PMID- 18419560
OWN - NLM
STAT- MEDLINE
DCOM- 20081027
LR  - 20080418
IS  - 1537-5293 (Electronic)
IS  - 1522-2152 (Linking)
VI  - 81
IP  - 3
DP  - 2008 May-Jun
TI  - Ovarian activity is differentially regulated across the breeding season in 
      immature compared with adult American crows (Corvus brachyrhynchos).
PG  - 356-65
LID - 10.1086/587095 [doi]
AB  - American crow (Corvus brachyrhynchos) reproduction is seasonal. While photoperiod 
      alters reproductive physiology and behavior in nesting adults, whether seasonal 
      photoperiod changes alter ovarian activity in nonnesting adult and immature birds 
      was not known. Ovarian follicular composition was examined in immature and 
      nonnesting adult crows. Birds were divided into groups reflecting daylight hour 
      exposure when captured: 12L, 12:30L, 13:30L, and 14L, representing early-, 
      progressing-, peak-, and postbreeding seasons in southern California. Adult 
      ovarian mass peaked in 13:30L and then decreased 65% by 14L. In contrast, 
      immature ovarian mass peaked in 12L and decreased 58% by 14L. Whereas no change 
      in adult follicle composition occurred, primordial follicle numbers increased 
      42%, and previtellogenic follicles increased 86% in immatures, resulting in an 
      overall follicle number increase in immatures by 13:30L and 14L. Adult atretic 
      follicles declined 68% by 14L, while immature atretic follicle numbers remained 
      constant. Adult apoptotic transferase-mediated dUTP nick end labeling 
      (TUNEL)-positive follicle numbers remained constant until a 52% decrease occurred 
      in 13:30L. TUNEL-positive follicles declined 58% by 12:30L among immatures. These 
      data are the first to demonstrate that follicular composition is differentially 
      regulated between nonnesting adult and immature American crows. Seasonal ovarian 
      activity alterations in nonbreeding adults may serve to prime individuals for 
      potential mating.
FAU - Dougherty, Coventry O
AU  - Dougherty CO
AD  - Department of Biological Sciences, California State University, Long Beach, 
      California 90840, USA.
FAU - Ross, Wallace L
AU  - Ross WL
FAU - Young, Kelly A
AU  - Young KA
LA  - eng
GR  - Howard Hughes Medical Institute/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - United States
TA  - Physiol Biochem Zool
JT  - Physiological and biochemical zoology : PBZ
JID - 100883369
SB  - IM
MH  - Animals
MH  - *Breeding
MH  - Crows/*physiology
MH  - Female
MH  - Ovary/anatomy & histology/*physiology
MH  - *Seasons
MH  - Sexual Maturation/*physiology
MH  - Time Factors
EDAT- 2008/04/19 09:00
MHDA- 2008/10/28 09:00
CRDT- 2008/04/19 09:00
PHST- 2008/04/19 09:00 [pubmed]
PHST- 2008/10/28 09:00 [medline]
PHST- 2008/04/19 09:00 [entrez]
AID - 10.1086/587095 [doi]
PST - ppublish
SO  - Physiol Biochem Zool. 2008 May-Jun;81(3):356-65. doi: 10.1086/587095.