Record Details

The relationship of initial weight to growth rate in preweaning pigs

ScholarsArchive at Oregon State University

Field Value
Title The relationship of initial weight to growth rate in preweaning pigs
Names Keeler, Joseph Lambert (creator)
England, David C. (advisor)
Date Issued 1964-07-07 (iso8601)
Note Graduation date: 1965
Abstract Growth data compiled in this study were collected by using
pigs farrowed during the fall, 1963 and spring, 1964 farrowing seasons
of the Oregon State University swine herd. Thirty-seven trios
of light-, medium- and heavy-birth-weight suckling pigs were used to
determine the effect of birth weight on subsequent rate of gain under
conventional preweaning management conditions. Thirteen pairs of
light- and moderate-birth-weight pigs reared from an initial average
weight of 8.5 pounds were used to determine the effect of birth
weight on rate of gain under a laboratory environment and to compare
the relative feed consumption and efficiency of feed utilization under
this same environment.
For conventionally reared pigs, a significant difference
(P < .05) was found between the birth weight groups for the number
of days required to grow from 4 to 15 pounds; pigs of heavier birth
weights required significantly fewer days. A significant difference (P < .05) was found between birth
weight groups for average daily gain from birth to 25 pounds with the
pigs of light birth weights gaining more slowly than pigs of heavier
birth weights.
Highly significant (P < .01) correlation coefficients were
found for birth weight with total gain to 56 days and birth weight with
the number of days required to grow from 4 to 15 pounds. Birth
weight was significantly (P < .05) correlated with average daily gain
from birth to 25 pounds. No association (P > .05) was found for
birth weight with the number of days required to grow from 10 to
25 pounds or for the number of days required to grow from 4 to 25
pounds,
No significant difference (P > .05) was found between birth
weight groups for the number of days required to grow from 10 to 25
pounds or from 4 to 25 pounds. The conclusion was drawn that pigs
of light birth weight are adversely affected by neonatal environmental
conditions in the expression of their ability to grow but become equally
as competent as their initially heavier litter mates in this respect
during later preweaning life.
Under laboratory conditions, no significant differences
(P > .05) occurred between pigs of light and moderate birth weights,
for rate of gain, total feed consumption or efficiency of feed utilization.
From these data it was concluded that: (1) pigs of light birth weight have the innate capacity to grow as rapidly, and with as much
efficiency, as pigs of heavier birth weight; (2) the use of a weight
constant preweaning test period seems to more accurately indicate
actual genotypic differences of pigs than does an age constant test
period; (3) when given environmental conditions which adequately
provide for their needs, pigs of light birth weight are as economically
productive as their littermates which were heavier at birth; and (4)
pigs of light birth weight are not genetically inferior and, for this
reason, their use in a selection program can increase the number of
animals from which selections can be made, with consequent
increased opportunity for efficiency of selection.
Genre Thesis/Dissertation
Topic Swine
Identifier http://hdl.handle.net/1957/48593

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