Stress has long been associated with reproductive dysfunction in all animals, with cortisol playing a role in the interruption of the estrus cycle as well as pregnancy. Cortisol acts in the pregnant animal to interrupt normal placental function. In cattle, heat stress has been demonstrated to affect early embryonic development and may cause higher rates of pregnancy loss. Similar mechanisms are suspected in alpacas and llamas, which is why many producers choose to breed their female animals in the spring or fall to avoid early fetal development and possible pregnancy loss during the hottest days of summer.
Stress from travel by trailer for as little as 30 minutes resulted in increased cortisol levels in alpacas for several hours. Similarly, abortion may occur in females with very high production of fine fiber; in these cases, the female cannot sustain both fiber production and the developing fetus. Defects in placentation may adversely affect pregnancy. Areas of the uterus that previously sustained trauma, resulting in scar tissue formation, will not develop placental attachments.
Premature placental separation from these areas may occur and result in loss of the pregnancy. It is likely that these cases represent a failure of placental development, although other differential diagnoses include chromosomal problems or errors in fetal differentiation and development.
Placental insufficiency, as well as space limitations in the uterus, is the leading cause of abortion of twin fetuses in late gestation; the pregnancies are lost when the placentas are no longer able to supply the required nutrients and oxygen to the fetuses.
Pregnancy loss may be caused by pathology of the cervix. Females that have experienced obstetric manipulations, dystocia, or abortion are at increased risk for cervical tears or vaginal trauma resulting in scar tissue formation and compromise of normal cervical function.
Even females that experience a seemingly normal parturition may sustain cervical damage, which highlights the importance of postpartum vaginal examination. Many cervical tears will heal with surgical or nonsurgical management, but the competency of the cervix may remain unknown until pregnancy is established, lost, or both. The most common embryonic or fetal factors that may result in pregnancy loss are twinning or severe abnormalities.
As in other large domestic animal species, nearly all twins are conceived from double ovulations. A tendency for increased ovulation rate is seen in animals with good body condition. However, a genetic predisposition for twinning may also exist, as some females have a tendency to double ovulate and conceive twins repeatedly. Hormonal induction of ovulation with gonadotropin-releasing hormone GnRH or human chorionic gonadotropin hCG has been suspected to increased double ovulation, but this has not been confirmed in controlled studies.
If one of the fetuses is not eliminated by 45 days, the majority of twin pregnancies will end with abortion in mid- to late gestation. A, 20 days. B, 28 days old twin pregnancy; one undergoing early embryonic death small no heart beat. C, Bilateral twins at 25 days.
E, Early embryo loss due to unilateral twins at 30 days; note the increased thickness of the uterine wall. In general, a twin pregnancy established in the same uterine horn will undergo total loss. We have seen cases of self-reduced twin pregnancy in which the retained fetus was in the right horn of the dam's uterus. Such cases should be flagged by the veterinarian as high-risk pregnancies, as the right horn is typically smaller, and an increased risk for late abortion may exist.
Despite the tendency for early self-reduction, cases of aborted twin fetuses later in gestation have been reported; this highlights the need for early and accurate diagnosis. Pregnancy diagnosis should not be limited to a checkup if the female is pregnant but should include evaluation of the size of the embryonic vesicle, examination of both uterine horns, and, most importantly, examination of both ovaries for quality and number of corpora lutea.
Anytime a double ovulation two corpora lutea is identified in the pregnancy diagnosis at 14 days, the females should be closely monitored for presence of twins and their location. This can be easily done by detection of two fetal heart beats or concepti proper by day Our recommendation is to eliminate both twins if they are bilateral.
If the twins are unilateral, another evaluation is scheduled between 30 and 45 days of pregnancy. If the pregnancy is not reduced to a singleton by this time, a decision to abort both should be considered. Abortion at this stage of pregnancy does not have any effect on the welfare and future fertility of the dam compared with late-term abortion or even the birth of twins, which may cause dystocia and damage to the cervix.
They are usually of unequal size and smaller than the normal gestation age Figure Although rare, conjoined twins are possible and may cause dystocia during abortion Figure Birth of a normal cria with the mummified remains of a twin is possible. Females with recurrent twinning on consecutive cycles after abortion have been documented Dietrich Volkmann, personal communication.
In these cases, monitoring of follicular dynamics and reduction of nutritional plan may help reduce the chances of double ovulation. Unfortunately, no easy techniques exist for manual reduction of twins. A, days of pregnancy in advanced stage of autolysis. B, days pregnancy; one of the fetuses is still fresh, and the other is in advanced stage of autolysis. Although many cria with severe congenital abnormalities are carried to term, we have seen abortion or stillbirth in cases of severe fetal malformations such as hydrocephalus, conjoined twins, cyclopia, and so on Figure Early pregnancy loss caused by chromosomal abnormalities in the dam or the embryo has been suspected but remains poorly studied.
Aborted fetus with multiple severe congenital abnormalities dicephalia, spina bifida, and diaphragmatic hernia. Umbilical cord torsion has been documented as a cause of mid- to late-term abortion in alpacas and llamas.
Abortion may also be the result of twisting of the umbilical cord around the fetal body itself causing severe developmental abnormality. Other placental abnormalities associated with abortion include poorly developed mineralized placental villi and avillous areas.
Complete avoidance of abortion in alpacas and llamas cannot always be achieved; however, some management practices may reduce the incidence or at least prevent abortion storms. Programs designed to reduce the transmission of infectious agents among individual animals, groups of animals, or facilities are paramount in maintaining animal health.
Segregation of animals based on sex, age, and pregnancy status may help reduce transmission of infectious organisms. Females that have aborted, animals newly introduced, or animals returning to the farm from a show should be quarantined for a period of at least 3 weeks.
The same precaution should be observed at shows. Animals in quarantine should be monitored daily for fever and any signs of lethargy, inappetence, diarrhea, or other signs of disease. Reproductive examinations should be performed on any new breeding stock, especially females with a history of infertility or pregnancy loss, and any males.
Producers should have a plan in effect in the event that abortion occurs, including isolation of the affected female, collection of aborted materials for submission to the veterinarian or diagnostic laboratory, and examination of the female and the abortus.
Adequate nutrition, parasite control, and immunization programs for the herd are the basis for elimination of some of the causes of abortion. Vaccination against leptospirosis should be performed only in areas that have experienced outbreaks. Use of multivalent vaccines may cause pregnancy loss, and we do not recommend vaccination of any female in the first 90 days of gestation.
Although camelids and horses both have epitheliochorial microcotyledonary and diffuse placentation, their cervical anatomies are different. Camelids possess cartilaginous rings, which close tightly under the influence of progesterone. The mare's cervix is composed of longitudinal folds, which can easily be dilated even during pregnancy.
This difference in cervical anatomy is likely the main reason that camelids do not experience the same incidence or severity of ascending placentitis compared with mares. In fact, ascending placentitis in alpacas and llamas is extremely rare, and when it does occur, it is often so acute that it is only observed after abortion.
Ascending bacterial placentitis has been observed A. Tibary, personal observation in females that experience recurrent vaginal prolapse during late pregnancy. Placentitis is a common feature of bacterial and parasitic causes of abortion.
Nonspecific hematogenous placentitis is often suspected in cases of fetal loss in which the dam was diagnosed with severe dental disease, gastric ulcers, or metabolic disorders, although these have not been definitively demonstrated. Fungal placentitis has been diagnosed in a primiparous alpaca that aborted at days of gestation.
A diagnosis of placentitis may be made in the gravid female by ultrasonographic examination of the combined thickness of uterus and placenta CTUP , which may demonstrate thickening or separation of the placenta from the endometrium. Impending abortion should be suspected in these cases Figure Treatment of placentitis in alpacas and llamas is extrapolated from treatment in the equine, but these treatments usually fail in camelids because by the time the diagnosis is made the fetoplacental unit is severely compromised.
These cases are usually diagnosed while monitoring pregnant females with other systemic diseases or following major surgeries. Although the pregnancy usually cannot be saved, knowledge of imminent abortion allows the clinician to adjust the intensive care, as some of these females may not be able to expel the fetus or placenta. A, Placentitis with increased uterine thickness. B, Placental detachment and peritonitis note the fluid accumulation in the peritoneum. C, Severe uterine edema and placental detachment,.
D, Uterine rupture with accumulation of fluid within the peritoneal cavity. BW , body wall; P , peritoneal cavity; Pl , placenta; U , uterine wall.
Primary ketosis, or pregnancy toxemia, is a rare feature of pregnancy in camelids compared with that in small ruminant species. However, pregnancy toxemia is often secondary to other illnesses and to uterine torsion. Primary ketosis was described in a 3-year-old alpaca that developed ketosis in the 11th month of pregnancy. Azotemia and hyperlipidemia are often observed in some females. In severely debilitated females, induction of abortion or parturition should be considered to alleviate the syndrome.
Vaginal prolapse occurs most commonly in the last 2 months of gestation. Suspected risk factors include genetics; advanced age, parity, poor or excess body condition during pregnancy; excessive straining or tenesmus, which may be related to gastrointestinal parasitic infestation; or an excessively large fetus. Estrogens increase substantially in the last few weeks of pregnancy and result in increased relaxation of the vulva and the perineal area.
The degree and severity of the prolapse is variable. Mild cases may be evident only when the female is in the cushed position, with only a small amount of vaginal mucosa visible.
The mucosa in these cases is healthy, pink, and shiny with normal moisture. These cases require no treatment, but the female should be monitored for progression of the prolapse, which may warrant veterinary attention.
Topical oil-based antibiotics such as triple antibiotic ointment or antibiotic-impregnated lanolin without corticosteroids may be applied to the exposed tissue for protection. The tail should be kept clean, and the female should be placed in a dry environment to minimize the risk of ascending infection.
Severe cases of vaginal prolapse are likely to involve not only the vagina but also the cervix and the urinary bladder Figure Once the prolapse has occurred, the female will be unable to resolve it on her own. If the prolapse was identified early, prompt treatment will result in the least amount of tissue damage. Epidural anesthesia is often not required but may be considered in severe cases. The tissue is cleaned with a very dilute mild antiseptic solution such as dilute chlorhexidine and saline.
Ultrasonographic examination of the prolapsed tissue may demonstrate involvement of the urinary bladder or the fetoplacental unit. The prolapsed tissue is replaced. Direct pressure of the fingertips is contraindicated because of the risk of rupture. In cases of longstanding prolapse, the tissue may be necrotic, and extreme care must be taken to minimize the amount of tissue damage during replacement. A tube speculum or a round smooth rigid object may be employed to ensure complete replacement of the vagina to the level of the cervix.
Use of sugar solutions or manual pressure to relive excessive tissue edema is commonly reported but often unnecessary. A, Vaginal prolapse in a days pregnant alpaca with poor body condition. B, The prolapsed tissue is cleaned with saline and replaced. C, Vulvar appearance after replacement of the vaginal prolapse. Retention of the prolapsed tissue is often achieved with external sutures. Options include surgical vulvuloplasty, placement of a Buhner or purse string suture, or placement of a shoe-string suture of umbilical tape with nonabsorbable stay sutures.
The needle with the umbilical tape is then inserted on the other side, starting dorsally at the same level and coming down ventrally to the level of initial lead see Figure , B. If a shoe-string pattern is desired, two to three loops of nonabsorbable suture material are made on each side of the vulva, and the umbilical tape is passed through and secured with a knot see Figure , C. Sutures should be removed prior to parturition to allow passage of the fetus. Methods used in sheep to manage vaginal prolapse, for example, a vaginal retainer or straining harness, are not useful in alpacas or llamas.
A, Postmortem curved or ski needle and umbilical tape used for a Buhner suture in alpacas and llamas. B, Buhner suture in an alpaca. C, Shoe-lace pattern using three suture loops on each side of the vulva. Damaged or necrotic tissue, once replaced, will either slough or undergo a period of remodeling. If only the mucosa was affected, often the convalescence period is shorter, although the risk of vaginal adhesions is high. Insertion of antibiotic and antiinflammatory impregnated lanolin into the vagina will help prevent adhesions and provide local therapy.
Use of topicals that contain corticosteroids are contraindicated in all camelids and will likely lead to abortion. Complications of vaginal prolapse are rare in camelids. Females that develop severe vaginal prolapse should be treated with broad-spectrum antibiotics and monitored for abortion. As in other species, the risk of recurrence in subsequent pregnancies is thought to be high, and breeding the animal again after parturition is not recommended.
The risk of genetic predisposition to prolapse of the vagina is also highly suspected but not proven. Torsion of the gravid uterus is, by far, the most common emergency in pregnant alpacas and llamas, and producers and veterinarians should have a plan in place for any pregnant female in which a uterine torsion is suspected.
The female may present to the veterinarian with various stages of pregnancy, from 8 months to term, when the fetus reaches a weight that can sustain the position of the torsion if it occurs. Uterine torsion is suspected to be the leading cause of dystocia in alpaca and llamas. The rolling behavior of the dam and the size of the fetus are often cited as the main contributing factors. A tendency towards increased incidence during the summer months is suspected to be related to increased dusting behavior.
It is interesting to note that uterine torsion is rarely mentioned in the South American literature as a significant problem compared with North America and Australia. This geographic difference may be explained by the small birth weights and smaller body size of alpacas in South America. Another major difference is the extreme variation in the duration of pregnancy in llamas and alpacas observed outside of South America, which may be a contributing factor.
The most common presenting complaint is mild to moderate changes in the behavior and demeanor of the dam. Acute unrelenting pain is rarely an initial sign unless the torsion is severe. Uterine torsion is unlikely to be a sudden phenomenon but rather a progressive complication of a partially rotated uterus. Fetal movements and rolling of the dam may contribute to the final stages of torsion. Females may have decreased appetite, visit the manure pile frequently, quick at her abdomen, or lie in lateral recumbency.
In advanced cases, depression, diarrhea, and anorexia may be the only clinical signs. Astute producers may notice a slight listlessness and less activity than normal.
If the torsion is slight, often the female will not show signs of debilitation as the uterine vasculature will continue to supply the organ. The female may continue to eat and defecate normally. In severe torsions, the uterine vasculature may become occluded, leading to compromise of the uterus and the fetus.
Additionally, the more severe the rotation, the more tension is placed on the broad ligament, which will cause more severe pain and clinical signs in the animal. The female may show tachycardia, tachypnea, and increased vocalization. Noticeable discomfort is often seen in maiden late-term females. Time to referral is critical in cases of severe torsion, as prolonged torsion may reduce the chances of survival of both the female and the fetus.
Animals that display prolonged anorexia, are depressed or recumbent, or are in a state of shock have a poorer prognosis for survival. The longer the blood supply is diminished to the uterus, the more friable it becomes, and treatment options are limited to surgical methods because of the high risk of uterine rupture during rolling. Less debilitated animals are also better candidates for general anesthesia should a cesarean section be indicated.
Diagnosis of uterine torsion in camelids is by transrectal palpation, with use of extreme caution and copious amounts of lidocaine-infused lubricant, especially in smaller alpacas.
Sedation and or epidural anesthesia may be required for palpation per rectum. Most uterine torsions in camelids are precervical in nature, and a vaginal examination either by palpation or speculum will not demonstrate any spiraling of the vagina.
Therefore, the most definitive means of diagnosis is palpation of the broad ligaments, noting the degree of tension and location of the fetus. The location of the fetus is often more cranial than normal and difficult to palpate. In clockwise torsion, the left broad ligament stretches diagonally from the left side to the right side of the animal as a tight band running over the uterine body, whereas the right broad ligament is shorter and trapped under the body of the uterus Figure Determination of the direction of the torsion may be very difficult in some situations, and exploratory laparotomy should be performed in these cases.
Camelids ovulate equally from both ovaries but only carry their fetus in the left uterine horn. This has been proposed as the main reason for a higher incidence of clockwise uterine torsion in alpacas and llamas. However, we have observed an abnormal fetal position in several cases of term uterine torsion, which suggests that this may be a factor.
A, Normal position of the broad ligaments arrows in lateral top and caudal bottom views. B, Position of broad ligaments in a clockwise uterine torsion arrows indicate the direction of the torsion. Torsions may be classified by severity 90, , , or degrees. Torsions of 90 degrees may be underrepresented in veterinary accessions, as animals may not be brought to the veterinarian for lack of significant changes in behavior or comfort level. However, some degree torsions will cause clinical discomfort based on the degree of stretching of the broad ligament and positioning of the fetus.
In term pregnancy, uterine torsion may be a cause of dystocia and must be differentiated from other causes of dystocia, most notably fetal malposition and failure of cervical dilation. Females with active contractions with no expulsion of fetal fluid and no progression of fetal tissues should be evaluated for uterine torsion through transrectal palpation.
If no torsion is identified, vaginal examination may demonstrate failure of cervical dilation. If expulsion of fetal fluid is noted, a vaginal examination will easily identify if fetal malposition or failure of complete cervical dilation is the source of dystocia. Transabdominal ultrasonography is an important tool in the initial evaluation of a female with uterine torsion.
Fetal viability may be ascertained by identifying the fetal heart, and fetal heart rate may give indications as to the health of the fetus. Ultrasonographic examination of the uterus and the placenta will also yield important information about the health of the uterus and the pregnancy.
A severe or chronic uterine torsion will lead to increased uterine wall thickness and, if the female is in active labor, potentially placental separation Figure Measurements of the uterine wall may dictate whether rolling of the dam poses a substantial risk for uterine rupture, as thickened walls may be edematous or friable.
In most cases of mild to moderate uterine torsion with normal fetal heart rates and normal uterine wall appearance and thickness on ultrasonographic examination, rolling the female is a viable first option for treatment.
Most new portable ultrasound machines are equipped with color Doppler imaging. This feature is extremely important for the evaluation of uterine perfusion but most importantly of fetal viability, as it is often very difficult to ascertain fetal death. If the heart is not accessible, the clinician may use Doppler ultrasound on fetal aorta or richly vascularized organs such as the liver or the kidney. Blood flow within the umbilical cord may also be verified. A through D, Ultrasonograms of a severe uterine torsion showing broad ligament BL edema and hemorrhage and very thick congested uterine wall U.
Treatment for uterine torsion includes nonsurgical and surgical options. Nonsurgical treatment comprises rolling the female while holding the fetus and uterus stationary in the abdomen. Debilitated females may not be good candidates for rolling because of the risk of uterine rupture. If the female is slightly dulled but not overly debilitated and the uterus has a normal appearance on ultrasonographic examination, it may be possible to roll the female without chemical restraint.
However, if she is bright, a risk to handlers of being kicked exists. If the female's abdomen is not relaxed enough to palpate the fetus, often intramuscular butorphanol is administered to facilitate the procedure. It is crucial to accurately diagnose the direction of torsion, as this will dictate the direction of rolling.
Females are rolled in the same direction as that of the torsion. For clockwise torsions, the female is placed on the ground in right lateral recumbency. In field-settings, a grass pasture or lawn is ideal; in hospital settings, a padded floor or mat may be used. Three to four people are required for a safe, successful rolling attempt. One person controls the head and neck to prevent injury to the female. Often placing a towel over the female's eyes calms the animal.
Another person controls the front limbs and shoulder, and the third person controls the hindlimbs and hips. The person guiding the rolling process uses hand pressure to stabilize the fetus and the uterus of the female. As the female is rolled from right lateral to dorsal to left lateral to sternal recumbency, the person manipulating the fetus will attempt to hold the fetus stationary as the female rolls around it.
This may be accomplished by the handler using just the hands or sometimes the hand on top and the knee on the side. The handler may feel the fetus slip as the torsion resolves or partially resolves. Once rolled to sternal recumbency, the female is repositioned as before and rolled again in the same manner.
This process is repeated three to four times, and the female is then placed in sternal position and examined via transrectal palpation. Successful correction is recognized by easy identification of both broad ligaments and easy access to the uterus and the fetus. It is not possible to overroll the animal and cause a uterine torsion in the opposite direction. In large llamas, the procedure is similar, but heavy sedation of the animal is required. The use of a plank to hold the fetus in place is more practical for rolling llamas.
Correction should not take more than four or five rolling attempts. The most critical aspect of correction of uterine torsion by rolling is to roll the female slowly, making sure that the fetus is always held firmly in place.
The surgical approach should be considered if the rolling is not successful or if the female is increasingly uncomfortable.
Surgical treatment options are based on the stage of pregnancy at which the uterine torsion occurs and the size of the animal. If the fetus is at term or severely compromised or if the female is debilitated, a cesarean section may be warranted.
Surgical correction should also be attempted when the diagnosis is made by exploratory laparotomy. The uterus may be gently rolled within the abdomen via a midline incision. Flooding the abdominal cavity with lactated Ringer solution helps with the correction. In the llama, surgical approaches to the gravid uterus include a ventral midline celiotomy and a left flank laparotomy. In the alpaca, ventral midline celiotomy is the preferred approach, although in debilitated animals, respiratory failure is a significant risk because of the small lung field in these species and the biomechanics involved when the animal is placed in dorsal recumbency.
Care must be taken when detorsing the uterus, as it may be edematous and friable, even if not noted on ultrasonographic examination. These unfortunate stillborns are nevertheless considered incredibly lucky. They can be burnt as an offering to Pachamama, buried under the foundations of the house, or left by a front door, in the belief that they bring prosperity and health, and keep evil spirits away. See All. Reported protozoal causes of abortion in camelids include toxoplasmosis Toxoplasmosis read more Toxoplasma gondii , neosporosis Neosporosis in Animals Neosporosis is a disease caused by infection with protozoal parasites in the genus Neospora, most often N caninum but also N hughesi in horses.
The most commonly observed problems include bovine Trichomoniasis Trichomoniasis read more Tritrichomonas foetus has been isolated from camels, but there is no strong evidence it is involved in abortion. Viral causes of abortion are dominated by bovine viral diarrhea virus Intestinal Diseases in Cattle Determination of the cause of intestinal disease in cattle is based on clinical, epidemiologic, and laboratory findings.
Nonspecific therapy includes oral and parenteral fluid therapy to restore However, abortions due to equine herpesvirus 1 Equine Herpesvirus Infection Equine herpesvirus 1 EHV-1 and equine herpesvirus 4 EHV-4 comprise two antigenically distinct groups of viruses previously referred to as subtypes 1 and 2 of EHV Both viruses are ubiquitous Abortion may occur at any stage of gestation, or a weak, persistently infected cria may be born prematurely.
The birth of a persistently infected animal can have significant effects on a herd of animals. Diagnosis of BVDV infection is based on virus isolation from fetal blood, fetal tissues lymph nodes , and placenta. Immunohistochemistry may be performed on formalin-fixed tissues. PCR on whole blood samples is commonly used to screen newborn crias. From developing new therapies that treat and prevent disease to helping people in need, we are committed to improving health and well-being around the world.
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