Promotor del crecimiento en la producción de pollos de y cerdos

The pressure for reducing the use of antibiotic growth promoters (AGP) in livestock is an irreversible process, and several countries are adhering to the restrictions on AGP usage. Sweden was the first country that changed laws of AGP usage, and the USA is not only limiting AGP use but also moving towards a significant reduction of general antibiotics usage. The increasing pressure to prohibit the use of these additives is based on the possibility of allergic reactions and induction of cross-resistance of pathogenic bacterial strains in people. In broiler and pig production the AGP is used with the objective of obtaining better results of weight gain and feed conversion. However, considerable variability in performance response to AGP has been observed, contingent on genetic potential, phase of rearing, as well as hygiene and management practices. It is clear that AGP restrictions in the production of animal food are a growing process and therefore its consequences must be evaluated, including its effect on animal performance and the economic results of such restriction. Noting these considerations, the purpose of this review is to disseminate relevant information about the use of antibiotic growth promoters in broiler and pig production.A pressão para reduzir o uso de antibióticos promotores de crescimento (AGP) na pecuária é um processo irreversível, e vários países estão aderindo às restrições ao uso de AGP. A Suécia foi o primeiro país que mudou as leis de uso de AGP, e os EUA não estão apenas limitando o uso de AGP, mas também caminhando para uma redução significativa no uso geral de antibióticos. A crescente pressão para proibir o uso desses aditivos baseia-se na possibilidade de reações alérgicas e indução de resistência cruzada de cepas bacterianas patogênicas em pessoas. Na produção de frangos e suínos, o AGP é utilizado com o objetivo de obter melhores resultados de ganho de peso e conversão alimentar. No entanto, foi observada uma variabilidade considerável na resposta do desempenho ao AGP, dependente do potencial genético, da fase de criação e das práticas de higiene e manejo. É perceptível que as restrições de AGP na produção de alimentos para animais são um processo crescente e, portanto, suas consequências devem ser avaliadas, incluindo seu efeito no desempenho animal e os resultados econômicos. Observando essas considerações, o objetivo desta revisão é disseminar informações relevantes sobre o uso de antibióticos promotores de crescimento na produção de frangos e suínos.La presión para reducir el uso de antibióticos que promueven el crecimiento (AGP) es un proceso irreversible, y varios países se están adhiriendo a las restricciones sobre el uso de AGP. Suecia fue el primer país en cambiar las leyes de uso de AGP, y Estados Unidos no solo está limitando el uso de AGP, sino que también está reduciendo significativamente el uso general de antibióticos. La creciente presión para prohibir el uso de estos aditivos se basa en la posibilidad de reacciones alérgicas e induce resistencia cruzada de cepas bacterianas patógenas en las personas. En la producción de pollos y cerdos, se usa AGP para obtener mejores resultados de aumento de peso y conversión alimenticia. Sin embargo, se observó una variabilidad considerable en la respuesta de desempeño al AGP, dependiendo del potencial genético, la fase de reproducción y las prácticas de higiene y manipulación. Es notable que las restricciones AGP en la producción de alimentos para animales es un proceso creciente y, por lo tanto, sus consecuencias deben ser evaluadas, incluido su efecto sobre el rendimiento animal y los resultados económicos. Observando estas consideraciones, el propósito de esta revisión es difundir información relevante sobre el uso de antibióticos que promueven el crecimiento en la producción de pollos y cerdos

Omni-directional catadioptric vision for soccer robots

This paper describes the design of a multi-part mirror catadioptric vision system and its use for self-localization and detection of relevant objects in soccer robots. The mirror and associated algorithms have been used in robots participating in the middle-size league of RoboCup — The World Cup of Soccer Robots.This work was supported by grant PRAXIS XXI BM/21091/99 of the Portuguese Foundation for Science and Technolog

Modeling the performance of broilers under heat stress

A meta-analysis was developed to model performance depression in heat stress (HS), to analyze the influence of HS type (cyclic or constant), and to assess the correlation between dietary electrolyte bal- ance (DEB) and HS in broilers. Two databases (Dat) with performance and temperature were constructed (initial phase − up to 21 d of age − 14 articles, 7,667 ani- mals, average replicate number treatment-ARN/T, 5 and growing phase − over 21 d of age − 74 articles and 25,145 broilers, ARN/T, 7). The criteria for article selec- tion were (1) experiments using at least 2 temperatures (thermoneutral and high temperature); (2) results of ADFI and ADG; (3) feed and water ad libitum during the experiment. Each treatment was classified as cyclic or constant HS and the HS group response was calcu- lated relative to the thermoneutral group. Performance was evaluated as raw data or as relativized information (indicated as “HS effect or 61⁄4”), expressed as a percentage of the difference between results. The models to predict “HS effect” showed that for the initial phase, only ADG was influenced by HS, while for the grower phase, pre- diction equations were created for ADFI and ADG. Con- sidering the simplest models, there was a reduction of 1.4% in ADFI and 2.1% in ADG for each unit (°C) above the upper critical temperature for broilers older than 21 d. Feed conversion (FC) was not affected by HS in any of the studied phases. Constant HS proved to be more negative than cyclic HS to broiler performance after 21 d of age. The relation between DEB and performance of broilers under HS was analyzed considering broilers over 21 d of age, and very weak correlations were observed. It was concluded that HS affects broilers over 21 d more, although FC is not affected. ADFI is the most important variable affected by HS and the relation between the DEB of the diet and HS is very weak. The empirical models generated in this study accurately predicted ADG and ADFI of broilers exposed to HS and can be used to minimize those effects on poultry production

Effect of an enzyme blend on the performance, diet metabolizability, phosphorous retention, and bone mineralization of broilers fed diets containing defatted rice bran

An experiment was conducted to evaluate the effect of an enzyme blend (EB) on the performance, diet metabolizability, phosphorus (P) retention, and bone mineralization of broilers fed diets containing 10% defatted rice bran (DRB). In total, 432 one- to 38-d-old male Cobb broilers were evaluated according to a completely randomized experimental design in 3 x 2 factorial arrangement. Three diets were tested with two nutrient reductions (NR) in the matrix (standard diet; NR I of 75 kcal/kg ME, 0.1% Ca and 0.1% available P; and NR II of 100 kcal/kg ME, 0.1% Ca and 0.1% available P) with or without the addition of an EB (200 g/t). The coefficients of total tract apparent retention (CTTAR) of the diets and P retention were determined by collecting excreta during two periods (14 to 17 and 28 to 31 d). As expected, birds fed the standard diet had higher BW, BW gain, and G:F compared to birds on the NR diets. The EB did not show any positive effects on CTTAR or on performance; however, birds fed the EB retained 6.58% more P from d 14 to 17 (p ≤ 0.07) and 8.55% from d 28 to 31 (p < 0.05). Tibiotarsus ash percentage also increased by 2.45% (p ≤ 0.06) on d 38. In diets containing 10% DRB, the enzyme blend showed biological activity improving P retention and tibiotarsus mineralization

Desempenho de frangos de corte suplementados com diferentes fontes e níveis de colina na dieta

Two experiments were carried out to evaluate the bioequivalence of a commercial phosphatidylcholine source (Biocholine™) as an alternative to choline chloride and the choline requirements of broilers of a fast-growth strain. In Experiment I, 672 broilers were fed four Biocholine™ levels (0, 100, 200, or 300 mg/kg) and three choline levels (200, 400, or 600 mg/kg) supplied as choline chloride between 4 and 28 days (d) of age. In Experiment II, 462 broilers received diets supplemented with 0, 200, 400, 600 or 800 mg/kg choline as choline chloride. In both experiments, diets were based on white rice, soybean meal, and corn gluten. In Experiment I, birds fed choline chloride presented higher feed intake than those fed Biocholine™. Both choline supplements linearly improved feed conversion ratio (FCR) between 15 and 28 d, but the curves presented different slopes, showing that one unit (U) of Biocholine™ was equivalent to 2.52 U of choline supplied as choline chloride. In Experiment II, the supplementation of choline had a quadratic effect on weight gain (WG) but did not affect FCR. Choline requirements for WG were determined as 778, 632, and 645 mg/kg for 1-7, 1-35, and 1-42 d of age, respectively.Dois experimentos foram conduzidos para avaliar a bioequivalência de uma fonte comercial de fosfatidilcolina (Biocholine®) como alternativa ao cloreto de colina e as exigências de colina de frangos de rápido desempenho. No Experimento I, 672 frangos foram alimentados com quatro níveis de Biocholine® (0, 100, 200 ou 300 mg/kg) e três níveis de colina (200, 400 ou 600 mg/kg) supridas pelo cloreto de colina entre 4 e 28 dias de idade. No Experimento II, 462 frangos receberam dietas suplementadas com 0, 200, 400, 600 ou 800 mg/kg de colina através do cloreto de colina. Em ambos os experimentos, as dietas foram à base de arroz branco, farelo de soja e glúten de milho. No Experimento I, as aves alimentadas com cloreto de colina apresentaram maior consumo de ração em relação àquelas alimentadas com Biocholine®. Ambas as fontes de colina melhoraram linearmente a conversão alimentar entre 15 e 28 dias, mas as curvas apresentaram diferentes inclinações, mostrando que uma unidade de Biocholine® foi equivalente a 2,52 unidades de colina suprida na forma de cloreto de colina. No Experimento II, a suplementação de colina apresentou efeito quadrático sobre o ganho de peso sem afetar a conversão alimentar. As exigências de colina para ganho de peso foram 778, 632 e 645 mg/kg para as fases de 1-7, 1-35 e 1-42 dias de idade, respectivamente

Digestibility of total, insoluble and soluble dietary fiber of sows during gestation

When the level of fiber is increased, it is important to evaluate the impact of this addition upon the nutrients digestibility. The present study evaluated the effect of variation in the amount of total dietary fiber in sow diets, provided from 74 to 87 days of gestation, on the digestibility of nutrients. Thirty three sows were used in a randomized experimental design. The amounts of total dietary fiber in three treatment diets were 15.6; 22.3 and 28.2%. To increase the amount of dietary fiber, rice grain and soybean meal were partially substituted for defatted rice bran and soybean hulls. The daily consumption of nutrients and energy was similar between the 74 to 87 days of gestation, differing only in the volume of ration consumed, which was 2.1; 2.2 and 2.4 kg/day. During gestation, the increase in total dietary fiber resulted in a significant decrease in the apparent total tract digestibility of total dietary fiber, insoluble dietary fiber e soluble dietary fiber. Increasing the amount of total dietary fiber reduced the digestibility of nutrients, mainly of the total dietary fiber and insoluble dietary fiber

High-energy diet does not overcome the negative impact of conjugated linoleic acid on young broiler performance

The aim of this study was to evaluate the effect of conjugated linoleic acid (CLA) supplementation in diets with different energy levels in broiler performance. Birds were offered a starter (1-21 d), grower (22-35 d) and finisher (36-42 d) diets; wherein soybean oil was replaced by CLA. The study consisted of a 3 × 2 factorial arrangement with two CLA levels (0 and 1%) and three energy levels (3050, 3100 and 3150 ME kg-1 diet). During the grower and finisher periods, birds were fed diets with same energy level and CLA supplementation was maintained the same. Growth performance was assessed weekly, and carcass and cuts yield were assessed at 42d. Interaction effect of CLA by energy level was observed in broiler performance and carcass yield throughout the study (p > 0.05). During the overall period (1-42 d) broiler performance was not affected by CLA (p > 0.05).However, CLA supplementation (1%) decreased weight gain (p 0.05). The increase in dietary energy was not able to compensate the negative effect on growth performance of broilers supplemented with 1% CLA at the starter period

An in-situ assessment of Dorsal Cranial Myopathy in broilers, approaching regarding meteorological influences in South Brazil, classification, and appearance of the lesions during industrial processing

Broiler meat is a high-quality food for humans, and is worldwide consumed. Brazil plays an important role in the poultry industry and in its South region is situated the most important pro- ducer. Recently, alterations on the meat aspect have aroused the interest of researchers to clarify their causes. The objective of this investigation was to evaluate the relationship between environ- mental conditions and seasons on the prevalence of Dorsal Cranial Myopathy (DCM) and also, to generate a DCM classification in scores, for griller-type broilers. Carcasses were picked out from several stages of industrial processing from a slaughterhouse located in South Brazil. The preva- lence of DCM was measured using the database of partial condemnations of the Official Inspection Service during 19 months. Meteorological data were obtained from the National Institute of Meteo- rology (in Portuguese Instituto Nacional de Meteorologia- INMET), of the Ministry of Agriculture, Livestock and Supply. In addition, microorganisms with public health importance were measured on samples taken from the muscles with DCM. The prevalence of DCM was compared among sea- sons using Analysis of Variance (ANOVA). The relation with other environmental conditions was accessed using a principal component analysis. Partial condemnations by DCM were higher (P 0.05). Visually, it could be noted that the hemorrhagic lesion of the Anterior latissimus dorsi (ALD) muscle diminished during the processing line, making the DCM imperceptible, even in those carcasses with severe DCM score at the beginning of the process. In conclusion, the climate features approached here could be correlated to this emerging myopathy. However, this lesion does not represent a food security issue for the consumers regarding evaluated microorganisms, as this kind of lesion tends to disappear in the final sellable product

Principios básicos en la formulación de raciones

O desempenho dos animais de uma criação está intimamente relacionado com o programa nutricional desenvolvido na propriedade. As definições das características dos animais e dos alimentos que estarão envolvidos no programa nutricional são de fundamental importância, tornando possível formular uma ração que atenda as necessidades nutricionais dos animais e que otimize a utilização dos alimentos. Desta forma, o objetivo desta revisão é abordar os princípios básicos que devem ser considerados para a formulação de uma ração e apresentar, de forma didática, exemplos de formulação de ração que podem ser realizados manualmente ou com o auxílio de uma calculadora.The performance of farm animals is closely related to the nutritional program developed on the property. Making the definitions of the characteristics of the animals and food that will be involved in the nutritional program is of fundamental importance, as it will make it possible to formulate a ration that will meet the nutritional needs of the animals and that will optimize the utilization of the food. Thus, the aim of this review is to present the basic principles that must be considered for the formulation of a feed and to demonstrate, in a didactic way, examples of feed formulation that can be performed manually or with the aid of a calculator.El rendimiento de los animales de granja está estrechamente relacionado con el programa nutricional desarrollado en la propiedad. Las definiciones de las características de los animales y los alimentos que participarán del programa nutricional son de fundamental importancia, ya que permitirá formular una ración que satisfaga las necesidades nutricionales de los animales y que optimice la utilización de los alimentos. Por lo tanto, el propósito de esta revisión es presentar los principios básicos que deben considerarse para la formulación de un alimento y demostrar, de manera didáctica, ejemplos de formulación de alimentos que pueden realizarse manualmente o con la ayuda de una calculadora

The use of artificial intelligence for the prediction of productivity parameters in swine culture

In similar conditions of food handling and genetics, there are large differences in the final productivity of farms, resulting from inherent factors of the production system. This fact predisposes the need of studies on optimizing the rearing conditions of the farms, in order to verify the main limitations for the producers. Therefore, the present study aims to generate predictions of the swine productivity in the finishing phase, using variables related to their profiles and the production results achieved. 107 farmers belonging to a swine cooperative were considered in the study, located in 47 counties at the Taquari valley region, Brazil. Predictions were generated through the aid of neural networks, and the findings show that Artificial Neural Networks (ANN) can predict the productivity variables Feed Conversion, Mortality and Average Daily Gain for the proposed case