This chapter reviews and analyses the production parameters reported in the non-traditional ranching systems and smallholder dairy systems. Too few studies are available to permit detailed analysis by zone or subregion, so results were broken down only when this was possible and seemed reasonable.
Table 29 (and Appendix 12) presents reported production parameters of cattle in the beef systems of the arid/semi-arid and subhumid/humid zones - areas with a mean rainfall less and greater than 1 000 mm per annum respectively. The mean calf mortality risks in beef systems located in the arid/semi-arid zones (10.2 percent) and in the subhumid/humid zones (10.1 percent) are similar. The mean replacement mortality risks are 10.0 percent and 7.8 percent, while the mean cow mortality risks are 5.7 percent and 6.2 percent in beef systems located in the arid/semi-arid and the subhumid/humid zones respectively. The mean age at first calving for beef systems in the subhumid/humid zones is 41 months, while no values are available for the arid/semi-arid zones. The calving rates in beef systems in the arid/semi-arid and subhumid/humid zones are similar, at 76.6 percent and 76.2 percent respectively. The mean weight of cows (414 kg) and bulls (495 kg) in the arid/semi-arid zones is higher than the mean weight of cows (309 kg) and bulls (440 kg) in the subhumid/humid zones.
Table 29. Mean production parameters of beef systems in sub-Saharan Africa by agro-ecological zone
|
Parameter |
Arid/semi-arid |
Subhumid/humid |
||
|
Calf mortality risk (%) |
10.2 |
(17) |
10.1 |
(13) |
|
Female/male replacement mortality risk (%) |
|
n.r.2 |
7.8 |
(3) |
|
Cow mortality risk (%) |
5.7 |
(7) |
6.2 |
(5) |
|
Age at first calving (months) |
|
n.r. |
41.0 |
(2) |
|
Calving rate (%) |
76.6 |
(31) |
76.2 |
(17) |
|
Milk offtake per lactation (kg) |
185.0 |
(6) |
750.0 |
(2) |
|
Weight of mature cow (kg) |
414.0 |
(12) |
309.0 |
(4) |
|
Weight of mature bull (kg) |
495.0 |
(2) |
440.0 |
(2) |
1 Numbers in brackets represent number of studies
2 n.r. = no reference
The reported production parameters for dairy systems are presented in Table 30[10] (and Appendices 12 and 13). The mean calf mortality risks reported in the smallholder dairy systems are 12.4 percent and 15.9 percent for female and male calves respectively, while the mean replacement mortality risks are 9.1 percent and 22.4 percent (only one study) for females and males respectively. The mean reported cow mortality risk in smallholder dairy is 5.2 percent, while the mean age at first calving is 48 months, the mean calving rate is 71.9 percent and the mean milk offtake per lactation is 2 050 kg. The mean weight of cows and bulls in smallholder dairy systems is 320 kg and 450 kg.
The reported mean calf mortality risk in large-scale dairy systems is 8.1 percent and 6.4 percent for female and male calves respectively (Table 30). The mean reported replacement female mortality risk in these systems is 1 percent[11] (one study only), while the mean cow mortality risk is 4 percent. The mean age at first calving is 33.4 months and the average calving rate is 87.2 percent. The mean milk offtake per lactation in large-scale dairy systems is 3 911 kg, with a median of 3 195 kg and a range of 2 112 kg to 6 715 kg. The mean weight of mature cows and bulls is 414 kg and 450 kg respectively.
Table 30. Mean production parameters of dairy systems in sub-Saharan Africa
|
Parameter |
Small-scale dairy |
Large-scale dairy |
||
|
Female calf mortality risk (%) |
12.4 |
(16) |
8.1 |
(6) |
|
Male calf mortality risk (%) |
15.9 |
(15) |
6.4 |
(5) |
|
Female replacement mortality risk (%) |
9.1 |
(4) |
1.0 |
(1) |
|
Male replacement mortality risk (%) |
22.4 |
(1) |
1.0 |
(1) |
|
Cow mortality risk (%) |
5.2 |
(6) |
4.0 |
(4) |
|
Age at first calving (months) |
48.0 |
(1) |
33.4 |
(1) |
|
Calving rate (%) |
71.9 |
(22) |
87.2 |
(13) |
|
Milk offtake per lactation (kg) |
2 055.0 |
(25) |
3 911.0 |
(21) |
|
Weight of mature cow (kg) |
320.0 |
(5) |
414.0 |
(5) |
|
Weight of mature bull (kg) |
450.0 |
(1) |
450.0 |
(1) |
1 Numbers in brackets represent number of studies
|
[10] In the case of
smallholder dairy systems, production parameters for the highlands of East
Africa only are presented because of the importance of these systems in this
subregion (Jahnke, 1982; Wilson, 1995) and the scarcity of reported values from
other subregions. Reported parameters for large-scale enterprises are from
studies in East and southern Africa covering all zones. [11] Replacement mortality risks are rarely reported. |
