Wednesday, December 20, 2017

Rumination and Activity in Dairy Calves up to 4 months of age

One of the research objectives in a study was to document rumination and activity among heifers that differed in milk replacer feeding rate, method of reducing milk replacer to weaning.

The groups were defined this way:

Group Name                     How much MR Fed       When and How Weaned                       TotalMRFe
Moderate - 6wk                   660g/day (1.5#)            1.5#/d 39 days, .75#/d 3 days                 60.8 #

High - 6 wk                      Up to 1.09kg/day             1.9# 4 days, 2.4# 31 days, 1.2# 7 days   94.1#

High - 8 wk                      Up to 1.09kg/day             1.9# 4 days, 2.4# 42 days, 1.2# 7 days    123.9#

Grad - 8 wk                      Up to 1.09kg/day              1.9# 4 days, 2.4# 35 days, 1.9# 4 days   116.2#
                                                                                   1.5# 4 days, 1# 4 days, 1/2# 4 days

Average time ruminating, eating and activity did not differ among treatments during days 38 to 56.

When I read this research report I expected to find higher rates of rumination among the "Moderate-6" group compared to the calves fed higher rates of milk replacer. Starter intake was measured. Rumination data were collected electronically from sensors on the calves. In general calves ruminated between 15 and 20 minutes per hour - the data show this behavior was spread out over nearly all 24 hours daily.

The calves fed the least amount of milk did start consuming starter grain about one week sooner than the other calves. However, these data seem to suggest that very little grain intake was required to stimulate rumination behavior. Note that the calves were bedded with long wheat straw.

When the milk feeding was reduced (High - 6 wk and High - 8 wk) - the calves were fed only in the morning during the weaning period - in the afternoon when these calves did not receive any milk feeding their activity level went up compared to the preweaning period.

Dennis, T.S. and Others, "Effect of milk replacer feeding rate, age at weaning, and method of reducing milk replacer to weaning on digestion, performance, rumination, and activity in dairy calves to 4 months of age." Journal of Dairy Science 101:268-278 January 2018

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