Supplementation rate and use of inert fat for lactating dairy cows in tropical grass.

• Grant number: 09/13537-7
• Support Opportunities: Scholarships in Brazil - Master
• Effective date (Start): March 01, 2010
• Effective date (End): August 31, 2011
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Flávio Augusto Portela Santos
• Grantee: Fernanda Lopes Macedo
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil

Abstract

Tropical grasses with a suitable management receiving nitrogen fertilization can have crude protein (CP) varying between 14 and 22% of DM. In this situation, daily milk production can be around 20 kg.day-1, for cows in middle lactation receiving concentrate supplement with no response to inclusion of soybean meal. Commonly, energy is the most limiting factor for cows in lactation in pasture systems.Supplementation rate for cows in pasture systems have been studied with the objective to determine the best relationship between amount of supplement and milk production, with minimal increase in costs.Inclusion of fat sources in supplement for cows with high production potencial in tropical grasses during the summer can be an interesting strategy to improve energy intake. Supplementation with fat sources can increase energy intake without increase and even reducing risks of ruminal disorders caused by excess of non fiber carbohydrate content of major concentrate supplement.The aim of this study is evaluate two supplementation rates for lactating dairy cows in tropical grass (1:2.5 - 1 kg of concentrate for each 2.5 kg milk produced - or 1:5 - 1 kg of concentrate for each 5 kg milk produced) with or without 250 g of inert fat (Megalac - E®) during the summer. The parameter to be evaluated are:1) milk production and milk composition - fat, protein, lactose, casein, milk urea nitrogen and milk fatty acids composition; 2) body weight; 3) dry matter intake - total and pasture; 4) ingestive behavior ; 5) ruminal parameters - pH, VFA, microbial protein production, NH3-N; 6) plasma NEFA and plasma glucose.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

MACEDO, Fernanda Lopes. Levels of concentrate with or without inert fat for lactating dairy cows grazing tropical pastures. 2012. Master's Dissertation - Universidade de São Paulo (USP). Escola Superior de Agricultura Luiz de Queiroz (ESALA/BC) Piracicaba.