Feeding value of high and low tannin sorghum as broiler feed

An experiment was carried out to examine the effect of replacement of maize with three verities of sorghum (i.e., red, yellow and white) varying in tannin content on growth performance and nutrient utilization in broilers. The birds were fed on reference and nine test diets in which the maize moiety of reference diet was replaced at graded level of 50, 75 and 100% on equal energy content basis with each variety of sorghum. A metabolic trial at 5^th week of age was conducted on experimental broilers involving all the dietary treatments in order to assess the retention of energy, nitrogen, calcium and phosphorus. Cumulative feed intake (g/b) during 0–6 wk was significantly (P<0.01) higher in birds fed on reference diet and lower in those received 100 percent yellow sorghum diet. Body weight gain (BWG) between 0–6 wk was found higher (P<0.05) in the birds fed on reference diet when compared to red sorghum fed group as well as 100 percent yellow and white sorghum diets. Feed conversion ratio (FCR) during 0–6 wk, was found better (P<0.01) in birds fed on reference and 50 percent yellow sorghum diets as compared to red sorghum fed diets. The energy metabolisability (%) was significantly (P<0.01) higher on 50% yellow sorghum diet and lower on both 75 and 100% red sorghum diets as compared to those on other diets. Per cent nitrogen retention was significantly (P<0.01) higher in 50% yellow sorghum diet than in 50% white, 75% yellow and 100% red sorghum dietary groups. Ca retention (%) was significantly (P<0.01) higher in birds fed on reference diet than those fed on sorghum based diets. In all the 3 varieties of sorghum, the Ca and P retention was decreased as the level of sorghum increased in the diet. The P retention (%) was highest in birds fed on reference diet and lowest on 100% red sorghum diet. It was concluded that incorporation of high tannin containing red sorghum (tannin content 1.84%) in broiler diet at higher proportions should be limited. But relatively low tannin containing yellow and white sorghum (tannin content 0.57% and 0.32%, respectively) can be incorporated in broiler diets up to 75% of maize.