Milk yield and reproductive performances of lactating cows as affected by intakes of certain dietary macro minerals in Ethiopia
Livestock Research for Rural Development
Adami Tulu Agricultural Research Center, P.O. Box 35, Ziway, Ethiopia; Department of Animal Science, Faculty of Agriculture, Kasetsart University, Bangkok 10900, Thailand
This study was conducted to investigate the influences of dietary intakes of certain minerals on milk yield and reproductive performances of lactating cows fed on concentrate supplement with/without cottonseed cake and/or bole soil. Thirty-two pregnant Holstein Friesian cows with average body weight of 524±54 kg were blocked by their expected due date of calving as early (B1) and late (B2). Soon after calving animals were assigned in a randomized complete block design to one of the following four dietary treatments: concentrate alone (control) (C), 45% of the concentrate diet by weight substituted with cottonseed cake (C + CSC), concentrate plus 3% bole (lake soil) (C + Bole) and 45% of the concentrate substituted with cottonseed cake plus 3% bole (C + CSC + Bole) for 135 days of data collection. Statistically daily milk yield and FC milk yield were not ifferent among treatments. However, animals fed on the treatment diets of concentrate + CSC, concentrate + Bole and concentrate + CSC + Bole, produced 7.4, 16.3 and 18.2% respectively higher actual milk and 14.3, 24.2 and 25.7% respectively higher 4% fat corrected milk than the control group. Inclusion of bole soil alone as a mineral source or in combination with CSC supported higher daily actual and FC milk production than feeding concentrate diet with CSC alone. Days from calving to first estrus, days open and number of services per conception were not different among treatments. Nevertheless, Shorter intervals of days from calving to first estrus, days open and lowest number of services per conception were recorded for animals fed on concentrate diet with bole soil alone followed by those fed the control diet. Inclusion of 3% bole soil alone appeared to improve both milk yield and reproductive performances of dairy cattle.
Animalia; Bos taurus; Friesia; Micropus