E.A. Mukisira
National Agricultural Research Station
P.O. Box 450, Kitale, Kenya
Introduction
Methodology
Results
Discussion
Conclusion
Acknowledgements
References
Abstract
Two groups each of five lactating Friesian cows were supplemented with varying proportions of lupine and maize meal. -The five rations contained lupine and maize meal percent proportions, respectively as follows: A (100,0), B (75,25), C (50,50), D (25, 75) and E (0,100). The milk yield and its quality for each cow were determined along with supplemental intake and percent crude protein (CP).
The rations had no effect on the milk butterfat, solids-not-fat, calcium, phosphorus and total solids. Animals on ration D(17.4% CP) had the highest milk yield of 15 kg/day and an intake of 3.9 kg/day. Ration E with 10.0% CP gave the highest intake at 4.0 kg/day with a yield of 13.4 kg Fat Corrected Milk (FCM) per day. This production was superior to that recorded for rations A, B and C. Invariably, ration A with the highest percent CP of 32.7 gave the least intake of 2.0 kg/day and the least milk yield of 10.3 kg FCM/day. This unexpected observation was attributed to some inherent factor in the lupine meal that negates intake with the resultant effect of lowering milk yield.
In most smallholder dairy systems in the high potential areas of Kenya, provision or enough feed to lactating animals is a major constraint to production. Fresh herbage and crop residues fed during the dry season are generally of low quality and hence contain substandard energy and protein levels that can hardly meet maintenance requirements of lactating cows. In these circumstances, lupine grain could prove suitable as a feed supplement (Kenney, 1980). As well as having a comparatively high protein content (over 30% in dry matter), lupine is easy to feed and convenient to store for a considerable period of time.
Commercial feeds manufactured and compounded by some feed industries form the bulk of the supplements in dairy enterprises. These are expensive for the average Kenyan farmer, hence the need to have supplement substitutes that can provide adequate energy and protein levels that do meet production requirements of lactating animals. The cost of lupine and its availability and value as a feed is such that it could be mixed with other cereal grains particularly maize for supplementary feeding. A grain with such a high protein content could be suitable as a supplement for lactating cows for which a diet with a protein content of about 16% is recommended for maximum production (NRC, 1978).
Protein ingredients in most supplements are the most expensive and hence pose major problems in most on-farm rations; this is because humans compete for the same for food. This, however, is not the case with lupine which is currently being used solely as feed. This study which involved the feeding of lupine (Lupinus albus cv Ultra) and maize meal was designed to solve the supplementation problem of nearly 20,000 farmers (Stotz, 1983) located mostly in the Kenyan highlands.
Lupine, however, has shortcomings which include lupinosis known to cause liver disfunction through the damaging of liver tissues. The dangers of lupinosis have not been reported when seed is fed as a concentrate to ruminants, but was reported on the non-ruminants by Godfrey et al. (1985) and Wanjala (1979).
Little work has been reported on the performance of dairy cows when supplemented with lupine alone or when incorporated in high energy diets. The primary objective of this trial was to study the effect of supplementing varying proportions of maize and lupine meal on the milk yield of lactating Friesian cows.
The lactating Friesian cows, divided into two groups of five, were selected based on stage of lactation (animals in second or third lactation being preferred), average yield of Fat Corrected Milk (FCM), days postpartum and liveweight. The cows were then randomly assigned to five treatments containing varying proportions of maize and lupine meals. The percentage proportions of the two ration ingredients were A (100,0), B (75,25), C (50,50), D (25,75) and E (0,100) of lupine and maize meal, respectively.
A change-over design in two 5 x 5 latin squares was used in the study. For each group of cows there was an adjustment period and a collection period of 14 days and 7 days, respectively. The cows were grazed on good quality Chloris gayana (Rhodes grass) pasture with supplementation being done daily during milkings at 08:00 and 16:00 hours. About 4.0 kg of each ration was supplemented daily to each animal.
For each cow, the quantity of FCM produced daily was recorded. Samples of milk were taken twice a week during the collection period. The Gerber method was used in the determination of percent butterfat, on a portion of the sample, immediately after milking. The remaining sample was bulked for each cow within each period and later analysed for milk protein (CP), solids-not-fat (SNF), total solids (TS), calcium and phosphorus.
Milk Yield and Quality Assessments
A summary of the average milk yield and its quality values are shown in Table 1. Milk yield expressed on a fat corrected basis was highest (15.0 kg/day) for cows supplemented with treatment D followed with treatment E which gave 13.4 kg FCM/day. Non-significant differences (P>0.05) were observed among treatments A, B and C (10.3, 11.5, 10.5 kg FCM/day, respectively). The milk protein from cows fed on treatment ration B and C were higher (P<0.05) than that of milk from cows fed on treatments D and E. Other milk quality factors (SNF, BF, TS, Ca, P) did not show any differences (P>0.05) among treatments.
Table 1. Summary of average milk production and milk quality values.
|
Experimental rations |
Milk yield (kg) |
Milk quality (%)d |
|||||
|
CP1 |
BF² |
SNF³ |
Ca |
P |
TS4 |
||
|
A |
10.3c |
27.9a |
4 0 |
7.2 |
.88 |
.95 |
11.2 |
|
B |
11.5c |
26.7b |
3.9 |
7.4 |
.91 |
.89 |
11.3 |
|
C |
10.7c |
25.8b |
4.0 |
7.4 |
.86 |
.88 |
11.4 |
|
D |
15.0a |
24.5c |
4.1 |
7.3 |
.87 |
.86 |
11.4 |
|
E |
13.4b |
24.1c |
3.7 |
7.3 |
.91 |
.87 |
10.9 |
|
SE |
0.5 |
0.3 |
0.1 |
0.1 |
.02 |
.03 |
0.1 |
|
LSD |
1.4 |
0.9 |
NS |
NS |
NS |
NS |
NS |
|
CV % |
8.4 |
2.5 |
6.8 |
1.8 |
5.4 |
6.5 |
6.8 |
abc Means in the same columns with different superscripts are significantly different.
d Averaged for each ration between experimental periods.
1 Crude protein
2 Butterfat
3 Solids-Not-Fat
4 Total solids
Supplement Quality Analyses and Intake
The per cent CP content and intake values of the various ration formulations are presented in Table 2. Ration A had the highest CP (P<0.05) value of 32.7 but the least intake (P<0.05) of 2.0 kg/day. The results showed a declining trend in intake with increasing ration CP content.
Table 2. Crude protein and intake values of the concentrate rations.
|
Experimental rations |
% CP |
Intake (kg/day) |
|||||
|
Periods |
|||||||
|
I |
II |
III |
IV |
V |
Mean |
||
|
A |
33.5 |
32.9 |
34.1 |
31.9 |
31.1 |
32.7a |
2.0c |
|
B |
27.9 |
26.9 |
25.9 |
28.1 |
27.2 |
27.2b |
3.2b |
|
C |
24.6 |
23.9 |
21.9 |
23.2 |
21.1 |
22.9c |
3.5a |
|
D |
18.6 |
16.8 |
16.9 |
17.2 |
17.6 |
17.4d |
3.9a |
|
E |
9.7 |
9.6 |
10.1 |
10.5 |
9.9 |
10.0e |
4.0a |
|
S.E. |
0.4 |
0.2 |
|
LSD .05 |
1.2 |
0.6 |
|
C.V. % |
4.2 |
13.0 |
abcde Means in the same columns with different superscripts are significantly different (P<0.05).1 Values have been averaged for each ration between periods.
The results indicate that ration D with a percent CP of 17.4 and an average daily intake of 3.9 kg/day produced favourable milk yields. It would thus appear that this ration had optimal nutritive status to increase and sustain high milk-yield levels. Cows fed on pure lupine showed some reluctance in consuming it this being reflected in occasional observation of nil daily intakes particularly with decreasing levels of crude protein in the rations. This observation appears to conflict with the generally accepted concept that crude protein is the one nutritive factor that does consistently increase intake as evidenced by studies conducted by Ammerman et al. (1972), Mukisira and Hembry (1985).
Inference from the observations made supposes that a factor inherent in the lupine meal could be responsible for the unexpected low levels of supplemental intake with increasing ration percent CP values. There is some possibility that alkaloids result in an undesirable taste to the cows. Inclusion of maize meal in the rations tends to decrease the bitter taste with the resultant effect of increasing supplemental intake and to some extent animal performance. Considering this argument cows supplemented with pure maize meal had the highest intake of 4.0 kg/day albeit their average milk yield was inferior to that from cows fed treatment D. This could be attributed to the lower percent CP value in the pure maize meal ration.
Data drawn from this trial show that ration D containing 75% maize and 25% lupine meals is desirable since animals on this treatment produced the highest milk yields. It also manifested fairly high intakes. Treatment rations with high lupine inclusions tended to have low intakes. This was attributed to the presence of alkaloids which impart an undesirable taste to lupine meals. It is hoped that the next stage of the study will investigate the actual alkaloid levels in the sweet lupine and to some extent establish its lupinosis effect, if any, on the liver cells of yearling steers.
The author would like to thank Mr. C.W. Mwendia for his technical advice when writing up the paper and R.E. Kamidi for the statistical analyses. Appreciation is also extended to the Deputy Director of Research of the Kenya Agricultural Research Institute for permission to publish these results. Last but not least, to Mr. D.K. Muthoka, Director, National Agricultural Research Station, Kitale for his assistance in the entire study.
Ammerman, C.B., Verde, G.J., Moore, J.E., Burns, W.C. and Chicco, C.F. 1972. Biuret, urea and natural proteins as nitrogen supplement for low quality roughages for sheep. Journal of Animal Science 35:121-124.
Godfrey, N.W., Mercy, A.R., Emms, Y. and Payne, H.G. 1985. Tolerance of growing pigs to lupin alkaloids. Australian Journal of Experimental Agriculture 25:791-795.
Kenney, P.A. 1980. Intake and production of lambs fed rations of oats with varying amounts of lupine. Proceedings of the Australian Society of Animal Production 13:253-256.
Mukisira, E.A. and Hembry, F.G. 1985. A nutritional assessment of warm season forages by in vivo and in vitro techniques. Proceedings of the fourth small ruminant CRSP. Kenya Workshop, pp. 226-230.
Nutritional Requirements Council. 1978. The nutritional requirements of domestic animals. pp. 36-37.
Stotz, D. 1983. Production techniques and economics of smallholder livestock production systems in Kenya Ministry of Livestock Development. Animal Production Division, Nairobi. In: Farm Management Handbook of Kenya. Volume IV, p.48.
Wanjala, B.W. 1979. An introduction to lupin cultivation. Kenya Farmer. January. English Press, Nairobi. p.17.
