Influence of restricted food intake on estrous cycles and pseudopregnancies in dogs.
OBJECTIVE
To examine effects of restricted food intake on estrous cycle frequency, interestrus interval, and pseudopregnancy prevalence in dogs.


METHODS
28 female Labrador Retrievers.


METHODS
Dogs were paired by body weight when they were 6 weeks old and fed so that the limit-fed pair-mate received 75% of the amount of food offered to its maintenance-fed counterpart. Estrous cycle, interestrus interval, and pseudopregnancy data were recorded.


RESULTS
Mean annual frequency of estrous cycles and duration of interestrus intervals did not differ between feeding groups. Prevalence of clinically evident pseudopregnancy was significantly greater among females that were maintenance fed, although results of endocrinologic testing did not identify a mechanism for this observation.


CONCLUSIONS
Pseudopregnancy in dogs can be influenced by physiologic factors related to nutrition. Clinicians should consider a variety of physiologic and environmental factors when evaluating reproductive function in dogs.
Department of Pet Products Research and Development, Ralston Purina Co, Checkerboard Square, St Louis, MO 63164, USA.
D F
DF
Lawler
S D
SD
Johnston
D G
DG
Keltner
J M
JM
Ballam
R D
RD
Kealy
T
T
Bunte
G
G
Lust
S L
SL
Mantz
R C
RC
Nie
D000367:Age Factors; D000821:Animal Feed; D000818:Animals; D019540:Area Under Curve; D004285:Dogs / Q000378:metabolism / Q000502:physiology*; D004435:Eating / Q000502:physiology*; D004958:Estradiol / Q000097:blood; D004971:Estrus / Q000378:metabolism / Q000502:physiology*; D005260:Female; D008297:Male; D015995:Prevalence; D011374:Progesterone / Q000097:blood; D011388:Prolactin / Q000097:blood; D011555:Pseudopregnancy / Q000378:metabolism / Q000503:physiopathology / Q000662:veterinary*; D011863:Radioimmunoassay / Q000662:veterinary; D011897:Random Allocation; D012044:Regression Analysis
D011374:Progesterone; D004958:Estradiol; D011388:Prolactin