Placentome collection from dairy cows for research purposes and its implications for their future reproductive performance

Abstract

Introduction: Placentome in cattle comprises fetal cotyledon and maternal caruncle and is a vital site
for feto-maternal substance exchanges. There are considerable metabolic and hormonal interactions
in the placentomes that could affect the body of the fetus and the mother. Despite the importance of
this tissue in reproduction of cattle, there are few studies on this tissue probably due to worries about
the invasive trait of placentome collection and its implications for the future reproductive
performances of the cow. In this study, we described a method of placentome collection from cows
and investigated its implications for the cows’ subsequent reproductive performance.
The purpose of this study was to investigate the effect of statistical distribution of the effects of SNPs
on the biased process of estimating breeding values resulting from pre-selection of animals by
genomic selection method. The statistical distributions studied included two distributions of normal
and gamma, the biased trend of each of which was studied during consecutive generations. The bias
criterion includes the regression of actual correction values on the estimated correction values.
Materials & Methods: In this study, placentomes were collected from six cows within 30 minutes
after parturition by using a guitar string and a hygienic protocol. Then, one dose of vitamin K and two
doses of B-complex (during two days) were administered and the health status of the cows was
monitored for several days. The number of inseminations until conception, the length of open days,
the interval between two subsequent parturitions and the health status of the following calf were
recorded for each cow. These six cows considered as placentome collected group and their data were
compared to 45 cows in the same herd as control group. Cows in the control group had at most 430
days of interval between their two subsequent parturitions and underwent no manipulation.
Results: According to the results, general health of the placentome collected cows was not affected
after placentomectomy. None of the reproduction related parameters including the number of
insemination until conception, the length of open days, the interval between two parturitions and the
health status of the calves showed significant difference between the placentome collected group
compared to control. However, the interval between the first parturition and the second insemination
was significantly shorter in the cows that underwent placentome collection.
Conclusion: In this study, we described an easy and efficient method of placentome collection from
alive cows and showed that this method does not have considerable implications for the cows’
reproductive performance. Therefore, by careful collection of placentomes and by having justifiable
research purposes, placentome collection from the cows could be considered for future studies.