Acute-phase protein profile during gestation and diestrous: proposal for an early pregnancy test in bitches

Early pregnancy diagnosis in bitches has special relevance for adequate medical assistance to assure normal gestation, diagnosis of abortion or embryonic resorption, undesirable pregnancy interruption and dog owners wishing to assure medical assistance during parturition and to program participation of females in dog shows. The aim of this study was to verify acute-phase protein profile variation as a consequence of generalized inflammatory reaction due to embryonic endometrial invasion and use alterations as a method for early pregnancy diagnosis. Also the relationship between hormonal status and acute-phase proteins concentrations was assessed. Weekly serum samples were collected from 20 non-pregnant (NP) bitches and 20 pregnant females (P) to determine levels of fibrinogen, haptoglobin, ceruloplasmin, seromucoid, glycoprotein, alpha(2) globulin, progesterone and estradiol-17beta. No correlation was found between the implantation sites formed (number of pups born) and the hepatic stimulus for the acute-phase protein production. The conclusions are that acute-phase proteins can be used as an early pregnancy test for bitches from the 3rd week of gestation (14th-21st day post LH peak) for haptoglobin assay (values above 112.42 mg/dl of HbCN binding capacity), from the 4th to the 6th week (21st-42nd day post LH peak) for ceruloplasmin (values above 12.76+/-5.29 U/l), from the 4th week (21st-28th day post LH peak) for glycoprotein (values above 13.67%) and from the 4th week of gestation (21st-28th day post LH peak) for alpha(2) globulin (values above 0.61 g/dl). Fibrinogen and seromucoid increased in the P group from the 5th to the 6th week, respectively, thus not being suitable as parameters for an early pregnancy diagnosis. Relationship between ceruloplasmin and estradiol-17beta and seromucoid and progesterone were verified. For the acute-phase protein test it is important to verify bitches' healthy condition and to assure the precise mating dates to avoid false-positive and -negative results, respectively.