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Fifty-two Angus x Gelbvieh rotationally crossed virgin, ovariectomized, or single-calf heifers were slaughtered after 100 d on a high-concentrate diet. Heifers from each treatment were approximately 31, 33, or 35 mo of age, and they produced 31 A, 5 B, and 16 C maturity carcasses. Because of the small number, B maturity carcasses were not included in this study. Number of A maturity carcasses decreased as age increased. No differences (P > .05) in slaughter weight, total weight gain, dressing percentage, longissimus muscle area, or kidney fat percentage existed between carcass maturity groups, but C maturity heifers had 3.56 mm more fat (P < .01) over the longissimus muscle than A maturity heifers. Marbling scores of slight79 and small0 for A and C maturity carcasses, respectively, did not differ (P > .05). The A and C maturity heifers had similar amounts of collagen and hydroxylysyl-pyridinium crosslinks in metacarpal bone cortex and in longissimus muscle. Neither means for panel tenderness nor Warner-Bratzler shear values differed (P > .05) between maturity groups. Coefficients of variation for tenderness were slightly higher in steaks from C maturity carcasses, but CV for shear values between A and C maturity groups were similar. Because inconsistent meat tenderness is a recognized problem in the beef industry, more research on tenderness variability within maturity and marbling groups is needed. This information, in addition to pooled SEM and differences between means, should aid in finding ways to reduce beef tenderness variability.

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Epididymal glycosidases play a role in sperm maturation by modifying sperm surface glycoproteins. To study the effects of ethanol on epididymal sperm maturation, ethanol (3 g/kg body weight as 25%, v/v) was administered to a group of rats by gastric-intubation twice daily for 30 days. In another group, rats were also treated with alcohol for 30 days but were then withdrawn from treatment for 30 days to assess the reversibility of ethanol-induced effects. Ethanol-induced changes in epididymal tissue and sperm glycosidases, cauda epididymal sperm motility and the fertility of rats were assessed. Ethanol treatment caused a marked decrease in the specific activities of glycosidases in both tissues and spermatozoa from epididymal segments. Cauda epididymal sperm motility and the fertility of ethanol-treated rats were significantly impaired compared to control rats fed an isocaloric diet. These changes are likely to be the consequence of direct and indirect effects of ethanol mediated through subnormal testosterone and dihydrotestosterone. Most of these changes were found to be reversible. The present study suggests that impaired activity of sperm glycosidases may be one of the factors responsible for defective sperm motility and fertilizing potential in ethanol-treated rats.