Research Note: Comparative effects of liquid and dry applications of a combination of lysolecithin, synthetic emulsifier, and monoglycerides on growth performance, nutrient digestibility, and litter moisture in broilers fed diets of differing energy density.

Supplementation of a combination of lysolecithin, a synthetic emulsifier, and monoglycerides (LEX) in liquid and dry form to broiler diets with different energy levels was investigated to determine their effect on performance, litter quality and subsequent occurrence of footpad lesions. One thousand two hundred and forty-eight-day-old Ross 308 broilers were assigned to 1 of 6 treatments for a 42-day study: a basal diet with a normal energy content (NE); NE + 300 g/t LEX in liquid form (LEL); NE + 500 g/t LEX in dry form (LED); a basal diet with low energy (LE, -90 kcal/kg starter, -100 kcal/kg grower, finisher), LE + 300 g/t LEL and a LE + 500 g/t LED. Each treatment consisted of 13 pens of 16 birds each. Diets were fed in 3 phases (starter d 0-10, grower d 11-21, finisher d 22-42). Feed intake and weight were measured on d 0, 10, 21, and 42. On d 42 a litter sample was collected from each pen and 2 birds per pen were assessed for footpad lesions and breast scald. Data were analyzed using JMP 16, with means separation achieved using Tukey's HSD; significance was assumed at P < 0.05. Results showed a higher (P < 0.05) cumulative bodyweight gain with LEX supplementation (NE CON = 2,718 g, NE+LED = 2,829, NE+LEL = 2,895, LE CON = 2,722, LE+LED = 2,787, LE+LEL = 2,893; P = 0.0027). An increased feed intake was observed for the LE diets, however cumulative FCR of LE+LED and LE+LEL remained equal to the NE control (1.657 NE CON, 1.657 LE+LED, 1.623 LE+LEL; P > 0.05), suggesting LEX enabled the birds to compensate for the energy gap. Litter dry matter was significantly improved with both LED and LEL supplementation compared to the control groups, and resulted in lower (P < 0.05) occurrence and severity of footpad lesions and breast scalds. Considering the income over feed cost (IOFC) of the NE treatment as the reference point for comparison, all other treatments improved profitability, with NE+LEL and LE+LEL achieving the greatest IOFC with 154.58 and 175.96 €/1,000 birds respectively. In conclusion, feeding broilers a combination of lysophospholipids, a synthetic emulsifier and monoglycerides resulted in improved bird performance. The use of the LEX also improved litter quality and footpad health, therefore improving animal welfare indicators such as breast scald and footpad measurements.

Plectranthus amboinicus and rosemary (Rosmarinus officinalis L.) essential oils effects on performance, antioxidant activity, intestinal health, immune response, and plasma biochemistry in broiler chickens.

This work aimed to assess the effects of Plectranthus amboinicus essential oil (PAE) and rosemary (Rosmarinus officinalis L.) essential oil (ROE) as feed additives on performance, antioxidant activity, intestinal microbiota, intestinal morphology, immune response, and plasma biochemistry using 320 unsexed 1-day-old Ross 308 broiler chickens. The chickens were assigned randomly into four treatments containing eight replicates with 10 chickens each. Treatment diets included a basal diet as a control group, 100 mg/kg PAE, 200 mg/kg PAE, and 100 mg/kg ROE. ROE affected the growth performance in the starter phase by improving (p = .01) the feed conversion ratio (FCR) compared with the control diet. Glutathione peroxidase (GPx) and superoxide dismutase (SOD) activity in the plasma were elevated (p < .0001) by both feed additives. Supplementation of additives could increase (p < .006) total antioxidant capacity (TAC). Furthermore, malondialdehyde (MDA) values in the breast (p < .0001) and thigh (p < .001) for all supplemented diets were less than the control group. The essential oils (EOs) reduced (p < .005) coliform counts in the ileum and increased (p = .029) lactic acid bacteria counts. In addition, villus height (VH) and crypt depth (CD) increased, whereas the density of goblet cells decreased in the small intestine when feed additives were included. Also, the antibody titers against sheep red blood cells (SRBC) and Newcastle disease virus (NDV) were increased (p < .0001) by EOs. Plasma total protein (p = .04) and globulin (p = .02) were increased, and cholesterol was reduced (p = .002) by supplemented diets. Our study revealed that PAE could effectively improve the antioxidant activity, intestinal microbiota population, intestinal morphology, immune response, and plasma biochemistry parameters in broiler chickens.

Accentuating the positive and eliminating the negative: Efficacy of TiO2 as digestibility index marker for poultry nutrition studies.

Inert digestibility index markers such as titanium dioxide are universally accepted to provide simple measurement of digestive tract retention and relative digestibility in poultry feeding trials. Their use underpins industry practice: specifically dosing regimens for adjunct enzymes added to animal feed. Among these, phytases, enzymes that degrade dietary phytate, inositol hexakisphosphate, represent a billion-dollar sector in an industry that raises ca. 70 billion chickens/annum. Unbeknown to the feed enzyme sector, is the growth in cell biology of use of titanium dioxide for enrichment of inositol phosphates from extracts of cells and tissues. The adoption of titanium dioxide in cell biology arises from its affinity under acid conditions for phosphates, suggesting that in feeding trial contexts that target phytate degradation this marker may not be as inert as assumed. We show that feed grade titanium dioxide enriches a mixed population of higher and lower inositol phosphates from acid solutions. Additionally, we compared the extractable inositol phosphates in gizzard and ileal digesta of 21day old male Ross 308 broilers fed three phytase doses (0, 500 and 6000 FTU/kg feed) and one inositol dose (2g/kg feed). This experiment was performed with or without titanium dioxide added as a digestibility index marker at a level of 0.5%, with all diets fed for 21 days. Analysis yielded no significant difference in effect of phytase inclusion in the presence or absence of titanium dioxide. Thus, despite the utility of titanium dioxide for recovery of inositol phosphates from biological samples, it seems that its use as an inert marker in digestibility trials is justified-as its inclusion in mash diets does not interfere with the recovery of inositol phosphates from digesta samples.

Phytase dose-dependent response of kidney inositol phosphate levels in poultry.

Phytases, enzymes that degrade phytate present in feedstuffs, are widely added to the diets of monogastric animals. Many studies have correlated phytase addition with improved animal productivity and a subset of these have sought to correlate animal performance with phytase-mediated generation of inositol phosphates in different parts of the gastro-intestinal tract or with release of inositol or of phosphate, the absorbable products of phytate degradation. Remarkably, the effect of dietary phytase on tissue inositol phosphates has not been studied. The objective of this study was to determine effect of phytase supplementation on liver and kidney myo-inositol and myo-inositol phosphates in broiler chickens. For this, methods were developed to measure inositol phosphates in chicken tissues. The study comprised wheat/soy-based diets containing one of three levels of phytase (0, 500 and 6,000 FTU/kg of modified E. coli 6-phytase). Diets were provided to broilers for 21 D and on day 21 digesta were collected from the gizzard and ileum. Liver and kidney tissue were harvested. Myo-inositol and inositol phosphates were measured in diet, digesta, liver and kidney. Gizzard and ileal content inositol was increased progressively, and total inositol phosphates reduced progressively, by phytase supplementation. The predominant higher inositol phosphates detected in tissues, D-and/or L-Ins(3,4,5,6)P4 and Ins(1,3,4,5,6)P5, differed from those (D-and/or L-Ins(1,2,3,4)P4, D-and/or L-Ins(1,2,5,6)P4, Ins(1,2,3,4,6)P5, D-and/or L-Ins(1,2,3,4,5)P5 and D-and/or L-Ins(1,2,4,5,6)P5) generated from phytate (InsP6) degradation by E. coli 6-phytase or endogenous feed phytase, suggesting tissue inositol phosphates are not the result of direct absorption. Kidney inositol phosphates were reduced progressively by phytase supplementation. These data suggest that tissue inositol phosphate concentrations can be influenced by dietary phytase inclusion rate and that such effects are tissue specific, though the consequences for physiology of such changes have yet to be elucidated.

Bioavailability of Methionine-Coated Zinc Nanoparticles as a Dietary Supplement Leads to Improved Performance and Bone Strength in Broiler Chicken Production.

Recently, nanotechnology has been widely adopted in many fields. The goal of this study was to evaluate the potential for amino acid coated nano minerals as a supplement in broiler feed. Zinc was selected as a model mineral for this test and supplementation of nano zinc, both coated and uncoated was compared with organic and inorganic commercial forms of zinc. A total of 48 pens (8 birds each) were assigned to one of the following dietary treatments: Control, methionine-Zinc chelate (M-Zn), nano zinc oxide (Nano-ZnO), and methionine coated nano zinc oxide (M-Nano-ZnO). All experimental diets were formulated with the same total zinc, methionine, protein, and energy content with just the zinc source as a variable. Bird weight, feed intake and feed conversion ratios were recorded weekly, with three birds culled (sacrificed) at day 21 and day 35 for sampling measures. Ileal digestibility of zinc was determined at day 21 and day 35 using titanium dioxide as an inert marker. Blood serum, liver and spleen samples were collected at day 21 and day 35 and analysed for zinc content via inductively coupled plasma mass spectrometry (ICP-MS). Tibia strength and morphometrics were measured from both legs of three birds per pen at day 21 and day 35. The study was conducted at Nottingham Trent University Poultry Unit, UK. The novel method of producing nano minerals coated with amino acids was successfully tested with zinc and material produced to test in the feeding study. Methionine coated nano zinc oxide supplementation significantly improved bird weight gain and the increased feed intake of broilers compared to an inorganic zinc form. Ileal digestibility was also improved with this methionine-nano zinc. Moreover, this supplementation improved the tibia strength of broilers at the age of 21 days, though this was not observed at day 35. Therefore, M-Nano-ZnO could be used to supplement broilers to improve both performance and digestibility with a limited positive impact on bone strength. The results of the current study suggest that the amino acid coating of nano minerals can improve the digestibility of minerals which may have further implications for the field of mineral nutrition in animal feeds.

Characterization of yellow root cassava and food products: investigation of cyanide and ß-carotene concentrations.

OBJECTIVE: Cyanide is a highly toxic compound, and the consumption of products containing cyanide is a significant public health concern. Conversely, ß-carotene possesses essential nutritional attributes for human health, therefore the characterisation and quantification of both compounds in food products is fundamental. Herein, cyanide and ß-carotene levels in two flours produced from the roots of two varieties of cassava (Manihot esculenta crantz), namely UMUCASS-38(TMS 01/1371) and NR-8082, and their associated food products were detected and quantified. RESULTS: The cyanide content of NR-8082 and UMUCASS-38 flours was determined at 18.01 ± 0.01 ppm and 17.02 ± 0.02 ppm (mean ± SD), respectively. These flours contained significantly higher (p < 0.05) than the residual cyanide levels determined in the cookies and cake produced therefrom with levels of 10.00 ± 0.00 ppm and 7.10 ± 0.14 ppm (mean ± SD), respectively. The levels of ß-carotene determined in both the cake and cookie samples varied significantly (p < 0.05). The highest levels of ß-carotene at 6.53 ± 0.02 µg/g (mean ± SD) were determined in raw roots of UMUCASS-38. While NR-8082 levels of ß-carotene were less than UMUCASS-38 at 1.12 ± 0.02 µg/g (mean ± SD). Processing the roots into flour reduced the ß-carotene content to 4.78 ± 0.01 µg/g and 0.76 ± 0.02 µg/g (mean ± SD) in UMUCASS-38 and NR-8082 flours, respectively. Cookies and cake produced from flour derived from the UMUCASS-38 variety had (mean ± SD) 2.15 ± 0.01 µg/g and 2.84 ± 0.04 µg/g of ß-carotene, respectively.

G-Protein coupled receptors: structure and function in drug discovery.

The G-protein coupled receptors (GPCRs) superfamily comprise similar proteins arranged into families or classes thus making it one of the largest in the mammalian genome. GPCRs take part in many vital physiological functions making them targets for numerous novel drugs. GPCRs share some distinctive features, such as the seven transmembrane domains, they also differ in the number of conserved residues in their transmembrane domain. Here we provide an introductory and accessible review detailing the computational advances in GPCR pharmacology and drug discovery. An overview is provided on family A-C GPCRs; their structural differences, GPCR signalling, allosteric binding and cooperativity. The dielectric constant (relative permittivity) of proteins is also discussed in the context of site-specific environmental effects.

Effect of feeding broilers diets differing in susceptible phytate content.

Measurements of total phytate phosphorus content of diets may be deceptive as they do not indicate substrate availability for phytase; it may be that measurements of phytate susceptible to phytase effects are a more accurate measure of phosphorus (P) availability to the bird. To verify this hypothesis, an experiment was conducted to compare diets formulated to contain either high or low susceptible phytate, supplemented with either 0 or 500 FTU/kg phytase. Susceptible phytate was determined by exposing the feed samples to conditions that mimicked the average pH of the proximal gastrointestinal tract (pH 4.5) and the optimum temperature for phytase activity (37 °C) and then measuring phytate dissolved. Ross 308 birds (n = 240) were fed one of 4 dietary treatments in a 2 × 2 factorial design; 2 diets with high (8.54 g/kg, 57.90% of total phytate) or low (5.77 g/kg, 46.33% of total phytate) susceptible phytate, containing 0 or 500 FTU/kg phytase. Diets were fed to broilers (12 replicate pens of 5 birds per pen) from d 0 to 28 post hatch. Birds fed diets high in susceptible phytate had greater phytate hydrolysis in the gizzard (P < 0.001), jejunum (P < 0.001) and ileum (P < 0.001) and resulting greater body weight gain (BWG) (P = 0.015) and lower FCR (P = 0.003) than birds fed the low susceptible phytate diets, irrespective of phytase presence. Birds fed the high susceptible diets also had greater P solubility in the gizzard and Ca and P solubility in the jejunum and ileum (P < 0.05) and resulting greater tibia and femur Ca and P (P < 0.05) content than those fed the low susceptible diets. All the susceptible phytate was fully degraded in the tract in the absence of added phytase, suggesting the assay used in this study was able to successfully estimate the amount of total dietary phytate that was susceptible to the effects of phytase when used at standard levels. No interactions were observed between susceptible phytate and phytase on phytate hydrolysis. Hydrolysis of phytate was greater (P < 0.05) in the gizzard of birds fed the diets supplemented with phytase, regardless of the concentration of susceptible phytate in the diet. Phytase supplementation resulted in improved BWG (P < 0.001) and FCR (P = 0.001), increased P solubility (P < 0.001) in the gizzard, Ca and P solubility (P < 0.001) in the jejunum and ileum and Ca and P concentration (P < 0.001) and strength (P < 0.001) in the tibia and femur. Pepsin activity was higher in birds fed the diets supplemented with phytase (P < 0.001) and was greater (P = 0.031) in birds fed the high susceptible phytate diets compared with the low susceptible phytate diets. Findings from this study suggest that there may be a measure more meaningful to animal nutritionists than measurements of total phytate.