The relationship between fertility and intermediate optimum type traits in Polish Holstein-Friesian cows

Conformation traits of Holstein cows and their association with a Canadian economic selection index

“…Zink et al (2014) showed that deeper animals tend to perform poorly for fertility traits, with unfavorable genetic correlations increasing from first to second lactation for days open (0.14 to 0.37) and first service to conception (0.23 to 0.43), suggesting that a deeper animal would stay open for more days and would take longer to conceive. Jagusiak et al (2014) reported corroborating results, finding that daughters of bulls with a higher breeding value for BD had worse nonreturn rates in primiparous cows, with an unfavorable genetic correlation of -0.41, implying that deeper daughters would need to be re-bred more times than shallower daughters. While conception is delayed and calving interval lengthens due to unsuccessful inseminations, Can.…”

“…Body depth appeared to contribute the most to lowering Pro$ index value, decreasing Pro$ by −$61.95 for every increase in one unit of RBV for BD, meaning that deeper animals are associated with a lower Pro$ index value. The contribution that BD has on other traits such as feed effciency (Manafiazar et al 2016), longevity (Zavadilová and Stipkova 2012), and fertility (Jagusiak et al 2014) in dairy cows could be a possible explanation to this effect. A recent study on the feed efficiency of dairy cows (Manafiazar et al 2016) showed that inefficient animals with high residual feed intake and high dry matter intake (DMI) tend to have greater body size, including a deeper body.…”