Kanuya N.L., Matiko M.K., Nkya R., Bittegeko S.B.P., Mgasa M.N., Reksen O., Ropstad E.
Department of Veterinary Surgery and Theriogenology, Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania; Department of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, Oslo, Norway
Kanuya, N.L., Department of Veterinary Surgery and Theriogenology, Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania; Matiko, M.K., Department of Veterinary Surgery and Theriogenology, Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania; Nkya, R., Department of Veterinary Surgery and Theriogenology, Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania; Bittegeko, S.B.P., Department of Veterinary Surgery and Theriogenology, Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania; Mgasa, M.N., Department of Veterinary Surgery and Theriogenology, Faculty of Veterinary Medicine, Sokoine University of Agriculture, Morogoro, Tanzania; Reksen, O., Department of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, Oslo, Norway; Ropstad, E., Department of Production Animal Clinical Sciences, Norwegian School of Veterinary Science, Oslo, Norway
The objectives of this study were to assess changes in nutritional status/body condition score, percentage pregnancy and calving rate in Zebu cows and to establish the relationship between body condition score loss and postpartum interval to resumption of ovarian activity. A total of 198 cows and postpubertal heifers of the Tanzanian Shorthorn Zebu kept under a traditional management system were randomly selected from 200 smallholder herds. Factors investigated during bi-weekly visits include body condition score (BCS), heart-girth circumference, milk yield and reproductive status of the animals, pregnancy/non-pregnancy and cyclicity/non-cyclicity. Local weather conditions and dates of occurrence of other reproductive events such as calving were also recorded. Calvings occurred all year round but with a strong seasonal distribution characterized by annual peaks observed between April and July. The annual calving pattern was closely related to rainfall, with peak precipitation occurring a few months before peak calving. The overall percentage pregnancy varied from 30% to 50% throughout the year. Postpartum cows exhibited minimum mean BCS and heart-girth circumference 12-14 weeks after calving, and cows with BCS loss >1 point exhibited the longest time interval from calving to onset of ovarian activity. © 2006 Springer Science + Business Media B.V.
rain; animal; animal food; article; body constitution; cattle; estrus cycle; female; nutritional status; physiology; pregnancy; pregnancy rate; puerperium; reproduction; season; Tanzania; time; Animal Nutrition Physiology; Animals; Body Constitution; Cattle; Estrous Cycle; Female; Nutritional Status; Postpartum Period; Pregnancy; Pregnancy Rate; Rain; Reproduction; Seasons; Tanzania; Time Factors; Animalia; Bos indicus