Scope for High Inclusion of Sorghum DDGS in Broiler Chicken Diets

Xylanase may help to limit the detrimental effect of a high inclusion level of sorghum distillers dried grains with solubles (DDGS), especially in the starter phase of feeding, reported M.R. Barekatain (University of New England) and M. Choct (Australian Poultry CRC) to the 2011 Australian Poultry Science Symposium.

21 June 2011

4 minute read

Distillers' dried grains with solubles (DDGS) are becoming increasingly important in poultry feeding. Research into the use of this material has focused largely on maize DDGS from North America and less work has been done on the predominantly sorghum DDGS that are produced in Australia.

In preliminary tests, the authors investigated the variation in nutrient composition of sorghum DDGS and then conducted a feeding trial on broiler chickens. The trial involved 432 day-old male broiler chicks in a 4 × 2 factorial layout (four levels of DDGS inclusion – 0, 100, 200 or 300g/kg, with or without a xylanase enzyme (Ronozyme WX; DSM), over 21 days on starter diets and subsequently on finisher diets to 35 days of age.

Compared to the control diet, feed intake was significantly increased (P<0.001) with the inclusion of dietary DDGS in the diet during the first three weeks and the entire period of this study.

There was no effect on body weight gain (BWG) from the addition of dietary DDGS or xylanase. Feed conversion ratio (FCR) deteriorated significantly (P<0.05) with the rising level of DDGS in diets during the first three weeks of feeding. Over that period, the effect of xylanase supplementation was not significant at up to 200g/kg DDGS inclusion. However, in birds fed 300g/kg DDGS, the FCR was significantly improved (P<0.05) by the addition of xylanase, over the starter and the entire feeding period of the study, with birds ending up with similar body weight but tending to consume less feed as a result of xylanase addition

Table 1. Growth performance of broiler chickens
Treatments		BWG (g/bird)		Feed intake (g/bird)		FCR
DDGs (g/kg)	Xylanase	1-21	1-35	1-21	1-35	1-21	1-35
0	-	679.5	1843.3	884.8 b	2574.6 c	1.31 cd	1.40 c
	+	698.5	1850.8	894.8 b	2605.3 c	1.30 d	1.41 c
100	-	696.8	1853.9	1020.5 a	2884.7 ab	1.48 ab	1.56 ab
	+	698.2	1858.0	1013.9 a	2836.3 b	1.45 abc	1.53 ab
200	-	682.8	2004.1	1016.7 a	3022.5 ab	1.50 ab	1.51 ab
	+	699.3	1984.2	992.7 a	2947.4 ab	1.42 abcd	1.49 bc
300	-	660.0	1926.0	1017.2 a	3064.9 a	1.54 a	1.59 a
	+	704.3	1925.0	971.6 a	2864.5 ab	1.38 bcd	1.49 bc
	SEM	8.64	16.86	9.27***	25.05***	0.018*	0.01**
Means in a column followed by a different letter differ significantly. (P<0.05, P<0.01, **P<0.001)

While dietary DDGS or enzyme supplementation did not alter digestibility of starch, protein digestibility was adversely influenced (P<0.001) by increasing level of DDGS, which was in line with the results shown by Youssef et al. (2008). Increasing DDGS to 300g/kg in the diet tended to increase ileal digesta viscosity, which was reduced as a result of enzyme addition to the diet. While there was no effect on pancreatic enzyme activities, sucrase and maltase activities were reduced (P<0.001) when birds received 200 and 300g/kg DDGs.

The authors conluded that xylanase may help to limit the detrimental effect of high DDGS inclusion especially in the starter phase of feeding.