Embryonic mortality in Holstein cows on one's farm

Abstract

The objective of our research was to evaluate the effect of some factors on the embryonic mortality of Holstein-Friesian dairy cows in a herd. Monitoring was conducted in the course of three years (2006–2009) at a level of (9330–8970) kg/dairy cow per lactation. We monitored the reproduction parameters of 209 dairy cows (1st to 8th lactation). Ultrasonography was used to diagnose gravidity, and/or embryonic mortality, in each cow 6 times, at regular 4-day intervals between days 22 and 42 after insemination. We analysed the effect of 3 factors on embryonic mortality: age, body condition score and season of the year at the time of insemination. Embryonic mortality relative to the age of the female was significantly the lowest (20.69 %) in cows aged 42 to 47 months (3.5–3.9 years); high embryonic mortality (45.46 %) was recorded in the youngest females of 24 to 29 months of age (2.0–2.4 years). The results indicated that the body condition score of the cow at the time of insemination had a statistically significant (P > 0.01) effect on embryonic mortality (EM). Embryonic mortality was the lowest when the body condition of the cow was “ideal”, i.e. 5 points of the BCS (at the most 9 points). The season of the year when insemination was carried out had a positive effect on embryonic mortality.