Effect of beef heifer development systems utilizing corn residue and late summer planted cover crops on growth, reproductive performance, and economics.

The objective of this study was to evaluate growth and reproductive performance of heifers developed using 3 different winter systems in the midwestern U.S. Spring-born heifers (n = 1,156; 214 d of age; SD ± 17 d) were used in a 3-yr study to evaluate performance in winter development systems, which utilized cover crop (CC) and corn residue grazing.

Disrupted one-carbon metabolism in heifers negatively affects their health and physiology.

The objective of this study was to determine the dose-dependent response of one-carbon metabolite (OCM: methionine, choline, folate, and vitamin B12) supplementation on heifer dry matter intake on fixed gain, organ mass, hematology, cytokine concentration, pancreatic and jejunal enzyme activity, and muscle hydrogen peroxide production. Angus heifers (n = 30; body weight [BW] = 392.6 ± 12.

Predicting feed intake in confined beef cows.

Six existing equations (three for nonlactating and three for lactating; NRC, 1987, Predicting feed intake of food-producing animals. Washington, DC: The National Academies Press, National Academy of Science; doi: 10.17226/950; NRC, 1996, Nutrient requirements of beef cattle, 7th Revised Edition: Update 1996.

Late gestational nutrient restriction in primiparous beef females: Performance and metabolic status of lactating dams and pre-weaning calves.

Fall-calving primiparous beef females [body weight (BW): 451 ± 28 (SD) kg; body condition score (BCS): 5.4 ± 0.7] were individually-fed 100% (control; CON; n = 13) or 70% (nutrient restricted; NR; n = 13) of estimated metabolizable energy and metabolizable protein requirements from day 160 of gestation to calving.

Rumen and cecum bacteria of beef cattle that differ in feed efficiency fed a forage diet.

Most of the research addressing feed efficiency and the microbiota has been conducted in cattle fed grain diets, although cattle evolved to consume forage diets. Our hypothesis was that the bacteria in the rumen and cecum differed in cattle that have a common feed intake but had different ^average daily body weight gains (ADG) on a forage diet. Heifers (n = 134) were 606 ± 1 d of age and weighed 476 ± 3 kg at the start of the 84-d feeding study.