عنوان مقاله [English]
Background and objectives: As respects Food processing may increase livestock performance. Today some methods of grain processing have been considered. On the other hand, lack of animal feed, especially with the development of industrial methods of animal husbandry waste in many parts of the world, has led farmers and researchers to think about identifying and using agricultural and livestock waste and new food sources for animal nutrition, including poultry manure. And urea is mentioned in the diet of ruminants. Due to the fact that no research has been done on the effect of barley grain processing methods and non-protein nitrogen sources in the diet on growth performance, nutrient digestibility and carcass characteristics in of Afshari breeding fattening lambs, the present study was conducted.
Materials and methods: This experiment was conducted in a completely randomized design with seven treatments including a control treatment containing whole barley grain (without milling) and without urea and chicken manure, treatments 2, 3 and 4 respectively containing processing method of milling, filling and pelleting with a certain level of urea. (1%) And treatments 5, 6 and 7 containing processing methods of milling, filling and pelleting with a certain level of poultry manure (12%) were performed on Afshari breeding fattening lambs. Each treatment consisted of 5 fattening lambs at the age of 3 months 24±1 which were kept individually in separate cages for 14 days of acclimatization period and 84 days of fattening period. Dry matter, ash, crude fiber, crude fat and crude protein were determined using the method (AOAC, 2000), Neutral detergent fiber and Acid detergent fiber based on the method of Van Soest et al (1991). At the end of the rearing period, three heads from each treatment were randomly sacrificed and hot carcass weight and cold carcass weight and its components were measured.
Results: The number of daily feed intakes, daily weight gain and feed conversion ratio were significantly different between experimental treatments. The apparent digestibility of dry matter and organic matter were significantly different, and the control treatment (whole barley grain without urea and poultry manure) had the highest apparent digestibility. Digestibility in non-fibrous carbohydrates was significantly different, so that treatment 5 (processing method of milling with poultry manure) had the highest apparent digestibility. Experimental treatments were significant on thigh weight, neck weight, tail weight, ventricular fat weight, carcass length and half-carcass length.
Conclusion: The results showed that barley grain processing methods with non-protein nitrogen sources had a significant effect on daily weight gain, dry matter consumption, feed conversion ratio, some organs of fattening lambs, digestibility of dry matter, and organic matter compared to the control group. In general, it is possible to use barley grain processing with urea (1%) and poultry manure (12%) in the diet of fattening lambs without harmful effects on production parameters and fattening performance.