Broiler Litter Samples Research Articles

Mineralizable Nitrogen in Broiler Litter: I. Effect of Selected Litter Chemical Characteristics

AbstractBroiler (chicken, Gallus gallus domesticus) litter is a mixture of manure and bedding material that is generated in large amounts by the broiler industry. This litter is typically applied to land as fertilizer, at rates estimated to supply adequate N. Estimation of rates is currently hampered by the lack of rapid methods to determine mineralizable N in BL. This study was conducted to compare the kinetics of N mineralization of 15 BL samples, and to evaluate selected chemical characteristics of the litter as predictors of mineralizable N. Broiler litter samples were mixed with samples of Cowarts soil (150 mg organic N kg−1 soil, −0.02 MPa) and incubated at 25°C for 112 d. Cumulative net N mineralized was fitted to a two‐pool, first‐order model, to determine the size of fast and slow pools of mineralizable N. The fast N pool varied from 116 to 569 g N kg−1 organic N (ON), and could be predicted from uric acid‐N concentration in the litter (R2 = 0.92). The size of the slow N pool did not vary significantly among BL samples; (309 ± 94 g N kg−1 ON). Total mineralizable N (fast + slow N pools) ranged from 465 to 868 g N kg−1 ON, and could be predicted from uric acid‐N and total N concentrations (R2 = 0.91), or from uric acid‐N concentration and C/N of the litter (R2 = 0.95). The simplicity of the chemical indices involved should make this approach attractive to estimate mineralizable N in BL.

Effect of Flock and Floor Type on the Levels of Nutrients and Heavy Metals in Broiler Litter ,

Broiler litter samples were collected from 18 locations over a 3 year period and analyzed for several nutrients and heavy metals. The composition of broiler litter after five flocks of broilers was as follows: moisture, 23.8%; crude protein, 37.4%; ash, 17.8%; calcium, 2.4%; phosphorus, 1.97%; potassium, 2.65%; copper, 319 mg/kg; arsenic, 35 mg/kg; selenium, .29 mg/kg; lead, 3.4 mg/kg; mercury, .31 mg/kg; cadmium, .55 mg/kg. The levels of crude protein and several minerals increased 10 to 15% for each flock from the first to the fifth flocks. The dietary and litter levels of copper were highly correlated (r = +.97). The levels of calcium, phosphorus, and copper in the litter were 2.75 to 3.25 times the dietary levels of these minerals.

Medicinal drug residues in broiler litter and tissues from cattle fed litter.

Broiler litter samples were obtained from several houses in the main broiler producing areas of Virginia and were analyzed for Oxytetracycline, Chlortetracycline, penicillin, neomycin, zinc bacitracin, nicarbazin, amprolium, arsenic and copper. Residues of all drugs were detected with the exception of neomycin and zinc bacitracin. There was considerable variation in the levels of residues detected for all drugs. Longissimus muscle, liver and kidney fat samples were collected from cattle in two trials, in which litter was fed. Chlortetracycline, amprolium, nicarbazin, arsenic and copper assays were conducted on these samples. Low-level Chlortetracycline residues were observed in kidney fat from 3 of 20 animals fed litter, and all other samples were negative. There was a trend for arsenic residues in muscle and liver to increase as the amount of litter fed increased. Copper was shown to accumulate in the liver as a result of feeding broiler litter. No residues of amprolium or nicarbazin were detected. From this study it appears that drug residues are frequently found in broiler littler but feeding litter to cattle resulted in little or no drug accumulation in tissues tested after a 5-day withdrawal of litter.