Effect of biosynthetic chicken growth hormone on egg production in White Leghorn hens.
Two studies were conducted to determine if injection of recombinant chicken growth hormone (cGH) influences egg production parameters in older laying hens. In both experiments, hens were subjected to consecutive 3-wk periods consisting of 1) a preinjection period, 2) an injection period, and 3) a postinjection period. During the 3-wk injection period, hens were injected once daily with either 5, 50 or 500 micrograms/kg BW of cGH or physiological saline (vehicle) alone (control group). In both experiments, injection of cGH did not affect (P greater than .05) percentage of daily egg production per hen, Haugh units, or BW during the injection period compared with preinjection hens. In Experiment 1, but not Experiment 2, control hens had reduced shell thickness and feed consumption during the injection and postinjection periods when compared with the preinjection controls. These reductions were not observed in hens receiving injections of cGH (all doses).
Donoghue
D J
DJ
Department of Animal Science, Rutgers, State University of New Jersey, New Brunswick 08903-0231.
Campbell
R M
RM
Scanes
C G
CG
D000375:Aging / Q000502:physiology; D000818:Animals; D001835:Body Weight / Q000187:drug effects; D002645:Chickens / Q000502:physiology*; D004435:Eating / Q000187:drug effects; D005260:Female; D013006:Growth Hormone / Q000494:pharmacology*; D010058:Oviposition / Q000187:drug effects*; D011994:Recombinant Proteins / Q000494:pharmacology
D011994:Recombinant Proteins; D013006:Growth Hormone