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Matching Livestock Systems with Available Resources |
MEKARN Regional Conference 2007 |
An experiment was conducted on-farm in Muang district, Khon Kaen Province, Thailand. Five crossbred dairy cows (75% Holstein-Friesian), at 100-150 days-in-milk (DIM) and with 450±50 kgBW were used to evaluate the effects of mangosteen (Garcinia mangostana) peel, sunflower oil and coconut oil supplementation on feed intake, nutrient digestibility, ruminal fermentation, milk yield and milk composition. Experimental design was a 5 x 5 Latin square design. Cows were fed rice straw and ruzi grass (Brachiaria ruziziensis) ad libitum. Concentrate was fed based on milk production of 1 kg concentrate to 1.5 kg milk production. Five supplemented treatments were; Control (no supplement) and two levels of mangosteen peel at 100 and 200 gDM/hd/d with (MSP100-SFCO, MSP200-SFCO) or without (MSP100, MSP200) addition of 6% vegetable oils (3% sunflower oil and 3% coconut oil) in the concentrate. Each feeding period lasted for 21 days, during which feed intakes and milk yield were recorded.
Level of mangosteen peel supplementation or supplementation with vegetable oils did not affect nutrient digestibility, blood-urea nitrogen, milk production and milk composition. However, dry matter intake was significantly reduced with supplementation of mangosteen peel with vegetable oil: 3.1, 3.1, 3.0, 2.8 and 2.7 %BW for control, MSP100, MSP200, MSP100-SFCO and MSP200-SFCO, respectively. Ruminal ammonia-nitrogen and acetic acid (C2) concentrations were significantly lower, while propionic acid concentration (C3) was higher in supplemented groups, especially with mangosteen peel supplementation with vegetable oils as compared with the control group. However, supplementation of mangosteen peel with or without vegetable oils in the diet reduced rumen protozoal population significantly (P<0.05) (13.7, 11.9, 12.8, 8.8 and 9.7x105 cell/ml for control, MSP100, MSP200, MSP100-SFCO and MSP200-SFCO, respectively), while rumen bacterial population was significantly increased as compared to the control group. The MSP100-SFO group tended to be higher in milk yield (FCM) and fat content.
Based on this study, a conclusion can be made that supplementation of mangosteen peel at 100 gDM/d with vegetable oils could be beneficial for lactating dairy cows fed a rice straw and ruzi grass (Brachiaria ruziziensis) based diet. The benefits were improved rumen ecology, especially bacterial population, and milk yield and milk composition.