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(B.V. Sc., M. V. Sc. Ph. D) Email :gabermegahed@ yahoo. COM 6 December 2005 What is the goal of pregnancy ? unfortunately Failure in reproduction will be occurred : Pregnancy wastage is responsible for most gestation failures in farm animals . Pregnancy wastage can be divided into: death death * Failure of fertilization and Early embryonic loss. * Late embryonic and early fetal death . * Fetal death. * Abortion. Failure of fertilization This mean, the cow returns to estrus regularly at normal interval each insemination. Causes: Infertile bull (natural mating) Handling of Semen Storage of Semen A.I Time of insemination. Site of insemination. Delayed Ovulation. Abnormal uterine environment. Early embryonic death When the embryo dies before day 14 of the estrous cycle then the life span C.L is not prolonged and the cow returns to at a normal interval. Cause : Genetic defects → defect in the embryo itself there is clearly a lack of cytogenetic evidence Deficient maternal environment → which mediated by inadequate luteal function within the first few days of conception. Sudden changes in diet during the critical early embryonic phase which influence upon the uterine environment (protein trace elements). Infection and endocrine imbalance create an adverse environment with in the uterus that prevents the normal development of the embryo. Luteal deficiency may result in embryonic death Stress ( especially heat stress) which create imbalance between oxidant and antioxidants. How can you prevent these early losses? Two possible approaches in the prevention of these early losses are: 1- GnRH injection 2-Progesterone supplementation Before day 6-7 These two approaches leads to 10.3 % improvement in pregnancy rate. Late embryonic or early fetal death: About 10% of late embryos die between 14-42 days. A smaller % of early fetal death occurs after this stage. - The lifespan of the CL in all cases is extended (this means prolonged interval between successive heats) - Cause : The same as those for early embryonic death. Genetic abnormality (4.8-26%) Stress Infections causes Ageing of ova- Ageing of cow. Pregnancy diagnosis. N.B:If large numbers of animals in a herd are involved and if natural service is used and cows have a history of a mucopurulent Vulvae discharge → then campylobacter fetus infection should be expected. Fetal death Intrauterine death of the fetus is not followed by abortion but the fetus is retained instead. It occur between day 43 of gestation and term . The consequences are :* Early fetal death → can be followed by resorption of fetal fluids, autolysis of fetal tissue and membranes which are sometimes not detected. 1- Stillbirth. 2- Fetal maceration 3- Mummification 4- Emphysema 5- Abortion. Stillbirth Stillbirth is defined as the birth of a dead calf after 272 days of gestation. Most stillbirth, parturition. occur during the act of Fetal maceration This occurs as a consequence of fetal death, usually in mid- to late gestation, followed by:-Regression of C.L and opening of the cervix - But the fetus is not aborted and remains in the genital tract -Bacteria enter the genital tract. - Its incidence is 0.09% of pregnancies. - Maceration with a closed cervix is rare. - Usually a chronic, fetid reddish- gray watery or mucopurulent discharge from vulva over a period of several week. - may be toxic merits early but systemic illness sometime occur . - Gradual might loss. - No satisfactory treatment . - Poor breeding prognosis due to endometrial damage. Fetal mummification After fetal death There is resorption of fetal fluids - Dehydration of fetal tissue and associated membranes - persistence of the C.L. Its incidence is 0.43- 1.8% of pregnancies. This condition occurs in the third to eighth month of gestation but mostly the fourth and sixth months. The causes of F. mummification: Genetic factor → there is a greater incidence in the Jersey, Guernsey breeds Torsion or compression of the umbilical cord by its passing around a fetal extremity. May follow infectious causes of fetal death such as campylobacter fetus, molds BVD- MD virus, leptospirsis but not brucella. Trauma From a clinical point of view, this condition will be identified when a cow - Fail to calve at the expected time. - Fails to show udder development. - On rectal palpation , a hard mass will be identified in the uterus. - No caruncles or cotyledons will be palpable - There is a weak of fremitus in the middle uterine artery. Types of Fetal mummification The hematic type in cattle The papyraceous type in the other species Variable amount of is not characterized by hemorrhage occurs Between placental hemorrhage and the the endometrium and fetal fetus is usually a brownish Membranes↓ This occur after the plasma color and the fetal membranes are not covered with this has been absorbed leaves a reddish - brown material. reddish- brown , gummy tenacious mass of cells, clots and mucus Handling of mummified fetus (Treatment ) Termination of pregnancy and delivery of the fetus may be a goal of treatment. Manual removal of the C.L is effective when the ovaries are easy reach (With risk ovarian damage or hemorrhage). Single dos of PGF2α (25mg) or 0.5 -1.0 mg of its analogue given intramuscularly will be expelled the fetal mummy within 3-5 days. Total expulsion does not take place (because of insufficient lubrication) completely Manual removal of the fetus will be occur with lubricant followed by Uterine irrigation with antibiotic, sometime , use irrigation with 1: 2000 acriflavine or normal saline Intramuscular dose of 10-20mg of ergometrine to overcome uterine atony. Systemic antibiotic according to animal healthy condition Breeding prognosis will be good and conceive in 1-3 months. Fetal emphysema - Similar to maceration - Putrefactive bacteria invade through open cervix. - Fetal death may be associated with dystocia. - From the clinical point of view, the gross fetal changes include →Putrefaction distension with crepitation and dry hair. -Fetal emphysema complicating dystocia commonly Fetal to dam. - May be poor prognosis. Abortion Abortion is defined as the expulsion of a dead or non-viable fetus at any stage of pregnancy before the time of normal parturition (late 2nd and 3rd trimester). Its frequency is normal for 1-2% of pregnant cows. if the % rises to 5% or more it should be investigated thoroughly. - Causes, clinical finding, pathogenesis, handling, control and eradication were presentation in the another presentation ?