Bovine coronavirus infects feedlot cattle and is associated with an increased risk for cattle developing respiratory tract disease and pulmonary lesions. Development of appropriate control measures could help reduce the incidence of respiratory tract disease.

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Forty-eight steers were used to study the influence of feeding soybean oil (SO) on the conjugated linoleic acid (CLA) content of beef. Steers were fed either a control diet containing 954 g/kg of dry matter (DM) corn-based concentrate (CTL) or a control diet supplemented with SO at 20 (SO2) or 40 g/kg (SO4) of diet DM for 105 days. Adipose tissue samples were collected from the M. longissimus dorsi (LD) and from the M. semitendinosus (ST) on days 0 and 63 of the experiment. Adipose and muscle tissue samples were collected from the LD and ST immediately after slaughter. Feeding 40 g/kg of DM as SO increased the proportions of trans-C(18:1) in beef lipid as compared to CTL and SO2 treatments. The C(18:2) cis-9, trans-11 isomer of CLA as a proportion of total fat was not different in adipose and muscle across treatments. Supplementing SO increased C(18:2) trans-10, cis-12 CLA in adipose tissue of the LD. Supplementing high-grain finishing diets with SO is not an effective strategy to enhance the C(18:2) cis-9, trans-11 isomer of CLA in beef.

Twenty-four Holstein-Friesian dairy cows (20 intact and 4 fitted with rumen cannula) during early lactation (56 +/- 25.3 d in milk) were assigned to two treatments to determine intake and production responses to feeding dried and wet brewers' grain. There were two cows fitted with a rumen cannula in each treatment. Cows were fed a total mixed ration twice daily containing either dried or wet brewers' grain at 15% of the dietary dry matter (DM). The diet contained 47% forage and 53% concentrate. The experimental design was a replicated 2 x 2 Latin square with two periods of 5 wk each. First 2 wk in each period were considered as adaptation to diets and data from the last 3 wk were used for treatment comparisons. Dried and wet brewers' diets contained 68.0 and 66.5% DM, respectively. Feeding brewers' grain dry or wet to dairy cows had no influence on feed intake (25.6 vs. 25.1 kg/d), fat corrected milk yield (40.1 vs. 40.7 kg/d), milk composition and feed consumption. The pH, ammonia, total volatile fatty acids and molar ratios of volatile fatty acids in the rumen fluid were not different between treatments. Fatty acid composition of milk fat from cows fed diets containing dry or wet brewers' grain was identical, except C18:2 and C18:3 fatty acids were lower in milk fat from cows fed wet brewers' grain compared with dried brewers' grain. The results from the present study suggest that the performance of cows fed either dried or wet brewers' grain at 15% of dietary DM was similar when diets had the same DM. The average price for dried and wet brewers' grain in the United States from July 2001 to June 2002 was dollars 145.3 and dollars 96.9/metric tonne DM, respectively. Using wet instead of dried brewers' grain will save dollars 49/metric tonne minus the difference in storage costs. Wet brewers' grain can be fed to dairy cows in areas that are close to the brewery and provides nutritive value similar to the dried brewers' grain.

Results suggest that abrogating the effects of 3MI and BRSV infection may improve the health and growth performance of feedlot cattle. However, in this study, immunity against BRSV did not appear to protect against the potential synergism between 3MI and BRSV infection, possibly because of the slow rates of gain of cattle included in the study or timing of sample collection.