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Peter Kappel Theil

Continuous lactation effects on mammary remodeling during late gestation and lactation in dairy goats

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Continuous lactation effects on mammary remodeling during late gestation and lactation in dairy goats. / Safayi, Sina; Theil, Peter Kappel; Hou, Lei; Engbæk, Marie; Nørgaard, Jan Værum; Sejrsen, Kristen; Nielsen, Mette Benedicte Olaf.

In: Journal of Dairy Science, Vol. 93, No. 1, 2010, p. 203-217.

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review

Harvard

Safayi, S, Theil, PK, Hou, L, Engbæk, M, Nørgaard, JV, Sejrsen, K & Nielsen, MBO 2010, 'Continuous lactation effects on mammary remodeling during late gestation and lactation in dairy goats', Journal of Dairy Science, vol. 93, no. 1, pp. 203-217. https://doi.org/10.3168/jds.2009-2507

APA

Safayi, S., Theil, P. K., Hou, L., Engbæk, M., Nørgaard, J. V., Sejrsen, K., & Nielsen, M. B. O. (2010). Continuous lactation effects on mammary remodeling during late gestation and lactation in dairy goats. Journal of Dairy Science, 93(1), 203-217. https://doi.org/10.3168/jds.2009-2507

CBE

MLA

Vancouver

Author

Safayi, Sina ; Theil, Peter Kappel ; Hou, Lei ; Engbæk, Marie ; Nørgaard, Jan Værum ; Sejrsen, Kristen ; Nielsen, Mette Benedicte Olaf. / Continuous lactation effects on mammary remodeling during late gestation and lactation in dairy goats. In: Journal of Dairy Science. 2010 ; Vol. 93, No. 1. pp. 203-217.

Bibtex

@article{cd9cc62005b411df8775000ea68e967b,
title = "Continuous lactation effects on mammary remodeling during late gestation and lactation in dairy goats",
abstract = "The present study aimed to 1) elucidate whether continuous milking during late gestation in dairy goats negatively affects mammary remodeling and hence milk production in the subsequent lactation, and 2) identify the regulatory factors responsible for changes in cell turnover and angiogenesis in the continuously lactating mammary gland. Nine multiparous dairy goats were used. One udder half was dried off approximately 9 wk prepartum (normal lactation; NL), and the other udder half of the same goat was milked continuously (continuous lactation; CL) until parturition or until the half-udder milk yields had dropped to below 50 g/d. Mammary biopsies were obtained from each udder half just before the NL gland was dried off (before dry period), within the first 2 wk after drying-off (early dry period, samples available only for NL glands), in the mid dry period, within the last 2 wk before parturition (late dry period), and at d 1 (the day of parturition), 3, 10, 60, and 180 of lactation. Mammary morphology was characterized in biopsies by quantitative histology, and cell turnover was determined by immunohistochemistry (terminal deoxynucleotidyl transferase dUTP nick end labeling and Ki-67). Transcription of genes encoding factors involved in mammary epithelial cell (MEC) turnover and vascular function was quantified by quantitative reverse transcription PCR. Results demonstrated that omitting the dry period was possible in goats but was not as easy as claimed before. Renewal of MEC was suppressed in CL glands, which resulted in a smaller MEC population in the subsequent lactation. At the time of parturition (and throughout lactation), the mammary glands subjected to CL had smaller alveoli, more fully differentiated MEC, and a substantially larger capillary fraction compared with NL glands. The continuously lactating gland thus resembled a normally lactating gland in an advanced stage of lactation. None of the studied genomic factors could account for these treatment differences. The described characteristics in CL glands compared with NL glands indicated a gland maintained in lactation for a longer period.",
keywords = "Continued milking, Cell turnover, Angiogenesis, Dry off",
author = "Sina Safayi and Theil, {Peter Kappel} and Lei Hou and Marie Engb{\ae}k and N{\o}rgaard, {Jan V{\ae}rum} and Kristen Sejrsen and Nielsen, {Mette Benedicte Olaf}",
year = "2010",
doi = "10.3168/jds.2009-2507",
language = "English",
volume = "93",
pages = "203--217",
journal = "Journal of Dairy Science",
issn = "0022-0302",
publisher = "Elsevier Inc.",
number = "1",

}

RIS

TY - JOUR

T1 - Continuous lactation effects on mammary remodeling during late gestation and lactation in dairy goats

AU - Safayi, Sina

AU - Theil, Peter Kappel

AU - Hou, Lei

AU - Engbæk, Marie

AU - Nørgaard, Jan Værum

AU - Sejrsen, Kristen

AU - Nielsen, Mette Benedicte Olaf

PY - 2010

Y1 - 2010

N2 - The present study aimed to 1) elucidate whether continuous milking during late gestation in dairy goats negatively affects mammary remodeling and hence milk production in the subsequent lactation, and 2) identify the regulatory factors responsible for changes in cell turnover and angiogenesis in the continuously lactating mammary gland. Nine multiparous dairy goats were used. One udder half was dried off approximately 9 wk prepartum (normal lactation; NL), and the other udder half of the same goat was milked continuously (continuous lactation; CL) until parturition or until the half-udder milk yields had dropped to below 50 g/d. Mammary biopsies were obtained from each udder half just before the NL gland was dried off (before dry period), within the first 2 wk after drying-off (early dry period, samples available only for NL glands), in the mid dry period, within the last 2 wk before parturition (late dry period), and at d 1 (the day of parturition), 3, 10, 60, and 180 of lactation. Mammary morphology was characterized in biopsies by quantitative histology, and cell turnover was determined by immunohistochemistry (terminal deoxynucleotidyl transferase dUTP nick end labeling and Ki-67). Transcription of genes encoding factors involved in mammary epithelial cell (MEC) turnover and vascular function was quantified by quantitative reverse transcription PCR. Results demonstrated that omitting the dry period was possible in goats but was not as easy as claimed before. Renewal of MEC was suppressed in CL glands, which resulted in a smaller MEC population in the subsequent lactation. At the time of parturition (and throughout lactation), the mammary glands subjected to CL had smaller alveoli, more fully differentiated MEC, and a substantially larger capillary fraction compared with NL glands. The continuously lactating gland thus resembled a normally lactating gland in an advanced stage of lactation. None of the studied genomic factors could account for these treatment differences. The described characteristics in CL glands compared with NL glands indicated a gland maintained in lactation for a longer period.

AB - The present study aimed to 1) elucidate whether continuous milking during late gestation in dairy goats negatively affects mammary remodeling and hence milk production in the subsequent lactation, and 2) identify the regulatory factors responsible for changes in cell turnover and angiogenesis in the continuously lactating mammary gland. Nine multiparous dairy goats were used. One udder half was dried off approximately 9 wk prepartum (normal lactation; NL), and the other udder half of the same goat was milked continuously (continuous lactation; CL) until parturition or until the half-udder milk yields had dropped to below 50 g/d. Mammary biopsies were obtained from each udder half just before the NL gland was dried off (before dry period), within the first 2 wk after drying-off (early dry period, samples available only for NL glands), in the mid dry period, within the last 2 wk before parturition (late dry period), and at d 1 (the day of parturition), 3, 10, 60, and 180 of lactation. Mammary morphology was characterized in biopsies by quantitative histology, and cell turnover was determined by immunohistochemistry (terminal deoxynucleotidyl transferase dUTP nick end labeling and Ki-67). Transcription of genes encoding factors involved in mammary epithelial cell (MEC) turnover and vascular function was quantified by quantitative reverse transcription PCR. Results demonstrated that omitting the dry period was possible in goats but was not as easy as claimed before. Renewal of MEC was suppressed in CL glands, which resulted in a smaller MEC population in the subsequent lactation. At the time of parturition (and throughout lactation), the mammary glands subjected to CL had smaller alveoli, more fully differentiated MEC, and a substantially larger capillary fraction compared with NL glands. The continuously lactating gland thus resembled a normally lactating gland in an advanced stage of lactation. None of the studied genomic factors could account for these treatment differences. The described characteristics in CL glands compared with NL glands indicated a gland maintained in lactation for a longer period.

KW - Continued milking

KW - Cell turnover

KW - Angiogenesis

KW - Dry off

U2 - 10.3168/jds.2009-2507

DO - 10.3168/jds.2009-2507

M3 - Journal article

C2 - 20059919

VL - 93

SP - 203

EP - 217

JO - Journal of Dairy Science

JF - Journal of Dairy Science

SN - 0022-0302

IS - 1

ER -