A Crossbreeding Experiment with Dairy Cattle

· U.S. Department of Agriculture
E-bog
127
Sider
Bedømmelser og anmeldelser verificeres ikke  Få flere oplysninger

Om denne e-bog

In 1939, when the Bureau of Dairy Industry began its crossbreeding experiment at Beltsville, the published information on the crossbreeding of dairy cattle was slight, unimpressive, and very little of it was based on experimental results. The crossbreeding investigations at Beltsville were undertaken to develop knowledge on the subject which would provide a sound basis for advising the operators of milk-producing farms what to expect if they used crossbreeding in hopes of producing better replacements for their milking herds. Final results on any dairy cattle breeding research project cannot be published until the last animal on the project has died, so this report covers the breeding performance and milk and butterfat production on all individuals used on the project which have had time to complete a normal first-lactation period.

Bedøm denne e-bog

Fortæl os, hvad du mener.

Oplysninger om læsning

Smartphones og tablets
Installer appen Google Play Bøger til Android og iPad/iPhone. Den synkroniserer automatisk med din konto og giver dig mulighed for at læse online eller offline, uanset hvor du er.
Bærbare og stationære computere
Du kan høre lydbøger, du har købt i Google Play via browseren på din computer.
e-læsere og andre enheder
Hvis du vil læse på e-ink-enheder som f.eks. Kobo-e-læsere, skal du downloade en fil og overføre den til din enhed. Følg den detaljerede vejledning i Hjælp for at overføre filerne til understøttede e-læsere.