Animal husbandry presents the most intensive branch of agriculture and has multiple significances, for both producers and consumers. The increase in the production of the meat, milk, eggs, among others is the foundation for the improvement of the nutrition structure of the population with highly valuable animal proteins.

Production of the fatty poultry presents a form of agricultural production, which is, by its nature, closest to the industrial production. Accordingly, great work productivity and control of production processes is achieved (Filipović et al., 2009).

The solution of increased food production for people and animals is appliance and usage of new technologies in biotechnology, e.g. bio industry (Lazarević i sar., 2005). The main orienttation is presented by new technological processes which aim at the increase of nutritive value of the food for people and animals. Nowadays, many ways of thermal processing of oilseeds and cereals are used in the world: toasting, hydrothermal refinement, micronisation, microwave treatment, bielectrical heat treating (Marsman et al., 1998), but in Serbia the most often used are the process of extrusion and hydrothermal process (Sakač et al., 2001; Filipović et al., 2007; Kormanjoš at al. 2007).

In the domestic production of forage mixtures, the corn has the leading position compared to other cereals, because of high energy content (16.2 MJ/kg), starch, comparably big content of oil and low level of cellulose. Corn, apart from the best digestibility, also has the best taste compared to other grains (Bekrić, 1999).

Proper conduction of the thermal process provides the reduction of thermo labile antinutritients to an acceptable level, increase of digestibility of some nutritients (proteins, oil, carbohydrates), as well as the improvement of sensory features and the microbiological picture of the final product (Filipović et al., 2003; Kormanjoš et al., 2007a). Parallel with the reduction of the content of the antinutritients it is necessary to preserve nutritionally valuable thermo labile components, so the process requires finding a compromise between the two efforts.

Estimation of production expenses of fattening poultry in case of extruded and non extruded corn in forage mixtures is based on natural indicators determined based on the research conducted at the examined farm. It is an individual household which has its own food production for animals, with a farm capacity 3000 fattening chicken in turnus. During the fattening, feeding of one half of chicken was practiced with the food that contained extruded corn (experiment E), while the other half was fed with a mixture in which the corn has not been treated (control C). Calculation of the expense for food has been derived according to the standard of expenses for the preparation of animal food, based on market prices of certain kinds of food and experience normative. The expense for other material has been calculated according to the expenditure made on the observed farm and market prices. Investments into buildings and the equipment have been calculated based on standard investments in objects and equipment. Expenses of the buildings and equipment amortisation have been derived based on the assumed lifetime of the utilised means (Marko et al., 1998). Expenses for salaries have been calculated in accordance with realised expenses. Expenses for the energy consumption have been calculated on the basis of realised expenditure of the electrical power and fuel. Apart from that, the calculation includes expenses of veterinary and selection services. Calculation of the income is based on clarification of total income from the above mentioned production, whereby the financial result presents the income from the overall production (Andrić, 1998).

During the analysis of the observed production, production results for both groups have been followed closely. The follow up was conducted on a weekly level. It is extended fattening in duration of seven weeks. Since the feeding regime has different effects depending on the age of the poultry, better insight into the overall effects of the food with extruded corn was enabled. The main production indicators are given in the Table 1. Lower mortality rate could be pointed as the most obvious result of the usage of extruded corn in feeding. In case of feeding with forage mixture with addition of non extruded corn, 96 chickens have died in total. If this is compared to the mortality in case of feeding with the mixture with extruded corn (20 chickens), it is possible to draw a conclusion about the great advantages to the usage of extruded corn in food for maintaining health condition of the poultry. Besides, provided results are specially expressed in the first four weeks of the fattening (Graph 1).

The second factor of significance for the overall production and the achieved economic result is the conversion of food. The calculation of the achieved conversion shows that the group fed with the extruded corn achieves better conversion whereby, on the level of the overall fattening makes 2.04 gr of forage mixture per kilogram of weight gain. Feeding with the forage mixture, the achieved conversion of the food is 2.13 kg per kilogram of the weight gain. The overview of the conversion change during the fattening gives a better insight into the food conversion. The overview has been made according to the available data and is given on the Graph 2.

Description	Unit	Quantity	Price	Total
Bedding	bale	120.00	1,05	126,00
Vaccine	pcs.	3,000.00	0,0068	20,40
Vaccine	pcs.	3,000.00	0,0142	42,60
Vitamins	pcs.	1.50	23,16	34,74
Revaccination	pcs.	3,000.00	0,01	30,00
Revaccination	pcs.	3,000.00	0,01	30,00
Electric power	-	-	194,70	194,70
Gas	-	-	315,80	315,80
Salaries	-	-	336,80	673,60
Total				1.467,84

Expense category	E			C
	Total expenses	Price, €	%	Total expenses	Price, €	%
Amortisation	705,00	0,48	15,83	705,00	0,50	15,84
Food expenses	3.014,05	2,04	67,66	3.008,85	2,14	67,62
Salaries	336,84	0,23	7,56	336,84	0,24	7,57
Expenses for the energy	255,26	0,17	5,73	255,26	0,18	5,74
Expenses of other and additional materials	143,68	0,10	3,23	143,68	0,10	3,23
Total	4.454,84	3,01	100,00	4.449,64	3,17	100,00

Description	E	C
Total income	5.159,75	4.930,26
Total expense	4.454,84	4.449,64
Benefit	704,91	480,62

CONCLUSION

• The profit achieved per one turnus amounts to 704,91 € for the group fed with the mixture with addition of extruded corn and 480,62 for the group breed by standard forage mixtures, e.g. 0,18 €/kg and 0,12 €/kg per kilogram of produced chicken.
• Economy calculated from the ratio of total income and total expense makes 1.16 for the group fed with the mixture with addition of extruded corn and 1.11 for the group breed by standard feeding system.
• Detailed analysis of economic indicators shows very low profitability of the production. The realised profitability of the production makes only 10,7% for the group fed with the mixture with addition of extruded corn and 7,3% for the group breed by standard forage mixtures. The obtained values in both cases very low and indirectly points to the need for the state subventions of investments in this sphere.
• Regardless of that, all presented indicators point out the justifiability of the usage of extruded corn in the preparation of food for animals.

ACKNOWLEDGEMENTS