Composição química e digestibilidade de partes e subprodutos de aves nas formas crua e cozida para cães

Abstract

Two experiments were conducted to determine the composition and the digestibility of chicken by products by dogs. The ingredients were evaluated raw and cooked. The ingredients studied were chicken head, neck, back, feet, liver and residue of mechanically separated chicken meat (MSM). In the first experiment neck, back and feet were evaluated and in the second one head, MSM and liver. Each ingredient was offered raw or cooked to measure the digestibility coefficient in four brazilian terrier dogs, two of each gender. Each digestibility assay had a five day adaptation period and five days to collect the material. The animals were weighted before and after the experimental period, and the food was served once a day. During the experiments, the food was weighted before and after being offered. Each animal ate approximately 50g food/Kg body weight. The feces were collected daily, and freezed at - 40C. After the feces collection fase all the freezed material was defrosted, homogenized and pre-dryed in a ventilated stove at 600C, so the bromatological analyses of food and feces were done. In the first experiment the feet had the highest values for CP and MC, and the back, the highest values for DM, OM and fat. Among the tested ingredients in the second experiment, the liver had the highest values for OM, CP, and gross energy (GE), and the MSM had the highest values for MM and DM. The head had the highest values for fat content. Cooking had no significant effect on the ingredients tested, but, the general observation was that the cooked ingredients had lower values for CP and higher values for fat content. Considering the digestibility coefficient the OM and CP of neck had a significant increase when it was used in the cooked form, but, the ME and the digestible energy (DE) values decreased considerably. Considering the back, the heat treatment resulted in a significant reduction of ME and DE and in the feet, the digestibility coefficients of DM, OM, CP, ME and DE were higher using the same treatment. Considering the head, only the CP digestibility coefficient had a significant improvement relative to the raw component. The digestibility coefficients of DM, OM, CP, DE,and ME had a significant increase when the MSM was cooked. Yet, when the liver was cooked, the CP, DE and ME digestility coefficients had a significant reduction. In relation to the ME ingestion on the second experiment, the groups of animals that ingested raw and cooked head had a significant higher values when compared to the dogs fed with liver and MSM in the raw and cooked form. It was concluded that it is possible to use all the ingredients tested in dog foods formulas, but it must be considered their real nutritional values. The inclusion of MSM deserves special attention, since it presented the lowest values for GE and ME as well as the lowest digestibility coefficients for DM and CP specially when raw. The heat treatment influenced positively the digestibility of neck, feet, head and MSM, while cooking the liver had a negative effect on the digestibility of protein and DE and ME. .