Wide Spectrum of Nutrition Research Presented at International Science Forum
Nutrition was the main theme in five sessions at the International Poultry Scientific Forum in Atlanta, USA, in January 2011. Jackie Linden, senior editor of ThePoultrySite, has summarised a selection of the papers to give a flavour of the variety of research work presented at the meeting.
6 April 2011
3 minute read
Broiler Gut Microflora and the Role of Nutrition
| * "Age and stocking density were the factors that most affected the gastrointestinal mucosal bacterial communities" |
Environmental and nutritional challenges can significantly affect broiler performance and economics of poultry meat production. Possible negative changes in gut microflora associated with these challenges may accentuate further performance responses observed in broilers today, according to E. Pierson of Danisco Animal Nutrition presenting a paper on behalf of Professor E.T. Moran of Auburn University4.
The results of the work revealed that age and stocking density were the factors that most affected the gastrointestinal mucosal bacterial communities, with the low-density negative control having a similar profile of microflora to the birds kept at high stocking density. A greater number of species of of intestinal microflora is associated with better health and performance, according to the researchers.
A combination of Avizyme 1502 containing (minimum per kg diet) of α-amylase (300u), xylanase (400u) and protease (4000u) and Phyzyme XP TPT (500 FTU phytase) were supplemented at two levels to corn-soy based formulations in male Ross 708 (Aviagen) broilers reared to 42 days of age at two densities (15 and 30 birds; 4.18 square metres). Essential nutrient requirements (NRC) were assured with the positive control (PC) formulations.
Enzyme and bird density treatments were also compared when metabolisable energy (ME), available phosphorus and calcium were reduced in negative control diets (NC). All chicks received Coccivac-D (Schering-Plough) in lieu of a coccidiostat before placement on used litter; no antimicrobials were employed.
At 42 days of age, higher bird density resulted in significantly lower gain (up to 6.2 per cent), lower feed consumption (up to 7.7 per cent) and higher mortality (up to three-times). At this age, NC birds had significantly lower body weight gain and greater mortality than PC.
Supplementing NC diets with the combination of enzyme products increased body weight and provided relief from mortality to levels similar with the PC. A difference in live performance was not apparent when enzyme supplementation was decreased in half.
Gastrointestinal tracts were sampled on days 1 and 42 for microbial community assay. Age and stocking density strongly influenced the gastrointestinal mucosal bacterial communities. Some treatment differences in these variables were also observed at each stocking density, say the researchers.
