Background： Indigestible markers are commonly utilized in digestion studies, but the complete disappearance or maximum appearance of a marker in feces can be affected by diet composition, feed intake, or an animal＇s...Background： Indigestible markers are commonly utilized in digestion studies, but the complete disappearance or maximum appearance of a marker in feces can be affected by diet composition, feed intake, or an animal＇s BW.The objectives of this study were to determine the impact of previous（Phase 1, P1） and current-（Phase 2, P2）diet composition on marker disappearance（Cr） and appearance（Ti） in pigs fed 3 diets differing in NDF content.Results： When pigs were maintained on the 25.1, 72.5, and 125.0 g/kg NDF diets, it took 5.1, 4.1, and 2.5 d, respectively,for Cr levels to decrease below the limit of quantitation; or 4.6, 3.7, or 2.8 d, respectively, for Ti to be maximized. These effects were not, however, independent of the previous diet as indicated by the interaction between P1 and P2 diets on fecal marker concentrations（P 〈 0.01）. When dietary NDF increased from P1 to P2, it took less time for fecal Cr to decrease or fecal Ti to be maximized（an average of 2.5 d）, than if NDF decreased from P1 to P2 where it took longer for fecal Cr to decrease or fecal Ti to be maximized（an average of 3.4 d）.Conclusions： Because of the wide range in excretion times reported in the literature and improved laboratory methods for elemental detection, the data suggests that caution must be taken in considering dietary fiber concentrations of the past and currently fed diets so that no previous dietary marker addition remains in the digestive tract or feces such that a smal amount of maker is present to confound subsequent experimental results, and that marker concentration have stabilized when these samples are col ected.展开更多
Background: Maize oil is abundantly used in foods and feeds and is highly susceptible to oxidation. Consequently,commercially available antioxidants should be evaluated for effectiveness against lipid oxidation in swi...Background: Maize oil is abundantly used in foods and feeds and is highly susceptible to oxidation. Consequently,commercially available antioxidants should be evaluated for effectiveness against lipid oxidation in swine diets. Our study was conducted to evaluate growth performance of nursery pigs fed oxidized maize oil and to determine effects of using antioxidants on oxidative status in a 2 × 2 factorial design. Two hundred eight weaned pigs were blocked by initial BW into 13 blocks, resulting in 4 pigs per pen and 13 pens per treatment. Dietary treatments included 6% unoxidized or oxidized maize oil, and 0 or 60 mg/kg of tert-butylhydroquinone(TBHQ), which was added after lipid oxidation. Data for growth performance were collected from 5 time periods of a two-phase feeding program(Phase 1 = d 0 to 12 and Phase 2 = d 13 to 34). Serum and liver samples were collected from one pig per pen, which had initial BW closest to average BW to determine oxidative status on d 34.Results: Oxidized maize oil was heated for 12 h at 185 °C with 12 L/min of air, yielding a peroxide value(PV) of 5.98 m Eq O2/kg and TBARS of 0.11 mg MDA eq/g. Addition of TBHQ to diets containing oxidized maize oil decreased PV by 37% and increased the oil stability index by 69%. Final BW, ADG, ADFI, and G:F of pigs were not different among the four dietary treatments. However, pigs fed oxidized maize oil tended(P < 0.08) to increase hepatosomatic index by 5% compared with those fed unoxidized oil, and this was not affected by adding TBHQ.The serum vitamin E concentration of pigs fed oxidized maize oil was less(P < 0.03) than pigs fed unoxidized oil,but this reduction was not reversed by adding TBHQ. Finally, the serum and liver selenium concentration were not different among the treatments.Conclusions: The addition of TBHQ did not affect growth performance and vitamin E status in pigs fed moderately oxidized maize oil, but TBHQ reduced lipid oxidation, enhanced the oil stability, and appeared to reduce oxidative stress.展开更多
Background: The benefits of using the oxidized oils from rendering and recycling as an economic source of lipids and energy in animal feed always coexist with the concerns that diverse degradation products in these ox...Background: The benefits of using the oxidized oils from rendering and recycling as an economic source of lipids and energy in animal feed always coexist with the concerns that diverse degradation products in these oxidized oils can negatively affect animal health and performance. Therefore, the quality markers that predict growth performance could be useful when feeding oxidized oils to non-ruminants. However, the correlations between growth performance and chemical profiles of oxidized oils have not been well examined. In this study, six thermally oxidized soybean oils(OSOs) with a wide range of quality measures were prepared under different processing temperatures and processing durations, including 45 °C-336 h;67.5 °C-168 h;90 °C-84 h;135 °C-42 h;180 °C-21 h;and225 °C-10.5 h. Broilers and nursery pigs were randomly assigned to diets containing either unheated control soybean oil or one of six OSOs. Animal performance was determined by measuring body weight gain, feed intake,and gain to feed ratio. The chemical profiles of OSOs were first evaluated by common indicative tests, including peroxide value, thiobarbituric acid reactive substances, p-anisidine value, free fatty acids, oxidized fatty acids,unsaponifiable matter, insoluble impurities, and moisture, and then analyzed by the liquid chromatography-mass spectrometry-based chemometric analysis.Results: Among common quality indicators, p-anisidine value(An V), which reflects the level of carbonyl compounds,had the greatest inverse correlation with the growth performance of both broilers and pigs, followed by free fatty acids and oxidized fatty acids. Among the 17 aldehydes identified in OSOs, C9-C11 alkenals, especially 2-decenal and 2-undecenal, had stronger inverse correlations(r <-0.8) with animal performance compared to C5-C8 saturated alkanals,suggesting that chain length and unsaturation level affect the toxicity of aldehydes.Conclusions: As the major lipid oxidation products contributing to the An V, individual C9-C11 unsaturated aldehydes in heavily-oxidized oils could function as effective prediction markers of growth and feed intake in feeding non-ruminants.展开更多
In livestock diets, energy is one of the most expensive nutritional components of feed formulation. Because lipids are a concentrated energy source, inclusion of lipids are known to affect growth rate and feed efficie...In livestock diets, energy is one of the most expensive nutritional components of feed formulation. Because lipids are a concentrated energy source, inclusion of lipids are known to affect growth rate and feed efficiency, but are also known to affect diet palatability, feed dustiness, and pellet quality. In reviewing the literature, the majority of research studies conducted on the subject of lipids have focused mainly on the effects of feeding presumably high quality lipids on growth performance, digestion, and metabolism in young animals. There is, however, the wide array of composition and quality differences among lipid sources available to the animal industry making it essential to understand differences in lipid composition and quality factors affecting their digestion and metabolism more fully. In addition there is often confusion in lipid nomenclature, measuring lipid content and composition, and evaluating quality factors necessary to understand the true feeding value to animals. Lastly, advances in understanding lipid digestion, post-absorption metabolism, and physiological processes（e.g., cell division and differentiation, immune function and inflammation）; and in metabolic oxidative stress in the animal and lipid peroxidation, necessitates a more compressive assessment of factors affecting the value of lipid supplementation to livestock diets. The following review provides insight into lipid classification, digestion and absorption, lipid peroxidation indices, lipid quality and nutritional value, and antioxidants in growing pigs.展开更多
基金the National Laboratory for Agriculture and the Environment (Ames, Iowa) for laboratory assistance. Appreciation is also expressed to H. J. Monegue and W. Patton (University of Kentucky, Lexington) for assistance in the care of pigs and to D. Higginbotham (University of Kentucky, Lexington) for help in diet preparation and to Akey Inc. (Lewisburg, OH) and DSM Nutritional Products Inc. (Parsippany, N J) for ingredients used in the diets. Mention of a trade name, proprietary product, or specific equipment does not constitute a guarantee or warranty by the USDA, Iowa State University, or the University of Kentucky and does not imply approval to the exclusion of other products that may be suitable. The USDA is an equal opportunity provider and employer.
文摘Background： Indigestible markers are commonly utilized in digestion studies, but the complete disappearance or maximum appearance of a marker in feces can be affected by diet composition, feed intake, or an animal＇s BW.The objectives of this study were to determine the impact of previous（Phase 1, P1） and current-（Phase 2, P2）diet composition on marker disappearance（Cr） and appearance（Ti） in pigs fed 3 diets differing in NDF content.Results： When pigs were maintained on the 25.1, 72.5, and 125.0 g/kg NDF diets, it took 5.1, 4.1, and 2.5 d, respectively,for Cr levels to decrease below the limit of quantitation; or 4.6, 3.7, or 2.8 d, respectively, for Ti to be maximized. These effects were not, however, independent of the previous diet as indicated by the interaction between P1 and P2 diets on fecal marker concentrations（P 〈 0.01）. When dietary NDF increased from P1 to P2, it took less time for fecal Cr to decrease or fecal Ti to be maximized（an average of 2.5 d）, than if NDF decreased from P1 to P2 where it took longer for fecal Cr to decrease or fecal Ti to be maximized（an average of 3.4 d）.Conclusions： Because of the wide range in excretion times reported in the literature and improved laboratory methods for elemental detection, the data suggests that caution must be taken in considering dietary fiber concentrations of the past and currently fed diets so that no previous dietary marker addition remains in the digestive tract or feces such that a smal amount of maker is present to confound subsequent experimental results, and that marker concentration have stabilized when these samples are col ected.
基金Funding for this research was provided by Kemin Industries,Des Moines,IA,USA
文摘Background: Maize oil is abundantly used in foods and feeds and is highly susceptible to oxidation. Consequently,commercially available antioxidants should be evaluated for effectiveness against lipid oxidation in swine diets. Our study was conducted to evaluate growth performance of nursery pigs fed oxidized maize oil and to determine effects of using antioxidants on oxidative status in a 2 × 2 factorial design. Two hundred eight weaned pigs were blocked by initial BW into 13 blocks, resulting in 4 pigs per pen and 13 pens per treatment. Dietary treatments included 6% unoxidized or oxidized maize oil, and 0 or 60 mg/kg of tert-butylhydroquinone(TBHQ), which was added after lipid oxidation. Data for growth performance were collected from 5 time periods of a two-phase feeding program(Phase 1 = d 0 to 12 and Phase 2 = d 13 to 34). Serum and liver samples were collected from one pig per pen, which had initial BW closest to average BW to determine oxidative status on d 34.Results: Oxidized maize oil was heated for 12 h at 185 °C with 12 L/min of air, yielding a peroxide value(PV) of 5.98 m Eq O2/kg and TBARS of 0.11 mg MDA eq/g. Addition of TBHQ to diets containing oxidized maize oil decreased PV by 37% and increased the oil stability index by 69%. Final BW, ADG, ADFI, and G:F of pigs were not different among the four dietary treatments. However, pigs fed oxidized maize oil tended(P < 0.08) to increase hepatosomatic index by 5% compared with those fed unoxidized oil, and this was not affected by adding TBHQ.The serum vitamin E concentration of pigs fed oxidized maize oil was less(P < 0.03) than pigs fed unoxidized oil,but this reduction was not reversed by adding TBHQ. Finally, the serum and liver selenium concentration were not different among the treatments.Conclusions: The addition of TBHQ did not affect growth performance and vitamin E status in pigs fed moderately oxidized maize oil, but TBHQ reduced lipid oxidation, enhanced the oil stability, and appeared to reduce oxidative stress.
基金partially supported by the Agricultural Experiment Station project MIN-18-125 (C. C.) from the United States Department of Agriculture(USDA)。
文摘Background: The benefits of using the oxidized oils from rendering and recycling as an economic source of lipids and energy in animal feed always coexist with the concerns that diverse degradation products in these oxidized oils can negatively affect animal health and performance. Therefore, the quality markers that predict growth performance could be useful when feeding oxidized oils to non-ruminants. However, the correlations between growth performance and chemical profiles of oxidized oils have not been well examined. In this study, six thermally oxidized soybean oils(OSOs) with a wide range of quality measures were prepared under different processing temperatures and processing durations, including 45 °C-336 h;67.5 °C-168 h;90 °C-84 h;135 °C-42 h;180 °C-21 h;and225 °C-10.5 h. Broilers and nursery pigs were randomly assigned to diets containing either unheated control soybean oil or one of six OSOs. Animal performance was determined by measuring body weight gain, feed intake,and gain to feed ratio. The chemical profiles of OSOs were first evaluated by common indicative tests, including peroxide value, thiobarbituric acid reactive substances, p-anisidine value, free fatty acids, oxidized fatty acids,unsaponifiable matter, insoluble impurities, and moisture, and then analyzed by the liquid chromatography-mass spectrometry-based chemometric analysis.Results: Among common quality indicators, p-anisidine value(An V), which reflects the level of carbonyl compounds,had the greatest inverse correlation with the growth performance of both broilers and pigs, followed by free fatty acids and oxidized fatty acids. Among the 17 aldehydes identified in OSOs, C9-C11 alkenals, especially 2-decenal and 2-undecenal, had stronger inverse correlations(r <-0.8) with animal performance compared to C5-C8 saturated alkanals,suggesting that chain length and unsaturation level affect the toxicity of aldehydes.Conclusions: As the major lipid oxidation products contributing to the An V, individual C9-C11 unsaturated aldehydes in heavily-oxidized oils could function as effective prediction markers of growth and feed intake in feeding non-ruminants.
文摘In livestock diets, energy is one of the most expensive nutritional components of feed formulation. Because lipids are a concentrated energy source, inclusion of lipids are known to affect growth rate and feed efficiency, but are also known to affect diet palatability, feed dustiness, and pellet quality. In reviewing the literature, the majority of research studies conducted on the subject of lipids have focused mainly on the effects of feeding presumably high quality lipids on growth performance, digestion, and metabolism in young animals. There is, however, the wide array of composition and quality differences among lipid sources available to the animal industry making it essential to understand differences in lipid composition and quality factors affecting their digestion and metabolism more fully. In addition there is often confusion in lipid nomenclature, measuring lipid content and composition, and evaluating quality factors necessary to understand the true feeding value to animals. Lastly, advances in understanding lipid digestion, post-absorption metabolism, and physiological processes（e.g., cell division and differentiation, immune function and inflammation）; and in metabolic oxidative stress in the animal and lipid peroxidation, necessitates a more compressive assessment of factors affecting the value of lipid supplementation to livestock diets. The following review provides insight into lipid classification, digestion and absorption, lipid peroxidation indices, lipid quality and nutritional value, and antioxidants in growing pigs.
