Effect of using rice bran enriched with fish waste on microbial population and immune system in broiler chickens.

Dissertation for obtaining a master's degree (M.Sc) in the field of animal science

Animal nutrition trend

Abstract

This study is to compare the effect of rice bran enriched with fish waste on the microbial population of the digestive tract and the humoral immune response of 200 broiler chickens. One-day breeding of Ras 308 strain was done in the form of a completely randomized design with 5 treatments and 4 replications and 10 birds per replication. The experimental treatments included the first, second, third, and fourth treatments with fish waste amounts of 2.5, 5, 7.5, and 10% of fish waste, respectively, and the fifth treatment (control) without fish waste and all five treatments contained 10% of rice bran. Data analysis was done using SAS software and comparison of averages was done with Duncan's method. According to the obtained results, it was found that the average number of lactobacillus and coliform in the contents of the cecum at 47 days old did not have a significant difference among the treatments (P<0.05). The results of the Salmonella search were negative in all treatments. Also, there was no significant difference between the two periods of anti-SRBC at 28 days old (P<0.05). However, there was a significant difference in the anti-SRBC titer at 42 days (P<0.05). The mean titer of antibody against Newcastle virus was not significantly different at 35 days (P<0.05), but a significant difference was observed at 42 days (P<0.05). There was a significant difference in the average titer of antibody against Gamboro vaccine virus in two periods of 21 and 42 days (P<0.01). The results showed that the use of 10% of rice bran enriched with 10% of fish waste increased the number of intestinal lactobacilli and subsequently increased the level of poultry immunity.

Key words: immune system, rice bran, microbial population, broilers, fish waste.

1- Introduction

In today's world, due to the increase in population and decrease in human resources, food supply is one of the reasons for the superiority of successful systems over other systems. In the current situation, the necessity of finding a solution for increasing food production becomes more apparent. One of the essential needs of human nutrition is the supply of animal protein, which poultry meat has been considered as a valuable source of protein. Among the things that are of interest to experts in nutrition and poultry breeding is the protein required in poultry diet and, of course, essential amino acids (Shahir et al., 2013). Supplying food ingredients or in other words preparing rations in poultry houses accounts for about 55-60% of current production costs (Rahimi, 2018). The per capita consumption of chicken meat was 18 kg in 1384 and reached 22 kg in 1388 (Agricultural Statistics, 1388).

       Animal protein plays an important role in providing human food needs, and currently, there is a shortage and poverty of animal protein in our country. In Iran, red meat, milk, white meat and eggs are used to provide animal protein in human nutrition. Increasing the amount of red meat and milk production in the short term is not easily possible due to the long production process and the limitation of pastures in the country. In addition, increasing the consumption of vegetable proteins by people today has failed. The reason for this is more energy consumption during their processing, which was initially considered for livestock products. The production of synthetic compounds similar to meat is also associated with high energy consumption, and their limited production has been associated with problems from the economic aspect as well as from the point of view of their acceptance by consumers. Chicken meat is the cheapest type of meat in most countries, which is undoubtedly the most important reason for the success of this industry worldwide. This superiority in the competition is basically due to continuous improvement of production efficiency and acceptance of new ideas and creativity by producers and agricultural organizations (Golian and Salar Moini, 1383).

One of the strategies for success in the poultry farming industry is proper nutrition, and proper nutrition has been considered in various ways, including the relationship between nutrition and growth speed and the improvement of the immune system. In this regard, nutritional conditions affect immunology and response to infectious agents in the host, and on the contrary, acute or chronic infectious diseases will also have a detrimental effect on nutritional conditions.In the case of control, prevention is more important than treatment because, firstly, treatment is difficult in large areas and secondly, its costs are high. While disease prevention is easier and less expensive. Therefore, it is necessary to adopt measures that consider the prevention of diseases instead of treatment. In order to prevent the occurrence of diseases and increase resistance, there are several methods, including vaccination, the use of antibiotics, etc., despite the improvement of the immune system, each of these methods has disadvantages, such as the development of resistance of microorganisms to antibiotics, and the duration of the use of antibiotics and the distance between the last stage of their use and the time when the broilers are transported to the slaughterhouse should be investigated, and even if all conditions are followed, the possibility of side effects due to the remaining of these substances in the There are carcasses and in the body of people who use these products especially in large quantities in their diet. As a result, the concerns caused by the adverse effects of the high consumption of antibiotics in the feeding of broiler poultry are expanding day by day (Jill et al., 1997).

In recent decades, in order to increase the production efficiency of livestock and poultry, compounds have been used as food additives and growth stimulants to improve the use of nutrients in the diet and improve growth. They are widely used, but considering the harmful effects of antibiotic use and restricting their use, animal and poultry nutritionists are looking for alternatives to these compounds (Elaine Dale [1], 2001). In Iran, before 1333 Shamsei, chicken breeding was done only in a traditional and domestic way, and the consumption of chicken in today's form was not common among the general public, and it was mostly used for entertaining guests or treating patients. In this year, by importing a number of modified breed chickens and hatching eggs from abroad, the foundation of poultry farming was laid in a new way and gradually developed. The poultry breeding industry in our country, Iran, consists of six main activities: line chicken breeding, ancestor chicken breeding, mother hen breeding, day-old chick production, egg-laying chicken breeding, meat chicken breeding and a half-breeding breed (Iran Statistics Center, 2018). Among the mentioned activities, it is very important to know how broiler farms work, because the final product of this category of poultry farms is chicken meat, which as an important protein and brain substance has a significant contribution in providing part of the animal protein needed by the society (Iran Statistics Center 2018). As it was said, the production of chicken meat in Iran became common in the middle of the 1340s.  According to the statistics of the Ministry of Jihad and Agriculture, the production of chicken meat in Iran has increased from 420 tons in 1370 to 1360 thousand tons in 1385. Iran's share of world meat production in 2007 is 70.1%. Per capita consumption of chicken meat in urban areas increased from 11.9 kg in 1380 to 17.41 kg in 1385. According to the statistics provided by Jihad Keshavarzi Organization, the per capita consumption of chicken in Iran was 19.30 kilograms in 2006, and the per capita consumption of chicken meat in the world was announced at 12.9 kilograms in 2006, so the per capita consumption of chicken meat in Iran is higher than the world average (Iran Statistics Center, 2008). The cost of chicken meat in different countries is different according to the production technology, climatic conditions, cost and production management. Among the major producing countries, Brazil, China, and the United States have lower production costs and, consequently, lower prices due to cheap access to chicken meat and high technology. The examination of chicken meat production cost items in Iran shows that the cost of feed accounts for the largest amount of production costs (seventy percent), followed by the cost of buying day-old chickens (sixteen percent) (Statistical Center of Iran 2018). Therefore, by making changes in the composition of consumed rations, in addition to reducing costs, we can also think about increasing the production balance. In addition, the amount of chicken meat production in Gilan province in 2009 was announced as 23.25 thousand tons (Jihad Keshavarzi organization of Gilan province, 2009).