Effect of substitution of urea with different types and levels of ruminant manure on microbial evaluation of rice straw silage

Abstract

This study was conducted in Nutrition Lab. Department of Animal Production, College of Agriculture, Al-Qasim Green University to investigate the effect of type and level of substitution of urea with ruminant manure (sheep, cow and buffalo) on basis of nitrogen content on microbial composition of rice straw silage. Urea was substituted with dried manure at six combinations, 100:0, 90:10, 80:20, 70:30, 60:40 and 50:50. Silage samples were prepared by treating chopped straw with pre-treated solution contained 10% low quality juice and 2% urea. Treated straw was packed in double plastic bags which were closed tightly and fermented for 60 days in bits. Results revealed that samples prepared by addition of cow manure were characterized with higher number of total anaerobic (P˂0.05) and lactic acid bacteria (P˂0.01), 9.22 and 8.62 log CFU.g-1 FM respectively. Whereas, lower (P˂0.01) number of molds and yeasts were detected in those prepared with addition of buffalo manure, 3.51 and 4.54 log CFU.g-1 FM respectively. Significant increases were also observed in the total number of anaerobic bacteria and lactic acid bacteria with lower (P˂0.01) numbers of total aerobic bacteria due to substitution of urea with manure, however, lower (P˂0.01) number of molds and yeasts, 3.49 and 4.51 log CFU.g-1 FM were detected in samples prepared with a combination of 100:0 of urea: manure.