Lecture Notes on Veterinary Obstetrics, VCT 601 (PPT)BYS.Tona Olurode,DVM,MVSc.(Theriogenology)COLVET, UNAAB

BOVINE PREGNANCY AND ITS DIAGNOSISIndication for Bovine Px Dx:

to detect those non-pregnant so that appropriate measure(s) can be taken.NB:Age at 1st calving is approx 24mos for dairy cows and subsequently at 13-13.5mos intervalsAfter ~60days post insem foetal death rates are low

Pregnancy diagnosisMethods used grouped under the following subheadings:

ManagementChemical or laboratory methodClinical examinationUltrasonography

Managemental methods of px dxNon-return to oestrus and CL persistenceHistory of exposure of cow to a bull or A.I.Mammary gld devpt (useful only in primigravida)Abdominal ballottment possible at ~7mos of gestation in small breeds such as jersey

Chemical or Laboratory methodsEPF/ECF demonstration in serum or milk via commercial test kits using the dip stick principle; early in 3days or later in 7-8 daysProgesterone assay in plasma & milk using RIA or ELISA. Blood sample collected 21days post previous oestrus.Assay of px-specific protein B via RIA good tool for twins identificationOestrone SO4 in milk

Clinical methodsTransrectal palpation, can be done as early as 30days in heifers and 35days in cows.

(disadvantages much practice is reqd) -uterine assymmetry -membrane/foetal slip (see table 1 for the rule of thumb)

Table 1: Calf foetal size at various stages of pregnancy in relation to the size of some commonly known adult animals.

Stage of pregnancy Calf foetal size in relation to the size of commonly known adult animals 2 months Mouse 3 months Rat 4 months Small cat 5 months Large cat 6 months Beagle dog

Table 2: Uterine position/diameter and structures during pregnancy

Stages of Pregnancy (days of gestation) Uterine position Uterine diameter Palpable structures 35-40 Pelvic floor Slightly enlarged Uterine asymmetry/foetal slip 45-50 Pelvic floor 5.0-6.5cm Uterine asymmetry/foetal slip 60 Pelvis/abdomen 6.5-7.0cm Membrane slip 90 Abdomen 8.0-10.0cm Small placentomes/foetus (10-15cm long) 120 Abdomen 12cm Placentomes/foetus (25-30cm long)/fremitus 150 Abdomen 18cm Placentomes/foetus (35-40cm long)/fremitus

Clinical methods contdVaginal examination using either of the following ways:visually with the aid of vaginoscope

manually through pressing the finger directly on the external os of the cervix to detect the presence of an adhesive tenacious secretion

Ultrasonography Requires ultrasonic foetal pulse detector that employs the Doppler principle. 2 types are available; ultrasonic depth analysers (A-mode) with disadv of questionable degree of accuracy as early as 40daysRealtime B-mode method of choice for early px dx in the cow via transrectal imagingFor early pxs 7.5MHz linear transducer is reqd while late pxs prefers 3.5MHz transducersUseful in foetal age estimation (assmt of trunk diameter) up to 140days,CRL not easy to assess; sex determination via migration of genital tubercle-

in male, migration is towards the umbilicus whereas in the female, it is towards the tail

Normal Birth in the cow (Eutocia)Normal birth process= calvingGL averages 290 days, sequel to series of events emanating from the initiation of parturition

Preparatory changes are those associated with the udder, vulva and pelvic ligaments, body T drops 24-48hrs b4 calving, exudation of clear vaginal mucus,tail head might appear raised with gluteal muscles sunken

LABOUR

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Stage 1 of labour

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Stage 2 of labour

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Stage 3 of labour

Events of the 3 stages of labour1st stage cervical dilatation or dilation, the duration is about 3-8 hours in cows but longer in heifers, 24hrs. The cardinal sign is restlessness 2nd stage foetal delivery, the duration averages 2-4 hours in pluriparous cows but longer in heifers, involves straining by the dam3rd stage - placental expulsion, time reqd averages 8 hrs but can last 12hrs sometimes which is still considered normal.

DYSTOCIA

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Causes of DystociaFor convenience, causes are divided into 2:Maternal- primary uterine inertia- ocassioned by multiple or abnormal foetuses which overstretch the uterus, a defect in the myometrium that renders contraction impossible, hormonal defect and periparturient hypocalcaemia. Dam may exhibit few weak abdominal contractions that fail to progress to 2nd stage. On exam.,cervix is found dilated with no foetus in the birth canal. Treatment via gentle traction and correction of position and postural defects. secondary uterine inertia consequent upon myometrial exhaustion. Possible sequelae include retained placenta, delayed uterine involution and uterine prolapse. Treatment is by removal of the impediment. abnormalities of the birth canal-inadequate pelvis, pelvic exostoses, incomplete cervical dilatation, vaginal cystocoele, neoplasms of the vulva and vagina, remnants of mullerian ducts persisting, uterine torsion, stenosis of the vulva and vagina (heritable in some breeds or due to immaturity.

2. Foetal Abnormal foetal presentation, position and postureFoetal monstrosities- Schistosoma reflexus, perosomus elumbus e.t.c.Foetal oversize most common cause in cattle due to foetopelvic disproportion

Obstetrical ProceduresDivided into 4 main groups viz.Mutation- includes repulsion, rotation, eversion, extension or adjustment of the extremities. Useful to return a foetus to normal P. P& P. Forced tractionEmbryotomy Caesarian section

Lambing & KiddingGL ~ 140-150 days on the av.140 days for sheepPrior to EDD, ewe shd be put on observation every 4-6 hours to check for certain conditions like pregnancy toxaemia, hypocalcaemia, vaginal prolapse, abortion, mastitis & rupture of the prepubic tendon. Stages of parturition consult the note!

Causes & Mgt. of dystocia in sheep and goat Goat parturition normally uneventful. If labour extends beyond 30 mins, consider dystocia.Most common forms arise when more than one kids attempt to exit the birth canal at the same time. Other causes are deviation from normal PPP, foetomaternal disproportion, failure of cervical dilatation (ring womb), vaginal prolapse, uterine torsion and uterine inertia.

Causes & Mgt. of dystocia in sheep and goat contdMgt dx based on failure of active labour to be initiated and history.NB: if no delivery accomplished within 2-3 hrs, the cervix will start to close.Protocols of mgt requires:

Strict adherence to general principles of cleanliness, lubrication and gentlenessUse of appropriate restraint techniques epidural anaesthesiaRelief of dystocia

Infectious causes of abortionGoats tend to have high incidence of abortion when compared to other livestock species.Infectious causes of abortion is highly significant. However, all or none principle is assumed during an abortion outbreak i.e. all causes of abortion are infectious in nature

Infectious causes of abortion, therefore, include the following:

ChlamydiosisToxoplasmosisQ-feverListeriosisLeptospirosisMycoplasmosisCampylobacteriosisBrucellosisSalmonellosisYersiniosisTrypanosomosisSarcocystosisanaplasmosis

Non-Infectious causes of abortionEarly embryonic death- due to several physiologic or environmental factors sequel to predisposing factors e.g. stress, nutrition etc. Genetic disorders- habitual abortion may be heritable or cross resulting in abnormal chromosomesNutritional factors- deficient E & protein in the diet most esp in the late gestationToxic plants and pharmaceuticals

POST-PARTUM DISEASESUterine prolapseVaginal prolapseAcute septic metritis (puerperal metritis)MastitisRetained placenta

Foetotomy (Embryotomy)Term used to describe method of dividing the foetus into smaller pieces to ensure easy passage thro the birth canal.Commonly employed in cattle, occasional in horses, rarely in sheep & goat and almost never in pigs and small animals. The technique is a method of choice esp when foetus is ascertained to be dead in utero.

Classification of Foetotomy2 classes basically, viz;

Complete/ TotalIncomplete / Partial2 techniques available

Percutaneous foetotomySubcutaneous foetotomy

Percutaneous foetotomyRequires a tubular embryotome which confers protection on the maternal tissues against damage while sawing through the dead foetusPreferred method for non-decomposed foetuses

Subcutaneous foetotomy

Involves dissecting out foetal parts from within its skin to cause reduction in foetal bulk and allowing the delivery of the remainder mass par vaginum.

Indications for complete foetotomyRelief of dystocia caused by foetal maldispositionRelief of dystocia caused by foetopelvic disproportion (foetal oversize, foetal monsters)Relief of dystocia caused by engaged foetus within the birth canal e.g. stifle lock (hip lock)During CS when large or deformed or maldisposed foetus is encountered

Indications for partial foetotomyDeviation of the headShoulder flexionBreech presentation (bilateral hip flexion)Posterior presentation (hock flexion)Foetal monsters

Care of the dam following foetotomy include :

Manual exam of vagina and uterusAdministration of local and parenteral antibioticsNon-steroidal anti-inflammatory therapyCareful removal of the placenta from the carunclesCareful nursing

Thanks for your attention