Whole raw soybean grain in the beef cattle diet in feedlot

Author(s)

Nara Regina Brandão Consolo

• Document type: Master's Dissertation
• Press: Pirassununga.
• Institution: Universidade de São Paulo (USP). Faculdade de Medicina Veterinária e Zootecnia (FMVZ/SBD)
• Defense date: 2011-12-19

Examining board members

Angélica Simone Cravo Pereira; Mário de Beni Arrigoni; Francisco Palma Rennó

• Advisor: Angélica Simone Cravo Pereira

Abstract

The objective of this study was to evaluate the use of whole raw soybean grain in the diet of beef cattle on consumption and digestibility of dry matter and nutrients, ruminal fermentation, growth performance, microbial protein synthesis, carcass traits, meat quality, profile of fatty acids in meat, concentrations of blood parameters, excretion and composition of soybean in the faeces. Two experiments were conducted and in the first one were used 12 Nellore, castrated, cannulated in the rumen, grouped in three 4x4 Latin squares. In the second experiment were used 52 Nellore, not castrated, confined for 84 days in a completely randomized delineation. The diet used was the same for both experiments, consisting of four rations, with the forage / concentrate ratio of 60/40, which was composed of ground corn, soybean meal, whole raw soybean grain, nucleos and corn silage. The diets were: G0: control diet without the inclusion of soybean, G8, G16 and G24, with 8, 16 and 24% respectively of whole raw soybean grain in ration, in the dry matter. In the first experiment, fecal samples and remains were collected on the 11th, 12th and 13th day of experiment, blood and urine samples were collected and the body weight was analyzed. The digestibility was determined by an internal indicator iADF. In Experiment 2, every 28 days, the animals were weighed and blood samples were collected. The animals were slaughtered at 85 days and were weighed the liver (PFi) and hot carcass weight (HCW). Twenty-four hours after the slaughter, the pH was measured, likewise the carcass yield (CY). Deboning was evaluated in rib eye area (REA) and subcutaneous fat thickness (SFT) in the Longissimus muscle. Samples were taken from the Longissimus for determining the fatty acid profile in meat (PAG) in ether extract (EE), objective tenderness and sensorial in aged beef for 14 days. There was a reduction in the dry matter intake, organic matter, total carbohydrates and non-fibrous carbohydrates in animals fed with feed with ration G24. It was observed an increasing linear effect on the EE intake and a quadratic effect on crude protein. Also difference in the apparent digestibility of total carbohydrates and total EE. On ruminal fermentation, there was a linear decline in ruminal pH and ruminal ammonia concentration was higher for animals that received the control diet compared to diets with soybean, with a value greater short-chain fatty acids for the group control. The level of blood cholesterol increased linearly with the addition of grain and in the first experiment there was also increase of HDL cholesterol. For performance, attributes of carcass and measures of ultrasound effect were not observed according to the diet. There was a quadratic effect for shear force (FC), with higher value for the meat of animals that received 8% of the soybean. There was a slight improvement in lipid profile for animals receiving the grain and the inclusion in the sensory analysis of the grain at 24% of diet DM improved the texture of the meat. The use of different levels of whole raw soybean grain in the beef cattle diet changed the intake, digestibility, metabolism and meat quality characteristics. (AU)

• FAPESP's process: 10/03979-0 - Soybeans levels for feedlot I Performance and Blood Parameters. II Carcass and Meat Quality
• Grantee: Nara Regina Brandão Cônsolo
• Support Opportunities: Scholarships in Brazil - Master