Efficacy of New 6-Phytase from spp. on Growth Performance and Nutrient Retention in Broiler Chickens Fed Corn Soybean Meal-based Diets

A total of 420 day-old male Ross chicks were weighed at d 1 of life and assigned to test diets to assess the efficacy of a new Buttiauxella spp. phytase expressed in Trichoderma reesei. Diets were: positive control (PC) adequate in nutrients and negative control (NC) diet (40% and 17% less available phosphorous (P) and calcium (Ca), respectively) supplemented with 6 levels of phytase 0, 250, 500, 750, 1,000, and 2,000 phytase units (FTU)/kg of diet. All diets had titanium dioxide as digestibility marker and each diet was allocated to ten cages (6 birds/cage). Diets were fed for 3 wk to measure growth performance, apparent retention (AR) on d 17 to 21 and bone ash and ileal digestibility (AID) on d 22. Growth performance and nutrient utilization was lower (p<0.05) for NC vs PC birds. Phytase response in NC birds was linear (p<0.05) with 2,000 FTU showing the greatest improvement on body weight gain (20%), feed conversion (7.4%), tibia ash (18%), AR of Ca (38%), AR of P (51%) and apparent metabolizable energy corrected for nitrogen (5.1%) relative to NC. Furthermore, phytase at ≥750 FTU resulted in AID of total AA commensurate to that of PC fed birds and at ≥1,000 FTU improved (p<0.05) AR of P, dry matter, and N beyond that of the lower doses of phytase and PC diet. In conclusion, the result from this study showed that in addition to increased P and Ca utilization, the new Buttiauxella phytase enhanced growth performance and utilization of other nutrients in broiler chickens in a dose-dependent manner

Performance of two 1970s and Ross 308 broiler strains fed drug-free low-protein and recommended-protein diets

SUMMARY The objective of this study was to compare the performance of a modern commercial broiler strain (Ross 308; RS) with that of two 1970s broiler strains (broiler strains 1 and 2) fed a drugfree low-protein or recommended-protein diet. All chicks were vaccinated on d 1 against coccidiosis using the edible immunocox gel vaccine (Vetech Laboratories Inc., Guelph, Ontario, Canada). Six hundred straight-run chicks of each strain were divided into 10 groups of equal weight and randomly placed in 30 floor pens. Five pens of each strain were randomly assigned to the recommended-protein or low-protein dietary regimen. The low-protein grower diet was used as the finishing diet (d 30 to 63). The BW gain (BWG) and FCR of the RS birds were better (P &lt; 0.05) than those of broiler strain 1 birds by 35.6 and 12.2% and those of broiler strain 2 birds by 53.4 and 12.3%, respectively. The BWG and FCR up to 30 d of age were depressed (P &lt; 0.05) regardless of the strain when the low-protein diets were fed to birds. The low-protein diets, however, depressed (P &lt; 0.05) the overall (d 63) BWG of only the RS birds (3,992 vs. 3,771 g/bird). Therefore, the 1970s broiler strains compared with the RS strain had slower growth and performance, but were less sensitive to a decrease in dietary protein. The faster growth rate of the modern RS broiler strain compared with the 1970s strains was due to genetic improvement of the RS strain

Bioavailability of Phosphorus in Two Cultivars of Pea for Broiler Chicks

The aim was to determine the relative bioavailability of phosphorus (P) in peas for 21-day old broiler chickens using slope-ratio assay. One hundred and sixty eight male Ross 308 broiler chicks were divided into 42 groups 4 balanced for body weight and fed 7 diets in a completely randomized design (6 groups/diet) from day 1 to 21 of age. The diets were a corn-soybean meal basal diet, and the corn-soybean meal basal diet to which monosodium phosphate, brown- or yellow-seeded pea was added at the expense of cornstarch to supply 0.5% or 1% total phosphorus. Monosodium phosphate was included as a reference, and hence the estimated bioavailability of P in pea cultivars was relative to that in the monosodium phosphate. Birds and feed were weighed weekly and on d 21 they were killed to obtain tibia. The brown-seeded pea contained 23.4% crude protein, 0.47% P, whereas the yellow-seeded pea contained 24.3% crude protein and 0.38% P. Increasing dietary P supply improved (p<0.05) chick body weight gain and tibia ash and bone density. The estimated relative bioavailability of p values for brown- and yellow-seeded peas obtained using final body weight, average daily gain, tibia ash, and bone mineral density were 31.5% and 36.2%, 35.6% and 37.3%, 23.0% and 5.60%, and 40.3% and 30.3%, respectively. The estimated relative bioavailability of p values for brown- and yellow-seeded peas did not differ within each of the response criteria measured in this study. In conclusion, the relative bioavailability of P in pea did not differ depending on the cultivar (brown- vs yellow-seed). However, the relative bioavailability of P in pea may vary depending on the response criterion used to measure the bioavailability

Nutritional composition, gross energy concentration, and in vitro digestibility of dry matter in 46 sources of bakery meals.

Work was conducted to test the hypothesis that the nutritional composition of bakery meal varies depending on where in the United States the meal is produced due to different raw materials being used in the production of the meals. Forty-six samples of bakery meal were collected from feed mills located in the swine producing states in the United States. Based on the state where samples were collected, they were grouped into 5 regions: 1) AL, DE, GA, NC, PA, and VA (10 samples); 2) CO, MO, OK, and TX (10 samples); 3) IN, KY, OH, and TN (8 samples); 4) IA (11 samples); and 5) MN (7 samples). All samples were analyzed for proximate components, GE, AA, carbohydrates, and minerals, and IVDMD and in vitro energy digestibility (IVGED) were also determined. Results indicated that the average concentration of DM was (91.84 ± 1.29%) and there was no difference among regions. The concentration of ash in bakery meal from MN was greater (P &lt; 0.05) than in meals from other regions, but for all other proximate components, no differences among sources were observed. The average concentration (DM basis) of CP (12.20 ± 2.16%), acid hydrolyzed ether extract (AEE, 9.38 ± 1.95%), starch (44.61 ± 5.47%), and NDF (13.77 ± 4.23%) indicated that bakery meal consists of a mixture of food ingredients originating from flour or whole cereal grains and with some high-fiber ingredients such as brans or canola coproducts also included. It also appears that oil or fats were added during production. With the exception of His, no differences among regions were observed for indispensable AA and the average concentrations (DM basis) of Lys, Met, Thr, and Trp were 0.35 ± 0.08%, 0.19 ± 0.03%, 0.38 ± 0.06%, and 0.13 ± 0.03%, respectively. The bakery meals from MN contained more (P &lt; 0.05) Ca than bakery meals from other regions, indicating that limestone may have been added to bakery meal from MN to improve flowability. However, bakery meals from MN and IA contained less (P &lt; 0.05) total P, phytate, and phytate-bound P than bakery meals produced in the states east of the Mississippi River. There were, however, no differences in IVDMD (79.06 ± 6.62%) or of IVGED (74.84 ± 8.20%) of bakery meals among regions. The present results indicate that variations in the chemical composition of bakery meal obtained from different regions in the United States are relatively small and likely without great impact on the nutritional value of the meals, but in vivo digestibility experiments are needed to confirm this hypothesis