断奶仔猪(1).pdf

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Weaner Pig Chap 01 26/9/01 2:01 PM Page 1
with an apparent advantage in terms of numbers of pigs born per sow per
year.
The description of growth following weaning requires at its core a prediction of
protein mass and of its incrementation. Description of body composition further
requires quantification of lipid mass and an understanding of any relationship that
may exist between protein and lipid retention in the course of positive (and, in the
case of the weaned pig, negative) growth.
© CAB International 2001. The Weaner Pig: Nutrition and Management
(eds . Varley and J. Wiseman) 1Weaner Pig Chap 01 26/9/01 2:01 PM Page 2
2 . Whittemore and . Green
Theoretical considerations
There is dissent over the nature of the curve that might best describe protein growth
over time and weight. The conventional assumption of a sigmoidal form requires the
rejection of the proposition still held by the de Lange school at Guelph (. de
Lange, personal communication, Guelph, 2000), which follows from the reviews of
Kielanowski (1969) and Rerat (1972) and suggests that a single value be used to
describe maximum daily potential protein retention rate (Prmax) at all times during the
active growing life of the pig. That the (single value) potential for growth is not
achieved in early life, and particularly after weaning, may be ascribed to a failure on the
part of the pig to be able to ingest sufficient feed. In addition to Prmax, the original
models of Whittemore and Fawcett (1974, 1976), and those that later sprang from
them, required a second parameter: t