|Wright, Janice - Jan|
Submitted to: Journal of Dairy Science
Publication Type: Abstract only
Publication Acceptance Date: 4/12/2002
Publication Date: N/A
Citation: Interpretive Summary:
Technical Abstract: The extent of artificial insemination (AI) use was determined for Ayrshire, Brown Swiss, Guernsey, Holstein, and Jersey breedings since 1959. Yield deviations for milk, fat, and protein of daughters of progeny- test (PT) bulls were compared with those of daughters of AI-proven bulls and natural-service (NS) bulls available at the same time/ contemporaneously. Bulls were categorized as 1) PT through a major AI organization, 2) PT through a minor AI organization, 3) proven through a major AI organization, 4) proven through a minor AI organization, 5) marketed through AI based on an NS evaluation, or 6) used through NS. Results reported are for Holsteins. The percentages of daughters that first calved in 1998 with lactation records used in USDA genetic evaluations were 15, 2, 63, 12, 2 and 6% for bulls in categories 1 through 6, respectively. Percentage of daughters sired by PT bulls increased from 8% in 1984 to 17% in 1998, while the percentage sired by bulls brought into AI based on NS daughters decreased from 19 to 2%, and percentage of NS daughters dropped from 12 to 6%. The percentage of daughters of AI- proven bulls increased somewhat (61 up to 75%). These changes were caused by a large reduction in the number of bulls entering AI based on a NS proof, plus a moderate increase in the percentage of AI use and herds participating in PT sampling. During the period 1984 to 1998, Holstein daughters of AI-proven bulls annually produced 107 to 199 kg more milk and 2 to 5 kg more fat and protein than PT daughters and 366 to 443 kg more milk, 10 to 14 kg more fat, and 9 to 11 kg more protein than NS daughters based on mean yield deviations. Use of AI in place of NS would increase annual income of producers by approximately $96 per cow.