Influence of Dietary Phytase Inclusion Rates on Yolk Inositol Concentration, Hatchability, Chick Quality, and Early Growth Performance.

The aim of this study was to determine the influence of dietary phytase in breeder hens on yolk nutrients, hatchability, chick quality, and growth rate of their progeny, and their subsequent performance to 42 d post-hatch when fed diets with the same phytase concentrations. Breeder hens (n = 216) were divided into 3 groups receiving nutrient-adequate diets with reduced calcium (Ca) and phosphorus (P) (by 0.16% and 0.15%, respectively), supplemented with either 500, 1500, or 4500 FTU/kg phytase from 27 to 50 weeks of age. Eggs were collected at 38 weeks of age and incubated. On the day of hatch, the chick quality and hatchability were determined, and 18 chicks/group were euthanized for yolk sac collection and the determination of inositol and glycerol concentrations. The remaining chicks were divided into three groups, receiving different diets with reduced Ca and P (by 0.16% and 0.15%, respectively), supplemented with 0, 500, or 1500 FTU/kg phytase to 42 d post-hatch. Increasing the phytase concentration in the breeder hen diet linearly (p < 0.05) increased the number of early embryo deaths and decreased the number of late deaths and pips. The inositol concentration in the yolk sac at day of hatch increased (quadratic; p < 0.05) as the phytase dose increased in the breeder hen diet. The breeder hen diet (p < 0.05) influenced the body weight (BW), feed intake (FI), and feed conversion ratio (FCR) up to 21 days of age. The supplementation of breeder hen diets with 1500 FTU/kg phytase increased the concentration of sodium (Na), magnesium (Mg), potassium (K), manganese (Mn), and zinc (Zn) in the yolk sac. The inclusion of phytase doses up to 4500 FTU/kg appeared to influence embryo mortality, chick feed intake, and BW gain to 21 days and the FCR throughout the entire production phase.

Graded levels of phytase on performance, bone mineralization and carcass traits of broiler fed reduced dicalcium phosphate.

OBJECTIVE: This study was conducted to assess increasing doses of phytase added to broiler diets formulated with different levels of available phosphorus (avP), calcium (Ca), and sodium (Na), and the respective effects on performance parameters, quantitative carcass characteristics, ash and phosphorus deposition in tibia and weight of organs. METHODS: Three different matrices were assumed for phytase with the following nutritional values: matrix A (MT A): 0.165% Ca, 0.150% avP, and 0.035% Na; matrix B (MT B): 0.215% Ca, 0.195% avP, and 0.045% Na; matrix C (MT C): 0.245% Ca, 0.225% avP, and 0.053% Na. There were six different diets: No phytase (formulated to meet the nutritional requirements); phytase 500 FTU/kg+MT A; phytase 1,000 FTU/kg+MT A; phytase 1,500 FTU/kg+MT A; phytase 1,000 FTU/kg+MT B and phytase 1,500 FTU/kg+MT C. RESULTS: There was no significant phytase influence on performance, quantitative carcass characteristics, ash and phosphorus deposition in tibia and weight of the organ throughout the study period, however, it was possible to observe a tendency of improvement in body weight corrected feed conversion for broilers fed the phytase 1,500+MT C diet, where potentially these birds were more efficient on utilize phytic phosphorus and other nutrients bounded to phytate molecule, translating into improvement in performance, and there was also a non significant numerical improvement in body weight corrected feed conversion of broilers fed this diet. CONCLUSION: Broilers fed with diets formulated with different levels of avP, Ca, and Na and increasing doses of phytase have shown no change on performance, quantitative carcass characteristics, ash and phosphorus deposition in tibia and weight of organs.

Aplicação estratégica do balanço eletrolítico em dietas para matrizes pesadas / Strategic application of electrolytic balance in diets for broiler breeders

O objetivo do presente trabalho foi de avaliar o efeito da utilização do conceito de equilíbrio eletrolítico das dietas sobre o desempenho de matrizes de corte. Foram utilizadas 57.000 matrizes pesadas, da linhagem Cobb 500, entre 55 e 62 semanas de idade distribuídas em dois grupos de três galpões que receberam de forma alternada (dois ciclos de quatro semanas) rações que seguiam ou não o conceito de equilíbrio eletrolítico. Foram avaliados o consumo de ração, produtividade, aproveitamento de ovos, mortalidade, produção semanal de ovos/ave e conversão alimentar. O mesmo conceito foi extrapolado para quatro galpões comerciais, de 6.300 aves cada (linhagem Ross), desde a fase de pré-postura, sendo aplicado em dois destes galpões o conceito de equilíbrio eletrolítico. Observou-se, no período de utilização da ração que seguia o conceito de equilíbrio eletrolítico, menor mortalidade (0,285 por cento vs. 0,525 por cento; P<0,05), maior produtividade (56,63 por cento vs. 55,69 por cento; P<0,05) e maior produção semanal de ovos (3,96 vs. 3,88ovos; P<0,05) com melhor conversão alimentar (267 vs. 273g ovo-1; P<0,05). Nos galpões comerciais, foi possível observar diferença na curva de produção, mortalidade e eclosão, resultando em uma produção de 13,87 pintinhos vendáveis a mais no galpão com conceito de equilíbrio eletrolítico. A adoção do conceito de equilíbrio eletrolítico com 180mEq kg-1 para matrizes pesadas melhora a produção de ovos e conversão alimentar e reduz a mortalidade de matrizes de corte.

The aim of this trial was to evaluate the effect of the use of the electrolytic balance concept on broiler breeder's performance. A total of 57.000 Cobb 500 breeders between 55 and 62 weeks of age were used to verify the influence of eletrolitic balance on flock productive parameters . The birds were distributed in two groups of three houses each that received at an alternated way (two cycles of four weeks) feeds formulated with or without the eletrolitic balance concept. It was evaluated feed consumption, productivity, hatched eggs, mortality, egg production/bird and feed conversion. The same concept was used in four commercial houses of 6300 birds each (Ross line), since the pre laying, applied to two of this commercial houses,the concept of electrolyte balance. It was observed during the use of feed that followed the eletrolitic balance concept, lower mortality (0.285 percent vs 0.525 percent; P<0.05), higher productivity (56.63 percent vs 55.69 percent; P<0.05), higher weekly egg production (3.96 vs 3.88eggs; P<0.05) and lower feed conversion (267 vs 273g egg-1; P<0.05). At the commercial houses it was possible to observe a difference in the yield curve mortality and hatching resulting in a higher production of 13.87 more salable eggs in commercial houses with the eletrolitic balance concept. The adoption of the eletrolitic balance concept of 180mEq kg-1 for broiler breeders improve the egg production and feed conversion and reduced mortality of broiler breeders.