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THE EFFECT OF GESTATION ON THE RATE OF DECLINE OF MILK SECRETION WITH THE ADVANCE OF THE PERIOD OF LACTATION.
S Brody1, A C Ragsdale, C W Turner
1Department of Dairy Husbandry, University of Missouri, Columbia.
The Journal of General Physiology
|October 30, 2009
Summary
Milk production decline in lactating cows follows a chemical reaction pattern. Fetal growth also reduces milk yield by demanding nutrients, impacting dairy farming efficiency.
Area of Science:
- Dairy Science
- Biochemistry
- Animal Physiology
Background:
- Milk secretion naturally declines during lactation.
- Pregnancy in cows also affects milk production levels.
Purpose of the Study:
- To investigate the biochemical and physiological mechanisms underlying milk production decline in lactating and pregnant cows.
- To model the decline in milk secretion using chemical reaction kinetics.
Main Methods:
- Analysis of milk production data over the lactation period.
- Correlation of milk yield decline with animal weight gain during gestation.
Main Results:
- Milk secretion decline during lactation follows a monomolecular chemical reaction, with monthly production being a constant percentage (94.77%) of the previous month.
- Pregnancy-induced decline in milk flow is linked to the increasing weight of gestating animals, indicating fetal nutrient demand.
Conclusions:
- Milk secretion appears to be limited by a chemical reaction initiated at parturition, dependent on substrate concentration.
- Fetal growth significantly contributes to the reduction in milk yield during pregnancy due to nutrient competition.
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