A Study of Some Economic Traits of Indigenous Cattle and their Crossbreeds in Southern Bangladesh

The experiment was conducted on 69 cows to identify the quantitative variations of some economic traits of five genetic groups as $Local{\times}Friesian $ $F_1$, $Local{\times}Sahiwal$ $F_1$, Local (indigenous zebu type), $Local{\times}Sindhi $ $F_1$, and $Local{\times}Hariana$ $F_1$. The traits studied were age at weaning, age at first heat, age at first conception, services per conception, daily milk yield, lactation length, lactation yield and post partum heat period. The records on milking and reproduction performances of cows and heifers were obtained from farm register and by interviewing the farmers. It was observed that the lowest age at weaning, age at first heat and age at first conception were $5.37{\pm}0.24$, $27.17{\pm}1.72$ and $27.83{\pm}1.82$ months respectively in $Local{\times}Hariana$ $F_1$. Services per conception were lowest in $Local{\times}Sahiwal$ $F_1$ $(1.08{\pm}0.18)$ although not significantly (p>0.05) affected by farms, genetic groups and $farm{\times}genetic$ groups interaction. Average daily milk yield was highest in $Local{\times}Friesian$ $F_1$ $(5.81 {\pm}0.40 kg)$. Lactation length and lactation yield were highest in $Local{\times}Sahiwal$ $F_1$ ($299.38{\times}9.74$ days and $1863.00{\pm}141.00kg $ respectively). Average post partum heat period was lowest in $Local{\times}Sindhi$ $F_1$ ($3.19{\pm}0.38$ months). Least squares ANOVA showed that farm had significant (p0.05) effect of farm on services per conception, daily milk yield, lactation length and lactation yield, whereas genetic groups had a significant effect for all the traits under review except services per conception. $Farm{\times}genetic$ groups interaction was insignificant for all of the traits under consideration except age at weaning.