Evaluating internal and external markers versus fecal sampling procedure interactions when estimating intake in dairy cows consuming a corn silage-based diet.

Feed intake assessment is a valuable tool for herd management decisions. The use of markers, either internal or external, is currently the most used technique for estimating feed intake in production animals. The experiment used 10 multiparous Holstein cows fed a corn silage-based diet, with 55:45 forage-to-concentrate ratio, the average fecal recovery (FR) of TiO2 was higher than FR of Cr2O3, and both FR were more than unity. With internal markers, acetyl bromide lignin and cutin FR were lower than unity, and average FR for indigestible neutral detergent fiber (iNDF) and indigestible acid detergent fiber (iADF) was 1.5. The FR was unaffected by the fecal sampling procedure and appears to be an intrinsic property of each molecule and how it interacts with digesta. Of the 2 external markers, only Cr2O3 produced accurate fecal output (FO) estimates and the same happened to dry matter digestibility (DMD) when iNDF and iADF were used. Estimates for DMD and FO were affected by sampling procedure; 72-h bulk [sub-sample from total feces collection (TFC)] sampling consistently produced accurate results. The grab (sub-samples taken at specific times during the day) sampling procedures were accurate when using either of the indigestible fibers (iNDF or iADF) to estimate DMD. However, grab sampling procedures can only be recommended when concomitant TFC is performed on at least one animal per treatment to determine FR. Under these conditions, Cr2O3 is a suitable marker for estimating FO, and iNDF and iADF are adequate for estimating DMD. Moreover, the Cr2O3+iADF marker pair produces accurate dry matter intake estimates and deserves further attention in ruminant nutrition studies. The method of dosing the external markers is extremely important and greatly affects and determines results. Whichever the method, it must allow the animals to display normal feeding behavior and not affect performance. The grab sampling procedures can replace TFC (once FR is established), which may open new possibilities for pasture-based or collectively housed animals.

Fucosidosis in a native-born Briton.

This investigation reports the biochemical findings in a native-born Briton suffering from the adult form of fucosidosis. Alpha-L-fucosidase, alpha-L-iduronidase, and beta-D-galactosidase were studied in cultured fibroblast and leucocytes from the patient with fucosidosis, her maternal grandfather, and several normal controls. A complete lack of alpha-L-fucosidase activity was found in the patient's fibroblasts and leucocytes while the grandfather exhibited a heterozygous level of alpha-L-fucosidase activity in his leucocytes. Excessive excretion of what is very likely to be a fucose-containing sphingolipid was demonstrated in the patient's urine by thin-layer chromatography. Compared with five isoenzyme forms of alpha-L-fucosidase activity in normal leucocytes, cellulose acetate electrophoresis of the patient's leucocytes produced evidence of a single band of slight activity associated with one of the isoenzymes. This residual activity probably accounts for the survival of such patients into adolescence and beyond.