Buffaloes contributed 61.1 percent to the total milk of Pakistan, which is world’s 4th largest milk
producing country. Protein requirements of buffalo appear to differ from those of cattle, yet
information on these nutritional requirements is limited. But establishing the protein and energy
requirements for animals is key point to lead the nutritionists for the optimum supply of these
nutrients. Thus, understanding the protein and N efficiency and an estimation of optimum protein
supply to buffalo is the need of time in terms of economics and animal production.
This study was conducted at “Dairy Animals Training and Research Center, University of
Veterinary and Animal Sciences, Ravi Campus, Pattoki” to check the performance of buffaloes in
response to increasing levels of dietary crude protein (CP) supplies (9.3, 10.0 and 11.5% of DM).
Design of the experiment was 3×3 Latin Square with two animals in each treatment, and total
duration of the study was 119 days. Different parameters were determined by using different but
recommended laboratory techniques. Milk parameters include milk yield, milk protein, fat, lactose
and density. Blood parameters include BUN, TG, NEFA and glucose. Fecal and urine sampling
and tests were performed using standard procedures to estimate the N efficiency and N balance.
Data was analyzed using GLM procedures of SAS.
DMI was similar among all the treatments with an average value of 14.36 kg/d. Milk production
increased from 7.75 to 8.04 kg/d in response to increase in dietary CP. Milk protein contents
increased from 3.86 to 3.92%, milk fat contents from 6.12 to 6.44 % and 4% fat corrected milk
from 10.05 to 10.92 kg/d, but milk lactose and milk density showed no response to increase in
dietary CP from 9.3 to 11.5% of DM. However, milk lactose yield increased, but body weight of
the animals decreased from 586 to 565 kg. Milk N efficiency also decreased from 21.9 to 18.7%,
SUMMARY
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but an increase in N intake observed with higher CP levels. Feed efficiency also increased from
0.54 to 0.56.
Blood metabolites showed a positive response to increase in dietary CP. Glucose, BUN and NEFA
increased with increase in protein supplies. While, TG contents were not affected by the
treatments. Milk N excreted as gram per day increased but decreased as percent of N intake,
resulting in reduced N efficiency. Urinary and fecal N excretion as gram per day also showed a
slight linear increase. Retention of N remained unaffected by the treatments but the values are
higher than that of cow, still a point reported to be attached with genetics of buffalo to retain more
N in the form of BUN as its reserves.
Increasing CP supplies improved both of the milk quantity and quality, and resulted in increased
BUN, glucose, NEFA and N intake, but decreased N efficiency. In this sense, when buffalo is
compared with cow, cow utilizes its dietary N in better way than buffalo. But when we estimate
lactation performance of both, at different low and high levels of protein supplies, buffalo performs
better at low level of dietary CP as compared to high protein diet. Current experiment served as
opportunity to recommend the minimum level of dietary CP for buffaloes without effecting the
animal production to minimize the cost and environment wastage.
CONCLUSIONS
In conclusion, increase in dietary protein supply results in improved quantity and quality of milk,
but meanwhile this increased supply causes a decrease in nitrogen use efficiency, because protein
supply above the required level starts to be excreted in urine and feces. And 11.5% CP of ration
DM is sufficient for Nili-Ravi buffalo at this production status.