Effect of embryo quality on pregnancy outcome in recipient cows and heifers


Kara U., Çoban S., Say E., Hızlı H., Mutlu H., Nak Y., ...More

JOURNAL OF THE HELLENIC VETERINARY MEDICAL SOCIETY, vol.71, no.2, pp.2233-2240, 2020 (SCI-Expanded)

  • Publication Type: Article / Article
  • Volume: 71 Issue: 2
  • Publication Date: 2020
  • Doi Number: 10.12681/jhvms.23630
  • Journal Name: JOURNAL OF THE HELLENIC VETERINARY MEDICAL SOCIETY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, CAB Abstracts, EMBASE, Veterinary Science Database
  • Page Numbers: pp.2233-2240
  • Çukurova University Affiliated: Yes

Abstract

This study was performed to compare the effects of embryo quality on pregnancy outcome in recipient

cows and heifers. Embryos obtained from 83 Holstein donors were used in the study. In order to synchronize the recipients,

500 μg of cloprostenol were administered intramuscularly (i.m.), twice, at an interval of 11 days. In all recipients,

one embryo was transferred to the upper 1/3 of the uterine horn ipsilateral to the ovary with the corpus luteum on the

7th day after oestrus onset (day 0). Each recipient received an i.m. injection of 5 μg of buserelin at the time ofembryo

transfer. Pregnancy examinations were performed by ultrasonography on the day 30th post-transfer. A total of 345

(262 grade 1, 64 grade 2 and 19 grade 3) fresh embryos were transferred to 171 recipient cows and 174 recipient

heifers. The pregnancy rates of the recipient cows and heifers were 41.52% and 52.29%, respectively (p<0.05).The

pregnancy rates achieved with first, second and third quality grade embryos were 45.16%, 25.0% and 12.5% in the

cows (p<0.05), and 55.11%, 41.66% and 54.54% in the heifers (p>0.05), respectively. In conclusion, the pregnancy

rates was significantly higher in heifers than in cows (p<0.05) and, the embryo quality had a significant impact on

recipient pregnancy outcome (p<0.05). The effect of embryo quality on pregnancy was significant in cows (p<0.05),

but not significant in heifers (p>0.05).

Keywords: Embryo transfer, embryo quality, pregnancy rate, cows, heifers