Measurement and Significance of Protein Turnover 43Table 2.3.Tabulation of results from protein turnover studies in farm animals.
Model Species Response Reference
3MH kinetic model Swine Myofibrillar proteolysis was increased by van den Hemel-Grooten
27% in protein-deficient barrows; no et al.(1995)
direct relationship between myofibrillar
proteolysis and in vitroproteinase activity
3MH kinetic model Swine Myofibrillar proteolysis was not different van den Hemel-Grooten
from controls swine during the protein et al.(1998)
refeeding period
3MH kinetic model Cattle There was a 20% decrease in 3MH Rathmacher et al. (1993b)
production in the trenebolone acetate-
implanted cattle, but when combined with
an oestrogen implant the decrease was
prevented
3MH kinetic model Dogs In terms of post-surgical nutrition, meeting Rathmacher et al. (1993a)
the protein requirement is critical in
minimizing muscle protein catabolism, and
hyper-supplementation of both energy and
protein has little affect
Urine 3MH Cattle FBR was increased in feed-restricted cattle Jones et al.(1990)
Urine 3MH Cattle No effect on muscle protein breakdown Hayden et al.(1992)
Arterio-venous Sheep Hepatic protein synthesis was maintained Pell et al.(1986)
at the expense of muscle
Whole-body protein Muscle protein synthesis contributes to
turnover–leucine 50% of whole body protein synthesis
Arterio-venous Sheep Whole-body and hind-limb protein Harris et al.(1992)
Whole-body protein synthesis is increased with food intake.
turnover–leucine Leucine oxidation increased with food
intake
[^15 N]Glycine Cattle Whole-body protein synthesis and Wessels et al.(1997)
degradation increase when the limiting
amino acid is given
[^15 N]Glycine Pigs Increased protein accretion with lysine Salter et al.(1990)
supplementation was due to a greater
increase in protein synthesis
Whole-body protein Cattle Steroid-implanted steers had a greater Lobley et al.(1985)
turnover–leucine increase in synthesis and reduced amino
acid oxidation
Whole-body protein Cattle Bovine somatotropin increased the FSR in Eisemann et al. (1989)
turnover–leucine/ muscle and the small intestine
constant infusion
Flooding dose Sheep The FSR was, in decreasing order, intestine, Attaix et al.(1988)
liver and muscle
Flooding dose Sheep Changes in nutrients at weaning enhance Attaix et al.(1992)
protein synthesis without any specific
effect on small intestine site
Constant infusion Swine FSR was higher in ractopamine-fed pigs as Bergen et al.(1989)
compared with controls
Constant infusion Swine Testosterone levels had no effect on muscle Skjaerlund et al. (1994)
growth or turnover
Constant infusion/ Sheep Protein synthesis increases with intake in
flooding dose muscle, skin and liver Lobley et al.(1992)