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generally show greater differences (Box and Ramseur, 1993). Several methods have been used to estimate root Image analysis has greatly simplified the measurement of root length (Rowse and Phillips, 1974;Richards et al., 1979; systems, allowing more detailed and accurate assessment of standard Zoon and Van Tienderen, 1990). The most widely emroot variables. However, maize (Zea mays L.) root morphology has primarily been studied in conventional hybrids. We tested the hypoth-ployed methods are based on the line intersect principle, esis that genotypes carrying the leafy trait (taller plants with more which was first devised by Newman (1966) and later leaves and greater leaf area development) would have root morpholomodified (Marsh, 1971; Tennant, 1975). Because this gies differing from those of conventional maize hybrids. A 3 ϫ 3 method relies on visual counting of grid line-root interfactorial experiment was arranged in a randomized complete block cepts, it can be time consuming and prone to inaccuracy, design with three blocks, three fertilization levels (0, 127.5, and 255 especially when measuring samples with a large proporkg N ha Ϫ1 as NH 4 NO 3 ), and three maize genotypes [leafy reduced tion of fine roots (Smit et al., 1994). However, the line stature (LRS), leafy normal stature (LNS), and a conventional comintercept method improved root measurement and, in mercial hybrid Pioneer 3905 (P3905)]. The genotypes were selected particular, reduced the time required for analysis comfor their contrasting canopy and root architectures. Plants were grown pared with simpler, manual methods. For example, the in 63-L plastic containers, and the roots were measured at the silking stage (80 d from emergence) by scanner-based image analysis. In

Holstein bull calves arriving at five special-fed veal farms (eight production groups) were scored for various physical condition traits and blood-sampled within 2 h after arrival and at 28 d, 84 d, and 1 wk prior to slaughter at 116 to 143 d. Of 1179 total calves in the production groups, 758 calves were scored and evaluated. Blood cell analyses (red and white blood cell counts, hemoglobin, and packed cell volume) were conducted at all four sampling times; total serum protein concentration was obtained at 0 and 28 d. The study was initiated in autumn and ended the following autumn. Mean initial and final body weights were 46.3+/-0.17 and 209.7+/-0.77 kg; mean mortality was 2.5%. Average daily gain of the eight groups ranged from 1.23 to 1.70 kg/d. Subjective scores of 5 = excellent to 1 = very poor condition were used to evaluate 16 different physical condition characteristics. With the exception of leg joint, hoof, and foot scores, most of the physical condition scores exhibited improvement during the first 28 d. Foot and leg impairments did not appear to hinder the ambulatory ability of the calves during the production period. Physical condition scores at d 0 and 28 were generally not related to numbers or types of medical treatments (enteric, respiratory, other, or total) or to average daily gain during the production period. Means for most erythrocytic and leukocytic traits upon arrival (d 0) were within normal ranges, although 27.4% of the calves were clinically or marginally anemic. Final mean hemoglobin and packed cell volume were 8.53 g/dl and 26.1%. Forty-three percent of the calves at d 0 were colostral deficient, assuming that total serum protein concentrations of <5.5 g/dl indicate colostral deficiency. No blood trait was consistently correlated with body weight gain when gain during the production period was divided into quartiles and the blood traits were averaged by gain quartile. Calves in the lowest serum total protein quartile (mean 4.58 g/dl) had more respiratory and total medical treatments than quartiles with higher total protein means. Dairy bull calves arriving at veal production units after transporting from the dairy farm to the auction market (or other collection facility) have several physical impairments. However, most of these physical impairments are improved early in the veal feeding period and are not generally related to subsequent growth rate or medical treatment.

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