A-029 The Clinical Utility of the Trail Making Test- Part B Efficiency Score in a Memory Disorder Clinic

Objective Trail Making Test—Part B (TMTB) is a common neuropsychological instrument measuring aspects of executive functioning such as set shifting and cognitive flexibility. Typically, TMTB is discontinued if not completed within 300 seconds, limiting variability in interpretation for individuals who discontinue. This study aims to alleviate this limitation by examining whether a TMT-B Efficiency (TMT-Be) score can provide useful clinical information in a memory disorder clinic population. Methods TMTB was administered to 167 patients (101 females, 66 males) as part of a neuropsychological evaluation. Diagnostic groups included: Alzheimer’s Disease (AD; N = 83), Mild Cognitive Impairment (MCI; N = 58), and Normal Cognition (N = 26). Ages ranged from 65–94. Participants completed TMTB according to standardized instructions. TMT-Be scores accounted for time, number of errors, and number of incomplete moves. Results TMT-Be scores differed significantly across diagnostic groups (ANOVA, F (2, 164) = 44.81, p < .001). Post-hoc tests using the Bonferroni correction revealed TMT-Be scores in the AD group (M = 17.48, SD = 9.23) were significantly higher than scores of the MCI group (M = 7.91, SD = 5.68) and WNL group (M = 4.65, SD = 1.67). Significant correlations between TMT-Be score and other neuropsychological measures were also found and will be presented and discussed. Conclusion Results support clinical utility of TMT-Be scores for diagnostic purposes, such as differential diagnosis of normal cognition, MCI, and AD. Further research with a larger number of participants and other populations may lend further support to the clinical utility of the TMT-Be scoring method.

Efficiency of the use of ryegrass by heifers in response to the receival of supplement

The intensity and frequency of defoliation of ryegrass (Lolium multiflorum Lam.) by beef heifers exclusively grazing or receiving corn grain or extruded commercial product with fat as supplement were evaluated. The grazing method was put-and-take stocking. The experimental design was completely randomized following a repeated measure arrangement, three treatments and two area replications. The phyllochron of ryegrass was 140.1 and 303.4°GD the leaf lifespan. The intensity (67.0 %) and the frequency of defoliation (6.4 days) were similar, regardless of supply or no of energetic supplement for grazing heifers. The defoliation frequency indicates that the heifers can return about 3.3 times to the same tiller during the leaf lifespan. Considering the different categories of leaf blades, the supply of extruded fat causes the heifers to remove higher proportion (66.5 %) of expanding leaf blades. On ryegrass pasture, the efficiency of forage use is not modified when heifers receive energetic supplement.