Effects of supplemental dietary phytase & 25-hydroxycholecalciferol on excreta characteristics and nutrient content from commercial layers inoculated before or at the onset of lay with the F-strain of Mycoplasms gallisepticum

Authors: Miles, Dana; Branton, Scott; PEEBLES, DAVID - Mississippi State University; BURNHAM, MATTHEW - Jones County Jr College; Brooks, John; Moore, Philip

Submitted to: International Journal of Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 5/6/2021
Publication Date: 7/31/2021
Citation: Miles, D.M., Branton, S.L., Peebles, D.E., Burnham, M.R., Brooks, J.P., Moore Jr, P.A. 2021. Effects of supplemental dietary phytase & 25-hydroxycholecalciferol on excreta characteristics and nutrient content from commercial layers inoculated before or at the onset of lay with the F-strain of Mycoplasms gallisepticum. International Journal of Poultry Science. 20:209-214. https://doi.org/10.3923/ijps.2021.209.214.
DOI: https://doi.org/10.3923/ijps.2021.209.214

Interpretive Summary: To maintain sustainable commercial egg production, innovative dietary inputs, their interaction with disease control agents, and effects on all aspects of the production system and bird health must be investigated. Previous studies determined that a supplemented diet affected hen body weight, reproductive organs, and the digestive system, but did not affect layer performance or interact with the effects of F-strain Mycoplasma gallisepticum (FMG) inoculation. However, the effect on excreta nutrient content were unknown. This study compared basal vs. supplemented diets (phytase and vitamin D), type of inoculation (FMG vs. sham), and age of inoculation (prelay or at lay) for commercial layer chickens. Of the studied parameters, only hen age affected fecal moisture, total N, total C, K and Zn. Fecal moisture content decreased (83 to 79%) while total N, total C, K, and Zn generally increased with hen age. Integrators need not be concerned that the phytase and vitamin D supplemented diet will incur manure handling changes relative to nutrient or mineral content. The characterization and mineral analysis provide a data resource for layer excreta as hens age. Further, implications of layer manure versus broiler litter differences may be important to national waste inventories.

Technical Abstract: To maintain sustainable commercial egg production, innovative dietary inputs, their interaction with disease control agents, and effects on all aspects of the production system and bird health must be investigated. Whereas, in companion studies, the supplemented diet has been shown to decrease blood hematocrit, decrease hen body weight (in sham-inoculated control birds), influence reproductive organ and digestive system characteristics; it has not been shown to affect layer performance or interact with the effects of F-strain Mycoplasma gallisepticum (FMG) inoculation. However, the effect on excreta nutrient content were unknown. Commercial layer diets were supplemented with phytase and 25-hydroxycholecalciferol to determine the effects on the characteristics and nutrient content of excreta from 39 to 55 weeks of age for hens that were inoculated (or sham inoculated) with FMG at 12 weeks (prelay) or at 22 weeks (onset of laying cycle). Basal vs. supplemented diets, type of inoculation (FMG vs. sham), and age of inoculation were compared. In two trials, layer excreta were collected at 39, 43, 47, 51, and 55 wk of age where moisture content, pH, N, C, Ca, K, Mg, Na, P, Cu, Fe, Mn and Zn concentrations were determined. Diet, inoculation age nor inoculation type had an effect on fecal moisture, pH, total N, or total C. The results show that fecal moisture content decreased (83 to 79%) while total N (35.8 to 54.6 g/kg), total C (317 to 339 g/kg), K (22.8 to 27.1 mg/kg), and Zn (552 to 794 mg/kg) generally increased with hen age. Of the studied parameters, only hen age affected these excreta characteristics such that integrators need not be concerned that these dietary changes will incur manure handling changes relative to nutrient or mineral content. The characterization and mineral analysis provide a data resource for layer excreta as hens age. Further, implications of layer manure versus broiler litter differences may be important to national inventories.