ISSN 1392-2130. VETERINARIJA IR ZOOTECHNIKA (Vet Med Zoot). T. 76 (98) Supplement. 2018 79 CARCASS CHARACTERISTICS AND QUALITATIVE MEAT TRAITS OF BROILER CHICKENS FED SUPER PRE-STARTER DIET Vilma Sasyte, Jolita Klementaviciute, Asta Raceviciute-Stupeliene, Agila Dauksiene, Vilma Viliene, Vilija Buckiuniene, Saulius Alijosius, Romas Gruzauskas, Ernesta Tolpeznikaitė Institute of Animal Rearing Technologies, Faculty of Animal Husbandry Technologies, Veterinary Academy, Lithuanian University of Health Sciences Tilzes str. 18, LT-47181, Kaunas, Lithuania *Corresponding author: Agila Dauksiene Lithuanian University of Health Sciences, Tilzes str. 18, 47181, Kaunas, Lithuania Phone: +370 37 36 35 05; e-mail: agila.dauksiene@lsmuni.lt Abstract. The aim of present study was to assess the effects of animal blood plasma with soy protein concentrate and tryptophane in the super pre-starter diet of broiler chickens. The study was carried out with a 1000 ROSS 308 cross broiler chickens of 1-42 day old. Broilers were divided into 2 groups of 500 chickens. The birds received the experimental diets from 1 to 8 d of age. The chickens were fed a standard pre-starter diet (Control) and super pre-starter diet (Treatment). In diet of treatment group, the wheat, soy-bean meal and corn were replaced with blood plasma meal (5%), soy-bean concentrate (5%) and tryptophan (0.046%). The birds of control and treatment groups received the same standard diets from 9 to 42 d of age. The parameters of productivity, such as body weight (BW), feed conversion ratio (FCR) and mortality during the experiment were estimated. At the end of the trial the chicks were killed and after laparotomy internal organs and digestive tract were removed and weighed. The length of intestinal tract was measured. Carcass meat characteristics were evaluated. The physical and chemical indices of the meat, such as drop losses, water holding capacity, meat cooking losses, meat tenderness, amount of intramuscular ash, fat, total protein and dry matter (DM) was determined. The results of the study showed, that the final BW by 3% were increased in treatment group (P<0.05). The FCR was decreased by 3% during all experimental period, compared with control (P>0.05). The intestinal weight with chymus, weight of heart, liver, gizzard and proventriculus were higher for broiler chickens which received a super pre-starter compound feed. Application of super pre-starter diet had a positive effect on carcass characteristics of broiler chickens. The carcass yield was improved by 2%, breast and leg muscle yield by 1%, compared with the control group (P>0.05). The drip-loss, water holding capacity, DM, intramuscular fats and ash of breast as well as the leg meat were increased, compared with control group (P>0.05). In summary the application of super pre-starter diet for broiler chickens at the age of 1-8 days could improve the BW and decrease the FRC with better carcass characteristics of broiler’s meat. Keywords: super pre-starter feed, carcass characteristics, meat quality, broiler chickens. Introduction. Progress in genetics and management has allowed the poultry industry to produce heavier chickens in a more efficient manner. Consequently, the age to market in broiler chickens has been gradually reduced. On the other hand, research work conducted during the past decade in the area of the chick’s early development has shown that during the first week post- hatch, the digestive system is not fully developed. Because the first week post-hatch currently represents a more critical part of the broiler’s productive life, and the chick’s digestive capabilities are limited at this age, special attention is being given to the nutritional needs of the chicken during this period in order to maximize performance. One strategy to address this is the use of super pre-starter diets, with the goal of providing highly digestible ingredients that the young chick will be able to utilize more efficiently (Garcia, 2006). The design of such feed will be different when it is to be part of a drug-free nutrition program. In such cases, not only alternative anti- pathogen agents are required, but proteins of high digestibility are also a must. Among them, animal plasma can provide a double function as a gut health agent, it have good balance of amino acids, especially lysine, in addition to being highly digestible (Mavromichalis, 2016). Longer intestinal villi have been observed after inclusion of porcine plasma in broiler diets (Jamroz et al., 2011, 2012). The activity of blood by-products has been associated with specific immunoreactive globulins and nucleotides that exist in the composition of blood products (Moretó and Pérez-Bosque, 2009). Various processed soybean products have been used in animal and poultry feeding. These include soybean protein concentrates (SPC), soybean protein isolates (SPI), and products in which the soybean was pretreated with enzymes and/or microorganisms. Processed soy products are distinctly different to soybean meal (SBM) thus they have much lower ANFs activities, and contain a significantly lower amount of oligosaccharides and antigenic substances. Therefore, their nutritive value is much better than that of SBM and can be incorporated at high levels in animal diets (Peisker, 2001). Replacement of SBM with these processed products in animal diets is believed to result in a better growth performance because SBM may contain enough ANFs to exert their antinutritional effects (Saki et al., 2012). It has been concluded by van der Eijk (2015) that partial or complete