ABSTRACT In this study, the influence of carcass parts weights (thigh, breast, wing, back weight, gizzard, heart, and feet) on whole carcass weight of white turkeys (Big-6) was analyzed by regression analysis based on ridge regression and factor analysis scores. For this purpose, a total of 30 turkey carcasses of 15 males and 15 females with 17 weeks of age, were used. To determine the carcass weight (CW), thigh weight (TW), breast weight (BRW), wing weight (WW), back weight (BW), gizzard weight (GW), heart weight (HW), and feet weight (FW) were used. In the ridge regression model, since the Variance Inflation Factor (VIF) values of the variables were less than 10, the multicollinearity problem was eliminated. Furthermore, R2=0.988 was obtained in the ridge regression model. Since the eigenvalues of the two variables predicted by factor analysis scores were greater than 1, the model can be explained by two factors. The variance explained by two factors constitutes 88.80% of the total variance. The regression equation was statistically significant (p<0.01). In the regression equation, two factors obtained by using factor analysis scores were independent variables and standardized carcass weight was considered as dependent variable. In the regression model created by factor analysis scores, the Variance Inflation Factor values were 1 and R2=0.966. Both regression models were found to be suitable for predicting carcass weight of turkeys. However, the ridge regression method, which presented higher R2 value, has been shown to better explain the carcass weight.

ABSTRACT The subject of this study was to figure out the effects of lentil by product (LP) on growth performance and carcass traits of the white heavy turkeys. To accomplish this goal, a total of 210 day old big-6 turkey chicks were used. The birds were divided into 7 seven groups with 3 replicates. The 1st, 2nd, 3rd, 4th, 5th, 6th and 7th groups received 0, 5, 10, 15, 20, 25 and 30 % lentil by product, respectively. All the diets were made as izonitrojenic and izocaloric. The highest live body weights of males and females were observed in the control group at the end of the 15th week, which was the time of slaughtering of females, however the differences between the control and the 2nd, 3rd and 4th groups were not significant (p>0.05). The same differences continued for males at the end of the 17th wk of age, which was the time of slaughtering of males. Similar results were observed in carcass traits, as well. The best FCR was noted in the control group and it was significantly (p<0.05) different than in the treatment groups. The lowest and highest feed intake was observed in the 7th and 3rd groups. No significant differences were observed between control and all treatment groups. As a result, it could be said that lentil by product could be added into turkey diets up to 15% with no negative effect on live body weight and carcass traits because there was no significant differences between control and treatment groups (5, 10,15 % LP).