To investigate the relationship between feeding level during gestation and voluntary feed intake, feeding behavior, and plasma metabolite levels during lactation, 18 crossbred, primiparous sows were assigned to two dietary treatments. From d 60 of gestation until farrowing, sows were fed either a standard level of feed (SL; 1.85 kg/d) or were allowed ad libitum (AL) access to feed. During a 28-...

Prolactin, glucocorticoids, and insulin are commonly used to induce milk protein synthesis in bovine mammary cell cultures. In addition, administration of GH increases milk yield in dairy cows, likely via the mammalian target of rapamycin (mTOR) pathway and IGF-I synthesis. As such, the hypothesis of this study was that mRNA abundance of hormone receptors, mammalian target of mTOR pathway-relat...

To test the hypothesis that under restricted and surfeit protein intake the mammary gland undergoes adaptive regulation, changes in mammary tissue mRNA abundance of cationic amino acid (AA) transporter (CAT)-1, CAT-2B, alanine/serine/cysteine/threonine transporter 1 (ASCT1), and broad specificity transporter for neutral and cationic AA (ATB(0,+)), and CAT-1 protein abundance were investigated a...

This study was conducted to compare three models: two random regression models with and without considering heterogeneity in the residual variances and a lactation model (LM) for evaluating the genetic ability of Holstein cows in Korea. Two datasets were prepared for this study. To apply the test-day random regression model, 94,390 test-day records were prepared from 15,263 cows. The second dat...

Trials were conducted to evaluate effects of a fermentation extract of Aspergillus oryzae (AO) on milk production and composition, diet digestibility, and rectal temperature changes in lactating dairy cows. Treatments were incorporated as a top dressing at the morning feeding and consisted of control (90 g/d of ground sorghum) or AO (3 g of culture + 87 g of ground sorghum daily). Twenty-four m...

protection of the mammary gland against mastitis-causing pathogens is mediated by many factors in thegland and blood circulation. the professional phagocytic cells of bovine udder, polymorphonuclearneutrophils (pmn) and macrophages, comprise the first line of defense against invading mastitis pathogens.most researchers now accept that the pmn is a key factor in the cows’ defense against intrama...

Sows that were either fat or lean at farrowing (340 or 280 g of body fat/kg BW, respectively) were offered either a low-protein (LP; 7.9% CP and 15.5 MJ DE/kg as fed) or a high-protein (HP; 19.0% CP and 15.6 MJ DE/kg as fed) diet on an ad libitum basis throughout a 4-wk lactation to test the hypothesis that the amount of milk and its composition are responsive to the supply of endogenous (body ...

OBJECTIVE The aim of the current study was to describe the relationship between milk yield and lactation number, stage, length and milking frequency in Korean Holstein dairy cows using an automatic milking system (AMS). METHODS The original data set consisted of observations from April to October 2016 of 780 Holstein cows, with a total of 10,751 milkings. Each time a cow was milked by an AMS ...

The effect of feeding sows a starch diet or a diet with a high level of nonstarch polysaccharides (NSP) during gestation, lactation, or both gestation and lactation during the first three parities on reproductive performance, body weight, and backfat was studied. Four-hundred and forty-four postpuberal gilts were allotted to a 2 x 2 x 2 factorial experiment. Treatments were diet composition dur...

The aims of this study were, first, to evaluate the effects of climatic variables on daily feed intake of lactating sows and, second, to establish whether the response of sows to variation in temperature on feed intake during lactation was heritable. A total of 82,614 records for daily feed intake during lactation were available for 848 sows with 3,369 litters farrowing from January 2000 to Dec...