The Effects of Dietary Methionine and Protein Levels on Growth Performance and Carcass Characteristics of Broiler Chickens

Document Type : Scientific - Research Articles

Authors

Yahya Mohammadi ¹

Jalal Yousfi ²

Hassan Darmani-kuhi ¹

¹ Elam university

² Elam eslamic Azad university

10.22067/ijasr.v1i2.1942

Abstract

This study was aimed to determine the effects of different dietary levels of methionine and protein on the growth
performance and carcass characteristics of broiler chickens. A total of 240 broiler chicks were distributed into a completely
randomized design with a 2 × 3 factorial arrangement. Experimental factors were: two levels of protein (20% or 24% for
starter and 18% or 22% for grower), and three levels of methionine (standard, 115% standard and 130% standard). The
experiment consisted of 6 treatments with four replicates and 10 birds in each replicate. All diets were calculated to be
isocaloric for starter (7 to 21 d) and grower (22 to 42 d) periods. Birds had free access to feed and water throughout the
experimental period. Mean body weight (BW) and feed intake were determined at the end of each period. On days 43 two
birds were randomly selected from each pen and individually weighed and slaughtered. Then, carcass weight and weight of
parts (yield of breast and abdominal fat pat) were determined. The results indicated that excessive levels of methionine and
dietary protein improved weight gain and feed conversion ratio (FCR) at starter, grower and total periods. Feed intake was
not affect by the increase in dietary methionine and protein levels. The increase in dietary methionine and protein levels was
affective in increasing breast meat yield and decreasing abdominal fat pad. There were no interactions between methionine
and protein for BW, FCR or carcass characteristics.

Keywords

Methionine

Protein

Performance Growth

Carcass Characteristics

Broiler Chickens

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References

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