Some productive and reproductive traits of cross-bred dairy cows in North Darfur

الملخص EN

The present study was conducted in North Darfur (Elfashir) during the period from March 2006 to April 2008 to assess the milk production and some reproductive traits of cross-bred dairy cows with Friesian (foreign inheritance over 50 %) under tropical conditions in North Darfur (El-Fashir).

Records of 123 cross-bred cows were studied in addition to some productive and reproductive traits for 30 lactating cows were also studied in three selected dairy farms: (farm-1, farm-2 and farm-3).

It was found that the total herd size was 153 head structured as; 47.7 %, 16.34 %, 17 %, 15.7 % and 3.18% lactating cows, dry cows, heifers, calves and bulls respectively.

The farms were visited weekly for recording daily milk production, and daily observations.The study revealed that the mean milk production per cow per day was 10.4±7, 11.85±8 and 10.2±9kg in farm-1, farm-2 and farm-3 respectively, with an overall average of 10.82±8 kg, with no significant differences (p0.05 > )(ANOVA) and the age at 1st calving was 31.4±3, 29.3±2.3 and 31.7±3.2 months in farm-1, farm-2 and farm-3 respectively, with overall average30.8±3.23 months with non-significant differences in one way ANOVA table and there was high correlation between milk production and age at 1st calving (p0.05 > ).

Whereas the open period and period were 76±18, 74.2±16 and 89±22 days as for open period and 75.6±6, 84.3±9 and 86±4 days for dry period in farm-1, farm-2 and farm-3 respectively, with overall average 80±16 days as open period and 82±8 days as dry period.

The persistency was ranging between 4th to 9th week, 3th to 10th week and 4th to 9th week in farm-1, farm-2 and farm-3 respectively.