Non-phytate phosphorous requirements of egg laying pullets from 9 to 12 weeks of age and carryover effects of phosphorous deficiency at 18 weeks of age J.A. Blair, V. Souza Pais, M.E. Persia Journal of Applied Poultry Research, 2025 The non-phytate phosphorous (nPP) requirement of 9 to 12-week-old laying hen pullets was investigated using body weight gain (BWG), mortality corrected feed conversion ratio (FCRm), tibia ash percent (TAP) and tibia ash weight (TAW). The same pullets were transferred back to a standard diet and monitored for longer-term responses to the reduced nPP feeding over 9 to 12 weeks at 18 weeks of age. A total of 672 9-wk-old Hy-Line W36 laying hen pullets were distributed across 42 cages and randomly assigned one of seven dietary treatments (0.13, 0.16, 0.20, 0.23, 0.26, 0.29, and 0.32% nPP, and 0.90% calcium). At 12 wk of age 3 pullets per pen were euthanized for fat-free tibia ash determination. Data were analyzed using ANOVA in JMP Pro 16.0 ( P ≤ 0.05). If significant differences were noted, single-slope broken line regression analysis was completed for BWG, FCRm, TAP and TAW. Only TAW responded to low nPP feeding generating a nPP requirement for 9 to 12 wk old laying hen pullets of 0.18% nPP. Body weight, FCRm and TAP were all unaffected by low nPP feeding. Remaining pullets from the 0.13, 0.16, 0.20 and 0.32% nPP treatments were maintained in their respective cages and phase- fed common corn-soybean meal diets from 12 to 18 wk of age. There were no carryover effects of feeding low phosphorous diets on pullet body weight or tibia ash at 18 wk. These data indicate that the nPP requirement for pullets from 9 to 12 wk of age is lower than current commercial recommendations based directly on TAW and indirectly by a lack of response to BWG, FCRm and TAP and pullets provided adequate nPP diets after a nPP deficiency from 9 to 12 wk were able to recover by 18 wk of age.
Influence of Xylanase Inclusion on Productive Performance, Egg Quality and Intestinal Health of Commercial Laying Hens Fed Energy-Reduced Diets Giovana Longhini, Rasha Qudsieh, Mário Lopes, Isabela Silva, Vitor Pais, Raimundo Netto, Melany Lovon, Carlos Granghelli, Douglas Faria, Lucio Araujo, Cristiane Araujo Animals, 2025 This study evaluated the inclusion of increasing levels of xylanase in reduced-energy diets for commercial laying hens. A total of 280 Lohmann LSL white laying hens were equally allocated one of five dietary treatments, with seven replicates of eight hens each being a positive control: a wheat and soybean meal-based diet (PC, ME 2725 kcal/kg), a negative control diet (NC, PC minus 100 kcal) and three diets with increasing xylanase levels of 50, 100 and 150 g/MT (NC + XM50, NC + XM100 and NC + XM150, respectively). The hens were monitored from 20 to 40 weeks of age to assess productive performance, egg quality and intestinal health, including histomorphometry, permeability and microbiota composition. Xylanase inclusion at 50 and 100 g/MT significantly improved egg production and egg mass, as well as shell strength and thickness, while maintaining feed intake and feed conversion efficiency, while xylanase inclusion at 150 g/MT decreased egg production and egg mass. Additionally, intestinal permeability was significantly reduced, and positive changes were observed in the gut microbiota. Higher doses of xylanase (100 and 150 g/MT) increased bacterial abundance and diversity, with a greater presence of beneficial phyla such as Bacteroidota, which play an important role in gut health. There was also a reduction in Actinobacteriota, indicating a lower presence of potential pathogens. Changes in Campylobacterota, Cyanobacteria and Proteobacteria were observed, especially with the highest xylanase dose. These findings suggest that xylanase can improve laying hen performance and promote intestinal integrity and microbial balance when included in energy-reduced diets, offering a promising strategy to enhance health and productivity in commercial egg production systems.
Effects of feeding spray-dried plasma to broiler breeders and their progeny on broiler performance under stressful rearing conditions of coccidial challenge and heat stress Carlos Alexandre Granghelli, Luís Rangel, Joy Campbell, Javier Polo, Joe Crenshaw, Jessica Moraes Cruvinel, Vinicius Santos Moura, Vitor Souza Pais, Marcelo Oliveira Viviani, Mario Henrique Scapin Lopes, Cristiane Soares da Silva Araujo, Lúcio Francelino Araujo Poultry Science, 2023 A total of 216 Cobb 500 broiler breeder hens were randomly distributed across 2 dietary treatments with 0 or 1% spray-dried plasma (SDP) resulting in 27 replications/treatment and 4 birds/replication. In addition, 36 roosters were divided between the same treatments and housed, in individual pens, being each bird considered a replicate. Experimental diets were fed from 26 wk until 65 wk of age. At 29, 45, and 63 wk of age, broiler breeder hens were inseminated, and eggs were incubated. Three progeny studies were performed and hatched birds were allocated in a randomized 2 × 2 factorial design (maternal diet: with or without inclusion of 1% SDP × progeny diet: with or without the inclusion of 2% SDP from 1 to 7 d of age). After 7 d of age, all birds received the same diet until 42 d. In all trials, birds were challenged with coccidiosis vaccine at 7 d of age. Furthermore, in the second experiment, heat stress was also included for 6 h a day during the whole trial. At 42-days posthatch in the first experiment, greater FI, BW, and BWG in chicks hatched from breeders fed 1% dietary SDP was observed. This effect did not extend to the other hatches. In the second trial, a decreased FCR in broilers fed the control diet from breeder hens fed 1 % of SDP was observed, as well as an interaction between the SDP groups, since broilers supplemented with SDP and originated from breeders fed SDP showed higher BW and BWG in comparison to other groups at 42 d. In the third trial, contrary to what was observed in the first study, SDP supplementation did not affect any of the performance indexes. In the 3 studies, no differences were found in carcass characteristics. SDP did not affect hen BW, egg production, fertility, or hatch of fertile. These results suggest that providing dietary SDP to broilers has some beneficial effects on broiler chickens.
