Probiotics administration can improve host health. This study aims to determine the effects of probiotics （Lactobacillus casei Zhang and Lactobacillus plantarum P-8） administration on milk production, milk func- tio...Probiotics administration can improve host health. This study aims to determine the effects of probiotics （Lactobacillus casei Zhang and Lactobacillus plantarum P-8） administration on milk production, milk func- tional components, milk composition, and fecal microbiota of dairy cows. Variations in the fecal bacteria microbiota between treatments were assessed based on 16S rRNA profiles determined by PacBio single molecule real-time sequencing technology. The probiotics supplementation significantly increased the milk production and the contents of milk immunoglobulin C （IgG）, lactoferrin （LTF）, lysozyme （LYS） and lactoperoxidase （LP）, while the somatic cell counts （SCC） significantly decreased （P〈0.01）. However, no significant difference was found in the milk fat, protein and lactose contents （P 〉 0.05）. Although the probiotics supplementation did not change the fecal bacteria richness and diversity, significantly more rumen fermentative bacteria （ Bacteroides, Roseburia, Ruminococcus, CIostridium, Coprococcus and Dorea） and beneficial bacteria （Faecalibacterium prausnitzii） were found in the probiotics treatment group. Meanwhile, some opportunistic pathogens e.g. Bacillus cereus, Cronobacter sakazakii and Alkaliphilus oremlandii, were suppressed. Additionally, we found some correlations between the milk production, milk components and fecal bacteria. To sum up, our study demonstrated the beneficial effects of probiotics application in improving the quality and quantity of cow milk production.展开更多
Four Holstein dairy cows in the 7th month of late lactation were sampled, and self-control method was used. Daidzein was added to the concentrated feed at the dose of 10mg/kg during the treatment stage. Results showed...Four Holstein dairy cows in the 7th month of late lactation were sampled, and self-control method was used. Daidzein was added to the concentrated feed at the dose of 10mg/kg during the treatment stage. Results showed that daidzein lessened the declining tendency of milk yield in late lactation and increased the milk yield to some extents. Lactoprotein was evidently increased (P<0.01), while milkfat was not affected evidently. The level of T4 in serum was evidently increased (P<0.05); the levels of GH, PRL, E2 and TSH in serum were prone to rising while T3 was prone to decreasing . It was concluded that daidzein could indirectly affect milk yield and components of milk by regulating the levels of intrinsic hormones.展开更多
Background:The local supply of energy-yielding nutrients such as glucose seems to affect the synthesis of milk components in the mammary gland(MG).Thus,our study was conducted to investigate the effects of locally ava...Background:The local supply of energy-yielding nutrients such as glucose seems to affect the synthesis of milk components in the mammary gland(MG).Thus,our study was conducted to investigate the effects of locally available MG glucose supply(LMGS)on amino acid(AA)sensing and utilization in the MG of lactating dairy goats.Six dosages of glucose(0,20,40,60,80,and 100 g/d)were infused into the MG through the external pudendal artery to investigate the dose-dependent changes in mammary AA uptake and utilization(Exp.1)and the changes in mRNA and protein expression of the AMPK-mTOR pathway(Expt.2).Results:In Exp.1,total milk AA concentration was highest when goats were infused with 60 g/d glucose,but lower when goats were infused with 0 and 100 g/d glucose.Increasing LMGS quadratically changed the percentages ofαS2-casein andα-lactalbumin in milk protein,which increased with infusions from 0 to 60 g/d glucose and then decreased with infusions between 60 and 100 g/d glucose.The LMGS changed the AA availability and intramammary gland AA utilization,as reflected by the mammary AA flux indexes.In Exp.2,the mRNA expression of LALBA in the MG increased quadratically with increasing LMGS,with the highest expression at dose of 60 g/d glucose.A high glucose dosage(100 g/d)activated the general control nonderepressible 2 kinase,an intracellular sensor of AA status,resulting in a reduced total milk AA concentration.Conclusions:Our new findings suggest that the lactating MG in dairy goats may be affected by LMGS through regulation of the AA sensory pathway,AA utilization and protein synthesis,all being driven by the AMPK-mTOR pathway.展开更多
This experiment was conducted to investigate the effects of infusing milk precursors into the external pudic artery on rumen fermentation in lactating dairy cows. Eight multiparous Holstein cows were randomly assigned...This experiment was conducted to investigate the effects of infusing milk precursors into the external pudic artery on rumen fermentation in lactating dairy cows. Eight multiparous Holstein cows were randomly assigned to Group A(experimental group) and Group B(control group) with 4 cows each. A2×4 complex factor crossover design was used. Cows in Group A were fed corn straw as the only roughage, and cows in Group B were fed mixed roughage. The experiment was divided into two periods.In the first period, cows in Group A, received treatments: 1) a basal infusate as a control(CSC); 2) a milk fat precursor infusion including C16:0, C18:0, C18:1 c9, C18:2 c6, C18:3 n3, acetic acid(CSF); 3) a milk protein precursor infusion including 16 amino acids(CSA); 4) the mixed infusion of milk fat and protein precursors(CSFA). And meanwhile, cows in Group B were infused the basal infusate as a control group. In the second period, the cows in both Groups A and B were crossed over, which cows in Group A were named as Group B and the cows originally in Group B were in Group A. The experimental results showed that cows in experimental group had higher ruminal pH compared with the control, and ruminal pH in CSC, CSF, CSA were significantly higher than those in their respective control group(P < 0.05). The concentration of ammonia nitrogen(NH_3-N) was significantly higher in CSA and CSFA compared with Group B(P < 0.05). We also observed that the infusion of mixed amino acids significantly increased the bacterial protein(BCP) content in rumen(P < 0.05) and influenced the rumen acetic acid concentration as well as the acetic to propionic ratio(P < 0.05). Milk fat precursors infusion significantly affected butyric acid concentration(P < 0.05). In addition, the content of lipopolysaccharide(LPS) in CSA was significantly higher than that in the control group(P < 0.05). It is concluded that the milk precursors infused into external pudic artery caused feedback effects on ruminal fermentation under the corn straw roughage conditions. The milk protein precursor increased the ruminal pH, the contents of BCP and acetic acid, which adjust rumen fermentation and improve milk performance.展开更多
基金supported by the China Agriculture Research System(CARS-37)the Major Project of the Inner Mongolia Autonomous region
文摘Probiotics administration can improve host health. This study aims to determine the effects of probiotics （Lactobacillus casei Zhang and Lactobacillus plantarum P-8） administration on milk production, milk func- tional components, milk composition, and fecal microbiota of dairy cows. Variations in the fecal bacteria microbiota between treatments were assessed based on 16S rRNA profiles determined by PacBio single molecule real-time sequencing technology. The probiotics supplementation significantly increased the milk production and the contents of milk immunoglobulin C （IgG）, lactoferrin （LTF）, lysozyme （LYS） and lactoperoxidase （LP）, while the somatic cell counts （SCC） significantly decreased （P〈0.01）. However, no significant difference was found in the milk fat, protein and lactose contents （P 〉 0.05）. Although the probiotics supplementation did not change the fecal bacteria richness and diversity, significantly more rumen fermentative bacteria （ Bacteroides, Roseburia, Ruminococcus, CIostridium, Coprococcus and Dorea） and beneficial bacteria （Faecalibacterium prausnitzii） were found in the probiotics treatment group. Meanwhile, some opportunistic pathogens e.g. Bacillus cereus, Cronobacter sakazakii and Alkaliphilus oremlandii, were suppressed. Additionally, we found some correlations between the milk production, milk components and fecal bacteria. To sum up, our study demonstrated the beneficial effects of probiotics application in improving the quality and quantity of cow milk production.
基金Elitist Innovation Fund of Henan Province (12100030)
文摘Four Holstein dairy cows in the 7th month of late lactation were sampled, and self-control method was used. Daidzein was added to the concentrated feed at the dose of 10mg/kg during the treatment stage. Results showed that daidzein lessened the declining tendency of milk yield in late lactation and increased the milk yield to some extents. Lactoprotein was evidently increased (P<0.01), while milkfat was not affected evidently. The level of T4 in serum was evidently increased (P<0.05); the levels of GH, PRL, E2 and TSH in serum were prone to rising while T3 was prone to decreasing . It was concluded that daidzein could indirectly affect milk yield and components of milk by regulating the levels of intrinsic hormones.
基金This work was supported by the grants from the Natural Science Foundation of China(31802083)the China Agriculture(Dairy)Research System(CARS-36).
文摘Background:The local supply of energy-yielding nutrients such as glucose seems to affect the synthesis of milk components in the mammary gland(MG).Thus,our study was conducted to investigate the effects of locally available MG glucose supply(LMGS)on amino acid(AA)sensing and utilization in the MG of lactating dairy goats.Six dosages of glucose(0,20,40,60,80,and 100 g/d)were infused into the MG through the external pudendal artery to investigate the dose-dependent changes in mammary AA uptake and utilization(Exp.1)and the changes in mRNA and protein expression of the AMPK-mTOR pathway(Expt.2).Results:In Exp.1,total milk AA concentration was highest when goats were infused with 60 g/d glucose,but lower when goats were infused with 0 and 100 g/d glucose.Increasing LMGS quadratically changed the percentages ofαS2-casein andα-lactalbumin in milk protein,which increased with infusions from 0 to 60 g/d glucose and then decreased with infusions between 60 and 100 g/d glucose.The LMGS changed the AA availability and intramammary gland AA utilization,as reflected by the mammary AA flux indexes.In Exp.2,the mRNA expression of LALBA in the MG increased quadratically with increasing LMGS,with the highest expression at dose of 60 g/d glucose.A high glucose dosage(100 g/d)activated the general control nonderepressible 2 kinase,an intracellular sensor of AA status,resulting in a reduced total milk AA concentration.Conclusions:Our new findings suggest that the lactating MG in dairy goats may be affected by LMGS through regulation of the AA sensory pathway,AA utilization and protein synthesis,all being driven by the AMPK-mTOR pathway.
文摘This experiment was conducted to investigate the effects of infusing milk precursors into the external pudic artery on rumen fermentation in lactating dairy cows. Eight multiparous Holstein cows were randomly assigned to Group A(experimental group) and Group B(control group) with 4 cows each. A2×4 complex factor crossover design was used. Cows in Group A were fed corn straw as the only roughage, and cows in Group B were fed mixed roughage. The experiment was divided into two periods.In the first period, cows in Group A, received treatments: 1) a basal infusate as a control(CSC); 2) a milk fat precursor infusion including C16:0, C18:0, C18:1 c9, C18:2 c6, C18:3 n3, acetic acid(CSF); 3) a milk protein precursor infusion including 16 amino acids(CSA); 4) the mixed infusion of milk fat and protein precursors(CSFA). And meanwhile, cows in Group B were infused the basal infusate as a control group. In the second period, the cows in both Groups A and B were crossed over, which cows in Group A were named as Group B and the cows originally in Group B were in Group A. The experimental results showed that cows in experimental group had higher ruminal pH compared with the control, and ruminal pH in CSC, CSF, CSA were significantly higher than those in their respective control group(P < 0.05). The concentration of ammonia nitrogen(NH_3-N) was significantly higher in CSA and CSFA compared with Group B(P < 0.05). We also observed that the infusion of mixed amino acids significantly increased the bacterial protein(BCP) content in rumen(P < 0.05) and influenced the rumen acetic acid concentration as well as the acetic to propionic ratio(P < 0.05). Milk fat precursors infusion significantly affected butyric acid concentration(P < 0.05). In addition, the content of lipopolysaccharide(LPS) in CSA was significantly higher than that in the control group(P < 0.05). It is concluded that the milk precursors infused into external pudic artery caused feedback effects on ruminal fermentation under the corn straw roughage conditions. The milk protein precursor increased the ruminal pH, the contents of BCP and acetic acid, which adjust rumen fermentation and improve milk performance.
