Essential oils as modifiers of ruminal fermentation

• Grant number: 12/13932-6
• Support Opportunities: Regular Research Grants
• Start date: January 01, 2013
• End date: December 31, 2014
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Alexandre Vaz Pires
• Grantee: Alexandre Vaz Pires
• Host Institution: Escola Superior de Agricultura Luiz de Queiroz (ESALQ). Universidade de São Paulo (USP). Piracicaba , SP, Brazil
• Associated researchers: Evandro Maia Ferreira ; Ivanete Susin

Abstract

The objective of this project is to define nutritional strategies that are effective to manipulating rumen fermentation and apparent digestibility of nutrients. Will be conducted five experiments, will be evaluated a commercial product (Activo®) (Experiment I) and four essential oils extracted from Brazilian plants with the potential to manipulate rumen fermentation, which follows: Experiment II - essential oils of the fruit of Brazilian peppertree (Schinus terebinthifolíus); Experiment III - essential oils of the sheet of Brazilian peppertree (Schinus terebinthifolíus); Experiment IV - essential oils of East Indian lemongrass (Cymbopogum flexuosus) e Experiment V - essential oils of West Indian lemongrass (Cymbopogum citratus). The experiment I will be conducted in 5 x 5 Latin square design, with five treatments and five periods. The experiments II, III, IV and V will be conducted in a randomized complete block design. The experiment I will consist of five treatments, as follows: 1 (negative control) - base diet (30% roughage and 70% concentrate, % DM) without monensin, 2 (positive control) - base diet added with 25 mg of monensin per kg of diet (as fed basis); treatments 3, 4 and 5 are composed by adding in the diet (% DM) 100, 200 or 300 ppm of Active ®, respectively. Experiments II, III, IV and V also will consist of five treatments, as a negative control and one positive control (the same as in experiment 1) and three volumes of intraruminal infusion of each oil source (3, 6, 9 mL/animal/day). For the experiment I, the trial period will last for 130 days, divided into five sub-periods of 26 days each, of which 7 days will be designed to remove the effects of previous diets ("wash-out" period), 14 for diet adaptation, four days for measurement of DMI, collection of feces and urine, and a day for collection of rumen contents. For the experiments II, III, IV and V, the trial period will last for 23 days each, with 18 days for diet adaptation, four days for measurement of DMI, collection of feces and urine, and a day for collection of rumen contents. The variables analyzed in all experiments are: intake and digestibility of nutrients (DM, OM, CP, EE, NDF, NFC), pH and ruminal concentration of ammonia nitrogen (NH3) and short chain fatty acids (acetate, propionate, isobutyrate, butyrate, isovalerate, and valerate), protozoa counts in ruminal fluid and nitrogen balance. Data from all experiments will be analyzed using the PROC MIXED procedure of SAS (2002). (AU)