Digestibility and N retention by goats fed graded levels of cassava (Manihot esculenta Crantz) foliage

 Tran Thi Thu Hong

  Tranthuhong@hotmail.com 

  Abstract

 A 3x3 Latin square design was employed to evaluate the substitution of wheat bran by graded levels  (50, 75 and 100%) on dry matter basis, of chopped cassava foliage (Manihot esculenta Crantz) in diets for Bach Thao growing male goats (average weight 15 kg) by determining total tract digestibility indices and N retention. Chemical characteristics of cassava foliage and wheat bran were: crude protein (Nx6.25) 28.4 and 18.4; NDF 48.8 and 35.7% in dry basis respectively.

 Average daily feed intake was 31.2 g DM/kg live weight and was not significantly different (P>0.10) between diets.The animals gained weight during the trial and showed no symptoms of intoxication even when fed high levels of cassava foliage.

 Nutrient digestibility was not significantly (P>0.05) reduced with increasing cell wall level in the diet. Average DM, N and NDF digestibility were 77.9, 85.1 and 73.0% respectively. There was no treatment effect (P>0.05) on N retention (12.6, 11.2 and 8.4 g/day for 50, 75 and 100% of cassava foliage in the diet respectively).

 There were no treatment influence in rumen pH and NH₃ values (on average 7.27 and 762 mg/L).

 According to the present experiment, cassava foliage protein can use it as good protein source for growing goat in integrated farming systems.

 Key words: cassava foliage, Manihot esculenta, digestibility, nitrogen, goats