Genetic analysis of retained placenta and its association with reproductive disorder, production, and fertility traits of Iranian Holstein dairy cows

Abolfazl Mahnani; Ali Sadeghi-Sefidmazgi; Saeid Ansari-Mahyari; Heydar Ghiasi; Sajjad Toghiani

doi:10.1016/j.theriogenology.2022.04.008

Genetic analysis of retained placenta and its association with reproductive disorder, production, and fertility traits of Iranian Holstein dairy cows

Theriogenology. 2022 Sep 1:189:59-63. doi: 10.1016/j.theriogenology.2022.04.008. Epub 2022 Apr 14.

Authors

Abolfazl Mahnani¹, Ali Sadeghi-Sefidmazgi², Saeid Ansari-Mahyari³, Heydar Ghiasi⁴, Sajjad Toghiani⁵

Affiliations

¹ Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, P.O. Box 84156-83111, Isfahan, Iran. Electronic address: abolfazlmahnani@gmail.com.
² Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, P.O. Box 84156-83111, Isfahan, Iran; Department of Animal Science, University of Tehran, P.O. Box 3158711167, 4111, Karaj, Iran. Electronic address: Sadeghism@iut.ac.ir.
³ Department of Animal Sciences, College of Agriculture, Isfahan University of Technology, P.O. Box 84156-83111, Isfahan, Iran.
⁴ Department of Animal Science, Faculty of Agricultural Science, Payame Noor University, Tehran, Iran.
⁵ USDA, ARS, Animal Genomics and Improvement Laboratory, Beltsville, MD, 20705, USA.

PMID: 35724453
DOI: 10.1016/j.theriogenology.2022.04.008

Abstract

To facilitate breeding for improved resistance to the reproductive disorder of retained placenta (RP), genetic parameters were estimated for RP and its genetic correlation with other reproductive disorders as well as with production and fertility traits of Iranian Holstein dairy cows. Data were 154,048 lactation records collected between 2011 and 2018 from 59,610 Holstein dairy cows in 9 Iranian herds. Other reproductive disorders included dystocia, stillbirth, and twinning. Fertility records were available for days from calving to first service (DFS), days open (DO), number of inseminations per conception (NIC), and success of first insemination (SFI). Genetic parameters for RP were estimated using univariate linear and logistic animal models with ASREML software. The univariate linear animal model was used to implement bivariate analysis to investigate potential genetic correlations of RP with other reproductive disorders and with production and fertility traits. Heritability estimates for RP were low from both linear (0.031) and logistic (0.092) animal models. Estimated genetic correlations with RP were -0.04 for twinning, 0.32 for stillbirth, and 0.34 for dystocia, which indicates that selection against RP could indirectly select against dystocia and stillbirth. Estimated genetic correlations between RP and production traits (milk, fat, and protein yields) at 100, 200, and 305 d in milk ranged from -0.12 to -0.29; the greatest correlation (-0.29) was for the first 100 d in milk. A moderate positive genetic correlation (0.25) was found for RP and DO, DFS, and NIC, whereas a low negative genetic correlation (-0.09) was found between RP and SFI. The pedigree-based genetic analysis of RP showed that this trait has a low heritability, is linked to other reproductive disorders, and generally has an unfavorable relationship with production and fertility traits. Selection against RP can reduce the incidence of reproductive disorders and improve fertility and production traits.

Keywords: Fertility; Genetic parameter; Milk production; Reproductive disorder; Retained placenta.

MeSH terms

Animals
Cattle / genetics
Cattle Diseases* / epidemiology
Cattle Diseases* / genetics
Cattle Diseases* / metabolism
Dystocia* / genetics
Dystocia* / metabolism
Dystocia* / veterinary
Female
Fertility / genetics
Iran / epidemiology
Lactation / genetics
Milk / metabolism
Placenta, Retained* / epidemiology
Placenta, Retained* / genetics
Placenta, Retained* / veterinary
Pregnancy
Stillbirth / genetics
Stillbirth / veterinary