Importance of mycotoxins in food and feed in India

Various food and feed samples including groundnut seed, maize, sorghum, soyabean cake, groundnut cake, cotton cake, poultry feed, buffalo milk, cow milk and milk powders were collected from farmers' fields, farmer's stores, oil millers storage, traders' storage, retail shops and supermarkets. More than 2000 samples were analysed by ELISA and most of the commodities, with the exception of sorghum seed, contained high levels of aflatoxin. Groundnut cake was one of the major cattle feed ingredients in the peri-urban area of Hyderabad (Andhra Pradesh, India) and >75% of the samples contained >100 µg/kg aflatoxin, leading to a high level of aflatoxin M1, in milk samples. Strategies to reduce aflatoxin levels (especially in groundnut) by management interventions at preharvest, harvest and storage, are discussed.

The economic viability and potential of a novel poultry agroforestry system

Investigating agroforestry systems that incorporate poultry is warranted in Northern Europe as they may offer benefits including: improved welfare and use of range; reduced feed costs; price premia on products; reduced payback periods for forests; and, greater returns on investment. Free-range egg production accounts for 27% of the United Kingdom egg market and demand for outdoor broilers is increasing. No research has been conducted recently on the economic viability of agroforestry systems with poultry. An economic model was constructed to: assess economic viability of a broiler agroforestry system; and, investigate the sensitivity of economic performance to key factors and interactions, and identify those which warrant attention in research and management. The system modelled is a commercial trial established in Southern England in 2002 where deciduous trees were planted and broilers reared in six- or nine-week periods. The model uses Monte Carlo simulation and financial performance analyses run for a 120-year period. An Internal Rate of Return (IRR) of 15.5% is predicted for the six-week system which remains viable under a 'worst case' scenario (IRR of 12.6%). Factors which affect financial performance most (decreasing in magnitude) are prices achieved for broilers, costs of brooding houses, chicks, arks, feed and timber prices. The main anticipated effects of biological interactions on financial performance (increased ranging on feed conversion and excess nutrient supply on tree health) were not supported by analysis. Further research is particularly warranted on the welfare benefits offered by the tree component and its relation to price premia.

Did pterosaurs feed by skimming? Physical modelling and anatomical evaluation of an unusual feeding method

Similarities between the anatomies of living organisms are often used to draw conclusions regarding the ecology and behaviour of extinct animals. Several pterosaur taxa are postulated to have been skim-feeders based largely on supposed convergences of their jaw anatomy with that of the modern skimming bird, Rynchops spp. Using physical and mathematical models of Rynchops bills and pterosaur jaws, we show that skimming is considerably more energetically costly than previously thought for Rynchops and that pterosaurs weighing more than one kilogram would not have been able to skim at all. Furthermore, anatomical comparisons between the highly specialised skull of Rynchops and those of postulated skimming pterosaurs suggest that even smaller forms were poorly adapted for skim-feeding. Our results refute the hypothesis that some pterosaurs commonly used skimming as a foraging method and illustrate the pitfalls involved in extrapolating from limited morphological convergence.

Did pterosaurs feed by skimming? Physical modelling and anatomical evaluation of an unusual feeding method

Similarities between the anatomies of living organisms are often used to draw conclusions regarding the ecology and behaviour of extinct animals. Several pterosaur taxa are postulated to have been skim-feeders based largely on supposed convergences of their jaw anatomy with that of the modern skimming bird, Rynchops spp. Using physical and mathematical models of Rynchops bills and pterosaur jaws, we show that skimming is considerably more energetically costly than previously thought for Rynchops and that pterosaurs weighing more than one kilogram would not have been able to skim at all. Furthermore, anatomical comparisons between the highly specialised skull of Rynchops and those of postulated skimming pterosaurs suggest that even smaller forms were poorly adapted for skim-feeding. Our results refute the hypothesis that some pterosaurs commonly used skimming as a foraging method and illustrate the pitfalls involved in extrapolating from limited morphological convergence.

Evaluation of the inclusion of a mixture of organic acids or lactulose into the feed of pigs experimentally challenged with Salmonella Typhimurium

A mixture of organic acids and lactulose for preventing or reducing colonization of the gut by Salmonella Typhimurium was evaluated in pigs. A total of 63 4-week-old commercial piglets were randomly distributed into three different experimental dietary groups: a plain diet without additives (PD) and the same diet supplemented with either 0.4% (w/v) formic acid and 0.4% lactic acid (w/v) (AC) or 1% (w/v) lactulose (LC). After 7 days of adaptation, two-thirds of the pigs (14 from each diet) were challenged with a 2-mL oral dose of 10(8) CFU/mL of Salmonella Typhimurium, leaving the remaining animals unchallenged (UC). After 4 and 10 days post-challenge, pigs were euthanized and the ileum and caecum content were aseptically sampled to (a) quantify lactic, formic, and short-chain fatty acids (SCFA), (b) quantify bacterial populations and Salmonella by fluorescence in situ hybridization and (c) qualitatively analyse bacterial populations through denaturing gradient gel electrophoresis (DGGE). Modification of fermentation products and counts of some of the bacterial groups analysed in the challenged pigs receiving the treatments AC and LC were minimal. Treatments only influenced the bacterial diversity after 10 days post-challenge, with AC generating a lower number of DGGE bands than UC(P < 0.05). Neither the inclusion of a mixture of 0.4% (w/v) formic and 0.4% (w/v) lactic acids nor of 1% (w/v) lactulose in the feed influenced numbers of Salmonella in the ileum and caecum of experimentally challenged pigs. (C) 2009 Elsevier B.V. All rights reserved.

Vitamin E supplementation, cereal feed type and consumer sensory perceptions of poultry meat quality

Lipid oxidation leads to meat spoilage and has been reported to cause adverse changes in the flavour and texture of poultry meat. Vitamin E has been found to be effective in delaying lipid oxidation. The aim of this study was to determine whether the vitamin E supplementation of chicken feed influences the consumers' perception of the quality of chicken meat under normal display and storage conditions. Untrained consumers (n 32) evaluated cooked breast meat from chickens (both corn fed and wheat fed) supplemented with 75 250 or 500 mg/kg vitamin E and after storage at 4&DEG; C for 4 and 7 d. Factorial analysis found an interaction between vitamin E treatment and storage day upon the perceived juiciness (P = 0.023) and tenderness (P = 0.041) of the chicken meat. Perceptions of quality relative to vitamin E level were more evident on day 4 than day 7. When the two cereal types were compared, the time-related subgroup effects were observed only in meat from corn-fed chickens supplemented with either 75 or 250 mg/kg, which was perceived to be juicier (P = 0.018) and more tender (P = 0.020) than that supplemented at the 500 mg/kg level. These results imply that the two lower concentrations of vitamin E have some advantages over 500 mg/kg, but for optimal consumer acceptance of corn-fed chicken meat, we suggest that 250 mg/kg vitamin E should be added to corn-fed poultry feed. There was no evidence to suggest any advantages in changing the current amount of vitamin E (75 mg/kg) used to rear wheat-fed birds.

The potential of probiotics as in-feed growth enhancers for swine

Probiotics have enjoyed a surge of popularity in recent years, with many novel applications being proposed. One of the foremost for the agricultural industry is their potential for livestock growth promotion, a subject of special interest since the 2006 EU-wide ban on sub therapeutic levels of in-feed antibiotic growth enhancers. Probiotics work through a number of differing mechanisms, most of which are not, as yet, fully understood. The probiotics interact with the host’s natural gut flora in a complex and varying array of mechanisms, but ultimately work to improve nutrient digestibility and gut health and to suppress the actions of pathogenic bacteria. In conclusion, probiotics can be a useful replacement for in-feed antibiotic growth enhancers. However, care should be taken due to the variability of the size of the effect and the inconsistency of the results in the published literature.

Effect of feed restriction and supplemental dietary fat on gut peptide and hypothalamic neuropeptide mRNA concentrations in growing wethers

The objectives of the present study were 1) to evaluate the effects of supplemental fat and ME intake on plasma concentrations of glucagon-like peptide-1 (GLP-1), cholecystokinin (CCK), glucose-dependent insulinotropic polypeptide, ghrelin, and oxyntomodulin; and 2) to determine the association of these peptides with DMI and the hypothalamic concentration of mRNA for the following neuropeptides: neuropeptide Y (NPY), agouti-related peptide (AgRP), and proopiomelanocortin (POMC). In a completely randomized block design with a 2 x 2 factorial arrangement of treatments, 32 pens with 2 wethers each were restricted-fed (2.45 Mcal/lamb per day) or offered diets ad libitum (n = 16) with or without 6% supplemental fat (n = 16) for a period of 30 d. Dry matter intake was measured daily. On d 8, 15, 22, and 29, BW was measured before feeding, and 6 h after feeding, blood samples were collected for plasma measurement of insulin, GLP-1, CCK, ghrelin, glucose-dependent insulinotropic polypeptide, oxyntomodulin, glucose, and NEFA concentrations. On d 29, blood was collected 30 min before feeding for the same hormone and metabolite analyses. At the end of the experiment, wethers were slaughtered and the hypothalami were collected to measure concentrations of NPY, AgRP, and POMC mRNA. Offering feed ad libitum (resulting in greater ME intake) increased plasma insulin and NEFA concentrations (P = 0.02 and 0.02, respectively) and decreased hypothalamic mRNA expression of NPY and AgRP (P = 0.07 and 0.02, respectively) compared with the restricted-fed wethers. There was a trend for the addition of dietary fat to decrease DMI (P = 0.12). Addition of dietary fat decreased insulin and glucose concentrations (P < 0.05 and 0.01, respectively) and tended to increase hypothalamic mRNA concentrations for NPY and AgRP (P = 0.07 and 0.11, respectively). Plasma GLP-1 and CCK concentrations increased in wethers offered feed ad libitum compared with restricted-fed wethers, but the response was greater when wethers were offered feed ad libitum and had supplemental fat in the diet (fat x intake interaction, P = 0.04). The prefeeding plasma ghrelin concentration was greater in restricted-fed wethers compared with those offered feed ad libitum, but the concentrations were similar 6 h after feeding (intake x time interaction, P < 0.01). Supplemental dietary fat did not affect (P = 0.22) plasma ghrelin concentration. We conclude that insulin, ghrelin, CCK, and GLP-1 may regulate DMI in sheep by regulating the hypothalamic gene expression of NPY, AgRP, and POMC.

Exchange rate pass-through to prices in macrodata: a comparative sensitivity analysis

This paper compares exchange rate pass-through to aggregate prices in the US, Germany and Japan across a number of dimensions. Building on the empirical approaches in the recent literature, our contribution is to perform a thorough sensitivity analysis of pass-through estimates. We find that the econometric method, data frequency and variable proxy employed matter for the precision of details, yet they often agree on some general trends. Thus, pass-through to import prices has declined in the 1990s relative to the 1980s, pass-through to export prices remains country-specific and pass-through to consumer prices is nowadays negligible in all three economies we considered.

Effects of beverage alcohol taxes and prices on drinking: a meta-analysis of 1003 estimates from 112 studies

Aims: We conducted a systematic review of studies examining relationships between measures of beverage alcohol tax or price levels and alcohol sales or self-reported drinking. A total of 112 studies of alcohol tax or price effects were found, containing 1003 estimates of the tax/price–consumption relationship. Design: Studies included analyses of alternative outcome measures, varying subgroups of the population, several statistical models, and using different units of analysis. Multiple estimates were coded from each study, along with numerous study characteristics. Using reported estimates, standard errors, t-ratios, sample sizes and other statistics, we calculated the partial correlation for the relationship between alcohol price or tax and sales or drinking measures for each major model or subgroup reported within each study. Random-effects models were used to combine studies for inverse variance weighted overall estimates of the magnitude and significance of the relationship between alcohol tax/price and drinking. Findings: Simple means of reported elasticities are -0.46 for beer, -0.69 for wine and -0.80 for spirits. Meta-analytical results document the highly significant relationships (P < 0.001) between alcohol tax or price measures and indices of sales or consumption of alcohol (aggregate-level r = -0.17 for beer, -0.30 for wine, -0.29 for spirits and -0.44 for total alcohol). Price/tax also affects heavy drinking significantly (mean reported elasticity = -0.28, individual-level r = -0.01, P < 0.01), but the magnitude of effect is smaller than effects on overall drinking. Conclusions: A large literature establishes that beverage alcohol prices and taxes are related inversely to drinking. Effects are large compared to other prevention policies and programs. Public policies that raise prices of alcohol are an effective means to reduce drinking.