Nutritive value of dry citrus pulp and its effect on performance in geese from 35 to 70 days of age

Abstract

The study was conducted to determine the chemical composition nutritive value of dried citrus pulp (DCP) and its effect as a feed supplement on the performance of geese. The results of Experiment 1 showed that the DM, GE, CP, EE, CF, NDF, ADF, calcium, and total phosphorous of DCP were 90.75%, 3.60 Mcal/kg, 6.17, 3.51, 15.69, 23.37, 21.49, 3.60, and 0.13%, respectively. The content of methionine, lysine, valine, leucine, isoleucine, threonine, phenylalanine, arginine, histidine, glycine, proline, serine, cystine, alanine, glutamate, tyrosine and aspartate, and tryptophan was 0.02, 0.22, 0.24, 0.33, 0.18, 0.20, 0.22, 0.19, 0.10, 0.25, 0.51, 0.21, 0.02, 0.28, 0.54, 0.15, 0.46, and 0.05%, respectively. In Experiment 2, the digestibility of energy and amino acids of DCP were analyzed using an emptying followed by force-feeding method. The AME of DCP was 2.05 Mcal/kg, and the true total tract digestible methionine, lysine, valine, leucine, isoleucine, threonine, phenylalanine, arginine, histidine, glycine, proline, serine, cystine, alanine, glutamate, tyrosine and aspartate, and tryptophan contained in DCP by geese were 0.01, 0.10, 0.12, 0.19, 0.09, 0.12, 0.14, 0.13, 0.06, 0.14%, 0.42, 0.13, 0.01, 0.15, 0.31, 0.08, 0.28, and 0.03%, respectively. In Experiment 3, 210 35-day-old male Sichuan white geese were randomly allocated to 5 treatments, and each treatment group was fed one of 5 experimental diets containing 0, 4, 8, 12, or 16% DCP until 70 d of age. Geese that were fed diets containing 4% DCP exhibited greater ADG compared to the other 4 groups. Geese fed diets supplemented with 16% DCP had increased ADFI (P < 0.05) and a higher FCR (P < 0.05) than those fed the diet containing zero to 12% DCP. Moreover, inclusion of DCP in the diet did not affect the yields of breast meat, leg meat, subcutaneous fat and skin, and abdominal fat across the 5 treatment groups. In conclusion, DCP appears to be a potential feedstuff for geese, and DCP can be included in diets below 12% without negative effects on growth performance and carcass yield in geese.