The effect of 17β-estradiol on lactose in plasma and urine in dairy cows in late lactation. Issue 2 (23rd May 2019)

• Record Type: Journal Article
• Authors: Agenäs, Sigrid; Lundström, Idamaria; Holtenius, Kjell
• Is Part Of: Journal of dairy research. Volume 86:Issue 2(2019)
• Page Start: 188
• Page End: 192
• Publication Date: 2019-05-23
• Subjects: Blood:milk barrier, -- lactation, -- mammary tight junction, -- pregnancy; Dairying -- Periodicals; Dairying -- Research -- Periodicals; 636.214205
• DOI: 10.1017/S0022029919000281
• Languages: English
• ISSNs: 0022-0299

Abstract

Abstract: The aim of this study was to investigate the effect of 17β-estradiol on mammary tight junctions in cows in late lactation. The experiment included five non-pregnant cows around day 290 in lactation. The cows received injections of 17β-estradiol for six days. The effect of exogenous 17β-estradiol on milk yield, milk composition and lactose in plasma and lactose in urine was investigated before, during and after the treatment. Milk yield decreased after 17β-estradiol injections and lactose in plasma and urine increased, showing an effect on the integrity of the mammary tight junctions. However, there was a delay between hormone injections and the decrease in milk yield and opening of tight junctions, indicating that other factors are involved. A high correlation between lactose in urine and blood plasma was found. More than 30% of the total lactose production was lost in urine after 17β-estradiol treatment.