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Measurements of body conformation in sheep are of value in judging the quantitative characteristics of meat and also helpful in developing suitable selection criterion. Data on 349 Harnali sheep for body length (BL), body height (BH), heart girth (HG), paunch girth (PG), tail length (TL), head circumference (HC), ear length (EL), ear width (EW), face length (FL) and adult body weight (ABW) were analysed to study the relationship between linear body measurements and body weight. The mixed linear model with dam's weight at lambing as covariate was used to study the effect of non-genetic factors on body measurements and body weight. High estimates of heritability were obtained for BL, BH, HG, TL, HC, EL, EW, FL and ABW while moderate estimate was obtained for PG. The phenotypic correlations of BL, BH, HG, PG, HC and FL with ABW were positive and significant (0.32±0.04 to 0.59±0.08). The genetic correlations of HG, PG, HC and FL with ABW were 0.51±0.13, 0.42±0.19, 0.44±0.13 and 0.43±0.15, respectively. Various combinations of linear type traits to predict ABW were found to have coefficient of determination as high as 0.92. It is concluded that heart girth is the most important trait for estimation of live weight in sheep and the prediction equation is Body weight = -63.72 + 1.23 HG with R 2 = 0.87.

Aim:The present investigation was to study genetic characteristics of Harnali sheep with respect to growth performance and to estimate genetic parameters.Materials and Methods:The 22 years (1992-2013) data of growth traits of a 1603 synthetic population of Harnali sheep maintained at Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar, was utilized for this study. A mixed methodology with regression on their dam's weight was used to study the effect of non-genetic factors on growth traits. Heritability, genetic and phenotypic correlations were estimated using paternal half-sib analysis for body weight at various ages and average daily gain (ADG) for different growth periods.Result:The overall least squares mean of body weights recorded for birth weight (BW), weaning weight (WW), six months body weight (SMW), one yearling body weight (YBW), average daily gain from birth to 3 months (ADG1) and average daily gain from 3 to 12 months (ADG2) were 3.35±0.05 kg, 12.41±0.08 kg, 16.30±0.12 kg, 21.88±0.08 kg, 100.66±0.86 g/day and 35.07±0.39 g/day, respectively. The effects of year of birth significantly (p<0.01) influenced the BW, WW, SMW, YWB, ADG1 and ADG2. The effects of sex of lamb significantly (p<0.01) influenced the BW, WW SMW, YWB, ADG1 and ADG2. The effects of dam's weight at lambing significantly (p<0.01) influenced BW, WW, SMW, YWB, ADG1 and ADG2. No definite trend was observed over the years for the averages of body weight and gain. The heritability estimates of BW, WW, SMW, YBW, ADG1 and ADG2 were 0.40±0.05, 0.38±0.05, 0.45±0.06, 0.29±0.05, 0.40±0.06 and 0.33±0.02, respectively. The male lambs were significantly heavier than females at all stages of growth. The heritability estimates were moderate for all the growth traits and high genetic correlations of BW and WW with SMW were found.Conclusion:Due to high heritability and positive correlations of SMW with other body weights and daily gain, it was concluded that selection on the basis of SMW would be the best approach to improve growth performance in Harnali sheep.

Data on growth, reproduction and wool traits of 1603 Harnali sheep maintained at Lala Lajpat Rai University of Veterinary and Animal Sciences, Hisar over a period of 22 years were utilized for genetic analysis. The overall least squares mean for birth weight (BW), weaning weight (WW), six month body weight (SMW), age at first lambing (AFL), weight at lambing (WL), average lambing interval (ALI), greasy fleece weight (GFW), staple length (SL) and Fibre diameter (FD) were estimated as 3.35±0.02 kg, 12.41±0.08 kg, 16.30±0.12 kg, 707.05±2.07 days, 26.91±0.10 kg and 402.85±2.40 days, 1.62±0.02 kg, 5.65±0.03 cm and 25.85±0.07 µ, respectively. The effect of year of birth, sex of lamb and dam's weight at lambing were significant for all growth traits. The effect of year of birth and dam's weight at lambing were significant for all reproduction traits and GFW. No definite trend was observed over the years for body weights and reproductive traits. The effect of sex was significant for early growth traits. The heritability estimates were moderate for all the growth traits with high genetic correlations of BW and WW with SMW. Reproduction traits had lower estimates of heritability which indicated presence of lower additive genetic variance for these traits. Heritability estimates for studied wool traits were moderate to high. Positive genetic and phenotypic correlation of BW and WW with six month body weight and grease fleece weight indicated that selection for six month body weight would increase body weight and grease fleece weight.