Livestock Studies 1969, Vol 9, Num, 1-2     (Pages: 001-014)

The result obtained from Native Gray x Brown Swiss cattle crossbreeding experiments

H. Saim KENDİR

- The purpose of this study is to compare first upgrades (G1) obtained from Native Gray x Brown Swiss crossbreeding with F1 and Native Grey controls. This crossbreeding experiment is going on in Çifteler State Farm Since 1953.

Records on 72 NG, 62 F1 and 66 G1 calves showed that the average birth weight (average of males and females) is 23.2 kg in NG, 30.5 kg in F1 and 34.5 kg in G1 the group differences are all statistically significant in 0.99 significance level. Records on 66 NG, 57 F1 and 64 G1 calves showed that the average weight gain in first six months (average of males and females) is 103.9 kg in NG, 117.4 kg in F1 and 123.3 kg in G1 the difference between first two groups is statistically significant in 0.99 level.

Records on 24 NG, 16 F1 and 36 G1 cows showed that the average milk yield in first lactation (305 day, not corrected for age) is 1268 kg in NG, 1740 kg in F1 and 1933 kg in G1 the group differences are all statistically significant in 0.99 level.

Records on 39 NG, 14 F1 and 51 G1 cows showed that the calving percentage in first calving season is 79.5 % in NG, 78.6 % in F1 and 78.4 % in G1 the group differences are not statistically significant.

Records on 182 NG, 86 F1 and 140 G1 calves showed that the mortality rate up to 18 months is 12.6 % in NG, 12.8 % in F1 and 5.0 % in G1 the differences between G1and the other groups are statistically significant in 0.99 level. Keywords :