Prospects of improving efficiency of feed utilisation in broiler

Abstract

This review provides a synopsis of nutritional strategies used to improve the efficiency of feed efficiency (FE) of broilers at a given nutrient density. A small reduction in feed intake can improve FE as a function of improved nutrient digestibility and or post-absorptive metabolism. Restriction of nutrient intake to slow down growth during the mid-growth period followed by reinstatement of conventional feed afterwards, may lead to compensatory growth and improved FE. Replacement of part of the dietary starch with a slowly digested starch source has been shown to help improve growth performance and FE, perhaps by sparing amino acid catabolism by enterocytes, and/or through more synchronised uptake of glucose and nitrogen by the systemic circulation. Development of a larger, more functional gizzard, through provision of feed with coarser particles or structural fibre has been shown to improve digestibility and efficiency of nutrient utilisation. Although broilers are often fed pelleted diets which achieve better growth performance than a mash counterpart, the particulars of the process, including pellet quality, pelleting temperature, and particle size within pellets are important determinants of the magnitude of the pelleting response. Use of the high doses of phytase, often referred to as phytase super-dosing, targeting more complete phytate destruction have been shown to improve FE of broiler fed commercial diets. It can be speculated that combined use of these strategies could potentially help improve FE by between 8 to 10 points (0.08-0.1).

Keywords::

• feed efficiency
• broiler
• compensatory-growth
• rate of starch digestion
• functional gizzard
• phytase super-dosing