Revisão Crítica: Ácidos graxos essenciais na alimentação do camarão

Four types of poly unsaturated fatty acids (PUFA) are essential for all shrimp species, linoleic (LOA, 18:2n-6), alfa-linolenic (ALA, 18:3n-3), eicosapentaenoic (EPA, 20:5n-3) and docosahexaenoic (DHA, 22:6n-3) acids. Moreover, the arachidonic acid (ARA, 20:4n-6), even when present, seems to be, in crustaceans, not so important or yet dispensable. It is relevant knowing that cholesterol as much as PUFA are not well absorbed when not followed by a substantial amount of lecithin, reaching 5% of the ration. The sum of PUFA reaches around 3% of the diet, even varying according to the species, stage and ration type. For Penaeus monodon, a complex mathematic model was formulated in order to describe the relationships between the requirements of the cited PUFA. Industries involved with feed production on this segment must possess its own adaptation for another species. On the other hand, biochemical knowledge on PUFA n-3 series compounds functions are yet very delayed in comparison to the advances on pharmaceutical industry that investigates the n-6 series, with its prevalence in humans. In this review, the term PUFA is generically used to include ALA, LOA, DPA, EPA, ARA and DHA.Quatro tipos de ácidos graxos polinsaturado (PUFA) são essenciais para todas as espécies de camarão, são os ácidos linoleico (LOA, 18: 2n-6) alfa-linolénico (ALA, 18: 3n-3), eicosapentaenóico (EPA, 20: 5n-3 ) e docosahexaenóico (DHA, 22: 6n-3). Além disso, o ácido araquidónico (ARA, 20: 4n-6), mesmo quando presente, parece ser, em crustáceos, pouco importante ou ainda dispensável. É importante saber que os PUFA não são bem absorvidos quando não seguido por uma quantidade substancial de lecitina, atingindo 5% da ração. A soma de PUFA atinge cerca de 3% da dieta, mesmo variando de acordo com o tipo de espécies, estágio e ração. Para Penaeus monodon, um modelo matemático complexo foi formulado de modo a descrever as relações entre os requisitos de a citada PUFA. As indústrias envolvidas com a produção de alimentos desse segmento, devem possuir suas adaptações próprias para outras espécies. Por outro lado, os conhecimentos bioquímicos sobre as funções dos compostos da série n-3 dos PUFA estão ainda muito atrasados, comparado com os avanços da indústria farmacêutica que investiga a série n-6, com prevalência no homem. Nesta revisão, o termo PUFA é genericamente usado para incluir ALA, LOA, DPA, EPA, ARA e DHA

Critical review: cholesterol and fat-soluble vitamins on shrimp feeding

Four types of poly unsaturated fatty acids (PUFA) are essential for all shrimp species, linoleic (LOA, 18:2n-6), alfa-linolenic (ALA, 18:3n-3), eicosapentaenoic (EPA, 20:5n-3) and docosahexaenoic (DHA, 22:6n-3) acids. Moreover, the arachidonic acid (ARA, 20:4n-6), even when present, seems to be, in crustaceans, not so important or yet dispensable. It is relevant knowing that cholesterol as much as PUFA are not well absorbed when not followed by a substantial amount of lecithin, reaching 5% of the ration. The sum of PUFA reaches around 3% of the diet, even varying according to the species, stage and ration type. For Penaeus monodon a complex mathematic model was formulated in order to describe the relationships between the requirements of the cited PUFA. Industries involved with feed production on this segment must possess its own adaptation for another species. On the other hand, biochemical knowledge on PUFA n-3 series compounds functions are yet very delayed in comparison to the advances on pharmaceutical industry that investigates the n-6 series, with its prevalence in humans. In this review, the term PUFA is generically used to include ALA, LOA, DPA, EPA, ARA and DHA.Lipid quality on shrimp nutrition is very important, especially regarding to its content of essential substances. Nutrient intake is instinctively adjusted when animal selects its feeds in the wild. In captivity, it is possible to observe the cholesterol requirement, as in shrimps, as in other crustaceans, since they do not possess the ability to synthesize this indispensable nutrient for animal survival and development. Cholesterol is a relatively small part of the essential lipids for shrimp, and cannot be replaced by phytosteroids. Since cholesterol is the precursor of the ecdisone hormone (which controls molts), it is particularly more necessary during larvae stages. Also, fat-soluble vitamins are vital for shrimp growth. However, vitamins D and K functions are still partially known, because the premises of their functions in vertebrates have no equivalent in crustaceans. In this sense, only the relevance of vitamin E to protect PUFA has an explanation so far. On the other hand, the carotenoid astaxanthin appears to be as effective as an antioxidant that is difficult to justify the need for tocopherol. Dietetic imbalance in essential lipids turns shrimps susceptible to opportunistic infections. This review describes the cholesterol and fat-soluble vitamins importance in shrimp feeding

Growth curves, body nutrients deposition and determination of protein requirement for light and semi heavy hen pullets

Growth curves of pullets were adjusted to describe the deposition rates of body components and estimate the requirements in protein. Altogether 1500 poultry were randomly distributed in 30 repetitions of 25 birds. The experimental period was divided into four stages (1 to 4 weeks 5 to 11 weeks and 12 to 16 weeks old). The rations formulated based on corn and soybean meal were offered the will. Weekly, pullets were heavy and two birds separates by lineage to be in determining chemical composition of body nutrients. The informations was used to obtain the parameters of the Gompertz model. Allometric relationships were used to describe the changes in body composition in protein, lipid, ash and water in the body gutted and without feathers. The data of body weight growth of the strains pullets Dekalb White and Bovans Goldlina fit to the Gompertz function. The allometric coefficients of fat, water and mineral matter on the basis in proteic weight of the lines Dekalb and Bovans lines were respectively: 0.114 vs 1.160; 0.811 vs 0.429; 0.930 vs 0.189. There are differences among genotypes for growth rates and deposition of body nutrients and fearther. The light-line is earlier. The total protein requirements (maintenance and gain) for pullets of 1 to 4, 5 to 11 and 12 to 16 weeks of age were respectively 4,41; 9,814; 12,612 g / d for Dekalb White and 4.82; 8,859; 7,673g / d to Bovans Goldline. The aim of this work was to determine growth curves and body nutrients deposition by using Gompertz equation, and to estimate protein requirement in light and semi heavy hen pullets. In total, 1,500 hen pullets were distributed at random into 30 repetitions of 25 birds each. Experimental period was divided into three steps (1st to 4th, 5th to 11th and 12th to 16th weeks of age). Rations were formulated based on corn and soybean meal and offered ad libitum. Birds were weighed weekly. Two birds per repetition were used to determine chemical body composition and data were used to obtain Gompertz model parameters. Allometric ratios were used to describe changes in the body composition in protein, lipid, mineral matter and water in the eviscerated and featherless body. Weight-age data of Dekalb White and Bovans Goldline pullets were well described by Gompertz function. Allometric coefficients of fat, water and mineral matter in function of the protein body weight were, respectively: 0.114, 0.811 and 0.930 for Dekalb line and 1.160, 0.429 and 0.189 for Bovans line. There are differences between lines for growth rates and body nutrients and feathers deposition, with Dekalb line being the most precocious. Total protein requirements (maintenance and growth) for pullets from 1st to 4th, 5th to 11th and 12th to 16th weeks of age were 4.41; 9.814 and 12.612 g˙d-1 for Dekalb White and 4.82; 8.859 and 7.673 g˙d-1 for Bovans Goldline, respectively

Reduction of the nutritional values of diets for hens through supplementation with phytase

Objetivou-se avaliar os efeitos da redução dos níveis nutricionais de dietas para poedeiras marrons em pico de postura sobre o desempenho das aves, a qualidade dos ovos e os parâmetros ósseos. No total foram avaliadas oito dietas, cada uma com cinco repetições de oito aves: 1. controle: formulada para suprir as exigências das aves; 2) controle + 0,03% ou 600 FTU; 3) 15% PB; 2.800 kcal de EM; 3,8% Ca e 0,28% Pd; 4) dieta 3 + 0,03% ou 600 FTU; 5) 14% PB; 2.750 kcal de EM; 3,4% Ca e 0,23% Pd; 6) dieta 5 + 0,03% ou 600 FTU; 7) 13% PB; 2.700 kcal de EM; 3,0% Ca e 0,18% Pd; e 8) dieta 7 + 0,03% ou 600 FTU. A redução dos níveis nutricionais prejudicou o desempenho das aves, principalmente a produção e massa de ovos, que melhorou com a inclusão de fitase nas dietas. Os parâmetros de qualidade dos ovos, no entanto, não se alteraram com a redução até o nível de 15% de PB; 2.800 kcal de EM/kg; 3,80% Ca e 0,280% Pd, o que não se repetiu nos níveis com menor densidade nutricional. Não houve efeito da redução dos níveis nutricionais sobre os parâmetros ósseos avaliados, exceto a resistência, que melhorou com a suplementação de fitase no nível de 600 FTU. A redução nos níveis nutricionais da dieta para 15% de PB, 2.800 kcal/kg de EM, 3,8% de Ca e 0,280% de Pd com a adição de 600 FTU não prejudica a produção nem a massa de ovos e melhora a saúde óssea das aves.The aim of this work was to evaluate the effects of the reduction on nutritional levels of diets for semi-heavy hens during the laying peak on performance, egg quality and bone parameters. A total of eight diets were evaluated, each one with five repetitions of eight birds: 1) control: formulated to supply requirements by the birds; 2) control + 0.03% or 600 FTU; 3) 15% crude protein; 2,800 kcal ME; 3.8% Ca and 0.28% aP; 4) diet 3 + 0.03% or 600 FTU; 5) 14% crude protein; 2,750 kcal ME; 3.4% Ca and 0.23% aP; 6) diet 5 + 0.03% or 600 FTU; 7) 13% crude protein; 2,700 kcal ME; 3.0% Ca and 0.18% aP; and 8) diet 7 + 600 FTU. The reduction of the nutritional levels harmed the performance of the birds, particularly egg production and egg mass, which improved by the inclusion of phytase in the diets. However, the parameters for egg quality did not change as the level was reduced down to 15% crude protein; 2,800 kcal ME/kg; 3.80% Ca and 0.280% aP, which was not repeated in the levels with lower nutritional density. Reduction of nutritional levels did not affect the evaluated bone parameters, except for resistance, which improved as phytase was added at the level 600 FTU. Reduction on the diet nutritional levels to 15% crude protein; 2,800 kcal ME/kg; 3.80% Ca and 0.280% aP with the addition of 600 FTU of phytase does not impair egg production neither egg mass and improve the bone health of birds

Chlorine requirement for Japanese laying quails

The objective of this study was to determine the chlorine nutritional requirement of Japanese Quails during the laying phase, based on performance and egg quality parameters. A total of 240 Japanese quails were distributed according to a randomized block design, with five treatments and six replicates, with 8 birds each. The experiment lasted 84 days, divided in four cycles of 21 days each. Treatments consisted of a basal diet formulated to meet the nutritional requirements, except for chlorine, and four supplementation levels with ammonium chloride, generating the levels 0.8; 1.6; 2.4; 3.2 and 4.0 g/kg. The parameters evaluated were: feed intake (g/bird/day), egg production (egg/bird/day), egg weight (g), egg mass (g), egg mass conversion (g/g), conversion per dozen eggs (kg/dz), weight of yolk (g/100 g of egg), albumen (g/100g of egg) and shell (g/100 g of egg), specific gravity (g/cm³) and shell thickness (mm). As a result of this study, feed intake, egg weight, weights of albumen, yolk, shell and specific gravity were not affected by treatments. There was a quadratic behavior for egg production, egg mass, egg mass conversion, conversion per dozen eggs and shell thickness according to the chlorine levels in the diets, with the requirements for those parameters established at 1.54; 1.37; 1.39 and 2.78 g/kg, respectively. The recommendation is 1.39 g/kg of chlorine and 244.22 mEq/kg of electrolyte balance in diets for Japanese quails