In 1996 the Subcommittee on Beef Cattle Nutrition of the National Research Council (NRC) released the seventh revised edition of the 'Nutrient Requirements of Beef Cattle' (subsequently updated as NRC, 2000). Among the more dramatic changes with this revision was the enhanced characterization of feedstuffs with respect to composition and degradation rates of N and carbohydrate fractions, with t...

A 2-yr experiment was conducted to compare carcass characteristics and meat palatability attributes of steers ((3/4) British, (1/4) Continental) finished postweaning as calves or yearlings. Calves and yearlings of the same contemporary group were designated to a finishing system at weaning. Calves (n = 73) were finished in the feedlot (191 d) on a high-concentrate diet. Yearlings (n = 84) graze...

Over a 5-yr period, spring-calving cows were used in a carry-over design experiment to evaluate effects of calf age at weaning on cow and calf performance and production economics. Weaning management groups were early (n = 60, calf age 150 d, EW), traditional (n = 60, calf age 210 d, NW), and late (n = 60, calf age 270 d, LW). Cow body condition score (BCS) and weights at the last weaning date ...

Giardia duodenalis and Cryptosporidium parvum are parasitic protozoans and infections are common in domestic ruminants. Infections can lead to moderate to severe diarrhea with occasion mortalities. Clinical disease with Cryptosporidium parvum occurs in calves between 1 and 3 weeks of age lasting 1-2 weeks in duration. Giardiasis is observed in calves older than 3 weeks of age and is chronic. Th...

The purpose of this study was to compare the efficacy and cost-effectiveness of florfenicol versus tulathromycin for initial treatment of undifferentiated fever in fall-placed steer calves that received metaphylactic tilmicosin on arrival at the feedlot. No significant differences (P > .10) were observed in undifferentiated fever relapses or the crude case fatality rate. Calves treated with flo...

an outbreak of a lethal disease was reported in 4–6-month-old holstein calves in a feedlot around tehran. the signs of central nervous system and gastrointestinal system (gi) involvement were observed in the diseased animals. necropsy samples of gi, liver, kidney, spleen and lung from 3 died animals were prepared for histopathological examination. blood and formalin-fixed ear notch samples of 6...

Abstract This experiment evaluated the effects of multiple bovine appeasing substance administration during a 42-day preconditioning program followed by feedlot receiving period on productivity, health, and physiological variables feeder cattle. Ninety recently weaned calves were obtained from Red Bluff Ranch (Norris, MT). All weighed (prior to transport). Calves loaded into livestock trailer, ...

Birth (n = 308), weaning (n = 291), feedlot and carcass (n = 142), and yearling heifer traits (n = 139) were evaluated in F1 calves sired by Brahman (BR), Boran (BO), and Tuli (TU) bulls and born to multiparous Hereford and Angus cows. Calves sired by BR were heaviest (P < .05) at birth and largest (P < .05) for cannon bone length. Tuli crosses were smaller (P < .05) for birth weight and cannon...

The objective of this study was to characterize genetic, environmental, and economic factors related to the incidence of bovine respiratory disease (BRD) in feedlot calves. Records from 18,112 calves representing 9 breeds (Angus, Braunvieh, Charolais, Gelbvieh, Hereford, Limousin, Pinzgauer, Red Poll, and Simmental) and 3 composite types (MARC I, MARC II, and MARC III) over a 15-yr period (1987...

This study provides evidence that subcutaneous vaccination of cattle with a commercially available modified-live virus combination vaccine can help reduce clinical signs associated with infectious bovine rhinotracheitis infections in feedlot animals vaccinated at the time of arrival. Calves vaccinated 72 or 96 hours before challenge had reduced clinical signs, lower body temperatures, lower vir...