1. Milk production of indigenous and crossbred dairy cattle in Senegal
Lotta Lassila, Patrick Jolly Ngono Ema, Karen Marshall, Ayao Missohou, Miika Tapio, Stanly Fon Tebug, Jarmo Juga.
Steps to Sustainable Livestock
12 – 15th January 2016, University of Bristol, UK
Faculty of Agriculture and Forestry Department of Agricultural Sciences
Lotta Lassila

2. Senegal Dairy Genetics (SDG)
Aim was to identify the best suited dairy cattle genotypes for the semi-intensive system in Senegal
Part of FoodAfrica Programme, coordinated by Natural Resources Institute Finland (Luke) and funded by the Ministry for Foreign Affairs of Finland
Led by the International Livestock Research Institute (ILRI), in partnership with the Interstate School of Veterinary science and Medicine of Dakar and the University of Helsinki
Faculty of Agriculture and Forestry Department of Agricultural Sciences
Lotta Lassila

3. Senegal Dairy Genetics (SDG)
Production recording from September 2013 to April 2015
220 households
Divided into two management groups
1447 cows
6082 test day records
Production recording started in September 2013
220 Households taking part in the project were divided into management groups by their average daily milk yield
Production recording was performed by 6 local enumerators. Enumerators visited the households once a month.
Daily milk yield was calculated as a sum of milk off-take from morning and evening milkings. During the 20 month recording period alltogether 6082 test day records were entered into the data base
Faculty of Agriculture and Forestry Department of Agricultural Sciences
Lotta Lassila

4. Breed groups
Cows were assigned to breed groups based on the farmer-given definition of breed
600 cows were also genotyped. These animals were asigned to breed groups by genotype information.
Largest breed group was native zebu cows, followed by zebu crosses with 25 to 50% of taurine blood and crosses between native and recent zebus.
Unfortunately, due to limited number of observations, pure bred taurines couldn’t be considered as their own group. They are here grouped with zebu crosses with at least 75% of taurine blood.
Faculty of Agriculture and Forestry Department of Agricultural Sciences
Lotta Lassila

5. Calving interval Management group better poorer Breed group days n
Native zebu
621* 68
634 84
50-75% Native zebu X 25-50% Recent zebu
555* 26
603 19
50-75% Native zebu X 25-50% Recent taurine
515* 52
658 23
0-25% Native zebu X % Recent taurine
546* 7
526 4
Calving interval was determined for cows with at least two known calving dates.
Average calving interval for all animals in four main breed groups was 594 days. Native zebus had longer calving interval than crossbreeds. However, there was statistically significant difference between breed groups only within better management group.
*Statistically significant difference (p=0,037) in calving interval between breed groups within better management group
Faculty of Agriculture and Forestry Department of Agricultural Sciences
Lotta Lassila

6. Length of lactation Management group better poorer Breed group days n
Native zebu
323* 51
404* 86
50-75% Native zebu X 25-50% Recent zebu
387 17
420 20
50-75% Native zebu X 25-50% Recent taurine
390 55
490
0-25% Native zebu X % Recent taurine
434 10 -
Length of lactation was determined using known calving date and farmer-given dry-off date.
Average length of lactation for animals in these four breed groups was 392 days. Statistically significant difference in length of lactation only for native zebus between two management groups. In poorer management group lactations were longer.
Average calving interval and length of lactation show that after lactation period cows are not lactating for over 200 days. This might partly explain the low percentage of cows being milked. (28%)
*Statistically significant difference (p=0,010) in length of lactation between management groups
Faculty of Agriculture and Forestry Department of Agricultural Sciences
Lotta Lassila

7. Milk yield of 305 days estimated with Wilmink function
Breed composition
Cows (n)
Milk yield of 305 days (liters) estimated with Wilmink function
100 % NZ1
473
402
75%NZ X 25%RZ2
113
554
50%NZ x 50%RZ
50%NZ x 50%RT3
171
1317
75%NZ x 25%RT
100%RT 37
1586
25%NZ x 75%RT
Test day records of cows with last known calving date were used to estimate the milk yield of 305 days.
Milk yield was estimated by fitting Wilmink function to the test day records of the whole breed group.
Native zebu cattle had the lowest milk yield. Crossbreeding increased milk yield and cows with 75 to 100% of taurine blood had the highest milk yield of 305 days.
However, crossbreeds of native and recent zebus had low milk yield compared to the crossbreeds with taurine blood.
Native zebus also had the largest difference in milk yield between the two management groups.
Crossbreeding increased milk yield more in the better management group. In poorer management group the difference between taurine crossbreeds and native zebus weren’t as high.
1Native Zebu 2Recently introduced taurine 3Recently introduced zebu
Faculty of Agriculture and Forestry Department of Agricultural Sciences
Lotta Lassila

8. Milk yield of 305 days estimated with Wilmink function
Test day records of cows with last known calving date were used to estimate the milk yield of 305 days.
Milk yield was estimated by fitting Wilmink function to the test day records of the whole breed group.
Native zebu cattle had the lowest milk yield. Crossbreeding increased milk yield and cows with 75 to 100% of taurine blood had the highest milk yield of 305 days.
However, crossbreeds of native and recent zebus had low milk yield compared to the crossbreeds with taurine blood.
Native zebus also had the largest difference in milk yield between the two management groups.
Crossbreeding increased milk yield more in the better management group. In poorer management group the difference between taurine crossbreeds and native zebus weren’t as high.
Faculty of Agriculture and Forestry Department of Agricultural Sciences
Lotta Lassila

9. Conclusions Crossbreeding increased milk yield
Crossbreeding native zebu with taurine
Importance of good management!
Production oriented farms use more crossbreeding?
Shorter calving interval to increase productivity
Shorter lactation period
As a conclusion crossbreeding zebus with taurine increased milk yield. Crossbreeding zebus didn’t have as much effect in milk yield.
Crossbreeding didn’t increase milk yield as much in poorer management group. Result emphasizes the importance of good management.
Native zebus had the biggest difference in milk yield between the two management groups. Most likely more production oriented farms also use more crossbreeding.
Productivity of milk production could be increased by shortening the calving interval. This way the percentage of adult cows not lactating might also be reduced.
Faculty of Agriculture and Forestry Department of Agricultural Sciences
Lotta Lassila

10. Thank you for your attention!
Faculty of Agriculture and Forestry Department of Agricultural Sciences
Lotta Lassila