Effect of Replacing Corn Silage with Whole Crop Rice Silage in Total Mixed Ration on Intake, Milk Yield and Its Composition in Holsteins

K S Ki,S H Yang,K S Baek,M A Khan,H J Lee,S B Kim,J G Kim,W S Lee,H S Kim

doi:10.5713/ajas.2009.80556

Abstract

This study was conducted to investigate the effects of replacing whole crop corn silage (WCCS) with whole crop rice silage (WCRS) in the total mixed ration (TMR) on nutrient intake, milk yield and its composition in Holstein cows. The Chucheong rice variety (Oryza sativa L. Japonica) and corn (Pioneer 32 P75) were harvested at yellow-ripe stage and were ensiled in round bales and in trench silos, respectively. Two TMR containing either WCCS or WCRS were prepared. These diets were randomly assigned to 16 midlactating Holstein cows (8 cows per treatment) and were fed for 120 days. The first 20 days were used for dietary adaptation and for the next 100 days daily feed intake, milk yield and its composition were recorded. The pH, lactic acid, NDF, ADF, CP, Ca and P contents were similar in WCRS and WCCS. The DM, ash and EE contents of WCRS were greater compared with WCCS. Nutrient (DM, NDF, TDN and CP) intakes were similar in cows fed WCCS- and WCRS-based TMR. Daily and 4% fat corrected milk yield were not affected by the treatments. Milk composition (percent milk fat, protein, lactose and total solids) was similar in cows fed either WCCS- or WCRSbased TMR. The concentration of milk urea N was greater in cows fed WCRS-based TMR than those fed WCCS-based TMR. In conclusion, round-baled WCRS can replace WCCS in the diet of mid- to late-lactating Holsteins without any deleterious effects on feed consumption, milk yield and its composition. The present findings raise the possibility that WCRS can be used as an alternative roughage source in the diets of dairy cows in countries with surplus rice production.

Highlights

Ensiling is generally practiced to regularize seasonal fodder availability, to preserve forage at a specific nutritive value and to improve the farm land operation/utilization
This study was conducted to examine the effects of replacing whole crop corn silage (WCCS) with whole crop rice silage (WCRS) in total mixed ration (TMR) on feed intake, milk and its composition in mid to late lactating Holstein cows
Similar lactic acid contents and pH were previously reported by others for WCCS (Thomas et al, 2001) and for WCRS (Islam et al, 2004c; Maruyama et al, 2005)

Summary

INTRODUCTION

Ensiling is generally practiced to regularize seasonal fodder availability, to preserve forage at a specific nutritive value and to improve the farm land operation/utilization. The main aim of ensiling is to preserve fodder under anaerobic condition where anaerobic microbes build up organic acids mainly lactic acid by using fermentable carbohydrates (Yahaya et al, 2004). Factors that affect the rate of lactic acid build up, pH decline and final pH of the silage are fermentable carbohydrate in fodder, its buffering capacity (related to the amount of acid needed to change the pH), dry matter (DM) content, the type and amount of bacteria present on fodder (Nisa et al, 2005; Khan et al, 2006). After harvesting the rice crop, the straw is used to feed Korean beef cattle (Hanwoo) and grains are consumed as a major staple food. In recent years the Korea is producing more rice than its domestic needs. This situation demands either to reduce the land under rice cultivation or to find alternative usage of rice crop. Grains and forages for dairy cattle are imported from other

Crude protein Either extract Ash

MATERIALS AND METHODS

Alfalfa hay

Total solids

RESULTS AND DISCUSSION