The contribution of dairy steers to the U.S. fed beef supply has increased from 6.9% to 16.3% over the last two decades; in part, due to declining beef cow numbers and the increased use of sexed dairy semen to produce genetically superior replacement heifers from the best dairy cows. Raising dairy cattle for beef production offers unique opportunities and challenges when compared with feeding cattle from beef breeds. Dairy steers offer predictable and uniform finishing cattle performance (ADG, DMI, G:F) as a group and more desirable quality grades on average compared with their beef steer counterparts. However, dairy steers have lesser dressing percentages and yield 2%-12% less red meat compared with beef steers due to a greater ratio of bone to muscle, internal fat, organ size, and gastrointestinal tract weight. In addition, carcasses from dairy steers can present problems in the beef packing industry, with Holstein carcasses being longer and Jersey carcasses being lighter weight than carcasses from beef breeds. Beef × dairy crossbreeding strategies are being implemented on some dairy farms to increase the income generated from dairy bull calves, while beef × dairy crossbreeding strategies can also improve the G:F and red meat yield of beef produced from the U.S. dairy herd. This alternative model of beef production from the dairy herd is not without its challenges and has resulted in variable results thus far. Successful adoption of beef × dairy crossbreeding in the cattle industry will depend on the proper selection of beef sires that excel in calving ease, growth, muscling, and marbling traits to complement the dairy genetics involved in beef production.
The number of dairy steers contributing to the U.S. fed beef supply has increased from 6.9% to 16.3% over the last two decades. Raising dairy cattle breeds for beef production offers unique opportunities and challenges when compared with feeding beef cattle breeds. Dairy steers offer predictable and uniform finishing cattle performance (ADG, DMI, G:F) as a group and more desirable quality grades on average compared with their beef steer counterparts. Dairy steers yield less red meat compared with beef steers due to a greater ratio of bone to muscle, internal fat, organ size, and gastrointestinal tract weight. The use of growth-promoting technologies such as hormonal implants and β-adrenergic agonists can help improve finishing cattle performance and increase the red meat yield of dairy-influenced steers. In addition, beef × dairy crossbreeding strategies are being implemented on some dairy farms to increase the income generated from bull calves, while beef × dairy crossbreeding strategies can also improve the gain:feed and red meat yield of beef produced from the U.S. dairy herd. Successful adoption of beef × dairy crossbreeding in the cattle industry will depend on the proper selection of beef sires to complement the challenges and opportunities experienced with dairy genetics for beef production. Early calfhood management practices should be investigated further to determine their impacts on the subsequent finishing performance and carcass characteristics of calves produced by dairy farms for beef production.

The UK dairy herd is predominantly of the Holstein-Friesian (HF) breed, with a major emphasis placed on milk yield. Subsequently, following years of continued single-trait selection, the beef production potential of dairy bred calves has declined. Thus, male HF calves are commonly seen as a by-product of the dairy industry. Limited markets, perceived low economic value and high rearing costs mean that these surplus calves are often euthanised shortly after birth or exported to the EU for further production. Welfare concerns have been raised regarding both euthanasia and long distance transportation of these calves. Furthermore, total UK beef consumption increased by 8.5% from 2009 to 2019. Thus, in light of this growing demand, beef from the dairy herd could be better utilized within the UK. Therefore, the potential for these calves to be used in a sustainable, cost-effective beef production system with high welfare standards within the UK requires investigation. Thus, the aim of this review was to evaluate both steer and bull beef production systems, examining the impact on performance, health, welfare, and economic potential to enable a sustainable farming practice, while meeting UK market requirements. The principal conclusions from this review indicate that there is the potential for these calves to be used in UK based production systems and meet market requirements. Of the steer production systems, a 24 month system appears to achieve a balance between input costs, growth from pasture and carcass output, albeit the literature is undecided on the optimum system. The situation is similar for bull beef production systems, high input systems do achieve the greatest gain in the shortest period of time, however, these systems are not sustainable in volatile markets with fluctuating concentrate prices. Thus, again the inclusion of a grazing period, may increase the resilience of these systems. Furthermore, production systems incorporating a period at pasture are seen to have animal welfare benefits. The main welfare concern for surplus dairy bred calves is often poor colostrum management at birth. While in steer systems, consideration needs to be given to welfare regarding castration, with the negative impacts being minimized by completing this procedure soon after birth.

Daily rumination time (RT; min/d) is recognized as an important tool for assessing the health of dairy cows, which may depend on the disease, lactation stage and individual cows. Using a systematic review-meta-analysis, this study evaluated whether the variation in RT is effective for early detection of metritis and subclinical ketosis (SCK) in dairy cows in the pre and post-partum periods (from three weeks before to three weeks after calving). The research was carried out in four electronic databases - Scopus, Science Direct, Pubmed and Web of Science. The main inclusion criteria were original research; evaluation of RT in dairy cows; and use of RT for early identification of metritis and/or SCK in post-partum dairy cows. A random effect meta-analysis (MA) was conducted for each disease (metritis and SCK) separately, with the RT means of healthy and sick groups, measured in the pre and post-partum. The effect size used was the mean difference (MD).Twenty-two trials from six studies were included in the MA, involving 1494 dairy cows. For metritis, four trials from three studies in the pre-partum period were considered as well as five trials from four studies in the post-partum. For SCK, six trials from four studies pre-partum and seven trials from five studies in the post-partum period were taken into consideration. The heterogeneity between studies for metritis was null (I2 = 0%) and low (I2 = 5.7 %) in the pre-partum and in the post-partum, respectively. The MD of RT between healthy cows and those with metritis was different in the pre (MD =0.411 min/d; P < 0.001) and in the post-partum (MD =0.279 min/d; P < 0.001). In SCK, heterogeneity was high in the pre (I2 = 69 %) and in the post-partum (I2 = 58.1 %), and the MD of RT was similar between healthy and sick cows (P> 0.05). In a meta-regression, RT from primiparous cows showed a lower predicted value for MD (0.48 min. d; P < 0.05) compared to multiparous cows, and the increment in each unit of milk production decreased the predicted MD value by 0.08 min. d (P < 0.001). Our MA demonstrates that RT is a good predictor for early detection of metritis in pre and post-partum; however, it is not an adequate predictor for SCK. Further investigations using more frequent blood sampling and the same threshold values for BHB are required to assess the adequacy of rumination time to predict SCK.