Serum concentrations of thyroid hormones during egg laying in two types of Japanese quail (Coturnix coturnix japonica).
In the present investigation a lighter white egg-type (L) and a heavier wild meat-type (M) of female Japanese quails were compared with respect to egg production, body growth, abdominal fat pad, serum thyroxine (T4) and triiodothyronine (T3) concentrations, TRH sensitivity and T4 5'-monodeiodinase activity in liver homogenates. During the investigation period L type layed considerably more eggs and M type was heavier in body weight. Abdominal fat pad in L type quails was significantly higher than in M type ones. L type quails had lower serum T4 and T3 concentrations than M type ones and the liver T4 5'-monodeiodinase activity was higher in M type than in L type quails. Following TRH administration serum T4 and T3 concentrations increase was higher in L type quails than in M type ones. Our results suggest that lower T4 and T3 observed in L type quails reflect a possible metabolic adaptation to egg production. Different activities of 5'-monodeiodinase and of response to TRH may be inherent to these two types of quail.
Janan
J
J
Department of Physiology and Biochemistry, University of Veterinary Sciences, Budapest, Hungary.
Rudas
P
P
Bartha
T
T
Ludrovszky
F
F
D000375:Aging / Q000502:physiology; D000704:Analysis of Variance; D000818:Animals; D001835:Body Weight; D003370:Coturnix / Q000033:anatomy & histology / Q000502:physiology*; D004531:Eggs; D005260:Female; D007453:Iodide Peroxidase / Q000378:metabolism*; D008099:Liver / Q000201:enzymology*; D008460:Meat; D010058:Oviposition / Q000502:physiology*; D013045:Species Specificity; D013973:Thyrotropin-Releasing Hormone / Q000494:pharmacology; D013974:Thyroxine / Q000097:blood*; D014284:Triiodothyronine / Q000097:blood*
D014284:Triiodothyronine; D013973:Thyrotropin-Releasing Hormone; D007453:Iodide Peroxidase; D013974:Thyroxine