Publikationsdatenbank

Optimizing dairy cattle genetics:
can we breed for cows with high milk yield and good fertility? (2024)

Art

Vortrag

Autoren

Madureira, A. M. L.

Borchardt, S. (WE 19)

Cerri, R. L. A.

Vasconcelos, J. L. M.

Burnett, T. A.

Kongress

ADSA Conference 2024

West Palm Beach, 16. – 19.06.2024

Quelle

Journal of dairy science : JDS

Bandzählung: 107

Heftzählung: Supplement 1

Seiten: 296

ISSN: 0022-0302

Sprache

Englisch

Verweise

URL (Volltext): https://www.adsa.org/Portals/0/SiteContent/Docs/Meetings/2024ADSA/Abstracts_BOOK_2024_FINAL.pdf

Kontakt

Tierklinik für Fortpflanzung

Königsweg 65
Haus 27
14163 Berlin
+49 30 838 62618
fortpflanzungsklinik@vetmed.fu-berlin.de

Abstract / Zusammenfassung

The objective of this study was to assess the relationship between genomic daughter pregnancy rate (gDPR), genomic merit for milk production (gMilk), and pregnancy at first AI and pregnancy losses (PL). A total of 6,739 Holstein cows (first lactation: n = 2,636; second lactation: n = 2,057; third lactation: n = 2,046) from one commercial dairy herd were included. Cows were bred following a timed AI protocol for first service at 60 ± 3 d based on estradiol and progesterone. Hair samples were collected from the tail switch, and cows were genotyped using a SNP platform (Clarifide, Zoetis). Pregnancy diagnosis was performed at d 32 and 60 after AI using ultrasonography. Pregnancy loss was defined as a pregnant cow on d 32 that was nonpregnant on d 60. Data were analyzed by using the linear mixed regression models from SAS. Cows were grouped based on their median for gDPR and gMilk into 4 groups: (1) low gDPR and low gMilk (LgDPR_LgMilk); (2) high gDPR and low gMilk (HgDPR_LgMilk); (3) low gDPR and high gMilk (LgDPR_ HgMilk); (4) high gDPR and high gMilk (HgDPR_HgMilk). There was a mild-negative correlation between gDPR and gMilk. Pregnancy per AI was affected by a combination of gDPR and gMilk. Pregnancy per AI was 40.6% ± 1.5%, 50.4% ± 1.4%, 43.1% ± 1.4%, and 53.3% ± 1.6% for cows in LgDPR_LgMilk, HgDPR_LgMilk, LgDPR_HgMilk, and HgDPR_HgMilk, respectively. Pregnancy loss was not associated with gMilk, but there was an association with gDPR. Cows with high gDPR have reduced PL compared with low gDPR cows (7.2% ± 0.6% vs. 13.5% ± 1.2%). There was a clear association of gDPR and gMilk on milk production at d 60 with 44.4 ± 0.16, 44.9 ± 0.15, 48.7 ± 0.15, and 48.4 ± 0.17 kg/d for cows in LgDPR_LgMilk, HgDPR_LgMilk, LgDPR_HgMilk, and HgDPR_HgMilk, respectively. Increase in gDPR was associated with greater odds of pregnancy per AI and lower odds of PL. High gDPR and high gMilk suggest that both genotypes could be selected for. These results provide further evidence that gDPR is
associated with better reproduction outcomes.