| Autor: |
C.E. Coppock, N.E. Smith, W.G. Merrill, G.R. Ufford |
| Rok vydání: |
1978 |
| Předmět: |
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| Zdroj: |
Journal of Dairy Science. 61:1138-1145 |
| ISSN: |
0022-0302 |
| DOI: |
10.3168/jds.s0022-0302(78)83697-2 |
| Popis: |
Both first lactation and older Holstein cows were assigned to either a one group or a two group system of feeding and management. Animals in the one group system were fed a complete ration of 56% corn silage:44% concentrate, dry matter. In the two group system, cows were fed a similar ration in early lactation and at higher milk production and then shifted to a ration of 84% corn silage:16% concentrate at lower production. Dry matter intakes of corn silage and concentrates were 9.9 and 7.8 kg/cow per day for the one group system, and 11.5 and 5.5 kg/cow per day for the two group system. Cows in the one group system averaged .6kg milk/cow per day greater yield than cows in the two group system. The average decline in milk yield the 1st wk after group change was 2 kg/cow per day. Milk loss persisted longer in older cows than in first lactations. Magnitude of loss in milk was not related to stage of lactation but to milk production at the time of change. Although milk production was greater in the one group than the two group system, income over feed costs were $30/cow per year greater for two groups, primarily because of reduced intake of concentrate. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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