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פותח על ידי קלירמאש פתרונות בע"מ -
Subclinical, chronic intramammary infection lowers steroid concentrations and gene expression in bovine preovulatory follicles
Year:
2011
Source of publication :
Domestic Animal Endocrinology
Authors :
מועלם, עוזי
;
.
Volume :
40
Co-Authors:
Lavon, Y., Department of Animal Science, Faculty of Agriculture, Food and Environment, Hebrew University, Rehovot, Israel
Leitner, G., Mastitis Laboratory, Veterinary Institute, Bet Dagan, Israel
Klipper, E., Department of Animal Science, Faculty of Agriculture, Food and Environment, Hebrew University, Rehovot, Israel
Moallem, U., Institute of Animal Science, Agricultural Research Organization, Bet Dagan, Israel
Meidan, R., Department of Animal Science, Faculty of Agriculture, Food and Environment, Hebrew University, Rehovot, Israel
Wolfenson, D., Department of Animal Science, Faculty of Agriculture, Food and Environment, Hebrew University, Rehovot, Israel
Facilitators :
From page:
98
To page:
109
(
Total pages:
12
)
Abstract:
Chronic, subclinical intramammary infection depresses fertility. We previously found that 30% of subclinical mastitic cows exhibit delayed ovulation, low circulating estradiol levels, and delayed luteinizing hormone surge. We examined the function of preovulatory follicles of cows experiencing subclinical mastitis or a past event of acute clinical mastitis. Cows were diagnosed for mastitis by somatic cell count and bacteriological examination. All clinical infections were caused by Escherichia coli, and most subclinical infections were caused by Streptococcus dysgalactiae and coagulase-negative staphylococci. On day 6 of the cycle, cows received PGF2α; 42 h later, follicular fluids and granulosa cells or theca cells were aspirated from preovulatory follicles in vivo or following slaughter, respectively. Overall, follicular estradiol and androstenedione concentrations in the subclinical group (n = 28) were 40% lower (P < 0.05) than those in uninfected cows (n = 24) and lower than in past clinical mastitic cows (n = 9). Distribution analysis revealed a clear divergence among subclinical cows: one-third (9/28) exhibited low follicular estradiol; the other two-thirds had normal levels similar to all uninfected (P < 0.01) and most clinical cows (P < 0.08) that had normal follicular estradiol levels. Subclinical normal-estradiol cows had twofold higher (P < 0.05) circulating estradiol concentrations and sevenfold and fourfold higher (P < 0.05) follicular androstenedione levels and estradiol-to-progesterone ratio, respectively, than subclinical low-estradiol cows. Follicular progesterone level was not affected. Reduced expression (P < 0.05) of LHCGR in theca and granulosa cells, CYP11A1 (mRNA and protein) and CYP17A1 in theca cells, and CYP19A1 in granulosa cells may have contributed to the lower follicular steroid production in the subclinical low-estradiol subgroup. StAR and HSD3B1 in theca cells and FSHR in granulosa cells were not affected. Mastitis did not alter follicular growth dynamics, and no carryover effect of past clinical mastitis on follicular function was detected. These data indicate that a considerable proportion (one-third) of subclinical mastitic cows have abnormal follicular steroidogenesis, which can explain the reproductive failure associated with this disease. © 2011 Elsevier Inc.
Note:
Related Files :
Animal
Animals
biosynthesis
cattle
Female
gene expression
Genetics
metabolism
Microbiology
Steroids
עוד תגיות
תוכן קשור
More details
DOI :
10.1016/j.domaniend.2010.09.004
Article number:
Affiliations:
Database:
סקופוס
Publication Type:
מאמר
;
.
Language:
אנגלית
Editors' remarks:
ID:
18701
Last updated date:
02/03/2022 17:27
Creation date:
16/04/2018 23:23
You may also be interested in
Scientific Publication
Subclinical, chronic intramammary infection lowers steroid concentrations and gene expression in bovine preovulatory follicles
40
Lavon, Y., Department of Animal Science, Faculty of Agriculture, Food and Environment, Hebrew University, Rehovot, Israel
Leitner, G., Mastitis Laboratory, Veterinary Institute, Bet Dagan, Israel
Klipper, E., Department of Animal Science, Faculty of Agriculture, Food and Environment, Hebrew University, Rehovot, Israel
Moallem, U., Institute of Animal Science, Agricultural Research Organization, Bet Dagan, Israel
Meidan, R., Department of Animal Science, Faculty of Agriculture, Food and Environment, Hebrew University, Rehovot, Israel
Wolfenson, D., Department of Animal Science, Faculty of Agriculture, Food and Environment, Hebrew University, Rehovot, Israel
Subclinical, chronic intramammary infection lowers steroid concentrations and gene expression in bovine preovulatory follicles
Chronic, subclinical intramammary infection depresses fertility. We previously found that 30% of subclinical mastitic cows exhibit delayed ovulation, low circulating estradiol levels, and delayed luteinizing hormone surge. We examined the function of preovulatory follicles of cows experiencing subclinical mastitis or a past event of acute clinical mastitis. Cows were diagnosed for mastitis by somatic cell count and bacteriological examination. All clinical infections were caused by Escherichia coli, and most subclinical infections were caused by Streptococcus dysgalactiae and coagulase-negative staphylococci. On day 6 of the cycle, cows received PGF2α; 42 h later, follicular fluids and granulosa cells or theca cells were aspirated from preovulatory follicles in vivo or following slaughter, respectively. Overall, follicular estradiol and androstenedione concentrations in the subclinical group (n = 28) were 40% lower (P < 0.05) than those in uninfected cows (n = 24) and lower than in past clinical mastitic cows (n = 9). Distribution analysis revealed a clear divergence among subclinical cows: one-third (9/28) exhibited low follicular estradiol; the other two-thirds had normal levels similar to all uninfected (P < 0.01) and most clinical cows (P < 0.08) that had normal follicular estradiol levels. Subclinical normal-estradiol cows had twofold higher (P < 0.05) circulating estradiol concentrations and sevenfold and fourfold higher (P < 0.05) follicular androstenedione levels and estradiol-to-progesterone ratio, respectively, than subclinical low-estradiol cows. Follicular progesterone level was not affected. Reduced expression (P < 0.05) of LHCGR in theca and granulosa cells, CYP11A1 (mRNA and protein) and CYP17A1 in theca cells, and CYP19A1 in granulosa cells may have contributed to the lower follicular steroid production in the subclinical low-estradiol subgroup. StAR and HSD3B1 in theca cells and FSHR in granulosa cells were not affected. Mastitis did not alter follicular growth dynamics, and no carryover effect of past clinical mastitis on follicular function was detected. These data indicate that a considerable proportion (one-third) of subclinical mastitic cows have abnormal follicular steroidogenesis, which can explain the reproductive failure associated with this disease. © 2011 Elsevier Inc.
Scientific Publication
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