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The objective of this study was to evaluate the relative bioavailability (RB) of manganese (Mn) proteinate compared to Mn sulfate for broilers fed a diet based on corn and soybean meal for 20 d. The diets of 1,350 male Cobb broilers were supplemented with 0, 35, 70, 105, or 140 mg of Mn/kg of feed in the form of Mn sulfate or Mn proteinate. Weight gain, feed intake, feed conversion, bone strength, and Mn concentration in the tibia and liver, as well as the concentration of type I collagen in the tibia, were evaluated. No differences were observed for performance variables (P > 0.05) or for type I collage concentration in broiler tibia (P > 0.05), regardless of the source and level of supplementation used. Relative bioavailability was determined using bone strength values and Mn concentration in the tibia and liver, assuming Mn sulfate as the standard source (100%) by the slope-ratio method. The RB of Mn proteinate based on bone strength was 111%, based on liver Mn concentration was 128%, and based on tibia Mn concentration was 105%. Manganese proteinate was more bioavailable than Mn sulfate; it can be an important source of supplementation to improve bone quality in broilers.

A sanitation method that could continually clean and disinfect the air and surfaces in a hatchery could provide a second layer of microbial reduction on top of routine cleaning and disinfection. A gaseous dry hydrogen peroxide (DHP) system has been used in other facilities for this purpose and could have potential for use in chicken hatcheries. Because the DHP is a true gas and can permeate through the entire hatchery space, contact with eggs during storage and incubation could potentially interfere with normal hatching processes. Therefore, the aim of this study was to evaluate the effects of the DHP system on hatching parameters and chick quality. A total of 3,960 hatching eggs were collected from an ∼40-week-old Ross 308 broiler breeder flock and distributed in 2 treatments: treated and nontreated. For the treated group, the egg cooler was cleaned, and 1 DHP generator was placed inside. Two other DHP generators were placed in the common area outside as well. Both areas were treated for 7 D before placement of eggs, and then eggs were collected and placed inside the cooler over a 4-day period. Eggs were then stored for an additional 3 D after the last collection. Dry hydrogen peroxide levels were recorded each day during storage. For the nontreated group, all DHP machines were removed from the cooler and external room, and the egg cooler was cleaned. Eggs were collected in the same way for the control group as the treated group. After storage, eggs were placed into a single stage Natureform incubator. The eggs exposed to DHP showed higher (P

Broilers are subject to adverse environmental conditions, especially temperature, which decreases performance and increases disease vulnerability. Understanding how the mechanisms involved in therm...

Introdução: As infestações por ectoparasitos e alguns artrópodes são responsáveis ​​por causar irritação severa, dermatite e transmissão de alguns patógenos às aves, resultando em perda de peso, queda na taxa de postura e atraso no desenvolvimento do lote de aves. Objetivo: Validar um questionário para coleta de dados de granjas avícolas, a fim de quantificar a ocorrência e os fatores de risco de ectoparasitos e alguns artrópodes. Materiais e Métodos: Um questionário foi desenvolvido com questões objetivas e categóricas sobre quaisquer ectoparasitos de aves. As questões foram elaboradas de forma a diferenciar falhas no preenchimento do entrevistador, evitando a ausência de resposta devido à inexistência do fenômeno ou à falta de conhecimento do entrevistado. O questionário inicial foi aplicado a 10 trabalhadores de fazendas de camada ou de frangos de corte em Minas Gerais e submetidos a um teste de validação teste-reteste com intervalo semanal. Resultados: O questionário final apresentou 89 alternativas de questões, sendo que questões de tamanho da gaiola, material predominante para suporte de gaiola e presença de espécies indefinidas de moscas apresentaram baixa concordância e foram removidas. Outras questões sobre características tipológicas e estruturais, incluindo métodos de controle contra ácaros ou piolhos, a presença de frangos de quintal ou outras aves que vivem nas proximidades mostraram concordância muito boa ou excelente. Questões relacionadas à presença de outros ectoparasitos e pragas mostraram concordância regular a excelente, embora requerendo mais explicações sobre diferenças entre ácaros e piolhos. Conclusão: O questionário final foi válido e confiável para a coleta de dados para análise e quantificação dos riscos associados às infestações de ectoparasitos e outros artrópodes.

The present study aimed to determine the effects of egg type (nest clean or floor eggs) on eggshell microbiological, hatching performance, chick quality, yolk sac microbiology, and the interaction between egg type and post-hatch use of ceftiofur on broiler performance at 7, 14, 21, 28 and 35 days. A total of 2500 fertile eggs were obtained from a commercial flock of Cobb Slow® broiler breeders. Half of the eggs were collected directly from the floor, and the other half were collected from the nests. Microbiological evaluation of eggshells was performed before and after sanitization. After hatching, 420 male chicks were randomly selected and distributed in a completely randomized design in a 2 × 2 factorial scheme, separated by the type of egg (clean nest or floor) and the inclusion or not of subcutaneous ceftiofur, totaling four treatments. Egg type did not influence hatchability although the contamination level was 1.3% higher. The body weight and body weight gain of chicks at seven days were greater for chicks from nest eggs that received ceftiofur than chicks from floor eggs that also received ceftiofur. There was no interaction between the studied factors or individual effects for performance at 14, 21, 28, and 35 days. It is concluded that incubation of floor eggs, after standard sanitization, does not influence the hatch results and chick quality. Furthermore, it has been proven that the use of ceftiofur is unnecessary when there is correct management during broiler rearing.

The present study aimed to investigate the effects of different physical forms of feed and feeding programs on nutrient digestibility and performance of grower-finisher broilers under thermoneutrality or thermal stress. Three experiments were conducted using male broiler chickens (n = 720) aged 19-42 d. The design of two of the experiments was fully randomized in a 2 × 2 factorial arrangement with two forms of feed (mash and pellet) and two nutritional levels (13.19 MJ/kg and 194.8 g/kg CP - normal level and 13.61 MJ/kg and 210.3 g/kg CP - high level). The experiments took place in a climate-controlled room: Experiment 1 at thermoneutrality (21-23 °C and 58-60% relative humidity) for 24 h/day; Experiment 2 under thermal stress cycle (31-32 °C and 63-65% relative humidity), for 6h/day and thermoneutrality (21-23 °C, 58-60% relative humidity) for 18h/day. The nutrient digestibility and performance was analyzed. The design of the third experiment was fully randomized with two ambient condition treatments (thermoneutral and thermal stress) on heat production, caloric increment and net energy. Pellet feed obtained higher digestibility of dry matter, digestibility of crude protein, AME and AMEn (P 0.05) than mash feed for broilers reared in the thermoneutral environment. At the high nutritional level there was no effect of treatments on the coefficient of dry matter and crude protein (DCCP) (P 0.05), while the highest digestibility of AME and AMEn were obtained by the high nutritional level diet (P 0.05). Pellet feed had higher DCCP (P 0.05) than mash feed for broilers reared under cyclic heat stress. Broiler chickens under cyclic stress experienced increased caloric increment, rectal temperature and respiratory rate. The appropriate strategy to minimize these effects in both ambient conditions is to pellet feed.

Runting stunting syndrome (RSS) in commercial chickens has been reported worldwide, and although several studies have attempted to clarify the cause and describe the lesions, there are gaps in knowledge of the epidemiology, pathogenesis, and etiology. The study objective was to use commercial chicks naturally affected by RSS to describe the histologic changes of RSS in all segments of the small intestine in chicks of different ages and to identify viral gene sequences in affected chicks and their association with histologic lesions. Chicks lacking clinical signs but from the same houses and from unaffected houses were used as controls. The average weight of affected chicks was significantly lower than expected for their flocks. Macroscopically, the small intestines had paler serosa, with watery, mucoid, or foamy contents and poorly digested food. Histologic lesions were characterized by necrotic crypts, crypt dilation, and flattening of the crypt epithelium. Histomorphometry of the intestines revealed villous atrophy especially in the jejunum and ileum. Histologic changes in other organs were not observed. Random next-generation sequencing of total RNA extracted from formalin-fixed paraffin-embedded tissues detected avian nephritis virus, avian rotavirus, and picornavirus in jejunal segments from 7-day-old chicks. No viruses were detected in the jejunum of 1-day-old chicks. Detection of picornaviral reads was significantly associated ( P < .05) with histologic lesions of RSS. Sequence analysis of the picornavirus revealed genetic similarity with the genus Gallivirus. Using in situ hybridization for galliviral nucleic acid sequences, the signal was associated with crypt lesion severity, although signal was detected both in chicks with and without RSS.

The occurrence of antimicrobial resistance in microorganisms isolated from eggshells, especially Enterococcus, might serve as a parameter to assess the selection of bacteria due to the use of drugs in the diet of laying hens. In order to evaluate the frequency and the antimicrobial resistance profile of Enterococcus spp. isolated from the eggshells, 225 Hy-line laying hens were submitted to a 25-day long trial. The treatments were the following: hens fed ration without antimicrobials (control) and groups that received oxytetracycline (10 mg kg−1), doxycycline (20 mg kg−1), lincomycin (50 mg kg−1) and enrofloxacin (10 mg kg−1) in the ration for five days. Six replications were analyzed per treatment, composed of a pool of five eggs each. They were collected before treatment and on days 3, 6, 15 and 25, totaling 150 samples. Eggshells were submitted to counts of Enterococcus spp., which were identified by proteomic analyses. Antimicrobial resistance was determined by the disk-diffusion test. It was observed that 97.3% (n=146) of the samples were contaminated with Enterococcus spp. There were no differences (P>0.05) in the bacterial counts between treatments on the same day of evaluation. E. faecalis and E. faecium were the most frequent on the eggshells of all treatments. Multiresistance to the four classes of antimicrobials was also verified in the isolated bacteria. A total of 83% of the Enterococcus isolates showed resistance to neomycin, which was not administered to the hens, demonstrating an environmental problem. Thus, feeding laying hens with diets added with antimicrobials induces drug resistance in Enterococcus spp, isolated form the eggshells.

A avicultura de corte brasileira sustenta-se sobre a estrutura de governança híbrida estabelecida entre empresas integradoras e unidades de produção rural. Contudo, algumas empresas ainda investem na manutenção e aquisição de instalações próprias para criação das aves. Objetivou-se avaliar o desempenho zootécnico de frangos de corte de acordo com o gênero alojado e analisar o resultado econômico da atividade sob diferentes mecanismos de governança. Estudos de caso foram utilizados como procedimentos de pesquisa para avaliação da atividade em núcleos de criação da empresa integradora e de produtores rurais integrados. Dados primários sobre custos, receitas e indicadores zootécnicos foram coletados em 24 unidades de produção de aves pertencentes a uma empresa integradora e cinco produtores rurais integrados, localizados no estado de Minas Gerais. Foram utilizadas informações provenientes de 144 lotes de frangos de corte COBB® produzidos entre agosto de 2015 e agosto de 2016. Indicadores zootécnicos de lotes exclusivos para machos foram melhores que os observados para criação mista de aves e para lotes de fêmeas, respectivamente. Entretanto, na comparação dos resultados com os valores esperados para a linhagem, o potencial genético das aves poderia ter sido melhor aproveitado pelas unidades de produção rural. Independente do gênero das aves, análises econômicas indicaram que somente a criação de frangos de corte no modelo de integração foi capaz de conferir lucro econômico à atividade. Constatou-se que, para qualquer estrutura de governança avaliada, a criação de aves não se sustenta financeiramente sem receitas secundárias provenientes da venda de cama dos aviários.

The main objective of this study was to evaluate the effect of placement time on the performance of broiler chickens and the development of their gastrointestinal tract. Two methodologies for measuring broiler performance were compared, one considering day of pulling as the first day, the other considering day of placement as the first day. A total of 1,056 one-day old male Cobb® 500 broiler chicks were subjected to treatments of different placement times after pulling from the hatchery: 3, 24, 48, and 72 h. The studied traits were: feed intake, body weight, feed conversion, viability, and gastrointestinal tract development. When day of pulling was considered the first day, feed intake and body weight at 39 days decreased as placement time increased. However, when day of placement was considered the first day, fasting up to 72 h did not have any negative effect on broiler performance at 39 days post-placement. Placement time did not affect yolk sac utilization or liver weight. At nine days post-placement, weights of gizzard + proventriculus, pancreas, and small intestine increased with increasing placement time. At seven days of age, there was no effect of placement time on villus height or crypt depth. It is possible to place broiler chicks up to 72 h post-hatching with no negative effects when day of placement is considered the first day for evaluating broiler performance.

This study assessed the effects of breeder age, placement time and the use of a pre-placement feed (PPF) on yolk sac absorption, duodenum villus height and crypt depth and performance of male broiler chicks. A total of 1440 broiler chicks were randomly allocated to eight treatments. The study design was fully randomized in a 2 × 2 × 2 factorial scheme (breeder age × placement time × PPF). The factors were: broiler chicks from breeders of two ages (29 or 55 weeks), two placement times (24 or 48 h after pulling) and PPF or not of 2.5 g/chicks inside transport boxes. Yolk sac relative weight was determined from pulling to four days post-hatch; duodenum villus height and crypt depth were determined at pulling and at three and seven days of age; and performance was determined until 37 days. Six replications of two chicks for each treatment were used for yolk sac absorption, while eight replications of 15 measurements of one chick for each treatment were used for villus height and crypt depth. A total of 1440 broiler chicks were used (180 from each treatment) to determine performance. All experimental treatments were randomly assigned to six pens each with 30 chicks per pen-floor (12 birds/m²). Early access to feed stimulated yolk sac absorption until four days of age (P ≤ 0.05), and this effect was stronger for chicks from 29-week-old broiler breeders (P ≤ 0.05). On the other hand, placement within 48 h negatively impaired the development of duodenum villus and crypt until 7 days of age for chicks from young broiler breeders, but this negative effect could be reduced by the use of PPF (P ≤ 0.05). These results suggest that the use of PPF inside transport boxes is recommended for chicks from young broiler breeders that will be submitted to delayed feed access in order to improve gastrointestinal tract development, mainly that of the duodenum mucosa.

O objetivo desse estudo foi determinar o nível ideal de suplementação de manganês (Mn) para frangos de corte. Foram realizados dois experimentos, um avaliando uma fonte quelatada (aminoacídico) e o outro uma fonte inorgânica (óxido) que garanta melhor desempenho e qualidade óssea necessária, para suportar o processo de crescimento, pega, transporte e abate. O período experimental foi de um a 35 dias de idade das aves, onde foram utilizados 1260 frangos de corte machos da linhagem Cobb®. Os tratamentos foram definidos pela suplementação de 0, 35, 70, 105 mg de Mn/kg de ração na forma inorgânica ou quelatada do mineral. A ocorrência de lesões ou fraturas ósseas foi observada desde a apanha das aves até a linha de abate e não foi observada nenhuma incidência de lesões ósseas. As estimativas da exigência de Mn para frangos de corte para a máxima concentração desse micromineral e do Ca no fêmur foram, respectivamente, 57,36 mg de Mn/kg e 81,07 mg/kg de suplementação na forma inorgânica. Para os níveis de suplementação do Mn quelatado, a estimativa da exigência foi de 73,13 mg de Mn/kg para a máxima concentração de Ca no fêmur, não apresentando diferenças para a concentração de Mn nesse mesmo tecido ósseo. Os demais parâmetros de desempenho e qualidade óssea avaliada não apresentaram diferenças para ambas as fontes estudadas. Portanto, não há necessidade de suplementação de Mn em uma dieta a base de milho e farelo de soja, para frangos de corte.

A high-performance liquid chromatography with ultraviolet detection (HPLC-UV) method was validated for the study of bioactive amines in chicken meat. A gradient elution system with an ultraviolet detector was used after extraction with trichloroacetic acid and pre-column derivatization with dansyl chloride. Putrescine, cadaverine, histamine, tyramine, spermidine, and spermine standards were used for the evaluation of the following performance parameters: selectivity, linearity, precision, recovery, limits of detection, limits of quantification and ruggedness. The results indicated excellent selectivity, separation of all amines, a coefficient of determination greater than 0.99 and recovery from 92.25 to 102.25% at the concentration of 47.2mg.kg-1, with a limit of detection at 0.3mg.kg-1 and a limit of quantification at 0.9mg.kg-1 for all amines, with the exception of histamine, which exhibited the limit of quantification, of 1mg.kg-1. In conclusion, the performance parameters demonstrated adequacy of the method for the detection and quantification of bioactive amines in chicken meat. RESUMO Um método de cromatografia líquida de alta eficiência (CLAE) para pesquisa de aminas bioativas em carne de frango foi validado. Foi utilizado um sistema de gradiente de eluição com detector ultravioleta, após extração com ácido tricloroacético e derivação pré-coluna com cloreto de dansila. Os padrões de putrescina, cadaverina, histamina, tiramina, espermidina e espermina foram utilizados para avaliação dos seguintes parâmetros de desempenho: seletividade, linearidade, precisão, recuperação, limites de detecção, limites de quantificação e robustez. Os resultados mostraram excelente seletividade e separação de todas as aminas, coeficiente de determinação superior a 0,99, recuperação entre 92,25 e 105,25% na concentração 47,2mg.kg-1, limites de detecção de 0,3mg.kg-1 e limite de quantificação de 0,9mg.kg-1 para todas as aminas, com exceção da histamina, que apresentou o limite de quantificação mais alto, de 1mg.kg-1. Foi concluído que os parâmetros de desempenho demonstraram adequação do método para detecção e quantificação de aminas bioativas em carne de frango.

Com o objetivo de determinar valores de energia metabolizável aparente e de energia metabolizável aparente corrigida pelo balanço de nitrogênio de alimentos para frangos de corte, bem como avaliar os efeitos da correção da energia sobre seu desempenho, foram conduzidos dois experimentos: I) determinação da energia do milho, do farelo de soja, da farinha de carne e ossos, da farinha de vísceras e da farinha de penas, pelo método de coleta total de excretas, utilizando-se 450 pintos de corte com um dia de idade, distribuídos em delineamento inteiramente ao acaso, sendo seis tratamentos e cinco repetições; II) desempenho de 960 frangos de corte, distribuídos ao acaso, em cinco tratamentos e seis repetições. As aves que receberam os tratamentos A (matriz energética de acordo com Rostagno et al. (2011)) e E (energia sem correção com ajuste pela idade) apresentaram melhor desempenho, e as aves do tratamento E tiveram melhor conversão alimentar. Portanto, formulações com energia sem correção pelo balanço de nitrogênio e ajustadas pela idade são viáveis tanto sob o ponto de vista zootécnico, quanto econômico. Palavras-chave: aves, custo, desempenho, formulação, nutrição In order to determine apparent metabolizable energy and apparent metabolizable energy corrected by nitrogen balance of feed ingredients and to evaluate the effects of this correction on performance of broiler chickens, two experiments were conducted: I) energy determination of corn, soybean meal, meat and bone meal, poultry by-products meal and feather meal by total excreta collection method, using 450 chicks randomly distributed in 30 cages, with 6 treatments and 5 replications; II) performance of 960 broilers, distributed in a completely randomized design, with 5 treatments and 6 replications. Birds that received treatments A (energy matrix from literature) and E (energy without correction adjusted by age) showed better performance with the best feed cost, and treatment E had smaller feed conversion ratio. Therefore, the use of formulations based on metabolizable energy adjusted for age and without correction by nitrogen balance is feasible, both from a zootechnical and economic point of view. Keywords:costs, formulation, performance, nutrition, poultry

The broiler chick's gastrointestinal tract undergoes significant morphological and physiological changes during the first days after hatch. These changes occur mostly because birds switch from a diet based on fatty acids from the yolk sac to a diet based on carbohydrates, provided by commercial feeds, often formulated with corn and soya bean meal. In ovo feeding techniques enable the study of the early adaptation of the avian gastrointestinal tract, such as supplementation with carbohydrates during embryonic development. This procedure consists of inoculation into the amniotic fluid through a hole in the egg shell near the air-chamber during late embryonic growth. The hatching process requires large supply of energy to the muscles, and in ovo feeding has the objective of providing extra energy in order to avoid glycogen store reductions, which are needed during the first days after hatch. However, published reports have shown that in ovo manipulation can reduce incubation yield, mostly when applied during the beginning of embryonic development. The best results of in ovo feeding were found when supplementation was with carbohydrates.

The aim of the present study was to investigate the effects of reduced dietary protein levels on metabolism and performance in growing-finishing broilers under thermoneutral temperature or thermal stress. Two experiments were performed using male Cobb 500™ broilers (n = 720) aged, 22–42 d. For both experiments, the experimental design involved four treatments (220, 200, 180 and 160 g/kg CP), with six replicates of 15 birds each in a climate-controlled room; Experiment 1: 21–25 °C; 58–62 % relative humidity during 24 h/day and Experiment 2: 30–34 °C; 58–62 % relative humidity during 8 h/day and 16 h of thermoneutrality, (21–25 °C/ 58–62 % relative humidity). The diets were isocaloric (13.18 MJ/kg), following amino acid corrections. The analyzed variables were: protein digestibility; ether extract; dry matter; apparent metabolizable energy; nitrogen corrected apparent metabolizable energy; net energy and excreted nitrogen. In addition, performance and economic parameters were analyzed: relative body weight, feed intake, weight gain, feed conversation ratio, viability, European index of production and production costs. For both experiments, reduction from 220 to 160 g/kg CP impaired digestibility of protein and ether extract, decreasing the availability of net energy/bird. The amino acid correction used with 160 g/kg crude protein did not achieve the results for birds receiving 220 g/kg protein. However, the level of 200 g/kg crude protein in the diet is ideal for maximizing broiler performance in thermoneutral temperature and cyclic heat stress, besides providing lower nitrogen excretion in the excreta in relation to the diet of 220 g/kg CP.

Different sanitization methods were evaluated as alternatives to formaldehyde fumigation for the reduction of eggshell and yolk sac microbiological counts, improvement of eggshell quality, incubation parameters, and day-old chick quality. A total of 10,080 hatching eggs were collected from a 70-wk-old commercial broiler breeder flock and distributed in a completely randomized block design with seven treatments: fumigation with paraformaldehyde (5.03 g/m3/30 min), fumigation with ozone (5–15 ppm/30 min), ultraviolet light-C irradiation (8.09 mW/cm2; 120 s; UV-C), hydrogen peroxide spraying (3%; 0.69 mL/egg), peracetic acid spraying (0.3%; 0.69 mL/egg; PAA), water spraying (0.69 mL/egg; water control), and without disinfection (dry control—DC). Spraying eggs with PAA and UV-C significantly reduced aerobic bacteria plate counts compared to the DC group. In addition, eggs disinfected with PAA had lower Enterobacteriaceae counts than the DC and water control groups. Eggshell quality, incubation parameters, and microbiological counts for yolk sac did not differ (P > 0.05) among treatments. This study demonstrated the potential for the application of PAA and UV-C for eggshell disinfection instead of formaldehyde; however, an electronic microscopic evaluation of the eggshell is necessary to determine if these methods cause any damage to the cuticle.

Objetivou-se a avaliação dos efeitos dos níveis de suplementação de vitamina E na ração para frangos de corte sobre o desempenho na fase inicial (um a 21 dias de idade) e de crescimento (21 a 39 dias de idade). Os tratamentos foram definidos pelos níveis de suplementação de vitamina E (DL-α tocoferol). As quantidades adicionadas às rações foram: 10; 30; 50; 75 e 100mg de vitamina E para cada kg de ração. Na fase inicial (experimento I), o menor nível de suplementação de vitamina E mostrou-se superior aos demais, apresentando efeito significativo (P≤0,05) sobre o peso médio aos 21 dias de idade e ganho de peso de um a 21 dias de idade. Na fase de crescimento (experimento II), não houve efeito significativo (P>0,05) dos níveis de suplementação de vitamina E sobre as variáveis estudadas. O nível mínimo de suplementação de vitamina E testado (10mg/kg) é suficiente para atender às exigências dos frangos de corte machos sobre o desempenho. This study aimed to evaluate the effect of vitamin E supplementation on the performance of broiler chickens in the initial and growth phase, from one to 21 and 21 to 39 days of age, respectively. Five increasing levels of DL-α tocopherol supplementation (10, 30, 50, 75 and 100mg to each kg of diet) were added to the diet. In the initial phase (experiment I), the lowest vitamin E level was superior by presenting significant effect (P≤0.05) on body weight at 21 days of age and weight gain from one to 21 days old. In the growth phase (experiment II), there was no significant effect (P>0.05) of vitamin E supplementation on the variables studied. The minimum level of vitamin E supplementation tested is sufficient to attend the requirements of male broiler chickens.

This work aimed at evaluating the effects of 4 digestible Met+Cys levels on the diet of commercial layers and their influence on the productive performance, quality, and amino acid profile of eggs and economic viability of the activity. A total of 576 white Lohmann LSL-Lite layers was distributed into 6 replicates of 24 birds for each diet. The experimental design was completely randomized, with 4 treatments defined by levels evaluated in the feed (0.465, 0.540, 0.581, and 0.647%). The productive performance was measured for 30 weeks. The quality (34 and 50 wk old) and the amino acid profile of eggs (43 wk old) also were evaluated. A linear positive response was observed at higher Met+Cys levels for feed intake, number of eggs per housed bird, and digestible Met+Cys intake. Egg production, egg weight, egg mass, feed efficiency, and weight gain had their optimal values determined by the quadratic regression model at 0.638, 0.654, 0.647, 0.644, and 0.613% digestible Met+Cys, respectively. In the 34th wk, eggshell thickness decreased linearly at higher Met+Cys levels. In the 50th week, the optimal levels detected for eggshell thickness and percentage were 0.571 and 0.570% digestible Met+Cys, respectively. The percentages of proteins, branched-chain amino acids (leucine, isoleucine, and valine), histidine, and proline in eggs (albumen+yolk) showed a linear negative response in function of higher Met+Cys levels. Higher digestible Met+Cys levels (>0.630%) led to a good performance of layers, while lower Met+Cys levels improved the eggshell quality of layers in peak production. Optimal Met+Cys levels may change according to the price of the synthetic amino acid.

Due to the high demands and production costs of the poultry industry it is imperative to study alternatives to modify the practice of incubation in order to maximise productivity by ensuring the conditions necessary for the development of embryos of current strains. Such changes in the management of incubation cannot affect the quality of chicks and broiler performance during early growth. To achieve these goals, several factors that work together during artificial incubation should be considered, for example, the relative humidity and turning machine incubators. Some research has already been conducted to define the optimum for these factors. This article reviews the results of studies where relative humidity and use of turning systems in incubators and their impact on incubation yield and chick performance were examined.

Egg storage is a common and important practice in the poultry industry. Knowledge of the effects of storage on the egg, the embryo and incubation yield is important for planning incubation by hatcheries. Recommendations for storage environmental conditions depend mainly on the breeder age and storage time. Storage from seven days or more alters the characteristics of albumen, reduces incubation yield, increases incubation period and can damage embryonic development. When working with long storage periods, the adoption of management practices such as storing the egg with the thin tip down, egg turning during storage and pre-storage incubation should be considered to reduce the negative effects on the incubation yield.

The effects of different dietary lipids on the fatty acid profiles of eggs produced by 20- and 54-wk-old Dekalb laying hens were investigated. The 4 treatments were based on the lipid source added to the diet: soybean oil, sunflower oil, linseed oil, or control (no added oil). The experimental design was a simple random-sample design using a 4 × 2 factorial arrangement (4 treatments and 2 ages). The fatty acid composition of the yolks of eggs produced by the laying hens was analyzed. The fatty acid profiles found in the egg yolks were the same as those provided in each diet. Eggs laid by hens fed the diet containing soybean oil had a large amount of n-6 polyunsaturated fatty acids (PUFA), whereas eggs laid by hens fed the diet containing linseed oil had the highest percentage of n-3 PUFA. A decrease in PUFA deposition in egg yolks was observed as the laying hens got older. Eggs of hens fed the diet containing linseed oil presented an n-6:n-3 ratio of 2.01 in younger chickens and 2.17 in older ones. The trans fat percentages found in the egg yolks of all treatments were very low. It was concluded that the quantity of fatty acids present in the egg yolk may be altered according to the source of lipids in the diets; the addition of linseed oil to the ration of laying hens resulted in the production of n-3-enriched eggs and excellent n-6:n-3 ratios, and the egg yolks had insignificant amounts of trans fat, irrespective of the different lipid sources added to the diets or the age of the chickens.

O experimento foi conduzido em delineamento inteiramente ao acaso, para avaliar os efeitos da redução de proteína bruta (PB) com suplementação de aminoácidos essenciais sobre o desempenho e características de carcaça de frangos de corte machos da linhagem Ross, na fase de 21 a 42 dias de idade. Foram utilizados 720 frangos, distribuídos em 4 tratamentos e seis repetições com 30 aves cada. Os níveis de proteína bruta utilizados foram 21; 19 e 17 e 15% de PB. A redução de proteína levou a um aumento linear dos teores de gordura e matéria seca. Houve ainda efeito quadrático dos níveis de proteína bruta, sendo para máximo ganho de peso, peso aos 42 dias e consumo de dieta os níveis de 19,28; 19,35 e 16,75% de PB, respectivamente. Houve efeito quadrático sobre o rendimento de peito, estimando máximo rendimento para frangos alimentados com dietas contendo 18,28% de PB. A completely randomized experimental design was carried out to evaluate the effects of crude protein (CP) reduction of diets with essential amino acids supplementation on performance and body composition of male broiler chickens from 21 to 42 days of age. A total of seven hundred twenty broiler chickens were used. The birds were allotted in four treatments and six replicates of thirty birds each. The diet CP levels were 21, 19, 17 and 15%. The reduction of protein led to a linear increase in fat and dry matter. There was also a quadratic effect of the CP levels; for maximum weight gain; weight at 42 days and final weight and feed intake. The maximum performance of these parameters were estimated for broilers fed 19.28; 19.35 and16.75% CP diet, respectively. There was a quadratic effect of CP level on breast yield, the maximum performance estimated for broiler fed 18.28% CP diet.

The reaction of free radicals with polyunsaturated fatty acids (PUFAs) initiates a chain-reaction process known as lipid peroxidation in living systems and oxidative rancidity in foods. PUFAs are m...

Os efeitos de fontes de lipídios na dieta de poedeiras sobre o desempenho produtivo e a qualidade do ovo foram verificados em dois experimentos. Foram utilizados quatro tratamentos, definidos de acordo com a fonte lipídica adicionada nas rações: óleo de soja, óleo de girassol, óleo de linhaça e ração controle (sem adição de óleo). Os experimentos foram realizados com poedeiras de 20 e 54 semanas de idade, respectivamente, com duração de oito semanas. Avaliaram-se os parâmetros produtivos - consumo de ração, conversão alimentar, produção e peso dos ovos - e de qualidade do ovo - porcentagens de gema, albúmen e casca, sólidos da gema, unidades Haugh, pH do albúmen, e cor da gema. Somente o peso do ovo de poedeiras jovens foi afetado pela inclusão de óleos vegetais na ração. Esses ovos apresentaram maior peso e maior porcentagem de gema que os produzidos pelas poedeiras jovens alimentadas com ração-controle. Concluiu-se que a utilização de diferentes fontes de lipídios na ração de poedeiras não altera o desempenho produtivo e a qualidade interna dos ovos, com exceção do peso do ovo de poedeiras novas, que aumenta com a utilização de óleos vegetais.

The interference of low or high maternal antibodies titers on the attenuated infectious bursal disease (IBD) virus (IBDV) vaccine infection and its effects on the performance of broilers vaccinated at the 18th day of incubation (in ovo), at one day of age (subcutaneously-SC), or at 15 days of age (drinking water-DW) were investigated. After a series of three live vaccinations, breeders were given or not an IBD oil emulsion vaccine (IBD-OEV) prior to sexual maturity. At day 18 of incubation (in ovo), a commercial vaccine containing HVT and an intermediate IBDV strain or the single HVT vaccine was given. An intermediate IBDV vaccine was given SC at one day of age, or at 15 days of age via DW. The progeny of unvaccinated breeders presented higher neutralizing IBDVspecific antibody (IBDVab) titers at 25 and 40 days of age than those of the progeny of IBD-OEV breeders (p

Verificou-se a qualidade interna de ovos de consumo armazenados sob diferentes condições, utilizando-se 768 ovos, provenientes de galinhas Hy-line com 40 semanas de idade. Os tratamentos foram dispostos no delineamento inteiramente casualizado em arranjo fatorial 2x4x8 (ovos embalados em filme plástico e não embalados), quatro períodos de estocagem em temperatura ambiente (zero, cinco, 10 e 15 dias) e oito períodos de armazenamento sob refrigeração (zero, cinco, 10, 15, 20, 25, 30 e 35 dias). Foram avaliados os valores das Unidades Haugh (UH) e os de pH do albúmem (pH). Os valores de UH diminuíram com a estocagem, e houve uma queda mais acentuada nos ovos que permaneceram em temperatura ambiente. A embalagem das bandejas de ovos mostrou-se eficaz na preservação da qualidade interna dos ovos, pois os valores de UH mantiveram-se altos por um maior período de estocagem. Os índices de pH aumentaram com o período de armazenamento dos ovos (P

Avaliaram-se os efeitos dos programas de luz 23L:1E (23L); crescente (CRES); 16L:8E (16L) e luz natural (NAT) sobre o desempenho, rendimento de carcaça e resposta imunológica de frangos de corte machos da linhagem Cobb-500. O período de criação foi de um a 45 dias de idade, e os tratamentos foram definidos de acordo com os programas de luz. O delineamento experimental foi o inteiramente ao acaso com quatro tratamentos e seis repetições de 35 aves cada. As aves submetidas ao programa de luz CRES apresentaram maior peso vivo em relação aos demais tratamentos (P0,05). A viabilidade das aves do tratamento NAT foi maior em relação às aves do tratamento 23L (P0,05). A conversão alimentar e o rendimento de carcaça não foram influenciados pelos tratamentos (P>0,05). As aves do tratamento 23L apresentaram maior rendimento de peito quando comparado aos demais tratamentos (P0,05).

Compararam-se os efeitos da forma física da ração sobre a digestibilidade de nutrientes e o desempenho de frangos de corte. No primeiro experimento foram utilizadas 480 aves (machos) da linhagem Ross-308, de 1 a 42 dias de idade. O delineamento experimental foi inteiramente ao acaso com três tratamentos (farelada, granulada e expandida-granulada), com oito repetições de 20 aves. No segundo, utilizaram-se 900 aves da mesma linhagem, sexo e período de criação segundo o mesmo delineamento experimental, mas com 10 repetições de 30 aves cada. O coeficiente de metabolização da matéria seca não foi afetado pelos tratamentos. A proteína metabolizável foi maior na ração expandida granulada do que a farelada (P

Avaliaram-se os efeitos dos níveis de ácido linoléico na dieta de matrizes pesadas, de 27 a 40 semanas de idade, sobre o peso e composição dos ovos, porcentagem de eclosão, peso do pinto, porcentagem de saco vitelino em relação ao peso do pinto e composição de ácidos graxos da gema. Os tratamentos foram definidos pelo nível de ácido linoléico na dieta. O peso dos ovos e a composição de ácidos linoléico na gema foram mais altos com a inclusão de 1,93% de ácido linoléico que a de 1,48% (59,5g vs 59,0g e 19,5% vs 15,5%, respectivamente). Não houve diferença entre os tratamentos quanto às porcentagens de gema, albúmen, casca, saco vitelino, eclosão e peso do pinto.

Carbadox (CBX) and olaquindox (OLA) were used in poultry and swine feed for growth promotion, to improve feed efficiency and increase the rate of weight gain. However, the use of these agents in feedingstuffs was prohibited because of concerns about their toxicity. Regulatory laboratories are required to have suitably validated analytical methods to ensure compliance with the ban. A quantitative and confirmatory method for determining the presence of CBX and OLA in poultry and swine feed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) was developed, optimized, and validated. The analytes extraction was performed with a mixture of water and acetonitrile (1:1v/v) and cleanup with hexane and C18 (dispersive phase). The method was evaluated by the following parameters: specificity, linearity, matrix effect, decision limits (CCα), detection capability (CCβ), accuracy, precision, limits of detection (LoD), limits of quantification (LoQ) and measurement uncertainty. The validated method presented a broad linear study range and no significant matrix effect. The limit of detection (LoD) was defined at 9 μg kg(-1) for CBX and 80 μg kg(-1) for OLA, and the limit of quantification (LoQ) was defined at 12 μg kg(-1) and 110 μg kg(-1) for CBX and OLA, respectively. The accuracy of the method was adequate for CBX and OLA. The recovery values found in the repeatability conditions were 99.41% for CBX and 104.62% for OLA. Under intralaboratory reproducibility conditions, the values were 98.63% for CBX and 95.07% for OLA. It was concluded that the performance parameters demonstrated total method adequacy for the detection and quantification of CBX and OLA in poultry and swine feedingstuffs.

The terms "fat" and "oil" refer to triglycerides of several profiles of fatty acids. Fatty acids that are not bound to other organic components as glycerol are the so-called free fatty acids. Lipids constitute the main energetic source for animals and they have the highest caloric value among all the nutrients. Linoleic acid is the only fatty acid whose dietetic requirement has been demonstrated. Besides supplying energy, the addition of fat to animal diets improves the absorption of fat-soluble vitamins, decreases pulverulence, increases diet palatability, and the efficiency of utilization of the consumed energy. Furthermore, it reduces the rate of food passage through the gastrointestinal tract, which allows a better absorption of all nutrients present in the diet. The energetic value of oils and fats depend on the following: the length of the carbonic chain, the number of double bonds, the presence or absence of ester bonds (triglycerides or free fatty acids), the specific arrangements of the saturated and unsaturated fatty acids on the glycerol backbone, the composition of the free fatty acid, the composition of the diet, the quantity and the type of the triglycerides supplemented in the diet, the intestinal flora, the sex and the age of the birds. In birds, body fat composition is similar to the composition of the fat from the diet. The apparent digestibility of unsaturated fats is high in the first days of life of birds, whereas apparent digestibility of saturated fats is low. The quantity of oils or fats is assessed by the following methods: titration, moisture, impurities, unsaponifiable, saponification value, percentage of fat, percentage of free fatty acids/acidity and the profile of fatty acids. The methods initial peroxide value, active oxygen method, osi, iodine value, and analysis of the thiobarbituric acid (TBARS) are specific to evaluate the oxidative stability. Considering diets with the same nutritive values, birds fed with rations containing oil present better performance than birds fed no oil. Moreover, the use of oil or fat in diets for broilers may change both the composition and the quality of the carcass.

The depletion times of the anticoccidial nicarbazin administered individually and of nicarbazin and narasin administered in combination were evaluated by determining the presence and levels of 4,4'-dinitrocarbanilide (DNC), the marker residue for nicarbazin, and narasin residues in the muscle tissues of broiler chickens subjected to a pharmacological treatment. A high-performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method was used. The results showed the presence of all anticoccidial residues; however, the DNC levels were higher when the nicarbazin was administered individually than when it was used in association with narasin throughout the experimental period. After six days of withdrawal, the DNC level following nicarbazin administration alone was lower than the maximum residue level (MRL) of 200 μg kg-1. However, when the nicarbazin was co-administered with narasin, the concentrations of DNC were lower than the MRL after four days of withdrawal. These results may be justified because the dosage of nicarbazin, when administrated individually, is greater than when it is used in combination with narasin. The levels of narasin were lower than the MRL of 15 μg kg-1 throughout the evaluation period. It was concluded that nicarbazin is rapidly metabolized from the broiler muscles up to six days of withdrawal since the DNC levels were lower than the maximum residue level (MRL) and the concentrations of narasin were lower than the MRL throughout the evaluation period.

The objective of this study was to evaluate the correlation between the levels of bioactive amines and the microbiological quality of liquid pasteurized egg stored under refrigeration. Pasteurized whole egg liquid was obtained from 2 types of different raw materials, fresh eggs, and commercial fertile eggs. They were stored under refrigeration over a period of 21 d. The treatments were arranged in a completely randomized split plot, with the plots being the 2 types of liquid pasteurized egg, and the subplots being the 4 storage periods (1, 7, 14, and 21 d). The storage period did not contribute to the increase (P0.05) of contamination by mesophilic aerobic microorganisms and total coliforms in commercial liquid pasteurized egg. However, for fertile eggs, the storage period led to an increase (P0.05) in the numbers of microorganisms. Levels of the amines putrescine, cadaverine, and tyramine were detected only in fertile liquid pasteurized egg, and the storage period contributed to the increase (P0.05) in the levels of these amines. There was a high correlation between total coliform most probable number and cadaverine levels, and a moderate correlation between the numbers of aerobic mesophilic microorganisms and tyramine levels. It was concluded that the most contaminated liquid pasteurized eggs were the fertile liquid pasteurized eggs and this caused the highest levels of bioactive amines in them compared with all the eggs that had been subjected to pasteurization and refrigerated storage.

The depletion times of enrofloxacin and its metabolite ciprofloxacin as well as sulfaquinoxaline and oxytetracycline were evaluated in broiler chickens that had been subjected to pharmacological treatment. The presence and residue levels of these drugs in muscle tissue were evaluated using an ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) method that was validated in this work. The results showed the presence of all antimicrobial residues; however, the presence of residues at concentrations higher than the drugs' maximum residue limit (MRL) of 100 μg kg-1 was found only during the treatment period for oxytetracycline and until two days after discontinuation of the medication for enrofloxacin, ciprofloxacin and sulfaquinoxaline. It was concluded that the residues of all antimicrobials were rapidly metabolized from the broiler muscles; after four days of withdrawal, the levels were lower than the limit of quantification (LOQ) of the method for the studied analytes.

The physicochemical and microbiological qualities of commercial eggs produced by layer hens of different ages (approximately 30 and 60 wk old) were submitted to storage under room temperature or re- frigeration for 28 d. A total of 600 eggs were subject- ed to microbiological analyses of their inner contents and another 600 to a determination of Haugh units (HU) and bioactive amine content. A decrease in the quality of the inner contents of the eggs was observed during the experiment, mainly in the eggs from the 60-wk-old layers, which presented the worst HU values when stored at room temperature (P < 0.05). Micro- biological analyses showed an absence of Salmonella spp., Staphylococcus aureus, and coliforms, either to- tal or thermal-tolerant; however, low counts of other Staphylococcus species, Enterobacter spp., Pseudomonas spp., mesophilic aerobic bacteria, and fungi were also recorded. The chromatographic analysis of bioactive amines detected the presence of phenylethylamine in all albumens (38.0 mg/kg) and spermidine in the yolks (1.02 mg/kg). It was concluded that the age of the hens and the time and temperature of storage influenced the quality parameters of the eggs (P < 0.05). Further- more, despite the low levels of microbial contamination found, phenylethylamine was detected in the albumen. It was not possible to establish index of quality of eggs using bioactive amines present in the yolk and albumen of eggs.