Supplemental Dietary Fat from Extruded Soybeans and Calcium Soaps of Fatty Acids for Lactating Dairy Cows

Abstract

Holstein cows (n = 33) were assigned to one of three diets containing soybean meal, supplemental fat from extruded soybeans, or supplemental fat from Ca soaps of fatty acids. Total mixed diets containing (DM basis) 25% corn silage, 25% alfalfa hay, and 50% of the respective concentrate mixtures were fed wk 4 through 15 postpartum. Milk production (29.2, 32.4, and 31.8 kg/d) was higher for cows fed supplemental fat diets. Milk protein percentages (2.99, 2.93, and 2.81) were higher for cows fed the soybean meal diet and were higher with extruded soybeans than with Ca soaps of fatty acids. Milk fat percentages (3.20, 2.69, and 3.47) were higher for cows fed Ca soaps of fatty acids than for cows fed extruded soybeans. Milk fat from cows fed supplemental fat was more unsaturated than from those fed soybean meal and was most unsaturated from cows fed extruded soybeans. Dry matter intakes (17.8, 18.4, and 16.6 kg/d) were not significantly different among diets. Extruded soybeans and Ca soaps of fatty acids were equally effective in increasing milk production, but milk fat content was reduced, and the proportion of unsaturated fatty acids in milk fat was increased, with extruded soybeans.

In situ evaluation of ruminal degradability and intestinal digestibility of extruded soybeans

“…Extrusion (Benchaar and Moncoulon, 1993;Stern et al, 1985) and roasting (Lykos and Varga, 1995) caused a higher flow of total amino acids to the intestine while minimizing the activity of antinutritional factors (Aldrich et al, 1997). Improvements of milk yield in response to heat-treated soybeans were obtained by Schingoethe et al (1996) and Kim et al (1993), but other studies (Driver et al, 1990) did not show any improvement.…”

Utilização de gordura protegida durante o terço inicial da lactação de vacas leiteiras em pastagem de coast-cross

“…Teores médios de proteína bruta (PB) e digestibilidade in vitro da matéria seca (DIVMS) de amostras do pasto de coast-cross-1, durante o período experimental. Kim et al (1993) e National Research Council (2001) também constataram efeitos positivos da adição de gordura protegida na dieta de vacas em lactação sobre a produção de leite. Os efeitos da suplementação energética podem apresentar reflexos a longo prazo, com incrementos na produção de leite pela maior persistência da lactação, como no presente trabalho.…”

“…Não foram detectadas diferenças (P>0,20) entre tratamentos nos teores médios de gordura, sólidos totais e proteína do leite (Tabela 3). Tendência de elevação nos teores de gordura do leite foi constatada por Kim et al (1993), e de redução de 0,1 a 0,15 unidades porcentuais no teor de proteína do leite de vacas que receberam suplementação com lipídeos foi observada por Kim et al (1993) e Palmquist & Jenkins (1980). Essa redução média no teor de proteína do leite também foi detectada no presente experimento; entretanto, o protocolo experimental, e principalmente o número de animais experimentais usados, não possibilitaram estimativa mais precisa do erro experimental, que permitisse definir como efeito da suplementação lipídica as diferenças encontradas nos teores de proteína do leite (0,1%), nos dois períodos experimentais iniciais.…”

Effect of Calcium Soaps on Rumen Fermentation, Protein Degradability of Barley, Rapeseed Meal and Soybean Meal

“…Tamminga et al (1983) suggested that this reduction was associated with the reduced numbers of protozoa, which may decrease lysis of ruminal bacteria and recycling of bacterial protein in the rumen. The decrease in ammonia N in the rumen may indicate a more efficient utilisation of ruminally fermentable carbohydrates for microbial protein synthesis, increased ammonia N utilisation for ruminal microbial synthesis or the inhibition of microbial proteolytic activity (Kim et al, 1993).…”