|Bjelland, D. -|
|Weigel, K. -|
|Hoffman, P. -|
|Esser, N. -|
|Halbach, T. -|
Submitted to: Journal of Dairy Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 7, 2011
Publication Date: September 22, 2011
Citation: Bjelland, D.W., Weigel, K.A., Hoffman, P.C., Esser, N.M., Coblentz, W.K., Halbach, T.J. 2011. Production, reproduction, health, and growth traits in backcross holstein x jersey cows and their holstein contemporaries. Journal of Dairy Science. 94:5194-5203. Interpretive Summary: Over the past several decades, average milk production per cow has increased substantially, but many health and fertility traits have become less desirable. Interest in crossbreeding has grown among many producers as a technique for improving these lagging traits. Oftentimes, Jerseys are thought to the best complement for purebred Holsteins because of their adavantages in milk composition and reproductive fertility.A total of 648 purebred Holstein and 319 backcross Holstein x Jersey dairy cattle were compared for production, health, linear type, and growth traits within the University of Wisconsin Intergrated Dairy Facility, located at Marshfield and Arlington, WI. Control Holsteins exhibited greater milk production traits than the backcross cows; however, days open and services per conception as heifers or later as cows did not differ between Holsteins and backcrosses. Results of this study suggest that backcross Holstein x Jersey cows will exhibit decreased milk production, but also fail to demonstrate improvements in health and reproductive traits compared to purebred Holsteins.
Technical Abstract: A total of 648 purebred Holstein and 319 backcross Holstein × Jersey dairy cattle were compared for production, reproduction, health, linear type, and growth traits. Animals were born between 2003 and 2009 and were housed in the University of Wisconsin–Madison Integrated Dairy Facility. All animals had Holstein dams; lactating dams were mated to unproven Holstein sires to produce purebred (control) Holsteins or to unproven (F1) Jersey × Holstein crossbred sires to produce backcross animals, whereas nulliparous dams were mated to proven Holstein sires to produce purebred (other) Holsteins. Traits were analyzed using mixed linear models with effects of season of birth, age of dam, sire, birth year of sire, days in milk, lactation, and linear type score evaluator. Control Holsteins had greater 305-d milk yield (12,645 vs. 11,456 kg), 305-d mature equivalent milk yield (13,420 vs. 12,180 kg), peak daily milk yield (49.5 vs. 46.4 kg), total lactation milk yield (11,556 vs. 10,796 kg), and daily fat-corrected milk yield (43 vs. 40 kg) compared with backcrosses. Days open and services per conception as a heifer or cow did not differ between control Holsteins, other Holsteins, or backcrosses. The proportion of first-parity births that required assistance was less in control Holsteins than in backcross cows (3.7 vs. 11.2%). The incidence of scours or respiratory problems in calves did not differ between control Holsteins, other Holsteins, and backcrosses, nor did the incidence of mastitis, injury, or feet problems. Control Holstein heifers were heavier (629 vs. 557 kg), with greater hip height (145 vs. 139 cm), body length (167 vs. 163 cm), heart girth (205 vs. 198 cm), and hip width (54 vs. 53 cm) at 22 mo of age. On a 50-point scale for linear type traits, Holsteins were larger in stature compared with backcrosses (41 vs. 28), had wider rumps (37 vs. 33), and wider rear udders (34 vs. 32). Results of this study suggest that backcross Holstein × Jersey cattle have decreased production but fail to demonstrate an advantage in health and reproduction compared with purebred Holsteins.