New York Science Journal 2010;3(5) EFFECT OF STRAIN ON GROWTH, CARCASS CHARACTERISTICS AND MEAT QUALITY OF BROILERS REARED FOR 12 WEEKS. Chukwuka Okwunna Kosarachukwu*, Oscar Okechukwu Micheal Iheshiulor, Apeh Omede, Prince Ifeanyi Ogbuewu. Department of Animal Science and Technology, Federal University of Technology, P.M.B 1526, Imo State, Nigeria. okwy2k5@yahoo.com ABSTRACT: A study was conducted to evaluate the sensory properties of meat obtained from different broilers strains reared for 12 weeks. One hundred and sixty-two day-old birds as hatched from three commercial broiler strains (Ross, Abor Acres and Anak) were raised to 12 weeks of age. Each strain consisted of 54 birds and each group sub-divided into 3 replicates of 18 birds each. The birds were fed broiler starter diet for 4 weeks and finisher diet for 8 weeks. There were significant (P< 0.05) strain differences on body weight gain, dressing percentage abdominal fat and GIT. Differences in the daily feed intake also were significant (P< 0.05). Ross and Anak strains were statistically similar (P > 0.05) in final body weight and dressing percentage. The result showed no significant differences (P>0.05) in tenderness, flavour, hedonic score and cooking loss among the strains. [New York Science Journal 2010;3(5):112-116]. (ISSN 1554 – 0200). Key words: Broiler strain, carcass characteristic, meat quality. INTRODUCTION The poultry industry is going through a gradual but definite change in product differentiation in response to consumer and industry demands. To implement these changes, genetic improvements have focused primarily on selection for growth rate, feed conversion efficiency and degree of muscling resulting in gross changes in commercial poultry. During the last 50 years, the amount of time required to reach market weight and the quantity of feed needed to produce a kg of meat have been reduced by 50% (Anthony, 1998). While concomitant significant improvements have been accomplished in husbandry practices, disease prevention and nutrition, it has been estimated that 90% of the phenotypic changes in poultry have come from genetic progress (Havenstein et al, 1994 a, b). However, coincident with genetic improvement, other characteristics in live animal performance and meat quality have also changed. Siegel and Dunnington (1987) reported that there has been an increase in physiological breakdowns in meat- type chickens as a result of genetic progress for rapid growth. Sante et al (1995) reported that high performance turkey breeds have a higher rate of meat postmortem pH decline compared to slow-growing breeds. The marketing of poultry has been greatly diversified with a significant increase in cut-up (parts) and processed products (Le Bihan-Duval et al, 2001). Demand for high-quality parts and further-processed convenience foods have driven the poultry industry to change its marketing practices (Roenigk and Pedersen, 1987; Watts and Kennett, 1995). Although increasing the market weight of birds generally increases cost of production, the fixed costs of processing are reduced. In addition, only a finite number of birds may be processed in a plant within a given period. Therefore, increasing the market weight of birds allows for increased plant meat yield without increasing the bird capacity of a processing plant (Saleh et al, 2004). There is limited published research dealing with birds grown to the weights now demanded for further processing. The objective of this study was to determine the effect of strain on growth rate, carcass characteristics and meat quality of broilers reared for 12 weeks in the tropics. Materials and Method Site of Study: The experiment was conducted at the Teaching and Research Farm of the Federal University of Technology, Owerri, Imo State, Nigeria. Owerri is located in the south eastern part of Nigeria within the tropical rain-forest belt. It is at the altitude of 90m and the mean annual rainfall, temperature and humidity are 2500mm, 26.5-27.5 0 C and 70-80% respectively. Federal University of Technology, Owerri, is located at latitude 5 ο 27N and longitude 7 ο 02 E (FDALR, 1985). http://www.sciencepub.net/newyork newyorksci@gmail.com 112