Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2021 Jul 14:12:699550.
doi: 10.3389/fgene.2021.699550. eCollection 2021.

Identification of Genomic Regions Influencing N-Metabolism and N-Excretion in Lactating Holstein- Friesians

Hanne Honerlagen  1 , Henry Reyer  1 , Michael Oster  1 , Siriluck Ponsuksili  1 , Nares Trakooljul  1 , Björn Kuhla  2 , Norbert Reinsch  3 , Klaus Wimmers  1   4
Affiliations

Identification of Genomic Regions Influencing N-Metabolism and N-Excretion in Lactating Holstein- Friesians

Hanne Honerlagen et al. Front Genet. .

Abstract

Excreted nitrogen (N) of dairy cows contribute to environmental eutrophication. The main N-excretory metabolite of dairy cows is urea, which is synthesized as a result of N-metabolization in the liver and is excreted via milk and urine. Genetic variation in milk urea (MU) has been postulated but the complex physiology behind the trait as well as the tremendous diversity of processes regulating the N-metabolism impede the consistent determination of causal regions in the bovine genome. In order to map the genetic determinants affecting N-excretion, MU and eight other N-excretory metabolites in milk and urine were assessed in a genome-wide association study. Therefore phenotypes of 371 Holstein- Friesians were obtained in a trial on a dairy farm under near commercial conditions. Genotype data comprised SNP information of the Bovine 50K MD Genome chip (45,613 SNPs). Significantly associated genomic regions for MU concentration revealed GJA1 (BTA 9), RXFP1, and FRY1 (both BTA 12) as putative candidates. For milk urea yield (MUY) a promising QTL on BTA 17 including SH3D19 emerged, whereas RCAN2, CLIC5, ENPP4, and ENPP5 (BTA 23) are suggested to influence urinary urea concentration. Minor N-fractions in milk (MN) may be regulated by ELF2 and SLC7A11 (BTA 17), whilst ITPR2 and MYBPC1 (BTA 5), STIM2 (BTA 6), SGCD (BTA 7), SLC6A2 (BTA 18), TMCC2 and MFSD4A (BTA 16) are suggested to have an impact on various non-urea-N (NUN) fractions excreted via urine. Our results highlight genomic regions and candidate genes for N-excretory metabolites and provide a deeper insight into the predisposed component to regulate the N-metabolism in dairy cows.

Keywords: GWAS; cattle; emission; milk urea; nitrogen; non-urea nitrogen.

PubMed Disclaimer

Conflict of interest statement

The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

FIGURE 1
FIGURE 1
Genome-wide association analysis of urea traits: (A) milk urea, (B) milk urea yield and (C) urinary urea. The red line indicates the threshold for suggestive significance. Genes with a suggested positional or biological association to the trait are indicated in red. Genes, located closest to the right and left of the lead SNP in a 1-Mb window are colored in black.
FIGURE 2
FIGURE 2
Genome-wide association analysis of non-urea-nitrogen traits: (A) milk nitrogen, (B) uric acid and (C) allantoin. The red and green lines indicate suggestive and genome-wide significance thresholds, respectively. Genes with a suggested positional or biological association to the trait are indicated in red and green. Genes located closest to the right and left of the lead SNP in a 1-Mb window are colored in black.
FIGURE 3
FIGURE 3
Genome-wide association analysis of non-urea-nitrogen traits: (A) hippuric acid, (B) creatine and (C) creatinine. The red and green lines indicate suggestive and genome-wide significance thresholds, respectively. Genes with a suggested positional or biological association to the trait are indicated in red. Genes, located closest to the right and left of the lead SNP in a 1-Mb window are colored in black.
See this image and copyright information in PMC

References

    1. Abdoun K., Stumpff F., Martens H. (2006). Ammonia and urea transport across the rumen epithelium: a review. Anim. Health Res. Rev. 7 43–59. 10.1017/S1466252307001156 - DOI - PubMed
    1. Aguilar M., Hanigan M. D., Tucker H. A., Jones B. L., Garbade S. K., Mcgilliard M. L. (2012). Cow and herd variation in milk urea nitrogen concentrations in lactating dairy cattle. J. Dairy Sci. 95 7261–7268. 10.3168/jds.2012-5582 - DOI - PubMed
    1. Balcells J., Guada J. A., Castrillo C., Gasa J. (1991). Urinary excretion of allantoin and allantoin precursors by sheep after different rates of purine infusion into the duodenum. J. Agric. Sci. 116 309–317.
    1. Bouwman A., Schopen G., Bovenhuis H., Visker M., Van Arendonk J. (2010). Genome-wide scan to detect quantitative trait loci for milk urea nitrogen in Dutch Holstein-Friesian cows. J. Dairy Sci. 93 3310–3319. 10.3168/jds.2009-2829 - DOI - PubMed
    1. Brazert M., Kranc W., Nawrocki M. J., Sujka-Kordowska P., Konwerska A., Jankowski M., et al. (2020). New markers for regulation of transcription and macromolecule metabolic process in porcine oocytes during in vitro maturation. Mol. Med. Rep. 21 1537–1551. 10.3892/mmr.2020.10963 - DOI - PMC - PubMed