Effect of lipid sources and inclusion levels in diets for broiler chickens / Efeito de fontes lipídicas e níveis de inclusão em dietas para frangos de corte

This research aimed to evaluate the interactions and effects of 2 and 4% addition levels of poultry slaughterhouse fat (chicken tallow) and soybean oil in diets for broiler chickens. Two experiments were carried out using one-day-old male Cobb chicks in an entirely random design with a 2x2 factorial scheme. In the first experiment, 560 chicks were used to evaluate performance and carcass characteristics. In the second experiment, 100 chicks were used to determine the nutrient digestibility, dietary energy utilization and the lipase and amylase pancreatic activity. There was no interaction between the fat sources and the addition levels for any of the analyzed variables, except for the digestibility coefficient of dry matter (DCDM), which was higher in diets added with 2% soybean oil when compared to chicken tallow. The addition of 4% fat in the diet, regardless of fat source, improved the digestibility coefficient of ethereal extract (DCEE) and increased weight gain and feed intake. Moreover, in the initial phase, the addition of 4% fat to the diet increased lipase activity when compared to diets with 2% addition, and a positive correlation between DCEE and pancreatic lipase activity was observed. In conclusion, there is no interaction between fat sources and addition levels, except for DCDM. Carcass characteristics are not influenced by any of the studied factors. The addition of 4% fat increases pancreatic lipase activity and improves DCEE, resulting in greater weight gain, regardless of the tested fat source, making chicken tallow a great alternative to soybean oil.(AU)

O objetivo deste trabalho foi avaliar as interações e os efeitos da utilização de gordura de abatedouro avícola (gordura de frango) e de óleo de soja com níveis de inclusão de 2 e 4% em dietas para frangos de corte. Foram conduzidos dois experimentos com pintos de corte de um dia de idade, machos, da linhagem Cobb, alojados num delineamento inteiramente ao acaso em esquema fatorial 2x2. No primeiro experimento utilizaram-se 560 aves para avaliar o desempenho e as características de carcaça. No segundo experimento foram alojadas 100 aves para determinar o aproveitamento dos nutrientes e da energia da dieta, e também a atividade de lipase e amilase pancreática. Não houve interações entre as fontes lipídicas e os níveis de inclusão para nenhuma das variáveis analisadas, com exceção do coeficiente de metabolizabilidade da matéria seca (CMMS), que foi maior nas dietas com inclusão de 2% de óleo de soja em relação à gordura de frango. A inclusão de 4% de lipídios na dieta, independente da fonte lipídica, melhorou o coeficiente de metabolizabilidade do extrato etéreo (CMEE) e aumentou o ganho de peso e o consumo de ração das aves. Ainda, na fase inicial, a adição de 4% de lipídios na dieta aumentou a atividade de lipase em relação às dietas com inclusões de 2%, observando-se uma correlação positiva entre o CMEE e a atividade de lipase pancreática. Como conclusão, não há interação entre as fontes lipídicas e os níveis de inclusão estudados, com ressalva para o CMMS. As características de carcaça não são influenciadas por nenhum dos fatores estudados. A adição de 4% de lipídio aumenta a atividade de lipase pancreática e melhora o CMEE, refletindo em maior ganho de peso das aves, indiferentemente da fonte lipídica testada, o que torna a gordura de frango uma boa alternativa ao óleo de soja.(AU)

Isotopic traceability in body tissues and in different breeding periods of broilers / Rastreabilidade isotópica em tecidos corporais e em diferentes períodos de criação de frangos de corte

The inclusion of poultry viscera meal (VM) in broiler diets to possibly replace it with strictly vegetable diet (VE) and vice-versa, using the technique of carbon and nitrogen stable isotopes in different tissues was traced. One hundred ninety-two one-day-old chicks that had been distributed randomly were used in twelve experimental treatments with four replications of four chicks each. The treatments consisted of vegetable diet (VG) for diets containing FV going after a certain age or the reverse, in which the birds began feeding VM on diet and then switched to VE diet. At 42 days of age, samples of pectoral muscle (Pectoralis major), keel and tibia were collected, with later determination of isotopic ratios (13C/12C and 15N/14N). The stable isotopes technique couldn't trace the use of VM in feeding broilers when this ingredient was part of broiler diets only in the first seven, 14 or 21 days of age. However, this technique can be applied to younger poultry that have been sampled before a possible change in diet, since they can have the isotopic signature of feeding stabilized around two weeks of age.(AU)

Rastrearam-se a inclusão de farinha de vísceras de aves (FV) em dietas de frangos por ocasião de eventual substituição de dieta contendo FV por dieta estritamente vegetal, e vice-versa, por isótopos estáveis de carbono e de nitrogênio. Foram distribuídos aleatoriamente 192 pintos de um dia de idade, em 12 tratamentos com quatro repetições de quatro aves. Os tratamentos constituíam-se de dieta de vegetais (VG) passando para dietas contendo FV, após certa idade, ou o inverso, em que as aves começaram se alimentando de dieta FV e depois passaram para dieta VG. Aos 42 dias de idade, foram coletadas amostras de músculo peitoral (Pectoralis major), quilha e tíbia, para determinação das razões isotópicas (13C/12C e 15N/14N). A técnica dos isótopos estáveis somente não foi capaz de rastrear a utilização de FV na alimentação de frangos de corte, quando esse ingrediente fez parte da dieta das aves apenas nos primeiros sete, 14 ou 21 dias de idade. Entretanto, há a possibilidade da aplicação dessa técnica em aves mais jovens, amostradas antes de eventual mudança de dieta, pois elas podem ter a assinatura isotópica da alimentação estabilizada em torno de duas semanas de idade.(AU)

Effect of dietary organic selenium and zinc on the internal egg quality of quail eggs for different periods and under different temperatures

The objective of this study was to evaluate the internal quality of eggs of Japanese quails fed diets supplemented with chelated selenium and zinc. The experiment was carried out for 120 days, and 144 birds were divided in random blocks into four treatments (control; 0.3 ppm Se; 60 ppm Zn and 0.3 ppm Se + 60 ppm Zn). Ten, 14, 18, and 22 weeks after the beginning of lay, eggs were collected and stored under two different temperatures (environmental temperature or refrigeration) and for 10, 20, and 30 days. Eggs were analyzed for: Haugh units (HU), albumen height (AH), yolk index (YI), and albumen index (AI). Parameters were only statistically influenced by the interaction between dietary treatment and storage time. It was concluded that the addition of organic Se and Zn influenced internal egg quality when eggs were stored up to 20 days, independently of storage temperature, suggesting that the combined supplementation of organic Se and Zn improve internal egg quality and extend egg shelf life.(AU)

Effect of dietary organic selenium and zinc on the internal egg quality of quail eggs for different periods and under different temperatures

The objective of this study was to evaluate the internal quality of eggs of Japanese quails fed diets supplemented with chelated selenium and zinc. The experiment was carried out for 120 days, and 144 birds were divided in random blocks into four treatments (control; 0.3 ppm Se; 60 ppm Zn and 0.3 ppm Se + 60 ppm Zn). Ten, 14, 18, and 22 weeks after the beginning of lay, eggs were collected and stored under two different temperatures (environmental temperature or refrigeration) and for 10, 20, and 30 days. Eggs were analyzed for: Haugh units (HU), albumen height (AH), yolk index (YI), and albumen index (AI). Parameters were only statistically influenced by the interaction between dietary treatment and storage time. It was concluded that the addition of organic Se and Zn influenced internal egg quality when eggs were stored up to 20 days, independently of storage temperature, suggesting that the combined supplementation of organic Se and Zn improve internal egg quality and extend egg shelf life.

Emulsifier in broiler diets containing different fat sources

This present study aimed at evaluating the effect of the addition of an emulsifier to diets containing soybean oil, poultry fat or their blend, on the performance, carcass traits, serum lipid levels, pancreatic lipase concentration and nutrient digestibility of broilers. A randomized block design was applied using a 3 x 2 factorial arrangement, with three fat sources (soybean oil, poultry fat, and a blend of 50% soybean oil and 50% poultry fat) and the addition or not of an emulsifier. In experiment I, broiler performance, carcass traits, serum cholesterol, HDL, and triglyceride levels, and pancreatic lipase activity in 42-day-old broilers were evaluated. In experiment II, dry matter (DM), ether extract (EE), crude protein (CP) and crude fiber (CF) coefficients of digestibility were analyzed. Broilers fed the diet containing soybean oil and emulsifier presented higher body weight, weight gain and better feed conversion ratio. When birds were fed poultry fat and the fat blend (soybean oil and poultry fat) and the emulsifier was added to the diets, pancreatic lipase concentration increased. It was concluded that the use of soybean oil, poultry fat and their blend does no in the diet does not influence the performance, carcass traits, or serum cholesterol, HDL and triglyceride levels of 42-day-old broilers. The addition of emulsifiers to diets containing poultry fat improves ether extract digestibility and increases the production and secretion of pancreatic lipase.(AU)

Emulsifier in broiler diets containing different fat sources

This present study aimed at evaluating the effect of the addition of an emulsifier to diets containing soybean oil, poultry fat or their blend, on the performance, carcass traits, serum lipid levels, pancreatic lipase concentration and nutrient digestibility of broilers. A randomized block design was applied using a 3 x 2 factorial arrangement, with three fat sources (soybean oil, poultry fat, and a blend of 50% soybean oil and 50% poultry fat) and the addition or not of an emulsifier. In experiment I, broiler performance, carcass traits, serum cholesterol, HDL, and triglyceride levels, and pancreatic lipase activity in 42-day-old broilers were evaluated. In experiment II, dry matter (DM), ether extract (EE), crude protein (CP) and crude fiber (CF) coefficients of digestibility were analyzed. Broilers fed the diet containing soybean oil and emulsifier presented higher body weight, weight gain and better feed conversion ratio. When birds were fed poultry fat and the fat blend (soybean oil and poultry fat) and the emulsifier was added to the diets, pancreatic lipase concentration increased. It was concluded that the use of soybean oil, poultry fat and their blend does no in the diet does not influence the performance, carcass traits, or serum cholesterol, HDL and triglyceride levels of 42-day-old broilers. The addition of emulsifiers to diets containing poultry fat improves ether extract digestibility and increases the production and secretion of pancreatic lipase.