Bioeconomics of sexed semen utilization in a high-producing Holstein-Friesian dairy herd

Abstract

A bioeconomic, stochastic spreadsheet model, that included calculation of the net present value of the additional value of all future descendants resulting from increased selection intensity, was developed to study the profitability of using sexed semen in a high input-high output dairy herd. Three management strategies were modeled: (1) only heifers inseminated with sex-sorted semen and cows inseminated with unsorted semen; (2) both heifers and cows inseminated with sex-sorted semen; and (3) a reference scenario, in which all breeding females were inseminated with unsorted semen. A Monte Carlo simulation (@risk software, Palisade Corp., Ithaca, NY) was run to study the sensitivity of net profit and sexed semen advantage to key input parameters. Most input parameters were given truncated normal distributions, whereas the maximum numbers of inseminations in heifers and cows were given discrete distribution functions. The calculated intensity of selection accounted for the different numbers of dairy females born for each of the 100,000 iterations. Using sexed semen (X-sorted, female) was shown to be profitable, with insemination of both heifers and cows being most profitable. The returns on assets were higher when only heifers were inseminated with sexed semen (8.54% ± 2.94; ±SD) or all females were inseminated with sexed semen (8.85% ± 2.93) than when all females were inseminated with unsexed semen (8.38% ± 2.95). The range in net profit was most sensitive to the assumed distributions of milk protein price (€/kg), milk fat price (€/kg), cow pregnancy rate, fertilizer price (€/t), and concentrate price (€/t) when unsorted semen was used. When only heifers or both heifers and cows were inseminated with sex-sorted semen, the range in net profit was most sensitive to the same distributions, with fertilizer price and cow pregnancy rate in reverse order of sensitivity. However, the range in sex-sorted semen advantage (in net profit) when only heifers were inseminated with sex-sorted semen was most sensitive to the assumed distributions of cow pregnancy rate, sex-sorted semen pregnancy rate as a percent of unsorted semen rates, standard deviation of index, additional cost of sex-sorted semen (€/dose), dairy bull calf price (€/head), and dairy heifer calf price (€/head). When both heifers and cows were inseminated, the order of importance of the last 2 inputs was reversed. This study highlights the relatively high effect of pregnancy rate and the genetic value of dairy bulls in determining the level of financial advantage from using sex-sorted semen in a dairy herd.

Effect of delaying the time of insemination with sex‐sorted semen on pregnancy rate in Holstein heifers

“…Male calves generally have a little economic income in the dairy herds; thus, the use of sex‐sorted semen is preferred for increasing the number of female calves which are used as replacement heifers afterwards (Cottle, Wallace, Lonergan, & Fahey, 2018; Crites et al., 2018). Besides, several studies have reported that sex‐sorted semen increases economic profitability (Chebel, Guagnini, Santos, Fetrow, & Lima, 2010) and that sex‐sorted semen technology had also considerable benefits such as acceleration genetic gain (Hohenboken, 1999), enhanced herd biosecurity (Cottle et al., 2018), lower animals participating in the progeny test (De Vries et al., 2008) and reduction in the incidence of dystocia (Holden & Butler, 2018). The lower fertility of sex‐sorted semen is the main factor that limits widespread use in dairy herds (DeJarnette et al., 2011), which has been discussed in many reviews (Grant & Chamley, 2007; Holden & Butler, 2018; Seidel, 2007; Vishwanath & Moreno, 2018).…”

Intensive use of IVF by large-scale dairy programs

“…However, studies show that the blastocyst rates are lower than those obtained with conventional semen (Seidel Jr. 2014). On the other hand, Cottle et al (2018) identified a significant profit advantage for using sexed semen in the context of a high-output, dairy system of spring births in Ireland. The authors concluded that the use of sexed semen is more appropriate for those farms that already have an excellent fertility performance.…”

“…The authors concluded that the use of sexed semen is more appropriate for those farms that already have an excellent fertility performance. Thus, the lowest rates associated with sexed semen can be less acceptable for farms with sub-optimal dairy herds fertility (Cottle et al, 2018).…”

Bovine sperm-oviduct interactions are characterized by specific sperm behaviour, ultrastructure and tubal reactions which are impacted by sex sorting

“…The process enables the separation of X-and Y-bearing spermatozoa with 90% accuracy, allows farmers to maintain their herds without having to buy cows from other sources and increases herd milk production through the manipulation of sex ratios 33,46 . However, sorting takes approximately 50 h to sort through a single bull ejaculate (sorting speed: 30,000 sperm/s) and the resulting straws are more expensive than unsorted straws 46,47 . Further to that, there is a 7.5-fold decrease in the sperm concentration of sexed straws as sperm are diluted due to sorting and centrifugation and 50% of the sperm are discarded 48 .…”