NR 32. Some ruminal digestion characteristics and intake of low quality diets with poultry litter supplementation

Abstract

This Experiment was carried out with fistulated animals at CENIAP in Maracay. Four rumen fistulated cows were used in a Latin square 4x4 with the following treatments, Treatment T0: sorghum stubble hay, Treatment T1: hay plus 1 kg/day supplement, Treatment T2: hay plus a mineral mixture and Treatment T3: hay plus 1 kg/day supplement plus mineral mixture. The animals were housed in individual pens with sorghum stubble hay offered ad libitum. The supplement used was composed of 83.5 % poultry litter, 15% cotton meal and 1.5 % salt. The periods lasted 17 days and intake was measured between days 7 and 14. Rumen liquor samples were taken at 15 day at 07:00, 09:00, 11:00, 13:00, 16:00, 19:00, and 22:00 h and ammonia nitrogen (N-NH3) was analysed. DM disappearance at 48 h (DMD48h) was measured by introducing nylon bags with hay samples during the same day. No differences on DMD48h were observed between treatments, T0, T1,T2 and T3 with values of 34.2, 37.8, 32.8 and 35.4% and large differences were observed for N-NH3 (P<.01) with daily averages of 28.3, 67.8, 24.4 and 65.7 mg/L respectively. Variations in hay and total intake were also observed (P<.05) being in the same treatments with values of 4.9, 5.7, 4.9 and 5.5 kg DM/day and 4.9, 6.5, 4.9 and 6.3 kg DM/day respectively. The results have shown that the supplement based on poultry litter significantly improves the consumption of the base diet associated to an increase in N-NH3 rumen concentration. The absence of responses with mineral supplementation pointed out that the effect of poultry litter in these conditions is related to the supply of N and not to the addition of mineral by this byproduct.