The effects of physically effective neutral detergent fibre content on growth performance and digestibility in beef cattle fed with total mixed ration

Abstract

The objective of this study was to investigate the effects of physically effective neutral detergent fibre (peNDF) content on growth performance and digestibility in beef cattle fed with total mix ration (TMR). A total of 54 six-month-old male Holstein beef cattle (averaged weight of 280 kg) were divided into 3 groups each consisting of 18 cattle. Feed ingredients were added to the TMR wagon as follows; wheat straw, alfalfa hay, barley, corn, cotton seed meal, conventional beef feeding, corn silage, beet pulp, molasses and feed additives. TMR was offered daily to animals. The dietary treatments included; a) TMR diet mixed for 7 min (T1); b) TMR diet mixed for 14 min (T2), and c) free choice diet (FCD). The same ingredients feeds of TMR was given to the T1 and T2 groups but in different mixed times. Alfalfa hay and calf grower feed were separately offered animals in FCD. End of first month of trial, the daily feed intake (DFI) and dry matter intake (DMI) were significantly lower in the cattle that received FCD. At the end of the second month, the daily feed intake and dry matter intake were the highest in T1 diets among all the groups. There was no significant effect of different mixing times on n 48-h NDF digestibility (NDFD48) and ADF (ADFD48) digestibility of TMR. The lowest ration cost of 1 kg daily gain was observed for T2 and the daily feed intake cost was lower for FCD group than T1 and T2. It was concluded that mixing time had an effect on dry matter intake (DMI), average daily gain (ADG).

Keywords

• feedlot cattle
• in vitro digestibility
• particle size
• pendf
• total mix ration