A cross sectional study was conducted during October and November 2006 on 69 smallholder dairy farms with lactating cows in Mvomero and Njombe districts Tanzania, to determine the prevalence of mastitis and to assess the milk quality on the study farms. Clinical mastitis was investigated using clinical changes of udder and milk at animal level. Cow-side California Mastitis Test (CMT) and microbiological cultures were used to assess subclinical mastitis at quarter level. Milk quality was determined on bulk milk samples at herd level using alcohol and acidity tests, butter fat content, total solids, ash content as well as Delvotest® for antimicrobial residues. Overall prevalence of clinical mastitis at herd level in both districts was 21.7 % (n = 69). Based on CMT, prevalence of subclinical mastitis at animal level was 51.6 % (n = 91). Prevalence of bacterial isolates at animal level was 35.2 % (n = 91) while for fungal it was 16.7 % (n = 90). Based on CMT results, prevalence of subclinical mastitis at quarter level was 30 % (n = 353), while for bacteria and fungi it was 16 % and 6 % respectively. Contamination of milk with antimicrobial residues was 4.5 % (n =67). The milk quality parameters for most of the milk samples were within acceptable levels. Findings in this study have demonstrated high prevalence of subclinical mastitis that may contribute to low productivity of dairy cattle in both districts. About 20 % of CMT subclinical cases had no involvement of microbial pathogens that suggested the need for minimal interventions with antimicrobial agents. These findings call for use of udder disinfectants and improved milking hygiene as intervention strategies to control mastitis on the smallholder dairy farms in Tanzania

No abstract

No abstract

No abstract

Two experiments were conducted in the Makambako division of the southern highlands of Tanzania to investigate the effects of regrowth period, season and harvesting frequency on the yield and nutritive value of Chloris gayana. The first experiment was conducted in 2002 in a 4X2 factorial arrangement in a complete randomised block design with six replications. The treatments were period of regrowth (three, six, nine and 12 weeks) and season (early wet season January-March and late wet season April-June). The second experiment was conducted in 2003 in a complete randomised design with six replications. The treatments were four cutting frequencies (three, six, nine and 12 weeks). In Experiment 1, the dry matter yield (DMY) ranged from 1.09-7.99t ha -1 and from 0.97-3.53t ha -1 (P < 0.05), while the crude protein (CP) content ranged from 13.9-8.25% and 16.09-9.85% (P < 0.05) in the early and late wet seasons, respectively. In vitro dry matter digestibility (IVDMD) and metabolisable energy (ME) declined faster with increasing periods of growth in the early than in the late wet season. ME ranged from 9.21-7.29MJ kg -1 DM (P < 0.05) and 8.02-7.87MJ kg -1 DM (P > 0.05) in the early and late wet seasons, respectively. For Experiment 2, the nine-and 12-week cutting frequencies did not differ (P > 0.05) in terms of cumulative DMY (19.07 versus 18.93t ha -1 ) but produced nearly twice as much as the three-and six-week cutting frequencies (10.18 and 8.32t ha -1 ). CP, IVDMD and ME decreased while neutral detergent fibre (NDF) increased with decreased cutting frequency. The results of the present study suggest that the optimal balance of dry matter yield and nutritive value of C. gayana at Makambako is reached at the ninth week of regrowth. Regardless of season, dairy farmers in this area who are feeding pure C. gayana must provide energy supplement to their dairy cows.