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  • Connection of crude protein content and amino acid content of forage and medium quality winter wheat varieties in the relation of quantity and quality
    73-79
    Views:
    140

    We analysed the crude protein content, amino acid content, amino acid composition of four forage and milling III. quality winter wheat varieties (Magor, Hunor, Róna and Kondor) from their samples from five following years (2003, 2004, 2005, 2006, 2007). We found that quantity of essential and non-essential amino acids rose with increase in crude protein content. On examination of protein amino acid composition in relation to crude protein content we found that the crude protein content increased the quantities of the non-essential amino acids also rose, while those of the essential amino acids decreased as the lysine, the limiting amino acid of wheat. We also established that, as crude protein content increased, the biological value of the protein decreased.

  • Connection of protein and amino acid content of forage and medium quality winter wheat varieties
    101-107
    Views:
    101

    We analysed the crude protein content, amino acid content, amino acid composition of four forage and milling III. quality winter wheat varieties (Magor, Hunor, Róna and Kondor) from their samples from five following years (2003, 2004, 2005, 2006, 2007). We found that quantity of essential and non-essential amino acids rose with increase in crude protein content. On examination of protein amino acid composition in relation to crude protein content we found that the crude protein content increased the quantities of the non-essential amino acids also rose, while those of the essential amino acids decreased as the lysine, the limiting amino acid of wheat. We also established that, as crude protein content increased, the biological value of the protein decreased.

  • A growth model to predict body weight and body composition of broilers
    17-24
    Views:
    329

    Models predicting the nutrient partitioning and animal performance have been developed for decades. Nowadays, growth models are used in practical animal nutrition, and they have particular importance in precision livestock farming. The aim of the present study was to introduce a broiler model and to provide examples on model application. The model predicts protein and fat deposition as well as the body weight of an individual broiler chicken from digestible nutrient intake over time. Feed intake (FI) and the digestible nutrient content of the feed are inputs as well as some animal factors like: initial BW, feed intake at 1 and 2 kg of BW, precocity and mean protein deposition. The protein and energy metabolism is represented as in the classical nutrient partitioning models. The protein deposition (PD) is driven by digestible amino acid supply and is under “genetic control”, the so-called potential PD limits the actual PD if protein is oversupplied.

    The authors discuss how the model can be used to simulate the animal response upon different scenarios. Examples are given to show that the diet might be limiting if some animal trait is changed. Applicability of the model has shown through running the model by using different feed strategies (three- vs five-phase-feeding) and variations with animal factors. In conclusion, growth models are useful tools to support decision making for defining the most suitable feeds used in a broiler farm. The model presented in this paper shows a high sensibility and flexibility to test different scenarios. By challenging the model with different inputs, the animal response in terms of changes in body weight and feed conversion can be understood more by studying the shift in deposition of chemical constituents. The examples provided in the present paper shows the benefit of using mathematical models and their applicability in precision nutrition. It can be concluded that the growth model helps to apply “from desired feed to desired food” concept.

  • Alternative protein sources in the nutrition of farm animals
    21-31
    Views:
    363

    Protein requirement and its demand of farm animals became one of the critical problems in nutrition on a global scale. Protein requirement has been an explicit demand for a long period with soybean meal and animal protein, but recently there are some limitations in relation to their use and the availability of the high quality fishmeal decreases constantly. For this reason there is increased demand for finding new protein sources which could be the alternatives of soybean meal and fishmeal. Alternative protein sources can be divided into seven categories, according to their origin. In different countries, their use depends on the availability in large quantity and at reasonable price.

    There is a long tradition of using legume seeds, as alternatives of soybean. Most of them contain some anti-nutritive compounds, but it can be reduced with systematic selection. Oilseed meals are also generally use in poultry and pig nutrition, but those crude protein content varied, depending on the oil extraction technology. Green fodder and leaf protein was also proposed as alternative protein sources, but their use is limited, in particular because of the market price. The amount of bioethanol and starch industry by-products increases gradually in recent years, therefore those became alternatives of soybean meal, or in much less extend, fishmeal. However, amino acid composition of such by-products are far from optimal for poultry and pig; therefore, in the case of their use amino acid supplementation is necessary. Several novel protein sources are proposed in the last decade, such as algae or insect proteins. Recently, their availability and use is limited, but in the near future those would be alternative protein sources in monogastric animal nutrition.