Chromium yeast(CY)supplementation has the potential to alleviate the negative effects of heat stress in dairy cows,but the mechanism remains elusive.We aimed to identify the metabolic mechanisms whereby CY supplementa...Chromium yeast(CY)supplementation has the potential to alleviate the negative effects of heat stress in dairy cows,but the mechanism remains elusive.We aimed to identify the metabolic mechanisms whereby CY supplementation alleviates the negative effects of heat stress in mid-lactation dairy cows.Twelve Holstein dairy cows with similar milk yield(24.6±1.5 kg/d),parity(2 or 3)and days in milk(125±8 d)were fed the same basal diet containing 0.09 mg of Cr/kg DM.They were allocated randomly to 2 groups:a control group(CON,without CY supplementation)and a CY group(CY,administered 0.36 mg Cr/kg DM).The experiment was performed over 8 weeks during a hot summer,in which the mean temperature-humidity index was 79.0±3.13(>72),indicating that the dairy cows were exposed to heat stress.Chromium yeast supplementation reduced rectal temperature(P=0.032),and increased the lactation performance by increasing the yield of milk(+2.6 kg/d),protein,lactose and total solid,and protein and lactose percentages in the milk of the heat-stressed dairy cows(P<0.05).Supplementation with CY increased the serum glucose and thyroxine concentrations,but reduced the urea nitrogen,in-sulin,and triiodothyronine concentrations on d 56(P<0.05).Furthermore,plasma metabolomic analysis was performed using liquid chromatography tandem-mass spectrometry,which identified 385 metab-olites in the two groups.Subsequently,16 significantly different metabolites in the plasma,were significantly higher in the CY group(variable importance for the projection>1.0,P<0.05),and found to be involved in 6 Kyoto Encyclopedia of Genes and Genomes pathways,including those involved in nicotinate and nicotinamide metabolism.Specifically,plasma concentration of nicotinamide was higher after CY supplementation,which might also contribute to the reduction of rectal temperature,the regulation of glucose homeostasis,and an improvement in the lactation performance of heat-stressed dairy cows.In conclusion,CY supplementation reduces rectal temperature,influences metabolism by reducing serum insulin concentration and increasing serum glucose and plasma nicotinamide concen-trations,and finally increases lactation performance of heat-stressed dairy cows.展开更多
[ Objective] To study the effects of yeast chromium combined with probiotics on laying performance, intestinal microflora and digestive enzyme activities of laying hens. [ Method] A total of 432 healthy 40-week-old Ro...[ Objective] To study the effects of yeast chromium combined with probiotics on laying performance, intestinal microflora and digestive enzyme activities of laying hens. [ Method] A total of 432 healthy 40-week-old Roman brown laying hens were randomly divided into nine groups. Laying hens in control group were fed with basal diet, laying hens in test groups were fed with basal diet combining with different levels of yeast chromium （0,400,600 μg/kg） or probiotics （0,400,800 mg/kg）. [ Result] Yeast chromium, probiotics or yeast chromium combined with probiotics adding into feeds could significantly increased the laying rate （ P 〈 0.05 ） and significantly reduced feed-egg rate （ P 〈 0.05 ）. Joint use of yeast chromium and probiotics had significant interaction effects on laying rate and feed conversion rate（P 〈 0. 05）. Adding of yeast chromium combined with probiotics in diets could significantly increased the amount of Lactobacillus and Bifidobacterium （P 〈0.05 ） in ileum and cecum of laying hens, and significantly reduced the amount of Escherichia coli and Salmonella （P 〈0.05 ） , in addition, the activity of total protease, lipase and amylase in duodenal contents were significantly increased （ P 〈 0.05 ）. Joint use of yeast chromium and probioties had sig- nificant interaction effects on the activity of total protease, lipase and amylase in laying hens duodenal contents （ P 〈 0.05 ）. [ Conclusion ] Joint adding of 600μg/kg yeast chromium and 800 mg/kg probiotics in diets in summer had best effects on laying performance, intestinal microflora and digestive enzyme activities of laying hens.展开更多
Yeasts and organic minerals are used in diets to improve health, productive performance and some carcass characteristics of ruminants and non-ruminants. Thirty-two lambs（Pelibuey×Katahdin; BW=（30.55±1.67）...Yeasts and organic minerals are used in diets to improve health, productive performance and some carcass characteristics of ruminants and non-ruminants. Thirty-two lambs（Pelibuey×Katahdin; BW=（30.55±1.67） kg; n=8） were used in a 56-d feeding experiment to study the effects of different levels of live yeast（Saccharomyces cerevisiae; yeast）, selenium（Se） and chromium（Cr） mixed（Se-Cr）, and a mixture of yeast-Se-Cr on growth performance and carcass traits. Animals were stratified by body weight（BW） and randomly assigned to one of four treatments： 1） control group（0.0 g kg–1 yeast）; 2） yeast（1.50 g kg–1 dry matter intake（DMI） d–1）; 3） Se-Cr premix（1.5 mg kg–1 DMI d–1 for each mineral）; and 4） yeast-Se-Cr mixture. There were no treatment effects on final BW; whereas lambs fed Se-Cr or yeast-Se-Cr had higher（P〈0.05） DMI than animals supplemented with only yeast. Average daily gain（ADG）, gain：feed ratio, chop area, dorsal fat and carcass yield were similar（P〉0.05） among treatment groups. In conclusion, supplementation with yeast, Se-Cr mixed or yeast-Se-Cr did not improve ADG, final BW, back fat content and carcass yield of growing of Pelibuey×Katahdin lambs. Supplementation with Se-Cr and yeast-Se-Cr increased DMI, and approximately 250 g ADG animal–1 d–1 was produced with no negative effects on growth and health of the animals.展开更多
基金supported by the National Key Research and Development Program of China(2022YFD1300505,2022YFD1301101)the earmarked fund for China Agriculture Research System(CARS-37)the Agricultural Science and Technology Innovation Program(cxgc-ias-07).
文摘Chromium yeast(CY)supplementation has the potential to alleviate the negative effects of heat stress in dairy cows,but the mechanism remains elusive.We aimed to identify the metabolic mechanisms whereby CY supplementation alleviates the negative effects of heat stress in mid-lactation dairy cows.Twelve Holstein dairy cows with similar milk yield(24.6±1.5 kg/d),parity(2 or 3)and days in milk(125±8 d)were fed the same basal diet containing 0.09 mg of Cr/kg DM.They were allocated randomly to 2 groups:a control group(CON,without CY supplementation)and a CY group(CY,administered 0.36 mg Cr/kg DM).The experiment was performed over 8 weeks during a hot summer,in which the mean temperature-humidity index was 79.0±3.13(>72),indicating that the dairy cows were exposed to heat stress.Chromium yeast supplementation reduced rectal temperature(P=0.032),and increased the lactation performance by increasing the yield of milk(+2.6 kg/d),protein,lactose and total solid,and protein and lactose percentages in the milk of the heat-stressed dairy cows(P<0.05).Supplementation with CY increased the serum glucose and thyroxine concentrations,but reduced the urea nitrogen,in-sulin,and triiodothyronine concentrations on d 56(P<0.05).Furthermore,plasma metabolomic analysis was performed using liquid chromatography tandem-mass spectrometry,which identified 385 metab-olites in the two groups.Subsequently,16 significantly different metabolites in the plasma,were significantly higher in the CY group(variable importance for the projection>1.0,P<0.05),and found to be involved in 6 Kyoto Encyclopedia of Genes and Genomes pathways,including those involved in nicotinate and nicotinamide metabolism.Specifically,plasma concentration of nicotinamide was higher after CY supplementation,which might also contribute to the reduction of rectal temperature,the regulation of glucose homeostasis,and an improvement in the lactation performance of heat-stressed dairy cows.In conclusion,CY supplementation reduces rectal temperature,influences metabolism by reducing serum insulin concentration and increasing serum glucose and plasma nicotinamide concen-trations,and finally increases lactation performance of heat-stressed dairy cows.
基金Supported by Beijing Agricultural Vocational College Project(XY-BS-12-03)Beijing Agricultural Science and Technology Project(20120108)Beijing Agricultural Vocational College Technology R&D and Demonstration Fund(XY-YF-13-18)
文摘[ Objective] To study the effects of yeast chromium combined with probiotics on laying performance, intestinal microflora and digestive enzyme activities of laying hens. [ Method] A total of 432 healthy 40-week-old Roman brown laying hens were randomly divided into nine groups. Laying hens in control group were fed with basal diet, laying hens in test groups were fed with basal diet combining with different levels of yeast chromium （0,400,600 μg/kg） or probiotics （0,400,800 mg/kg）. [ Result] Yeast chromium, probiotics or yeast chromium combined with probiotics adding into feeds could significantly increased the laying rate （ P 〈 0.05 ） and significantly reduced feed-egg rate （ P 〈 0.05 ）. Joint use of yeast chromium and probiotics had significant interaction effects on laying rate and feed conversion rate（P 〈 0. 05）. Adding of yeast chromium combined with probiotics in diets could significantly increased the amount of Lactobacillus and Bifidobacterium （P 〈0.05 ） in ileum and cecum of laying hens, and significantly reduced the amount of Escherichia coli and Salmonella （P 〈0.05 ） , in addition, the activity of total protease, lipase and amylase in duodenal contents were significantly increased （ P 〈 0.05 ）. Joint use of yeast chromium and probioties had sig- nificant interaction effects on the activity of total protease, lipase and amylase in laying hens duodenal contents （ P 〈 0.05 ）. [ Conclusion ] Joint adding of 600μg/kg yeast chromium and 800 mg/kg probiotics in diets in summer had best effects on laying performance, intestinal microflora and digestive enzyme activities of laying hens.
基金Dr. Adelfo Vite Aranda (Biotecap S A de C V, Tepatitlán, Jalisco, Mexico) for supplying ingredients and financial support used to this research
文摘Yeasts and organic minerals are used in diets to improve health, productive performance and some carcass characteristics of ruminants and non-ruminants. Thirty-two lambs（Pelibuey×Katahdin; BW=（30.55±1.67） kg; n=8） were used in a 56-d feeding experiment to study the effects of different levels of live yeast（Saccharomyces cerevisiae; yeast）, selenium（Se） and chromium（Cr） mixed（Se-Cr）, and a mixture of yeast-Se-Cr on growth performance and carcass traits. Animals were stratified by body weight（BW） and randomly assigned to one of four treatments： 1） control group（0.0 g kg–1 yeast）; 2） yeast（1.50 g kg–1 dry matter intake（DMI） d–1）; 3） Se-Cr premix（1.5 mg kg–1 DMI d–1 for each mineral）; and 4） yeast-Se-Cr mixture. There were no treatment effects on final BW; whereas lambs fed Se-Cr or yeast-Se-Cr had higher（P〈0.05） DMI than animals supplemented with only yeast. Average daily gain（ADG）, gain：feed ratio, chop area, dorsal fat and carcass yield were similar（P〉0.05） among treatment groups. In conclusion, supplementation with yeast, Se-Cr mixed or yeast-Se-Cr did not improve ADG, final BW, back fat content and carcass yield of growing of Pelibuey×Katahdin lambs. Supplementation with Se-Cr and yeast-Se-Cr increased DMI, and approximately 250 g ADG animal–1 d–1 was produced with no negative effects on growth and health of the animals.
