Effect of phytase dose on productive performance and bone status of layers fed with graded levels of digestible lysine

Título del documento: Effect of phytase dose on productive performance and bone status of layers fed with graded levels of digestible lysine
Revista: Veterinaria México OA
Base de datos: PERIÓDICA
Número de sistema: 000425431
ISSN: 2007-5472
Autors: 1
Institucions: 1Universidad Nacional Autónoma de México, Facultad de Medicina Veterinaria y Zootecnia, Ciudad de México. México
2Universidad Michoacana de San Nicolás de Hidalgo, Facultad de Medicina Veterinaria y Zootecnia, Morelia, Michoacán. México
3AB Vista, Marlborough, Wiltshire. Reino Unido
Període: Jul-Sep
Volum: 5
Número: 3
País: México
Idioma: Inglés
Tipo de documento: Artículo
Enfoque: Aplicado, descriptivo
Resumen en inglés Exogenous phytase could influence dietary protein availability by variation in using dose. The objective of the present study was to determine if incremental dosing of an evolved E.coli 6-phytase would lead to improvements in lysine availability through evaluating performance and bone status in Bovans White layers. A total of 182 layers were placed in individual cages and distributed to 13 treatments: a 3 × 4 factorial arrangement with three levels of digestible lysine (dLys - 0.67, 0.77, and 0.87 %) and four doses of phytase (0, 300, 1 200, and 4 800 FTU/kg) in 0.12 % available P (avP) diets. Additionally, one phytase-free control treatment was included with 0.25 % avP and 0.87 % dLys. Productive parameters were recorded for 25 weeks, from 39 week-old. At the end, abdominal fat deposition and the tibia were sampled; in bone was determined breaking strength and bone ash. Layers fed 1 200 FTU/kg phytase increased egg production percentage (F3,169= 2.01, p = 0.111), abdominal fat deposition (F3,169= 2.52, p = 0.059), bone breaking strength (F3,169= 4.29, p = 0.006) and bone ash weight (F3,169= 3.62, p = 0.014) compared with non-phytase inclusion. Furthermore, 1 200 FTU/kg phytase decreased incidence of broken eggs and soft-shell eggs (F3,169= 2.9, p = 0.036). Phytase and dLys levels influenced egg mass and bone ash concentration (F12,169= 1.86, p = 0.043). FCR and body weight loss was reduced with phytase inclusion (respectively: F12,169= 2.43, p = 0.006, and F12,169= 2.24, p = 0.012). Phytase-free control diet increased egg weight (F12,169= 3.70, p < 0.001), but gave greater BW loss (F12,169= 17.79, p < 0.001), less abdominal fat content (F12,169= 5.85, p < 0.001), and no effect on other variables (p > 0.07). In conclusion, 1 200 FTU/kg of phytase improved productive performance and preserved body weight and bone status, without equivalence of phytase inclusion for dLys level, even with higher doses
Disciplines Medicina veterinaria y zootecnia
Paraules clau: Aves de corral,
Nutrición animal,
Gallinas ponedoras,
Parámetros óseos,
Desempeño productivo
Keyword: Poultry,
Animal nutrition,
Bone parameters,
Laying hens,
Productive performance
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