Evaluation of chemical composition of 6 available by-products in the North of Morocco

English. peer reviewed

English. In the northern region of Morocco, goat breeding is the dominant activity of farmers. This livestock plays a major economic role in the contribution of more than 70% of household income. His diet is based essentially on forest rangelands characterized by a variable feed offer. Therefore, it is necessary to diversify and improve its feed calendar to reduce overgrazing and increase livestock productivity. This work aims to characterize the chemical composition of agricultural by-products to be introduced in the diet of goat herd. The studied by-products was residues of watermelon, melon, zucchini, tomato, sunflower and peanut. These samples were collected in the different places in the region of the north of Morocco. In the laboratory, they were dried in oven at 60°C and subsequently ground and sieved to 1 mm diameter. The studied composition parameters were dry matter, ash, total nitrogen and fat. The chemical composition of these samples was determined by the methods of AOAC (1997). The means and the standard error of means were calculated using SAS software. From results, dry matter of by-products varies from 16.4% in watermelon residues and 96.7% in sunflower residues. The sunflower residues has a low mineral content of 3% while the melon residue contains 26.5% of mineral matter. The nitrogenous matter ranges from 2.6% in sunflower residue to 19.5% in watermelon residues. The highest fat content was recorded in melon residues (5.1%). Sunflower residue is lower in fat (1.4%). In conclusion, sunflower and peanut residues drier than the other by-products and contain less mineral matter, fat and nitrogenous matter. These by-products represent a free feed that can take their place in feed calendar in the northern region of Morocco for the goat population. However, to introduce them in the diet, it is necessary to evaluate their nutritional values.