Feeding Systems with Legumes to Intensify Dairy Farms - cgiar

Table 3. Average milk production of dual-purpose cows grazing native and
associated pastures during the rainy seasons of 1997-1999 (Esparza,
Costa Rica).
Year
Milk production on two types of pasture
(kg/cow per day) a
Nativeb Brachiaria brizantha + Centrosema brasilianum
1997 8.6 9.3
1998 7.5 7.9
1999 7.6 8.1
Average* 7.9 a 8.4 b
a. Average of 26 milking cows.
b. Mainly B. ruziziensis.
* Averages in the same row followed by the same letter did not differ significantly (P = 0.0246) using
the Student’s (t) test.
The average increase in milk production during the three years of the
evaluation in the sole cropped pasture as compared with the native grass
was 3.8%, whereas the increase for cows grazing the associated pasture was
6.3%. Besides this increase in milk production, producer’s income also
increased because of the larger amount of milk sold.
Differences in milk production between sole cropped and associated
pastures were 250 g/animal per day, which agrees with results found by
Ullrich et al. (1994) who worked with dual-purpose cows grazing B.
decumbens alone and associated. At the Escuela Centroamericana de
Ganadería (ECAG) in Atenas, Costa Rica, milk production of Jersey dairy
cows increased 9% when grazing a B. decumbens + A. pintoi cv. El Porvenir
pasture, as compared with cows grazing the sole cropped pasture and
offered a commercial concentrate as supplement (Romero and González,
1998). These results are similar to those found in this study, despite these
being dairy cows well known for their milk production that received
concentrate. This confirms once more the beneficial effect of the legumes on
milk production.
Besides the benefits in milk production when improved pastures are
used, there is a significant increase in milk production/hectare as shown in
Table 4.
Cipagauta et al. (1998) found that half-bred Holstein x Zebu dairy cows,
grazing B. decumbens alone and associated with legumes (20% of the
pasture) in the Amazon piedmont of Caqueta, Colombia, produced 52%
more milk/ha on the sole cropped pasture as compared with the native
pasture, and 94% more milk on the associated pasture. The estimated milk
production/ha of cows grazing associated pastures differed by 23% from
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