Short communication: The beef merit of the sire mated to a dairy female affects her subsequent performance

Abstract

Much of the research to date on dairy × beef matings has focused only on the greater revenue attainable from these beef-cross calves. The objective of the present study was to quantify the mean effect on cow performance following the birth of calves differing in beef merit; all calves were born without calving assistance. Beef merit in the present study was based on the breed of the sire but also its genetic merit for carcass weight and conformation. The cross-sectional study used up to 346,765 calving events from 230,255 Holstein-Friesian cows in 3,604 herds. Performance traits of interest were those associated with milk production, including somatic cell count, as well as female reproductive performance. Sire breed was associated with all yield traits, somatic cell count, and both pregnancy rate and the interval from calving to first service; no association existed with either submission rate or number of services. Relative to a Holstein-Friesian sire, the mean 305-d milk yield (in kg) was 45.22 (standard error,

The response to genetic merit for milk production in dairy cows differs by cow body weight

“…This is similar to the values of 81 to 83% documented by Berry et al (2011) and Buckley et al (2000) in populations of Irish Holstein-Friesian cows not overlapping with the data used in the present study. This ratio is also identical to the value of 77% reported for the ratio of first-parity versus mature milk yield in Irish dairy cows (Berry and Ring, 2020).…”

Dairy Producers Who Market Their Surplus Progeny as Calves Use Germplasm With Slightly Lighter and Less-Conformed Carcasses Than Producers Who Rear Their Surplus Progeny Beyond Weaning

“…Although McHugh et al (37) presented the relative prices paid for animals of different breeds and ages, the breed effects across ages were not directly comparable since the analysis of calf price data was based solely on calves born in dairy herds, while the documented prices of older animals included a combination of progeny from both dairy and beef herds. The frequency of beef breed usage presented for the different beef breeds in the present study (Table 3) is not a reflection of their frequency of use as service sires in dairy herds-this is discussed elsewhere (38); what it does demonstrate, however, is that Belgian Blue sires are more likely to be used in dairy herds that sell their surplus progeny as calves as opposed to post-weaning. Nonetheless, the actual frequency of usage of Belgian Blue sires in the different systems was still low, varying from 3.0% in herds that sold surplus progeny as yearlings to 6.4% in herds that sold surplus progeny as calves (Table 3); the difference in frequency was largely due to a displacement of other continental sire breeds (i.e., Charolais, Limousin, and Simmental), with Belgian Blues in the latter system.…”

Service Sire Effects on Body Condition Score, Milk Production, and Rebreeding of Mixed-Aged Dairy Cows Bred to Angus and Hereford Bulls—A Case Study in New Zealand

“…3 Days from planned start of calving. 4 Predicted for a 253-day lactation (between day 15 and 267 of lactation). There was an effect of service sire on the calving day, where the service sire least squares means had a range of 13.2 days (p < 0.001, Table 1; Figure 2); however, this did not translate into a difference in the days in milk among service sires (p = 0.888).…”

“…New Zealand dairy herds are usually spring-calving and have a mean replacement rate of 22% [1,2], with replacements usually generated by breeding about 60% of the herd to high-genetic-merit, dairy-breed bulls. The remaining cows in the herd are often bred to beef-breed bulls, to produce a calf of greater value for beef production than that of a calf sired by a dairy bull [3][4][5]. These cows would typically be the later-mated cows as it is desirable to generate replacements from cows calving in the first 6 weeks [6].…”

“…There is limited research [4] about what type of beef-breed bulls are most appropriate to use in terms of any impact the service sire has on milk production, inter-calving interval, and pregnancy rate, which must be considered alongside calf value. Angus and Hereford are the predominant beef breeds in New Zealand [7], with Hereford bulls anecdotally used more commonly in the dairy industry than Angus [1].…”