Article ID Journal Published Year Pages File Type
10978076 Journal of Dairy Science 2013 12 Pages PDF
Abstract
The challenges associated with group-housed dairy cows include within-herd variability in nutrient consumption and milk production, which may be related to feeding management. The objective of this observational study was to examine the association of herd-level feeding management factors, feed sorting, and milk production. Twenty-two freestall herds with an average lactating herd size of 162 ± 118 cows, feeding total mixed rations, were each studied for 7 consecutive days in summer and winter. In cases of multiple feeding groups within a herd, the highest producing group of cows with an even distribution of days in milk and parity was selected for this study. The average group size studied was 83 ± 31 cows. The average study group consisted of cows 187 ± 47 days in milk, with a parity of 2.3 ± 0.6, consuming 24.3 ± 2.6 kg of dry matter, with an average group-level yield of 34.3 ± 6 kg of milk/d, 3.7 ± 0.3% milk fat, and 3.2 ± 0.18% milk protein. Milk production parameters, including yield, fat, and protein, were recorded through regular Dairy Herd Improvement milk testing. A survey of feeding management practices and barn characteristics was administered on each farm. The amounts of feed offered and refused were recorded and sampled daily to assess dry matter intake (DMI) and particle size distribution. Feeding twice per day compared with once per day was associated with an average increase of 1.42 kg of DMI, 2.0 kg of milk yield, and less sorting against long ration particles (>19 mm). Every 2% group-level selective refusal (sorting) of long particles was associated with 1 kg/d of reduction in milk yield. A 10 cm/cow increase in feed bunk space was associated with a 0.06-percentage-point increase in group-average milk fat and a 13% decrease in group-average somatic cell count. These results support that herd-level management practices to promote feed access, such as increased feeding frequency and bunk space, may improve DMI and promote more balanced nutrient intake and greater milk production.
Related Topics
Life Sciences Agricultural and Biological Sciences Animal Science and Zoology
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