# Effect of dietary inclusion of Pennisetum purpureum (Napier) grass on growth performance, rumen fermentation and meat quality of feedlot sussex red steers

## TL;DR

This study found that adding up to 300g/kg of Napier grass to feedlot steers' diets improved meat quality and feed efficiency, but higher levels had negative effects.

## Contribution

The study evaluates the effects of graded levels of Napier grass in diets of Sussex red steers on growth, fermentation, and meat quality.

## Key findings

- Dietary inclusion of 300g/kg Napier grass improved feed efficiency and meat protein and fat content.
- Higher inclusion levels (600g/kg) reduced average daily gain and carcass weights.
- Meat tenderness and moisture were unaffected, but 7-day aged meat thaw loss increased at 600g/kg.

## Abstract

The aim of this study was to evaluate the growth performance, fermentation indices and meat quality of Sussex steers fed totally mixed rations that composed of graded inclusion levels of Napier grass (NP). Three experimental diets designated as diet 1 (0.0 g kg–1 NP: Control), diet 2 (300 g kg–1 NP grass) and diet 3 (600 g kg–1 NP) were formulated. Twenty-four male steers aged 8 months with an average body weight of 185.0 ± 30 kg were used. In a completely randomized design, the animals were allocated to the diets and fed for 120 days. Dietary NP inclusion reduced (P < 0.05) the animals’ average daily gain and increased the feed efficiency. The steers’ daily feed intake and final body weight decreased (P < 0.05) with a 600 g kg–1 inclusion level. The fermentation indices were not affected (P > 0.05) by the inclusion. While the inclusion reduced (P < 0.05) warm muscle temperature, it had no effect (P > 0.05) on carcass dressing percentage, warm and cold initial and ultimate pH. However, 600 g kg–1 inclusion level reduced (P > 0.05) warm and cold carcass weights. Meat physical attributes, moisture characteristics and tenderness were not affected (P > 0.05) by dietary treatments, except for the 7-days aged meat thaw loss, which increased at 600 g kg–1 inclusion level. Inclusion of 300 g kg–1 increased meat protein and fat, but dry and organic matter contents decreased with increasing inclusion levels. Dietary inclusion of NP grass up to 300 g kg–1 in steers’ diets improved feed intake, carcass traits and yielded meat high in protein and fat.