Effects of inclustion and exposition times of sugar cane to calcium oxide on the physiologic and digestive parameters of Nellore heifers

Abstract

RESUMO -Objetivou-se avaliar o efeito da inclusão de cal e dos tempos de exposição da cana-de-açúcar à cal sobre o consumo e as digestibilidades total e parcial dos nutrientes e parâmetros ruminais e comparar o dióxido de titânio e o óxido crômico como indicadores para estimar a excreção de matéria seca (MS) fecal e o fluxo abomasal de MS. Utilizaram-se seis fêmeas nelores, com pesos médios de 250 ± 19 kg, fistuladas no rúmen e no abomaso, distribuídas em um quadrado latino incompleto 6 × 6. O experimento foi arranjado em esquema fatorial 3 × 2, com três níveis de cal (0; 0,5 ou 1% da matéria natural) e dois tempos de armazenamento da cana (0 e 3 dias). Não houve efeito dos tempos de armazenamento, nem interação entre os níveis de cal e os tempos de armazenamento, sobre o consumo de nutrientes. Contudo, os níveis de cal aumentaram linearmente os consumos de MS, matéria orgânica (MO) e carboidratos não-fibrosos. Os tempos de armazenamento reduziram a digestibilidade aparente total da MS, MO e fibra em detergente neutro corrigida para cinzas e proteína (FDNcp), mas não influenciaram a digestibilidade aparente ruminal dos nutrientes. A inclusão de cal aumentou o consumo de nutrientes digestíveis totais (NDT), mas não afetou a digestibilidade total e ruminal dos nutrientes. Os indicadores produziram resultados similares para as estimativas de digestibilidade aparente total e ruminal de todos os nutrientes avaliados. Foram observadas interações para o pH ruminal. Contudo, os valores de nitrogênio amoniacal foram influenciados somente pelos tempos de amostragem.A adição de cal não tem efeito sobre a preservação da cana-de-açúcar, mas influencia positivamente o consumo de MS, MO e NDT pelos animais. Os marcadores dióxido de titânio e óxido crômico produzem estimativas de digestibilidades similares.Palavras-chave: cromo, digestibilidade, fistulados, indicadores, titânio Effects of inclustion and exposition times of sugar cane to calcium oxide on the physiologic and digestive parameters of Nellore heifers ABSTRACT -It was aimed to evaluate the effect of inclusion and times of sugar cane exposition to whitewash on intake and total and partial digestibility of nutrients and ruminal parameters and to compare titanium dioxide and chromium oxide as markers to estimate fecal dry matter excretion and dry matter abomasal flow. It was used six rumen and abomasum cannulated Nellore females, with average body weight of 250 ± 19 kg, distributed in an incomplete 6 × 6 latin square design.The experiment was set in a 3 × 2 factorial scheme with three levels of whitewash (0; 0.5 or 1.0% natural matter) and two times of sugar cane storage (0 and 3 days). There was no effect of storage times neither interaction among levels of whitewash and storage times on the intake of nutrients. However, levels of whitewash linearly increased consumption of dry matter (DM), organic matter (OM) and non-fibrous carbohidrates (NFC).Storage times reduced total apparent digestibility of dry matter, organic matter and neutral detergent fiber corrected for as...

Nitrogen metabolism and microbial production of dairy cows fed sugarcane and nitrogen compounds

“…The value found here was higher than found by Morais (2000), 104g MCP/kg TDN, working with Holstein×Zebu cows, fed supplements with increasing levels of urea (0; 1.2; 2.4; 3; 6% based on natural material). Pina et al (2010), compiling several studies using animals for the production of meat and milk subjected to different feeding conditions, recommended a microbial efficiency of 120g/kg TDN as reference to tropical conditions. The highest microbial production is consistent with the highest consumption, which provided greater amount of fermentable substrates and the increased the rate of passage by increasing the drag of rumen microorganisms.…”

Physical-mechanical properties of multinutrient blocks with different binders for goats and sheep intake

“…Binders can interfere with MB properties, such as the digestibility of feed ingredients. Lime, kaolin, Portland cement and bentonite can prevent ruminal acidosis, since these are alkalinizing agents, causing stability of pH in the rumen and increasing nutrient consumption (Pina et al, 2010) and digestibility. Binders such as lime can improve the digestibility of straw and agricultural residues by causing the so-called alkali swelling of cellulose, due to the expansion of cellulose molecules with subsequent breaking of the hydrogen bonds.…”