Effects of parity and early pregnancy on peripheral blood leukocytes in dairy cattle

ABSTRACT: Subfertility remains a major problem in the dairy industry. Only 35% to 40% of high-yielding dairy cows and 55% to 65% of nonlactating heifers become pregnant after their first service. The immune system plays a critical role in the establishment of pregnancy. However, it can also create c...

Full description

Saved in:
Bibliographic Details
Main Authors: M.I. da Silva, N. Oli, F. Gambonini, T. Ott
Format: Article
Language:English
Published: Elsevier 2024-12-01
Series:Journal of Dairy Science
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S0022030224010865
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1850066393728286720
author M.I. da Silva
N. Oli
F. Gambonini
T. Ott
author_facet M.I. da Silva
N. Oli
F. Gambonini
T. Ott
author_sort M.I. da Silva
collection DOAJ
description ABSTRACT: Subfertility remains a major problem in the dairy industry. Only 35% to 40% of high-yielding dairy cows and 55% to 65% of nonlactating heifers become pregnant after their first service. The immune system plays a critical role in the establishment of pregnancy. However, it can also create challenges for embryo survival and contribute to reduced fertility. We conducted 2 separate experiments to characterize changes in subsets of peripheral blood leukocytes (PBL) and their phenotype over the estrous cycle and early pregnancy in heifers and cows. We used flow cytometry and reverse transcription-quantitative PCR to assess protein and mRNA expression of molecules important for immune function. We observed that CD14+ monocytes and CD3+ T cells tended to be affected by pregnancy status in heifers, whereas CD8B+ lymphocytes and NCR1+ natural killer cells were affected during early pregnancy in cows. Changes in expression of immune function proteins appeared to be greater in heifers than cows. To compare the most striking differences between heifers and cows observed in the initial experiments, we conducted a third experiment where PBL sampled from heifers and cows were simultaneously collected and analyzed under the same experimental conditions. Our results indicate that, compared with heifers, cows had greater mRNA expression of proinflammatory cytokines (IFN-γ and IL6) and AHR protein along with greater percentage of MM20A+ neutrophils and myeloid cells expressing SIRPA, ITGAM, and ITGAX. Moreover, animals that failed to become pregnant showed altered expression of anti-inflammatory molecules compared with cyclic and pregnant animals. Overall, these findings support the hypothesis that early pregnancy signaling alters the phenotype of immune cells in the peripheral blood and that differences in the peripheral immune response to pregnancy between cows and heifers exist. Because cows have lower conception rates than heifers, it is possible that a more proinflammatory immune status in peripheral blood may play a role in embryo loss.
format Article
id doaj-art-53ca8b85caaa488f8539bc03ec90e4fd
institution DOAJ
issn 0022-0302
language English
publishDate 2024-12-01
publisher Elsevier
record_format Article
series Journal of Dairy Science
spelling doaj-art-53ca8b85caaa488f8539bc03ec90e4fd2025-08-20T02:48:45ZengElsevierJournal of Dairy Science0022-03022024-12-0110712117281174310.3168/jds.2024-25063Effects of parity and early pregnancy on peripheral blood leukocytes in dairy cattleM.I. da Silva0N. Oli1F. Gambonini2T. Ott3Department of Animal Science, Center for Reproductive Biology and Health, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA 16802Department of Animal Science, Center for Reproductive Biology and Health, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA 16802Department of Animal Science, Center for Reproductive Biology and Health, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA 16802Corresponding author; Department of Animal Science, Center for Reproductive Biology and Health, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA 16802ABSTRACT: Subfertility remains a major problem in the dairy industry. Only 35% to 40% of high-yielding dairy cows and 55% to 65% of nonlactating heifers become pregnant after their first service. The immune system plays a critical role in the establishment of pregnancy. However, it can also create challenges for embryo survival and contribute to reduced fertility. We conducted 2 separate experiments to characterize changes in subsets of peripheral blood leukocytes (PBL) and their phenotype over the estrous cycle and early pregnancy in heifers and cows. We used flow cytometry and reverse transcription-quantitative PCR to assess protein and mRNA expression of molecules important for immune function. We observed that CD14+ monocytes and CD3+ T cells tended to be affected by pregnancy status in heifers, whereas CD8B+ lymphocytes and NCR1+ natural killer cells were affected during early pregnancy in cows. Changes in expression of immune function proteins appeared to be greater in heifers than cows. To compare the most striking differences between heifers and cows observed in the initial experiments, we conducted a third experiment where PBL sampled from heifers and cows were simultaneously collected and analyzed under the same experimental conditions. Our results indicate that, compared with heifers, cows had greater mRNA expression of proinflammatory cytokines (IFN-γ and IL6) and AHR protein along with greater percentage of MM20A+ neutrophils and myeloid cells expressing SIRPA, ITGAM, and ITGAX. Moreover, animals that failed to become pregnant showed altered expression of anti-inflammatory molecules compared with cyclic and pregnant animals. Overall, these findings support the hypothesis that early pregnancy signaling alters the phenotype of immune cells in the peripheral blood and that differences in the peripheral immune response to pregnancy between cows and heifers exist. Because cows have lower conception rates than heifers, it is possible that a more proinflammatory immune status in peripheral blood may play a role in embryo loss.http://www.sciencedirect.com/science/article/pii/S0022030224010865pregnancybovineimmuneleukocytescytokines
spellingShingle M.I. da Silva
N. Oli
F. Gambonini
T. Ott
Effects of parity and early pregnancy on peripheral blood leukocytes in dairy cattle
Journal of Dairy Science
pregnancy
bovine
immune
leukocytes
cytokines
title Effects of parity and early pregnancy on peripheral blood leukocytes in dairy cattle
title_full Effects of parity and early pregnancy on peripheral blood leukocytes in dairy cattle
title_fullStr Effects of parity and early pregnancy on peripheral blood leukocytes in dairy cattle
title_full_unstemmed Effects of parity and early pregnancy on peripheral blood leukocytes in dairy cattle
title_short Effects of parity and early pregnancy on peripheral blood leukocytes in dairy cattle
title_sort effects of parity and early pregnancy on peripheral blood leukocytes in dairy cattle
topic pregnancy
bovine
immune
leukocytes
cytokines
url http://www.sciencedirect.com/science/article/pii/S0022030224010865
work_keys_str_mv AT midasilva effectsofparityandearlypregnancyonperipheralbloodleukocytesindairycattle
AT noli effectsofparityandearlypregnancyonperipheralbloodleukocytesindairycattle
AT fgambonini effectsofparityandearlypregnancyonperipheralbloodleukocytesindairycattle
AT tott effectsofparityandearlypregnancyonperipheralbloodleukocytesindairycattle