Efficacy of the phytogenic feed additive oregano essential oil (OEO) (Origanum vulgare L.) was assessed as an alternative to an antibiotic as a growth promoter (AGP) in broiler diets. Three hundred male broiler chicks were assigned to five treatments, which consisted of diets with different levels of OEO (300, 600, and 900 mg/kg of diet), a negative control, and a positive control. Broiler performance was evaluated from 1 to 21 and 1 to 39 days old. From 1 to 39 days old, the broilers of the negative control group presented lower feed intake than those fed OEO300. No significant effect was observed on weight gain. The greatest feed conversion ratio occurred in the positive control group. Broilers treated with OEO300 had greater carcass yield than those in the positive control group. The haemogram, leukogram, and heterophil/lymphocyte ratio were positively influenced by OEO300. Red blood cell and leukocyte counts increased in a dose-dependent manner in broilers fed OEO-supplemented diets, while broilers in the positive control group had the lowest levels of haematocrit, mean corpuscular haemoglobin concentration, and plasma protein. Differential leukometry revealed lymphocyte numbers were increased with OEO treatment and reduced in the positive control group. For hepatic and renal metabolism, the broilers in the positive control group exhibited the greatest serum activities of aspartate aminotransferase, alanine aminotransferase, gamma-glutamyl transferase, and alkaline phosphatase. Although more studies on its efficacy are needed, OEO at 300 mg/kg may be used as a phytogenic additive in broiler diets, especially those without AGP.

RESUMO Objetivou-se avaliar as características dos tibiotarsos de frangos de corte fêmeas. As variáveis analisadas foram os pesos in natura, secos e desengordurados, o comprimento, os diâmetros, a resistência óssea, o índice de Seedor (IS), os percentuais de proteínas colagenosas (PC), as proteínas não colagenosas (PNC), os minerais (cálcio, fósforo, potássio e sódio) e as cinzas. Foram utilizadas 648 aves, da marca comercial Cobb®, em um delineamento em blocos ao acaso, com seis tratamentos e seis repetições, com 18 aves por unidade experimental. Os tratamentos consistiram na suplementação de 0,00; 0,50; 1,00; 1,50; 2,00 e 2,50 μg de 1,25-dihidroxivitamina-D3 (1,25(OH)2D3)/kg de ração. Aos 21 e 35 dias de idade, as aves foram pesadas e uma ave por unidade experimental (UE) com o peso médio da UE foi eutanasiada para a obtenção dos tibiotarsos e subsequente análise dos parâmetros ósseos. As variáveis métricas, bem como a composição orgânica (PC), a densidade (IS) e a resistência à quebra dos ossos das aves, não foram influenciadas pelos tratamentos. No recebimento de 2,50 µg de 1,25(OH)2D3/kg de ração, observou-se maior retenção mineral (cinzas) nos ossos das aves aos 35 dias de idade.

ABSTRACT This study aimed to evaluate the characteristics of tibiotarsus of female broilers. The variables analyzed were the weights in natura, dry and degreased, length, diameter, bone strength, Seedor index, percentage of collagenous protein (CP), non-collagenous proteins (NCP), minerals (calcium, phosphorus, potassium and sodium), and ash. Six hundred forty-eight, Cobb® birds were used, a design of randomized blocks with six treatments and six replicates of 18 birds each. The treatments consisted of supplementation of 0.00; 0.50; 1.00; 1.50; 2.00 to 2.50 µg of 1,25-dihydroxyvitamin-D3 (1,25(OH)2D3)/kg of ration. At 21 and 35 days of age the birds were weighed and a unit/experimental unit (EU) with the EU average weight was euthanized to obtain the tibiotarsos and subsequent analysis of the bone parameters. The metric variables, as well as the organic composition (CP), density (IS) and resistance to breakage of the bones of the birds were not affected by treatments. Upon reception of 2.50 µg of 1,25(OH)2D3/kg ration, there was a higher mineral retention (ashes) in the bones of female broilers at 35 days of age.

Os efeitos da parede celular de Saccharomyces cerevisiae (PCSc) na dieta para frangos foram avaliados com base nos tratamentos: dieta referência com avilamicina (AV); dieta referência (DR); DR com 0,1% de PCSc (PCSc0,1); DR com 0,2% de PCSc (PCSc0,2); DR com 0,3% de PCSc (PCSc0,3). O delineamento foi o de blocos ao acaso, com cinco tratamentos e seis repetições de 10 aves, totalizando 300 frangos, machos. No período de nove a 21 dias de idade, o tratamento PCSc0,3 influenciou negativamente no ganho de peso (631g), e no período de 34 a 39 dias, o tratamento PCSc0,1 proporcionou melhor ganho de peso (461g) em relação ao tratamento com o antimicrobiano. O maior peso vivo ao abate, 2571g, foi obtido no tratamento PCSc0,1. Os pesos absolutos de sobrecoxa e coxa+sobrecoxa foram maiores nos tratamentos PCSc0,1 (290g e 560g) e PCSc0,2 (292g e 561g) e menores no tratamento PCSc0,3 (263g e 515g). Não houve influência na metabolizabilidade da ração e na contagem total de coliformes totais no íleo. Dietas com inclusão de até 0,2% de PCSc resultaram em índices produtivos adequados, podendo ser utilizadas como aditivo em dietas livres de antimicrobiano melhorador de desempenho sem o comprometimento do desempenho, características de carcaça, metabolizabilidade da ração e da contagem total de coliformes totais do íleo.

The effects of the yeast cell wall (Saccharomyces cerevisiae) (CWSc) in the diet of broiler chickens were evaluated through the following treatments: reference diet with avilamicin (AV); reference diet (RD); RD with 0.1% CWSc (CWSc0,1); RD with 0.2% CWSc (CWSc0,2); RD with 0.3% CWSc (CWSc0,3). The study design was randomized blocks, with five treatments and six replicates of 10 birds, totaling 300 male broilers. In the period from 9 to 21 days treatment CWSc0.3 had a negative influence on weight gain (631g) and from 34 to 39 days CWSc0.1 provided better weight gain (461g) compared to the treatment with the antimicrobial. The highest live weight value at slaughter, 2,571 grams, was obtained in treatment CWSc0.1. The absolute weights of drumstick and thigh+drumstick were higher in treatments CWSc0.1 (290g and 560g) and CWSc0.2 (292g and 561g) and were lower for CWSc0.3 (263g and 515g). There was no influence of the treatments on both the metabolizability and the total count of coliforms in the ileum. Diets until 0.2% of PCSc inclusion resulted in correct productive rates and they can be used as a ration growth promoter additive in antimicrobial free diets without damage on performance, carcass characteristics, organ weight, metabolizability of the diets and total coliform count in the ileum.

Determinou-se a composição de partes da carcaça - pescoço, dorso e pés de aves -, e sua digestibilidade, usadas para cães nas formas crua e cozida. Os animais, pesados antes e depois do período experimental, foram alimentados uma vez ao dia, com livre acesso ao alimento por uma hora. Cada animal recebeu aproximadamente 50g alimento/kg de peso. As fezes, coletadas diariamente, foram pesadas e congeladas até a realização das análises bromatológicas. Os pés apresentaram os maiores valores de proteína bruta (PB) e matéria mineral (MM), o pescoço, o maior valor de energia bruta (EB), e o dorso, os de matéria seca (MS), matéria orgânica (MO) e extrato etéreo (EE). O cozimento não alterou a composição dos alimentos, entretanto os alimentos cozidos apresentaram teores menores em PB e maiores em EE. Os coeficientes de digestibilidade da MO e da PB do pescoço aumentaram significativamente quando este foi cozido, e os valores de energia metabolizável (EM) e energia digestível (ED) diminuíram. O cozimento do dorso resultou em redução de EM e ED. Os coeficientes de digestibilidade da MS, MO e PB e a ED e EM do pé foram significativamente maiores para os pés cozidos.

In order to use an ingredient to formulate dog foods, it is ideal to the industry to know its properties including the digestibility. So, this work studied the chemical composition and the digestibility of chicken parts used to feed dogs, since they are used frequently by the dog food industry. The ingredients were raw and cooked neck, back, and feet. The animals were weighted before and after the experimental period and food was served once a day. The food was weighted before and after being served. Each animal consumed approximately 50g food/kg body weight. The feces were collected daily and freezed as well as the food until the bromatological analyses procedures. The feet had the highest values for crude protein (CP) and mineral content (MC); while the back, the highest values for dry matter (DM), organic matter (OM), and fat. Cooking had no significant effect on chemical composition of the ingredients. Considering the digestibility coefficient, OM and CP of neck had a significant increase when it was used in the cooked form; but, the metabolizable energy (ME) and the digestible energy (DE) values considerably decreased. For the back, the heat treatment resulted in a significant reduction of ME and DE and the digestibility coefficients of DM, OM, and CP, and ME, and DE of the feet were higher using the same treatment.