Canine pregnancy diagnosis

why we go for pregnancy diagnosis in dogs ? Valuable to clients

Allows appropriate changes in schedule of working of show dogs

Valuable to veterinarians if owner wants early termination of pregnancy in case of mismating.

Allows better management of bitch during pregnancy Rules out pseudo pregnancy at early stage

Methods of PD in bitches Reliable methods of PD Abdominal palpation Radiography Ultra sonography Relaxin assay Acute phase proteins Non reliable methods of PD Evaluation of the teats Weight gain & abdominal enlargement Hormone assays (P4,E2,PRL,FSH,C-Peptides ) Metabolic changes (creatnine and IgG)

Abdominal palpation(AP)

Tradional method of PD in bitches

AP is accurate between 24- to 35-day post- breeding At about 30-35 days the accuracy is high 87%

AP in the flank and also in the lower abdomen

Gestational sacs are palpated as tense conceptual swellings (6 to 30 mm in diameter) within the uterine cornua These swellings double in size every week until days 35 to 38.

A photo showing the

distinct gestational sacs.

A photo showing how the gestational sacs

become confluent, and therefore

difficult to distinguish.

Disadvantages of AP

Difficult without experience to determine the exact number of fetuses.

Fetal viability cannot be verified with palpation.

Position of fetuses is difficult to determine.

Difficult to palpate, especially in obese or tense dogs

Bitches often tense their abdominal wall and respire too fast making abdominal palpation often too difficult to perform Fetal NO. cannot be verified.

Non-traditional method Utrasonography Safe and accurate modality for pregnancy diagnosis 3 types of diagnostic ultrasound for canine pregnancy diagnosis. A-mode, Doppler and B-mode

B-mode, or real time ultrasound is mostly used for PD It allows assessment of; pregnancy status Fetal number and viability Trans abdominal USG in done in dogs Frequency of transducer is set between 3.5 – 5 MHz (most of the dogs) Toy breeds , 7.5 MHz transducer is used

For early PD , 7.5 – 10 MHz transducer is used.

ULTRASONOGRAPHY

24 – 25 Days 94 – 95 % accurate

28 Days 99% accurate Best time 25 – 30 days after

mating Amniotic vesicle - 18 – 21

days fetal heart beat 24 days fetal bones 42 – 45 days

Advantages Safe and accurate method for pregnancy diagnosis.

Method of early pregnancy diagnosis in bitches.

Method of choice for assessment of liveability of foetuses Dis advantages High cost of machine

Not the method of choice for assessment of litter size

Fetal position is difficult to determine

Trained person is required to perform USG

Radiography

Radiography is done after 45 days of mating

100% accurate in last 15 days of pregnancy

Mineralization of bones starts 44 day onwards

Lateral sides are mineralized earlier than ventro dorsal projections

Radiography in lateral recumbency is preferred than dorsal or dorso ventral

voltage should be 50 Kvp current should be 0.5 – 1 mA

Signs of fetal death

Spalding sign, (which is the overlapping of the cranial bones)

Collapse of Skelton Gas shadows in the fetal heart, stomach, around the fetus Tightly flexed spine (seen in fetuses died for long time) Jackson, 2004

Advantages Good in evaluating fetal numbers in the bitches.

Fetus can be differentiated easily from abdominal contents due to mineralization of bones after 45 days.

Position of the fetuses can be easily determined. Number of fetuses can be easily counted. Whelping date can be predicted

Disadvantages Poor in evaluating fetal viability. High cost of machine Hazards of exposure to X Rays to growing fetuses & operator

Hormonal assay

Relaxin Pregnancy-specific hormone in dogs

Secreted by placenta only

Differential hormone between pregnancy & pseudo pregnancy

Peak conc. Between 20–30 days of gestation

Relaxin assay cannot be used to estimate litter size

RELXIN ASSAY KIT

Progesterone Assay Not used for routine diagnosis

conc. remains elevated during diestrus in both pregnant and non pregnant bitch

Prolactin Drastic increase in conc. During 30 – 45 days of gestation FSH Declines blow 150ng/ml after 17 days of pregnancy

ESTROGEN In urine increases 21 days post mating

Acute phase proteins

Increase after day 20 of gestation Released during pregnancy & inflammatory diseases

Include haptoglobin, ceruloplasmin, alpha-globulin, C-reactive protein and fibrinogen.

Serum fibrinogen as a pregnancy confirmatory test is;

98% accurate, with a value >280 mg/dL

Nearly 100% accurate with a value of>300 mg/ dL

Metabolic changesDecreased serum creatinine and IgG in pregnant dogs 21-day post-breeding

Serum creatinine decreased 25–33%, and serum IgG decreased 40–45%

Decrease in antithrombin III activity

Normocytic normochromic anaemia that begins on Days 25–30 of gestation & max at term

General changes in pregnant bitch

Bodyweight gain is 36% (range 20-55%)

Change in body shape after day 56

presence foetal movements day 55 onwards

Nipples enlarge ment after 40 – 45 days