Bioavailability of different Zinc sources for rabbits

One hundred and forty 60-day-old New Zealand White and California rabbits of both sexes were used to determine bioavailability of different inorganic zinc sources, zinc oxide (ZO), zinc sulfate (ZS), and zinc carbonate (ZC), and an inorganic zinc source, zinc quelate (ZQ) in the concentrations of 0, 50, 100, 150 and 200 ppm. The standard curve was also determined. Consumption was higher for 50ZO and 100ZO diets, and lower for 200ZO, 100ZS, 200ZS and 200ZQ (R²= 0.18). Higher weight gains were observed for animals fed on 50ZO, 100ZC, 200ZC, 100ZS, 200ZS, 100ZQ and 200ZQ diets and lower for animals fed on 0ZO and 100ZO diets (R²= 0.23) Higher feed: weight gain ratios were observed for animals fed on 0ZO, 100ZO, 150ZO and 150ZS, and lower for rabbits fed on 200ZS, 200ZQ, 200ZC, 100ZQ and 100ZS diets (R²= 0.26). Rabbits fed on 100ZO, 150ZO and 150ZS diets showed the highest zinc concentrations, and 100ZC and 200ZC diets the lowest concentrations. No differences between sexes were observed but New Zealand White rabbits presented the highest zinc deposition. The equation to predict zinc concentration in the liver (<IMG SRC="/img/fbpe/abmvz/v54n6/a13img01.gif">) based on basal diet zinc consumption (x1), and zinc oxide (x2), zinc sulfate (x3) zinc carbonate (x4) and zinc quelate consumptions (x5) was estimated as <IMG SRC="/img/fbpe/abmvz/v54n6/a13img01.gif" > or = 1.11 + 0.66 x1 + 0.55 x2 0.57 x3 + 0.56 x4 + 0.56 x5 (R²= 0.59).

Rabbit; bioavailability; zinc; organic sources; inorganic source

Universidade Federal de Minas Gerais, Escola de Veterinária Caixa Postal 567, 30123-970 Belo Horizonte MG - Brazil, Tel.: (55 31) 3409-2041, Tel.: (55 31) 3409-2042 - Belo Horizonte - MG - Brazil