ABSTRACT
Foi realizado um estudo sobre qualidade da casca dos ovos incubáveis provenientes de matrizes pesadas com diferentes idades, por meio da avaliação da relação entre peso da casca e peso do ovo e análises de peso específico, espessura, porosidade, resistência e microscopia eletrônica. Os dois tratamentos foram definidos pela idade da matriz, sendo considerados ovos de matrizes novas - 33 semanas - e de matrizes velhas - 63 semanas. Os ovos de matrizes com 33 semanas foram mais leves, e o número de poros por cm² foi menor que o de ovos das aves mais velhas. Ovos de aves com 63 semanas apresentaram menor percentual de casca em relação ao peso do ovo, menor peso específico e menores resistência e espessura da casca. A proporção das membranas da casca em relação à sua espessura total foi maior nas matrizes mais novas. Concluiu-se que ovos de matrizes velhas têm qualidade de casca inferior aos ovos das matrizes novas e que as membranas da casca nos ovos de matrizes novas desempenham papel relevante em sua estrutura.
We conducted a study on eggshell quality from Cobb® broiler breeders at different ages by assessing the relationship between eggshell weight and egg weight and analysis of specific weight, thickness, porosity, strength and electron microscopy. Both treatments were defined by broiler breeder age, considering eggs from young breeders (33 weeks) and eggs from old breeders (63 weeks). It was observed that eggs from breeders at 33 weeks have lower weight and number of pores per cm² compared with eggs from older birds. 63 weeks broiler breeders had lower percentage of eggshell in relation to egg weight, lower specific weight, strength and thickness, when compared with eggs from young breeders. The proportion of shell membranes in relation to its total thickness was significantly higher in young breeders. It was concluded that eggs from older broiler breeders have lower eggshell quality than the young breeders. The shell membranes in young breeder's eggs play a significant role in its structure, making it necessary to focus on this layer in future studies on eggshell quality and their relationship between breeder age and incubation yield.
Subject(s)
Animals , Egg Shell/ultrastructure , Eggs/analysis , Birds/embryology , Tissue Scaffolds/veterinaryABSTRACT
In this study, productive performance, quality of eggs and histological analysis of intestinal villi of the duodenum (length and width) was evaluated in Bovans laying hens of 63 weeks of age, with the addition of butyrate in the diet ( 0, 300, 500 ppm). The results obtained in ten weeks of experimentation showed a response (P < 0.05) on egg production percentaje (86.4, 92.2 and 89.6), egg weight (63.4, 63.4 and 64.1 g), feed consumption/bird/day (111.4, 111.9 and 113.4 g), feed conversion (2.09, 1.95 and 2.03), micro-fractures percentaje (20.8, 14.9 and 12.9), broken eggs percentaje (2.6, 2.1 and 0.6), length of villi (1.15, 1.22 and 1.32 mm) and villi width (0.467, 0.500 and 0.532 mm) to the addition of butyrate. These results indicate the beneficial effect of butyrate in laying hens in the last third of its first production cycle. From information obtained in this study, it is concluded that sodium butyrate on diets at 500 ppm for Bovans laying hens of 63 weeks of age, improves the productive performance, shell quality and intestinal villi integrity.
En el presente estudio se evaluó el comportamiento productivo, calidad del huevo y análisis histológico de vellosidades intestinales de duodeno (largo y ancho) en gallinas de la estirpe Bovans, de 63 semanas de edad, con adición de butirato en la dieta (0, 300, 500 ppm). Los resultados obtenidos en diez semanas de experimentación mostraron respuesta (P < 0.05) en porcentaje de postura (86.4, 92.2 y 89.6), peso del huevo (63.4, 63.4 y 64.1 g) consumo/ave/día (111.4, 111.9 y 113.4 g), conversión alimentaria (2.09, 1.95 y 2.03), de microfracturas (20.8, 14.9 y 12.9), de huevos rotos (2.6, 2.1 y 0.6), longitud de vellosidades (1.15, 1.22 y 1.32 mm) y ancho de vellosidades (0.467, 0.500 y 0.532 mm) a la adición de butirato. Los resultados indican el efecto benéfico del butirato en gallinas ponedoras en el último tercio de su primer ciclo de producción. De la información obtenida en el presente estudio se concluye que el butirato de sodio en dietas a 500 ppm para gallinas Bovans, de 63 semanas de edad, mejora el comportamiento productivo, la calidad del cascarón y la integridad de las vellosidades intestinales.