The effect of rosemary powder and vitamin E on performance, blood parameters, immune system, and the quantity and quality of broiler chicken carcasses.

Dissertation for receiving a master's degree (MSc) in the field of animal science - animal nutrition. An experiment was conducted in the form of a factorial design. For this purpose, 270 one-day-old male chicks, Ras 308 strain, were subjected to nine treatments: first treatment: without rosemary powder and vitamin E, second treatment: without rosemary powder plus one hundred mg/kg of vitamin E, third treatment: without rosemary powder plus two hundred mg/kg of vitamin E, fourth treatment: half percent of rosemary powder and without vitamin E, fifth treatment: half percent of rosemary powder plus one hundred mg/kg of vitamin E, treatment Sixth: half percent rosemary powder with two hundred mg/kg of vitamin E, seventh treatment: one percent rosemary powder without vitamin E, eighth treatment: one percent rosemary powder with one hundred mg/kg vitamin E, ninth treatment: one percent rosemary powder with two hundred mg/kg vitamin E. The results showed that rosemary powder and vitamin E had no effect on the performance of broiler chickens in the initial period (P<0.05); However, the level of half percent of rosemary powder and the level of 200 mg/kg of vitamin E were effective on the performance of broiler chickens at the end of the period and at the end of the period (P<0.05). Rosemary powder had a significant effect on duodenal width, weight, relative weight and length of jejunum, length and width of colon, weight and relative weight of right rectum (P?0.05).  Vitamin E had a significant effect on the width of the duodenum and the length of the right rectum (P?0.05). Rosemary powder did not affect the weight of a chicken compared to the control (P<0.05), but the level of half a percentage of rosemary powder increased the weight of a chicken significantly compared to the level of one percent of rosemary powder (P?0.05). Two hundred mg/kg of vitamin E significantly increased the weight of one chicken compared to the control (P?0.05). Rosemary did not affect the immune response of broiler chickens (P<0.05); But vitamin E was effective on the immune response of broilers to SRBC (P?0.05). The results showed that rosemary powder and vitamin E had an effect on the level of uric acid, albumin and globulin in the blood serum of broiler chickens (P?0.05); However, they did not affect the level of cholesterol, triglyceride, VLDL, HDL, LDL, LDL/HDL, SGOT, SGPT, uric acid, total protein, albumin and globulin (P<0.05). Although vitamin E and rosemary powder did not affect the amount of thiobarbituric acid production in the first week (P<0.05); But the levels of half percent of rosemary powder and two hundred mg/kg of vitamin E could significantly reduce the amount of meat oxidation and TBA production on the zero, fourth and fourteenth days (P?0.05).

Key words: broilers, rosemary powder, vitamin E, performance, blood parameters, immune system, quantity, quality

1 The importance of animal husbandry in Iran and the world

Agriculture provides the main source of livelihood for people compared to other industries. Livestock constitutes more than half of the total output of the agricultural sector (Kamalzadeh[1] et al., 2008) and is important in many developed countries. Domestic animals and their products have expanded and grown rapidly in developed countries (Apon [2], 2004). In Iran, domestic animals are an important national resource and more than half of the rural population depends on domestic animals for their lives. And livestock play an important role in providing the livelihood of poor villagers and creating employment (Kamalzadeh et al., 2008).

1-2 Importance of poultry in human life

Poultry or domestic birds are important for their meat and eggs and are an important source of animal protein. Poultry meat is rich in protein and is a good source of phosphorus and other minerals, B vitamins. Poultry meat has less fat (5-3.5%) than beef and chicken liver is rich in vitamin A. The proportion of unsaturated fatty acids is higher than saturated fatty acids, and this amount of fatty acids indicates that poultry meat is healthier than red meat. As a result, these factors have led to the development of poultry production.  Along with the economic growth, the demand for protein has increased in developed countries, especially food of poultry origin.The demand for low-calorie food and the change in lifestyle make consumers spend less time preparing food. Poultry meets consumers' requests for easy cooking. The five factors that have increased the popularity of chicken meat are: 1- Its reasonable price compared to other foods; 2- proper nutritional content (low fat); 3- Easy to prepare; 4- versatility; 5- Being comfortable and easy to serve for feeding purposes (FAO [3], 2010; Slawmayer [4] et al., 2008; Spernakova [5] et al., 2007).

1-3 Importance, status and statistics of the poultry industry in Iran and the world

Poultry breeding in Iran has a long history and Its time goes back to ancient Iran and when the chicken was brought to Iran by Aryan men from the Indian subcontinent (about 2500-2000 years BC). In the last four decades, a lot of investment has been made in this sector (Esfahani[6] et al., 2012). According to published statistics, the share of meat, milk and eggs in the total food supply of the Iranian people in 2009 was 5 and 4.6 percent, and the world's annual meat production was 281,482 thousand tons. among which Iran's share was 2541 thousand tons. Also, the production of poultry meat in 2009 in the world was 92325 thousand tons; Iran's share was 1622 thousand tons. The per capita consumption of poultry meat and eggs in Iran is 22.2 and 7.7 kilograms, and it is predicted that the per capita consumption of meat in the world in 2030 will be 45.3 kilograms per year, which is expected to increase by 11% compared to 1999 (FAO, 2009; World Health Organization[7]). Achieving such a vision is possible under the shadow of ensuring the proper performance of farm animals, effort and diligence to maintain the health of animals in order to produce livestock products with excellent quality.

1-4 The place of rosemary[8] and vitamin E in poultry nutrition

The use of antibiotics as a growth stimulant has played a fundamental role in the poultry industry. But its use has decreased the trust of the society due to drug residue and bacterial resistance and its use as a growth stimulant has been prohibited (Polat[9] et al., 2011). Banning the use of antibiotics led animal nutrition science experts to think of a solution to produce natural foods and animal products with high quality. Accordingly, many researchers focused on the use of food seasonings such as probiotics [10], prebiotics [11], organic acids, plant extracts and antioxidants (Spernakova et al., 2007; Frankic [12] et al., 2009). Natural food seasonings of plant origin are healthier and safer and have been used for medicinal purposes for centuries; And some of them played an important role in maintaining health and improving human life for a long time (Osman[13] et al., 2005; Ghazaleh[14] and Ali[15], 2008). Among the medicinal plants is rosemary, which is a good source of antimicrobial compounds, stimulators of the digestive system, and antioxidants. The beneficial effects of medicinal plants and their products, including extracts, oils, have been confirmed as herbal seasonings (Soltan[16] et al., 2008; Khaliq[17] et al., 2011). These compounds affect the production and health of poultry by stabilizing the microflora of the digestive system, preventing the colonization of pathogens (Takli [18] et al., 2006) and producing digestive enzymes (Lee [19] et al., 2004). It is well known that the phenolic compounds found in plants and their extracts have antioxidant activity in lipid systems (Frag[20] et al., 1989; Diqtun[21] et al., 1993). Supplementation of poultry diet with vegetable oils leads to weight gain, improvement of carcass quality and reduction of mortality (Mandel[22] et al., 2000; Hertremoff[23], 2001; Williams[24] and Loza[25], 2001). The presence of vitamin E in the organs of chickens and laying hens is important for maintaining health (Coetzee [26] and Hekaran, 2001; Bowe [27] et al., 2004). The presence of vitamin E in the blood is an indicator, especially important in preventive medicine [28], malabsorption syndrome [29], necrotic dermatitis [30]. In addition, vitamin E is an effective antioxidant that reduces the oxidation of the muscle cell membrane. Increasing the concentration of alpha-tocopherol increases food conversion rate, increases weight, reduces food consumption (Kandy [31] et al., 1992; Coetzee et al., 2001) and improves the function of the immune system.