The aim of this study was to compare some estimation methods (LS, M, S, LTS and MM) for estimating the parameters of simple linear regression model in the presence of outlier and different sample size (10, 20, 30, 50 and 100). To compare methods, the effect of chest girth on body weights of Karayaka lambs at weaning period was examined. Chest girth of lambs was used as independent variable and body weight at weaning period was used as dependent variable in the study. Also, it was taken consideration that there were 10-20% outliers of data set for different sample sizes. Mean square error (MSE) and coefficient of determination (R2) values were used as criteria to evaluate the estimator performance. Research findings showed that LTS estimator is the best models with minimum MSE and maximum R2 values for different size of sample in the presence of outliers. Thereby, LTS method can be proposed, to predict best-fitted model for relationship between chest girth and body weights of Karayaka lambs at weaning period, to the researches who are studying on small ruminants as an alternative way to estimate the regression parameters in the presence of outliers for different sample size.

This study aimed to investigate the body weight and some body measurements in Central Anatolian Merino sheep regarding ages and to carry out a comparative analysis between them. The study included a total of 60 animals aged 2, 3 and 4 years. The sheep were fed daily with hay, vetch, alfalfa and limited amount of concentrated feed (400 g head-1) until the pasture period, and pasture grass and mixed grass-clover hay during the pasture period. The live weights of the sheep of different ages in the farms were measured with a digital scale, and some body size were measured using a measuring tape and a measuring stick. When the live weight and chest circumference values of the 4-year-old sheep were compared with the data obtained in the other age groups (2 and 3 years old), and it was statistically significant, chest width and rump height values were found to be similar to those in the 3-age group. There were significant correlations between live weight and chest circumference, between withers height and rump height and significant correlations between live weight and chest width, body length with rump height, chest width with chest depth. In addition, significant correlations were found between live weight and chest depth, and between withers height, body length, and chest depth. Present findings revealed that the Central Anatolian Merino sheep can be beneficial in the development of meat-type sheep breeding.

In this study the heritability of body weights of Japanese quails (Coturnix coturnix Japanica) were estimated by using MINQUE (Minimum Quadratic Unbiased Estimation) methods. Firstly the variance components were estimated by using MINQUE method which were later estimated the heritability for weekly body weights. The estimation of heritability of body weights are following: for third week : 0.302±0.018; for fourth week: 0.70±0.15; for fifth week : 0.30±0.067

This study evaluated the correlation between scrotal circumference (SC), body weight (BW) and body condition score (BCS) in relation to breeding age in West African Dwarf (WAD) bucks. A total of 320 WAD bucks from birth to 15 months of age from various farms in Ibadan, Nigeria, were studied. They were grouped as A-birth to 3, B-4 to 7, C-8 to 11 and D-12 to 15 months old respectively, comprising of 80 bucks per group. Semen was collected from 10 randomly selected bucks in each group and analysed. Results showed positive correlation between SC and age; SC increased with age; and at about 8 months of age and over, a consistent SC of 17 cm–18 cm was observed. BW also increased with age; BW significantly affected SC. Also, at 8 months of age and over, SC of 17 cm-18 cm was observed from 9 kg BW and above. However, the correlation between SC and BCS was low and not significant. Semen analysis revealed the best semen quality for groups C and D bucks. In conclusion, we suggest that WAD bucks of 8 months and above, with at least SC between 17 cm–18 cm and of over 9 kg BW, could be used to breed does successfully on the farm.