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1.
J Therm Biol ; 94: 102773, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33292973

RESUMEN

This study had the following objectives: (i) to evaluate the thermoregulatory and behavioral responses of light laying hens supplemented with different types and dosages of phytases in the two day shifts; and (ii) to integrate the thermoregulatory and behavioral responses with performance of these birds raised in a hot environment. 270 light laying hens of the Hy-Line White lineage, with a body weight of 1.60 ± 0.092 kg were distributed in a completely randomized design in a 2 × 2 + 1 factorial model with two types of phytases (bacterial and fungal) and two dosages (450 and 900 FTU), and a control diet. The day shift (morning and afternoon) was considered as a fixed effect in the factorial arrangement. Principal component analysis (PCA), correspondence analysis (CA) and canonical discriminant analysis (CDA) were used. There was no interaction (P > 0.05) between phytases and dosages for thermoregulatory responses. Respiratory rate (RR), cloacal temperature (CT), and surface temperature with feathers (STWF) and featherless (STF) were higher (P < 0.001) in the afternoon. Birds show different thermoregulatory and behavioral responses in the two shifts of the day. We also observed that birds supplemented with bacterial and fungal phytase showed similar thermoregulatory and behavioral responses to the control group in both day shifts. Expression of the "eating" activity was greater in the morning, while the birds remained sitting longer in the afternoon. Egg production was higher (P < 0.001) in birds supplemented with bacterial phytase. The phytase dosages had no effect on thermoregulatory, behavioral or performance responses. Egg production, feed conversion per dozen eggs corresponded to 81.1% of the differences between bacterial and fungal phytase supplementation and group control. Thus, we conclude that: (i) phytase dietary supplementation has no effect on the thermoregulatory responses of laying hens reared in a hot environment; (ii) birds supplemented with bacterial phytase showed higher egg production; and (iii) phytases (450 and 900 FTU) do not interfere with productive, behavioral and thermoregulatory responses.


Asunto(s)
6-Fitasa/administración & dosificación , Conducta Animal/efectos de los fármacos , Regulación de la Temperatura Corporal/efectos de los fármacos , Pollos/fisiología , Suplementos Dietéticos , Animales , Femenino , Calor , Oviposición/efectos de los fármacos
2.
R. cient. eletr. Med. Vet. ; (34): 14 p, jan. 2020. tab
Artículo en Portugués | VETINDEX | ID: vti-24846

RESUMEN

O presente trabalho teve como objetivo realizar revisão de literatura acerca da suplementação de fitase para tilápias. Por meio de consulta de periódicos científicos e livros. Foi realizado levantamento de dados, salientando a importância da utilização da fitase nos regimes intensivos de produção. Observou-se que a utilização da fitase pode promover efeitos positivos quando utilizada em rações formuladas com alimentos de origem vegetal. A fitase catalisa a hidrólise do fitato nos animais monogástricos, que não apresentam a enzima na forma endógena. A suplementação desta enzima beneficia o desenvolvimento dos peixes.(AU)


The present work aimed to perform a literature review about phytase supplementation for tilapia. By consulting scientific journals and books. Data collection was performed, highlighting the importance of the use of phytase in intensive production regimes. It was observed that the use of phytase can promote positive effects when used in diets formulated with foods of plant origin. Phytase catalyzes phytate hidrolysis in monogastric animals, which do not present the enzyme in endogenous form. Suplementation of this enzyme benefits fish development.(AU)


Asunto(s)
Animales , 6-Fitasa/administración & dosificación , 6-Fitasa/uso terapéutico , Tilapia , Eutrofización , Minerales en la Dieta , Suplementos Dietéticos
3.
PLoS One ; 14(5): e0217490, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31125379

RESUMEN

The objective of this study was to evaluate the effect of increasing doses of bacterial phytase (RONOZYME HiPhos) on performance and carcass characteristics of growing and finishing pigs. The study included 120 castrated males with initial weight of 23.21 ± 1.91 kg and 68 days of age, distributed in a randomized block design with five treatments and eight replicates with three animals each. The pigs were fed five corn-soybean meal-based diets: positive control (PC), supplemented with inorganic phosphorus and calcium; negative control (NC), with 0.13% reduction in available phosphorus and 0.11% in calcium; and three NC diets supplemented with 1,000, 2,000, and 3,000 phytase units (FYT)/kg in the feed. Compared with the NC diets without phytase, diets with 1,000, 2,000, and 3,000 FYT/kg inclusion increased the daily weight gain by +12% (quadratic, p<0.05) during the growing I period; +2.9, +2.9, and +10.5% (linear, p<0.01), respectively, during the growing II period; and +4.1, +5.1, and +8.2% (linear, p<0.001), respectively, over the entire experimental period. The daily feed intake increased by 0, +2.8, and +4.3% (linear, p<0.05), respectively, considering the entire experimental period; and the final live weight increased by +3.2, +4.2, and +6.1% (linear, p<0.001), respectively. The phytase treatments did not influence feed conversion ratio, carcass weight and yield, backfat thickness, loin depth and carcass lean meat. According to the European Carcass Classification (SEUROP), however, the animals fed the PC diet and the three phytase levels had more carcasses classified as E (between 55-60% lean meat) when compared to carcasses of pigs fed the NC. Supplementing increasing levels of phytase to a corn- and soybean meal-based diet with inorganic P and Ca reduction improved daily weight gain and feed intake of growing pigs, and such effects were maintained until slaughter age.


Asunto(s)
6-Fitasa/metabolismo , Alimentación Animal , Calcio de la Dieta/metabolismo , Citrobacter/enzimología , Fósforo Dietético/metabolismo , Porcinos/crecimiento & desarrollo , 6-Fitasa/administración & dosificación , Alimentación Animal/análisis , Crianza de Animales Domésticos , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Calcio de la Dieta/análisis , Dieta , Masculino , Carne/análisis , Fósforo Dietético/análisis , Porcinos/fisiología
4.
Semina Ci. agr. ; 40(2): 767-780, Mar.-Apr. 2019. tab
Artículo en Inglés | VETINDEX | ID: vti-19563

RESUMEN

Although phytase has been researched, new enzymes have been produced, leading to different animal responses. In this scenario, the present study proposes to evaluate the inclusion of a bacterial phytase produced by Escherichia coli in broiler diets based on corn and soybean meal, with or without nutrient reductions, on the performance, nutrient digestibility, phosphorus bioavailability, and bone minerals of those animals and on the economic viability of this practice. A total of 896 male broiler chickens were distributed into 32 experimental units, each housing 28 broilers. The experiment was set up as a completely randomized design with four treatments (Positive Control (PC)- diet meeting the nutritional requirements of the broiler chickens; Negative Control (NC) with reductions of 100kcal/kg of ME, 0.14% avP and 0.11% tCa; NC + phytase (500 FTU/kg); PC + phytase (500FTU/kg)) and 8 replicates. Phytase increased (p < 0.05) feed intake and body weight gain and improved feed conversion ratio in starter (1 to 21 days) and total (1 to 42 days) phases, respectively, compared with Negative Control diet without supplementation. The Negative Control + phytase diet also led to a feed intake similar to Positive Control in the starter and total phases. The inclusion of phytase without nutrient reductions improved (p < 0.05) feed conversion ratio in the starter phase, compared to...(AU)


Embora a fitase tenha sido estudada, novas enzimas foram produzidas, levando a respostas animais diferentes. Nesse sentido, o presente estudo teve como objetivo avaliar a inclusão de fitase bacteriana produzida por Escherichia coli em dietas à base de milho e farelo de soja, com ou sem redução de nutrientes sobre o desempenho, digestibilidade dos nutrientes, biodisponibilidade de fósforo, minerais ósseos e viabilidade econômica. Foram distribuídos 896 frangos de corte machos em 32 unidades experimentais, cada unidade constituída por 28 frangos. O delineamento foi inteiramente casualizado com quatro tratamentos (Controle Positivo (CP) - dieta que satisfaz os requisitos nutricionais das aves; Controle Negativo (CN) - reduções de 100 kcal/kg EM; 0,14% avP e 0,11% tCa); CN + fitase (500 FTU/kg); CP + fitase (500 FTU/kg)) e 8 repetições. A fitase aumentou (p < 0,05) o consumo de ração, o ganho de peso médio e melhorou a conversão alimentar nas fases inicial (1 a 21 dias) e total (1 a 42 dias), respectivamente, em comparação com a dieta Controle Negativo, sem suplementação. O Controle Negativo + fitase também apresentou consumo de ração semelhante ao Controle Positivo nas fases inicial e total. A inclusão da fitase sem redução dos requerimentos nutricionais (Controle positivo + fitase) melhorou (p < 0,05) a conversão alimentar na fase inicial, em comparação com a dieta Controle...(AU)


Asunto(s)
Animales , Enzimas/administración & dosificación , Enzimas/análisis , 6-Fitasa/administración & dosificación , 6-Fitasa/análisis , Disponibilidad Biológica , Pollos , Escherichia coli , Calcio de la Dieta , Fósforo Dietético , Suplementos Dietéticos
5.
J Sci Food Agric ; 98(13): 5089-5094, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29604090

RESUMEN

BACKGROUND: The effect of phytase supplementation with respect to a high sorghum grain diet on sheep voluntary feed intake, apparent nutrient digestibility, ruminal fermentation, phosphorus (P) excretion and blood serum P concentration was evaluated. RESULTS: Phytase supplementation significantly decreased fecal P excretion (P = 0.003), resulting in a 26% decrease in relation to the phytase free diet. Dry matter intake, nutrient digestibility, ruminal butyrate and serum P were not (P > 0.10) affected by the phytase level. Neutral detergent digestibility showed a tendency to increase linearly (P = 0.10) with increasing phytase levels. Ruminal pH was lower for phytase supplemented sheep, with a significant decrease (P = 0.007) at 9 h post feeding, whereas ruminal ammonia-N at 3 h post feeding was lower (P = 0.004) for the phytase treatment groups, resulting in a decreasing linear response (P = 0.001) with an increasing phytase dose. Duodenal pH was significantly reduced at 6 h post feeding. Propionate tended (P = 0.051) to be increased linearly as the phytase supplementation level increased. CONCLUSION: Exogenous phytase supplementation of high sorghum grain diets significantly decreased fecal P excretion in Rambouillet rams. Phytase supplementation appears to affect neutral detergent fiber digestibility, duodenal and ruminal pH, ammonia and propionate. © 2018 Society of Chemical Industry.


Asunto(s)
6-Fitasa/administración & dosificación , Alimentación Animal/análisis , Fósforo/sangre , Rumen/metabolismo , Ovinos/metabolismo , 6-Fitasa/metabolismo , Amoníaco/metabolismo , Animales , Disponibilidad Biológica , Fibras de la Dieta/metabolismo , Suplementos Dietéticos/análisis , Heces/química , Fermentación , Sorghum/metabolismo
6.
Poult Sci ; 96(9): 3305-3313, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28854754

RESUMEN

Two assays were conducted to evaluate nutritive value of canola meal (CM) fed to broiler chicks without or with a multi-carbohydrase (MC) preparation (700 U α-galactosidase, 2,200 U galactomannanase, 30,000 U xylanase, and 22,000 U ß-glucanase per kg of diet) and phytase (Phy, 500 FTU per kg of diet). Assay 1 determined apparent total tract digestibility (ATTD) of nutrients and metabolizable energy (AME) by the difference method. Assay 2 determined apparent ileal digestibility (AID) and standardized ileal digestibility (SID) of amino acids by the index method. Two reference diets (RD) - an 85% corn based and a 5% casein-cornstarch diet fortified with vitamins and minerals - were made for assays 1 and 2, respectively. For each assay, the test diets were made by mixing RD and CM 7:3 wt/wt basis and fed without or with MC or Phy or combination. A total of 245 day-old male broilers (Cobb 500) was allocated to 5 treatments to give 7 replicates (7 birds/cage). The birds were fed a commercial diet from day zero to 10 followed by assay 1 fed from d 11 to 18 and assay 2 fed from d 19 to 21. Excreta samples were collected on d 15 to18, and all birds were slaughtered on d 21 for ileal digesta. There was an interaction (P < 0.05) between MC and Phy on ATTD of DM, N, and P. There was no interaction (P > 0.05) between MC and Phy on AMEn; however, MC and Phy individually improved AMEn retention. Enzymes interacted (P < 0.05) on SID of Arg, His, Leu, Met, Thr, Ala, Asp, Gln, and Gly. In this context, feeding a combination of MC and Phy resulted in higher (P < 0.05) SID of Arg, His, Met, and Thr relative to single activity or control. Both enzymes improved (P < 0.05) SID of Lys independently. The combination of carbohydrase and Phy may be an effective strategy to improve amino acid utilization in CM for poultry.


Asunto(s)
6-Fitasa/metabolismo , Aminoácidos/metabolismo , Pollos/fisiología , Digestión/efectos de los fármacos , Metabolismo Energético/efectos de los fármacos , Glicósido Hidrolasas/metabolismo , 6-Fitasa/administración & dosificación , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales/efectos de los fármacos , Animales , Brassica/química , Dieta/veterinaria , Suplementos Dietéticos/análisis , Glicósido Hidrolasas/administración & dosificación , Íleon/efectos de los fármacos , Íleon/fisiología
7.
Poult Sci ; 96(5): 1204-1211, 2017 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-27697930

RESUMEN

An experiment was carried out to evaluate the digestibility and metabolizability of corn and a corn/soy-based diet with the inclusion or not of xylanase and/or phytase in broilers. In the trial, 1,120 broiler chicks were distributed according to a completely randomized experimental design, consisting of 16 treatments, with 10 replicates of 7 birds each. Treatments were evaluated following a factorial arrangement (4 × 2 × 2), with 4 xylanase levels (zero, 50, 100, or 150 fungal ß-xylanase units/kg; FXU), 2 phytase levels (zero or 1,000 phytase units/kg; FTU), and 2 diets (corn/soy or pure corn). The same basal diets were fed from one to 14 d post hatch for all birds, after which the experimental diets were provided until d 25. All birds were euthanized on d 25 for collection of ileal contents. Samples of feed, excreta, and ileal digesta were analyzed for determination of apparent ileal digestibility. The effect of xylanase on the coefficient of apparent dry matter metabolizability and apparent metabolizable energy was increased by the presence of phytase in the complete diet but not in the diet based on pure corn resulting in a diet*phytase*xylanase interaction (P < 0.01; P < 0.001, respectivaly). Equivalent effects were observed for the apparent coefficient of ileal protein digestibility in which xylanase effects were potentiated by the presence of phytase only in the complete diet, resulting in a significant 3-way interaction. In corn there was a limitation in improving digestibility when we added increasing levels of xylanase with phytase. Otherwise in the corn/soy-based diets, the enzymes were potencialized when they were added together. The fact that the effect of xylanase was enhanced by the presence of phytase in complete diets but not in pure corn may be associated with differences in substrate (arabinoxylan and/or phytate) concentration and presentation, diet nutrient balance, or other factors. It can be concluded that the interactive effects of xylanase and phytase can be substantial but may depend on the characteristics of the diet fed.


Asunto(s)
6-Fitasa/farmacología , Pollos/metabolismo , Dieta/veterinaria , Endo-1,4-beta Xilanasas/farmacología , Glycine max , Zea mays , 6-Fitasa/administración & dosificación , Alimentación Animal/análisis , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Suplementos Dietéticos , Digestión/efectos de los fármacos , Endo-1,4-beta Xilanasas/administración & dosificación , Metabolismo Energético , Heces/química , Íleon/metabolismo
8.
J Anim Physiol Anim Nutr (Berl) ; 99(1): 139-149, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24684499

RESUMEN

An experiment was conducted with broilers from 22 to 33 days of age to evaluate the efficiency of six microbial phytases supplemented in diets (1500 FTU/kg) that were formulated with three different calcium:available phosphorus (Ca:P(avail)) ratios (4.5:1.0, 6.0:1.0 and 7.5:1.0). A positive control diet without phytase was formulated with a Ca:P(avail) ratio of 7.5:3.4 to meet the nutritional requirements of the broilers. The P and ash contents of the tibia, magnesium in the plasma, performance, balance and retention of phytate phosphorus (P(phyt)), intake of total P and nitrogen (N), nitrogen-corrected apparent metabolizable energy and apparent digestibility of dry matter of the diets were not influenced (p > 0.05) by the type of phytase or the dietary Ca:P(avail) ratio. However, there was an interaction (p < 0.05) between the phytase type and the Ca:P(avail) ratio for the retention coefficients of total P, Ca and N. Phytase B resulted in the highest Ca deposition in the tibia (p < 0.01). Phytases D, E and F reduced the Ca concentrations in the tibia (p < 0.01) and plasma (p < 0.05). Phytase D increased the P level in the plasma and decreased the total P excretion (p < 0.01). Phytases E and F increased Ca excretion, while phytase A reduced it (p < 0.01). Regardless of the phytase type, increasing the dietary Ca:P(avail) ratio reduced (p < 0.05) the plasma P concentration and the excretion of total P and N and, conversely, increased (p < 0.05) the plasma concentration, intake and excretion of Ca. For the rearing period evaluated, it is possible to reduce the P(avail) of the diet to 1.0 g/kg when Ca is maintained at 7.5 g/kg, and the diet is supplemented with 1500 FTU of phytase A, C, D or E/kg. This diet allows the maintenance of performance and adequate bone mineralization, and it improves the Ca, total P and P(phyt) utilization in addition to reducing the excretion of N and P into the environment.


Asunto(s)
6-Fitasa/farmacología , Alimentación Animal/análisis , Calcio/farmacología , Pollos , Fósforo/farmacología , 6-Fitasa/administración & dosificación , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Calcio/administración & dosificación , Calcio/metabolismo , Dieta/veterinaria , Suplementos Dietéticos , Relación Dosis-Respuesta a Droga , Masculino , Fósforo/administración & dosificación , Fósforo/metabolismo
9.
Trop Anim Health Prod ; 45(4): 935-9, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23135985

RESUMEN

The addition of rice polishing (RP) and phytase enzyme to poultry diets was tested on 200 1-day-old broilers weighing 42 g. Birds were assigned to a completely random design with a 2 × 2 factorial arrangement with four treatments and five repetitions of ten birds each. The factors evaluated were RP level (0 and 15%) and phytase (0 and 150 g/ton). The trial was divided in two phases of 21 days each (42 days total). In phase 1, no treatment effects were observed (P>0.10) on poultry productive behavior. In the second phase (21 to 42 days) and on the total trial (1 to 42 days), there were no effects of the treatments on weight gain or feed intake (P>0.10). Feed conversion was affected by RP (P<0.01) but not by phytase addition (P>0.10). In conclusion, phytase did not affect broiler production with or without RP. Addition of 15 % RP in poultry diets represents an alternative to reduce feed costs.


Asunto(s)
6-Fitasa/administración & dosificación , Alimentación Animal , Pollos/crecimiento & desarrollo , Suplementos Dietéticos , Oryza , Animales , Peso Corporal/fisiología , Pollos/metabolismo , Ingestión de Alimentos/fisiología , México , Distribución Aleatoria , Clima Tropical
10.
Bol. ind. anim. (Impr.) ; 70(2): 149-157, 2013. tab
Artículo en Portugués | VETINDEX | ID: biblio-1434331

RESUMEN

Objetivou-se com esta pesquisa avaliar o desempenho e a qualidade óssea de poedeiras na fase de pós pico de postura, alimentadas com dietas contendo níveis de fósforo e fitase. Foi realizado um experimento com 384 poedeiras da linhagem Hy-line branca distribuídas em delineamento inteiramente casualizado em esquema fatorial 4 x 3, com 4 níveis de fósforo disponível e 3 níveis de fitase. O período experimental foi dividido em quatro ciclos de 28 dias, ao final de cada ciclo experimental foram determinados o consumo de ração, produção de ovos, peso de ovos, conversão alimentar, mortalidade, peso médio do ovo, espessura de casca, unidades Haugh e gravidade específica dos ovos. Ao final do período experimental foram determinadas as quantidades de cálcio e fósforo excretadas pelo método de coleta total de excretas e uma ave por unidade experimental foi sacrificada por deslocamento da articulação crânio-cervical para retirada dos ossos e avaliação da largura, comprimento e índice de robustez do fêmur e tíbia. Houve interação entre os níveis de fósforo e fitase para consumo de ração, conversão alimentar e percentual de postura. Para os níveis de inclusão de fitase todas as variáveis de qualidade de ovo não apresentaram diferenças significativas. Os tratamentos não afetaram as características ósseas das poedeiras.


The objective of this research was to evaluate the performance and bone quality of laying hens after peak production fed diets containing phosphorus levels and phytase. An experiment was conducted with 384 Hy-line distributed in a completely randomized in a factorial 4 x 3 with 4 levels of available phosphorus and 3 levels of phytase. The experimental period was divided into four periods of 28 days, at the end of each cycle were determined experimental feed intake, egg production, egg weight, feed conversion, mortality, and average egg weight, shell thickness, Haugh units and specific gravity. At the end of the experimental period were determined amounts of calcium and phosphorus excreted by the method of total excreta collection and a fowl per experimental unit was sacrificed for collection of bones and evaluation of width, length and level of robustness from femur and tibia. There was interaction between phosphorus levels and phytase on feed intake, feed conversion and percentage of posture. For inclusion levels of phytase all egg quality variables showed no significant differences. The treatments did not affect bone characteristics of laying hens.


Asunto(s)
Animales , Femenino , Calcio de la Dieta/administración & dosificación , Pollos/fisiología , Fósforo Dietético/administración & dosificación , 6-Fitasa/administración & dosificación , Huevos/análisis , Alimentación Animal/análisis , Desarrollo Óseo
11.
B. Inst. Pesca ; 34(1): 151-157, 2008. tab
Artículo en Portugués | VETINDEX | ID: vti-2674

RESUMEN

O fósforo (P) é um dos minerais de maior custo em rações para peixes. A maior parte do P em sementes de oleaginosas e cereais encontra-se ligado ao ácido fítico como fitato. Foi avaliado o efeito da suplementação de diferentes níveis de fitase em dietas para juvenis de jundiá sobre o desempenho produtivo e a retenção de minerais nos ossos. Foram utilizados 112 juvenis, em um delineamento inteiramente ao acaso com 4 tratamentos ( 0, 500, 1000 e 1500 FTU/kg de dieta) e 4 repetições. Os peixes foram alimentados na proporção de 10% da biomassa total durante 45 dias. Foram avaliados ganho de peso, comprimento padrão, sobrevivência, taxa de crescimento específico, fator de condição corporal, percentagem de cinzas nos ossos e concentração de P e cálcio nos ossos. Não houve efeito dos níveis crescentes de fitase na dieta sobre as variáveis avaliadas. Foi concluído que a suplementação de fitase na dieta (0 1500 FTU/kg) não afeta o desempenho produtivo nem a deposição de minerais nos ossos dos juvenis de jundiá. (AU)


Phosphorus (P) is one of the most expensive minerals in fish diets. Most of the P content in cereal grains and oilseed meals is bound to phytic acid, as phytate. This study was conducted to evaluate the effects of adding increasing levels of dielary phytase on performance and bone mineral retention of juveniles of catfish. One hundred and twelve juveniles were used in a completely randomized design, with 4 treatments (0, 500, 1000 e 1500 FTU/kg diet) and 4 replications. Fish were fed at 10% of total body weight during a 45-day period. The following variables were evaluated: weight gain, standard length, survival, specific growth, body condition ratio, ash percentage, and P and Ca concentration in the bones. No significant effect was found for the increasing levels of phytase on these variables. It was concluded that dietary phytase (0 and 1500 FTU/kg) do not affect the productive performance and minerals retention in the bones of the catfish juvenile. (AU)


Asunto(s)
Animales , Peces/crecimiento & desarrollo , 6-Fitasa/administración & dosificación , Fósforo , Alimentación Animal , Ácido Fítico , Minerales/metabolismo
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