the superior average daily body gain, average daily feed intake and feed conversion ratios, while the weight of immune organ and body weight adjusted weights for immune organs in 2.40 g/kg dietary chitosan group were higher than those in other groups. Also, lymphocyte proliferation of 1.20 and 2.40 g/kg were higher than those of other groups. It was concluded that 1.20 and 2.40 g/kg dietary chitosan were suitable for ducks to gain a better growth performance and immune function. Key words: Chitosan, ducks, growth performance, immune function.

Effects of dietary chitosan and Bacillus subtilis on the growth performance, non-specific immunity and disease resistance of cobia, Rachycentron canadum

The present study was performed to investigate the effects of various levels of dietary Bacillus subtilis and chitosan on the growth performance, non-specific immunity and protection against Vibrio harveyi infection in cobia, Rachycentron canadum. Fish were fed with the control diet and six different experimental diets containing three graded levels of B. subtilis at 2 × 10 10 CFU g −1 (0.0, 1.0, 2.0 g kg −1 diet) for each of two levels of chitosan (3.0 and 6.0 g kg −1 diet). The results of 8 weeks feeding trial showed that the survival rate ranged from 81.3% to 84.0% with no significant difference ( P > 0.05). The SGR (%) in the fish fed with dietary treatments was significantly higher than that of the control fish except diet 6 group with 2.0 g kg −1 B. subtilis and 3.0 g kg −1 chitosan. The serum lysozyme activities were significantly higher in 6.0 g kg −1 chitosan groups and no significant differences were observed among B. subtilis levels. The serum ACP activities were significantly higher in 3.0 g kg −1 chitosan groups at 0.0 and 1.0 g kg −1 B. subtilis levels; at low chitosan level, the cobia fed diets with 1.0 g kg −1 B. subtilis had significantly higher serum ACP activity, but at high chitosan level, the cobia fed diets with 2.0 g kg −1 B. subtilis had significantly higher serum ACP activity. The phagocytosis and respiratory burst activity in the fish fed with dietary treatments was significantly higher than that of the control fish except diet 3 group with 6.0 g kg −1 chitosan. Moreover, fish fed the diet containing 2.0 g kg −1 B. subtilis and 6.0 g kg −1 chitosan had significantly higher post-challenge survival on the 7th day following V. harveyi infection and post-challenge survival showed clearly the synergistic effect of chitosan and B. subtilis. Based on these results, the combination of 1.0 g kg −1 B. subtilis and 6.0 g kg −1 chitosan is optimal for the growth, innate immunity and disease resistance of cobia with an 8-week oral administration.

Effects of dietary chitosan on growth, survival and stress tolerance of postlarval shrimp, Litopenaeus vannamei

The effect of chitosan, a polymer of glucosamine obtained by the deacetylation of chitin, on growth, survival and stress tolerance was studied in postlarval Litopenaeus vannamei. An experiment was performed with postlarval shrimp (mean initial wet weight 1.2 mg) fed five isoenergic and isonitrogenous diets containing five supplemented levels of chitosan (0, 0.5, 1, 2 and 4 g kg−1 diet, respectively). The five compound diets (C0, C0.5, C1, C2 and C4) sustained shrimp growth throughout the experiment. Growth performance (final body weights; weight gain; SGR: specific growth rate) in shrimp fed diet C2 was significantly higher than that in shrimp fed diets C0, C0.5 and C1 (P < 0.05), diet C4 treatment provided intermediate growth result. The survival in shrimp fed diet C1 was significantly higher than that in shrimp fed C0 diet (P < 0.05), other diets treatments gave the intermediate survival results. No significant differences were found in growth and survival between diet C2 and C4 treatments. After 9 days of a stress tolerance test, survival in shrimp fed diets C1, C2 and C4 was significantly higher than that in shrimp fed diets C0 and C0.5. We concluded from this experiment that the incorporation of a moderate dietary chitosan was beneficial to the development of postlarval L. vannamei. Considering the effect of chitosan on both growth and survival of postlarval L. vannamei, second-degree polynomial regression of SGR and survival indicated optimum supplement of dietary chitosan at 2.67 and 2.13 g kg−1, respectively, so the level of chitosan supplemented in the diet should be between 2.13 and 2.67 g kg−1.

The Effect of Dietary Chitosan and Chitin Supplementation on the Survival and Immune Reactivity of Crayfish, Procambarus clarkii

White spot syndrome virus (WSSV) is an important viral pathogen responsible for severe economic loss to shrimp aquaculture. The effect of oral administration of chitosan and chitin against WSSV in crayfish Procambarus clarkii was investigated. Six groups of 20 crayfish, P. clarkii, in triplicate were diet supplemented with chitosan or chitin at 5, 10, and 15 mg/g for 4 wks, and orally challenged with WSSV. The cumulative mortalities in the groups fed with chitosan at 10 mg/g was significantly lower (P &lt; 0.05) than the control but the other groups were not. The relative percent survival (RPS) showed that chitosan provided better protection against WSSV than chitin (P &lt; 0.05). Polymerase chain reaction (PCR) analysis showed that the surviving crayfish were WSSV negative. The immunological parameters analyzed revealed that the crayfish fed with chitosan and chitin showed significantly higher level of total hemocyte count (THC), prophenoloxidase (proPO), and superoxide dismutase (SOD) when compared to the control groups.

Effects of dietary chitosan on fat deposition and lipase activity in digesta in broiler chickens

1. The effect of dietary chitosan on fat deposition and lipase activity in the small intestinal contents was investigated in broiler chickens fed an adequate or high metabolisable energy (ME) diet. 2. Male broiler chickens at 14 d old were fed on the adequate or high ME diet supplemented with 0 or 50 g/kg chitosan, which has a low viscosity, for 3 weeks. 3. Dietary chitosan did not affect food intake, body weight gain or food efficiency in either dietary ME groups. 4. Dietary chitosan reduced the excessive abdominal fat deposition induced by the high ME diet. 5. Dietary chitosan increased the weight of intestinal concentration. 6. Dietary chitosan decreased the lipase activity per g of small intestinal contents. 7. These results suggest that dietary chitosan with low viscosity decreases lipase activity and fat absorption in the small intestine, consequently resulting in a reduction of fat deposition in broiler chickens. 8. It was concluded that dietary chitosan with low viscosity can decrease body fat deposition without reducing food intake and body weight gain in broiler chickens. contents irrespective of dietary ME

The influence of high and low molecular weight chitosan on colonic cell proliferation and aberrant crypt foci development in CF1 mice

The effect of dietary chitosan, a fibre of animal origin, on the induction and development of colonic precursor lesions was determined in CFl mice. Over a 2-wk pretreatment period, one group of mice was given azoxymethane (four injections of 5 mg/kg body weight) and the other was treated with saline. Subsequent to carcinogen or saline pretreatment mice were randomized into one of three dietary groups: (i) control AIN-76 diet; (ii) control AIN-76 diet with 2% low molecular weight chitosan (LMWC); or (iii) control AIN-76 diet with 2% high molecular weight chitosan (HMWC). Mice were maintained on this diet for 6 wk. Mice fed diet containing HMWC had significant reductions in the number of aberrant crypt foci, cell proliferation, crypt height and crypt circumference in the colonic epithelium ( P < 0.05). In mice given diet supplemented with LMWC there was a trend towards reduced numbers of aberrant crypts, as well as decreased crypt height and circumference. The results of this study indicate that dietary chitosan reduces the incidence of early preneoplastic markers of colon carcinogenesis, as indicated by aberrant crypts and mitotic figures and altered crypt morphometrics in the murine colon. Molecular range and viscosity of the chitosan may influence the efficacy of this activity.