Effect of calf sex on some productive, reproductive and health traits in Holstein cows

Abstract

<p>Records of Holstein cows from March 1992 to April 2008 from 194 large herds and comprising from 402,716 records for productive traits to 178,344 records of somatic cell count were used to study the effect of calf sex in different parities and calving season on the subsequent productive, reproductive and health traits in Holstein cows. T-test procedure of SAS software was used to investigate the effect of calf sex and season of calving on aforementioned traits. Cows with female calves had higher milk and fat yield, persistency of milk and fat yield and longer lactation length, while cows that gave birth to male calves had shorter calving interval and longer productive life. Also, cows with female calves had higher milk yield per day of lactation in the first two parities, but there was no difference in milk yield per day of lactation for parities ≥ 3. There was no relationship among mean somatic cell count and sex of born calf. Fall calves had the highest adjusted milk yield and milk yield per day of lactation, however, winter calves had the longest lactation lengthand productive life and the highest somatic cell count. Results from this study demonstrate that it seems necessary to consider the effect of calf sex on aforementioned traits when making decision to use sexed semen or conventional semen.</p>

Effect of Calf Gender on Milk Yield and Fatty Acid Content in Holstein Dairy Cows

“…In agreement with the present study, three previous studies have shown favourable yields when a heifer calf is born to a primiparous dam,[6–8] whilst three studies have shown dams calving bulls at the start of second lactation have higher yields. [9–11] In any case, reported effects are always marginal- the 2.7% advantage for two heifer calves born in the first two lactations found by Hinde et al6 is the largest reported by far.…”

“…Animals delivering female calves at both first and second lactations produced 454kg (2.7%) more milk than those delivering two bull calves. Canadian data agreed, but demonstrated a much smaller effect of less than 0.5%,[7] and Iranian data[8] also showed higher milk production in dams giving birth to heifers for up to four parities. The yield advantage conferred by heifer calves was only seen in the second lactation in New Zealand Holstein-Friesians,[9] and only in the first lactation in French Holstein-Friesians.…”

The Effect of Calf Gender on Milk Production in Seasonal Calving Cows and Its Impact on Genetic Evaluations

“…Hinde et al [ 6 ] showed that U.S. Holstein dams that gave birth to daughters had higher milk yields than dams that gave birth to sons, and that first parity calf gender affected milk yield in subsequent lactations. The Canadian [ 7 ] and Iranian [ 9 ] studies also observed higher milk yields in Holstein dams that gave birth to a daughter rather than a son; however the effects were larger than those observed in U.S. Holsteins in the Iranian study and smaller in the Canadian study. First and second parity calf gender influenced milk yield in both first and second lactations in the Canadian study [ 7 ].…”

“…Calf gender has been shown to affect milk yield in U.S. [ 6 ], Canadian [ 7 ], French [ 8 ], Iranian [ 9 ] and Danish [ 10 ] dairy cattle populations. Hinde et al [ 6 ] showed that U.S. Holstein dams that gave birth to daughters had higher milk yields than dams that gave birth to sons, and that first parity calf gender affected milk yield in subsequent lactations.…”

“…The French and Canadian studies concluded that although there may be some effect of calf gender on dam milk yield, it was not large enough to impact profit [ 8 ] or encourage use of sexed semen [ 7 ]. However, the size of the effect in the Iranian study led to the conclusion that the effect of calf gender on milk yield needs to be accounted for when considering the use of sexed semen [ 9 ].…”