Agriculturae Conspectus Scientificus, Vol 64, No 1 (1999)

Heritability Estimates of Type Traits Scored by Linear Scoring "System '97"

Marijan POSAVI, Miroslav KAPŠ, Ino ČURIK, Aleksandar KLJUJEV

Pages: 59-65

Summary


The objective of this study was to estimate genetic and environmental variances and heritabilities for 19 linear type traits in Croatian Simmental cattle. For this purpose data on 1370 Simmental heifers (daughters of 119 bulls) were analyzed. Type traits of heifers were linearly scored during 1997 year using method "System 97". Rump height, back length, length and width of rump, body depth and heart girth were measured by tape or stick. Other traits were scored linearly using ninepoint scoring range. Variances and heritabilities were estimated by the restricted maximum likelihood method (REML) for an Animal Model including age at scoring, stage of lactation and classifier as fixed effects and animal as a random effect. High heritability estimates of 0.50, 0.43 and 0.42 were obtained for teat placement, length of rump and rear legs (side view), respectively. The moderate heritability estimates (0.15-0.30) were found for back length, rump height, rump width, body depth, muscularity, rump (side view), hock joint thickness, height of hoofs, pasterns, suspensory ligament, teats length and teats thickness. Low heritability estimates were found for heart girth, fore udder length, rear udder height and udder depth. Some of the estimated heritabilities were lower than those reported by other authors. The reason for that could be because of inconsistent scoring criteria of classifiers or small data set analyzed in the present study.

Keywords


Simmental cattle; Linear scoring; Heritability

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