High levels of whole raw soya beans in dairy cow diets: digestibility and animal performance

Abstract

The aim of this study was to evaluate the effects of high levels of whole raw soya beans in the diets of lactating cows. Twelve Holstein dairy cows were used, randomized in three 4 × 4 balanced and contemporary Latin squares and fed the following diets: (i) control (C), without including whole raw soya beans; (ii) 80 g/kg in DM of whole raw soya beans (G80); (iii) 160 g/kg in DM of whole raw soya beans (G160); and (iv) 240 g/kg in DM of whole raw soya beans (G240). There was significant reduction (p < 0.05) in dry matter intake (kg/day) in cows supplemented with G240 compared with C (23.8 vs. 25.3 respectively). G240 diets presented lower crude protein digestibility (g/kg) (p < 0.05) in comparison with C diet (683 vs. 757 respectively). There was significant effect of experimental rations in nitrogen balance (p < 0.05), G240 diet presenting significant reduction in comparison with the other diets, and faecal excretion of nitrogen was higher for G240 diet. The concentration of ruminal ammoniacal nitrogen was significantly higher (p < 0.05) for cows receiving control diet, compared to other diets. G240 diet resulted in significantly lower milk and protein yield (p < 0.05) in comparison with C diet. Significant C18:2 cis fatty acids were observed in milk concentrations (p < 0.05) for G240 diet. The use of high level of whole raw soya beans in dairy cow diets improves the unsaturated fatty acid profile in milk, and the diets (G80 and G160) led to minor alterations in the digestive processes and animal metabolism.

Effect of different dietary inclusion levels of whole raw soyabean on ruminal fermentation and nutrient utilization in Nelore steers

“…Similar results were reported by Barletta et al (2016) who found a decrease in DMI and an increase in EE intakes in comparison to control group in the study on dairy cows fed 240 g · kg −1 of WRS per day. This was explained by the fact that in diets that contained from 50 to 60 g · kg −1 of EE in DM, the addition of seed oil and partially hydrogenated FA reduces intake (NRC, 2001).…”

“…Venturelli et al (2015) included WRS (0, 90, 180 and 270 g · kg −1 diet DM) in the diet of lactating cows and did not find any adverse effect on milk production. The same authors also reported no adverse effect of WRS anti-nutritional factors, such as trypsin inhibitor and urease, on dairy cow health and production (Venturelli et al, 2015;Barletta et al, 2016). In addition, de Almeida et al (2016) fed dairy cows 120 g · kg −1 of WRS and reported a decrease in DMI as the grain was included and an increase in ether extract (EE) intake, with no change in milk production and composition.…”

“…Oven temperature programme started at 70 °C held for 4 min, then increased to 175 °C at a rate of 13 °C · min −1 and was held for 27 min, then increased to 215 °C at a rate of 4 °C · min −1 and was held for 31 min. Hydrogen was used as carrier gas with flux of 40 cm · s −1 as previously described by Barletta et al (2016). During the process of FA identification, four standards were used: standard C4-C24 FAs (Supelco ® TM 37, Bellefonte, PA, USA), vaccenic acid C18:1 trans-11 (V038-1G; Sigma-Aldrich, St. Louis, MO, USA), CLA C18:2 trans-10, cis-12 (UC-61M 100MG, NU-CHEK-PREP ® , Elysian, MN, USA) and CLA C18:2 cis-9, trans-11 (UC-60M 100MG NU-CHEK-PREP ® , Elysian, MN, USA).…”

“…Barletta et al (2016) examined high levels of WRS (240 g · kg −1 diet DM) in the diets of Holstein dairy cows and reported a linear decrease in DM intake (DMI) as WRS was included; however, milk production (3.5% of fat) was not affected. Venturelli et al (2015) included WRS (0, 90, 180 and 270 g · kg −1 diet DM) in the diet of lactating cows and did not find any adverse effect on milk production.…”

“…Currently, Brazil is the second highest soyabean producer in the world with 95 mln t produced in 2014/2015 from total cultivated area of 31.5 mln ha (Agrianual, 2016). The soyabean grain is used as a protein and fat source with its high neutral detergent fibre (NDF) digestibility and approximate composition of 393 g · kg −1 of crude protein (CP), 192 g · kg −1 of fat and 950 g · kg −1 of total digestive nutrients (Valadares Filho et al, 2006;Barletta et al, 2016).…”