Affordable Access

Publisher Website

Variations in Yield of milk under the Penkeeping System in Brazil

Authors
Journal
Journal of Dairy Science
0022-0302
Publisher
American Dairy Science Association
Volume
31
Issue
3
Identifiers
DOI: 10.3168/jds.s0022-0302(48)92197-3
Disciplines
  • Social Sciences

Abstract

Summary Records from a large farm in the Zona da Mata in Brazil were studied to learn about conditions which affect milk production under the penkeeping system. Production varied significantly from year to year. Part of this is ascribed to an upward trend with time, but the statistical significance of that trend is not wholly assured. Some of the yearly means deviated rather widely from that trend. Season of year had significant but rather small effects on the daily yield. The higher yields were toward the middle and end of the rainy season, while the lower ones were late in the dry season. Production reached a maximum some time around 40 to 50 days after calving. Thereafter it declined in almost a straight line. The sex ratio showed a slight but statistically significant excess of males. The year-to-year deviations of the sex ratio from the general mean were not statistically significant. Heritability of individual differences in milk yield under these conditions seems moderately high.

There are no comments yet on this publication. Be the first to share your thoughts.

Statistics

Seen <100 times
0 Comments

More articles like this

Variations of mammary artery blood flow and milk y...

on Zeitschrift für Tierphysiolog... January 1980

Interannual variations of rainfall and corn yields...

on Agricultural and Forest Meteor... Jan 01, 1997

Variations in the carbon isotope composition and p...

on Organic Geochemistry Jan 01, 1986
More articles like this..