Research Note: Relative bioavailability of zinc in zinc hydroxychloride for chicks.

A chick assay was conducted to determine the effects of Zn source on performance and to establish a Zn relative bioavailability value (RBV) for a new source of Zn hydroxychloride. In the assay, 8-day-old chicks were fed a Zn-deficient soy protein concentrate diet supplemented with 0, 7, and 15 mg Zn/kg from feed grade ZnSO4 monohydrate for 14 d to establish a standard response curve. The same basal diet was supplemented with 3, 7, and 10 mg Zn/kg from a new Zn hydroxychloride (SAMZn). A second source of Zn hydroxychloride (IBZn) was supplemented at 10 mg Zn/kg as a direct comparison to the highest level of SAMZn. Weight gain increased (P < 0.05) with increasing Zn level, regardless of source. Weight gain of chicks fed 7 mg Zn/kg from SAMZn was not different (P > 0.05) from chicks fed 15 mg Zn/kg from ZnSO4. Weight gain was not different (P > 0.05) when comparing the 2 sources of Zn hydroxychloride supplemented at 10 mg Zn/kg. Tibia ash Zn and total tibia Zn were increased (P < 0.05) by all Zn sources and responded linearly (P < 0.05) to Zn supplementation from ZnSO4 and SAMZn. Total tibia Zn concentration was not different (P > 0.05) for chicks fed 10 mg Zn/kg from either source of Zn hydroxychloride. Multiple linear regression of total tibia Zn on supplemental Zn intake (R2 = 0.95) resulted in a RBV of 115% for SAMZn compared with ZnSO4 (set at 100%). The RBV of SAMZn was higher (P < 0.05) than ZnSO4. In conclusion, relative bioavailability of Zn (based on tibia Zn) in Zn hydroxychloride from SAMZn was higher than feed grade ZnSO4 based on multiple regression slope-ratio analysis and was similar to that of IBZn Zn hydroxychloride based on tibia Zn responses to 10 mg/kg supplemental dietary Zn.

Liver disease in anti-hepatitis C virus-positive Norwegian blood donors.

In a prospective study of 16,756 consecutive blood donors, we found 54 donors (0.3%) to be anti-hepatitis C virus (HCV)-positive by a first-generation enzyme-linked immunosorbent assay. After retesting, 18 donors were confirmed positive or indeterminate by a second-generation recombinant immunoblot assay. Sixteen of these donors were found positive by a second-generation enzyme-linked immunosorbent assay, and 15 of these were positive by HCV polymerase chain reaction with two primer sets. Nine donors (50%) had a history of drug abuse. In 15 donors found positive by a second-generation enzyme-linked immunoblot assay liver biopsy specimens were taken after at least 6 months' follow-up. In all except one hepatitis C RNA-negative donor, histologic abnormalities were observed, even when alanine aminotransferase (ALAT) levels were continuously normal or only moderately elevated. The abnormalities were less pronounced in these donors (n = 5) than in donors with ALAT levels increased more than twice the upper normal limit (p < 0.05). In conclusion, we found the proportion of previous drug abusers in anti-HCV-positive blood donors to be high. We confirm that the presence of anti-HCV (second generation) usually, and HCV-RNA always, seems to indicate ongoing infection--also when ALAT levels are normal. Our study further suggests that low-activity hepatitis, evaluated by ALAT levels, may indicate a milder disease.

[Cholesterol status of blood donors. Motivation for dietary changes and their effects]. / Kolesterolstatus hos blodgivere. Motivasjon for kostendringer og effekt av slike endringer.

We present the results of serum-cholesterol measurements in 956 blood donors and an evaluation of their motivation for dietary changes based on answers to a questionnaire. The mean serum-cholesterol level was 5.5 mmol/l for women and 5.7 mmol/l for men, with an increase in serum-cholesterol with age. Motivation for dietary changes was food, since 85% answered that they would change their diet if their serum-cholesterol was high. 65% of those who knew their serum-cholesterol to be high before this study had changed their diet. 38% of the smokers answered that they would stop smoking if their serum-cholesterol was high. Eight to 14 months later, serum-cholesterol measurements in 201 of the blood donors showed that 72.4% of those with serum-cholesterol greater than 6 mmol/l had changed their diet and that these had reduced their serum-cholesterol by an average 10.6%.