HOME HELP FEEDBACK SUBSCRIPTIONS ARCHIVE SEARCH TABLE OF CONTENTS		QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Belcher, C. G. Articles by Frahm, R. R. Search for Related Content PubMed Articles by Belcher, C. G. Articles by Frahm, R. R.

Productivity of Two-Year-Old Crossbred Cows Producing Three-Breed Cross Calves¹

Oklahoma Agricultural Experiment Station, Stillwater 74074

Abstract

Production data from 434 2-year-old cross-bred cows and performance data to weaning from their 334 three-breed cross calves were analyzed. Crossbred females were produced from 1973 to 1975 by matings of Hereford (H), Angus (A), Simmental (S), Brown Swiss (B) and Jersey (J) bulls to H and A cows. These two-breed cross females were mated to Red Poll and Shorthorn bulls to produce their first calves at 2 years of age.

Generally, J cross and BA cows were most productive as 2-year-olds. Ninety percent of J cross cows exposed to breeding weaned a calf while only 53% of the SH cows weaned calves. Heaviest calves (P<.05) at weaning were produced by BA cows (203 kg) and the lighest calves (P<.05) by HA reciprocal crosses (168 kg). J cross and BA cows were 47 kg (37.4%) more productive in terms of kilograms of calf weaned per cow exposed when compared to HA and AH cows. SH cows weaned 24 fewer kilograms of calf per cow exposed (19.7%) than HA reciprocal crosses. Individual cow efficiency, measured by calf weaning weight divided by cow weight or cow metabolic weight favored J crosses by 18 to 20%, B crosses by 10 to 15% and S crosses by 0 to 5% over HA and AH cows.

Lactational performance was measured on 56 2-year-old crossbred cows by machine milkout techniques. Daily milk yields were highest for B crosses (7.50 kg/day) and lowest (P<.05) for HA reciprocal cross cows (4.35 kg/day). Butterfat yields favored B and J crosses (.268 kg/day) over S cross cows (.214 kg/day) and HA reciprocal crosses (.159 kg/day).

¹ Journal Article 3576 of the Agr. Exp. Sta., Oklahoma State Univ., Stillwater. Research was conducted by the Animal Science Dept. (Project 1502) in cooperation with USDA, SEA, Southern Region and contributes to the Regional Beef Cattle Breeding Project, NC-1.