Markers for total consumption estimate of penned holstein x zebu heifers

Abstract

It was aimed to evaluate the effectiveness of the internal markers: indigestible fibers (FDAi and FDNi), lignin Klason and the external markers: chromic oxide and modified enriched hidroxiphenilpropan LIPE® on the total intake estimates of penned crossbreed heifers (Holstein x Zebu). They´re assigned to four diets: elephant grass (Pennisetum purpureum Schum.) silage; elephant grass silage and commercial concentrate; chopped sugar cane and urea; chopped sugar cane, urea and commercial concentrate. The chromic oxide underestimated the heifers consumption of all diets and its estimates differed from either hod consumption or those obtained with markers. LIPE® may replace chromic oxide because its consumption estimates did not differ from hod consumption of all diets. The lignin Klason showed to be more appropriate to estimate the heifers consumption that were fed with diets based on grass silage than those heifers fed with sugarcane. This marker underestimated the consumption of heifers that received sugarcane and urea (3,57kg/day of MS) when it was compared to the consumption registered in hod (4,05kg/day of MS), however, for those heifers that received sugarcane, urea and supply, lignin Klason underestimated the consumption (3,90kg/day of MS), so that, it differed form consumption in hod (4,90kg/day of MS). The indigestible fibers (FDAi and FDNi) were suitable to estimate the heifers consumption in all diets. Those results showed that markers present differentiated effect according to the roughage used.