Background Dietary fat is important for energy provision and immune function of lactating sows and their progeny.However,knowledge on the impact of fat on mammary transcription of lipogenic genes,de novo fat synthesis...Background Dietary fat is important for energy provision and immune function of lactating sows and their progeny.However,knowledge on the impact of fat on mammary transcription of lipogenic genes,de novo fat synthesis,and milk fatty acid(FA)output is sparse in sows.This study aimed to evaluate impacts of dietary fat levels and FA composition on these traits in sows.Forty second-parity sows(Danish Landrace×Yorkshire)were assigned to 1 of 5 dietary treatments from d 108 of gestation until weaning(d 28 of lactation):low-fat control diet(3%added animal fat);or 1 of 4 high-fat diets with 8%added fat:coconut oil(CO),fish oil(FO),sunflower oil(SO),or 4%octanoic acid plus 4%FO(OFO).Three approaches were taken to estimate de novo milk fat synthesis from glucose and body fat.Results Daily intake of FA was lowest in low-fat sows within fat levels(P<0.01)and in OFO and FO sows within highfat diets(P<0.01).Daily milk outputs of fat,FA,energy,and FA-derived carbon reflected to a large extent the intake of those.On average,estimates for de novo fat synthesis were 82 or 194 g/d from glucose according to method 1 or 2 and 255 g de novo+mobilized FA/d according to method 3.The low-fat diet increased mammary FAS expression(P<0.05)and de novo fat synthesis(method 1;P=0.13)within fat levels.The OFO diet increased de novo fat synthesis(method 1;P<0.05)and numerically upregulated mammary FAS expression compared to the other high-fat diets.Across diets,a daily intake of 440 g digestible FA minimized milk fat originating from glucose and mobilized body fat.Conclusions Sows fed diets with low-fat or octanoic acid,through upregulating FAS expression,increased mammary de novo fat synthesis whereas the milk FA output remained low in sows fed the low-fat diet or high-fat OFO or FO diets,indicating that dietary FA intake,dietary fat level,and body fat mobilization in concert determine de novo fat synthesis,amount and profiles of FA in milk.展开更多
Objective The present study investigated the sodium/iodide symporter mRNA expression in mouse lactating mammary gland cells under different iodine levels and the effects of thyroid-stimulating hormone(TSH),estradiol(E...Objective The present study investigated the sodium/iodide symporter mRNA expression in mouse lactating mammary gland cells under different iodine levels and the effects of thyroid-stimulating hormone(TSH),estradiol(E2)and prolactin(PRL)on NIS mRNA expression in mouse lactating mammary gland cells.展开更多
Five female transgenic mice were produced by microinjection using a construct made up of a 7.3-kb-5′ flanking region and a 2.0-kb coding region of human a-lactalbumin, as well as a 227-bp 3′-flanking region from bov...Five female transgenic mice were produced by microinjection using a construct made up of a 7.3-kb-5′ flanking region and a 2.0-kb coding region of human a-lactalbumin, as well as a 227-bp 3′-flanking region from bovine growth hormone gene. A founder female ex-pressed human a-lactalbumin as much as 0.3 g per liter of its milk, approximately a 3-fold in-crease in the total a-lactalbumin concentration of the transgenic mouse milk. Compared with the normal mice, the expression profile of the ha-Lac transgene in the transgenics is different during the lactation, showing low level in the first 3 days and becoming increased from day 4, then gradually reaching and stabilizing at the highest level from day 13. In addition, the milk yielding volume in the transgenics tended to be higher than in normal mice, suggesting higher concen-trations of a-lactalbumin might boost more milk output.展开更多
基金Financially supported by the Danish Council for Independent Research,Technology and Production Sciences (Copenhagen K,Denmark)。
文摘Background Dietary fat is important for energy provision and immune function of lactating sows and their progeny.However,knowledge on the impact of fat on mammary transcription of lipogenic genes,de novo fat synthesis,and milk fatty acid(FA)output is sparse in sows.This study aimed to evaluate impacts of dietary fat levels and FA composition on these traits in sows.Forty second-parity sows(Danish Landrace×Yorkshire)were assigned to 1 of 5 dietary treatments from d 108 of gestation until weaning(d 28 of lactation):low-fat control diet(3%added animal fat);or 1 of 4 high-fat diets with 8%added fat:coconut oil(CO),fish oil(FO),sunflower oil(SO),or 4%octanoic acid plus 4%FO(OFO).Three approaches were taken to estimate de novo milk fat synthesis from glucose and body fat.Results Daily intake of FA was lowest in low-fat sows within fat levels(P<0.01)and in OFO and FO sows within highfat diets(P<0.01).Daily milk outputs of fat,FA,energy,and FA-derived carbon reflected to a large extent the intake of those.On average,estimates for de novo fat synthesis were 82 or 194 g/d from glucose according to method 1 or 2 and 255 g de novo+mobilized FA/d according to method 3.The low-fat diet increased mammary FAS expression(P<0.05)and de novo fat synthesis(method 1;P=0.13)within fat levels.The OFO diet increased de novo fat synthesis(method 1;P<0.05)and numerically upregulated mammary FAS expression compared to the other high-fat diets.Across diets,a daily intake of 440 g digestible FA minimized milk fat originating from glucose and mobilized body fat.Conclusions Sows fed diets with low-fat or octanoic acid,through upregulating FAS expression,increased mammary de novo fat synthesis whereas the milk FA output remained low in sows fed the low-fat diet or high-fat OFO or FO diets,indicating that dietary FA intake,dietary fat level,and body fat mobilization in concert determine de novo fat synthesis,amount and profiles of FA in milk.
文摘Objective The present study investigated the sodium/iodide symporter mRNA expression in mouse lactating mammary gland cells under different iodine levels and the effects of thyroid-stimulating hormone(TSH),estradiol(E2)and prolactin(PRL)on NIS mRNA expression in mouse lactating mammary gland cells.
文摘Five female transgenic mice were produced by microinjection using a construct made up of a 7.3-kb-5′ flanking region and a 2.0-kb coding region of human a-lactalbumin, as well as a 227-bp 3′-flanking region from bovine growth hormone gene. A founder female ex-pressed human a-lactalbumin as much as 0.3 g per liter of its milk, approximately a 3-fold in-crease in the total a-lactalbumin concentration of the transgenic mouse milk. Compared with the normal mice, the expression profile of the ha-Lac transgene in the transgenics is different during the lactation, showing low level in the first 3 days and becoming increased from day 4, then gradually reaching and stabilizing at the highest level from day 13. In addition, the milk yielding volume in the transgenics tended to be higher than in normal mice, suggesting higher concen-trations of a-lactalbumin might boost more milk output.
