77 research outputs found

    Influence of genotype and feeding on chemical composition of organi chicken meat

    Get PDF
    The aim of this study was to evaluate the effects of different genotypes and of feeding on meat chemical composition, including fatty acid profile, of chickens reared under organic conditions. Two meat–type fast-growing (FG) and medium-growing (MG), and one egg-type slow-growing (SG) strains were assigned to 2 different diets differing for the protein source: soybean (SB) and faba bean (FB) in partial substitution of soybean. Genotype markedly affected the meat chemical composition. SG breast and thigh meat showed lower content of lipids (P<0.01) than FG. The highest proportions of polyunsaturated fatty acids (PUFA) n-6 and n-3 and the lowest proportion of monounsaturated (MUFA) (P<0.01), as well as the lowest ratio of PUFA n6/n3 (P<0.01) were found in SG breast and thigh meat. MG showed always intermediate values. As for feeding, FB treatment produced only a slight increment of protein in breast and a decrease of fat and ash in thigh meat. Total PUFA and PUFA n-6 resulted lower in both thigh and breast meat of FB groups compared to SB (P<0.01)

    Effects of dietary supplementation with krill meal on pigmentation and quality of flesh of rainbow trout (Oncorhynchus mykiss)

    Get PDF
    Effects of administration of krill meal and synthetic astaxanthin during the finisher phase of the fattening cycle of rainbow trout on flesh pigmentation and quality traits were studied. The inclusion of krill meal increased the body weight and size and decreased the peri-visceral fat and visceral weight indices. The astaxanthin diet produced the highest accumulation of total carotenoids in the fillet compared to the krill meal diet: the difference was significant after 15 days of feeding (2.50 vs 2.10 mg/kg) till the end of the trial (5.00 vs 4.80 mg/kg). The same pattern was observed for astaxanthin concentration with the highest values in the fillets of fish fed the astaxanthin diet. Fillet lightness (L*) was not affected by trout diets whereas redness (a*) and yellowness (b*) were significantly higher in fish fed the astaxanthin diet until day 30 of the trial. Hue was not affected by feeding, whereas chroma was significantly higher in the fish fed astaxanthin throughout the trial except on day 45 of sampling. Trout fed the krill meal diet had a paler pink-red colour on the SalmoFan scale than those receiving the astaxanthin diet. No significant differences emerged in proximate composition and cholesterol content of trout in the two groups. The fatty acid profile of the fillets reflected the fatty acids of the diets administered to the trout: eicosapentaenoic, docosahexaenoic and docosapentaenoic acids and total n-3 polyunsaturated fatty acids were significantly higher in the fish fed the krill meal

    Effect of dietary supplementation with Lactobacillus acidophilus D2/CSL (CECT 4529) on caecum microbioma and productive performance in broiler chickens

    Get PDF
    This study examines the effects of the dietary supplementation with Lactobacillus acidophilus D2/CSL (CECT 4529) (LA) on productive performances, incidence of foot pad dermatitis and caecum microbioma in broiler chickens. A total of 1,100 one-day old male Ross 308 chicks were divided into 2 groups of 16 replicates with 25 birds each and reared from 1-41 d. One group was fed a basal diet (CON) and the other group the same diet supplemented with LA. Caecum contents were collected from 4 selected birds at day one and 5 selected birds at the end of the rearing period. Then, they were submitted to DNA extraction and whole DNA shotgun metagenomic sequencing. Overall, the LA supplementation produced a significant beneficial effect on body weight gain between 15-28 d and improved feed conversion rate in the overall period. On the contrary, litter moisture, pH and incidence of the foot pad lesions were not affected by LA. Birds treated with LA showed a lower occurrence of pasty vent at both 14 and 28 d. At the end of the rearing period, Lachanospiraceae were significantly higher in LA birds in comparison to CON (17.07 vs 14.39%; P = 0.036). Moreover, Ruminococcus obeum, Clostridium clostridioforme, Roseburia intestinalis, Lachnos-piraceae bacterium 14-2T and Coprococcus eutactuswere significantly higher in LA birds in comparison to CON. The relative abundance of Lactobacillus acidophilus was comparable between LA and CON groups. However, a positive effect was observed in relation to the metabolic functions in the treated group, with particular reference to the higher abundance of \u3b2-glucosidase. In conclusion, the LA supplementation improved broiler productive performances and metabolic functions promoting animal health

    Feeding broiler chickens with arginine above recommended levels: effects on growth performance, metabolism, and intestinal microbiota

    Get PDF
    BackgroundArginine is an essential amino acid for chickens and feeding diets with arginine beyond the recommended levels has been shown to influence the growth performance of broiler chickens in a positive way. Nonetheless, further research is required to understand how arginine supplementation above the widely adopted dosages affects metabolism and intestinal health of broilers. Therefore, this study was designed to assess the effects of arginine supplementation (i.e., total arginine to total lysine ratio of 1.20 instead of 1.06-1.08 recommended by the breeding company) on growth performance of broiler chickens and to explore its impacts on the hepatic and blood metabolic profiles, as well as on the intestinal microbiota. For this purpose, 630 one-day-old male Ross 308 broiler chicks were assigned to 2 treatments (7 replicates each) fed a control diet or a crystalline L-arginine-supplemented diet for 49 d.ResultsCompared to control birds, those supplemented with arginine performed significantly better exhibiting greater final body weight at D49 (3778 vs. 3937 g; P &lt; 0.001), higher growth rate (76.15 vs. 79.46 g of body weight gained daily; P &lt; 0.001), and lower cumulative feed conversion ratio (1.808 vs. 1.732; P &lt; 0.05). Plasma concentrations of arginine, betaine, histidine, and creatine were greater in supplemented birds than in their control counterparts, as were those of creatine, leucine and other essential amino acids at the hepatic level. In contrast, leucine concentration was lower in the caecal content of supplemented birds. Reduced alpha diversity and relative abundance of Firmicutes and Proteobacteria (specifically Escherichia coli), as well as increased abundance of Bacteroidetes and Lactobacillus salivarius were found in the caecal content of supplemented birds.ConclusionsThe improvement in growth performance corroborates the advantages of supplementing arginine in broiler nutrition. It can be hypothesized that the performance enhancement found in this study is associated with the increased availability of arginine, betaine, histidine, and creatine in plasma and the liver, as well as to the ability of extra dietary arginine to potentially ameliorate intestinal conditions and microbiota of supplemented birds. However, the latter promising property, along with other research questions raised by this study, deserve further investigations

    Effect of a low protein diet on chicken ceca microbiome and productive performances

    Get PDF
    ABSTRACT The aim of this study was to investigate the impact of supplementation of a low protein diet on ceca microbiome and productive performances of broiler chickens. A total of 1,170 one-day-old male chicks (Ross 308) were divided in 2 diet groups and reared in the same conditions up to 42 D. Birds belonging to the control group were fed a basal diet. Birds belonging to the low protein group the basal diet with a reduced level of crude protein (–7%). Cecum contents from randomly selected birds were collected at 14 and 42 D within each diet group, submitted to DNA extraction and then tested by shotgun metagenomic sequencing. Abundances of species belonging to Actinobacteria and Proteobacteria were mainly affected by the diet as well as interaction between diet and time, while species belonging to Firmicutes and Cyanobacteria changed mainly according to the age of the birds. At family level, Lactobacillaceae significantly decreased in the low protein group up to 14 D. However, at the end of the rearing period the same family was significantly higher in the low protein group. The most abundant functional genes, represented by cystine desulfurase, alpha-galactosidase, and serine hydroxymethyltransferase, displayed comparable abundances in both diet groups, although significative differences were identified for less abundant functional genes at both sampling times. Birds fed control and low protein diets showed similar productive performances. However, in the finisher phase, feed conversion rate was significantly better in chickens fed the low protein diet. Overall, this study showed that a reduced intake of crude protein in broilers increases the abundance of Lactobacillaceae in the ceca over time and this seems to be linked to a better feed conversion rate between 36 and 42 D. A reduced intake of crude protein in chicken production can help to improve exploitation of edible resources, while reducing the emission of nitrogen pollutants in the environment

    Metabolic and microbiota response to arginine supplementation and cyclic heat stress in broiler chickens

    Get PDF
    Little attention has been paid to the biological role of arginine and its dietary supplementation in broilers under heat stress (HS) conditions. Therefore, the main aim of this study was to assess the response of broilers to arginine supplementation and cyclic HS, with a focus on liver, pectoral muscle, and blood metabolic profiles and the cecal microbiota. Day-old male Ross 308 broilers (n = 240) were placed in 2 rooms with 12 pens each for a 44-day trial. Pens were assigned to one of two groups (6 pens/group/room): the control group (CON) was given a basal diet in mash form and the treated group (ARG) was fed CON diet supplemented with crystalline L-arginine. The total arginine:lysine ratio of CON diet ranged between 1.02 and 1.07, while that of ARG diet was 1.20. One room was constantly kept at thermoneutral (TN) conditions, while the birds in the other room were kept at TN conditions until D34 and subjected to cyclic HS from D35 onwards (∼34°C; 9:00 A.M.–6:00 P.M.). Blood, liver, Pectoralis major muscle, and cecal content were taken from 2 birds per pen (12 birds/group/room) for metabolomics and microbiota analysis. Growth performance data were also collected on a pen basis. Arginine supplementation failed to reduce the adverse effects of HS on growth performance. Supplemented birds showed increased levels of arginine and creatine in plasma, liver, and P. major and methionine in liver, and reduced levels of glutamine in plasma, liver, and P. major. HS altered bioenergetic processes (increased levels of AMP and reduced levels of fumarate, succinate, and UDP), protein metabolism (increased protein breakdown to supply the liver with amino acids for energy production), and promoted the accumulation of antioxidant and protective molecules (histidine-containing dipeptides, beta-alanine, and choline), especially in P. major. Arginine supplementation may have partially counterbalanced the effects of HS on energy homeostasis by increasing creatine levels and attenuating the increase in AMP levels, particularly in P. major. It also significantly reduced cecal observed diversity, while HS increased alpha diversity indices and affected beta diversity. Results of taxonomic analysis at the phylum and family level are also provided

    L'associazione della PI 3-chinasi ad un sito specifico del recettore per l'IL-1 media l'attivazione di NF-kB

    No full text
    Dottorato di ricerca in biologia cellulare e molecolare. 12. ciclo. A.a. 1998-99. Docente supervisore Albertino Ferri. Coordinatore Enrico GraziConsiglio Nazionale delle Ricerche - Biblioteca Centrale - P.le Aldo Moro, 7, Rome; Biblioteca Nazionale Centrale - P.za Cavalleggeri, 1, Florence / CNR - Consiglio Nazionale delle RichercheSIGLEITItal
    • …
    corecore