Poultry byproducts and swine liver used in diets for Nile tilapia juveniles

This study aimed at evaluating diets containing protein hydrolysate from poultry byproducts and swine liver (PHPPL), at different inclusion levels, for Nile tilapia (Oreochromis niloticus) juveniles. Seven diets were evaluated, being a negative control (free of both hydrolysate and fishmeal) and positive control (free of hydrolysate but containing fishmeal), besides five diets with 1, 2, 3, 4, or 5% inclusion of the mixed protein hydrolysate. Significant effects were observed regarding the animals' final length, with higher values with the 1% inclusion level than the negative control. The liver's quantitative evaluation revealed that inclusions above 3% might lead to severe alterations in the organ's morphology. The use of PHPPL in the diets that did not contain fishmeal has shown to be effective in maintaining the performance parameters of Nile tilapia. Thus, its use is recommended considering an inclusion level of 3%.

Amino acid digestibility coefficient values of animal protein meals with dietary protease for broiler chickens

A digestibility experiment was conducted to evaluate the effects of dietary exogenous monocomponent protease on the coefficient of apparent total tract digestibility (ATTD) and coefficient apparent ileal digestibility (AID) of amino acids in meat and bones meal (MBM), poultry byproducts meal (PBPM), and feather meal (FM). A total of 512 Cobb-500 male broiler chickens (aged 14 d) were randomly placed into 64 metabolism cages (8 birds per pen) and were allocated to eight treatments with eight replicates in a semi-controlled environmental room. The experimental diets consisted of the basal diet (corn/SBM) and the replacement of 300 g/kg on a weight basis with MBM, PBPM, or FM. The excreta were collected during 3 d (19 to 21 d), and the ileal digesta (using Celite as an indigestible marker) only 1 d (21 d). The protease contained 75,000 PROT units/g. The use of the enzyme increased (P < 0.05) ATTD for alanine, cysteine, glycine, and threonine in the basal diet and AID for the amino acids alanine, cysteine, glycine, lysine, threonine, and valine for the basal diet (vegetable). Regarding meals, there was an increase (P < 0.05) in the amino acid digestibility in large part due to the amino acids of MBM (14) and PBPM (9), with only five amino acids for FM. The amino acids glycine and threonine showed increases (P < 0.05) in both total and ileal digestibility for all animal meals and for the diet based on corn and soybean meal, which indicates a high specificity of the enzyme for these amino acids. The overall results obtained in this study found satisfactory effectiveness of this exogenous protease. The total collection method was lower by 1.83% of amino acids digestibility than the ileal method.

Use of Poultry Byproducts in a Production System for Greenhouse-grown Crops

In 1993, the Arkansas poultry industry produced 1.048 billion broilers with a total live weight of 2.54 million metric tons. Depending on the type of processing used, from 30% to 50% of live weight can end up in the waste stream. Three primary waste-stream products are generated by the poultry industry: feather meal, poultry meal, and bone meal. Feather meal contains ≈14% N, poultry meal 11% N, and bone meal 8% N. Byproduct additions were made to tomato, marigold, and impatiens transplants at the rate of 6, 12, 24 and 48 g/10-cm pot. The two highest rates killed plants outright, while the lower rates resulted in some growth reduction when compared to the control. Studies are under way to further evaluate the use of these byproducts in an organic production system for tomatoes and bedding plants.