We tested the hypothesis that fatty acid biosynthesis and adipocyte diameter and volume would be greater in s.c. and i.m. adipose tissues of calf-fed steers than in yearling-fed steers at a constant BW, due to the greater time on feed for the calf-fed steers. Conversely, we predicted that the capacity for s.c. and i.m. preadipocytes to divide, as estimated by 3H-thymidine incorporation into DNA...

A 2-yr study was conducted using 200 long yearling steers/yr (436 ± 30 kg) to determine the effect on performance and economics of sorting by BW at feedlot entry and feeding 200 mg/steer of Optaflexx (OPT) daily for the last 28 d. At feedlot entry, steers were allotted into 1 of 4 treatments in a 2 × 2 factorial arrangement: sorted or unsorted with or without OPT. Sorted steers were placed into...

Data consisting of 948 calf records collected from 1978 to 1982 were analyzed to determine the effects of breeding methods used to improve commercial herds genetically on birth and weaning traits. Four distinct groups were used in the project: Group 1 (G1), an unselected, random mating Hereford control line; Group 2 (G2), a Hereford group using sires selected for yearling growth; Group 3 (G3), ...

We obtained heritability and (co)variance component estimates for slaughter conformation scores at 420 days of age (SCS420), age at calving (first, AFC; second, ASC), calving occurrence until 38 months of age (CP38), weight at 420 days of age (W420), and scrotal circumference at 420 days (SC420) in Canchim (5/8 Charolais + 3/8 Zebu) cattle. A total of 23,168 records of Canchim animals, includin...

The objective of this study was to evaluate effects of feeding monensin (MON) or a multivalent polyclonal antibody preparation (PAP) against several rumen microorganisms on feedlot performance, carcass characteristics, blood gas profile, and rumenitis of Bos indicus biotype (BT) yearling bulls. The study was designed as a completely randomized design with a 3 × 2 factorial arrangement, replicat...

BRODY, A. K., and K. B. ARMITAGE. 1985. The effects of adult removal on dispersal of yearling yellow-bellied marmots. Can. J. Zool. 63: 2560-2564. The relative importance of adult-yearling interaction and individual behavioral phenotypes on dispersal of yearling yellow-bellied marmots was investigated. Two marmot colonies near Gothic, Colorado, were studied; one was treated as an experimental c...

The genetic analysis of composite data is very complicated, mainly because it is necessary to adjust data to the effects of heterosis and breed complementarity, and because there is usually considerable confounding of these data with several other effects, such as contemporary group effects, breed composition of the animal and maternal breed composition, among others. Data on birth weight (n = ...