Dystocia in the Camelidae

Dystocia is the abnormal progress of the process of birth. The incidence of dystocia in camelidae is very low.^{(4, 7, 49)} In llamas this incidence has been estimated at 2 to 5%.^{(39, 42, 46, 55, 56)} In our laboratory, dystocia was observed in 16 dromedaries (4.6%) out of 350 births. In most cases of dystocia, intervention occurs during the second stage of labor after observation of a failure of normal progression of the first stage of labor.

Diagnosis of dystocia

Early diagnosis of dystocia is very important because it can evolve very rapidly to a critical situation, endangering the life of both the fetus and the dam. Most of the cases of dystocia are first suspected by the owner or herdsmen. Therefore, it is mandatory that they be trained to recognize signs of abnormal parturition and know when to call for veterinary help. There is no substitute for frequent monitoring of the preparturient female for the early detection of birth complications. This implies that the due date (breeding date) is known and that the owner or herdsmen is familiar with premonitory signs of parturition and the normal process of birth including duration of each stage. Lack of exact breeding-date history is the most common problem when dealing with the parturient dromedary in the field. Development of reliable methods based on biochemical changes in mammary secretion such as those used in the equine will be very helpful for management of parturition in the camelidae.⁽⁷⁴⁾ Experience in identifying and handling animals with dystocia can only be gained by careful observation of several births. Therefore many owners with only one or two animals will always be lacking the expertise needed to deal with parturition and tend either to overlook problems or to be easily alarmed. In the equine, monitoring of parturition in valuable animals can be done using electronic means such as closed circuit video-monitoring, or devices than can sense stretching of the vulvar lips.⁽⁷⁴⁾ At the present time, we are studying electronic means for surveillance of births in the dromedary camels based on these techniques.

Signs of dystocia

Dystocia can occur any time during the process of parturition, the most important sign being the increased duration of stages of labor. Dystocia should be suspected if the first or second stages of labor exceed, respectively, 6 and 2 hours. In addition to this increased duration of labor, the dam may show signs of distress with frequent alternation between standing and sitting positions, with frequent rolling from side to side and excessive straining. Many dromedary females will show profuse diarrhea and frequent vocalization in case of dystocia.

Examination of the parturient

Examination of the parturient should be a routine practice for all animals showing signs of first-stage labor. A thorough anamnesis should be taken before proceeding to examination. History of the parturient should include age, number and normalcy of previous parturitions, the exact breeding date, and signs suggesting beginning of labor (isolation from the herd, off feed...). It is very important to make sure that the female is not in the process of abortion rather than parturition. Abortion is rarely accompanied by dystocia because the fetus is smaller.

Any female that shows signs of distress or increased duration of labor should be examined to assess the position, posture, and presentation of the fetus. This examination is ideally accomplished on the standing animal. However, in most field situations, particularly in the dromedary and Bactrian, this is not possible and the animal has to be examined while restrained in the sitting position as described earlier (cf. Breeding Soundness examination of the female). Examination of the parturient camelidae should be done with extreme care so as not to cause injuries to the birth canal or the rectum because of the normal reaction of the female's expulsive efforts during manipulation. The tail should be wrapped and held or tied to the side. In the dromedary, we start with a rectal palpation examination which is usually very helpful to diagnose uterine torsion. This rectal palpation also allows emptying of the rectum from fecal material and assessment of uterine contraction. Examination of the parturient is continued by vaginal palpation. After thoroughly cleaning the perineal region with water and mild disinfectant, the well-lubricated and disinfected hand is introduced into the vagina. The birth canal should be examined for the presence of twists (uterine torsion) or lesions from previous examinations or injuries. The size and dilation of the pelvic canal should be evaluated. If the cervix is open and the fetus is accessible, its viability is evaluated by its reactions to pinching the toes, pushing gently on the eye, or pulling on the tongue in anterior presentation and by inserting a finger in the anus if in posterior presentation. Viability of the fetus can also be detected by the umbilical pulse if it can be reached. If the cervix is closed, the viability of the fetus can be judged by its movement after direct palpation or by palpation of the fremitus of the uterine arteries.

Obstetrical examination and manipulation can be very difficult if the birth canal is very small (llamas, alpacas and young dromedaries), or if the operator's hands are too large. Examination results should be able to define the presentation, posture and position of the fetus and its viability, and determine the course of action to be taken.

Types of dystocia in camelidae

Types of dystocia are generally classified into two groups: dystocia of maternal origin and dystocia of fetal origin. Dystocia of maternal origin is due to a displacement of the uterus (torsion), uterine inertia, or to disproportion between fetal size and size of the pelvic canal. Dystocia of fetal origin is due to abnormal fetal position or posture such as carpal flexion, lateral deviation of the head, as well as hip and hock flexion in posterior presentation. Feto--pelvic disproportion, monstrosities and transverse presentations are rare.^{(3, 5-7)}

Dystocia of maternal origin

Uterine torsion

Uterine torsion is probably the most common cause of dystocia of maternal origin. It has been described in llamas^{(28, 36, 56)} and dromedaries.^{(22, 32, 53, 57)} All reported cases were treated with various degrees of success by cesarean section (cf. Pathology of pregnancy).

Immature female

Dystocia due to the small size of the dam is not frequent if the breeding management is adequate and the females are not bred until they reach the appropriate size. Although rare, cases of feto-maternal disproportion have been described both in the dromedary and the llama ^{(31, 56, 63)}. Theses conditions are diagnosed after an unsuccessful, lengthy, second stage of labor. The external genitalia may be swollen and the vulva lacerated due to prolonged expulsive efforts. In the dromedary female, difficulties of fetal expulsion are usually due to failure of the vulva to stretch sufficiently to allow passage of the head of the fetus. Management of this type of dystocia consists of evaluating the birth canal and helping the vulva to stretch, or performing an episiotomy. If these procedures are unfruitful and the fetus is alive, the female should be immediately prepared for cesarean section.

Uterine inertia

Dystocia may be due to weak or absent contractions of the uterus (uterine inertia). This is occasionally seen in old animals or animals with prolonged pregnancy. We have observed a case of uterine inertia in an old dromedary female with chronic arthritis.

Dystocia of fetal origin

Dystocia of fetal origin is generally due to a fetal abnormality or to an abnormal presentation or posture. Dystocia of fetal origin due to oversized fetus is relatively rare in camelidae.⁽⁴⁹⁾

Fetal monster

Fetal monstrosities are very rare in camelidae,⁽⁷⁾ but at least two cases of dystocia due to fetal monstrosity were reported in the dromedary. One was due to Schistosoma reflexus,⁽²²⁾ and the other to muscle contracture, bilateral flexion of the carpus, ankylosis of the hind limbs, and complete stiffness of neck.⁽¹⁶⁾ Both cases were relieved by cesarean section. Other anomalies include fetal anasarca and emphysematous fetus resulting from death and putrification (Figure 10.3).

Abnormal presentation

Abnormal presentation, posture, or position of the fetus are probably the most common causes of the dystocia of fetal origin in camelidae (Table 1). This is due to the long neck and limbs of the fetus in these species.
 

* delivered by cesarean section
** delivered after fetotomy
 

Management of dystocia cases

Treatment of dystocia in camelidae is relatively difficult because of the length of the fetal limbs and neck and the narrowness of the birth canal, especially in young dromedaries and in llamas and alpacas. Techniques used for the treatment of dystocia in camelidae are similar to those used in other large animals and include: correction of
position or posture by repulsion, rotation, forced extraction, fetotomy, and delivery by cesarean section.^{(6, 7)}

Repulsion of the fetus consists of pushing the engaged fetal part back into the uterus in order to create enough space in the birth canal to allow manipulation of the limbs or the head to correct postural problems such as limb flexures and head deviations. Repulsion can be obtained by direct manual pressure on the fetus or by using a repulsion rod. It is easily accomplished if the animal receives tocolytic medication or epidural anesthesia before manipulation. Repulsion of the fetus is mandatory for any correction of head or limb deviation.

Rotation of the fetus is used to align parts of the fetus that are most likely to lock inside the birth canal (hips in posterior presentation and shoulders in anterior presentation), with the largest diameter of the pelvis. Shoulder lock is the most common problem in camelidae especially in the case of feto-matemal disproportion. To relieve this situation, the fetus should first be rotated in such a way that its greatest width at the withers be in the same alignment as the largest diameter of the pelvis. This rotation is usually between 45 and 90° and must be done before engagement of the shoulders in the birth canal. If this has already occurred, it may be necessary to repulse the fetus before proceeding with the rotation and traction. In posterior presentation, locking usually occurs at the hips. In these cases, the fetus should be rotated at 45°, preferably with the dam in a lateral recumbency.

Forced extraction or fetal traction is probably the most used technique to relieve simple dystocia. This approach should be used with care to avoid damage to the birth canal and the fetus. In the llama and alpaca, its is very important to make sure that the birth canal is well dilated. This can be aided manually by using abundant lubrication and inserting the hand with the palm outwards and pressing against the vaginal wall.^{(31, 56)} Traction should be applied to each forelimb separately in an alternating fashion to minimize the width at the shoulders (Figure 10.4).
 

Fetotomy can be practiced in the camelidae female only if the birth canal is sufficiently wide to allow easy manipulation of the fetotome. This is not always possible and most veterinarians practice only partial fetotomies usually involving the head or one limb in order to have sufficient space for direct manipulation of the fetus. Fetotomy should be done ethically and only if the fetus is dead.

Cesarean section is probably the most-used technique in the handling of complicated cases of dystocia in the female camelidae. It is a relatively simple technique with very few complications, especially if done before the onset of depression or toxemia in the dam (cf. Surgery of the female reproductive tract).

Corrections of dystocia with limbs crossed above the bead

This posture is characterized by the forelimbs crossed above the head with only the nose apparent at the vulva. It is the leading cause of perineal lacerations. Correction of this form of dystocia is relatively easy using fetal repulsion followed by correction of the position of the fetal limbs.

Correction of bead and neck deviations

Deviation of the head is probably the most common cause of dystocia in camelidae. This is due to the long and flexible neck in this species. It is sometimes complicated by shoulder or carpal flexion of one or both forelimbs. Deviation of the head can be lateral, dorsal or ventral (Figure 10.5). Correction of head deviation can be difficult because of the long neck. In llamas and alpacas, traction on a snare placed around the head or lower jaw combined with repulsion of the fetal thorax can help bring the head and neck into normal posture. We have successfully used a similar technique in the female dromedary. Also in the dromedary, we have been able to correct head posture by using a hook placed in the orbit if the fetus is already dead.

If attempts to correct head deviation fail, the practitioner should suspect the presence of congenital anomaly such as torticollis. In these cases, fetotomy or delivery by cesarean section are the only possibilities. Although fetotomy has been reported in guanaco,⁽⁴⁶⁾ it is seldom possible in the llama and alpaca because of the small size of the pelvis, making manipulation very difficult. Similar difficulties can be encountered in young dromedaries. However, we have been successful in correcting such dystocia after partial fetotomy of a forelimb. Limb removal by fetotomy is advantageous in some case requiring deep manipulation because it provides enough space to reach the head.

Correction of forelimb flexion

Forelimb flexion can occur at the level of the shoulder or the carpus in anterior presentation (Figure 10.6). Correction of caipal flexion is relatively simple and relies on repulsion of the fetus and progressive traction of the flexed limb. Fetotomy may be indicated if the fetus is dead and there is sufficient space in the pelvic canal for manipulation of the fetotome.

Correction of caudal and breeclt presentation

Breech presentations are relatively rare in camelidae but are very serious when they occur (Figure 10.7). This dystocia can quickly lead to the death of the fetus because of the pressure on the umbilicus. A case of breech presentation was described in a Bactrian female which was successfully treated by fetotomy. In this case, fetotomy was performed in tw'o parts- first at the level of the hock, then at the level of the coxo-femoral joint. Manipulation was done after sedation with acepromazine 100 mg + xylazine 500 mg IM.⁽⁶⁰⁾ There was no placental retention following this procedure.
 

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