924 resultados para Feed conversion


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The effects of the inclusion of raw glycerin (GLYC) and lecithin in the diet on egg production,egg quality and total tract apparent retention (TTAR) of dietary components was studied inbrown egg-laying hens from 23 to 51 wk of age. The experimental design was completelyrandomized with six diets combined as a 2 × 3 factorial with two levels of GLYC (0 vs.70 g/kg) and three animal fat to lecithin ratios (40:0, 20:20 and 0:40 g/kg). Each treatmentwas replicated eight times and the experimental unit was a cage with ten hens. Productionwas recorded by replicate every 28-d period and cumulatively. For the entire experiment,the inclusion of GLYC in the diet hindered feed conversion ratio per kilogram of eggs (2.071vs. 2.039; P < 0.05) but did not affect any of the other production or egg quality traits studied.The replacement of animal fat by lecithin (40:0, 20:20 and 0:40 g/kg) increased egg weight(60.1, 60.7 and 61.8 g, respectively; P < 0.001) and egg mass production (56.8, 57.5 and58.8 g/d, respectively; P < 0.01) and improved yolk color as measured by the DSM colorfan (9.2, 9.2 and 9.5, respectively; P < 0.001) and feed conversion ratio per kilogram of eggs(2.072, 2.068 and 2.027, respectively; P < 0.05). Feed intake, egg production and body weightgain, however, were not affected. The inclusion of GLYC in the diet did not affect nutrientretention but lecithin inclusion improved TTAR of dry matter (P < 0.05), organic matter(P < 0.05), ether extract (P < 0.001) and gross energy (P < 0.001). In summary, the inclusionof 70 g glycerol/kg diet hindered feed conversion ratio per kilogram of eggs but did notaffect any other production or digestibility trait. The replacement of animal fat by lecithinimproved egg weight, egg yolk color and nutrient digestibility. Consequently, lecithin canbe used as a lipid source in laying hen diets with beneficial effects on egg production

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This research studied the effects of additional fiber in the rearing phase diets on egg production, gastrointestinal tract (GIT) traits, and body measurements of brown egg-laying hens fed diets varying in energy concentration from 17 to 46 wk of age. The experiment was completely randomized with 10 treatments arranged as a 5 × 2 factorial with 5 rearing phase diets and 2 laying phase diets. During the rearing phase, treatments consisted of a control diet based on cereals and soybean meal and 4 additional diets with a combination of 2 fiber sources (cereal straw and sugar beet pulp, SBP) at 2 levels (2 and 4%). During the laying phase, diets differed in energy content (2,650 vs. 2,750 kcal AMEn/kg) but had the same amino acid content per unit of energy. The rearing diet did not affect any production trait except egg production that was lower in birds fed SBP than in birds fed straw (91.6 and 94.1%, respectively; P < 0.05). Laying hens fed the high energy diet had lower feed intake (P < 0.001), better feed conversion (P < 0.01), and greater BW gain (P < 0.05) than hens fed the low energy diet but egg production and egg weight were not affected. At 46 wk of age, none of the GIT traits was affected by previous dietary treatment. At this age, hen BW was positively related with body length (r = 0.500; P < 0.01), tarsus length (r = 0.758; P < 0.001), and body mass index (r = 0.762; P < 0.001) but no effects of type of diet on these traits were detected. In summary, the inclusion of up to 4% of a fiber source in the rearing diets did not affect GIT development of the hens but SBP reduced egg production. An increase in the energy content of the laying phase diet reduced ADFI and improved feed efficiency but did not affect any of the other traits studied.

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We studied the influence of pre-incubation weight of eggs (EW) laid by 24 wk-old brown laying breeders on egg production from 18 (start of egg production) to 22 wk of age (average egg production across EW treatments of 87.8%). The experiment consisted in 7 treatments based on the initial EW (47 to 53 g with 1 g difference between groups) Average BW of the extreme groups varied at hatching from 32.5 to 35.4 g, respectively. Feed intake, egg production, and egg weight were recorded weekly by replicate as well as for the entire experiment (18 to 22 wk of age). Hens were weighed by replicate at the beginning and at the end of the experiment. From these data, ADFI, egg production, egg weight, egg mass, feed conversion ratio per kilogram of eggs and per dozen of eggs, and BW gain were calculated by week and for the entire experiment. Also, the number of dirty, broken, and shell-less eggs was recorded daily by replicate in all eggs produced. Data were analyzed as a completely randomized design with 7 treatments differing in the initial pre-hatching EW. Effects of EW on the variables studied were partitioned into linear and quadratic components. EW did not affect the age at which pullets reached 50% egg production, cumulative egg production, or BW gain of the hens from 18 to 22 wk of age. Egg weight and the proportion of dirty, broken, and shell-less eggs were not affected by the BW of the pullets at hatching. In summary, small eggs (>47 g) laid by young, healthy laying breeders, can be used successfully to produce high quality pullets

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O objetivo do estudo foi avaliar o uso de bagaço de cana como enriquecimento ambiental para suínos a partir do comportamento e respostas fisiológicas do estresse causado pelo confinamento e mudança de ambiente, na fase de creche. O projeto foi conduzido no Laboratório de Biometeorologia e Etologia, da Faculdade de Zootecnia e Engenharia de Alimentos da Universidade de São Paulo, Pirassununga-SP, e no setor da Suinocultura da Prefeitura do Campus Administrativo Fernando Costa (PUSP-FC), entre os meses de abril e junho de 2015. Foram utilizados 66 leitões (NK75 X Naïma), machos e fêmeas desmamados aos 28 dias, separados em grupos homogêneos com relação ao peso, transferidos para baias da creche e distribuídos em dois tratamentos: Tratamento Enriquecido (TE) onde as baias foram fornecidas com cama profunda de bagaço de cana, de até 15 cm de profundidade e Tratamento Não Enriquecido (TNE) as baias foram utilizadas da forma convencional, sem cobertura no piso cimentado. Foram avaliadas diferentes respostas fisiológicas, especificamente, níveis de cortisol salivar, temperatura superficial por meio de um termómetro infravermelho e temperatura ocular a través de fotos termográficas. O comportamento dos leitões foi registrado e as análises das observações das atividades foram realizadas pelo efeito dos tratamentos e a interação do tempo. Os dados de desempenho dos animais foram analisados, igualmente como o Ganho de peso diário (GPD) e a conversão alimentar (CA). Animais que receberam enriquecimento ambiental apresentaram concentrações de cortisol mais baixas (P<0,001) durante a primeira semana pós-desmama. A partir da segunda semana pós desmama até o final da fase da creche houve efeito do tratamento (P<0,05), encontrando níveis de cortisol até quatro vezes mais altos para o TNE referentes aos níveis basais, enquanto o TE continua tendo níveis mais baixos (P<0,05). Animais que receberam enriquecimento ambiental tiveram maior frequência em comportamentos exploratórios (P<0,05) e maior atividade brincando (P<0,05) durante toda a fase experimental. Leitões que foram criados em baias pobres manifestaram maior frequência em comportamentos agonísticos (P<0,05) e em repouso (P<0,05). A correlação entre a temperatura superficial do dorso e termografia ocular indicou uma associação moderada positiva (P<0,0001) com a temperatura ocular mínima (r=0,43) e máxima (r=0,41). Apesar de não existir diferença estatística para o desempenho entre tratamentos (P>0,05), o TE apresentou maior ganho de peso diário (0,47±0,015 kg.dia-1) e total (23,47±0,73 kg.dia-1). A conversão alimentar foi maior no TE (2,88±0,25), provavelmente porque os leitões precisavam de mais alimento para compensar a energia gasta pela sua atividade de fuçar e brincar. Ambientes enriquecidos durante a fase da creche melhoram o bem-estar dos animais em confinamento, diminuindo o estresse pela desmama, motivando o animal a expressar comportamentos próprios da espécie suína, tais como fuçar e explorar.

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Para ser competitivo atualmente, o sistema intensivo de produção de suínos deve estar pautado na eficiência. A fim de obter esta eficiência produtiva, o avanço genético das ultimas décadas buscou por fêmeas suínas cada vez mais prolíficas. A prolificidade contudo, veio acompanhada por uma queda no consumo voluntário de alimento por parte das fêmeas, bem como um aumento na produção de leite, e no número de leitões nascidos; o aumento da leitegada, levou a uma redução do peso ao nascimento e um aumento da heterogeneidade entre os leitões. Como forma de contornar o problema, são oferecidas aos leitões dietas formuladas com ingredientes de alto valor biológico a partir dos sete dias de vida, procurando suprir a demanda nutricional do animal durante o período de amamentação e preparar seu sistema digestório para o desmame. Contudo, grande parte das dietas formuladas para os leitões neonatos são oferecidas aos animais em sua forma sólida. Neste projeto, avaliamos os efeitos sobre a performance de leitões neonatos e da performance reprodutiva da fêmea suína do oferecimento de uma dieta líquida para os leitões neonatos, dieta esta que foi disponibilizada aos animais através de um sistema automatizado que realizou a mistura do alimento em sua forma sólida com a água. Para tais avaliações, os leitões ao nascer foram alocados em três grupos distintos, recebendo a dieta em sua forma líquida, em sua forma sólida ou então apenas o leite materno. Foram avaliadas variáveis zootécnicas relacionadas aos leitões, como peso, ganho diário de peso, consumo de ração, conversão alimentar, mortalidade pré-desmame; frequência de dias com diarreia nos leitões em fase de maternidade e creche. Foram eutanasiados leitões aos 14 e aos 28 dias de idade, para a realização do exame morfométrico da altura de vilosidade, profundidade de cripta e a relação entre a altura de vilosidade e profundidade de cripta nas porções do duodeno, jejuno e íleo. Avaliamos também o impacto do uso da dieta líquida sobre o catabolismo sofrido pela fêmea durante a lactação, através da aferição do peso e da espessura de toucinho desta fêmeas durante o período lactacional e também a duração do intervalo desmame estro e a duração do estro subsequente ao desmame. Não verificamos contudo um melhor desempenho zootécnico dos leitões nos períodos de maternidade e creche, tão pouco uma alteração favorável quanto a frequência de dias com diarreia nas duas fases em relação aos leitões que não consumiram nenhum tipo de suplementação. Quanto aos parâmetros morfométricos do intestino delgado, apenas aos 28 dias de idade os leitões que receberam a dieta líquida apresentaram maiores alturas de vilosidades no íleo em relação aos leitões que consumiram a dieta sólida e os animais do grupo controle apresentaram menores profundidades de cripta no mesmo seguimento e idade quando comparados aos demais animais. Contudo, estas alterações não foram o suficiente para garantir diferenças na relação altura de vilosidade:profundidade de cripta. E ainda, a suplementação independente de sua forma não reduziu o catabolismo sofrido pela fêmea suína durante a lactação

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O Experimento foi realizado com o objetivo de avaliar a substituição parcial e total de plasma bovino por levedura hidrolisada na dieta de leitões desmamados no período de 21 a 47 dias de idade. Foram utilizados 1600 leitões da linhagem PIC, distribuídos em blocos ao acaso, com quatro tratamentos. As dietas foram divididas em quatro fases (pré-inicial I 22 a 28 dias; pré-inicial II 29 a 35 dias; inicial I - 36 a 47 dias e inicial II 48 a 63 dias). A inclusão percentual, Plasma: Levedura, nas dietas foi: T1 (6:0; 4:0; 2:0 e 0:0); T2 (3: 4; 2: 3; 1: 2 e 0: 0); T3 (1,5: 6; 1: 4,5; 0,5: 3 e 0: 0) e T4 (0: 8; 0: 6; 0: 4 e 0: 0). Cada tratamento teve 10 repetições (cinco de machos e cinco de fêmeas) totalizando 40 unidades experimentais com 40 animais cada. As variáveis zootécnicas avaliadas durante o período experimental foram: consumo de ração, ganho de peso, e conversão alimentar. Foram tomadas amostras de sangue de 5 animais por tratamento no dia de início do experimento, e de 10 animais por tratamento 25 dias depois. Foram quantificadas a IgA e a IgG. Os dados obtidos foram submetidos a análise de variância ANOVA, utilizando-se o teste Tukey para comparação das médias ao nível de significância de 5% utilizando o pacote estatístico SAS. Não houve diferença estatística nas quantidades de Ig A e Ig G circulante, nem na variação destas imunoglobulinas no tempo, entre os tratamentos. Considerando a análise dos dados conclui-se que nas condições estudadas, a utilização da relação percentual de (1,5: 6; 1: 4,5; 0,5: 3 e 0: 0) de plasma: levedura hidrolisada resultou um maior consumo de ração e ganho de peso dos animais, em comparação às outras proporções, e consequentemente podendo trazer um maior lucro para o produtor

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The effects of microbial phytase supplementation of phosphorus-adequate, wheat-based diets with available lysine : energy density ratios ranging from 0.75 to 0.90 g available lysine/MJ DE on growth performance of weaner pigs were investigated in 3 studies. In the first study, increasing levels of dietary phytate depressed growth rates (P<0.08) and efficiency of feed conversion (P<0.01) and phytase supplementation enhanced growth rates (P<0.05) and tended to improve feed efficiency (P<0.15). There were no significant interactions between dietary phytate and phytase inclusion to support the hypothesis that dietary substrate levels of phytate govern responses to phytase. However, in this and other studies, percentage increases in efficiency of feed conversion generated by phytase were positively correlated to dietary phytate concentrations to a significant extent (P<0.005), so it is possible that dietary substrate levels are of importance to the magnitude of responses following phytase supplementation. Diets with 3 levels of protein, expressed as 0.80, 0.85, and 0.90 g available lysine/MJ DE, were offered to pigs without and with phytase in the second study. Protein/amino acid levels or lysine : energy density ratios did not influence growth performance, which was not expected. However, phytase tended to increase growth rates (P<0.08) and improved feed efficiency (P<0.01). Although it is believed that phytase may have a positive influence on protein utilisation, this was not demonstrated in this experiment. In the third study, the simultaneous inclusion of phytase and xylanase feed enzymes in wheat-based weaner diets did not increase growth performance responses in comparison with phytase alone. Individually, phytase improved feed efficiency (P<0.05) and numerically increased growth rates (P<0.25). Although responses in growth performance of weaner pigs following phytase supplementation lacked consistency, they were generally positive and indicative of anti-nutritive properties of phytate that are unrelated to P availability. That these positive responses were observed in diets with suboptimal available lysine : energy density ratios is consistent with the possibility that phytate has a negative influence on protein utilisation, which is ameliorated by phytase. However, these antinutritive effects and their underlying mechanisms need to be better defined if full advantage of the potential protein-sparing effects of microbial phytase is to be taken.

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The growth performance and endocrine responses of male weaner pigs (3 to 8 weeks of age) was evaluated in two different environments (clean and dirty) and housing (single or groups of 10 pigs/pen) conditions. The dirty environment contained significantly elevated ammonia, carbon dioxide and dust levels compared with the clean environment. Pigs grew faster and consumed more feed in the clean environment and this was associated with reduced plasma cortisol concentrations compared with pigs in the dirty environment. Pigs housed in groups in the dirty environment had increased β-endorphin and decreased IGF-I concentrations compared to group housed pigs in the clean environment. Feed conversion efficiency did not differ due to environment or group housing. Plasma concentration of cortisol, p-endorphin, IGF-I and IGF-II did not differ between single and group housed pigs. Activity of the hypothalamic-pituitary-adrenal (HPA) axis was greater in response to environmental conditions than group housing, and this was associated with reduced growth in weaner pigs. © 2004 Elsevier B.V. All rights reserved.

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The nutritive value of transgenic peas expressing an a-amylase inhibitor (alpha-Ail) was evaluated with broiler chickens. The effects of feeding transgenic peas on the development of visceral organs associated with digestion and nutrient absorption were also examined. The chemical composition of the conventional and the transgenic peas used in this study were similar. In the two feeding trials, that were conducted normal and transgenic peas were incorporated into a maize-soybean diet at concentrations up to 500 g kg(-1). The diets were balanced to contain similar levels of apparent metabolisable energy (AME) and amino acids. In the first trial, the birds were fed the diets from 3 to 17days post-hatching and with levels of transgenic peas at 250 g kg(-1) or greater there was a significant reduction in body weight but an increase in feed intake resulting in deceased feed conversion efficiency. In the second trial, in which the birds were fed diets containing 300 g kg(-1) transgenic peas until 40 days of age, growth performance was significantly reduced. It was also demonstrated that the ileal starch digestibility coefficient (0.80 vs 0.42) was significantly reduced in the birds fed transgenic peas. Determination of AME and ileal digestibility of amino acids in 5-week-old broilers demonstrated a significant reduction in AME (12.12 vs 5.08 MJ kg(-1) DM) in the birds fed the transgenic peas. The AME value recorded for transgenic peas reflected the lower starch digestibility of this line. Real digestion of protein and amino acids was unaffected by treatment. Expression of a-Ail in peas did not appear to affect bird health or the utilisation of dietary protein. However, the significant reduction in ileal digestion of starch in transgenic peas does reduce the utility of this feedstuff in monogastric diets where efficient energy utilisation is required. (c) 2006 Society of Chemical Industry.

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Enzyme products did not have a significant effect (P>0.05) on weekly fed intake and weight gain of birds. But feed intake tended to drop and weight gain tended to increase in response to supplementation of the three enzymes. Weight gain of the birds was increased by 0.6% with lipase, 3.7% with phytase and 2.4% with xylanase. Xylanase had a marked effect (P

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The study aimed to evaluate performance, relative weight of the small intestine, digestibility and deposition of minerals in the bone of broilers supplemented with enzymatic complex (carbohydrases and phytase) in sorghum-based diets or sorghum and millet. In the experiments based of sorghum and sorghum and millet were used 912 day-old male and female Hubbard Flex chicks (50:50) were distributed in a completely randomized design in a 2x2 factorial arrangement (Feed Control base Sorghum (Contcs); FeedReducedbase Sorghum (RedS); Feed Control base sorghum + Enzymatic Complex (Contcs + Enz);. Feed reduced base sorghum + Enzymatic Complex (RedS + Enz) in the study of feed basis of sorghum and millet the design was similar (Feed Control base sorghum + millet ( ContSM); Reduced feed based on Millet + Sorghum (RedSM); Feed Control based Sorghum + Millet + EnzimaticComplex (ContSM + Enz); Reduced Feed base Sorghum+ Millet + Enzimatic Complex (RedSM + Enz). At 35 and 42 days of age were determined performance data: feed intake (CR), body weight (BW), feed conversion (FC), viability (VIAB), relative weight of the small intestine and deposition of minerals in the bone. The digestibility was evaluated sorghum grain size (crushed and whole) with and without exoenzimatico complex. They used 32 birds, eight birds per treatment, in periods from 17 to 21 (initial) and 31 to 35 days of age (fattening). The exoenzimático complex used in feed favored the weight gain results, feed conversion and bone mineralization when compared to a control diet not added to enzymes, demonstrating its effect on non-starch polysaccharides and phosphorus phytic present as anti-nutritional factors in these diets, increasing the digestibility and supply of metabolizable energy, essential amino acids, methionine and lysine and calcium and phosphorus for bone formation. It is concluded that a safe strategy for inclusion in feed is based on the reduction of energy levels, essential amino acids, methionine and lysine and calcium and phosphorus in the expected result of the constant activity of the enzymes of this exoenzimático complex.

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Oceans are experiencing increasing acidification in parallel to a distinct warming trend in consequence of ongoing climate change. Rising seawater temperatures are mediating a northward shift in distribution of Atlantic cod (Gadus morhua), into the habitat of polar cod (Boreogadus saida), that is associated with retreating cold water masses. This study investigates the competitive strength of the co-occurring gadoids under ocean acidification and warming (OAW) scenarios. Therefore, we incubated specimens of both species in individual tanks for 4 months, under different control and projected temperatures (polar cod: 0, 3, 6, 8 °C, Atlantic cod: 3, 8, 12, 16 °C) and PCO2 conditions (390 and 1170 µatm) and monitored growth, feed consumption and standard metabolic rate. Our results revealed distinct temperature effects on both species. While hypercapnia by itself had no effect, combined drivers caused nonsignificant trends. The feed conversion efficiency of normocapnic polar cod was highest at 0 °C, while optimum growth performance was attained at 6 °C; the long-term upper thermal tolerance limit was reached at 8 °C. OAW caused only slight impairments in growth performance. Under normocapnic conditions, Atlantic cod consumed progressively increasing amounts of feed than individuals under hypercapnia despite maintaining similar growth rates during warming. The low feed conversion efficiency at 3 °C may relate to the lower thermal limit of Atlantic cod. In conclusion, Atlantic cod displayed increased performance in the warming Arctic such that the competitive strength of polar cod is expected to decrease under future OAW conditions.

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Runting-stunting syndrome (RSS) in broiler chickens is an enteric disease that causes significant economic losses to poultry producers worldwide due to elevated feed conversion ratios, decreased body weight during growth, and excessive culling. Of specific interest are the viral agents associated with RSS which have been difficult to fully characterise to date. Past research into the aetiology of RSS has implicated a wide variety of RNA and DNA viruses however, to date, no individual virus has been identified as the main agent of RSS and the current opinion is that it may be caused by a community of viruses, collectively known as the virome. This paper attempts to characterise the viral pathogens associated with 2 – 3 week old RSS-affected and unaffected broiler chickens using next-generation sequencing and comparative metagenomics. Analysis of the viromes identified a total of 20 DNA & RNA viral families, along with 2 unidentified categories, comprised of 31 distinct viral genera and 7 unclassified genera. The most abundant viral families identified in this study were the Astroviridae, Caliciviridae, Picornaviridae, Parvoviridae, Coronaviridae, Siphoviridae, and Myoviridae. This study has identified historically significant viruses associated with the disease such as chicken astrovirus, avian nephritis virus, chicken parvovirus, and chicken calicivirus along with relatively novel viruses such as chicken megrivirus and sicinivirus 1 and will help expand the knowledge related to enteric disease in broiler chickens, provide insights into the viral constituents of a healthy avian gut, and identify a variety of enteric viruses and viral communities appropriate for further study.

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v. 17, n. 2, p. 206-216, abr./jun. 2016.

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Bio-floc shrimp culture systems have been investigated in an attempt to optimize water use and prevent the discharge of effluent into the environment. The importance of microalgae in maintaining water quality and nutrition of the shrimp is well known in conventional systems; however, its maintenance amid bio-flocs and its role in the shrimp performance in this system are still poorly understood. The aim of this study was to evaluate the contribution of diatoms in the performance of Litopenaeus vannamei reared during the nursery phase in intensive system with minimal water exchange. Shrimp (0.31 ± 0.10 g) were reared among diatoms, bio-flocs and the combination of the two forming the mixture medium. The survival of shrimp was high in all treatments (90–97%). However, the shrimp reared among diatoms showed higher weight gain (P\0.05) and feed conversion ratio significantly more efficient, reaching a value of 0.47. The results indicate the importance of diatoms in bio-floc culture systems and points out to future research in an attempt to maintain a constant presence of these microalgae in culture medium without requiring successive inoculations.