Consumer acceptance of dairy products with a saturated fatty acid-reduced, monounsaturated fatty acid-enriched content

Agriculture-based reformulation initiatives, including oleic acid-rich lipid supplementation of the dairy cow diet, provide a novel means for reducing intake of saturated fatty acids (SFA) at a population level. In a blinded manner, this study evaluated the consumer acceptance of SFA-reduced, monounsaturated fatty acid-enriched (modified) milk, Cheddar cheese, and butter when compared with control and commercially available comparative samples. The effect of providing nutritional information about the modified cheese was also evaluated. Consumers (n = 115) rated samples for overall liking (appearance, flavor, and texture) using 9-point hedonic scales. Although no significant differences were found between the milk samples, the modified cheese was liked significantly less than a regular-fat commercial alternative for overall liking and liking of specific modalities and had a lower liking of texture score compared with the control cheese. The provision of health information significantly increased the overall liking of the modified cheese compared with tasting the same sample in a blinded manner. Significant differences were evident between the butter samples for overall liking and modalities of liking; all of the samples were significantly more liked than the commercial butter and sunflower oil spread. In conclusion, this study illustrated that consumer acceptance of SFA-reduced, monounsaturated fatty acid-enriched dairy products was dependent on product type. Future research should consider how optimization of the textural properties of fatty acid-modified (and fat-reduced) cheese might enhance consumer acceptance of this product

Effects of delayed feeding, sodium butyrate and glutamine on intestinal permeability in newly-hatched broiler chickens

The aim of the current study was to investigate the effects of delayed feeding, and supplementation with sodium butyrate or glutamine in drinking water, on intestinal permeability (IP) in young broiler chickens. Newly-hatched male chickens (Ross 308) were allocated to four groups comprising Control, 24 h delayed fed (DF), DF supplemented with sodium butyrate (0.1%) in the drinking water and DF supplemented with glutamine (1%) in the drinking water. On days 2, 4 and 7, twelve birds per group were randomly selected, weighed and orally gavaged with fluorescein isothiocyanate dextran (FITC-d) at 2.2 mg / ml / chicken. Serum FITC-d concentration was analysed by spectrophotometry while serum diamine oxidase and D-lactic acid concentrations were analysed by microplate reader. FITC-d concentrations in the Control and DF groups were not statistically different on any day, suggesting that delayed feeding did not affect IP. Additionally, sodium butyrate increased IP compared to DF and Control on day 2 only (p

Challenges in enriching milk fat with polyunsaturated fatty acids

Milk fatty acid composition is determined by several factors including diet. The milk fatty acid profile of dairy cows is low in polyunsaturated fatty acids, especially those of the n-3 series. Efforts to change and influence fatty acid profile with longer chain polyunsaturated fatty acids have proven challenging. Several barriers prevent easy transfer of dietary polyunsaturated fatty acids to milk fat including rumen biohydrogenation and fatty acid esterification. The potential for cellular uptake and differences in fatty acid incorporation into milk fat might also have an effect, though this has received less research effort. Given physiological impediments to enriching milk fat with polyunsaturated fatty acids, manipulating the genome of the cow might provide a greater increase than diet alone, but this too may be challenged by the physiology of the cow

Comparison of methods used to predict the in vivo digestibility of feeds in ruminants

Digestibility is a very useful index of the energy content of ruminant feeds, but cheaper and quicker laboratory methods are required as an alternative to the ultimate measure of in vivo digestibility using animals. These methods involve either prediction of digestibility from chemical composition or in vitro and in situ simulation of the digestion process. This review presents a range of chemical and in vitro techniques for predicting digestibility, together with an assessment of their advantages and limitations, particularly the degree to which they account for the sources of variation in in vivo digestibility in ruminants. In situ digestion of feed samples in the actual rumen environment is probably the most accurate of the non in vivo procedures, but is not suitable for routine application. Thein vitro gas production technique offers no advantages in prediction of total tract digestibility, but is useful for screening cereal grains for rate of starch hydrolysis in the rumen. The preferred procedure for routine laboratory prediction of digestibility is the pepsin-cellulase technique, provided amylase is included or high temperature digestion is used for samples high in starch content. Prediction of digestibility from chemical composition is not recommended. The optical technique of near infrared reflectance spectroscopy can be calibrated against any of the methods outlined in this review, and is unsurpassed in terms of speed and repeatability. Direct NIR prediction of in vivo digestibility is also possible, but is limited by the lack of adequate numbers of feed samples with known in vivo values. Future work should be aimed at filling this gap and also improving the accuracy of laboratory methods for predicting the digestibility of low quality feed

Comparison of methods used to predict the in vivo digestibility of feeds in ruminants

Digestibility is a very useful index of the energy content of ruminant feeds, but cheaper and quicker laboratory methods are required as an alternative to the ultimate measure of in vivo digestibility using animals. These methods involve either prediction of digestibility from chemical composition or in vitro and in situ simulation of the digestion process. This review presents a range of chemical and in vitro techniques for predicting digestibility, together with an assessment of their advantages and limitations, particularly the degree to which they account for the sources of variation in in vivo digestibility in ruminants. In situ digestion of feed samples in the actual rumen environment is probably the most accurate of the non in vivo procedures, but is not suitable for routine application. Thein vitro gas production technique offers no advantages in prediction of total tract digestibility, but is useful for screening cereal grains for rate of starch hydrolysis in the rumen. The preferred procedure for routine laboratory prediction of digestibility is the pepsin-cellulase technique, provided amylase is included or high temperature digestion is used for samples high in starch content. Prediction of digestibility from chemical composition is not recommended. The optical technique of near infrared reflectance spectroscopy can be calibrated against any of the methods outlined in this review, and is unsurpassed in terms of speed and repeatability. Direct NIR prediction of in vivo digestibility is also possible, but is limited by the lack of adequate numbers of feed samples with known in vivo values. Future work should be aimed at filling this gap and also improving the accuracy of laboratory methods for predicting the digestibility of low quality feed

Yield, Composition and in vitro Digestibility of Russell Lupin

Six harvests were made (at 3-weekly intervals) from spring regrowth of Russell lupin (Lupinus polyphyllus x Lupinus arboreus ) to evaluate changes in yield and nutritive value with plant maturity. Dry matter (DM) yield and neutral detergent fibre (NDF) concentration increased from 40 to 160 g/plant and 24 to 46%, respectively, while nitrogen concentration, in vitro cellulase DM and organic matter digestibility decreased from 4.5-2.4%, 77-56% and 81-55%, respectively, as the lupins matured from late vegetative to hard pod stage. Peak digestible DM (DDM) yields of Russell lupins, at about 90 g/plant, occurred at full bloom and dry pod, The first peak DDM yield had less DDM from dead matter and a greater proportion of DDM from components with \u3e80 % DM digestibility, It was concluded that Russell lupin produces highly digestible DM with high N concentration and maintain these qualities over a long period

Mucin gene mRNA levels in broilers challenged with Eimeria and/or Clostridium Perfringens

The effects of Eimeria (EM) and Clostridium perfringens (CP) challenges on the mRNA levels of genes involved in mucin (Muc) synthesis (Muc2, Muc5ac, Muc13, and trefoil family factor-2 [TFF2]), inflammation (tumor necrosis factor alpha [TNF-α] and interleukin-18 [IL-18]), and metabolic processes (cluster of differentiation [CD]36) in the jejunum of broilers were investigated. Two parallel experiments involving 1) EM challenge and 2) EM and CP challenges were conducted. The first experiment was a 2 × 2 study with 12 birds per treatment (N  =  48) involving fishmeal substitution (25%) in the diet (FM) and EM challenge. The treatments were: Control (FM−, EM−), Fishmeal (FM+, EM−), EM challenge (FM−, EM+), and fishmeal substitution and EM challenge (FM+, EM+). The second experiment was a 2 × 2 × 2 experiment with six birds per treatment (N  =  48) involving fishmeal (FM−, FM+), Eimeria (EM−, EM+), and C. perfringens (CP−, CP+). In both arms of the study, male broilers were given a starter diet for the whole period of 16 days, except those assigned to FM+, where 25% of the starter ration was replaced with fishmeal from days 8 to 14. EM inoculation was performed on day 9 and CP inoculation on days 14 and 15. The EM challenge birds were euthanatized for sampling on day 13; postmortem examination and sampling for the Eimeria plus C. perfringens challenge arm of the study were on day 16. In the Eimeria challenge arm of the study, fishmeal supplementation significantly suppressed the mRNA levels of TNF-α, TFF2, and IL-18 pre-CP inoculation but simultaneously increased the levels of Muc13 and CD36 mRNAs. Birds challenged with Eimeria exhibited increased mRNA levels of Muc13, Muc5ac, TNF-α, and IL-18. In the Eimeria and C. perfringens challenge arm, birds exposed to EM challenge exhibited significantly lower mRNA levels of Muc2 and CD36. The mRNA levels of CD36 were also significantly suppressed by CP challenge. Our results showed that the transcription of mucin synthesis genes in the jejunum of broilers is modulated by fishmeal inclusion in the diet. Furthermore, we show for the first time suppression of CD36 mRNA levels in the intestine of broilers challenged with Eimeria or C. perfringens.Soressa M. Kitessa, Gregory S. Nattrass, Rebecca E. A. Forder, Hayley A. McGrice, Shu-Biao Wu, and Robert J. Hughe